Recruitment Behavior Research Articles

Identification and functional characteristics of CHD1L gene variants implicated in human Müllerian duct anomalies

BackgroundMüllerian duct anomalies (MDAs) are congenital developmental disorders that present as a series of abnormalities within the reproductive tracts of females. Genetic factors are linked to MDAs and recent advancements in whole-exome sequencing (WES) provide innovative perspectives in this field. However, relevant mechanism has only been investigated in a restricted manner without clear elucidation of respective observations.MethodsOur previous study reported that 2 of 12 patients with MDAs harbored the CHD1L variant c.348-1G>C. Subsequently, an additional 85 MDAs patients were recruited. Variants in CHD1L were screened through the in-house database of WES performed in the cohort and two cases were identified. One presented with partial septate uterus with left renal agenesis and the other with complete septate uterus, duplicated cervices and longitudinal vaginal septum. The pathogenicity of the discovered variants was further assessed by molecular dynamics simulation and various functional assays.ResultsUltimately, two novel heterozygous CHD1L variants, including a missense variant c.956G>A (p.R319Q) and a nonsense variant c.1831C>T (p.R611*) were observed. The variants were absent in 100 controls. Altogether, the contribution yield of CHD1L to MDAs was calculated as 4.12% (4/97). All three variants were assessed as pathogenic through various functional analysis. The splice-site variant c.348-1G>C resulted in a 11 bp sequence skipping in exon 4 of CHD1L and led to nonsense mediated decay of its transcripts. Unlike WT CHD1L, the truncated R611* protein mislocalized to the cytoplasm, abolish the ability of CHD1L to promote cell migration and failed to interact with PARP1 owing to the loss of macro domain. The R319Q variant exhibited conformational disparities and showed abnormal protein recruitment behavior through laser microirradiation comparing with the WT CHD1L. All these variants impaired the CHD1L function in DNA damage repair, thus participating in MDAs.ConclusionsThe current study not only expands the mutational spectrum of CHD1L in MDAs but determines three variants as pathogenic according to ACMG guidelines with reliable functional evidence. Additionally, the impairment in DNA damage repair is an underlying mechanism involved in MDAs.

Characterising sex-related differences in lower- and higher-threshold motor unit behaviour through high-density surface electromyography.

Emerging questions in neuromuscular physiology revolve around whether males and females share similar neural control in diverse tasks across a broad range of intensities. In order to explore these features, high-density electromyography was used to record the myoelectrical activity of biceps brachii during trapezoidal isometric contractions at 35% and 70% of maximal voluntary force (MVF) on 11 male and 13 female participants. Identified motor units were then classified as lower-threshold (recruited at ≤30%MVF) and higher-threshold (recruited at>30%MVF). The discharge rate, interspike interval variability, recruitment and derecruitment thresholds, and estimates of neural drive to motor neurons were assessed. Female lower-threshold motor units showed higher neural drive (P<0.001), accompanied by higher discharge rate at recruitment (P=0.006), plateau (P=0.001) and derecruitment (P=0.001). On the other hand, male higher-threshold motor units showed greater neural drive (P=0.04), accompanied by higher discharge rate at recruitment (P=0.005), plateau (P=0.04) and derecruitment (P=0.01). Motor unit discharge rate normalised by the recruitment threshold was significantly higher in female lower-threshold motor units (P<0.001), while no differences were observed in higher-threshold motor units. Recruitment and derecruitment thresholds are higher in males across all intensities (P<0.01). However, males and females have similar activation and deactivation strategies, as evidenced by similar recruitment-to-derecruitment ratios (P>0.05). This study encompasses a broad intensity range to analyse motor unit sex-related differences, highlighting higher neural drive and discharge rates in female lower-threshold motor units, elevated recruitment and derecruitment thresholds in males, and convergences in activation and deactivation strategies. HIGHLIGHTS: What is the central question of the study? Do male and female motor units behave similarly in low- and high-intensity contractions? What is the main finding and its importance? Female motor units show higher discharge rates in low-intensity tasks and lower discharge rates in high-intensity tasks, with no differences in recruitment behaviour. A broader inter-spike interval variability was also observed in females. These findings underline that there are sex-specific differences concern the firing strategies based on task intensity.

Cell-Type-Dependent Recruitment Dynamics of FUS Protein at Laser-Induced DNA Damage Sites.

Increased signs of DNA damage have been associated to aging and neurodegenerative diseases. DNA damage repair mechanisms are tightly regulated and involve different pathways depending on cell types and proliferative vs. postmitotic states. Amongst them, fused in sarcoma (FUS) was reported to be involved in different pathways of single- and double-strand break repair, including an early recruitment to DNA damage. FUS is a ubiquitously expressed protein, but if mutated, leads to a more or less selective motor neurodegeneration, causing amyotrophic lateral sclerosis (ALS). Of note, ALS-causing mutation leads to impaired DNA damage repair. We thus asked whether FUS recruitment dynamics differ across different cell types putatively contributing to such cell-type-specific vulnerability. For this, we generated engineered human induced pluripotent stem cells carrying wild-type FUS-eGFP and analyzed different derivatives from these, combining a laser micro-irradiation technique and a workflow to analyze the real-time process of FUS at DNA damage sites. All cells showed FUS recruitment to DNA damage sites except for hiPSC, with only 70% of cells recruiting FUS. In-depth analysis of the kinetics of FUS recruitment at DNA damage sites revealed differences among cellular types in response to laser-irradiation-induced DNA damage. Our work suggests a cell-type-dependent recruitment behavior of FUS during the DNA damage response and repair procedure. The presented workflow might be a valuable tool for studying the proteins recruited at the DNA damage site in a real-time course.

Objective scanning-based fluorescence cross-correlation spectroscopy (Scan-FCCS) for studying the fusion dynamics of protein phase separation.

Protein phase separation plays a very important role in many biological processes and is closely related to the occurrence and development of some serious diseases. So far, the fluorescence imaging method and fluorescence correlation spectroscopy (FCS) have been frequently used to study the phase separation behavior of proteins. Due to the wide size distribution of protein condensates in phase separation from nano-scale to micro-scale in solution and living cells, it is difficult for the fluorescence imaging method and conventional FCS to fully reflect the real state of protein phase separation in the solution due to the low spatio-temporal resolution of the conventional fluorescence imaging method and the limited detection area of FCS. Here, we proposed a novel method for studying the protein phase separation process by objective scanning-based fluorescence cross-correlation spectroscopy (Scan-FCCS). In this study, CRDBP proteins were used as a model and respectively fused with fluorescent proteins (EGFP and mCherry). We first compared conventional FCS and Scan-FCS methods for characterizing the CRDBP protein phase separation behaviors and found that the reproducibility of Scan-FCS is significantly improved by the scanning mode. We studied the self-fusion process of mCherry-CRDBP and EGFP-CRDBP and observed that the phase change concentration of CRDBP was 25 nM and the fusion of mCherry-CRDBP and EGFP-CRDBP at 500 nM was completed within 70 min. We studied the effects of salt concentration and molecular crowding agents on the phase separation of CRDBP and found that salt can prevent the self-fusion of CRDBP and molecular crowding agents can improve the self-fusion of CRDBP. Furthermore, we found the recruitment behavior of CRDBP to β-catenin proteins and studied their recruitment dynamics. Compared to conventional FCS, Scan-FCCS can significantly improve the reproducibility of measurements due to the dramatic increase of detection zone, and more importantly, this method can provide information about self-fusion and recruitment dynamics in protein phase separation.

CRDBP Protein Phase Separation and Its Recruitment to β-Catenin Protein in a Single Living Cell.

The Coding Region Determinant-Binding Protein (CRDBP) is a carcinoembryonic protein, and it is overexpressed in various cancer cells in the form of granules. We speculated the formation of CRDBP granules possibly through liquid-liquid phase separation (LLPS) processes due to the existence of intrinsically disordered regions (IDRs) in CRDBP. So far, we did not know whether or how phase separation processes of CRDBP occur in single living cells due to the lack of in vivo methods for studying intracellular protein phase separation. Therefore, to develop an in situ method for studying protein phase separation in living cells is a very urgent task. In this work, we proposed an efficient method for studying phase separation behavior of CRDBP in a single living cell by combining in situ fluorescence correlation spectroscopy (FCS) and fluorescence cross-correlation spectroscopy (FCCS) with a fluorescence protein fusion technique. We first predicted and confirmed that CRDBP has phase separation in solution by conventional fluorescence imaging and FCS methods. And then, we in situ studied the phase separation behaviors of CRDBP in living cells and observed three states of CRDBP phase separation such as monomer state, cluster state, and granule state. We studied the effects of CRDBP truncated forms and its inhibitor on the CRDBP phase separation. Furthermore, we discovered the recruitment of CRDBP to β-catenin protein in living cells and investigated the effects of CRDBP structures and inhibitor on CRDBP recruitment behavior. This finding may help us to further understand the mechanism of CRDBP protein for regulating Wnt signaling pathway. Additionally, our results documented that FCS/FCCS is an efficient and alternative method for studying protein phase separation in situ in living cells.

Direct measurements of collagen fiber recruitment in the posterior pole of the eye

Collagen is the main load-bearing component of the peripapillary sclera (PPS) and lamina cribrosa (LC) in the eye. Whilst it has been shown that uncrimping and recruitment of the PPS and LC collagen fibers underlies the macro-scale nonlinear stiffening of both tissues with increased intraocular pressure (IOP), the uncrimping and recruitment as a function of local stretch have not been directly measured. This knowledge is crucial to understanding their functions in bearing loads and maintaining tissue integrity. In this project we measured local stretch-induced collagen fiber bundle uncrimping and recruitment curves of the PPS and LC. Thin coronal samples of PPS and LC of sheep eyes were mounted and stretched biaxially quasi-statically using a custom system. At each step, we imaged the PPS and LC with instant polarized light microscopy and quantified pixel-level (1.5 μm/pixel) collagen fiber orientations. We used digital image correlation to measure the local stretch and quantified collagen crimp by the circular standard deviation of fiber orientations, or waviness. Local stretch-recruitment curves of PPS and LC approximated sigmoid functions. PPS recruited more fibers than the LC at the low levels of stretch. At 10% stretch the curves crossed with 75% bundles recruited. The PPS had higher uncrimping rate and waviness remaining after recruitment than the LC: 0.9º vs. 0.6º and 3.1º vs. 2.7º. Altogether our findings support describing fiber recruitment of both PPS and LC with sigmoid curves, with the PPS recruiting faster and at lower stretch than the LC, consistent with a stiffer tissue. Statement of significancePeripapillary sclera (PPS) and lamina cribrosa (LC) collagen recruitment behaviors are central to the nonlinear mechanical behavior of the posterior pole of the eye. How PPS and LC collagen fibers recruit under stretch is crucial to develop constitutive models of the tissues but remains unclear. We used image-based stretch testing to characterize PPS and LC collagen fiber bundle recruitment under local stretch. We found that fiber-level stretch-recruitment curves of PPS and LC approximated sigmoid functions. PPS recruited more fibers at a low stretch, but at 10% bundle stretch the two curves crossed with 75% bundles recruited. We also found that PPS and LC fibers had different uncrimping rates and non-zero waviness's when recruited.

P2X7 receptor inhibition of microglia attenuates repeated social defeat induced monocyte recruitment and anxiety-like behavior

P2X7 receptor inhibition of microglia attenuates repeated social defeat induced monocyte recruitment and anxiety-like behavior

Antagonism of the brain P2X7 ion channel attenuates repeated social defeat induced microglia reactivity, monocyte recruitment and anxiety-like behavior in male mice

Chronic stress is linked to increased anxiety. Repeated social defeat (RSD) in mice causes anxiety that is dependent on activated neurons, reactive microglia, and accumulation of monocytes in the brain. This response requires interactions between the immune system and central nervous system (CNS). Neuronal activation within threat appraisal regions is a key response to RSD, however, it is unclear how microglia become activated. One potential explanation is that microglia express a purinergic non-selective ligand gated adenosine-triphosphate (ATP) receptor 7 (P2X7). Activation of P2X7 promotes the release of chemokines and cytokines, and recruitment of monocytes to the brain. Thus, the purpose of this study was to determine if a novel P2X7 antagonist blocked neuronal and microglia interactions and the corresponding anxiety following RSD. Male mice were administered (i.p.) a P2X7 antagonist, JNJ-54471300, prior to each cycle of RSD. Fourteen hours after RSD, behavioral deficits including social avoidance and anxiety-like were determined. Moreover, several immune parameters were assessed. RSD caused neuronal activation in stress-responsive regions, monocyte production and release, splenomegaly, and social avoidance. These parameters were unaffected by P2X7 antagonism. RSD-associated proportional area of Iba-1+ microglia, monocyte accumulation in the brain, IL-1β mRNA expression in enriched myeloid cells, plasma IL-6, and anxiety-like behavior were ameliorated by P2X7 antagonism. Gene expression analysis in the hippocampus and amygdala showed regional specific responses to RSD and some were reversed with P2X7 antagonism. Overall, blocking P2X7 activation attenuated RSD-induced microglia reactivity with corresponding reduction in neuroinflammation, monocyte accumulation, and anxiety-like behavior in male mice.

Regional recruitment and differential behavior of motor units during postural control in older adults.

Aging is associated with neuromuscular system changes that may have implications for the recruitment and firing behaviors of motor units (MUs). In previous studies, we observed that young adults recruit subpopulations of triceps surae MUs during tasks that involved leaning in five directions: common units that were active during different leaning directions and unique units that were active in only one leaning direction. Furthermore, the MU subpopulation firing behaviors [average firing rate (AFR), coefficient of variation (CoVISI), and intermittent firing] modulated with leaning direction. The purpose of this study was to examine whether older adults exhibited this regional recruitment of MUs and firing behaviors. Seventeen older adults (aged 74.8 ± 5.3 yr) stood on a force platform and maintained their center of pressure leaning in five directions. High-density surface electromyography recordings from the triceps surae were decomposed into single MU action potentials. A MU tracking analysis identified groups of MUs as being common or unique across the leaning directions. Although leaning in different directions did not affect the AFR and CoVISI of common units (P > 0.05), the unique units responded to the leaning directions by increasing AFR and CoVISI, albeit modestly (F = 18.51, P < 0.001). The unique units increased their intermittency with forward leaning (F = 9.22, P = 0.003). The mediolateral barycenter positions of MU activity in both subpopulations were found in similar locations for all leaning directions (P > 0.05). These neuromuscular changes may contribute to the reduced balance performance seen in older adults.NEW & NOTEWORTHY In this study, we observed differences in motor unit recruitment and firing behaviors of distinct subpopulations of motor units in the older adult triceps surae muscle from those observed in the young adult. Our results suggest that the older adult central nervous system may partially lose the ability to regionally recruit and differentially control motor units. This finding may be an underlying cause of balance difficulties in older adults during directionally challenging leaning tasks.

Skill demand and labour market concentration: evidence from Italian vacancies

PurposeThe authors provide a novel interpretation of the relationship between skill demand and labour market concentration based on the training rationale.Design/methodology/approachThe authors use a novel data set on Italian online job vacancies during 2013–2018 to analyse the relationship between labour market concentration and employers' skill demand. The authors construct measures of market concentration and skill intensity in the local labour market. The authors regress the measures of skill demand on market concentration, controlling for sector, occupations and other features of the labour market. The authors also use the Hausman–Nevo instrument for market concentration.FindingsThe authors show that employers in a highly concentrated labour market demand competencies associated with the ability of workers to learn faster (e.g. social skills) rather than actual knowledge. They also require less experience but higher education. These results are consistent with the hypothesis that employers in more concentrated labour markets are more prone to train their employees. Instead of looking for workers who already have job-specific skills, they look for workers who can acquire them faster and efficiently. The authors provide a theoretical framework within which to analyse these aspects as well as providing a test for the relevant hypotheses.Practical implicationsIn addition to cross-countries differences in labour market regulations, the authors' findings suggest that policy authorities should consider the local labour market structure when studying workforce development programmes aimed at bridging the skill gap of displaced workers. Moreover, the authors show that market concentration can have relevant implications for human resource (HR) managers by affecting their recruitment behaviour through the demand for skills. In fact, concentrated markets tend to favour firms' collusion and anti-competitive behaviour that could strongly affect HR management practices.Originality/valueThe authors' paper innovates on the literature in a number of ways. First, the authors provide evidence of local labour market concentration in Italy. Second, the authors provide evidence of skill demand at the local level using a detailed skill taxonomy that goes beyond the classical distinction between high and low skills. Third, and most importantly, the authors provide evidence of the relationship between skill demand and labour market concentration. By analysing detailed skills and competencies, the authors take one step beyond understanding the features of labour demand in monopsonistic markets.

The contribution of matrix metalloproteinases and their inhibitors to the development, progression, and rupture of abdominal aortic aneurysms.

Abdominal aortic aneurysms (AAAs) account for up to 8% of deaths in men aged 65 years and over and 2.2% of women. Patients with AAAs often have atherosclerosis, and intimal atherosclerosis is generally present in AAAs. Accordingly, AAAs are considered a form of atherosclerosis and are frequently referred to as atherosclerotic aneurysms. Pathological observations advocate inflammatory cell infiltration alongside adverse extracellular matrix degradation as key contributing factors to the formation of human atherosclerotic AAAs. Therefore, macrophage production of proteolytic enzymes is deemed responsible for the damaging loss of ECM proteins, especially elastin and fibrillar collagens, which characterise AAA progression and rupture. Matrix metalloproteinases (MMPs) and their regulation by tissue inhibitors metalloproteinases (TIMPs) can orchestrate not only ECM remodelling, but also moderate the proliferation, migration, and apoptosis of resident aortic cells, alongside the recruitment and subsequent behaviour of inflammatory cells. Accordingly, MMPs are thought to play a central regulatory role in the development, progression, and eventual rupture of abdominal aortic aneurysms (AAAs). Together, clinical and animal studies have shed light on the complex and often diverse effects MMPs and TIMPs impart during the development of AAAs. This dichotomy is underlined from evidence utilising broad-spectrum MMP inhibition in animal models and clinical trials which have failed to provide consistent protection from AAA progression, although more encouraging results have been observed through deployment of selective inhibitors. This review provides a summary of the supporting evidence connecting the contribution of individual MMPs to AAA development, progression, and eventual rupture. Topics discussed include structural, functional, and cell-specific diversity of MMP members; evidence from animal models of AAA and comparisons with findings in humans; the dual role of MMPs and the requirement to selectively target individual MMPs; and the advances in identifying aberrant MMP activity. As evidenced, our developing understanding of the multifaceted roles individual MMPs perform during the progression and rupture of AAAs, should motivate clinical trials assessing the therapeutic potential of selective MMP inhibitors, which could restrict AAA-related morbidity and mortality worldwide.

C-Myc-induced hypersialylation of small cell lung cancer facilitates pro-tumoral phenotypes of macrophages

Immunosuppressive myeloid cell populations have been documented in small cell lung cancer (SCLC) subtypes, playing a key role in remolding the tumor microenvironment (TME). However, the cancer-associated transcriptional features of monocytes and tumor-associated macrophages (TAMs) in SCLC remain poorly understood. Herein, we analyzed the molecular features and functions of monocyte/macrophage subsets aiming to inhibit monocyte recruitment and pro-tumor behavior of macrophages. We observe that NEUROD1-high SCLC subtype (SCLC-N) exhibits subtype-specific hypersialylation induced by the unique target c-Myc (MYC) of NEUROD1. The hypersialylation can alter macrophage phenotypes and pro-tumor behavior by regulating the expression of the immune-inhibiting lectin receptors on monocyte-derived macrophages (MDMs) in SCLC-N. Inhibiting the aberrant sialic acid metabolic pathways in SCLC can significantly enhance the phagocytosis of macrophages. This study provides a comprehensive overview of the cancer-specific immune signature of monocytes and macrophages and reveals tumor-associated biomarkers as potential therapeutic targets for SCLC.

How much does an employer's attractiveness matter to youth employment? Evidence from a developing country

PurposeDrawing on the contemporary literature and the theory of employer attractiveness, the authors aimed to examine key antecedents and consequences of employer attractiveness by proposing functional hypotheses and relationships between some endogenous variables.Design/methodology/approachUsing the quota-cum-purposive sampling method, the unit of analysis selected for this study was millennials aged 18–35 years and working in the hospitality, travel, tourism and leisure (HTTL) sectors for the last two years. A total of 218 responses were collected in three months (June–August 2022). The data were analysed using partial least squares structural equation modelling (PLS-SEM).FindingsFor young employees, company recruitment behaviour, company image and source credibility are significantly and directly related to company attractiveness. The relationship between company image and employee word of mouth (WOM) was significantly positive. Company recruitment behaviour was found to significantly influence employee commitment. Company attractiveness was found to be directly related to young employees' WOM about the company and commitment to it.Originality/valueThe study establishes the significance of company attractiveness because a company's success largely depends on the company's ability to attract and retain a talented and skilled workforce. Moreover, the present study provides much-needed insights to policymakers and regulators that can help the policymakers define and implement favourable policies to promote and protect the country's job market and offer directions to youth employment.

A time-dependent Poisson-Gamma model for recruitment forecasting in multicenter studies.

Forecasting recruitments is a key component of the monitoring phase of multicenter studies. One of the most popular techniques in this field is the Poisson-Gamma recruitment model, a Bayesian technique built on a doubly stochastic Poisson process. This approach is based on the modeling of enrollments as a Poisson process where the recruitment rates are assumed to be constant over time and to follow a common Gamma prior distribution. However, the constant-rate assumption is a restrictive limitation that is rarely appropriate for applications in real studies. In this paper, we illustrate a flexible generalization of this methodology which allows the enrollment rates to vary over time by modeling them through B-splines. We show the suitability of this approach for a wide range of recruitment behaviors in a simulation study and by estimating the recruitment progression of the Canadian Co-infection Cohort.

Datamama, bringing pregnancy research into the future: design, development, and evaluation of a citizen science pregnancy mobile application

Background: Pregnancy mobile applications (apps) have grown in popularity over the past decade, with some being used to promote study recruitment or health behaviors. However, no app serves as an all-in-one solution for collecting general data for research purposes and providing women with useful and desirable features.Aim: To create and develop a Swiss pregnancy mobile app as an innovative means to collect research data and provide users with reliable information.Methods: Determining the key features of the app involved a review of the literature and assessment of popular apps in the Swiss AppStore. A team of engineers developed the app, which includes a pregnancy timeline, questionnaires for data collection, medical and psychological articles and a checklist with appointment reminders. The content was written and reviewed by healthcare providers considered experts in the topics adressed. The questionnaires are distributed based on the user’s gestational age, by a chatbot. The project was authorized by the ethics commission in the canton of Vaud. An online survey of ten questions, advertised on Datamama’s home screen, was conducted to assess the users’ use of the app (27.11- 19.12.2022).Results: A review of 84 articles and 25 popular apps showed the need for a comprehensive pregnancy app. The development of Datamama took 2 years and included the creation of 70 medical and psychological articles and 29 questionnaires covering 300 unique variables. Six months after the launch, there were 800 users with a 73% average participation rate in the questionnaires. Sixty-five women completed the survey, with 70.8% using the app once to multiple times per week. The primary reason for using the app was to help research by answering the questionnaires, followed by access to reliable medical information. The reason most frequently ranked first for using the app was to help research by answering the questionnaires (42/65, 67% of women rated it first), followed by access to reliable medical information (34/65, 54% women rated it second). Women rated the information as clear, understandable, and interesting with a trust rating in data handling at 98.5%. The average grade for recommending the app was 8/10, with suggestions for increasing the amount of medical content and tailoring it based on gestational age.Conclusion: Datamama is the first pregnancy app to address the needs of both patients and researchers. Initial feedback from users was positive, highlighting future challenges for success. Future work will consist in improving the app, validating the data and use it to answer specific pregnancy-related research questions.

Recruitment Behaviour in an African Meliponine Bee Species (hymenoptera, Apidae: Meliponini): Understanding Glandular Origin and Pheromonal Components

Meliponine bees are speculated to use a variety of communication mechanisms to effectively recruit workers of a colony to collect sufficient amounts of food to nourish the entire nest population. Mechanisms used to convey such information include thoracic vibrations and trophallaxis within the nest; footprint secretions and pheromone marks deposited in the field, or a combination of these signals and cues. There have been numerous discrepancies about the origin of trail pheromone production from the head, thorax, abdomen and leg regions of meliponine bees. Because the glandular origin of pheromone marks deposited by African meliponine bee’s species has not yet been investigated, we first confirmed if these species actually carry out scent marking and recruitment behaviour at visited food sources. Secondly, we tested if either nasonov or tarsal gland secretions elicited trail-following behaviour in newly recruited bees by means of chemical and electro-physiological analyses as well as with bio-assays testing both natural extracts and synthetic pheromone compounds from both glands. Significant differences were observed in the foraging patterns of the four bee species on collected resources (nectar, pollen and water) as the synthetic compound, (E)-β-farnesene was significantly as attractive to foragers of the four species when compared to the natural nasonov gland extract. Our results showed a significantly higher proportion of foragers from the four species been attracted to food resources baited with natural extracts from their own glands and recruited additional foragers to such baited food sites.&#x0D; Keywords: Meliponine bee species, recruitment behaviour, nasonov glands, tarsal glands

COVID-19 and labour market resilience: evidence from large-scale recruitment behaviour

ABSTRACT We construct a theoretical model to interpret the structural shock from the COVID-19 pandemic and the response of local labour market and industry specialization. The empirical study takes the large-scale online labour market of China to analyse firms’ hiring demand for 20 industries across 380 cities with monthly recruitment data from May 2017 to September 2020. Post-event quantitative analysis on job postings and employer demand highlighted that the pandemic resulted in an unemployment shock and industry- and city-level redistribution of the worker. China’s local job market resilience also revealed a regional imbalance, correlated with pandemic risk, city scale and industry structure.

Diseased and healthy murine local lung strains evaluated using digital image correlation

Tissue remodeling in pulmonary disease irreversibly alters lung functionality and impacts quality of life. Mechanical ventilation is amongst the few pulmonary interventions to aid respiration, but can be harmful or fatal, inducing excessive regional (i.e., local) lung strains. Previous studies have advanced understanding of diseased global-level lung response under ventilation, but do not adequately capture the critical local-level response. Here, we pair a custom-designed pressure–volume ventilator with new applications of digital image correlation, to directly assess regional strains in the fibrosis-induced ex-vivo mouse lung, analyzed via regions of interest. We discuss differences between diseased and healthy lung mechanics, such as distensibility, heterogeneity, anisotropy, alveolar recruitment, and rate dependencies. Notably, we compare local and global compliance between diseased and healthy states by assessing the evolution of pressure-strain and pressure–volume curves resulting from various ventilation volumes and rates. We find fibrotic lungs are less-distensible, with altered recruitment behaviors and regional strains, and exhibit disparate behaviors between local and global compliance. Moreover, these diseased characteristics show volume-dependence and rate trends. Ultimately, we demonstrate how fibrotic lungs may be particularly susceptible to damage when contrasted to the strain patterns of healthy counterparts, helping to advance understanding of how ventilator induced lung injury develops.

Salivary gland substances of the arboreal termite Nasutitermes corniger induce worker aggregation and gnawing of food substrate

In social insects, collective behavior is regulated by substances secreted by various glands of different members of society. In this study, we investigate whether salivary glands of the arboreal termite Nasutitermes corniger (Motschulsky) (Isoptera: Termitidae) contain substances that regulate the intensity of foraging behavior. Foraging arenas of N. corniger nests maintained under laboratory conditions received the addition of two filter paper substrates, one impregnated with salivary gland extract from third-instar small workers (SW3) (treatment) and the other impregnated with distilled water (control). A similar experiment was conducted using salivary gland extract from fourth-instar large workers (LW4). Occurrences of initial exploration, mass recruitment, and substrate gnawing behaviors, as well as numbers of recruited and gnawing workers, were recorded. There was a higher rate of mass recruitment to treated substrates than to the control (SW3: 80 vs. 25%; LW4: 90 vs. 25%). Gnawing behavior also occurred at higher rates on treated substrates (SW3: 95 vs. 35%; LW4: 100 vs. 45%). The number of workers recruited to and gnawing on treated substrate was significantly higher than the number of workers recruited to and gnawing on control substrate. The higher rates of worker recruitment, as well as the higher numbers of recruited and gnawing workers, show that salivary glands of last-instar workers contain substances with arresting and/or phagostimulating pheromonal actions or substances that release compounds with these properties.

Fertility Control for Wildlife: A European Perspective.

Trends of human population growth and landscape development in Europe show that wildlife impacts are escalating. Lethal methods, traditionally employed to mitigate these impacts, are often ineffective, environmentally hazardous and face increasing public opposition. Fertility control is advocated as a humane tool to mitigate these impacts. This review describes mammalian and avian wildlife contraceptives' effect on reproduction of individuals and populations, delivery methods, potential costs and feasibility of using fertility control in European contexts. These contexts include small, isolated wildlife populations and situations in which lethal control is either illegal or socially unacceptable, such as urban settings, national parks and areas where rewilding occurs. The review highlights knowledge gaps, such as impact of fertility control on recruitment, social and spatial behaviour and on target and non-target species, provides a decision framework to assist decisions about the potential use of wildlife fertility control, and suggests eight reasons for Europe to invest in this area. Although developing and registering contraceptives in Europe will have substantial costs, these are relatively small when compared to wildlife's economic and environmental impact. Developing safe and effective contraceptives will be essential if European countries want to meet public demand for methods to promote human-wildlife coexistence.