Background: The potential use of manikins made of environmentally friendly materials (biodegradable or easily recycled) could be a milestone in promoting cardiac arrest awareness and mass resuscitation training without the threat of generating large amounts of unprocessable waste. The main aim of the study was to compare the attitude of young adults from Asia and Poland towards cardiopulmonary resuscitation training forms and to evaluate the innovative concept of an ecological resuscitation manikin; Methods: This was a survey-based study conducted during two events in Thailand and Poland in 2023; Results: A total of 226 questionnaires were included in the final analysis. Asian respondents were significantly more likely to choose traditional training than Polish participants . A manikin that is mainly biodegradable was the most common choice across the entire study group. Young Asians were significantly more likely to choose a traditional stationary course, while Polish respondents were highly significantly more likely to opt for hybrid training . Conclusions: In the total study group, young people from Poland and parts of Asia are most likely to participate in traditional on-site instructor-led training, but a comparison across groups showed a significant tendency for young Poles to choose a hybrid training option, i.e., a combination of online and hands-on training. Despite some differences, both study groups showed a strong interest in pro-environmental behavior and the use of more ecofriendly solutions than previously used in resuscitation training. Despite the progress made, mortality in out-of-hospital cardiac arrest (OHCA) remains very high ,2. WhileWith regard to survival, the undertaking of CPR by an SCA bystander plays a crucial and undeniable role in increasing the chances of survival. Moreover, it is one of the few factors that also contribute to a good neurological outcome ,12,13,14The subject of the presented study is novel since it connects issues highly important from the perspective of human life and public health with a broader perspective related to ecology and the environmental safety of the planet. Research is increasingly involved in assessing the attitudes of different social groups towards the daily use of organic products ,24, inclThe main objective of the study was to compare the attitudes of young adults from different parts of Asia (AS group) and Poland (PL group) towards CPR training and to evaluate a novel concept for a CPR training manikin made of environmentally friendly materials. preferred form of CPR training;preferred manikin in terms of materials used for its construction;respondents’ attitudes to a manikin made of ecological materials and its usefulness in mass CPR training.The specific objectives were to assess and compare the following variables across study groups: This survey-based study was conducted during the first official presentation of the ecological CPR training manikin . Stage 4.—Evaluation of the content by subject matter experts , minimum (Min), maximum (Max), percentage (%) and standard deviation (SD). The results for responses to the questions “In scale 1 to 5 how the ecological safety of our planet is important for you?” and “How do you rate the manikin in terms of usefulness in CPR training and mass CPR training?” were compared using the Mann–Whitney U test, depending on the group. The results of the answers to the questions: “Do you think it is important to use ecological products in everyday life?”, “What type of CPR course would you choose if you had a choice?” and “What type of manikin for CPR training would you choose if the cost of training and the functionality of the manikin were similar?” were compared using the chi2 correlation test and the Fisher’s exact test, depending on the group.p value < 0.05 was considered significant and a p < 0.01 was considered highly significant.A A total of 235 participants took part in the study. After rejecting nine questionnaires due to incomplete data, 226 questionnaires were included in the final analysis. There were 91 respondents (AS group) from Asia and 135 from Poland (PL group). The mean age of the respondents was 18.9 ± 3.4 years and did not differ significantly between the groups . Respondents in the AS group came from different countries .p < 0.01). Analysis of the respondents’ answers to the question “Do you think it is important to use ecological products in everyday life?” also showed a statistically significantly higher frequency of an affirmative answer among the Asian respondents . The vast majority of respondents would like to take part in CPR training in the future. In this case, there were no significant differences between the study groups . AS respondents were significantly more likely to choose traditional training than PL participants . None of the PL respondents expressed a preference for exclusively online training, which was chosen by 9.6% of AS respondents  clearly dominated across the entire study group and the individual AS and PL groups . Howeverpondents .p = 0.250). A manikin, which is mainly biodegradable, was the most common choice across the entire study group, whereas a traditional manikin made of mostly non-recyclable plastics was the least frequent choice . The Asian respondents were also highly statistically significantly more likely to indicate that they believe it is important to use organic products in their daily lives. All of the young Asians surveyed agreed that this was important for them. Although concern for this issue and product choices among the Polish respondents were also high, this aspect was not important for almost one in ten respondents. The results of the survey showed that young people from both Poland and Asia declare concern for environmental welfare. These results are interesting in that the two groups of respondents come from very different cultural, economic and social backgrounds. Since these respondents were young adults, who were just entering their productive years and would themselves be responsible for shaping the attitudes of future generations, the results obtained may seem all the more optimistic from a future perspective ,25,26. Sp = 0.713), which also seems to be consistent with these declarations. In this case, however, the difference was not statistically significant. Statistically significant differences were also not found between the Polish and Asian groups in terms of their responses to the question about which manikin, from the perspective of the materials used in its construction, they would like to train on. Among all participants in the study, the most commonly selected type of manikin was (in order): mainly biodegradable, recyclable, traditional—which, according to the available specifications of some manufacturers, is commonly made of materials such as: polyvinyl chloride (PVC), low density polyethylene, rubber, silicone, etc., [The evaluation of the concept and the ecological manikin in terms of usefulness in CPR training and mass CPR training showed a higher score on a five-point scale for respondents from the Asian group , but practical training is provided at the student’s home. Due to the need to keep the questionnaire as short as possible and tailored to the type of events during which it was conducted, the reasons for such choices were not analyzed. At the same time, regardless of the form chosen by the participants, it should be borne in mind that any of them may be beneficial even if they are dependent on the target group and technical, organizational, and financial capabilities ,18,45. ATherefore, in the current study, we wanted to find out what the attitude of young people is towards the preferred form of training, the type of manikin, and to assess the possibility of using the presented prototype for CPR training and mass CPR training. Especially since many concepts are currently being developed. Some of these strive for extremely high training credibility, which may involve the use of non-ecological materials. Others transfer participants, using electronic systems and computers, into virtual reality or augmented reality. Our study aimed to check whether, in addition to such sophisticated tools, simpler but fully ecological ones could potentially gain recognition among young people. Especially since the potential use of ecological and low-cost solutions in resuscitation education can potentially be applied in many ways. In addition to standard training in small groups, this could create new opportunities for mass CPR training or hybrid methods (online with hands-on training). This last example may be particularly applicable in exceptional situations such as a lockdown during a pandemic ,41,42,43It should also be remembered that, in relation to improving the quality of care in SCA and the implementation of CPR skills, measures and solutions known and obvious in one region may be unavailable in another region of the world. An International Liaison Committee on Resuscitation statement on cardiopulmonary resuscitation in low-resource settings reveals primary action points on that matter. In the education category, the statement suggests considering alternative teaching approaches such as distance, virtual, hybrid, and blended-learning methods, and low-cost mannequins . Most imFuture research should focus on the difficult task of finding the right recipe to meet diverse needs. Including, among other things: effective training methods and techniques and equipment enabling their implementation, and methods of organizing courses/mass training sessions so that they reach entire societies regardless of age group and economic balance. The present work also draws attention to additional aspects of that challenge, such as environmental sustainability and the human factor in shaping the method of training and the equipment used. Educators, designers, producers as well as researchers should also take into account whether a given training method will be well received by the target participants themselves. The attitude and general emotions experienced during the process of acquiring knowledge are important factors in remembering what we learn. Despite some differences, even those statistically significant, the results of the survey among young people from Asia and Poland can be considered to be very optimistic. Their opinions may differ due to cultural, economic, religious, social or political factors, but in these most important respects, they reinforce a belief in progress in terms of awareness in two important dimensions: saving lives and striving for practical application of eco-friendly solutions, even in unusual applications.The relatively small number of respondents representing the comparison groups in the analyses was the main limitation of the study. The nature and aim of the study, as well as the unusual issue addressed meant that the analysis of the minimum size of the respondent groups had to be limited to participants of the two events who had the opportunity to closely familiarize with the ecological manikin. Additionally, the respondents may not be fully representative of the age group since their participation in the events at which the survey was conducted may have influenced their general preferences, opinions or attitudes towards the issues raised in the questionnaire. The questionnaire itself, being short and simple, was therefore not fully evaluable, which may have limited its power. In the case of the AS group, the diverse backgrounds of the respondents in terms of their country of origin may have been an additional limitation affecting the heterogeneity of the group.In the total study group, young people from Poland and parts of Asia are most likely to participate in traditional on-site instructor-led training, but a comparison across groups showed a significant tendency for young Poles to choose a hybrid training option, i.e., a combination of online and hands-on training. Despite some differences, young people from Poland and Asia showed a strong interest in pro-environmental behavior and the use of more eco-friendly solutions than previously used in CPR training.


Women scientists have made many contributions to the scientific arena regarding human health and diseases. They have made great efforts to reveal the secrets in the science of immunology, developing new experimental methods and showing effective treatment alternatives. While focusing on the mysteries of the defense systems of many living organisms in nature, women scientists have adopted the principle of pursuing their vital interests. Women scientists have made significant advances in genetics, molecular biology, microbiome, genomics, imaging, responses to infectious diseases, drug development, and identification of genetic disorders underlying primary and secondary immunodeficiencies –4. We arIncreasingly, women have risen to leadership positions in areas such as laboratory supervisors, study protocol leaders, institute directors, university rectors, foundation and association presidents, and pharmaceutical company CEOs.Of the more than 700 laureates of a Nobel, only 30 have been received by women. The first woman to receive a Nobel Prize was Marie Curie with her spouse for their work on spontaneous radiation. Lastly, Tu Youyou received Nobel Prize in Physiology or Medicine in 2015. She demonstrated the effectiveness of Artemisinin in malaria cases resistant to chloroquine treatment, and it is thought that she signed one of the most critical pharmacological discoveries of half a century because of this success.Rosalind Elsie Franklin (1920 –1958) was a British chemist whose x-ray diffraction studies provided crucial clues to the structure of DNA and quantitatively confirmed the Watson-Crick DNA model. Her work was essential to understanding the molecular structures of DNA, RNA, viruses, coal, and graphite. She photographed the double helix structure of DNA. Unfortunately, Franklin’s contributions to the discovery of the structure of DNA were largely unrecognized during her life. It has been suggested that Franklin would have ideally been awarded a Nobel Prize in Chemistry, along with Wilkins, after her death. Throughout her 16-year career, Franklin published steadily: 19 articles on coals and carbons, five on DNA, and 21 on viruses.Barbara McClintock (1902 –1992) was an American scientist and cytogeneticist who was awarded a Nobel Prize in Physiology or Medicine in 1983. She demonstrated the role of the telomere and centromere, regions of the chromosome that are important in the conservation of genetic information. Her work has been considered one of the top two great discoveries in genetics.Rita Levi-Montalcini 1909-2012) was an Italian neurobiologist. She was awarded the 1986 Nobel Prize in Physiology or Medicine jointly with colleague Stanley Cohen for the discovery of nerve growth factor (NGF) in 1986. NGF was the first of many cell-growth factors found in animals’ bodies, causing tumors. It plays an essential role in the growth of nerve cells and fibers in the peripheral nervous system. She held the position of Director of the Institute of Cell Biology of the Italian National Council of Research, From 1969 to 1978  assesses people’s attitudes toward women’s roles in various areas of life in four key dimensions: political, educational, economic, and physical integrity. The 2023 GSNI contains data from 80 countries and territories of the World Values Survey, accounting for 85 percent of the global population. According to the GSNI, the percentage of people with biased gender and dimension is 88.45 in Turkey; however, 27.15 in the UK and 50.69 in the USA. Therefore, geography is an important factor affecting the success of women in the field of business. A woman living in the Eastern and middle eastern geography should be able to enjoy the rights that women in the Western regions have so that they can carry out original works in different habitats in various parts of the world. Prejudiced gender concepts constitute a significant obstacle to achieving gender equality and supporting all women and girls in the social and scientific arena.Turkish women scientists have accomplished successful works for the development of science in countries where laboratory and scientific research opportunities are more comprehensive than in their own countries , 10.Özlem Türeci is a German physician, scientist and entrepreneur of Turkish origin. She co-founded the biotechnology company BioNTech, which in 2020 developed the first messenger RNA-based vaccine approved for use against COVID-19 , 12. SheAnother Turkish origin scientist Mübeccel Akdis has been working at the Swiss Institute of Allergy and Asthma Research (SIAF) since 1995 and became a professor in 2015. She contributed to understanding the mechanism of skin allergies and atopic dermatitis and played a leading role in elucidating the tolerance mechanisms. Dr. Akdis has worked as a group leader of immune regulation at SIAF. Her primary research contributions are on mechanisms of allergen tolerance, high-dose allergen exposure models in humans, allergen-specific immunotherapy mechanisms, T regulatory cells’ functions, NK regulatory cells, and IL-10-producing human B regulatory cells , 14. SheDr. Gulbu Uzel is a clinical immunologist with expertise in a national and international reputation in the area of human immunodeficiency disorders from Türkiye. Her research and clinical work targeted to define the mechanisms of immune dysregulation for the inborn errors of immunity and to describe new genes altering immune responses in patients with systemic autoimmunity. She has worked at the NIH and initiated, founded, and set up the Primary Immunodeficiency Clinic at the NIH, and has discovered and described two critical human defects: PIK3CD GOF mutations leading to lymphoproliferation and immunodeficiency and CTLA-4 haploinsufficiency leading to immune dysregulation and autoimmunity , 16.To celebrate the scientific achievements and discoveries of the world’s pioneer female immunologists, we feature reviews that cover the latest research and advances in immunology written by leading female scientists. With this Research Topic, the section on Primary Immunodeficiency of Frontiers in Immunology offered female scientists the opportunity to promote their work by publishing original studies or reviews that address challenging issues in the field of inborn errors of immunity.Despite various challenges and obstacles, women in science have made significant contributions throughout history. The successes of influential personalities such as Marie Curie or Özlem Türeci will pave the way for the next generation of women in scientific fields. Their existence and the strength of their struggle continue to inspire women in scientific disciplines worldwide.To sum up, women have contributed in many areas, from demonstrating immune cell differentiation and function to developing innovative technologies and creating new algorithms in diagnosis and treatment. The increase of successful women in science and medicine in recent years is a great honor for societies. While progress has been made in overcoming these obstacles over the years, much work still remains to be done to achieve gender equality in science. Special projects and foundations are needed to increase the visibility of female immunologists. Platforms of female immunologists can be helpful to ensure that women are nominated as speakers, chairpersons, and committee members at immunology-related meetings and the editorial boards of journals as experts in decision-making bodies. The presence of leading female authors in the fields of immunology and immunodeficiency in recent years is a source of pride for their countries and societies. For this reason, projects that will highlight the role models of such women and enable them to be recognized by the community should be implemented in a short time.History has shown with examples of the difficulties experienced by all women who contribute to the scientific arena and that they should make more efforts in this field than their male colleagues. In this article, I tried to give examples of women who received awards for their work or who shed light on immunology with their groundbreaking innovations. Some suggestions were made about what to do in order for women to show themselves in the field of science, and ideas were put forward on how to pave the way for women.SK: Writing – original draft.


Upper Palaeolithic sites in southwestern France attributed to the Upper Gravettian and the Solutrean yielded sub spherical gravels with a highly shiny appearance that have intrigued researchers since the 1930s. In this work, we analyze specimens from five sites, including the recently excavated Solutrean site of Landry, to establish whether their presence in archaeological layers and peculiar aspect are due to natural processes or human agency. We study the spatial distribution of gravels at Landry and submit archaeological gravels from the five sites, natural formations, Landry sediment sieving, and polishing experiments with a rotary tumbling machine to morphometric, colorimetric, microscopic, and textural analyses. Our results indicate the lustrous gravels found at the five sites result from deliberate selection and suggest their shiny appearance is the consequence of human agency, possibly resulting from prolonged contact with a soft material such as animal skin. Ethnographic accounts indicate that these gravels may have been used for magico-religious ritual purposes , in games, as elements of musical instruments, and as items serving other social and personal purposes. We argue that these objects reflect a cultural innovation emerged during the Gravettian and continued into the Solutrean. Upper Palaeolithic sites in southwestern France attributed to the Upper Gravettian and the Solutrean have yielded sub spherical gravels with a highly shiny appearance that have attracted the attention of Palaeolithic archaeologists since the 1930s . PeyronyAnswering these questions has been made difficult by the fact that these gravels were uncovered during excavations for which we lack relevant contextual data. We do not know, for example, whether gravels were systematically collected nor do we have precise information on their spatial distribution and eventual association with other archaeological remains. The discovery of about a hundred lustrous gravels on the recently excavated Solutrean site of Landry  , and the application of new analytical methods make it possible to approach the question of the origin and eventual anthropogenic modification of these objects in new ways.In order to address this topic we combine in our study four approaches: 1) spatial analysis of lustrous gravels and their relationship with other archaeological remains unearthed at Landry, 2) morphometric and colorimetric analysis of gravels discovered at this site, four other Upper Palaeolithic sites from Dordogne, and gravels from geological deposits accumulated by known sedimentary processes, 3) surface texture analysis of lustrous and non-lustrous gravels from archaeological sites and natural accumulations as well as gravels experimentally polished to mimic natural and anthropogenic actions, 4) microscopic analysis of the natural, archaeological and experimental gravels, and 5) a survey of ethnographically-attested uses of gravels and small pebbles. The objective of the spatial analysis was to establish whether the gravels’ distribution was random or not, and connected with that of other archaeological remains. The morphometry and colorimetry of the lustrous and non-lustrous gravels aimed at verifying whether the former represents a selection of the gravels naturally available on the site. The textural analysis of archaeological, natural and experimentally polished gravel was intended to document and quantitatively compare their wear patterns to establish whether shine on archaeological objects could be found in nature, and which experimental polishes generated by a tumbler and a metallographic polisher better mimic archaeological wear. The microscopic analysis, conducted at different magnifications, was aimed at a more finely tuned characterization of natural, archaeological and experimental gravel’s surface conditions and intra-site comparisons.The last decade has seen a substantial development of studies applying confocal microscopy and roughness parameters to archaeological artifacts with the objective of understanding the function of tools, the intensity of use, and taphonomic processes affecting the artefact after its production and use –17. The Lustrous gravels are reported from four sites of the South-West of France: Fourneau du Diable, Casserole, Pech de la Boissière and Laugerie Haute . The recMB excavated in 2011, Landry is an open-air site located close to Boulazac, Dordogne, France . The sitSpatial analysis identified five distinct concentrations of artefacts  spread oThis site is located on the right bank of the Dronne River, near Brantôme, Dordogne, France . It consLocated near Carsac-Aillac, Dordogne, France , the Pec14C AMS on burned bones to 20.5–23.3 cal BP  was performed . The search was restricted to the 186 Standard Cross Cultural Sample (SCCS) cultures, a subset of eHRAF with the most detailed and robust ethnographic descriptions. This yielded 23022 paragraphs across 175 cultures. The eHRAF Outline of Cultural Materials (OCM) has subject codes tagged to each paragraph. The top five for this search were Sacred Objects and Places, Prayers and Sacrifices; Mythology; Literary Texts; Spirits and Gods. Utensils, Tools, Weapons, and Burial Practices were in the top 20. Because each paragraph is usually tagged with multiple OCM codes, we developed a bespoke coding scheme for specificity.To explore historical and contemporary uses of small stones similar to the lustrous gravels examined, FMJ used the electronic Human Relations Area Files (eHRAF), a collection of full-text, subject-coded global ethnographic materials  was read and coded for how pebbles were used. FMJ noted if pebbles were present in multiples of four or more at one time , and any information about bags or other carrying items. We did not code keyword mentions that were irrelevant to our study, especially where stones were described as larger than a fist  or when the keywords were associated with technologies not relevant for our study . Other rare mentions, such as being described in fantastical folklore, or stones referring to the seeds of fruit, were also not assigned to a code.Lustrous gravels are concentrated in squares R11, R12, and Q11, sector 3, and to a lesser extent in adjacent squares . A few gThe spatial distribution of flints and metamorphic rocks appears strongly correlated with that of the lustrous gravels . As indiMorphometric analysis identifies significant differences (p < 0.05) see  between The archaeological lustrous gravels are characterized by homogeneous surfaces on which depressions are either absent, or rare and of dimensions not exceeding 10μm. Curved micro-cracks corresponding to incipient fracture cones are also discernable . The edgAt higher magnification, the surface of all natural gravels and those recovered in the sieving at Landry retain a rough appearance associated with micro concavities ranging from 20 to 100 μm in length . Rare luRoughness parameters identify significant differences (p < 0.05) see  between The principal component analysis of all recorded parameters  highlighAs expected, all experimental treatments significantly reduced the roughness of the gravels. The tumbling process, entailing impact of the gravels on each other and their contact with the skin, causes a gradual flattening of the surface resulting in a shiny appearance . AbrasioUses were first documented at a low level (e.g. “as luck charm”), and then on completion of the sample, our coding system aggregated initial categories into a higher level , as described in In the full sample, ritual uses  were the most commonly described (n = 44), followed by games (n = 25) and music (n = 18). A range of other uses accounted for the remainder. Hunter-gatherer societies differed in the most common use  but followed the trend for music (n = 11), ritual (n = 10) and games (n = 9) as most common . Eating/Polished pebbles have been found repeatedly at archaeological, including ancient, sites , 68. FewThe geoarchaeological study of the Landry site indicates that the spatial distribution of archaeological remains has not been marginally affected by post-depositional disturbances . Landry At all the analyzed sites, what makes the gravels peculiar is also their shiny appearance. Since the mode of formation of the sedimentary layers is not different at Landry between the concentrations and the areas outside them, there is no reason for thinking that the site formation processes could have affected the gravels inside and outside the concentrations in a different way and create a gloss only on the former. No evidence of chemical alteration or a similar gloss is observed on the remainder of the archaeological remains found inside the concentrations of artifacts , 22. TheIn summary, the roughness analysis of natural, experimental and archaeological gravels supports the hypothesis that after being selected by their size and shape, the archaeological gravels were subjected to a human action that has strongly polished them.The differences in roughness observed between the lustrous gravels from Landry and other archaeological sites may be due to the fact that 1) only the most lustrous gravels were collected in early excavations; 2) at Landry non- or low-gloss gravels were naturally present in archaeological concentrations, which created a sample that included both lustered and non-lustered gravels; 3) the activity that lustered the gravels at Landry was not as extensive as at other sites; 4) their mineralogical composition is different, the Landry gravels could not reach the degree of lustering observed at other sites, where the gravels are composed of other rocks, while being subjected to the same modifications. Selective collection of gravels from older excavations is possible, but two of the collections examined were from recent excavations in which the sediment was systematically sieved with water. The degree of luster of the gravels from these sites is not substantially different from that observed in the ancient collections, which contradicts the hypothesis of selective gathering. The possibility that the rock of which they are composed may determine the lower luster of the Landry gravels seems partly contradicted by the fact that the experimentally tumbled gravels, composed of quartz, attained a degree of luster similar to that observed on the lustered gravels from other archaeological sites. Although it is difficult to rule out the possibility that some of the discarded factors may be a contributing factor to the differences in luster between Landry and the other sites, the most likely hypothesis appears to be that the luster on the Landry gravels is either the result of the same action to which the gravels from the other sites were subjected, but for a shorter period of time, or the result of a slightly different action.Microscopic analysis of archaeological, natural and experimental gravels provides essential additional elements for documenting and interpreting the differences between these groups. On the one hand, it confirms that the wear pattern present on archaeological gravels is absent on natural gravels, which further supports its anthropogenic origin. On the other hand, it reveals that the shine observed on the archaeological gravels, similar in terms of roughness values, include in reality at least two major categories of wear, one characterized by the presence of striated areas and the other by their absence, incipient micro fractures and large homogeneously lustered areas with rare crisscrossing striations. The first category results from directional rubbing of the gravels against a surface rich in abrasive particles of variable size, the second from repeated contact with objects of same hardness than the gravels in an environment with very few abrasive elements. This last wear pattern is comparable to that observed on tumbled gravels, which show, however, as documented by texture analysis, a slightly less developed shine. These two wear patterns are consistent with 1) intentional rubbing of the gravels against a variety of slightly abrasive materials with or without the adding or abrasive particles, and 2) prolonged tumbling of numerous gravels in leather containers to polish or transport the gravels. The differences observed in the first wear pattern can be attributed to the materials against which the gravels were rubbed at different archaeological sites, the motions involved and the state of preservation of the wear pattern. The local disappearance of striations on some gravels may result from transport of previously intentionally polished gravels or taphonomic processes. The variability observed in the second wear pattern may have resulted from the type and treatment of the soft materials used for the containers in which the gravels were tumbled or transported.The long duration of the tumbling experiments necessary to produce a luster similar to the one observed on the archaeological specimens seems to contradict the hypothesis that sporadic contact with soft material or human skin, for example when handling the gravels, may have produced such a developed luster. In summary, results from textural and microscopic analyses concur to identify the lustrous appearance of the archaeological gravels as resulting from intentional polishing, producing oriented striations, probably aimed at making the gravels shinier, and their transport. This hypothesis is consistent with results of texture analysis indicating that although not significantly different from that recorded on the experimentally tumbled gravels, the luster on most archaeological collections reach substantially higher degrees.These results do not allow us to identify with certainty the function for which the gravels were intended. The luster may, for example, be the result of polishing by abrasion to increase the gravels’ lustrous appearance tumbling in leather containers to obtain a similar effect or transporting the gravels from one site to another. Intentional polishing may have been instrumental, for example, to create visually catching ornaments, as suggested by Peyrony or to use the gravel to play. It is less probable that gravels were intentionally polished with the aim of putting them in a container to produce a rhythmic sound. The actual function may have produced little or no luster.It is worthwhile for this reason to turn to the ethnographic and archaeological record. The former may inform us on the uses of gravels in different traditional human cultures. The latter may identify cases in which contextual information would allow us to understand the function that gravels had in past populations. Both records open the possibility of analyzing in the future, with the same methodologies applied in our study, ethnographic and archaeological gravels and compare the results of these analyses with ours.Our ethnographic survey shows that the most common functions for small pebbles are magico-religious ritual uses, and as game pieces. Worldwide, pebbles are used as talismans, amulets, and charms –72 see .While many of the ethnographically attested functions imply a choice of gravels on the basis of size, shape, weight and raw material criteria, exact remarks on size were uncommon in the sources. Anthropologists occasionally noted qualitative features such as color or shape e.g. “marble-like stones” , “preferThe results of our study indicate that there are means to distinguish objects modified by natural processes from artifacts minimally modified by humans. Use-wear analysis has been widely applied to prehistoric artefacts to identify their function. However, this approach has been implemented on artefacts recognized as the outcome of human agency. In our case, instead, we have faced the challenge of identifying such agency exclusively from surface modification. The chosen means to pursue this endeavor involved evaluation of contextual data, creation of natural and experimental frames of reference, and characterization of natural, experimental and archaeological material using multiple, adapted analytical tools. These analyses leave no doubt: the lustrous gravels discovered in several Gravettian and Solutrean sites in southwestern France were lost or abandoned in these sites after having been selected on the basis of size and shape criteria and having been involved in specific activities that produced their lustrous appearance. These gravels were not discovered in older Gravettian layers during the numerous excavations conducted in the region despite the fact that many of these excavations were conducted in recent times, with modern excavation techniques and by archaeologists aware of the possibility of discovering glossy gravels in Upper Palaeolithic archaeological layers. This leads us to conclude that the activity in which the gravels were involved, which is impossible to identify precisely but could involve a long-time use or curation in a leather bag, reflect a cultural innovation that developed during the Gravettian period and continued into the Solutrean period at the least.S1 TableRegion, Culture, Outline of World Cultures (OWC) code, Subsistence Type*, Source, Page, Focus Date, Outline of Cultural Materials (OCM) Subject, and Paragraph are taken direct from eHRAF. Focus Date is the earliest given in the source, or when not given, the publication date. Use denotes a low-level classification of the use. Coded Use is the final code given in the text. Multiples refers to if pebbles were present in multiples of four or more at one time . Notes carries any pertinent information about bags or other carrying items, and qualities of the stones . Subsistence Type: AP Agro-Pastoralists, HG Hunter-Gatherers, HC Horticulturalists, IA Intensive Agriculturists, OSC Other Subsistence Combinations, PA Pastoralists, PHG Primarily Hunter-Gatherers.(XLSX)Click here for additional data file.S2 Tablehttps://osf.io/9wpn7/.R script and data to produce Figs (XLSX)Click here for additional data file.


Antibiotic use in aquaculture has become very controversial vis-à-vis driving antimicrobial resistance (AMR) in aquatic bacterial populations. The AMR trends in fish pathogens in Hong Kong over a four-year period suggests that providing small stakeholder farmers with free veterinary advice on fish health issues and treatments, as well as subsidized quality-assured medicines, likely reduced AMR. We observed a dramatic reduction in the proportion of bacteria resistant to oxolinic acid, oxytetracycline, and florfenicol on local aquaculture farms between 2018 and 2021. These decreases coincided with either a change in antibiotic use practices on farms (i.e. with oxytetracycline), or the reduction in the use of specific drugs (i.e. oxolinic acid and florfenicol). We did not observe a similar decline in the resistance pattern to commonly used antibiotics in human medicine in the same fish bacteria. Resistance to these products, which were unlikely to be used by the farmers in our study, was very high. Our finding suggests that both human and veterinary use of antibiotics in Hong Kong may have an influence on the AMR of bacteria in the aquatic environment. Although the use of antibiotics in this industry is not the only factor driving AMR in aquatic bacterial populations, it likely plays a role in the global increase of antibiotic resistance. Most countries have regulations in place to limit the use of medicines in food animals7, and many have developed strategies and guidelines for the prudent use of antibiotics in different health sectors, including veterinary medicine for aquatic animals. Despite this, changing the mindset of health professionals and farmers is difficult, especially when alternatives to antibiotics are few, and often not as cost effective in controlling fish mortalities in the face of bacterial disease outbreaks. It is also difficult to enforce regulations on antibiotic use in aquaculture, and relatively easy for a layperson to purchase drugs in many places, particularly in low- and middle-income countries10. Many of these products are available on-line without a prescription, and can be hand-mixed on farms when the quantity of feed used is low. Further, surveillance for drug residues in fish products sold locally, especially in live fish markets, is often limited, so it is difficult to penalize individuals who do not comply with regulations on the use of these substances.Antibiotic use in aquaculture has been linked to antimicrobial resistance (AMR) issues in aquatic ecosystems11. It is also evident that environmental leaching of top-coated drugs occurs13. Another issue that has become apparent in the last decade is the sale of fraudulent drugs, which contain lower concentrations of active compounds than stated on their labels14. The use of these sub-optimal pharmaceutical products results in under dosing, a practice known to increase the risk of AMR16.The use of antibiotics in fish does not directly negatively impact the animals, and it may help when fish are infected with a bacterial pathogen, so this is sometimes seen as a treatment option when fish are dying. Unfortunately, as researchers learn more about metaphylactic treatments in aquaculture, it is becoming apparent that delivering medication effectively to large populations of fish is complicated and requires careful execution to ensure proper dosing of the fish17, there are limited numbers of fish health experts to assist farmers with disease diagnostics and provide advice on appropriate mitigative strategies for control fish mortalities. In some settings, farmers rely on previous experiences or the farming community’s advice for treatment options. These suggestions are often done with minimal diagnostic work-up other than gross evaluation of dead fish. This type of diagnosis is not accurate, given that many fish diseases appear similar on gross examination of animals. Further, in some cases, those recommending the antibiotics may profit from the sale of these medications , which may lead to promoting their use.In many aquaculture industries, particularly for small farm operators in low- to middle-income countries, which make up a significant portion of the aquaculture industry in Asia18. Prior to the establishment of the AVES at CityU, there were no aquaculture veterinary specialists to help Hong Kong fish farmers with medical treatments. To receive service farmers call a dedicated phone line for assistance and, depending on the history and clinical presentation described on the site, the veterinarians visit and work-up the case free of charge, including conducting bacteriology cultures and sensitivity analyses when a bacterial infection is suspected, making recommendations on mitigation strategies appropriate for the situation, as well as providing quality-assured medicines at cost when justified by diagnostic tests. Over the last 5 years the service has increased in popularity among the local fish farmers. The objective of this study was to evaluate the trends in AMR in fish pathogens isolated from Hong Kong fish farms by the AVES, to determine if there were any changes in the resistance profiles over time to commonly used drugs in aquaculture and to drugs used predominantly in human medicine.To address the lack of veterinary extension services for small aquaculture farm operators in Hong Kong, the veterinary college at City University of Hong Kong (CityU) established an Aquatic Veterinary Extension Service (AVES) for local fish farmers in September 2018. This service was subsidized by the Agriculture, Fisheries, and Conservation Department (AFCD) of the government of Hong Kong, SAR, through a Sustainability Fisheries Development Fund grant. The program consisted of a veterinary consultancy service, a non-profit pharmacy, as well as education outreach on fish health issues for farmers. The types of aquaculture clients who engaged with the AVES were small-scale stakeholders with either fresh-water ponds, brackish water ponds, indoor recirculating aquaculture systems with or without aquaponics, or net pen marine systems. At the time of this study the  aquaculture industry in Hong Kong produced approximately 2900 tonnes of fish annually from inland ponds, and 330 tonnes of marine net pen fish per year19. The antimicrobial sensitivity testing of all isolated pathogenic bacteria was done using the Kirby Bauer disc diffusion method20. Antimicrobial sensitivity testing was performed according to Clinical and Laboratory Standards Institute guidelines21 with breakpoints derived from Whitman and MacNair22. The antibiotics evaluated included the two drugs prescribed by the veterinary service, oxytetracycline and florfenicol, as well as oxolinic acid, which is licensed for use in fish in some countries, and streptomycin, lincomycin, and penicillin, which are commonly used in human medicine, but never prescribed by the aquatic veterinary extension service.We extracted data from the results of the culture and sensitivity analyses done on all bacterial fish pathogens isolated from fish cases submitted to the Veterinary Diagnostic Laboratory at CityU between September 2018 and December 2021. The isolates originated from moribund fish collected by veterinarians as part of their AVES duties. Samples for bacterial isolation were only submitted when fish were suspected of having a bacterial disease. Kidney swabs were the preferred sample collected for culture purposes submitted to the laboratory. Different media  were used for primary isolation and purification of pathogenic bacteria, which were subsequently identified using MALDI-TOF MS analysis as described in Theel et al.From the extracted laboratory data on bacterial antibiotic sensitivity, the proportion of fish pathogens resistant to each antibiotic of interest was calculated for each year of the study (i.e. from January to December) by dividing the number of bacterial isolates deemed resistant to the specific antibiotic by the total number of bacteria evaluated during the same time period. These proportions were expressed as percentages and depicted graphically over time. In the case of lincomycin, resistance to this lincosamide antibiotic was only assessed in Gram-positive bacteria in the first and last year of the study. Also, in 2018, we only had data on antibiotic resistance from September to December because the veterinary service was only initiated in September of 2018.We also extracted information from the AVES database on the number of clients using the service, clinical cases seen (revisits to a farm site for the same problem were not included in this count), and the number of prescriptions given to fish farmers during the study period. These data were also summarized by year. The percent of cases treated with antibiotics was determined by dividing the annual number of antibiotic prescriptions issued by the annual number of cases. This was also described for each type of antibiotic used (i.e. oxytetracycline and florfenicol).23. For the aminoglycoside drugs, we summarized the use of streptomycin, amikacin, gentamicin, kanamycin, neomycin, paromomycin, and tobramycin. For the lincosamide drugs, we included oral and parenteral use of clindamycin and lincomycin. For estimating the use of the penicillins, we included daily defined doses (DDD) of phenoxymethylpenicillin, procaine penicillin, benzathine, benzathine penicillin, benzylpenicillin potassium, benzylpenicillin sodium, carbenicillin indanyl sodium, piperacillin, amoxycillin, and ampicillin. The use of the quinolone antibiotics included a few second and third generation drugs, specifically the DDD of ciprofloxacin, moxifloxacin, ofloxacin, and levofloxacin. Lastly, for the assessment of the tetracycline usage we included dosages of oxytetracycline, doxycycline, and tetracycline.For comparison purposes we examined the usage (daily defined dose) of different classes of drugs in both inpatients and outpatients  at hospitals in Hong Kong over the same time period as our study (2018–2021)The data used in this project originated from the Aquatic Animal Veterinary Service at the City University of Hong Kong. The Human Ethics Committee at City University of Hong Kong approved the use of the data for this project and the interviews with the practicing veterinarians (HU-STA-00000277). The veterinarians providing the service are licensed and regulated by the Veterinary Surgeons Board of Hong Kong. All veterinary services provided to the fish during the study period were subject to the approval of the owners of the fish farms. The farmers were aware that the data may be used for research purposes on an aggregated level. All data were reported in a manner that maintains the confidentiality of the clients. The funding agency for the veterinary service  also approved the manuscript for publication.https://www.chp.gov.hk/en/static/101607.html.The data collected on the antibiotic use in hospitals in Hong Kong was publicly available Aeromonas spp. (31%) or Vibrio spp. (46%). There were also a few Streptococcus spp. infections (4%) in both fresh and saltwater farms over the 4-year period.Over the 4-year study period there was an increase in the number of clients using the AVES and a gradual increase in number of cases seen by the veterinarians Table . The proThe OTC resistance pattern for bacteria isolated from fish over the 4-year period declined over time Fig. . For floHuman antibiotic use data from hospitals in Hong Kong suggested a slight decline in the use of penicillin-like antibiotics and quinolones over the 4-year study period, and an increase in the use of tetracycline and the lincosamides over the same time period Table . Based oDeciphering the role that different sources of antibiotics play on AMR in the aquatic environment has been difficult and controversial. The patterns of AMR in fish pathogens isolated from fish farms in Hong Kong provides insight into what the potential impact of using antibiotics on fish farms is on this phenomenon, and the potential role that other sources of antibiotics, unrelated to fish farming, play on AMR in the aquatic ecosystem. By evaluating the trends in resistance to antibiotics used in animals and those used predominantly in humans, we can start to see patterns that suggest both human and animal use of antibiotics influence the resistance profile of fish pathogens. Further, this study provides evidence that an aquatic veterinary extension service (AVES), which offered diagnostic services and management strategies to help reduce fish losses on small farms, and which was not dependent on the sale of pharmaceuticals for profit, may reduce AMR associated with the use of antibiotics in aquaculture.25. The pattern of resistance to florfenicol mirrored the proportion of prescriptions written for this medication during the same timeline ) that the aquatic veterinary service in Hong Kong prescribed over a four-year study period. The drug doses recommended by the veterinarians for these two drugs were based on the current recommendations by the manufacturer of these productsne Table . This an11. The veterinarians also observed farmers’ limited knowledge on how to effectively deliver medications to aquatic species. We suspect, given the practices used initially by the farming community, that sick fish may have been under-dosed and environmental contamination from uneaten medicated feed may have occurred.Florfenicol was not the only drug with an antibiotic resistance pattern that suggested the veterinary service in Hong Kong was influencing, to some extent, the AMR of fish pathogens. The reduction in the OTC AMR in fish isolates over time may reflect a more prudent use of this antibiotic by farmers under veterinary supervision. When the service started, the veterinarians observed several issues with antibiotic treatments. In the first year, farmers would call the veterinarians as a last resort when fish were already off-feed and mortality had been ongoing for some time. Antibiotic therapy when fish are off-feed results in uneven dosing and poor treatment response14. If farmers were using products without quality assuring them, this could have also led to under-dosing of animals, which has been demonstrated to promote antibiotic resistance16. Within the first year of initiating the veterinary service in Hong Kong, the veterinarians provided quality-assured drugs to their clients, so they had accurate concentrations of the active pharmaceutical ingredient. All medications were batch tested by a local commercial chemical laboratory  using liquid chromatography mass spectrometry30 to establish the drug concentration in the premixes prior to prescribing them.In a separate study in 2018, we found several sources of OTC and florfenicol that contained lower concentrations of medications than what was reported on their labelsFurther, to improve farmers’ knowledge of AMR, training on prudent use of antibiotics, which included the importance of biomass estimations, properly top coating medicated feeds, and delivering the feed appropriately to ensure the entire population was treated, was provided in 2019. Over time, the veterinarians worked with their clients to increase knowledge on how to use antibiotics to reduce under-dosing and environmental leaching, and to improve the delivery of these drugs to their fish. Each time medications were prescribed, the veterinarians worked one-on-one with the farmers to ensure the drugs were administered as prudently as possible. The slow decline in the occurrence of OTC resistance in fish pathogens, which was approximately 40% of isolates in 2018, to less than 10% in 2021, despite the increase in the number of prescriptions for this product in the industry, suggests that the extension service may have had a positive impact on the antibiotic use practices in the aquaculture industry in Hong Kong.The decline in resistance to OTC in fish pathogens could also have been associated with a decline in the antibiotic use in other sectors. To determine whether this was the case, we examined the use of this class of drug in local hospital populations, and did not observe any correlation with the resistance pattern in fish pathogens. In fact, the opposite was seen. There was an increase in the number of daily defined doses of tetracycline antibiotics used in hospital patients in Hong Kong over the same time period as our study Table , which p32, and which is available in a form that can be easily top-coated on fish feed. The AVES veterinarians made a conscious decision not to prescribe this product and, instead, provided other antibiotics to their clients (i.e. florfenicol and OTC). Prior to the implementation of the veterinary service the use of medicines on fish farms was left up to the farmers, and there was no centralized record of prescriptions used on fish farms in Hong Kong. It is likely that antibiotics were used prior to 2018; however, we could not verify this. One explanation for the dramatic reduction in resistance to oxolinic acid in fish isolates after 2018, and the continuous decline in resistance to this drug within the 4-year study period, is that farmers stopped using this product once they received advice from veterinarians and were offered alternatives to oxolinic acid. It was considerably easier, and likely less expensive to use the subsidized drugs from the veterinary service than to purchase medications without a prescription.Another antibiotic resistance pattern observed in this study that provides further evidence of the importance of prudent use of antibiotics on farms was the large decline in resistance to oxolinic acid after 2018. This drug is a first-generation quinolone, which is approved for fish use in many countriesIt is unlikely that the human use of quinolone antibiotics drove the change in resistance to oxolinic acid in aquatic fish pathogens, as the use of these antibiotics in Hong Kong hospitals only changed slightly from 1 million DDD in 2018 to approximately 950,000 DDD in 2021, based on the three quinolones we evaluated in the hospital dataset. There was a decline in the number of fish farmed in Hong Kong in 2021 due to supply chain issues , which could have influenced the bacterial resistance patterns, but it could not account for the massive drop in isolates resistant to oxolinic acid between 2018 and 2019.Unlike the patterns of resistance for antibiotics commonly used to treat fish, we did not see a similar decline in AMR towards predominantly human-use antibiotics. For example, three antibiotics which were part of the laboratory’s standard sensitivity panel, and for which the class of drugs are not available in a premix that is easy to add to fish feed , had relatively consistent or increasing resistance patterns over the study period. This point is important as it suggests the decline in the resistance pattern to the drugs used in fish was not a widespread phenomenon across many classes of antibiotics.Interestingly, the proportion of bacteria that were resistant to drugs less likely to be used in fish in Hong Kong, such as streptomycin, lincomycin, and penicillin, was very high. For example, the drug with the highest level of resistance was penicillin. Depending on the year, 70 to 90% of the fish pathogens tested were resistant to this class of antibiotic. Although it is possible that farmers used penicillin to treat fish, this antibiotic is more difficult to find in a formulation that can be mixed with fish feed. Further, the AVES veterinarians did not prescribe this medication during the study period, and there were no competing veterinary services that could have prescribed these types of drugs to fish farmers during the study period. Although it was possible fish farmers were purchasing penicillin without a prescription, the AVES was providing free veterinary service and subsidized medication to a large number of the registered fish farmers in Hong Kong so it is unlikely that many were buying drugs illegally as these products would not have been subsidized. The high and persistent resistance to penicillin in pathogens isolated on fish farms in Hong Kong suggests that other sources of antibiotics, besides those used in aquaculture, were also influencing AMR in aquatic bacterial populations.Further, this finding suggests that even if aquaculture farmers completely eliminated the use of antibiotics, the level of resistance to many of the drugs used in humans would remain very high Fig. . Resista33, so contamination of the aquatic environment is inevitable. Further, beach monitoring of E. coli counts by the Hong Kong Environmental Protection Agency also indicated faecal contamination of many sites close to the salt water aquaculture farms, with counts reaching higher than 500 cells per 100 ml at certain times of the year34. Researchers have also reported high nitrogen levels associated with sewage outflow in the region35, corroborating the a potential exposure to faecal waste and antibiotics36. Although the human use of antibiotics is no doubt much greater than the use of antibiotics by the small aquaculture industry in Hong Kong, and the level of influence of these two sources of environmental antibiotic exposure is likely proportional to their use, we believe we were able to detected a change in the resistance pattern of fish pathogens that was indicative of the use of certain products on the farms themselves.The high level of resistance to antibiotics used in humans was not surprising, as the region of Hong Kong has over 7 million people and 68 sewage treatment plants with varying levels of treatmentDespite the fact that we did not have many pathogens for monitoring AMR on fish farms in Hong Kong, and we did not include pre and post treatment samples nor environmental samples to monitor the impact of our treatments, the 4-year dataset from the veterinary service provides subjective evidence that the use of antibiotics on fish farms may influence AMR in the aquatic environment. Trends in OTC resistance suggest that despite an increase in use, the prudent use of this product may positively affect AMR in fish pathogens. Over time, as more farmers used the service, the AMR profiles for both drugs used by the industry (OTC and florfenicol) declined, and this trend was not observed for other antibiotics commonly used in human medicine. The resistance to these other drugs remained quite high throughout the study period.It is important to note that although the gradual reduction in the drug resistance to OTC and florfenicol in common fish pathogens in Hong Kong coincided with the introduction and adoption of a veterinary service, the extension service provided to the farmers had many facets, and it was not possible to attribute the findings reported in this study to any one individual activity. For example, the AVES programme worked on improving disease prevention strategies at the same time as it provided farmers with diagnostic services and treatment strategies that specifically targeted the cause(s) of their fish mortalities. The service also worked with the farmers to improve their husbandry to reduce the predisposing factors leading to bacterial infections, while treating the condition. It is important to point out that the veterinarians only prescribed antibiotics when they confirmed a bacterial disease on a farm and that they decoupled the sale of antibiotics and other pharmaceuticals from the service to eliminate any conflict of interest that might be linked to making a profit from the use of medications on farms. When non-bacterial diseases were the cause of fish mortality on farms, the veterinarians offered mitigation strategies that targeted the specific issue(s). This practice likely reduced the overall use of antibiotics, as these non-bacterial causes of death may have been treated with antibiotics in the past, when diagnostic services were limited or unavailable. The type of veterinary extension service that is described in this study takes several years to establish, as it requires farmer acceptance, participation, and trust. It was also only possible to provide this service because of a government subsidy. Without this source of funding, the small fish farm operators would not have been able to afford the service or been able to purchase high quality medication. However, if established properly, such a service may be a partial solution to reducing AMR attributable to the use of antimicrobials on fish farms.


Paraffin waxes are a promising material for heat storage with high energy density. Their low thermal conductivity, which limits the speed of charging and discharging in heat buffers, was previously shown to be improved by adding graphene nanofillers. In the present study, using molecular dynamics simulations, the segregation by molecular weight of polydisperse paraffin near graphene flakes is investigated. In liquid bidisperse paraffin composed of decane and triacontane, an aligned layer containing mainly triacontane was observed next to the graphene. Upon slow cooling, the wax crystallised into distinct layers parallel to the graphene sheet, with much stronger segregation by molecular weight than in the crystallised bidisperse wax without graphene. For polydisperse wax, the segregation effect was much less pronounced. The molten paraffin had a somewhat higher concentration of the longest chains in the first layers next to the graphene, but during crystallisation, the molecular weight segregation was only slightly increased. Measurements of crystallinity using an alternative version of the method developed by Yamamoto showed that the layers of wax were highly aligned parallel to the graphene, both in the solid state with all wax crystallised and in the liquid state with one layer of aligned wax above and below the graphene. Thermal conductivity was increased in planes parallel to the graphene flakes. The strong segregation of chain lengths in the bidisperse wax resulted in clear differences in thermal conductivity in the segregated regions. The less segregated polydisperse wax showed less variation in thermal conductivity. An important prerequisite for the ongoing energy transition is the storage of energy . This hoOne specific example of an organic PCM material is paraffin wax . BecauseMany previous studies, both experimental ,11 and mCompared to the TC of graphene (2000–4000 W/(m K) ), the obMany studies have been devoted to establishing a link between the crystallinity and thermal conductivity of polymers. For example, Borhani et al.  have stuZeng and Khodadadi  have carIn their theoretical studies, Wu et al.  and HariThe question of the molecular weight segregation of polydisperse polymer samples in the presence of nanofillers is still an open issue. It is well known that longer polymer chains have higher crystallisation temperatures ,23. UponComputational studies on the influence of paraffin–nanofiller interfaces were done by, e.g., Tong et al. . They peParaffin waxes used in practice usually are polydisperse. Knowing more about the interaction of polydisperse paraffin with graphene will provide insights into the behaviour of the composite material during melting–solidification cycles and enable further optimisation for use in heat storage. Using MD modelling, the interactions between paraffin wax and graphene fillers can be studied at the molecular scale, thereby giving information unobtainable by experiments. This is what we try to achieve in the present study.In the current paper, the influence of the graphene nanofiller on the segregation and resulting TC of the paraffin wax has been investigated. Our main goal is to have computational insights into the possible effects of the atomistically resolved nanofiller surfaces on the induced crystallisation, chain-length segregation and thermal conductivity for monodisperse and polydisperse paraffin-based nanocomposites. Segregation is quantified as the number of atoms belonging to molecules of each chain length per layer and the TC is measured by equilibrium MD (EMD), making use of the Green–Kubo formalism ,29, as wThe article is structured as follows. In In this section, we first consider the applied models for the paraffin–graphene composites and discuss measurement techniques afterwards.All simulations in the present study were performed with the fully atomistic Generalised Amber Force Field  (GAFF). us study  for the The paraffin molecules of different lengths needed to be produced separately, using AmberTools20 as described above. By combining the desired number of chains of each length, an initial configuration of the wax was produced that was very structured and had strong molecular weight segregation. To ensure a total loss of these, the paraffin was heated up to 600 K in the NVT ensemble, at which it was kept for 2 ns and then rapidly cooled down to 300 K. After adding the graphene sheet and the wax together, the composite was again heated to 600 K, held at this temperature for 2 ns and then rapidly cooled down to 450 K. This was done using the Berendsen thermostat and velocity rescale barostat at a pressure of 1 atm. Only the length of the box in the z-direction was allowed to change.Timesteps were set to 2 fs and C-H bonds were constrained using the LINCS  algorithGROMACS ,36 was uAs will be seen in Molecular weight segregation was quantified using relative densities. In each layer, the number density of atoms that were part of a chain of a specific length was determined. Dividing this by the average density (over the full simulation box) of the molecular weight under consideration, the relative density was obtained. This gives an indication of how segregated the chains of respective molecular weights are.Crystallinity was measured with the method developed by Yamamoto , altered(2σ)3  with σ tYamamoto . In addieSV [mT [K] the temperature. For ease of reading, only the definition of heat flux valid for two-body interactions is shown in Equation  measurement technique using the Green–Kubo ,29 formaJ→=1V∑ieiN of slabs. By interchanging the velocities of the coldest atom in the central slab—more specifically, slab number N/2 + 1 with N the total number of slabs—and the hottest atom in the first slab (at the edge of the simulation box), a temperature difference is induced. Once a steady state is reached, the heat flowing from the hot central slab to the cold outer slab is equal to the swapped kinetic energy,J [W/mvvm [kg] at each transfer, t [s] the total time of measurement and LLJ the heat flux [W/mAdditionally, the reverse non-equilibrium MD (RNEMD) technique developed by Müller-Plathe  was usedIn our previous publication , the TC Luo et al.  looked iThe effect of the presence of carbon nanofillers such as graphene on the thermal conductivity of monodisperse paraffin wax was studied, e.g., by Babaei et al. ,44. TheyIn Upon further cooling to 250 K, the decane has also crystallised into clear layers, as shown in The composite containing polydisperse wax at 450 K is shown in In In conclusion, a strong segregation was observed in the bidisperse composite. The presence of the graphene sheet induced the formation of much larger regions with a single chain length than was seen in the bidisperse wax without graphene. In the polydisperse composite, some segregation was present in the molten state. However, upon cooling, this did not increase as substantially as for the bidisperse wax. In comparison to the studies by Wu et al.  and HariApart from the segregation observed in bi-/polydisperse paraffin during cooling near a graphene sheet, the formation of crystalline structures is a striking aspect induced by the presence of the graphene sheet. This will be investigated next. Using a slightly altered version of the technique developed by Yamamoto , the cryIn In From previous studies ,45, it iSince, in the crystalline state, almost all molecules are perpendicular to the z-axis, it is expected that the z-component of TC will be reduced while heat transport along the xy-plane will be enhanced. Furthermore, it was shown previously ,45,46,47The most obvious method to measure TC appears to be the EMD technique using the Green–Kubo ,29 formaFurther TC measurements were done with the RNEMD technique developed by Müller-Plathe , as descIn the bidisperse composite, the same effects are observed. In the liquid state, the aligned layers close to the graphene have an increased TC compared to the fully liquid paraffin, which has a very low standard deviation in TC due to isotropy. In the semi-solid state, in which the triacontane has crystallised close to the graphene while the decane, which is concentrated further away, is still in a liquid state, there is almost a factor 2 difference in the TC of these regions. This agrees with expectation since the molecular weight and alignment are known to increase the TC ,22,45,46The polydisperse composite shows smaller differences in TC between the liquid and solid states. The molten paraffin at a large distance from the graphene shows isotropy, indicated by the very small standard deviation. The two layers closest to the graphene, the first of which has a significantly higher concentration of long molecules, as shown in In summary, in the liquid samples, alignment of the paraffin closest to the graphene sheet results in a higher TC compared to the remaining paraffin. The strong molecular weight segregation of the bidisperse wax during crystallisation results in a factor 2 difference in TC comparing the regions containing mostly long and mostly short molecules, respectively. The differences in the polydisperse paraffin were much less pronounced due to the less pronounced differences in composition.Paraffin waxes are a promising phase change material for heat storage, but significant improvement in their thermal conductivity is needed to enable fast charging and discharging. In the present study, we investigate the influence of a graphene nanofiller on the chain length segregation of polydisperse paraffin and the corresponding changes in TC. Making use of fully atomistic molecular dynamics simulations, the molecular weight segregation of paraffin as a consequence of the presence of graphene in the paraffin matrix, and the effect of this segregation on the thermal conductivity of the paraffin, were studied. With the paraffin in a molten state, a distinct layer above and below the graphene in which the paraffin molecules were highly aligned parallel to the graphene sheet was observed.Measurements of relative densities showed that this layer consisted mainly of the longer chains in the bidisperse paraffin. For the polydisperse paraffin, this effect was also observed, but found to be less pronounced, in agreement with the findings by Luo et al.  for paraA slightly modified version of the crystallinity measurement technique developed by Yamamoto , with whThermal conductivity was measured using two techniques. The equilibrium MD technique using Green–Kubo relations provided the qualitative confirmation that TC in the direction perpendicular to the graphene sheet was strongly reduced in the layered paraffin wax. Using the RNEMD technique developed by Müller-Plathe , TC was The layering in the wax implies an additional bottleneck for heat transport from graphene fillers into the paraffin and vice versa, in addition the limitation of interfacial thermal resistance between the two materials. The findings from this study provide a new direction for the optimisation of the TC of paraffin–graphene composites, suggesting to look into the functionalisation of the graphene surface.Additionally, measurement techniques for TC in the direction perpendicular to the planes of strongly layered materials could be further looked into.


This study aims to examine the existence of social solidarity during the pandemic in rural and urban areas and to know the level of community exposure to COVID-19 in Lombok Island, Indonesia. This research adopted a quantitative approach to identify and analyse the existence of social solidarity in rural and urban communities during the COVID-19 pandemic. A set of questionnaires was distributed and shared by enumerators with 1,100 targeted-respondents from Lombok Island. The survey was carried out from 14th October to 28th October 2021, that is, during a recovery period from the pandemic while restrictions implemented by the government were still in full force. Chi square statistical analysis was used to test whether there were differences in social solidarity between those who lived in rural areas and those who lived in urban areas. This research found the existence of social solidarity in both rural and urban communities during the pandemic. The level of social solidarity in rural areas is higher than in urban areas. While related to the number of those who were exposed and died, conditions were higher in rural areas than in urban areas. However, in terms of the death rate, the level of death rate in urban areas is higher than in rural areas. This condition indicates differences in the characteristics of rural and urban communities, which can be considered in implementing policies during a future pandemic. This research provides evidence for local governments in formulating policies with a social solidarity perspective by taking into account the different characteristics of rural and urban communities.The COVID-19 pandemic that has hit the entire world since the beginning of 2020 is an unimaginable phenomenon. The pandemic is disastrous because it has caused loss of life and livelihood for a large part of the population. People lose their jobs, spaces for social interaction are closed, and social relationships are disrupted. Several studies show that social solidarity should be a major concern for people to sustain the future quality of their lives. Social solidarity dimensions in this study include  The COVID-19 has turned out to be an unprecedented global health and socio-economic crisis since its emergence in early 2020  districts/municipalities around Lombok Island in the province of West Nusa Tenggara. The survey was carried out from 14th October to 28th October 2021, that is, during a recovery period from the pandemic while restrictions implemented by the government were still in full force.Lombok Island  was chosIn determining the sample size representing the population, the calculation procedure used a random proportional sampling technique  with 1.8% of respondents, Bachelor (S1/D4) with 11% of respondents, and Postgraduate (S2-S3) with 0.2 % of respondents.Based on their main daily activities, out of 1,100 respondents, 34% of respondents said they do not work, including those who have been in school, are housewives, and are retired person. Meanwhile, respondents who work as the main activity are divided into several types of work. As many as 29.2% of respondents worked as small traders, 18.5% of respondents as laborers, 16.4% of respondents as farmers/breeders, 12.9% of respondents as entrepreneurs, and the rest relied on a living from work such as non-ASN employees, ASN, private employees, fishermen, and others.According to Taylor  and Agungotong royong, (2) marriages banjar, (3) an attitude of cooperation, (4) mutual assistance, and (5) sharing of information.The following describes the results  of the rp-value that there was a significant difference in gotong royong or cooperative activities during the pandemic between rural and urban communities. Enthusiasm of people for implementing gotong royong in rural areas was higher than in urban areas. This implies that people in rural areas were less observant of prohibitions on gathering and maintaining distance during the pandemic. That is why cooperative activities such as places of worship and public facilities such as roads and public market, during the pandemic period, did not experience slowdowns, especially in rural areas. Violation of the prohibition on social distancing shows the limitation of weak sanctions and the monitoring of health protocol policies in rural areas. In a similar study, Mishra and Rath . In rural communities, respondents who answered “high” or “very high” stood at 67.7%. This shows that rural communities have a higher level of attachment to mingling and being involved in the marriage reception or banjar during the pandemic. The chi-square analysis also obtained a p-value that indicates that the difference in social solidarity between rural and urban areas was significant. In other words, it can be said that although there is a government prohibition related to the implementation of marriage banjar activities, people in rural areas were more likely to ignore them. They were more concerned with the social solidarity shown by their participation in banjar than their adherence to the health protocols set by the government.Meanwhile, respondents from urban communities for the marriage p-value of 0.00, which means the difference was statistically significant. For people in rural areas, there was a greater need to interact with each other to meet daily needs, and in terms of visiting those who are sick, they tended to ignore health protocols. In other words, government policies related to health protocols for rural areas cannot be implemented as effectively as in urban because of differences in social solidarity.This indicator of solidarity was measured based on attitudes that encourage individual actions to help others, such as borrowing money or goods and visiting sick neighbors. In general, it can be concluded, based on the results in p-value of 0.00. Again, it means that the social solidarity of respondents living in rural areas is higher than those from urban areas.In this indicator of solidarity, the willingness to help each other is measured based on donations of money or goods. Like the previous two indicators, there was again a significant difference between the attitudes of respondents from rural and urban communities in the effort to set aside money and goods for social donations. Based on the data in Health issues during the pandemic are not only based on physical health, but also has many social issues. Research Egcas et al.  shows thThe indicator of willingness to share information included shared knowledge on market prices for agricultural products, developments in agricultural technology, and detailed information on government policies related to the pandemic. For information-sharing indicators, respondents from rural areas who answered “high” and “very high” was 56.8%. Meanwhile, for the same indicator, it only reached 35.7% for respondents from urban communities. This is understandable considering that in rural communities dominated by agricultural activities, the need for sharing information should be much higher than in urban communities. The tradition of informing each other about the process and means of production and marketing of agricultural products has been long-established and is not easily influenced by external factors. From the results of this study, for example, the existence of a pandemic did not dampen the enthusiasm and motivation of farmers and other rural residents to keep sharing information. The solidarity of rural residents that has been built over the many generation is also useful for sharing current information related to the pandemic and to associated government policies. According to Jamal et al. , other fThe next part of this article is related to the number of those exposed to COVID-19. From the data released by the West Nusa Tenggara Province COVID-19 Task Force, until the end of 2021, when this research was conducted, the number of those exposed can be seen in Lombok Island is an area in Indonesia with a relatively high population exposed to COVID-19, including the number who died. From the data in Durkheim viewed changes wrought by the industrial revolution in Europe as a reference for understanding differences between more traditional societies and those that were industrializing Albrow, . Durkheigotong royong, enthusiasm for marriage banjars, cooperation, willingness to help each other, and sharing of information among residents), show that social solidarity in rural and urban areas on Lombok Island is relatively different. The five indicators can be divided into three types in order to clarify the discussion. The first type is related to gotong royong and marriage banjar, which can be described as community-based social activities and events . Based on the analysis and description above  as the basis for the glue of their mechanical social solidarity. The economic needs of rural communities on islands like Lombok are highly dependent on the agricultural sector, while urban neighborhoods with more diverse economies tend to be heterogeneous, with communication based on the expertise of the person with whom information is exchanged. Hence, in urban areas that display higher levels of organic solidarity, the pandemic more likely disrupts information-sharing because of the health protocols that the government can more readily enforce in a strict manner.The need for rural communities to share their resources reflects the pandemic's impact, which then results in greater income inequality, a widening health crises, and ultimately causing limited access to economic opportunities beyond agriculture. Physical distance restrictions on all indicators of social solidarity are translations for the ways people conduct their lives on a day-to-day basis (Paskov and Dewilde, The occurrence of a worldwide pandemic affecting every community on earth has shown how geographical distances are becoming less relevant and the shadow of globalization shows us the reflection of its impact on the daily lives of people everywhere (Mas-Coma et al., From a policy-making point of view, Durkheim emphasized the importance of law as a guiding compass for constructing social solidarity. Classification of law in Durkheim's view is divided into repressive and restitutive. The repressive rule refers to collective sanctions, while restitutive is attached to sanctions for violations. From a health perspective, preventing the spread of the epidemic using both methods is still relevant for COVID-19 (Fisher and Wilder-Smith, The future challenge is formulating inclusive but effective policies amidst the diversity of forms of social solidarity found in rural and urban settings. Furthermore, how is the communication strategy regarding the substance of the approach taken so that it can be implemented by all community members, both those who live in rural and those who reside in urban areas? From this research, it can be seen that not all existing policies can be implemented. The policy of social distancing, for example, is more difficult to implement in rural areas. Hence, this and other restrictions where the policy does not pay attention to the location of implementation will less likely be successful. Policies between rural and urban areas are generally not differentiated. Therefore, a location-specific policy formulation is needed so that if there is a failure in its implementation, the improvement of the formulation is also location-based (Sayuti et al., What is needed is collective awareness from various levels of society without exception, including policymakers in the government. The rural-urban differences in social solidarity require more in-depth research. One way to go about this kind of research is to ask how social solidarity at different kinds of places is influenced by and in turn influence things like a COVID-19 pandemic? This research provides only a glimpse at the ways the context of local places can affect the implementation of various policies during a pandemic so that they can be improved. The number of exposed and the rate of mortality could be minimized if the policies were more locality-oriented, and not simply one-size-fits-all guidelines applied uniformly and often ineffectively to diverse places.This research found that the existence of social solidarity in both rural and urban communities during the pandemic. The level of social solidarity in rural areas is higher than in urban areas. While related to the number of those who were exposed and died, from the data released by the Provincial COVID-19 Task Force, conditions were higher in rural areas compared to the number of those who were exposed or who died in urban areas. However, in terms of the death rate, the level of death rate in urban areas is higher than in rural areas. This condition indicates differences in the characteristics of rural and urban communities, which can be considered in implementing policies during a future pandemic. This research provides evidence for local governments in formulating policies with a social solidarity perspective by taking into account the different characteristics of rural and urban communities.The existence of the COVID-19 pandemic that has occurred in almost all countries has raised awareness that their level of resilience, in terms of such sociological dynamics as social solidarity, is variable. When dealing with this pandemic, attitudes or behaviors also vary according to their educational, socio-cultural background, and especially the area where they live. Therefore, by the findings of this study, we can suggest several things. First, public awareness must be improved that social solidarity must still be maintained in the face of the COVID-19 pandemic. The second suggestion is that policies related to the pandemic or other procedures in dealing with extraordinary phenomena like this must pay attention to the socio-cultural character and the location of the community's residents. The third suggestion is related to further research. Research on social solidarity needs to be repeated in the post-pandemic period. It is necessary to know whether the current study results are different or will remain the same when the research is carried out after the pandemic no longer exists.Third-party figure material in this work is used in a fair way, and the copyright holders have noted, it “Can be used for the creative projects.” in their website Therefore, third-party figure material can be used without requiring certain permissions.The raw data supporting the conclusions of this article will be made available by the authors, without undue reservation.Ethical review and approval was not required for the study on human participants in accordance with the local legislation and institutional requirements. Written informed consent from the participants' legal guardian/next of kin was not required to participate in this study in accordance with the national legislation and the institutional requirements.RS, MT, and MM contributed to conception and design of the study. SH organized the database and performed the statistical analysis. RS wrote the first draft of the manuscript. AE wrote sections of the manuscript. All authors contributed to manuscript revision, read, and approved the submitted version.