Direct Body Contact Research Articles

Social Avoidance of Mice in Pain in Naturalistic Conditions

AbstractPain and social behavior are subject to reciprocal modulation. Social animals show attenuated pain behavior in the presence of conspecifics, while observers are in turn affected by exposure to another individual in pain. Both phenomena have been established in rodents, which in addition to experiencing emotional contagion from afflicted conspecifics may act to relieve their afflicted state. Little has been done to investigate the motivation of such prosocial behavior in naturalistic conditions. Here, using a novel formalin test targeting the nape of the neck, a socially relevant area, we investigated nocifensive behaviors and social interactions in mice group-housed in a seminatural environment (SNE). In the SNE, formalin-injected mice displayed fewer back-scratching occurrences than when housed alone, which was inversely correlated to the social behavior received. These mice also emitted and received fewer social interactions, attesting of social withdrawal. With respect to dyadic exchanges, saline-treated mice initiated fewer allosniffing and anogenital sniffing episodes towards formalin-treated mice than towards other saline-treated ones. These findings are counter to those showing empathy and prosocial approach in mouse pain models. It is possible that in naturalistic conditions that allow the mice to express a wide range of their behavioral repertoire, healthy mice simply avoid individuals in pain and the cost associated with emotional contagion. Interestingly, behaviors involving direct body contact, namely allogrooming and pair-resting, were not different between saline- and formalin-treated mice and thus may carry a prosocial, altruistic component. These findings unveil new patterns of social modulation by pain in a naturalistic laboratory setting holding high translational value.

Wrestling injuries during the 2016 Rio and 2020 Tokyo Olympic Games

ObjectivesTo evaluate and compare the injuries of Olympic wrestlers during the 2016 Rio and 2020 Tokyo Olympic Games held in August 2021 due to the COVID-19 pandemic.MethodsIn this descriptive epidemiological...

Embedding textile capacitive sensing into smart wearables as a versatile solution for human motion capturing

This work presents a novel and versatile approach to employ textile capacitive sensing as an effective solution for capturing human body movement through fashionable and everyday-life garments. Conductive textile patches are utilized for sensing the movement, working without the need for strain or direct body contact, wherefore the patches can sense only from their deformation within the garment. This principle allows the sensing area to be decoupled from the wearer’s body for improved wearing comfort and more pleasant integration. We demonstrate our technology based on multiple prototypes which have been developed by an interdisciplinary team of electrical engineers, computer scientists, digital artists, and smart fashion designers through several iterations to seamlessly incorporate the technology of capacitive sensing with corresponding design considerations into textile materials. The resulting accumulation of textile capacitive sensing wearables showcases the versatile application possibilities of our technology from single-joint angle measurements towards multi-joint body part tracking.

Cases of Monkeypox show highly-overlapping co-infection with HIV and syphilis.

Ongoing Monkeypox (MPX) outbreaks in countries outside Africa have unique characteristics. However, data on cohorts of confirmed cases in China is limited. The study provides important epidemiological, diagnostic, and clinical information about this disease in China. We report a series of Chinese individuals with confirmed MPX infections identified at Beijing Youan Hospital (China) from June 10 to July 15, 2023. Samples were taken from the skin, anus, throat, and blood. An epidemiological questionnaire was used to collect demographic and clinical data. Further, we compared the MPX viral (MPXV) loads across different anatomical sites. 66 samples were collected from 20 patients, all of whom were cisgender men. Median patient age was 29 years. Notably, 19 (95%) patients reported unprotected sexual encounters with men in the preceding month, and 13 (65%) were human immunodeficiency virus (HIV)-positive. Among those with HIV, 12 (92%) were receiving antiretroviral therapy, and 11 (85%) had well-controlled infections (HIV viral load <40/mL). The median CD4+ T cell count was 667 cells/mm3. In the HIV-negative group, three (43%) patients were taking preexposure prophylaxis. Fifteen patients (75%) had concurrent sexually transmitted infections (50% had syphilis and 65% had HIV) and eight (40%) had HIV and syphilis co-infection. MPXV loads were significantly higher in samples from the skin (cycle threshold value [Ct value]: 19·0) and anus (Ct value: 23.0) compared to samples from the throat (Ct value: 31.0) or blood (Ct value: 34.5). All patients had skin lesions (85% of whom presented with anogenital lesions). Common systemic symptoms included fever (85%) and lymphadenopathy (55%). The median incubation period was 8 d [interquartile range (IQR): 6-16 d]. The median time from the onset of skin lesions to scab removal was 14 d (IQR: 10-16 d). No deaths or severe cases were reported. MPXV primarily affects young homosexual men. The high MPXV viral loads in skin and anal lesions indicate that transmission most likely occurs through direct and close body contact. This study also reports high rates of HIV and syphilis co-infection. Therefore, preventive efforts should focus on homosexual men.

Predicting partitioning from low density polyethylene to blood and adipose tissue by linear solvation energy relationship models.

The variety of polymers utilized in medical devices demands for testing of extractables and leachables according to ISO 10993-18:2020 in combination with ISO 10993-1:2018. The extraction of the materials involves the use of organic solvents as well as aqueous buffers to cover a wide range of polarity and pH-values, respectively. To estimate patient exposure to chemicals leaching from a polymer in direct body contact, simulating solvents are applied to best mimic the solubilization and partitioning behavior of the related tissue or body fluid. Here we apply linear solvation energy relationship (LSER) models to predict blood/water and adipose tissue/water partition coefficients. We suggest this predictive approach to project levels of potential leachables, design extraction experiments, and to identify the optimal composition of simulating extraction solvents. We compare our predictions to LSER predictions for commonly applied surrogates like ethanol/water mixtures, butanol, and octanol as well as olive oil, butanone, 1,4-dioxane for blood and adipose tissue, respectively. We therefore selected a set of 26 experimentally determined blood/water partition coefficients and 33 adipose tissue/water partition coefficients, where we demonstrate that based on the root mean squared error rmse the LSER approach performs better than surrogates like octanol or butanol and equally well as 60:40 ethanol/water for blood. For adipose tissue/water partitioning, the experimentally determined octanol/water partition coefficient performs best but the rmse is at the same range as our LSER approach based on experimentally determined descriptors. Further, we applied our approach for 248 extractables where we calculated blood/low density polyethylene (LDPE) and adipose tissue/LDPE partition coefficients. By this approach, we successfully identified chemicals of potential interest to a toxicological evaluation based on the total risk score.

Verletzungen in der 1. Inline-Skaterhockey-Bundesliga

Inline skater hockey is a sport originating from ice hockey, which is practised in Germany by about 6000 athletes. There are some differences to ice hockey, which lead to a special risk profile of the athletes.All 315 active players of the First German Inline Skater Hockey League in the years 2018 and 2019 were contacted to participate in an online survey. The subjects of the study completed an anonymised 83-item multiple-choice questionnaire about injuries, training frequency, training content, and sports equipment. 178 athletes responded and 116 questionnaires could be analysed (100 men, 8 women, 8 without information/16 goalies, 55 forwards, 44 defenders).The overall injury incidence was 36.98 per 1000 hours. Minor injuries (wounds, bruises, and blunt muscle injuries) most frequently comprised leg injuries (9.4/1000 hours) and arm injuries (7.2/1000 hours). Relevant injuries (fractures, dislocations, and ligamentous injuries) were most common to the foot (2.4/1000 hours) (n=147) and to the head (1.9/1000 hours) (n=140) and knee (1.7/1000 hours) (n=126). Of 76 fractures, 48 (63.2%) resulted from direct or indirect body contact. Goalkeepers suffered more knee injuries compared with field players, while field players sustained more shoulder injuries. Head injuries (fractures, dental injuries, traumatic brain injuries) were significantly more frequent in players without face protection (3.0/1000h vs. 1.8/1000h). Players who did not perform additional fitness training had significantly more relevant injuries. In this group, knee injuries occurred more frequently as well (4.2/1000h vs. 1.3/1000h). The duration of stretching exercises showed a negative correlation with overall injury incidence (0 minutes: 53.5/1000 hours, 1-4 minutes: 55.8/1000 hours, 5-9 minutes: 23.5/1000 hours, ≥10 minutes: 21.5/1000 hours, p<0.05).In particular, mild injuries occurred with a highly significant reduction in frequency if the subjects performed stretching exercises. Inline skater hockey in the First German League is characterised by a high risk of injury, which can be compared with professional ice hockey. Serious injuries are mainly caused by physical contact. Relevant injuries are most common to the head and lower extremity. The implementation of fitness training had a positive influence on the frequency of injuries. In the context of further professionalisation of this sport, these findings can contribute to the prevention of injuries in inline skater hockey.

Facial Video‐Based Robust Measurement of Respiratory Rates in Various Environmental Conditions

This paper addresses the process of respiration, which involves providing oxygen to the body’s cells, blood, and tissues. The significance of respiratory signals as predictors of diverse physical conditions, including respiratory health and disorders, is emphasized. Technologies such as pressure‐sensor belts for chest or abdominal movement detection, carbon‐dioxide sensors placed under the nose, and photoplethysmography (PPG) have been developed for real‐time monitoring of respiratory signals. However, wearable devices with direct body contact may inconvenience sleeping patients, newborns, or individuals with sensitive skin. Noncontact and noninvasive respiratory rate measurements utilizing facial videos have been explored, albeit within controlled environments. This study introduces a novel approach to measure robust respiratory signals and facial respiratory rates (FRR) using facial videos. The proposed method employs bounding box stabilization to eliminate high‐frequency components stemming from face detection. Real‐time coordinate correction is implemented to ensure accurate respiration signal calculation across varying environments. The method defines a region of interest (ROI) on the face, computes RGB data, and transforms the RGB channel into a YCgCo channel. The respiratory signal is subsequently derived by applying partial zero padding‐based fast Fourier transform (FFT) and inverse FFT (iFFT) to the Cg signal within the frequency band associated with respiration. The FRR is accurately measured by analyzing peak‐to‐peak intervals within the respiratory signal. The efficacy of the proposed method is demonstrated through a comparative analysis of respiratory rates calculated from PPG devices and facial videos across four scenarios (indoor, outdoor, car, and drone). The results highlight the reliability and precision of the suggested approach in accurately computing respiratory rates across diverse environments.

Viral loads in clinical samples of men with monkeypox virus infection: a French case series

BackgroundMonkeypox virus (MPXV) is currently spreading among men who have sex with men, outside of sub-Saharan Africa, and close contact during sex seems to be one of the key pathways of viral transmission in the current outbreak. Our aim was to describe the distribution of MPXV in the human body, as it might play a role in its dissemination through sexual contact.MethodsThe study population in this case series consisted of patients with confirmed MPXV infection attending the Pitié-Salpêtrière Hospital (Paris, France), who had been sampled from multiple anatomical sites, including skin, anus, throat, blood, urine, and semen, at diagnosis and 2 weeks later. We compared the proportion of positive samples and MPXV viral loads (given as PCR cycle thresholds [Ct]) between anatomical sites, and between day 0 (D0) and D14.FindingsOverall, 356 samples were collected between May 20 and June 13, 2022, from 50 men with a median age of 34 years (IQR 29–40). 22 (44%) of the 50 men were classified as HIV-negative on day (D)0, and 22 (44%) were living with HIV. At D0, MPXV detection was more frequent from skin (44 [88%] of 50), anus (30 [71%] of 42), and throat (36 [77%] of 47) than from blood (13 [29%] of 45), urine (nine [22%] of 41), or semen (13 [54%] of 24). Viral loads were significantly higher from skin lesions (Ct 19·8) and anal samples (Ct 20·9) than from throat (Ct 27·2), blood (Ct 32·8), urine (31·1), or semen samples (Ct 27·8). When analysing the 107 samples taken from 24 patients at D14, the proportion of positive samples strongly decreased between D0 and D14 at all sites: skin (four [22%] of 18), anus (two [9%] of 22), throat (none of 21), blood (one [5%] of 21), urine (none of 14), and semen (two [9%] of 11).InterpretationThese data contribute to a better understanding of how the virus might spread between sexual partners over a relatively short period of time. High MPXV viral loads from skin and mucosa, including genital and anal sites, suggest that transmission most likely occurs through direct body contact rather than through the respiratory route or contact with body fluids, which should help to refine the prevention messages delivered to individuals most exposed to the virus.FundingNone.

Maternal exposure to polystyrene nanoparticles retarded fetal growth and triggered metabolic disorders of placenta and fetus in mice

Microplastics can enter the human body via direct body contact or the food chain, increasing the likelihood of adverse impacts on pregnancy and fetal development. We investigated the potential effects and modes of action of polystyrene nanoplastics (PS-NPs) in placenta and fetus using mice as a model species. Maternal PS-NP exposure (100 nm; 1 and 10 mg/L) via drinking water induced a significant decline in fetal weights at the higher exposure concentration. Abnormal morphologies of cells in the placenta and fetus were observed after exposure. For the placenta, transcriptomic analyses indicated that PS-NPs significantly disturbed cholesterol metabolism and complement and coagulation cascades pathways. Metabolomics showed appreciable metabolic disorders, particularly affecting sucrose and daidzein concentrations. For the fetal skeletal muscle, transcriptomics identified many significantly regulated genes, involving muscle tissue development, lipid metabolism, and skin formation. Transcriptomic analysis of the placenta and fetal skeletal muscle at the high PS-NP concentration showed that APOA4 and its transcriptional factors, facilitating cholesterol transportation, were significantly regulated in both tissues. Our study revealed that PS-NPs caused fetal growth restriction and significantly disturbed cholesterol metabolism in both placenta and fetus, offering new insights into the mechanisms underlying the placental and fetal effects in mice exposed to PS-NPs.

Carbon-Based Coatings in Medical Textiles Surface Functionalisation: An Overview

The COVID-19 pandemic has further highlighted the need for antimicrobial surfaces, especially those used in a healthcare environment. Textiles are the most difficult surfaces to modify since their typical use is in direct human body contact and, consequently, some aspects need to be improved, such as wear time and filtration efficiency, antibacterial and anti-viral capacity, or hydrophobicity. To this end, several techniques can be used for the surface modification of tissues, being magnetron sputtering (MS) one of [hose that have been growing in the last years to meet the antimicrobial objective. The current state of the art available on textile functionalisation techniques, the improvements obtained by using MS, and the potential of diamond-like-carbon (DLC) coatings on fabrics for medical applications will be discussed in this review in order to contribute to a higher knowledge of functionalized textiles themes.

Sharing roosts but not ectoparasites: high host-specificity in bat flies and wing mites of Miniopterus schreibersii and Rhinolophus ferrumequinum (Mammalia: Chiroptera)

Schreiber's bent-winged bat Miniopterus schreibersii and the greater horseshoe bat Rhinolophus ferrumequinum are widespread and common cavernicolous species across southern Europe that host numerous specialized ectoparasite species. The objective of this study was to characterize the species assemblage, genetic diversity, and host specificity of bat flies (Nycteribiidae, Diptera) and wing mites (Spinturnicidae, Acari) found on these bat hosts in Serbia and Bosnia and Herzegovina. Notably, while bat flies lay puparia on the cave walls and can thus be transmitted indirectly, wing mites require direct body contact for transmission. Morphological identification and sequencing of a 710-bp fragment of cytochrome oxidase I gene of 207 bat flies yielded 4 species, 3 on M. schreibersii and 1 on R. ferrumequinum. Sequencing of a 460-bp small subunit ribosomal RNA fragment, in all 190 collected wing mites revealed 2 species, 1 per host. In no case was a parasite associated with 1 host found on the other host. Species and genetic diversity of flies were higher in M. schreibersii, likely reflecting their host's larger colony sizes and migratory potential. Mite species of both hosts showed similarly low diversity, likely due to their faster life history and lower winter survival. Our findings highlight a remarkably high host-specificity and segregation of ectoparasite species despite direct contact among their hosts in the roost, suggesting a defined host preference in the investigated ectoparasite species. Furthermore, the differences in ectoparasite genetic diversity exemplify the interplay between host and parasite life histories in shaping parasite population genetic structure.

A Non-Contact Compact Portable ECG Monitoring System

Cardiovascular diseases (CVDs) have been listed among the most deadly diseases worldwide. Many CVDs are likely to manifest their symptoms some time prior to the onset of any adverse or catastrophic events, and early detection of cardiac abnormalities is incredibly important. However, traditional electrocardiography (ECG) monitoring systems face challenges with respect to their scalability and affordability as they require direct body contact and cumbersome equipment. As a step forward from the large-scale direct-contact ECG monitoring devices, which are inconvenient for the user in terms of wearability and portability, in this research, we present a small-sized, non-contact, real-time recording system for mobile long-term monitoring of ECG signals. The device mainly comprises three non-contact electrodes to sense the bio-potential signal, an AD8233 AFE IC to extract the ECG signal, and a CC2650 MCU to read, filter, and transmit them. The device is powered by a 2000 mAh lithium-ion battery with isolation between digital and analog powers on the board using two low-dropout regulators (LDOs). The board’s dimension is 8.56 cm × 5.4 cm, the size of a credit card, making it optimal to be worn in a shirt chest pocket. In spite of its small form factor, the device still manages to achieve a continuous measurement battery life of over 16 h, total harmonic distortion below −30 dB across the interested frequency range, an input-referred noise as low as 1.46 µV for contacted cases and 5.15 µV for non-contact cases through cotton, and clear ECG recording for both contact and non-contact sensing, all at a cost around USD 50.

Exploring an Efficient Remote Biomedical Signal Monitoring Framework for Personal Health in the COVID-19 Pandemic.

Nowadays people are mostly focused on their work while ignoring their health which in turn is creating a drastic effect on their health in the long run. Remote health monitoring through telemedicine can help people discover potential health threats in time. In the COVID-19 pandemic, remote health monitoring can help obtain and analyze biomedical signals including human body temperature without direct body contact. This technique is of great significance to achieve safe and efficient health monitoring in the COVID-19 pandemic. Existing remote biomedical signal monitoring methods cannot effectively analyze the time series data. This paper designs a remote biomedical signal monitoring framework combining the Internet of Things (IoT), 5G communication and artificial intelligence techniques. In the constructed framework, IoT devices are used to collect biomedical signals at the perception layer. Subsequently, the biomedical signals are transmitted through the 5G network to the cloud server where the GRU-AE deep learning model is deployed. It is noteworthy that the proposed GRU-AE model can analyze multi-dimensional biomedical signals in time series. Finally, this paper conducts a 24-week monitoring experiment for 2000 subjects of different ages to obtain real data. Compared with the traditional biomedical signal monitoring method based on the AutoEncoder model, the GRU-AE model has better performance. The research has an important role in promoting the development of biomedical signal monitoring techniques, which can be effectively applied to some kinds of remote health monitoring scenario.

Perceptions and Practices of the Adult Population in Response to SARS-CoV-2 Pandemic in India

Study Objective: To find the perceptions and behaviours of the general public in response to the novel coronavirus pandemic in India. Design: An online survey was conducted during lockdown period of coronavirus pandemic. Participants: 304 respondents participated in the survey during the lockdown period of 21 days.Main Outcome Measures: Perceptions and behaviours of adult population to coronavirus infections and its prevention. Result: The mean age of the respondents was 38.38±12.34 years. Most of the respondents believed that coronavirus was a contagious infection could be transmitted via direct body contact and droplets and majority 285 (93.8%) of the respondents were aware that coronavirus is a contagious infection. Nonetheless, perceived chance of infection was found by 284 (93.4%) respondents due to public transport, mass gatherings or crowds and through contaminated food or takeaways in only 94 (30.9%). Perceived efficacy of preventive measures was social distancing (77.3%), hand washing (75.3%) and wearing a mask (48%). It is interesting to note that some people were taking multivitamin, Unani immune modulator, homoeopathic and Hydroxychloroquine medicines as prophylaxis. Conclusion: Coronavirus related perceptions and behaviours are crucial for designing preventive measures. Knowledge about the pandemic was high but misconceptions were also existed in the study group which need further improvement of appropriate IEC activities among Indian population. How to cite this article:Nazli T, Heena, Raheem A, Kishore J. Perceptions and Practices of the Adult Population in Response to SARS-CoV-2 Pandemic in India. Epidem Int 2020; 5(2): 10-16. DOI: https://doi.org/10.24321/2455.7048.202011

Pengaruh Aromaterapi Lavender secara Masase terhadap Tekanan Darah dan Tingkat Stres Mahasiswa Jurusan Keperawatan Poltekkes Palangka Raya

Stress is an individual's adaptive response to various external pressures or demands and produces a variety of disorders including physical, emotional and behavioral disorders. Final year students often experience feelings of stress so that it can interfere with concentration to attend lectures and can even hamper completing education in a timely manner. There are several ways of managing stress, one of which is using aromatherapy. Aromatherapy is a non-pharmacological therapy, which is a type of therapy that applies direct body contact and has a therapeutic effect that combines physiological effects, caused by massage on the body, with psychological effects, which are derived from essential oils. The general purpose of the study is to analyze the effect of aromatherapy on blood pressure and stress levels by using the Kessler Psychological Distress Scale in final semester students. The research method used a quasi-experimental design with a pretest-posttest control group design approach, in 28 intervention groups, namely respondents who were given lavender aromatherapy massage and 28 respondents in the control group. The univariate analysis was conducted to show frequency distribution and bivariate analysis was conducted by independent sample T-test and dependent sample T-test. The results showed that there were significant differences in systolic blood pressure before and after the intervention in the intervention and the control group with a p-value of 0.01 &lt; 0.05. Whereas the stress level variable found that there is no difference in stress levels in the intervention and the control group before and after the intervention with p-value 0.169&gt; 0.05.

Musculoskeletal injuries in taekwondo athletes: a nationwide study in Portugal.

Taekwondo is a martial art that emphasizes blows using the feet and fists, and it is characterized by direct and continuous body contact, which subjects their practitioners to a higher number of injuries. This study aimed to determine the incidence of musculoskeletal injuries in Portuguese taekwondo athletes and analyze its associated factors. The sample included 341 taekwondo athletes, aged between 4 and 62 years (18.77±12.77 years), 237 (69.5%) were male, and 104 (30.5%) female. A questionnaire was administered at a national level in taekwondo training and competitions via interview. One hundred and thirty-two (38.7%) taekwondo athletes reported having suffered an injury since they began their practice, totaling 294 injuries. Seventy-six (22.3%) athletes had an injury in the previous 12-months period, with a total of 112 injuries. There were 2.15 injuries per 1,000 hours of taekwondo training. The most common of all injuries was muscle injury (strain, contusion) (58.6%), in the foot and fingers (18.9%). The attack technique (28.8%) was the most prevalent injury mechanism. Adult athletes presented a higher risk of sustaining taekwondo-related injuries than adolescents (odds ratio = 3.91; 95%CI: 1.13-13.55; p=0.032), and athletes who trained more than 1 hour had a risk 4.20 times greater (95%CI: 1.44-12.29; p=0.009) than those who trained up to 1 hour per session. Injuries were frequent among Portuguese taekwondo athletes, with specific body areas affected, mainly caused by the attack technique. It is necessary to create injury prevention strategies, including specific training and the use of protective equipment.

The Effects of Grounding (Earthing) on Bodyworkers’ Pain and Overall Quality of Life: A Randomized Controlled Trial

It is well known that massage therapists routinely develop a number of health problems related to their profession. To determine the effects of grounding on massage therapists' quality of life and pain. Grounding, refers to being in direct body contact with the ground, such as walking barefoot on humid soil or on grass. The Chopra Center for Well-Being in Carlsbad, California, USA. Sixteen massage therapists (mean age 42.8 years). A stepped wedge cluster design was incorporated into a 6-week double-blind Randomized Controlled Trial (RCT) procedure with massage therapists assigned randomly into one of two cohorts. Therapists were not grounded for the first week, were grounded while working on clients and at home while sleeping for the next four weeks, and then ungrounded for the last week. Prior to, during, and immediately following the intervention, participants completed standardized questionnaires reporting on pain, physical function, anxiety, depression, fatigue/tiredness, sleep disturbance and number of hours of sleep, number of clients worked on per working day, energy, and emotional and mental stress. As a group, therapists experienced significant increases in physical function and energy and significant decreases in fatigue, depressed mood, tiredness and pain while grounded as compared to not being grounded. At one-month following the study, physical function was also increased and depressed mood and fatigue were decreased. We observed consistent beneficial effects of grounding in domains highly relevant to massage therapists, namely pain, physical function, and mood. These findings, combined with prior results from this trial indicating improvements in inflammatory biomarkers, blood viscosity and heart rate variability (HRV), suggest that grounding is beneficial to massage therapists in multiple domains relevant to their occupation, supporting overall health and quality of life.

Noncontact Cohesive Swimming of Bacteria in Two-Dimensional Liquid Films.

Bacterial swimming in confined two-dimensional environments is ubiquitous in nature and in clinical settings. Characterizing individual interactions between swimming bacteria in 2D confinement will help to understand diverse microbial processes, such as bacterial swarming and biofilm formation. Here we report a novel motion pattern displayed by flagellated bacteria in 2D confinement: When two nearby cells align their moving directions, they tend to engage in cohesive swimming without direct cell body contact, as a result of hydrodynamic interaction but not flagellar intertwining. We further found that cells in cohesive swimming move with higher directional persistence, which can increase the effective diffusivity of cells by ∼3 times as predicted by computational modeling. As a conserved behavior for peritrichously flagellated bacteria, cohesive swimming in 2D confinement may be key to collective motion and self-organization in bacterial swarms; it may also promote bacterial dispersal in unsaturated soils and in interstitial space during infections.

Cuticular hydrocarbon cues of immune-challenged workers elicit immune activation in honeybee queens.

Recently, evidence has shown that variations in the cuticular hydrocarbons (CHCs) profile allow healthy honeybees to identify diseased nestmates, eliciting agonistic responses in the former. Here, we determined whether these 'immunologic cues' emitted by diseased nestmates were only detected by workers, who consequently took hygienic measures and excluded these individuals from the colony, or whether queens were also able to detect these cues and respond accordingly. Healthy honeybee queens were exposed to (i) healthy, (ii) Ringer-injected and (iii) lipopolysaccharide (LPS)-injected nestmates by allowing direct body contact. Quantitative differences in the CHC profiles of these three groups were measured using GC-MS. The transcript levels of the products of four genes that encode for antimicrobial peptides (AMPs), which are part of the queen's immune response, were measured in bees exposed to direct contact using qPCR. A significant increase in the transcript levels of these AMP genes over baseline levels in queens was observed when body contact was allowed between the queens and the Ringer- and LPS-injected nestmates. These results provide the first evidence that the detection of CHCs contributes to the initiation of an immune response in insects. In an additional experiment, CHCs were extracted from diseased workers and directly presented to queens, which also evoked a similar immune response. A potential mechanism that relied on volatile compounds could be ruled out by conducting a distance experiment. The study helps to expand our knowledge of chemical communication in insects and sheds light on a likely new mechanism of social immunity.

海水浴场粪便指标菌迁移转化模型研究进展

致病微生物可以通过饮用水、食物或直接接触感染人群和动物。随着我国经济的高速发展和人民生活水平的提高、旅游度假经济的迅速发展，滨海浴场水质越来越受到人们的关注。海水浴场环境中的微生物污染对旅游者身体健康甚至生命安全有直接影响，越来越受到人们的重视。因此，了解、掌握和有效管理水环境中的微生物污染是相关行业和管理机构所面临的重大挑战之一。随着计算机和数值模拟技术的迅速发展，计算机模型技术正越来越多地被国内外国学者、工程咨询机构和环境管理部门应用于微生物污染的研究及制定相关政策的过程中。然而，我国关于海水浴场微生物污染预测模型的相关研究工作和发达国家相比相对滞后。本文对预测和管理海水浴场污染的有效工具数学模型的研究进展及应用进行研究和总结。 Human and animals may be infected by pathogens in water and food consumption and direct body contact with contaminated waters. With the rapid development of economy and tourism industry and growth in the living standard, bathing water quality in China is getting more attention. The marine tourism industry is the new growth point of economic development in China. Microorganism contamination of coastal bathing water sites is a major threat to swimmers; therefore, coastal bathing water quality is getting more and more attention. The ability to predict fate and transport of faecal bacteria in bathing waters is quite challenging to water managers and government authorities. In recent years, the developments of computing technology and numerical modeling technique have provided valuable tools for water scientists, consulting companies and water management authorities to apply water quality models to bathing waters. However, advances of research on prediction model for micro-organism contamination in China is relatively slow compare to developed countries. Here in this study, the recent advances of physical-based faecal bacteria fate and transport model were studied.