Studies of eusocial insects have extensively investigated two components of task allocation: how individuals distribute themselves among different tasks in a colony and how the distribution of labor changes to meet fluctuating task demand. While discrete age- and morphologically-based task allocation systems explain much of the social order in these colonies, the basis for task allocation in non-eusocial organisms and within eusocial castes remains unknown. Building from recent advances in the study of among-individual variation in behavior , we explore a potential mechanism by which individuality in behaviors unrelated to tasks can guide the developmental trajectories that lead to task specialization. We refer to the task-based behavioral syndrome that results from the correlation between the antecedent behavioral tendencies and task participation as a task syndrome. In this review, we present a framework that integrates concepts from a long history of task allocation research in eusocial organisms with recent findings from animal personality research to elucidate how task syndromes and resulting task allocation might manifest in animal groups. By drawing upon an extensive and diverse literature to evaluate the hypothesized framework, this review identifies future areas for study at the intersection of social behavior and animal personality. Consistent individual differences in seemingly task-independent behavioral tendencies can potentially drive task allocation in animal groups. Recent studies have found that animal groups containing behaviorally diverse individuals can outperform less diverse groups. In reviewing the literature, we find support for the hypothesis that efficient task allocation driven by variation among groupmates in task-independent behavior contributes to the success of diverse groups, and we generate predictions for future exploration of this phenomenon. Dictyosteliida (Amoebozoa): Pseudoscorpionida: Lepidoptera: Rodentia: Cetartiodactyla: Carnivora: Passeriformes: Cichliformes: Primates: Task allocation, the process by which groups distribute individuals among tasks to meet variable task demand , may be Animal personality, or the component of behavioral variation in a population that is explained by among-individual variation , has impPresent a conceptual framework connecting social interactions to the reinforcement of among-individual behavioral variation within groups and a group’s adaptive task allocation system;Thoroughly review the evidence evaluating each hypothesized component of the framework;Critically appraise the framework by suggesting circumstances under which it may or may not apply and presenting alternatives to those hypotheses set forth in the framework components;Establish predictions that can guide future tests of the robustness and generalizability of the proposed framework, and suggest a general method for identifying task syndromes.Our conceptual framework  consistsPersonality is the proportion of behavioral variation in a population that is explained by the variation among individuals . BroadlyAccording to these definitions, task specialization, which refers to consistent individual differences in task-related behaviors such as brood care or nest defense, represents personality as well. Thus, an individual can be described by its behavioral type along several axes of variation, some clearly task-related and others that show no explicit connection to task performance. We refer to the latter behaviors as task-independent behaviors, and they are behaviors that: 1) are not explicitly involved in carrying out a task and 2) can be observed and measured when individuals are not participating in a task or are experimentally deprived of the opportunity to participate in a task. At the population-level, any quantifiable association between two axes of behavioral variation, whether they are task-independent or task-related, can be described as a behavioral syndrome . Here, wAmong-individual variation in behavior, or personality, is not mutually exclusive from within-individual variation, or plasticity. Together, these two components define the total variation within a population, and their contribution to the total variation is illustrated well by the behavioral reaction norm approach . An indiImportantly, plasticity can occur at two scales. Activational plasticity reflects the variation in behavior that an individual exhibits across environmental contexts at a given time . SynonymFinally, while personality is defined by the proportion of behavioral variation in a population that is among individuals, when a population comprises social animals, the amount of among-individual variation within a social group can vary among groups. That is, just as groups can differ from each other in their genetic diversity, they can differ in behavioral type diversity. We discuss the feedbacks that can affect the amount of behavioral variation among individuals in social groups, and how this variation affects task allocation and group performance.An individual’s behavioral type is reflected in the food that it eats , the metAlternatively, a behaviorally diverse group that contains individuals with minimal niche overlap could, in theory, result from individuals that have a similar mean behavior, but high within-individual variation in behavior, such that they often exhibit different behaviors and thus fill different ecological niches at any given time. Individuals in this scenario would have higher activational plasticity but similar behavioral types . This alternative, however, is unlikely because there can be substantial costs and limitations to activational plasticity, and predictability can be beneficial in social situations , personality research can contribute to our understanding of the direct role of among-individual variation in task-independent axes of behavior in generating efficient social organization. Given that animal personality is widespread across taxa , we propTo broaden our understanding of task allocation, we employ a modified definition of what constitutes a task. For example, Macaca nemestrina, are important for reducing conflict and maintaining social order , Harris’s hawks (Parabuteo unicinctus), and Aplomado falcons , may partition prey capture tasks and that they may also show consistency in their role across different hunts  which may improve their task performance and generate greater efficiency for the group . “Task pNeolamprologus pulcher, for example, individuals that are more willing to explore a novel environment in an isolated test are more likely to defend a communal territory from an intruding conspecific, while less exploratory individuals are more likely to maintain the breeding shelter  and the process by which groups shift individuals to other tasks as demand changes . In contGroup-level flexibility could potentially be achieved by activational plasticity at the individual level. While specialization implies relative consistency in an individual’s task-related behaviors, task specialists can still show some variation around their mean task behavior. Indeed, even some morphologically specialized eusocial insects are capable of temporarily switching tasks when colony demand changes . IndividAdditional work on eusocial insects has suggested that colonies might further circumvent inflexibility by relying on individuals that are more specialized  for increased productivity and individuals that are less specialized for increased flexibility . Task alGroup-level flexibility in task allocation might also be achieved by developmental plasticity at the individual level. Within-individual variation in task participation discussed thus far in this section represents activational plasticity and does not imply a change in task specialization. Individuals specialize on a given task but show some variation in their task-related behaviors such that they may sometimes perform other tasks. However, it is possible that through developmental plasticity, an individual’s task specialization might actually change over time. This mechanism of flexibility provides a slower and more permanent response to a perturbation in task demands. Honey bees exhibit this developmental plasticity when the population of brood care workers in a colony becomes insufficient, with older honey bees regenerating their hypopharyngeal glands and reverting from foraging back to nursing . The extTask syndromes arise when central tendencies in task-independent behaviors influence developmental trajectories that eventually result in task specialization. The process by which task syndromes develop is, therefore, an example of developmental plasticity. Accordingly, we can conclude that a task syndrome exists when prior task-independent behaviors and current task participation correlate statistically. Empirical tests of the existence of task syndromes will, therefore, require measuring individuals’ antecedent task-independent behavioral type, assessing the tasks in which individuals later participate, and testing for a correlation between them. In practice, this involves taking several longitudinal measurements of relevant behaviors, monitoring subsequent task performance over time, and then modeling task participation as a function of task-independent behavior. But how long should one wait between measuring task-independent behaviors and task performance? Furthermore, developmental plasticity can cause an individual’s reaction norm, and thus their central tendencies in both task-independent and task-related behaviors, to change over time. So, how does one decide when to measure them so as to maximize the chance that they are stable enough to determine the structure of correlation between them?We devote the remainder of this section to putting forth guidelines and benchmarks that will answer these questions in order to aid future empirical tests for the presence of task syndromes. One should ideally measure task-independent behaviors before they might initiate the developmental pathways that result in task specialization and then measure task participation after the developmental change is complete. For animals with relatively discrete life stages  and animals with periodic general behavioral stages , we can infer that developmental change is most likely to happen during the transition between stages. Thus, we might expect task-independent behavioral type in one stage to correlate with task specialization in the next stage . The stage in which to measure task-related behavior and the stage in which to measure task-independent behaviors should be dictated by when individuals most actively partake in tasks. Of course, empirical evaluations will require some system-specific deviations from the scheme established here. For example, with species that hibernate, it might be best to measure task-independent behaviors in one active season and then task participation in the next active season in order to avoid behavioral assays of a hibernating animal.For animals that do not have discrete life stages and do not exhibit periodic behavioral patterns, we suggest measuring task-independent behavioral type when individuals are not fully matured, either sexually or morphologically, and correlating this behavioral type with task specialization when individuals are adults. These potential carryover effects, both between discrete and more continuous life stages, provide a good opportunity to test for task syndromes because task-related behaviors can be more easily isolated from task-independent behaviors due to developmentally or seasonally specific performance of tasks in particular task domains.Despite the presentation of group performance as the culminating response variable of our framework, group performance itself has significant feedback effects on key components of the framework. In the following sections, we incorporate both proximate and ultimate consequences of differential group performance to contemplate not only how task allocation can emerge from sociality, but also how selective pressures on the performance of a group and its members produce more complex social orders.The survival and reproductive success of animals in stable social groups is often critically dependent on the success of their group . The impThe ability of individuals to adaptively change their long-term behavior and central behavioral tendencies based explicitly on metrics of their group’s performance and behavioral composition is highly intriguing but needs much further investigation. It is possible that some animals are not able to accurately track group performance and are, therefore, unable to adaptively shift their behavior. A related issue may be that individuals can and do respond to depressions in group performance but a lack of coordination in behavioral shifts by individuals within the group delays or impedes the establishment of optimal task-independent behavioral type composition. Of course, behavioral types could also be insufficiently flexible, especially as individuals age  or in inChroicocephalus genei, shows that group membership can change in response to poor group performance  similar to their own (Without necessitating a shift in the behavioral reaction norm of individuals over time, a group’s performance could also affect among-individual variation in behavior by impacting group membership. Work with slender-billed gulls, formance . Althougformance . Furtherheir own . WhetherIt will be important for future work to test the hypothesis that an individual’s group choice reflects a preference for avoiding similar behavioral types against opposing hypotheses that explain group membership decisions. Instead of joining a group based on its composition of behavioral types, individuals could be assessing more obvious qualities of individuals in the prospective group such as sex, age, or body size , or evenA group’s performance can impact the amount of task-independent behavioral variation among group members on an evolutionary timescale through three different selective pressures: disruptive selection, negative frequency-dependent social selection, and group selection. Models show that slight differences between groupmates in central behavioral tendencies can result in disruptive selection on behavioral types within the group and selection for increased social responsiveness , which dWolf et al. 2011; In some species, an individual’s fitness is highly dependent upon group dynamics, and group selection can, therefore, maintain an optimal composition of behavioral types within groups . In wateBecause an individual’s task-related behaviors are part of its behavioral type, a group’s performance can impact its task allocation in much the same way it influences the distribution of the task-independent behavioral tendencies in the group. Poor group performance can lead to the reallocation of tasks . Task swImproved group performance as a result of task allocation also influences the evolution of sociality. The evolution of grouping depends critically on the costs and benefits of group-living . Once soAlternatively, it is possible that the occurrence of task syndromes as a result of the framework that we present can actually make a group vulnerable to social parasites. If individuals with certain task-independent behavioral tendencies consistently perform the most relevant tasks for the group, it is possible that behavioral tendencies of other individuals in the group do not predispose them to perform a particular task, or even predispose them to perform no task. This situation might occur with individuals that vary in their general activity level, with the most active individuals performing several tasks and the least active individuals performing no task. The least active individuals in this case will benefit from the tasks performed by their more active groupmates, while providing no benefit to these groupmates. This social parasitism could reduce the benefits of group-living, thus increasing the likelihood of an evolutionary reversal to solitary-living.Despite decades of research into the mechanisms of caste-based task allocation in eusocial insects, studies on mechanisms of task allocation that do not depend on age- or morphologically-based castes remain comparatively scant. In evaluating the literature, we found that among-individual variation in central behavioral tendencies unrelated to tasks could provide a sufficient mechanism for task allocation in species that do not have discrete castes, and that this task allocation might explain the interesting finding that has emerged in several taxa that animal groups containing greater among-individual variation in behavior can be more successful than more homogeneous groups. This extensive review of the literature lends credibility to the field of study at the intersection of social behavior and animal personality.As a critical next step, we suggest future research test the predictions developed herein to evaluate the applicability of the framework to diverse taxa as well as the potential for alternative hypotheses (summarized in We urge empiricists to consider the possibility that some groupmates that seem to be in conflict, may actually occupy complementary roles and exhibit task allocation. For instance, scroungers in groups with a producer-scrounger dichotomy are considered parasites on their producer groupmates. However, both As a final point, this framework has implications beyond behavioral ecology. As Krause et al. predicted in 2010, the rise of animal personality research has drawn interesting parallels to our own species. Studies show that personality diversity in human groups is positively correlated with group performance . Our rev


Rabbits are one of the most used experimental animals for investigating the mechanisms of human cardiovascular disease and lipid metabolism because they are phylogenetically closer to human than rodents (mice and rats). Cholesterol-fed wild-type rabbits were first used to study human atherosclerosis more than 100 years ago and are still playing an important role in cardiovascular research. Furthermore, transgenic rabbits generated by pronuclear microinjection provided another means to investigate many gene functions associated with human disease. Because of the lack of both rabbit embryonic stem cells and the genome information, for a long time, it has been a dream for scientists to obtain knockout rabbits generated by homologous recombination-based genomic manipulation as in mice. This obstacle has greatly hampered using genetically modified rabbits to disclose the molecular mechanisms of many human diseases. The advent of genome editing technologies has dramatically extended the applications of experimental animals including rabbits. In this review, we will update genetically modified rabbits, including transgenic, knock-out, and knock-in rabbits during the past decades regarding their use in cardiovascular research and point out the perspectives in future. Rabbits were first used for disclosing the pathogenesis of human atherosclerosis a century ago. In 1908, a Russian physician, Alexander I. Ignatowski (1875–1955) fed rabbits with a diet supplemented with animal proteins  and found that these rabbits developed pronounced aortic atherosclerosis.Later, a Russian experimental pathologist, Nikolai N. Anichkov (or Anitschkow) (1885–1964) further demonstrated that it was dietary cholesterol rather than proteins that play the critical role in the pathogenesis of atherosclerosis in rabbits and proposed a causal role of cholesterol in the development of atherosclerosis  rabbits was almost concurrently reported by German  cells and the genome information, it has been considered impossible to create KO rabbits by homologous recombination-based genomic modification as to generate KO mice. Unavailability of KO rabbits also constitutes another obstacle that hampers researchers to study loss-of-functions of genes in rabbits. We strived to use somatic cell nuclear transfer technique to generate KO rabbits after Chesne et al. reported the first cloned rabbit about 17 years ago  and was first reported by Brown et al. 50 years ago . FH is an autosomal dominant genetic disorder characterized by elevated plasma LDL levels due to LDL receptor dysfunctions . Since CETP is genetically absent in rodents (mice and rats) and pigs, rabbits are considered the best model for investigation of CETP functions because rabbits have high levels of CETP in the plasma as humans. Taking this advantage, Zhang et al. created CETP KO rabbits and found that CETP KO rabbits showed higher plasma levels of HDL-cholesterol  is a glycoprotein that transfers plasma lipids between HDLs and apoB-containing particles therefore plays an important role in lipoprotein metabolism. However, it is not known whether inhibition of CETP activity can prevent cardiovascular disease because four CETP inhibitors  failed to prove their efficacy in terms of reduction of cardiovascular risk by clinical trials(ApoAII is the second major apolipoproteins in HDLs. However, its physiological functions are largely unknown compared with apoAI. Interestingly, WT rabbits are genetically deficient in apoAII so their HDLs only contain apoAI. This unique feature makes WT rabbits as a “natural” apoAII KO model. We first made Tg rabbits expressing human apoAII gene and found that hepatic expression of human apoAII inhibits cholesterol diet-induced atherosclerosis (Wang et al., Although genetically modified rabbits are an important experimental model in cardiovascular research, they should not be simply used as a substitute of mice and rats, as discussed above. Because rabbits are more expensive, require larger space, and need more time to breed compared with mice, the generation of genetically modified rabbits should be carefully planned to solve those specific problems that cannot be well-examined in other experimental animal models, such as the development of lipid-lowering drugs (Niimi et al., JF, YW, and YC wrote the manuscript. All authors contributed to the article and approved the submitted version.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.


The rapid diversification of synthetic biology tools holds promise in making some classically hard-to-solve environmental problems tractable. Here we review longstanding problems in the Earth and environmental sciences that could be addressed using engineered microbes as micron-scale sensors (biosensors). Biosensors can offer new perspectives on open questions, including understanding microbial behaviors in heterogeneous matrices like soils, sediments, and wastewater systems, tracking cryptic element cycling in the Earth system, and establishing the dynamics of microbe-microbe, microbe-plant, and microbe-material interactions. Before these new tools can reach their potential, however, a suite of biological parts and microbial chassis appropriate for environmental conditions must be developed by the synthetic biology community. This includes diversifying sensing modules to obtain information relevant to environmental questions, creating output signals that allow dynamic reporting from hard-to-image environmental materials, and tuning these sensors so that they reliably function long enough to be useful for environmental studies. Finally, ethical questions related to the use of synthetic biosensors in environmental applications are discussed. Microbes are exquisite miniature sensors, able to sense, integrate, and respond dynamically to a wide range of environmental conditions. Biosensors are genetically-engineered microbes, or stand-alone biological components, that sense and report on specific environmental conditions of interest. Biosensors are an alternative to traditional analytical tools for detecting and measuring environmental signals because they can convert challenging and/or expensive-to-detect signals of interest into easily detectable outputs. They can also report on microbial “experiences” at the micron-scale in complex environmental matrices  a processing module that performs calculations using the input signals, and (3) an output module that produces a detectable and quantifiable signal. Biosensors are depicted using DNA circuit diagrams  environmental scientists and engineers who would benefit from more information on the breadth of current biosensor capabilities, and (2) synthetic biologists who are developing biosensors and would benefit from understanding environmental needs. First, in section A, we discuss challenges in the study of Earth and environmental systems that biosensors are uniquely poised to overcome. We also highlight how synthetic biology can be used to build custom biosensors for use within complex systems to address these hard questions. In sections B and C, we outline the state of synthetic biology and the explosion of biological programs that enable the creation of living and cell-free biosensors. In section D, we highlight needed developments in synthetic biology to advance applications in the Earth and environmental sciences. Finally, in section E, we examine the ethical issues associated with the use of synthetic biology to study the environment.Biosensors create unique opportunities to study ecosystems from the microbial perspective because they are continuously sensing information at the micron scale. In this section, we describe how advanced biosensors offer the opportunity to address outstanding questions of interest to environmental researchers, including the sensing of bioavailable concentrations of chemicals at micron scales, reporting on direct interactions between different organisms, and recording information in cells while preserving the spatial and temporal heterogeneity in the natural environment.Understanding how microbes interact and function collectively is crucial to predicting how communities will respond to future perturbations, since the combined actions of diverse community members drive ecological processes  are expanding the environments where biosensors can be used and the types of environmental processes that can be studied. Biosensors that produce indicator gases instead of traditional fluorescent molecules allow non-invasive measurements of AHL production and degradation rates in soils  can be selectively cultured and quantified  remains limited. To understand how to limit deleterious HGT, such as the spread of antibiotic resistance, it is critical that we develop strategies to monitor the flow of genetic information through microbial communities E. coli was engineered to quantify HGT frequencies by recording DNA fragments acquired from foreign DNA at a single nucleotide level , making the distribution of O2 a critical parameter for understanding how efficiently microbial communities carry out nitrogen cycle transformations. Studies of N2O release at the meter scale in soils have revealed large variations in N2O emissions that span more than an order of magnitude  enzymes responsible for carbon and nitrogen processing, (2) proteins that mediate metal uptake and build the metal cofactors on those enzymes, and (3) bioavailability of metal cofactors  to respond to an environmental condition, and (2) to translate that response into a measurable output  represent a major class of extracellular sensors . TCSs coTCSs are widely distributed across prokaryotes and have evolved to sense a diverse range of environmental conditions  reporters require O2 to fluoresce   and the number of microbial biosensors (a constitutive C2H4 output) performing the sensing  function in both aerobic and anaerobic conditions .2, pH, and lactic acid concentrations . For example, a two-input AND gate  only proCells can be programmed to record their past experiences by converting sensing information into heritable changes. Biological memory is either “permanent” (written into the microbe's DNA in a way that cannot be reversed) or “rewritable” (recorded in a way that enables it to be reset). Memory is appealing for environmental biosensing because it can be read out from both living and dead cells using DNA sequencing or quantitative polymerase chain reaction (qPCR)  into plasmids , which fgain) to be reliably detected. To achieve these performance characteristics, biosensors may require multiple tuning steps and should be rigorously tested in the intended environmental context, i.e., a soil matrix or water sample, for false positive or false negative sensing.To be useful in environmental studies, biosensors must sense and report robustly across complex, dynamic conditions that are less ideal for fast growth as compared to sterile, well-mixed laboratory cultures. Performing well in environmental conditions requires that biosensor inputs are sensitive to the relevant range of environmental conditions and specific enough to only sense the desired condition. Furthermore, biosensors outputs need to report with a high enough signal-to-background  and translation (RBSs) that function in those contexts. Regulatory elements from laboratory strains may not yield the desired activities in non-model organisms because the biomolecules that control transcription (RNA polymerases) and translation (ribosomes) vary across organisms. There are several approaches to build functional genetic circuits in non-model organisms, including (1) the use of native promoters and RBSs that have been characterized in the strain of interest, (2) the implementation of non-native regulatory elements that function independently from native systems, and (3) the use of regulatory elements that present similar functions across a wide range of organisms.Native machinery with a range of activities can be rapidly identified using single-cell transcriptomics . Genes tE. coli  predatory bacteria that live in soils and sediments  have sensing modules that are specific and sensitive to environmental inputs, (2) produce measurable outputs from within environmental samples that are easy to monitor, (3) function robustly over environmental study time scales, (4) use microbial strains of relevance to the processes being studied, and (5) be suitable for safe field applications.2+, Mo3+, Mo4+, Mo5+, Mo6+), osmolytes , signaling molecules , critical materials (rare Earth elements), and environmental parameters . Finally, approaches for tuning input modules' specificity and sensitivity are needed to avoid signal interference from the complex ensemble of chemicals found in environmental samples.There is currently a need to increase the number of sensing modules relevant to studying environmental processes and to expand the application of existing sensors to environmental questions. Biosensors that report on biogeochemical cycle intermediates  could prin situ environmental studies has slowed biosensor applications in complex samples. Common visual reporters are difficult to monitor in situ, due to the high absorbance of light by soils and sediments. Enzymes that produce indicator gases show promise for overcoming some of these barriers (Cheng et al., The paucity of genetically-encoded outputs for E. coli. Significant engineering opportunities exist to develop biological memory that functions across environmental microbes of relevance to diverse Earth and environmental sciences studies.Logic gates and cellular memory have the potential to greatly expand the types of environmental questions that biosensors can address. However, several engineering challenges remain to employing these components in environmental contexts. First, as the number of components in a genetic circuit increases, there is a greater potential for biological noise to propagate through the circuit and destabilize either the ON or OFF states (Pedraza and van Oudenaarden, To function in a complex environmental sample, biosensors need to function on time-scales relevant to the processes under investigation. In some cases, this may require genetic programs that are stable for weeks to months, rather than the hours to days that are typical of most proof-of-concept biosensors. Tuning biosensors for long duration applications will involve methods for keeping the OFF states stable in the absence of inputs. Additionally, tuning will be required so that the ON state reports accurately and consistently across longer time scales following detection of an input. Genetic circuit stability for these longer durations will ultimately depend on the consistent function and stability of each system component, and it will require verification across diverse environmental microbes and samples.High-performance conjugation systems hold promise for programming diverse environmental microbes (Brophy et al., Cell-free sensors hold immediate promise for the safe use of biosensors in the field, and further engineering improvements could broaden their utility. The development of methods for using two component systems in cell-free systems would enable many new environmentally-relevant sensors, given the diversity of chemicals that can be sensed by members of this sensor module family. Environmental samples are chemically complex, and environmental compounds such as organic matter or charged ions have the potential to inactivate cell-free reactions by interfering with biomolecular components (McNerney et al., in situ applications, a range of biocontainment strategies have been developed. These include the creation of auxotrophic strains whose growth depends upon non-natural amino supplementation (Mandell et al., Whole cell biosensors also hold promise for applications in safe settings that prevent release into the environment, such as closed laboratory systems containing soil, sediment, and wastewater that can be autoclaved. To enable National Institute of Health Guidelines for Research Involving Recombinant Or Synthetic Nucleic Acid Molecules recommends a maximum escape frequency of synthetic E. coli corresponding to 10−8 cells (National Institutes of Health, Most of the immediate applications of synthetic biology in environmental sciences involve use of engineered organisms in the laboratory, where the ultimate fate of a biosensor is autoclave death. Laboratory studies with biosensors do not face ethical challenges as long as researchers adhere to modern microbiology laboratory standards. However, it is likely that researchers will eventually attempt to use synthetic microbes as detectors outside the laboratory and this raises a host of questions about risks associated with either accidental or intentional release of engineered organisms into the wild. The E. coli, the assumption has been that cell fitness will be low in such settings. However, when programming microbes native to an environmental niche, this may not be the case. These considerations should occur throughout the experimental timeline, and designs that violate either laws or ethical norms should not be developed under any circumstances. Because members of research groups planning an environmental release are unlikely to be unbiased in their evaluation, groups should engage scholars from outside their team with expertise in ethics of genetically modified organisms.The misuse or poorly-planned use of synthetic organisms in the environment has the potential to damage the natural world. Every research project involving environmental synthetic organisms should include explicit consideration of ethics, with the extent of resources invested in ethical considerations increasing with the potential for environmental release. For example, experiments that use large populations of microbes that have a greater potential for release and environmental damage should be considering the local setting where release could occur and the implications of that environmental material for synthetic cell fitness. With laboratories strains of IDV, EF, PK, JS, CM, and LS conceptualized and wrote the manuscript, while IDV and EF synthesized the figures and table. All authors contributed to the article and approved the submitted version.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.


Previous studies have shown that making future care planning often involves several steps. This is consistent with the transtheoretical model of behavior change which identified stages in which behavior changes over time and progresses through a series of six stages . Although most studies on future care planning among older adults have examined the progression from the pre-contemplation stage to an action stage, little is known about the unique characteristics of older adults at the contemplation stage. Our sample included 409 randomly selected older adults in Cleveland, Ohio who were in the first wave of a longitudinal study of successful aging . We used multivariate logistic regression to predict older adults who are more likely to have thought of their future care plans (contemplation stage). Results indicate several individual and relationship factors such as marital status, engaging in health behaviors (not smoking), being young old, and having personal transportation  account for contemplating future care. These findings underscore that several individual resources, as well as relationship status, are associated with contemplation stage of future care planning. The results reinforce the idea that future care planning is a stage-based behavior that people engage in, rather than a stand-alone activity.


Quiescence is a cellular state in which a cell remains out of the cell cycle but retains the capacity to divide. The unique ability of adult stem cells to maintain quiescence is crucial for life-long tissue homeostasis and regenerative capacity. Quiescence has long been viewed as an inactive state but recent studies have shown that it is in fact an actively regulated process and that adult stem cells are highly reactive to extrinsic stimuli. This has fuelled hopes of boosting the reactivation potential of adult stem cells to improve tissue function during ageing. In this Review, we provide a perspective of the quiescent state and discuss how quiescent adult stem cells transition into the cell cycle. We also discuss current challenges in the field, highlighting recent technical advances that could help overcome some of these challenges. Summary: This Review provides a perspective of the quiescent state of adult stem cells and discusses how recent technical advances could help overcome some of the challenges in the field. Tissue-specific stem cells, also known as adult stem cells, reside in somatic adult tissues, where they contribute to tissue homeostasis and repair . Unlike Quiescent adult stem cells resist environmental or radiation-induced stress and can regenerate their whole lineage after an insult . SimilarAdult stem cells in different tissues use various strategies to ensure their maintenance over the lifespan of the organism . One sucAlthough quiescence has long been considered an inactive state, recent studies have shown that it is actively regulated and modulated by both cell intrinsic and extrinsic signals. Moreover, thanks to technical advances, some studies are beginning to shed light on how quiescent adult stem cells become activated at the molecular level. These include studies of quiescent HSCs, neural stem cells (NSCs) and muscle stem cells (MuSCs), to name a few. In this Review, we highlight some of the general principles governing the maintenance of adult stem cell quiescence and the transition of adult stem cells from the quiescent to the active state. We focus on the main challenges in studying stem cell quiescence and provide an overview of how techniques such as single-cell transcriptomics, proteomic profiling and intravital imaging are advancing our understanding of the quiescent cell state. For a more thorough review of stem cell quiescence in different tissues as well as the mechanisms controlling quiescence, we refer readers to excellent recent reviews .An overarching characteristic of all quiescent adult stem cells is that they exist in a reversible G0 cell cycle state. This distinguishes them from differentiated and senescent cells, which exist in an irreversible G0 cell cycle state . Quiescein situ with or without injury stimulation -HSCs or dormant HSCs have the most significant regenerative potential but they are in a deep state of quiescence and divide only about five times during the lifetime of a mouse . LT-HSCsmulation . Indeed,mulation . As we dQuiescence is also usually associated with an inactive cellular state. For example, cellular quiescence is characterized by a lack of expression of cell cycle-related genes and a global downregulation of mRNA production and protein synthesis, as observed in plants, yeast or even some proliferative mammalian cells, such as fibroblasts that become quiescent in response to serum starvation or contact inhibition. However, the quiescent state of adult stem cells is not just an inactive phase but is actively regulated . QuiesceAdult stem cells are actively regulated, both as they transition into and out of quiescence, and while they are maintained within the quiescent state . A combiin vitro systems can be translated into adult stem cell biology. Global levels of activated cyclin-dependent kinases (CDKs) are the primary driver of cell cycle progression. CDK activity is determined by the balance of CDKs, cyclins and CDK inhibitors present within the cell, and is regulated by extrinsic mitogenic signals  enter quiescence while in G2 , it is no longer necessary to sort or identify cells prior to sequencing, and bioinformatic tools now allow the identification of cell types from whole-tissue sequencing . AlthougIn the past few years, scRNA-seq studies have clearly shown that the stem cell state is not distinct but rather a continuous transition from one state to another. This applies to the transition of a stem cell to more differentiated progeny and also to the transition from deep quiescence to active states . These sIn many cases, scRNA-seq has revealed unexpected heterogeneity in populations of adult stem cells that were previously thought to be homogeneous. The intestinal epithelium is a high turnover tissue maintained by highly proliferative Lgr5-positive intestinal stem cells. However, scRNA-seq studies have identified a new, slowly cycling sub-population of Lgr5-positive stem cells characterized by the expression of the RNA binding protein Mex3a . These MEpigenetic mechanisms are tightly linked to ageing and metabolism, and play an essential role in adult stem cell maintenance . As suchHowever, epigenetic modifications remain challenging to study in quiescent adult stem cells, mostly owing to difficulties in obtaining enough material to perform the necessary molecular assays. Significant advances have been made in recent years to minimize the cell input required for techniques such as ChIP-seq , Hi-C L and ATACMany of the crucial activation factors for adult stem cells, such as MyoD1 for MuSCs or Ascl1 for NSCs , are alsRecent advances in transcriptomics, although remarkable, are not enough to provide a complete picture of the quiescent state and its regulation. This is because critical modulators are often highly unstable proteins that show poor correlation between protein and mRNA levels . Post-trWhile advances in single-cell proteomics have been – and continue to be – made, the application of these techniques to study stem cell quiescence is in its infancy. Single cell mass cytometry time of flight (CyTOF) is an approach used to capture the temporal dynamics of transcription factor (TF) expression in individual cells . This tein vitro (Niche signals are crucial for stem cell quiescence. Therefore, it is not surprising that tissue dissociation is sufficient to activate adult stem cells. Indeed, MuSCs dramatically change their expression profile due to the dissociation protocol alone . This rain vitro . Therefoin situ as soon as possible after dissection to preserve their in vivo signatures. The use of RNA synthesis inhibitors during the isolation of MuSCs also prevents changes in transcription that are induced by the removal of stem cells from their niche (ex vivo immediately after tissue isolation or systemically through perfusion of fixatives can also help capture the authentic quiescent signature of adult stem cells (in situ molecular signatures, it will be possible to examine the profile of stem cells at defined times after activation, for example during the early windows of stem cell activation that are currently missed during conventional isolation processes. This will potentially unearth the molecular mechanisms that are crucial for exit from quiescence and early activation. Other strategies initially developed to improve RNA-sequencing quality could also help preserve quiescent cell gene expression. For example, freezing fresh tissue followed by the sequencing of single-cell nuclei has been shown to preserve RNA integrity and improve sequencing data quality (One such approach involves fixing stem cells ir niche . Fixatioem cells . One of em cells . Interes quality .in vivo is high throughput in situ hybridization (Another technique with great potential to help unravel the real quiescent signature dization . This apin situ expression data for stem cells and their niche. This is particularly evident when trying to understand direct cell-cell interactions or lineage dynamics. In the case of lineage-tracing experiments, reconstructed lineages are usually inferred from a few time points after labelling, which rarely reflect the actual dynamics of stem cell divisions. Imaging-based approaches, such as intra-vital imaging, therefore have the potential to uncover unique features of quiescent and activated adult stem cells, and their interaction with the niche.Certain aspects of stem cell behaviour, such as stem cell dynamics, remain hard to study even with high quality A characteristic feature of quiescent adult stem cells arising from live-imaging studies in different tissues is that they have minimal mobility, strengthening the importance of their close association to niche components . The visIntra-vital imaging has also revealed the mode of division of adult stem cells, often giving a much more complex picture than previously thought. This is the case in the adult hippocampus, where adult NSCs were shown to divide in a wide array of modes . These iIntra-vital imaging can be a very powerful tool for the study of adult stem cells when combined with genetic tools to disturb their properties. In the hair follicle, for example, single cell tracking and manipulation of stem cells in live mice revealed unexpected flexibility of lineage choice not only after injury but also under homeostatic conditions . The usein vivo, together with the intrinsic scarcity of quiescent adult stem cells. For example, it is still unclear how adult stem cells integrate the signals they receive from the niche to mount an appropriate regenerative/homeostatic response. Some progress has been made identifying crosstalk between the pathways controlling quiescence. An example of this is the dampening of the Akt pathway by ERK signalling that occurs in activated HSCs, allowing them to return to quiescence (in situ imaging and the development of sensitive reporter lines for pathway activation, will undoubtedly help us further unravel such signal integration mechanisms. The potential asymmetric distribution of molecules and cellular compartments between daughter cells is also gaining attention as another determinant for the re-entry into quiescence after division. In addition to the well-known differential distribution of cell cycle determinants, some adult stem cells can differentially segregate damaged proteins between daughter cells. This phenomenon relies on a diffusion barrier in the endoplasmic reticulum at the time of mitosis and has been proposed to preserve the fitness of the cell retaining stem cell properties (Rapidly developing technologies are contributing to our understanding of the quiescent state at unprecedented speed. However, there are still important aspects of quiescence that remain obscure, mostly owing to the lack of proper tools to investigate them iescence . Advanceoperties . The difAs discussed above, quiescent adult stem cells undergo dramatic changes as they enter the cell cycle. Activation is associated with increases in RNA and protein content, relaxation of heterochromatin and extensive changes in metabolism that require a significant reorganization of biological molecules within cellular compartments and organelles . ProfounThe process of phase separation, which is involved in the formation of membrane-less organelles , is alsoThe modulation of adult stem cell quiescence holds great potential to increase tissue repair, both after injury and during normal ageing. Interventions aimed at improving the activation of quiescent adult stem cells have already been proposed as a rejuvenation strategy in some tissues. However, before we can safely apply these interventions, we must investigate the long-term consequences of altering quiescent adult stem cell populations. It will be crucial to determine, on a tissue-by-tissue basis, whether stem cell activation leads to loss of the stem cell population and, therefore, to a further loss of tissue function at later time points. To prevent this, any interventions increasing stem cell activation should be accompanied by the promotion of regulated self-renewal to ensure the long-term maintenance of stem cells and their regenerative potential. Further studies that aim to better understand the quiescent state and how it is regulated will therefore undoubtedly aid the development and application of regenerative and rejuvenating strategies.


The COVID-19 pandemic has exposed the fragility of our food systems. Despite increased efficiencies in producing and supplying large volumes of food, our current food systems have generated multiple adverse outcomes comprising high greenhouse gas emissions, persistent hunger, and livelihood stress for farmers around the world. Nowhere else than in Africa have large numbers of people experienced more acutely these adverse shocks emanating from our food systems. Thus, building more resilient African food systems, which take a radical change of direction, is fundamentally a matter of survival. While there is broad consensus around a need for transformational change in food systems, what that entails is not always clear, and there are divergent views amongst experts on how to re-orient research priorities and agricultural solutions in ways that effectively address hunger and inequality while also protecting agrobiodiversity and the environment more broadly. This article engages with this debate and proposes an agricultural research for development agenda in Africa that balances technology transfer with realigning societal values, institutional arrangements, and policy decision-making towards the realization of greater sustainability and inclusive outcomes. In major African cities such as Nairobi, Kinshasa and Lagos where up to two-thirds of the population rely on the informal sector for their livelihoods, millions of people have been left without income to purchase food due to the abrupt loss of jobs that often provide daily earnings. In rural areas where agriculture is the main source of people’s livelihoods, disruptions to transportation and logistics have made it difficult for producers  to sell their produce and to gain access to agro-veterinary inputs and services.Various actors point to threats of a looming global food crisis2 while others scramble to find alternative markets. The effects of these restrictions might result in higher food prices, akin to experiences from the Ebola crisis in West Africa in 2014, which disrupted agricultural supply chains. Today, the COVID-19 pandemic puts a further strain on Africa’s agricultural sector which is already facing unfavorable climate change patterns involving a higher frequency and intensity of extreme weather events such as droughts and floods, market and price volatility, and the recent desert locust outbreak in the Horn of Africa.In Kenya, for instance, a country-wide curfew (7 PM-5 AM) and movement ban in and out of four counties, including Nairobi, have seen smallholder farmers who produce over 70% of the food consumed in the country face high transportation fees to deliver their produce to citiesTo address the immediate food security shocks brought about by the COVID-19 pandemic, multiple African governments have introduced relief measures to cushion the poorest and most vulnerable segments of their populations as well as to ensure that producers have affordable access to farm inputs.3. The COVID-19 outbreak has brought to the fore some of the existing challenges facing our food systems. For example, while current food systems have become efficient at producing and supplying large volumes of food, they have generated multiple adverse outcomes comprising high greenhouse gas emissions, persistent hunger, and livelihood stress for farmers around the world4.Beyond tackling the immediate concerns surrounding health and food emergencies, global food security leaders reiterate that the COVID-19 crisis offers an opportunity for decisive collective action towards building resilient food systems that enhance ecological sustainability and equitable outcomes5.Nowhere else than in Africa have large numbers of people experienced more acutely these adverse shocks emanating from our food systems. Thus, building more resilient African food systems, which take a radical change of direction, is fundamentally a matter of survival. African Ministers of Agriculture, speaking on the impact of COVID-19 on food security and nutrition in Africa, have emphasized that developing sustainable and resilient food systems in Africa can address various negative influences beyond providing adequate food, including on public health, youth employment, education, economic development and social well-being6 in ways that effectively address hunger and inequality while also protecting agrobiodiversity and the environment more broadly.While there is broad consensus around a need for transformational change in food systems, what that entails is not always clear, and there are divergent views amongst experts on how to re-orient research priorities and agricultural solutions7. For other actors, resilient food systems promote diversified agroecological farming and landscapes, based on the principles of food sovereignty, and are intended to produce diversified outputs ranging from increased dietary diversity from locally produced food, minimal shocks from crop and market failures, and autonomy over how resources are used8. Further, it brings greater scrutiny and critical debate to normative assumptions surrounding food security as well as to the political capital and priorities that lock-in place current unsatisfactory practices in food systems9.For some actors, resilient food systems are productive and efficient, and operate under the principles of climate-smart agriculture and sustainable intensification. Ideal food systems are also envisioned to support the inclusive participation and economic empowerment of especially marginalized food producers and agricultural workers such as through favorable integration into food value chains10.Both of these food systems resilience paradigms offer a wide diversity of proven agricultural technologies, practices and valuable insights that can enhance the resilience of Africa’s producers and food systems. However, agricultural technology uptake amongst producers has often proved challenging and many commendable innovations fail to expand their reach to large numbers of beneficiaries in a manner that is self-sustaining or long-lasting. There are multiple reasons for their limited impact at scale. Among them is that most efforts tend to narrowly focus on generating more produce or income from existing farms but pay relatively scarce attention to the different dimensions of agricultural systems constrains , or whether innovations necessarily align with the specific constraints, interests and motivations of smallholder producers and other stakeholders11. This process will need to pay attention to and support the following elements:Offer low-cost or cost-effective agricultural innovations and practices that can enhance the resilience of Africa’s resource-constrained producers to hedge safely against risks in environments where they are routinely subject to multiple unpredictable shocks and outcomes .Build the agency of individuals and communities to foster ownership in the management and control of such agricultural innovations, as well as to advocate for their own priorities and interests more effectively, beyond the short-term duration of typical agricultural development interventions.Engage with decision-makers to advocate for the implementation of strong institutional or policy mechanisms that support context-appropriate agricultural solutions and can enhance resilience in Africa’s food systems.Support research and learning that informs African food producers and consumers about the value of strengthening food systems resilience in a manner that provides nutritious and healthy food while delivering livelihood benefits to farmers and promoting sustainable agricultural practices.Building more resilient food systems in Africa will require reconfigurations that balance technology transfer with realigning societal values, institutional arrangements, and policy decision-making towards the realization of greater sustainability and inclusive outcomesWhen taken together, these elements can help to reposition agricultural interventions to enhance food systems resilience impact in Africa. Various actors and initiatives are already working towards this agenda. However, their efforts often face enormous structural constrains and struggle to gain the necessary political and financial support needed to meaningfully expand their impact at scale.12. This work aims to lend greater to farmers’ social seed networks, commonly referred to as informal seed systems, which in most parts of Africa supply up to 80% of the seeds grown by smallholder farmers. These community seed banks serve multiple key functions. Among them isin-situ conservation of local plant genetic resources, and access to greater varietal diversity of seeds and planting materials acquired from national and regional gene banks and farmer-to-farmer exchanges. Despite this vital role that informal seed systems play in the production and distribution of a vast majority of the seeds used by Africa’s smallholder farmers, they are often overlooked in dominant seed system development endeavors which largely favor the expansion and commercialization of formal seed systems13.For example, Bioversity International and the CGIAR Research Program on Climate Change, Agriculture and Food Security (CCAFS) have supported the establishment and capacity-enhancement of community seed banks in Uganda, Kenya and Uganda14. For AFSA, agroecology should focus on building upon Africa’s diverse food systems and traditional farming practices, while ensuring that farmers are in control of all aspects of food production. While AFSA has seen increased recognition in some global policy arenas, the movement faces difficulty accessing critical national and regional policy spaces that can facilitate the implementation of some of its agroecology efforts15. To them, African agricultural policymaking is biased towards intensifying the production of staple crops, using a narrow range of agrochemicals and improved seeds as evident in multiple Farmer Input Subsidy Programmes16.Similarly, the Alliance for Food Sovereignty in Africa (AFSA), one of Africa’s biggest civil society movements, is involved in an advocacy campaign for agroecology across Africa. Agroecology seeks to (re)design farming systems in ways that maximize agrobiodiversity using a wide range of crops, seed varieties, and farm animals, as part of a strategy to stabilize food supply against climatic variability and seasonal shortages, while building healthy agro-ecosystemsAs Africa’s policy-makers grapple with how to meet the food security demands of their nations considering disruptions caused by the COVID-19 pandemic, now is also a time to consider system-wide reconfigurations that can build greater resilience in local and national food systems. Evidence from Africa-based organizations and movements demonstrate that investing in approaches that build the agency of producers and their communities to improve their agricultural practices can guarantee the stable supply of healthy and nutritious food. These efforts can help feed Africa adequately and sustainably, but they will need much greater political and financial support.No data are associated with this article. Overall, this article raises concerns over a looming food crisis in the Sub-Saharan Africa (SSA) region as a result of the global COVID-19 pandemic. The author argues that increasing food insecurity in both urban and rural populations is resulting from declining food production, reduction in transportation services and a loss of thousands of jobs, largely in the informal labour sector.The author argues for a radical shift in policy and research direction for addressing these pressing challenges and suggests building more resilient food systems that overcome underlying bottlenecks such as: improving public health services, access to education and youth unemployment. The author describes varying approaches to building resilient food systems, through food sovereignty, agro-ecology and through improved productivity and efficiency but argues that these approaches often result in narrowed outcomes that are focused on economic gains.  The author makes a number of recommendations for building more resilient food systems that could withstand future shocks and uncertainties, and that could mitigate the long-term impact of the current global pandemic. The article makes a strong case for shifting attention from technologically-focused innovations to cost-effective, demand driven strategies that consider individuals' and communities' agency, their control and ownership over innovations and an overall more holistic approach to multi-level decision making, learning and education.The author suggests that a radical or transformational change is necessary for future resilient food systems across the SSA region. The analysis could pay further attention to how substantive structural changes are needed. For example, analysis of financial and political actors that support current and future scalable and technologically-driven initiatives could identify specific investment needs around integrating resilience strategies into food systems.Considerations for the politics of knowledge and power relations behind agenda-setting and policy formations are also necessary to ensure that strategies are designed to meet the long-term, sustainable needs of both rural and urban dwellers in SSA. An emphasis on the processes involved in building resilient food systems could highlight approaches that include those affected the most,  in collaborative, co-design planning, research and implementation.Shocks brought on by the pandemic also pose specific risks to different actors within food value chains. Informal food vendors, material suppliers, factory workers (in food processing) for example, are all vulnerable to contracting the virus but who also risk losing their livelihoods without continuing their work in some capacity. Social protection measures are a necessary factor in establishing future food systems that benefit everyone. Further to this, context-specific, intersectional considerations  in the analysis could further the discussion around social and economic inequalities within food systems, and the exacerbating impact of the pandemic on the most marginalized populations.Does the article adequately reference differing views and opinions?YesAre all factual statements correct, and are statements and arguments made adequately supported by citations?YesIs the Open Letter written in accessible language?YesWhere applicable, are recommendations and next steps explained clearly for others to follow?YesIs the rationale for the Open Letter provided in sufficient detail?YesReviewer Expertise:Social Anthropology of nutrition and agricultural development and gender.I confirm that I have read this submission and believe that I have an appropriate level of expertise to confirm that it is of an acceptable scientific standard. This is a timely and well-argued piece on a very important set of issues. Only a few minor revisions are needed, in my view. The following points are offered in the spirit of constructive criticism:Money Flows: What Is Holding Back Investment In Agroecological Research For Africa? argues that “As many as 85% of projects funded by the BMGF [Bill and Melinda Gates Foundation] and more than 70% of projects carried out by Kenyan research institutes were limited to supporting industrial agriculture and/or increasing its efficiency via targeted approaches such as improved pesticide practices, livestock vaccines or reductions in post-harvest losses”, rather than more agroecological practices which might address the issues mentioned in this article. A little more critical attention to the political economy of agricultural research – mentioning perhaps the “Green Revolution for Africa” paradigm – would better align the article with its important recommendation that stakeholders “Build the agency of individuals and communities to foster ownership in the management and control of such agricultural innovations”. The article talks of “agricultural technology uptake” and “limited impact at scale”, providing some reasons why this is the case. However, it doesn’t emphasize the overall political economy of corporate and 'donor' involvement in African food systems. To some extent it covers this in the penultimate paragraph: “African agricultural policymaking is biased towards intensifying the production of staple crops, using a narrow range of agrochemicals and improved seeds as evident in multiple Farmer Input Subsidy Programmes”. Nevertheless, perhaps a few sentences on the involvement by agribusiness multinational companies  and philanthropic-public-private partnerships would make for a more critical analysis. Sources such as IPES-Food (2020) Personally, I would argue for a few sentences at least on the broader agrarian issues involved – based on a brief discussion of (gendered) labour, capital  and land. Issues around women’s access to land especially, and land acquisition by large-scale corporations, might deserve attention. The following are more minor issues: The Abstract talks of the “fragility of our food systems”. While the reader might assume “our” means “African”, it could also be taken to mean “global”. The author should specify.https://www.oxfam.org/en/press-releases/12000-people-day-could-die-covid-19-linked-hunger-end-year-potentially-more-disease The first sentence of the introduction mentions “Various actors” but only includes 1 reference. Another recent reference would be Oxfam’s report ‘The hunger virus: how COVID-19 is fuelling hunger in a hungry world’ “while current food systems have become efficient at producing and supplying large volumes of food, they have generated multiple adverse outcomes comprising high greenhouse gas emissions, persistent hunger, and livelihood stress for farmers around the world”. To give a broad sense of negative impacts, the author might consider mentioning other environmental impacts . “it brings greater scrutiny and critical debate to normative assumptions” – what does the “it” in this sentence refer to? Scholarly and policy debates? The concept of resilience? The increased scrutiny of our food system due to covid-19 impacts? “Among them is that most efforts tend to narrowly focus on generating more produce or income from existing farms but pay relatively scarce attention to the different dimensions of agricultural systems constrains” – misspelling of the last word. There is another misspelling (“constrains”) later in the article.Does the article adequately reference differing views and opinions?YesAre all factual statements correct, and are statements and arguments made adequately supported by citations?YesIs the Open Letter written in accessible language?YesWhere applicable, are recommendations and next steps explained clearly for others to follow?YesIs the rationale for the Open Letter provided in sufficient detail?YesReviewer Expertise:Food security; political economy of natural resources management in East Africa; land reforms in East and Central AfricaI confirm that I have read this submission and believe that I have an appropriate level of expertise to confirm that it is of an acceptable scientific standard.


The objective of this study was to develop a measurement tool to capture local public health department (LHD) organizational characteristics that align with implementation of equity-oriented practice, which may be used to gauge progress in building public health structures and functions that address the needs of vulnerable populations and reduce health inequities.We developed and tested a measurement tool, with practitioner input, based on an implementation science framework and informed by previous work defining public health essential services and practice recommendations for health equity. Measures assessed types of vulnerable populations served by the LHD, organizational climate, and four equity-oriented practice areas, including: assessment and planning, monitoring and analysis, leadership support, and obesity prevention. We also assessed opportunities for capacity building by identifying training needs of practitioners. Primary data were collected from Missouri local health department practitioners  via an online questionnaire, with a subset of the sample providing data for test-retest reliability.Measures of equity-oriented implementation climate indicated areas of variability with respect to strengths and gaps across LHDs. While implementation climate was strong with respect to perceived importance (86%), a substantial proportion of LHDs cited concern over other priorities conflicting with equity-oriented implementation (32%). Likewise, a strong internal push (67%) was often accompanied by limited external political (25%) and community support (40%). Implementation climate measures generally had good to excellent reliability and were significantly associated with areas of equity-oriented practice. Frequently identified (>70%) training needs included improving skills in applying frameworks, assessment methods, and evaluating collaborations around equity.We developed a theory-based, practitioner-informed questionnaire to assess capacity for equity-oriented practice and identify opportunities for capacity building in local public health departments to engage in effective change toward health equity. The inequitable distribution of social, economic and structural determinants of health and system-wide gaps in addressing the health needs of vulnerable populations have led to stark disparities in morbidity and mortality –6. In orCurrent efforts to set standards of practice across the US public health system may help align local public health practice with efforts to better address social determinants of health inequities. For example, the national public health accreditation program prescribes a number of standards and measures that address health equity . HealthyRecent work in implementation science offers a theoretical basis for understanding elements of organizational capacity for innovation, providing an important synthesis of models and key domains for identifying implementation-related constructs that can be translated into measurable standards of equity-oriented practice. The consolidated framework for implementation science (CFIR) is a widely used meta-framework that organizes numerous constructs across domains representing multiple levels both internal and external to the organizational environment . FurtherIn theory, organizational climate and capacity are particularly appropriate to examine in the context of health equity-oriented practice because of the importance of engaging in multifaceted, strategic approaches , 15, theA link to an online questionnaire  was sent via email to all 115 LHD top administrators in Missouri. In addition to the original survey invitation, non-respondents received up two to three email reminders and a phone call. Responses were received from 92 participants for a final response rate of 80%). The survey was open from January 2016 to April 2016.Approximately two weeks after the baseline questionnaire was completed, 52 selected administrators (based on willingness to participate as indicated in baseline survey) were sent a request to complete the questionnaire a second time as part of the test-retest study. Non-respondents received one email reminder. Responses were received from 28 participants for a response rate of 54%. The study protocol was approved by the Saint Louis University Institutional Review Board.The questionnaire was developed based on theoretical frameworks and prior health equity initiatives in LHD settings using newly created and adaptations of existing items. The Consolidated Framework for Implementation Research (CFIR) provided an overarching framework for identifying relevant implementation domains both outside and within the LHD organizational setting . One speThe final questionnaire integrated implementation climate domains with previously developed measurement items characterizing aspects of LHD infrastructure and essential functions, adapted to the aims of the current project , 20. We Once the questionnaire was drafted, it was reviewed by three former LHD administrators to ensure construct validity of measurement items and to provide feedback on acceptability and feasibility of conducting the survey among the intended sample of current LHD administrators. Suggestions were provided for modifying wording to clarify individual questions, dropping questions to lessen the time burden involved with participating in the survey, and wording for the introductory email to request participation, with the questionnaire and data collection methods revised accordingly. The final questionnaire included measurement items representing four domains of implementation climate (16 items), and four practice areas: assessment and planning (9 items), monitoring and analysis (8 items), leadership support (11 items) and obesity prevention practice (7 items). The questionnaire is available in its entirety as a Response scores from individual measurement items were summarized to create scales representing four separate domains of implementation climate, an overall implementation climate scale, and the four action areas , with higher scores indicating more engagement. The resulting data were examined with descriptive statistics . Linear regression models were used to examine whether higher implementation climate score was related to higher scores in the four action areas. Test-retest reliability was assessed by calculating intraclass correlation coefficients using the formula for 2-way, mixed effects . Test-reWhen asked to identify the specific vulnerable populations in their jurisdictions, 100% of LHD respondents identified low income groups, followed in frequency by low education, elderly, and children/infants . ParticiEquity-oriented implementation climate was organized in four sub-domains: relative priority, tension for change, compatibility, and organizational incentives and rewards . In termTest-retest reliability results for the newly-developed implementation climate items indicated that most items had at least moderate to good reliability, with individual item ICC values ≥0.5 for thirteen and ≥0.7 for five of sixteen items. In addition, ICC for the four subdomains ranged from 0.55 to 0.85, and for the overall implementation climate score was 0.82.Results from regression models examining the relationship between implementation climate and engagement in the four equity-oriented action areas are reported in Local public health departments are essential to the implementation of health equity initiatives, in large part, because they are poised to provide the needed contextualization in order to adapt practices to the vulnerable populations in their jurisdiction in collaboration with community members and other key partners across sectors. However, measurement tools are needed in order to assess capacity and identify specific organizational supports that bolster these health equity-oriented practices. The current study contributes to our understanding of structures and processes that may be identified as leverage points for implementation strategies designed to improve equity-oriented approaches in local public health departments .Our findings further show that in LHDs where implementation climate is more supportive of health equity there is a higher likelihood of engagement in assessment, planning, and monitoring of activities specifically geared toward health equity in general and specifically with regard to obesity initiatives. LHDs in Missouri generally agreed with the importance of promoting the health of vulnerable populations and see a strong fit with organizational values and norms. However, there were frequently cited concerns about health equity initiatives conflicting with other organizational priorities, and the lack of external political and community support for this work. This may bode poorly for sustainability, if efforts to promote equity are seen as competing with other priorities rather than as being integrated with overall organizational strategy. Current national efforts, such as the national public health accreditation program, whose standards and measures include a number of items related to health equity may help to overcome some of this lack of local support and act as an external push toward more LHD equity-oriented implementation .LHDs also highlighted the importance of a number of areas for future training. For example, cross-sector collaboration and recognition of gaps in capacity in this area was exemplified by the majority (74%) of respondents expressing the need to improve their ability to evaluate these collaborations. These findings point to the importance of training health department personnel so they have a better capacity for collaborative initiatives and enhanced understanding of health equity and social determinants as well as how they can translate these lessons to those outside the health arena in ways that enhance support rather than create opposition. The high frequency of respondents that indicated they wanted additional training and skills in the area of assessment and evaluation suggest this is another area for future training.This is the first study that we are aware of that has developed a theory-based measure of implementation climate and examined it in relation to other areas of equity-oriented practice in local public health departments. Local health department organizational characteristics, including leadership engagement, and training needs, have been previously found to influence prioritization of strategies based in evidence, which may be more broadly construed to include equity-oriented practice . Prior wOur tool provides a way to take a snapshot in public health settings across a broad range of local communities. It does not, however provide a comprehensive organizational assessment, such as the tool created by the Bay Area Regional Health Inequities Initiative (BARHII) . As suchThe study was conducted only in Missouri. In many ways, the findings could be more broadly applicable. The distribution of Missouri county LHD jurisdictions in the study sample is similar to that of US counties with respect to population size, with a slightly higher proportion of small-sized counties in the Missouri sample . Within Missouri it was important to recognize that there are different vulnerable populations within LHD jurisdictions, and that this might influence LHD actions. It is noteworthy that the vulnerable populations that were identified most frequently by LHDs were low income, low education, the elderly and children. Future work might explore if this is due to LHDs responding with respect to objective assessment of community needs, or if other factors impact LHD capacity to recognize and address the needs across a broader set of vulnerable population groups. In addition, it is unclear if the tool might have different utility for LHDs that define the vulnerable populations in their jurisdiction that are most in need of prevention and public health services as being racial/ethnic minorities. Future studies might examine the utility of the tool for LHDs where racial equity might be the most appropriate lens. Further work could also aim to expand the size and geographic range of the sample and examine additional psychometric properties of the newly-developed measures in order to improve understanding and increase generalizability across contexts.In many ways public health as a field has valued the ability to understand the nature of relationships among variables over the ability to learn with communities how best to intervene to affect change  In orderS1 Appendix(DOCX)Click here for additional data file.S1 Data(XLSX)Click here for additional data file.S2 Data(XLSX)Click here for additional data file.S3 Data(DOCX)Click here for additional data file.S1 Questionnaire(DOCX)Click here for additional data file.


Cutaneous nociception is essential to prevent individuals from sustaining injuries. According to the conventional point of view, the responses to noxious stimuli are thought to be exclusively initiated by sensory neurons, whose activity would be at most modulated by keratinocytes. However recent studies have demonstrated that epidermal keratinocytes can also act as primary nociceptive transducers as a supplement to sensory neurons. To enlighten our understanding of cutaneous nociception, this review highlights recent and relevant findings on the cellular and molecular elements that underlie the contribution of epidermal keratinocytes as nociceptive modulators and noxious sensors, both under healthy and pathological conditions. The skin forms a protective and sensory interface between our body and the external environment. Its outermost layer, the epidermis, consists in a stratified squamous epithelium mainly composed of keratinocytes that proliferate from a basal layer over the basement membrane and then differentiate and migrate to the surface in a coordinated way to successively define the spinous and granular layers topped by the stratum corneum.The dogma underlying somatosensation indicates that keratinocytes account solely for physical and chemical barrier, whereas sensory neurons, via their extremities that pass between keratinocytes and are called intra-epidermal free nerve endings (FNEs), are the exclusive detectors and transducers of noxious thermal, mechanical or chemical stimuli  ion channels as the pivotal sensors for nociception, which are involved in both acute pain and inflammatory pain. Since the subject of this review is the contribution of keratinocytes to nociception, we will focus our discussion on these receptors that are also, for the most part, expressed by keratinocytes.in vivo , expressed by peptidergic C- and Aδ-fibres  express functional sensory receptors activated by noxious stimuli and (2) induce the release of neuroactive substances that (3) specifically activate nociceptive sensory neurons to ultimately elicit pain. Several arguments explain that the concept of keratinocytes as noxious sensors has only recently emerged. First, for several decades, the dogma underlying cutaneous somatosensation stated that nociceptive sensory neurons were the sole cutaneous nociceptors, thus discouraging the emergence of alternative view. Second, functional receptors harboured by epidermal keratinocytes and classically implicated in noxious perception when expressed by sensory neurons, such as TRP ion channels that include TRPV1 , provides a first argument for the contribution of this keratinocyte-expressed channel to noxious perception , which are essential to triggering action potential firing, but also involved in the pathogenesis of neuropathic pain  that underlie(s) the sensory dialogue between epidermal keratinocytes and sensory neurons. In the Merkel complex, synaptic contacts between Merkel cells and Aβ-fibres ensure the speed and specificity required for communication (Haeberle et al.,