Pteropus alecto), while also highlighting bat innate immunity as an exciting and fruitful area of research to understand their ability to control viral-mediated pathogenesis.Interferons are an essential component of the innate arm of the immune system and are arguably one of the most important lines of defence against viruses. The human IFN system and its functionality has already been largely characterized and studied in detail. However, the IFN systems of bats have only been marginally examined to date up until the recent developments of the Bat1k project which have now opened new opportunities in research by identifying six new bat genomes to possess novel genes that are likely associated with viral tolerance exhibited in bats. Interestingly, bats have been hypothesized to possess the ability to establish a host-virus relationship where despite being infected, they exhibit limited signs of disease and still retain the ability to transmit the disease into other susceptible hosts. Bats are one of the most abundant and widespread vertebrates on the planet and host many zoonotic viruses that are highly pathogenic to humans. Several genomics, immunological, and biological features are thought to underlie novel antiviral mechanisms of bats. This review aims to explore the bat IFN system and developments in its diverse IFN features, focusing mainly on the model species, the Australian black flying fox ( Interferons (IFNs) are a group of secreted cytokines that can induce an antiviral state of the host and primarily are responsible in inhibiting viral replication. They comprise part of the innate immune response and are one of the first and arguably most important lines of defence produced against viral infection, intended to limit the spread of a virus upon early infection . IFNs weThe IFN induction and signaling processes in response to a viral infection in humans have been discussed extensively elsewhere . BrieflyTLRs are the largest and most widely studied class of PRRs. They are glycoproteins that possess an extracellular domain containing leucine-rich repeats (LRRs) (which recognize a variety of ligands and bind to them), a transmembrane helix and a cytoplasmic signaling Toll/interleukin-1 (IL-1) receptor homology (TIR) domain . TLRs arAlthough TLRs play a very significant role in sensing viral RNA at the cell membrane and in endosomes, it is apparent that additional sensing mechanisms must also take place inside of the cell, within the cytosol to aid in the contribution to host anti-viral defences.RLH receptors are critical components of the anti-viral defence pathway. They are present in almost all cell types and consist of three RNA helicases; retinoic acid-inducible gene (RIG-I), laboratory of genetics and physiology-2 (LGP-2) and melanoma differentiation associated gene (MDA5) . RLHs reTLR9 is primarily expressed in dendritic cells and B cells and is known to stimulate type I IFN production in response to foreign non-methylated CpG DNA in endosomes, via interacting with MyD88 to activate MAPK and NF-κB . There aOnce activated, IFNs are secreted by infected cells where they enter the extracellular space and work to induce an antiviral state in the infected or neighboring cells in an autocrine or paracrine manner, respectively. In addition, they can also moderate innate immune responses to permit the action of antigen presentation and NK cells, but without the detrimental overactivation of pro-inflammatory pathways. Furthermore, IFNs can activate the adaptive immune system to induce specific T and B cell responses to the invading pathogen . There aBats are grouped in the order Chiroptera and are one of the most abundant and geographically widespread vertebrates on Earth. The order Chiroptera can be subdivided into Yinpterochiroptera (consisting of megabats and some microbat species) and Yangochiroptera (composed of the remaining microbat families). Within these suborders high amounts of diversity are observed between bat size, ecological niches, diets, and morphology . There aBats are able to transmit viruses to humans in “spillover events” either directly or via an intermediate host. Significantly, the recent emergence of COVID-19, appears likely to have originated in bats and has entered human populations via an unknown intermediate host, likely traded in the Wuhan market at the epicentre of the outbreak. COVID-19 is the third identified highly pathogenic coronavirus to enter human populations . SequencBats possess unique characteristics that are distinguishable from other mammals which could possibly underlie their ability to harbor many viruses without showing clinical symptoms. However, it should also be understood that most other mammals are also able to harbor many viruses without exhibiting symptoms and it is the bats apparent unique immune characteristics that are important here in allowing them to harbor viruses. Bats are the only mammal capable of powered flight, allowing certain species to travel over large geographical distances during seasonal migrations and in pursuit of food where they may mix with other bat populations and hence contribute to the spread of viruses . Bats alPteropus alecto) and what we can learn from this bat as a model species.These observations and studies highlight the need to explore diversity in the innate antiviral immune responses within this fascinating order of mammals and the seemingly unusual abilities of bats to control virus induced pathologies. In this section, bat IFN systems are discussed with the primary focus being the black flying fox . Studies by As previously discussed, different PRRs have been identified in humans that appear to show certain homology to those found in bats. TLRs have been characterized from the black flying fox and the fruit bat Leschenault’s rousette , the greater flying fox (Pteropus vampyrus), and the little brown bat (Myotis lucifugus) collectively   . IRF7 inrotinus)  found thMyotis davidii, but interestingly not in the black flying fox (The type III IFN receptor (IFNλR) has been well characterized in the black flying fox . It was ying fox  and the Once type I and type III IFNs have bound to their cognate receptors, they activate the same signaling pathway, called the JAK-STAT pathway, which ultimately leads to the activation of antiviral effectors and ISGs, as detailed in The black flying fox can harbor certain viruses without showing signs of disease but can still transmit the virus to other mammals and humans in spillover events, in which the virus can cause pathology in the infected host. It is therefore imperative that this ability as to how these bats remain unharmed while harboring these viruses is unearthed. It is suggested that the evolution of many characteristics of bats such as being the only flying mammal, having long life spans, their nocturnal abilities and reproductive mechanisms, may all contribute to the hypothesized uniqueness of their immune response that has not been observed in any other species. This section will discuss comprehensively the different plausible traits that bats possess, focussing largely on the black flying fox, that may prove advantageous in coexisting with viruses.P. alecto kidney PaKiT03 cells with two bat-borne viruses (Hendra virus and Pulau virus) caused no change in the constitutive IFNα expression pattern. This expression has not been observed in any other species which suggests its significance in the bats ability to coexist with viruses. To ensure that the constitutive IFNα expression was unspecific to the black flying fox, they conducted the same studies using the lesser short nosed fruit bat (Cynopterus brachyotis) and found similar results of continually high IFNα expression across all tissues, regardless of viral stimulation (Research by  was the mulation . Functiomulation . Findingmulation . Additiomulation Table 1.Studies by  have useEptesicus fuscus) indicated a mammalian-like MERS or dsRNA-induced stimulation of IFN production  inflammasome sensor has been proven central to age related and viral-induced inflammation in humans and other mammals.NLRP3 is vital to the inflammasome of cells and its role is to recognize cellular stresses such as mitochondrial damage or oxidative stress, in addition to bacterial or viral infections. NLRP3 is known to respond to a myriad of viruses, including bat-borne viruses such as rabies and influenza . Until rP. alecto and M. davidii) revealed the absence of the PYHIN gene family in both species. Studies by Pteronotus parnellii,) which is thought to be where the bat PYRIN sequence clustered with AIM2, indicating the presence of a functional AIM2 gene in the bat common ancestor that was lost during evolution. All other major groups of placental mammals possess at least one gene member, whereas most bats appear to have lost the entire PYHIN gene family as a loss of function evolutionary event  containing gene family appears evolutionarily lost in bats, suggesting a dampened DNA-triggered inflammasome response as shown in ry event . The uniry event . Bats arry event . Therefory event . The losCytosolic DNA either produced from flight or viral infections imposes selective pressures on bat DNA sensors such as the PYHIN gene family mentioned previously. This results in a dampened sensing mechanism and downstream IFN production to avoid overreaction on a regular basis during flight or due to viral co-existence . While bRecently, developments from the Bat1k project which started back in 2017 have now published six near-complete annotated bat genomes. Through screening, they investigated gene loss, gain and selection to identify novel genes that are likely associated with viral tolerance within bats. These results will hence prove extremely useful in expanding existing knowledge of bat immunology within this fertile field of research . Upon peParvoviridae, Adenoviridae, and Bornaviridae which were found within the bats as well as other mammals, in addition to a partial filovirus EVE in Vespertilionidae. Retroviral protein-coding genes were identified to be highest from beta and gamma retroviruses as predicted by the project. It was also noted that in the genomes of some of the bat species, viral envelope-encoding DNA was identified that appeared more similar to alpharetroviruses, which had previously only been identified as endogenous avian viruses. Discovery of these alpharetrovirus elements within the bat genomes indicates that they must once have been infected by these viruses that appear originally avian in origin  NB which induced Mx1, OAS1 and PKR genes  also found an increased RNASEL level in the spleen following infection with Tacaribe virus, indicating that RNASEL induction in bats can be observed in vivo , which is not found in humans but is highly inducible in the black flying fox. RNASEL encodes a 2’5’-oligoadenylate synthetase-dependent RNase, which is a key protein in the antiviral response that degrades viral RNA in response to 2’5’-linked oligoadenylates produced by the OAS family of enzymes when stimulated by dsRNA from viruses . The ind in vivo . In huma in vivo . Other p in vivo . AdditioIt has been recognized that in IFN-stimulated cells, bat ISGs fall into two categories that share similar early induction kinetics but possess a unique late phase decline . These fUntil recently, bats have remained one of the least extensively studied mammals but have been proven as vital components in the transmission of many emerging and re-emerging diseases. With the recent COVID-19 outbreak originating from bats, it is now more important than ever to focus time and interest into bats as viral reservoirs to gain an understanding of their immunology in hope to reduce the emergence of new viruses from bats and manage their spread in future. Most bat species studied to date appear to share a myriad of immunological features with humans and other mammals. However, studies already conducted on bat immunity suggest that even though they share many key immune features to their human counterparts, bats also possess so-called “unique” immune characteristics and functional differences in the regulation of their innate immune system. It has been hypothesized that these unique immune features may allow bats to attain a symbiotic viral-host relationship whereby despite being infected with the virus, they do not display any clinical signs of disease and still retain the ability to transmit the virus to other species. Many hypotheses as to why studied bat species possess these novel immune characteristics refer to their novel behavioral features, such as flight capability, nocturnal activities, mating, and geographical distribution . These fin vitro experiments have proved successful in proving the identification of the bat IFN system and signaling, these results are not reflective of bats in the wild, as there are many discrepancies between the behaviors and characteristics of those observed in the lab in comparison to bats in their natural habitats. For example, it is critical to recognize that in the wild, bats, and other wild animals, are often infected with a multitude of viruses, bacteria, protozoans, and helminths. This heterogeneity is often lost in lab experiments. Thereby zoonotic viruses introduced to bats in natural conditions may face very different immune states to those conduced in a laboratory. Furthermore, many experiments conducted in the laboratory have used bat cells alongside human isolates of closely related viruses due to the inability to isolate most bat-borne viruses from their original source. These investigations demonstrated that infected bats do not develop the disease, causing speculations of bats as the reservoir hosts of the virus. Isolating the original bat-borne virus from the source species is required to provide a more reliable and definitive representation  (BB/M008681/1 and BBS/E/I/00001852) and the British Council (172710323 and 332228521).The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.


Our understanding of the behavioral and physiological mechanisms of monogamy largely comes from studies of behavioral interactions unique to pair-bonded individuals. By focusing on these highly marked behaviors, a remarkable conservation in the mechanisms underlying pair bonding has been revealed; however, we continue to know very little about the range of behavioral and neurobiological mechanisms that could explain the great diversity of pair-bonding phenotypes that exists both within and across species. In order to capture the dynamic nature of bonds over time and across contexts, we need specific, operationally-defined behavioral variables relevant across such a diversity of scenarios. Additionally, we need to be able to situate these behavioral variables within broader frameworks that allow us to interpret and compare patterns seen across species. Here I review what is known about behavioral synchrony with respect to pair bonding and discuss using synchrony as such a variable as well as a framework to expand on our understanding of pair bonding across timescales, contexts and species. First, I discuss the importance of behavioral synchrony and parental coordination for reproductive success in monogamous biparental bird species. Second, I highlight research documenting the critical importance of interpersonal coordination for human social relationships. Finally, I present recent work that experimentally bridges these lines of research by quantifying moment-to-moment behavioral synchrony during brief social interactions in zebra finch dyads. All together, these distinct perspectives support the notion that synchrony (1) is a shared premise for sociality across species, (2) is deeply shaped by social experiences, and (3) exists across timescales, behaviors, and levels of physiology. Conceptualizing pair bonding through the framework of behavioral synchrony is likely to facilitate a deeper understanding of the nuances of how social experiences and interactions impact the brain and behavior. The vasogaster) .Our ever-expanding understanding of the complexity of pair bonding is evident from the changing definition of monogamy itself. Traditionally, monogamy was used to describe partnerships in which individuals have a single, exclusive sexual partner, referred to as genetic monogamy . HoweverResearch on both the behavioral and neurobiological underpinnings of monogamy has contributed to our understanding of the great diversity in pair bond phenotypes. There is growing evidence that the neurobiological mechanisms supporting pair bonds change over time, particularly between formation and maintenance . More brThere are many challenges when it comes to extending our understanding of monogamy to encompass the diversity that exists across pair bonds. One challenge is that many of the highly marked behavioral variables described above are not applicable across species or contexts. An example of this problem across species can be demonstrated by attempting to apply behavioral variables from certain key model systems to other systems. For example, partner preference is a widely used behavioral metric for identifying monogamously bonded pairs; however, partner preference is not a clear indicator of pair bonds in all species . Rather,A second challenge is how to disentangle the role of parental behavior and biparental care from pair bonding. As indicated above, the extent to which parental duties are shared varies both within and across species. Furthermore, for species that form and actively maintain life-long pair bonds, pair-directed behavior during breeding periods and non-breeding periods can be quite different , thus itA third challenge comes from the fact that not all pair-directed affiliative behaviors are equal. This is true both with respect to the functional significance of affiliative behaviors for a pair bond as well as the value of a behavioral metric of pair bonding for researchers. For example, the same affiliative behaviors used to assess the strength or quality of a bond are also often used to identify the presence of a pair bond initially. By this reasoning, it may be assumed that strongly bonded pairs display more affiliative behaviors across domains. However, various disruptions  often affect one type of affiliative behavior and not another , or affeIn order to address these three challenges, we need to identify meaningful dependent variables that can be used to assess the dynamic nature of bonds over time and across contexts (both during breeding and non-breeding periods) and that can support comparisons across species. Because pair bonding fundamentally requires individuals to respond to and align with each other’s behavior, I have turned to behavioral coordination or synchrony as a fundamental behavioral “unit” necessary for understanding social bonding. Behavioral synchrony has specific operational definitions that may be applied across types of affiliative behaviors, timescales, and social contexts. More broadly, behavioral synchrony could be applied as a framework with which to interpret changes or differences in subtle aspects of pair-directed affiliation. Importantly, although behavioral synchrony has been studied across taxa, including insects, fish, birds, and mammals , researcBehavioral coordination is inextricably linked with sociality, and synchrony is a ubiquitous component of that coordination. Behavioral coordination/synchrony is essential for a wide range of behaviors including: schooling/flocking , group lbehavioral synchrony broadly to encompass the temporal and/or spatial coordination of behaviors as well as physiological and biological states during social interactions. In ethology, it has been proposed that behavioral synchrony has multiple components, including local synchrony (being in the same place at the same time), temporal synchrony (switching actions at the same time), and allelomimicry (engaging in the same behavior at the same time) . As witetronia) .Petronia petronia), biparental care is highly variable and typically one parent  will desert the brood at some point prior to the fledging of chicks. Pairs that do not desert, but remain together, appear to be more synchronized  and domestic geese (Anser anser domesticus), yearly patterns of circulating testosterone levels are correlated within a pair, and pairs with more coordinated patterns of circulating testosterone have greater reproductive success , and in species that actively maintain life-long pair bonds the synchronization of yearly patterns in circulating hormone levels within a pair is associated with reproductive success. In graylag geese  reproductive success is higher for pairs that have greater similarity in baseline corticosterone levels during incubation, but a greater dissimilarity in stress-induced circulating corticosterone levels during provisioning of chicks  parents, similarity in hormone levels (within the pair) does not appear related to reproductive success; although, individual hormonal levels are related to the expression of male and female parental behavior , parental coordination, and hormonal synchrony is to expose pairs to perturbations, disrupting levels of coordination between partners. In general behavioral disruptions are valuable in eliciting pair-directed behavior , 2016, aNymphicus hollandicus), a gregarious Australian parrot, the coordination of activities prior to breeding was associated with improved fecundity during subsequent breeding periods , an individuals’ contribution to parental care is associated with hormonal synchrony and relationship quality  (Cinclus cinclus) (Poecile atricapillus) (Erithacus rubecula) (Setophaga petechia)  ; white-tcinclus) ; black-capillus) ; Europeaubecula) ; yellow etechia) ], it seeWhile behavioral ecology research has largely focused on coordination of activities and movements across hours and days, research from psychology, sociology and anthropology, on humans has had a much stronger focus on moment-to-moment behavioral synchrony during brief social interactions. Such research has focused considerable effort on operationalizing and disentangling concepts associated with the emergent and dynamic nature of behavioral synchrony, or “interpersonal coordination” as it is commonly termed in humans. In human research, the notion that interpersonal coordination is used  to establish social bonds and connections has existed for over a century, at least since 1912  cited in. It has interpersonal coordination, [i.e., spontaneous coordination patterns between people during social interaction Simultaneous movement – this reflects the quantity or degree of movement that appears to begin or end at the same moment. For example, if a mother begins to turn her head at the precise moment that a child lifts an arm off of a table, it is an instance of simultaneous movement.(2)Tempo similarity – assume that all people have built-in tempos or speeds at which their behavior is set (much like the tempo an orchestra follows at a concert). Rate the degree to which the two people in the clip appear to be “marching to the beat of the same drummer.”(3)Coordination and smoothness – assume you are viewing a choreographed dance instead of a social interaction. How smoothly does the interactants’ flow or behavior intertwine, or mesh evenly and smoothly?As given in the rating from page 246 , and strangers . This isAcross contexts, interpersonal coordination has been shown to signal interest and positive affect ; facilitAs with other affiliative relationships in humans, romantic partnerships (pair bonds) are characterized by interpersonal coordination. Similar to the formation and maintenance of parent-offspring relationships, the formation and maintenance of romantic partnerships is also characterized by a concordance in behavioral and physiological synchrony  . InteresAnother useful comparison to understand the effect of romantic partnerships on interpersonal coordination comes from comparisons between romantic partners and strangers. Importantly, small differences in key aspects of micro-social interactions can have profound differences on physiological indicators of synchrony. Extensive bodies of work have described the role of interpersonal coordination in human social connections and relationships. Here I have highlighted (1) some of the complexities and nuances that exist in operationalizing, defining and scoring aspects of coordination, (2) the awareness humans have of the extent to which dyads are synchronized, (3) the pervasiveness of synchrony, not only as a behavioral expression, but also as a behavioral-physiological phenomenon at the level of a dyad or group, and finally (4) the effect of pair bonding  on interpersonal synchrony. For this last point, it is particularly important to note that during very brief social interactions subtle behavioral exchanges can have striking impacts on human connectedness. Again, I want to emphasize that while brain-to-brain coupling in humans is linked to pair bonding, this type of synchrony is not simply an intrinsic response to being bonded, rather it is developed and cultivated over time through repeated social interactions and can also be achieved through other mechanisms such as shared memory or immediate responses to narratives .Above I have discussed the extensive bodies of research from behavioral ecology highlighting the manner in which parental behavior is actively negotiated during brief periods of social interactions, suggesting that moment-to-moment behavioral synchrony may be a key aspect of monogamous partnerships. Furthermore, research from human psychology offers in-depth descriptions of how to conceptualize and operationalize moment-to-moment interactional synchrony and provides robust experimental evidence that behavioral synchrony during brief interactions is key to developing social connections and social bonds. Combined, the above two bodies of work raise the question of how moment-to-moment behavioral synchrony during brief social interactions is related to social bonding in birds and other animals.Now I turn to some of my recent research, in zebra finches, where I quantify multimodal patterns of behavioral synchrony during brief greets (or reunions). My aim was to describe how pair bonding influenced patterns of behavioral synchrony outside of a breeding context. Greeting (reunion behavior) represents a social situation that is relevant as pair bonds mature , as well as across social dyads (with pair bonded mates as well as other flock mates). Ultimately, greeting behavior may provide a relevant social scenario that could be compared across species. The two experiments I discuss below describe how behavioral synchrony (1) is affected by time (over the early stages of pair bonding), and (2) differs across social relationships.Zebra finches typically form life-long sexually monogamous pair bonds, but are also socially tolerant and breed and travel colonially . They enZebra finch pairs do not hold and defend territories, and they remain gregarious. Interestingly, in the absence of an opposite-sex partner they will form equally strong social bonds with same-sex conspecifics, and in the laboratory it appears individuals can also maintain multiple social bonds . BecauseGiven both the importance of behavioral coordination for monogamous partners during biparental care and the implication of behavioral synchrony broadly in supporting formation and maintenance of social relationships, one might predict that moment-to-moment behavioral synchrony is heavily affected by pair bonding. Furthermore, it would be natural to predict that behavioral synchrony is higher between monogamously bonded individuals than other social dyads. We tested these hypotheses by quantifying multimodal behavioral synchrony during brief social interactions (reunions or greets)  in zebraSimilar partner separation and reunion paradigms have been used in zebra finches previously , 2018. WAs described throughout this review, there are many ways to quantify the coordination or synchronization of behavior. For these experiments we (1) quantified the similarity in activity levels between individuals within a dyad, (2) calculated sliding correlation coefficients of time-stamped calls (and movements) as a quantification of the temporal synchronization within a dyad, and (3) conducted principal component analyses on activity levels and sliding correlations coefficients  to describe multimodal behavioral patterns.With respect to the first hypothesis, we showed calling activity during greeting behavior was highest during initial courtship, and there was a general pattern of decreased activity across the three stages of pair bonding  . Despiteper se modulates moment-to-moment behavioral synchrony.With respect to our second hypothesis, we found greeting behavior was affected by social relationship. Familiarity, particularly with females, resulted in more robust and more coordinated greeting behavior. More specifically, monogamous partners, familiar opposite sex dyads, and female familiar same sex dyads were more coordinated in both calling and movement, compared to novel dyads and familiar same sex male dyads  over time to other measures of behavioral and physiological synchrony between pairs. Here again, experimental approaches that quantify the effects of a disruption to partner coordination at one level  on other levels of partner coordination  , b, 2017There are many challenges when it comes to expanding our understanding of pair bonding to incorporate the diversity that exists in pair bonding phenotypes. These challenges are multifaceted, but include: (1) many of the highly marked behavioral variables used are not applicable across contexts and species, (2) the ultimate functions as well as the behavioral and physiological mechanisms underlying pair bonding are confounded with biparental care, and (3) not all affiliative behaviors are equally important. Among a number of possible approaches, one general solution to all three of these challenges is identifying behavioral variables that are relevant across species and contexts. Here I propose using behavioral synchrony as a fundamental aspect of broader sociality, through which we can gain a deeper understanding of the diversity of pair bonding phenotypes across species and contexts.Comparing patterns of behavioral synchrony in marked interactions of pair-bonded individuals  to behavioral synchrony in general social interactions (such as greetings) could offer a more detailed, nuanced portrait of the dynamic processes of social alignment. The patterns described in this review, including the role of active negotiation during brief social interactions on parental coordination, as well as the impacts of interactional synchrony on brain-to-brain coupling, suggest that behavioral coordination is seen across timescales and physiological levels. Thus, research on behavioral synchrony may prove invaluable for developing an understanding of how pair bonds change over time and are affected by social and environmental conditions. However, before comparing behavioral synchrony across contexts and species, further work needs to be conducted to determine how synchrony is related across behavioral-physiological levels. Importantly, such research needs to put synchrony within the context of pair bonding, and control for potential confounds that come from relating pair coordination to reproductive behavior. Such research lines will contribute to our understanding of whether moment-to-moment behavioral synchrony provides a basis for larger-scale behavioral alignment or vice versa.Pheugopedius euophrys), neural recordings have demonstrated that the partners’ synchronized vocal duet is associated with tight correlation in the partners’ neural responses in a cortical brain region associated with vocal-motor integration (When considering the interrelatedness of synchrony across behavioral-physiological levels, it is important to acknowledge that research on the neurobiology of behavioral synchrony is organized very differently than the research identifying neural circuits associated with social bonding. These two bodies of work offer very different perspectives on the neurobiological underpinnings of complex social dynamics. Research on the neurobiology of pair bonding has focused on identifying the key “players”: the brain regions, circuits, and neuromodulators that are implicated in the formation of a monogamous bond . Neurobiegration . It is pegration . It may egration . These aAt the beginning of this review, I suggested that it is easy to assume that behavioral synchrony is positively related to, and perhaps qualitatively unique in, monogamous partnerships. However, throughout this review i have emphasized that behavioral synchrony is critical for all types of social bonds. It is possible that there is something unique about how behavioral synchrony interacts with pair bonding. If there are unique characteristics of behavioral synchrony in pair bonded individuals, it is likely more nuanced than simply the degree of synchrony. For example, it is possible that monogamously bonded pairs more easily regain synchrony following a long-term separation, and/or that the consequences of disruptions to synchrony between partners are greater than disruptions to synchrony between non-bonded individuals. Again, detailed descriptions of brief social interactions and precise quantification and operationalization of behavioral synchrony are needed to determine whether there are in fact unique relationships between behavioral synchrony and pair bonding.Alternatively, it is also possible that there is nothing specialized about behavioral synchrony during pair bonding. Perhaps what makes pair bonds unique is simply the cumulation of unique shared experiences associated with courtship, biparental care, and long-term coordination of activities and movements. If behavioral synchrony is indeed not specialized in monogamous partnerships, this would argue for a shift in how we conceptualize monogamous partnerships: away from seeing them as extreme and unique social bonds, and toward recognizing that they exist along a continuum of varied social relationships.Combined, these data suggest that moment-to-moment behavioral synchrony is easily perceptible  and inforepeated social interactions and experiences and that bonds are co-created in the interactions between individuals, making them intrinsically emergent and dynamic in nature.Altogether, there is overwhelming evidence that “moments matter,” and that even brief social interactions can have profound effects on monogamous partnerships. The significance of this conceptual framework is a recognition that pair bonds, as well as of other affiliative bonds, are built upon The author confirms being the sole contributor of this work and has approved it for publication.The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.


Relationship between Household Chaos and Child, Parent, and Family Outcomes: A Systematic Scoping Review, presents the findings from 112 studies that assessed the influence of household chaos on a wide range of child outcomes. Findings highlight the various adverse child health outcomes across multiple domains that may be negatively affected by greater levels of household chaos including a few that reflect child health behaviors such as sleep, diet and weight gain. The review additionally presents findings from mediation and moderation analyses. This commentary highlights key aspects of the Marsh et al. review and outlines the implications of the work within health behavior research. This commentary further identifies child screen media use as a critically understudied area when considering the interplay between household chaos and child well-being.Household chaos, characterized by high levels of confusion, disorganization and hurriedness in the home, is increasingly recognized as an important risk factor for adverse child outcomes. Early research on household chaos and child well-being was largely within the field of developmental psychology, where greater levels of household chaos has been associated with greater behavioral, attention and learning problems in young children. The potential influence of household chaos on child health behaviors is more recently gaining attention within public health. A recent study by Marsh et al., entitled, the  There is a growing awareness that household chaos may negatively impact child development and well-being. Household chaos is characterized by high levels of confusion, disorganization and hurriedness in the home. While short-term bouts of chaos in the home are normal, chronic exposure to household chaos can have a profound impact on child development. Early research on household chaos and child well-being has largely been within the field of developmental psychology, and greater levels of household chaos has been associated with greater behavioral, attention and learning problems –4 in youBMC Public Health, Marsh and colleagues [In an article published in lleagues  promote lleagues  The MathOverall, findings demonstrated that household chaos was associated with multiple adverse child outcomes including those aligned with health behavior research such as increased weight status, poor sleep and poor dietary behaviors. For example, greater levels of household chaos was associated with greater self-reported barriers to preparing meals at home among parents, less availability of healthy food at home, and fewer meals together as a family in a sample of 819 households with young children . HousehoA particularly interesting aspect of the Marsh et al. review is that findings suggest household chaos may act as a mediator of the relationship between risk factors and adverse child outcomes. Sixteen studies included in the review assessed household chaos as a mediator and findings largely supported partial mediation. For example, the detrimental effect of low household income at age 2–3 years on emotional problems at age 7–8 years was partially mediated by higher household chaos at age 4–5 years in a study among children as they aged from 2 to 8 years . ConversThe implications of the research on household chaos span across multiple disciplines including public health. Clinicians and child health advocates should consider the influence of household chaos on child well-being when interacting with families in a clinical setting or when advocating for programs and policies to reduce the burden highly chaotic homes may uniquely face. Health behavior researchers additionally should consider the role of household chaos when examining risk factors for suboptimal child health behaviors, including poor diet, obesity risk, screen use, short sleep and substance use. Importantly, the design of health behavior interventions should consider the capacity of highly chaotic homes to adhere to intervention activities. For example, how can incentive programs be designed to best support chaotic homes marked by a lack of structure and routine?The availability of validated scales of household chaos enables researchers to identify families that likely need additional support in adhering to health behavior interventions. It is important to note that the available chaos scales are not diagnostic, and currently no threshold exists to define a chaotic versus a non-chaotic home. However, routinely including household chaos measures in behavioral intervention studies and using standardized scoring metrics can help identify families at risk of non-adherence. It will also be important to identify if household chaos is a mediator between socio-demographic characteristics, such as lower household income, and parent or child adherence to health behavior interventions. That information will help avoid generalizations about socio-demographic risk factors and child health, and findings can inform the design of support systems to appropriately help families in their efforts at health behavior change.The review by Marsh et al. also highlights areas within public health that should further investigate the role of household chaos on child well-being. For example, research on household chaos and digital media use among children is scant , 14. TheIn summary, household chaos appears to be a unique construct that is associated with multiple areas of children development, health and well-being. Health behavior researchers should consider the role of household chaos on adverse child outcomes and consider the influence of household chaos on a family’s ability to adhere to health behavior interventions. Future work is needed to standardize findings across available studies to more comprehensively understand the influence of household chaos on child well-being across multiple domains. Regardless, current findings highlight the need to consider household chaos when assessing child well-being and provide the impetuses for future studies to assess causal associations.


Navigation is an essential activity of everyday life, related to both work, and leisure. For some populations with certain neurocognitive issues  or characteristics , navigation is fundamental to their autonomy and access to the community. It is a complex activity that entails several stages, from planning a route to reaching a destination ; also comparing them with those with attention deficit hyperactivity disorder [ADHD]; Farran et al.); individuals with Down syndrome , known to have stronger spatial than verbal abilities; individuals with autism spectrum disorders  whose profile in the spatial domain varies. Some contributions examined adults with a cognitive disability  who can have difficulty navigating due to their impaired intellectual functioning; and Korsakoff patients, whose memory disorders also affect their recall of spatial information .With a collection of 15 studies, this special issue advances our knowledge of some navigation and related aspects. Several atypical development (AD) populations are examined in this issue, including: children and adults with William syndrome (WS), who are known to have stronger verbal than spatial abilities (Muffato and De Beni) or those with impairments. Elderly people with vascular cognitive impairment (VCI), who have specific egocentric representation difficulties due to their parietal deficit, are compared with cases of early-stage Alzheimer's disease, whose temporal deficit causes specific allocentric representation difficulties . These studies mainly examined the allocentric versus egocentric properties of environmental representation using virtual environments , videos of real environments (Muffato and De Beni), or real path learning . Some studies used spatial tasks to assess navigation-related aspects, such as perspective taking , route planning , and the peripersonal space , or conducted semi-structured interviews on how respondents solved everyday navigation issues . Two papers focus on individuals with brain lesions: one profiles the navigation-related difficulties of two right-brain-damaged patients using several small- to large-scale tasks ; the other concerns an imagery-based rehabilitation program for a patient with right temporal lobe damage suffering from topographical disorientation . Two other papers examine blind people and the use of haptic aids, one during navigation  and the other for exploring a map before navigating in a real-world setting . Finally, two papers assess the malleability of healthy individuals' navigation skills: one involves specific training based on exploration, moving from small areas to larger and more complex environments ; the other specific training on the use of egocentric and allocentric navigation strategies . These findings offer insight into potential rehabilitation programs for individuals with navigation difficulties.Other papers examine healthy older adults . Allocentric properties pose more of a challenge, with evidence that allocentric representation is no more impaired in AD than in VCI , and can be facilitated by a structured environment . Mental representations of spaces and environments seem to be supported by general cognitive functioning (as seen in older adults), visuospatial abilities such as mental rotation, VSWM, and the self-reported pleasure people experience when exploring an environment . Motor abilities seem to support spatial performance too, as seen in ASD , but this relation was not found in individuals with WS or ADHD . In semi-structured interviews, disabled people reported getting lost more frequently in complex environments, and having to ask others for help .Although different aspects of navigation are examined, each of these studies uses different methods and considers specific populations. The results of these studies indicate that different populations  can mentally represent spaces and environments with egocentric properties , or presenting vibro-audio maps before navigating . A case study contribution explores route planning difficulties in a patient with an occipitoparietal lesion, but not in a patient with a temporoparietal lesion , shedding light on the neurocognitive mechanisms involved in navigation and related aspects of wayfinding. Finally, results obtained with training reveal that navigation skills are malleable, enabling more efficient strategies to be learned such as changing from an egocentric to an allocentric approach , and enabling even those with topographical disorientation to navigate successfully .Studies that have examined visual impairment with blind participants have shown the benefits of innovative haptic sources, such as using vibratory signals via a hip-worn belt to navigate, especially in typically noisy everyday environments (To conclude, this special issue expands our understanding of navigation abilities in populations with different characteristics, and how they can be improved by appropriate intervention. Overall, it offers insights that will prompt us to continue to investigate navigation abilities, taking up the challenges faced by different populations and enabling us to create living environments that are more inclusive and accessible.All authors listed have made a substantial, direct and intellectual contribution to the work, and approved it for publication.The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.


Termite mounds are fascinating because of their intriguing composition of numerous geometric shapes and materials. However, little is known about these structures, or of their functionalities. Most research has been on the basic composition of mounds compared with surrounding soils. There has been some targeted research on the thermoregulation and ventilation of the mounds of a few species of fungi-growing termites, which has generated considerable interest from human architecture. Otherwise, research on termite mounds has been scattered, with little work on their explicit properties.This review is focused on how termites design and build functional structures as nest, nursery and food storage; for thermoregulation and climatisation; as defence, shelter and refuge; as a foraging tool or building material; and for colony communication, either as in indirect communication (stigmergy) or as an information channel essential for direct communication through vibrations (biotremology).Our analysis shows that systematic research is required to study the properties of these structures such as porosity and material composition. High resolution computer tomography in combination with nonlinear dynamics and methods from computational intelligence may provide breakthroughs in unveiling the secrets of termite behaviour and their mounds. In particular, the examination of dynamic and wave propagation properties of termite-built structures in combination with a detailed signal analysis of termite activities is required to better understand the interplay between termites and their nest as superorganism. How termite structures serve as defence in the form of disguising acoustic and vibration signals from detection by predators, and what role local and global vibration synchronisation plays for building are open questions that need to be addressed to provide insights into how termites utilise materials to thrive in a world of predators and competitors. Consequently, past research was mostly concerned with autonomous nest constructions or building activities, the network structure of tunnels, and aspects of stigmergy and self-organisation Noirot and Darlington Stigmergy, hereby defined as indirect communication modification of the environmentdirect communication is provided by optical, pheromone, tactile and vibrational information We hypothesise that biotremology is not only used to determine food size 2thermal envelope – a hard outer shell as general protection, for defence against predators and protection against desiccation – and a heterogeneous thermal inertiaMacrotermes michaelensi, and (b) Coptotermes lacteus. M. michaelensi is a member of the subfamily Macrotermitinae (the fungus-growing termites) in the family Termitidae or the higher termites. Many species of higher termites build mounds, of varying size and design; and much of the research into termite mounds has been conduced on M. michaelensi. It is African and is found primarily in savannahs, with complex nest constructions, including a turret which contains an intricate system of conduits for climatisation, fungus combs to decompose lignin and cellulose, nurseries and a central royal chamber Coptotermes lacteus is a member of the subfamily Heterotermitinae, in the paraphyletic family Rhinotermitidae, one of the lower termites. It is of interest because it  are the only lower termites to build mounds Termite nests are made of an homogeneous 2.1Macrotermes spp. and Odontotermes sp. (both Macrotermitidae), and in forests, specially Cephalotermes rectangularis . These mounds generally have an (undifferentiated) alveolar structure, with external shell and laminar internal structure A systematic study of general principles of construction as found in termites of the savannah or the forest has never been attempted and it remains debatable whether general patterns and structures exist. Termite nest geometries and builds appear to be largely variable, even among the same species, but those in forests of the same species are on average smaller and more variable in shape and location than in savannahs Macrotermes natalensis) to southern Asia (Odototermes obesus); many species are mound builders, and many of these have been studied in some detail , which is for some species also used to store foodMacrotermes natalensis or Macrotermes michaelensi; the channel system is called exoecie if it is detached from the nesting structure as in case of Tumulitermes spp. Macrotermes species. In Thailand, M. gilvus mounds have a simpler structure, without obvious ventilation passages; indeed large colonies appear to occupy a smaller proportion of their mounds perhaps due to ventilation issues The fungus growing Macrotermitinae are distributed from central Africa  Cryptocercus. Some species, such as Reticulitermes flavipes or Reticulitermes grassei, start as single-piece termite, then move on to other pieces thereby repeating evolution – the latter being also able to build internal walls Coptotermes acinaciformis, for which the Southern form houses within the stem of a nesting tree, while the Northern form designs mounds adjacent to a foraging tree , comprising more than a quarter of all termite species, often build hypogeal nests Nasutitermes eucalypti or more often Macrognathotermes sunteri (both Termitidae), which are inquiline to and eat the mound of Coptotermes acinaciformis, tunnel corridors in nest portions of their host, which sometimes form discretely attached mounds, cf. Humus (or soil) feeders found mostly in tropical forests or savannahs  Nest, nursery and food storage, (2) Thermoregulation and climatisation, (3) Defence, shelter and refuge, (4) Termite clay as building material and foraging tool, and (5) Stigmergy and communication channel.3.1Coptotermes acinaciformisThe common digestion of plant fibres in lower termites is based on symbiotic interrelationships with various gut microorganisms  Cubitermes- (Ophiotermes-) group CubitermesThe pre-digested lignocellulose may especially attract commensal species, inquilines or kleptoparasitic termites (mound-/soil- or humus-feeding species) such as Higher termites of Macrotermitidae make use exosymbiotic relationships to Termitomyces strains to break down lignocellulose, including lignin, by cultivating fungus in fungal gardens – an ability of the fungus due to co-evolution which made switching between multiple termite hosts difficult Sphaerotermes sphaerothorax is a bacterial farming species which builds to two kinds of combs: the first one is made of an accumulation of faeces in the lower part of the subterranean nest (dark colour), the second kind is either made of mylospheres or buccal pellets; after bacterial action , Sp. sphaerothorax consumes the fermented (lighter coloured) pellets Other higher termites belong to non-fungus-farming species which grow complex structured bacterial combs by accumulation of pellets, as an evolutionary adaption of carton material to external rumen and which is assumed to allow the need for the removal of gut protist symbionts 3.2Macrotermes bellicosus the inner nest – the coolest part during the day °C with a humidity “near saturation” Termites are known for their thermoregulation, but only a few examples have been systematically studied . Especially for those species homeostasis, i.e. air-exchange, temperature and humidity control via ventilation is important for the development and against desiccation of the colony, especially that of the brood (immature instar stage) Macrotermes spp. and Odontotermes spp. are considered either open or closed ventilation systems Macrotermes bellicosus the ventilation system is closed in West Africa Guinean region, but open near the base of the mound in Uganda, Congo and Western Kenya The epigeal nests of African and Asian Trinervitermes geminatu have closed, micropore-perforated outer walls for efficient gas exchange and water drainage Open systems exchange gas through air flow velocity differences, either caused by steady forcing (e.g. convection currents due to metabolism) or by transient processes  2 diffusion and air rises upwards in the channels directly behind the outer wall and downwards through the central shaft Thermoregulation in a termite mound is interesting due to its working principle. Similarly to a thermosiphon (evaporative cooling) methanogenesis in their hind gut, up to half of the emitted The metabolism of termites in the mound plays an important role in gas circulation and thus for the thermoregulation in the mound. The production of metabolic gases has been well studied with estimates of gases corresponding with colony size of intact mounds in the field, cf. Odontotermes obesus in Africa have Macrotermes michaelensi and M. subhyalinus average −1) Coptotermes lacteus with around eight times normal atmospheric Termite mounds may experience high concentrations of Zootermopsis nevadensis) Termites exhibit high tolerance to fluctuations of gas composition and to very high concentrations of carbon dioxide (and low oxygen levels) which would easily narcotise other insect species  against an opponent, such as intruding predatory ants Incisitermes minor. Prohamitermes mirabilis uses prefabricated plugs made from a small foreign particle (sand grain) wrapped with nest cement, but larger than the entrance to the chamber, to seal off nest chambers which commonly only have two small holes in the side walls In fact, most termite defensive action originates from passive means by staying camouflaged , which is far from intuitively obvious Nasutitermes spp. are perfectly adapted in coloration to the underlying stem, resembling in shape bizarre lumps as found after a trauma of the tree as a consequence of a healing process, in burls (triggered genetic predisposition) or as a consequence of certain  tree diseases (e.g. black knot) Camouflage is the most prevalent Cubitermes sp. nest using methods from graph theory, paths were found to be much shorter than would be expected if adjacent chambers were simply randomly interconnected However, the tunnel system structure and the tunnels' lengths are influential in the effectiveness of defence of a colony. Outside the nest, termites invest lots of energy to stay cryptic within their gallery system and use soil bioturbation against predation 3.4Sphaerotermes sphaerotorax) use homogeneous mixtures of clay and fine sand particles, which is a different composition from the coarser soil around the nest Labiotermes labralis are alveolar carton material nests, strong, robust and heavy, and all nest parts can contain visible traces of sand, while hypogeal nests of L. longilabius are composed of tiered, flat chambers, a recurrent morphology in Syntermesinae nests Termites use different building materials in their mound and galleries with a range of properties Arboreal nests consist of exogenous lignocellulosic materials  and have fewer inorganic components Macrotermes bellicosus) and its aggregate stability after heavy rainfalls increases Odontotermes nr. pauperans (Macrotermitidae) prefer fine silts and clays for fungus comb walls and inner nest gallery construction over coarse silts and sands as found in top soils Polyrhachis sokolova, Forel  are often composed of soils from non-surface soil layers including 47% kaolinite (at ca. 228  mm depth), 23% boehmite (at ca. 315  mm) and 10% gibbsite (at ca. 110  mm) Especially for the royal cell, clay soils from deeper layers are the preferred building material due to their greater water-holding capacity Tumulitermes tumuli mounds contain gold particles found at 1 m to 4 m depth Nasutitermes longipennis build the external part of the nest in “sand and clay” cemented with stercoral mortarTermites have been found to dig much deeper. There has been some interest in using epigeal termite mounds for sampling minerals found at greater depths, especially for gold exploration. Sampling termite mounds on the surface is considerably faster and cheaper than drilling, cf. Odontotermes obesus. Boluses ,  and  respectively Overall, the porosity of the outer wall of termite mounds decreases but the microporosity of less than 0.1 μm pore size 5 μm  increaseCoptotermes acinaciformis builds structures in a dynamic process as a foraging tool to reinforce load-bearing clay walls to access otherwise inaccessible food Coptotermes acinaciformis to hold a specific load was about 0.22 MPa Odontotermes obesus mound walls are up to 1.8 MPa for the outer shell Termite constructures of clay and lignocellulostic cement can have considerable strength, in mounds but of particular interest are other applications. For example, 3.5In his seminal paper, Grassé (1959) Stigmergy can be subdivided into qualitative (self-assembled dynamics) and quantitative (self-organised dynamics) aspects In many early studies on stigmergy based on ants, pheromones and optical cues construction pheromones), which are supposedly left in boluses and act as short range navigation feedback while trail following pheromones act as long range navigation feedback; random walk processes are caused by termites staggering off The processes of termites building have been studied by Deneubourg There is increasing evidence that termites us other information. Not visual information as termites are blind and there is no evidence that termites perceive drumming signals via airborne sound 4As outlined above, there is variable depth of the state-of-the-art knowledge about the various functionalities of termite structures and there is a lack of systematic studies to allow general features and differences to be classified. Here we will discuss and identify key research topics that will potentially answer the question on the holistic picture of the interrelationship between termite structures, termites and their behaviour as a superorganism.While bees or ants would survive without their nest for some time, termites would be exposed to the twin dangers of desiccation or predation Pheromones and self-organisation revisited. The building process rather than the built structure has been the centre of interest Cubitermes spp. well-connected, the essential enabler to successfully use gypsum in endocasts. The connectivity of the tunnels and nodes (chambers) is attributed to a sub-function of defence or climatisation – the assumption that the tunnel system and digging activities follow diffusive processes or resulting in tree-like shapes seems to be a convenient simplification, the truth might yet lie somewhere in-between, with stronger emphasis on determinism, i.e. defined functionality of engineered structures.While there is largely consensus that group level patterns emerge from interacting individuals following simple behavioral rules , stigmergic building processes presumably originate from a cement pheromone. Yet, since termite mounds seem to grow in discrete stages, it has been argued, that a general continuous  growth model based on molecular diffusion of pheromones through the mound wall can be excluded Biotremological signals. Recently, the action of digging and the aggregation of termite workers have shown a strong effect on recruiting termites for excavation and building work as information, though, cannot be the only factor since termites within the nest walk and live next to each other which also leaves traces and signals Random walk or swarm behaviour models, widely applied in computer science, seem debatable in light of the eusociality of termites, which follow explicit cues and directed signals M. michaelseni to intraspecific competition for foraging areas; it may be assumed that communication and eavesdropping are significant in colony survival. Evans et al. Cryptotermes secundus eavesdrops on the dominant subterranean termite species Coptotermes acinaciformis to choose smaller pieces of wood to avoid competition; similar strategies – a preference for distinct diets to avoid conflicts – have been found in many neotropical termite cohabiting builder- and inquiline-species-relationships, cf. Macrognathotermes sunteri are very quiet, and their walking cause less vibrations than its host species, Coptotermes acinaciformis, resulting in the so-called disguise in the form of insignificance as a special mechanism of camouflage Grohmann et al. Considering that biotremology plays a central role in termite communication Synchronisation of vibrational information might be more important to building and nest growth, triggered initially via localised individual action which may lead to global collective behaviour. The termite nest would act as a both a communication network and a large vibration sensor; locally constrained, vibrational signals and cues would provide subnetworks with synchronised tasks clearly defined via transmission through the structure. Studying the mechanical composition  and their compound properties would enable a deeper understanding of how termites modify their surroundings – which should be crucial for their eusocial character and the information exchange (from nestmate interaction to synchrony) required to run a colony of several million individuals.Since biotremology has been shown to be significant in termite colony organisation, local and global synchronisation rather than stigmergy could be the prevalent trigger for building activities and the reason for group-level pattern emergence; this remains to be determined Understanding the structure. Until recently the galleries of ant and termite nests have been studied using endocasts, e.g. gypsum, dental plaster or lead Cation-adsorbing capacity provides “expandable clays” as a surface chemical or surface complexation process to facilitate the exchange of chemical species between an aqueous solution and mineral surfaces present in geological porous formations The techniques used to visualise the nest as well as analysis methods applied to study complex structures have been identified as being problematic Sebastian Oberst: Conceptualization, Methodology, Investigation, Funding acquisition, Resources, Writing - original draft, Writing - review & editing, Visualization, Project administration. Joseph C.S. Lai: Conceptualization, Writing - review & editing. Richard Martin: Writing - review & editing, Visualization. Benjamin J. Halkon: Writing - review & editing, Funding acquisition, Resources. Mohammad Saadatfar: Writing - review & editing, Resources. Theodore A. Evans: Conceptualization, Writing - review & editing, Funding acquisition.The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.


Arthritis is a term used to indicate joint pain that are caused by inflammation of joints or joint disease that occur commonly among older people. People of all ages, sexes and race can and do have arthritis as well. There are different types of arthritis with different causes and treatment methods but the most commonly known are the Rheumatoid Arthritis (RA) and the Osteoarthritis (OA). The symptoms of arthritis are joint pain, swelling, stiffness and decreased range of motion which could develop over time or appear suddenly. These symptoms may or may not exacerbate over time. As the disease get more severe, it could prevent patients from doing daily activities such as walking up the stairs and experience chronic pain .in situ hybridization (FISH) analysis have been widely used at the cellular level to detect expression levels and cell distribution of mRNA [There are multiple approaches for diagnosing arthritis other than performing physical examinations by the doctor or rheumatologists. Conventional radiography (CR) is one of the many imaging methods for diagnosis. CR is cheap compared to the alternative, magnetic resonance imaging (MRI) and faster than ultrasound. However, CR can only be used towards the end of the disease process, where the bones have eroded and joint spaces narrowing  and it d of mRNA .Examples of contrast agents are the super paramagnetic or paramagnetic metals, such as Gadolinium Contrast Medium, used in MRI that mainly observed the whole-body scan. To get a more target specific imaging, molecular imaging such as PET and optical imaging like fluorescence microscopy are used for their sensitivity and specificity for target detection. However, the disadvantages uses of PET are that they have poor spatial and temporal resolution. They also require radioactive compounds that have intrinsically limited half-life which limit their repeated use due to safety regulation ,10. In tin vivo medical imaging. Despite countless of organic dyes in the market for research, there are only two fluorophores that’s approved by the US Food and Drug Administration (FDA) for medical use, which are the fluorophores are indocyanine green (ICG) and fluorescein [In the past few centuries, there was a surge in the use of fluorescent dye in various areas. Special dyes are used for printing valuable documents such as money, and certificates. Some dyes are used to aid in leak detections of oils and fluids in vehicles. Because of its distinct ability, the dyes are also used to assist in exploration of water underground. Using similar concept in large scale, researchers started to apply this approach in orescein –13. ICG Fluorescence microscopy, providing real-time visualization in the surgical field, has similar sensitivity to radionuclide imaging, providing high resolution, high contrast, high specificity and quantitative of the sample. The downside of optical imaging is that uncertainty emerges as the scans get into deep tissue due to unpredictable light scattering and absorption ,15. HencTo obtain a successful optical molecular probe for medical imaging, the right wavelength must be employed to excite the dye to obtain a unique emission wavelength. However, if the excitation wavelength is near the ultraviolet region, the tissue will be damaged, while excitation on at the infrared region will cause tissue heating. Absorbance and auto fluorescence could be observed in any case when there is asymmetrical stokes shift . To previn vivo leukocyte cell can be tracked by using optical imaging techniques. These in vivo leukocyte cells are labeled with fluorescent dyes, which are suitable for the detection of synovial inflammation in an antigen-induced arthritis model [Previous study of OI have shown promising results after injection of fluorescent dyes for detection of arthritis ,5,22,23.There are few available fluorescence-based imaging techniques: fluorescence microscopy, flow cytometry, cell sorting fluorescence correlation spectroscopy as well as particle tracking velocimetry .in situ hybridization (ISH) using probes with multiple fluorophores or multiple probes with one fluorophore [in situ, enabling genotyping of individual transcript molecule. The earliest single molecular RNA imaging studies was transcribed and fluorescently labeled in vitro [in situ Hybridization (FISH) can differentiate RNA molecules with just a single base because it only binds to specific parts of the nucleic acid. FISH are convenient procedures due to its highly sequence-specific when combined with amplifications during procedures in fixed cells [The localization of mRNA in cell has been around since 1980s, but then, mRNA translation could only be visualized via orophore . The groin vitro . As seened cells ,27. Not Molecular beacons (MB) have been used in variety of applications involving real-time mRNA detection in living cells , DNA-RNAAn example for the success of molecular beacon is explained in a paper published in 2011 by Bratu et al. . MoleculUpon the success of molecular beacons for fluorescence optical imaging, another research group have developed ratiometric bimolecular beacons (RBMBs), to scan the directed transport of single engineered RNA transcripts in living cells in real-time in 2013. These RBMBs are designed to overcome the hurdles posed by conventional MBs and to improve signal-to-background ratio . When unThis design was hypothesized to reduce level of false-positive detected for 24 h compared to the conventional MBs. The unquenched reference dye is acting like a control to allow measurements of the reporter to be adjusted for differences in RBMBs delivery leading to more precise measurement of RNA hybridization. Their conclusion in this study that RBMBs may be the tools to analyze single engineered RNA transcripts in living cells.A different approach to increase fluorescent signal upon bonding is to use forced intercalation (FIT) probes as seen in in vivo targeting and imaging, QDs are also used in cellular targeting and imaging, as well as fixed tissue analysis, optical encoding and quantitative determination [Quantum dots (QD) are a new class of fluorescent probes starting to emerge in the past few decades. QDs also have long lifetime increasing the probability of adsorption and producing broad absorption spectrum. Other than being non-toxic to samples, one of the most appreciated advantages of QD is their photostability or resistance to photobleaching, which allows images to be recorded over a longer period compared to conventional fluorescent dyes . Other tmination .in vivo imaging. However, parameters such as the distance between gold nanoparticle to optical absorbance and scattering intensity of the inter-particle distance can be controlled, resulting in a research group utilizing 20 nm Au nanoparticles QD to predict the localized surface plasmon resonance (LSPR) of gold nanoparticles. They were able to synthesize 20 nm AuNP monomers with zero LSPR background as probes with only a single target molecule required to form a dimer with significant plasmon resonance coupling effect, increasing the sensitivity of the LSPR sensor to single cell level. In their study, they were able to present a smart single mRNA imaging approach in living cells based on target-induced formation of nanoparticle dimers. They concluded that with proper linker, these nanoparticles could serve as a basis to many imaging techniques for biomolecules and mRNA in living cells [Size of the quantum dot nanoparticles in bioimaging field generally falls within 2–10 nm in diameter. QDs have unique optical and electronic properties, with molar extinction coefficients that are 10–50 times larger, making it much brighter than conventional dyes. The emission wavelengths are size tunable depending on the radius of the QD. Larger QDs were also synthesized to be used in other applications other than ng cells .The optical properties of quantum dots originated from their elemental composition, with a semiconductor core such as cadmium selenide (CdSe) or lead selenide (PbSe), coated with a semiconductor shell, as seen in Since quantum dots have become interesting fluorophores for biological imaging fields, researchers have developed a new method for the fluorescence imaging of endogenous mRNA using signal-tunable molecular beacon technique based on QDs in living cells. As seen in in vivo imaging mainly due to overlapping fluorescence emissions. Different approaches have been executed, including the recently developed 3’untranslated region (UTR)-based reported gene imaging system to monitor the expression of patterns of mRNA. However, with this approach, it is difficult to differentiate if the data obtained are from the mRNA expression or from cell death in vivo [There are many restrictions obtaining multicolor  in vivo –47.On the other hand, different fluorophores with discernable emissions wavelength must be chosen for multicolor imaging. The complications for the traditional dyes such as organic dyes and QDs are the requirement to use UV or short-wavelength radiation for excitation of the materials and their cytotoxicity in biological environment. Low light penetration depth is observed due to the short wavelength excitation light or low signal-to-noise ratio due to auto-fluorescence. Although fluorescence-based imaging techniques have improved tremendously, there are still rooms to improve the techniques or the probes. It is important to develop more efficient bio-labels to overcome these limitations. NIR probes have gained its momentum the past decades to overcome the shortcomings of the traditional probes when it comes to monitoring the sample with higher depth. Few companies have developed some NIR fluorophores with emission >800 nm, permitting NIR probes to be used together with the original fluorescent organic dye . With thThe NIR dye, ICG, is already being used to test for liver cancer during surgery, to identify small and unidentifiable liver cancers in real time. ICG has also been used to identify lymph nodes in real time in a small number of breast cancer patients . Even thIn summary, this review analysis on the visualization of mRNA with different hybridization techniques. There were many shortcomings since the development of fluorescence-based imaging techniques, but scientists and researchers have all overcome the obstacles and improved both the probes and instruments for a better future. The capability of fluorescence-based imaging techniques is open to new possibilities for better and faster diagnostic of joint diseases in the future.


Across college campuses, the prevalence of clinically relevant depression or anxiety is affecting more than 27% of the college population at some point between entry to college and graduation. Stress and self-esteem have both been hypothesized to contribute to depression and anxiety levels. Although contemporaneous relationships between these variables have been well-defined, the causal relationship between these mental health factors is not well understood, as frequent sampling can be invasive, and many of the current causal techniques are not well suited to investigate correlated variables.This study aims to characterize the causal and contemporaneous networks between these critical mental health factors in a cohort of first-year college students and then determine if observed results replicate in a second, distinct cohort.Ecological momentary assessments of depression, anxiety, stress, and self-esteem were obtained weekly from two cohorts of first-year college students for 40 weeks (1 academic year). We used the Peter and Clark Momentary Conditional Independence algorithm to identify the contemporaneous (t) and causal (t-1) network structures between these mental health metrics.P<.001 unless otherwise stated. Depression was causally influenced by self-esteem  and itself  in both cohorts. Anxiety was causally influenced by stress , self-esteem , and itself  in both cohorts. A causal link between anxiety and depression was observed in the first cohort  and only observed in the second cohort with a more liberal threshold . Self-esteem was only causally influenced by itself . Stress was only causally influenced by itself . Anxiety had positive contemporaneous links to depression  and stress . Self-esteem had negative contemporaneous links to each of the other three mental health metrics, with the strongest negative relationship being stress , followed by depression  and anxiety . Depression had positive contemporaneous links to anxiety (previously mentioned) and stress .All reported results are significant at This paper is an initial attempt to describe the contemporaneous and causal relationships among these four mental health metrics in college students. We replicated previous research identifying concurrent relationships between these variables and extended them by identifying causal links among these metrics. These results provide support for the vulnerability model of depression and anxiety. Understanding how causal factors impact the evolution of these mental states over time may provide key information for targeted treatment or, perhaps more importantly, preventative interventions for individuals at risk for depression and anxiety. Worldwide, depression is estimated to affect over 300 million individuals, and anxiety is estimated to affect over 260 million individuals . A recenTwo factors that may precipitate anxious or depressive symptoms are increased stress and low self-esteem ,7-10. BeIdentifying temporal patterns of occurrence and causal factors underlying these mental disorders will be critical to addressing the growing mental health problems on college campuses and elsewhere. An unresolved question is the exact nature of causal relationships between the four variables previously mentioned. Although multiple definitions exist for these constructs, we focus on a subset of these, so they can be surveyed frequently and with minimal effort needed by the subject. Stress can be defined as a negative emotional or physical experience that has subsequent physiological or behavioral changes directed toward adaptation, either by changing the situation or accommodating its effects . In thisThere are a variety of models that predict how these variables influence each other across the lifespan. Data supporting these models have generally been sparsely sampled, with weeks or months separating 3-5 waves (time points) for each survey ,16. HereIncreasing the sampling rate and study duration compared to previous causal studies would provide unique insight into the relationships among these mental health metrics. Recent technological advances allow for more frequent sampling with ecological momentary assessments (EMAs), which can be less invasive and more naturalistic than typical laboratory-based studies if the sampling frequency is not burdensome. With EMAs, questions can be sent directly to a person’s smartphone as often as desired ,26. EMA The ability to sample individuals’ mental health metrics more frequently allows for the possibility of testing models and theories present in the psychological literature, as well as generating new ones. With larger amounts of data, more methods to analyze causal influences can be considered. Autoregressive models such as Granger causality can be used to assess aspects of causation in an observed system . NotablyAlthough many research groups have demonstrated that stress, self-esteem, anxiety, and depression are all correlated, an unresolved question is if there are causal influences between these variables. A variety of psychological models related to interactions of these mental health metrics have been proposed, but much of the extant literature does not have temporal frequency and the total number of time points required to perform many of the recently developed causality methods. In this study, we aim to characterize the causal network of relationships between stress, self-esteem, depression, and anxiety as assessed by EMAs collected through the smartphone app, StudentLife. We first test this in a sample of first-year college students using PCMCI, then retest the same analysis in a completely independent cohort of subjects. Subsequently, we attempt to determine which psychological models of anxiety and depression best fit the current results and discuss possible implications.Participants were first-year undergraduate students with eligible smartphones recruited from the Dartmouth College community during their first academic term. The Committee for the Protection of Human Subjects at Dartmouth College approved this study. Each participant provided written informed consent in accordance with guidelines set by the committee and received their choice of either course credit or monetary compensation (US $10 per week of EMAs answered) for study participation . A subsaBrief surveys of depression, anxiety, stress, and state self-esteem were assessed for 40 weeks (1 academic year) using EMAs , a methoThe goal of the current work is to determine the causal and contemporaneous network structure among the mental health metrics collected on a weekly basis. Contemporaneous network structure is the relationship between variables within the same time point, while causal network structure is the relationship between variables at different time points. PCMCI has the advantage of being able to recover causal networks that include multiple sources of causation and is suitable for data sets with missing responses and correlated variables ,29,35. PCondition selection is a method to reduce the number of network connections that are interrogated for causal influences. Condition selection identifies nodes from previous time points that are likely to be real connections. Condition selection is the first phase of the PCMCI algorithm implemented in Tigramite  and is pMCI, the second step of PCMCI, identifies contemporaneous and causal relationships from the reduced set of connections passed to it from the PC1 algorithm. Contemporaneous relationships are those that occur at the same time or faster than the sampling rate (within the same week in this study) and directionality cannot be assessed. Causal relationships are those that occur across time points (between weeks in this study). MCI was implemented through partial correlation estimated with a linear ordinary least squares regression and a test for nonzero linear Pearson correlation on the residuals at an alpha of .005. By using condition selection (PC1) paired with MCI using the partial correlation test, this method is able to account for autocorrelation, leading to well-controlled false-positive rates . PartialP<.005. Relationships described in the text were significant at P<.001 unless otherwise mentioned. Depression was causally influenced by self-esteem  and itself  in both cohorts. Anxiety was causally influenced by stress , self-esteem , and itself  in both cohorts. A causal link between anxiety and depression was observed in the first cohort  and only observed in the second cohort with a more liberal threshold . Stress was not causally influenced by any metrics except for itself .Causal influences are shown as directed lines with arrow heads revealing directionality , top, whrp) analysis of contemporaneous relationships revealed significant contemporaneous influences (P<.001) among all four mental health metrics (t) included positive links between anxiety, depression, and stress. Anxiety had positive contemporaneous links to depression  and stress . Self-esteem had negative contemporaneous links to each of the other three mental health metrics, with the strongest negative relationship being stress , followed by depression  and anxiety . Depression had positive contemporaneous links to anxiety (previously mentioned) and stress .The PCMCI partial correlation ( metrics , top. ObP<.005. These results help confirm the vulnerability model and extend previous literature by providing evidence for model testing.Weekly EMAs of self-esteem, depression, stress, and anxiety were collected in two separate cohorts of over 200 college students across an academic year, with an average response rate of 80%. These EMAs were submitted to the PCMCI algorithm, which identified increased stress as a causal factor of future anxiety. Decreased self-esteem was identified as a causal factor of future depression and, to a lesser extent, anxiety. Increased depression was observed as a causal factor for future anxiety, but only in one of the two cohorts at a threshold of This paper and previous research show congruent patterns of correlation among the mental health metrics observed : positivThe most novel and important part of this study is the application of the PCMCI algorithm for the identification of the causal network structure among mental health metrics . PCMCI iThe causal interactions among these mental health metrics can provide evidence to support some current psychological theories. This paper supports the vulnerability model, which suggests that low self-esteem can lead to subsequent depression or anxiety  42,43].,43.42,43The diathesis-stress model has been applied in both depressive and anxious contexts, where pre-existing conditions such as low self-esteem are risk factors, and stressful events can trigger subsequent increases in depression or anxiety in higher risk individuals . There iAlthough the current work provides an analysis of regularly sampled mental health metrics in a college population, a lag of 1 week was selected for simplicity and interpretability. It is possible that other lag intervals may provide additional insight into the causal dynamics of these variables. Given how rapidly mental states can change, weekly resolution may not be the optimal timescale to detect causality between these variables, where more frequent sampling could help further elucidate contemporaneous changes. Moreover, longitudinal sampling over many years may be better suited to testing the scar model . There aThe frequency of sampling needs to be balanced with the burden on study participants, since requesting frequent responses would likely lead to increased participant attrition and may even be an added stressor. As the current study looks to retain individuals over their entire college experience, minimizing the burden on the participant is likely to be a key to retention. Given the goal of long-term participant retention, the total number of questions asked through weekly EMAs was minimized, meaning limited coverage of anxiety or depressive symptoms. Although this may restrict the overarching implications that can be drawn from the current study, the questions were selected based on previous validation and maximal ability to diagnose anxious or depressive symptoms while asking minimal questions ,14. FurtValues of these mental health metrics may change more rapidly than the weekly rate that they are sampled at in this study. Signals associated with fast fluctuations in these metrics would decrease our ability to identify relationships, particularly those that replicate across multiple cohorts, suggesting that the observed results are real and, if anything, underestimate the strength of the relationship between these variables. Increasing the sampling rate to daily or hourly could provide greatly improved insights into the nature of the temporal relationships between these metrics; although, it would increase participant burden and possibly decrease retention. A balance may be provided by using mobile smartphone sensing features to provide some insight into the optimal EMA sampling frequency for future studies. Smart triggering of EMAs, which is based on changes in smartphone features such as motion, conversation, or location, could reduce the total number of times a participant is asked to answer EMA questions while optimizing the temporal resolution and helping to better determine causal relationships among variables. Smartphone sensing features can be sampled hourly or even by the minute with little participant burden except for decreased battery life. Identifying sets of features such as the number of conversations, sleep, or number of locations visited  that preThis study provides a framework for identifying causal factors of anxiety and depression in college students, with the key results replicating in two distinct cohorts sampled weekly over the course of an academic year. Stress is a causal predictor of anxiety, while low self-esteem is a causal predictor of depression and, to a lesser extent, anxiety. These results support the vulnerability model of depression and suggest that ameliorating high rates of stress may reduce subsequent increases in self-reported anxiety. Continually testing and expanding models of the interactions between these and other mental health metrics will be critical to identifying causal factors and potential treatments or strategies to mitigate them, particularly in groups who are at a higher risk than the general population.


Women aged 65 years and older participate in less moderate-vigorous physical activity (PA) than men of this age group, which increases the risk for a myriad of chronic health problems. Interventions that utilize a lifestyle approach to increase PA in everyday life are preferred by women compared to structured exercise, but long-term adherence is a challenge. Technology  can be efficiently leveraged as motivational tools in lifestyle PA interventions. However, the unique needs of older women must be considered. Thus, the purpose is to examine the: (a) types of technology that were successfully integrated into existing PA intervention studies designed for older women; (b) acceptability and adherence to technological approaches by older women; and (c) additional considerations needed for special populations, including older women with chronic health problems. The efficiency and scalability of technological approaches with clinical and public health implications will also be discussed.