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Sperm production represents a costly reproductive investment by males. High reproductive competition within the female reproductive tract may select for higher sperm counts or quality resulting in selection for larger testes size. In species where females mate multiply or have more offspring per litter (litter size), or more litters per year (litter rate), male reproductive competition may select for larger relative testes size (i.e., scaled by body mass). Given that different mating systems vary in the alternative forms of reproductive investment available to males, sperm production levels may vary with social system. Here, we examined the relationship between testes size and mating systems, litter size, and litter rate while considering male lifespan and investment in paternal care in 224 terrestrial mammalian species in 15 orders. Relative testes size was larger in species where females mated with multiple males. Furthermore, in species with multiple mating females, species with higher litter rates had larger testes compared to species with fewer litters per year. In contrast, in monogamous species, species that had multiple litters per year had smaller relative testes sizes compared to species with fewer litters per year. Neither longevity nor paternal care influenced testes size. Our results elucidate the effect of female reproductive strategies on relative testes size is nuanced and varies between mating systems. Our findings suggest that the interplay between male reproductive investment and female reproductive investment may be different within similar social mating systems. [ABSTRACT FROM AUTHOR]

The bushmeat trade, or the trade in wild animals for meat, is a primary threat to wildlife and ecosystems in Sulawesi, Indonesia. Hunting for trade and consumption can hasten the local extirpation of vulnerable species, such as fruit bats and the protected babirusa and Sulawesi crested black macaque. This study provides a much‐needed step in understanding the bushmeat trade by describing longitudinal trends in the amount of bushmeat (animal carcasses) observed for sale in markets in North Sulawesi, a particularly biodiversity‐rich area. Surveys were conducted in 10 markets in 2011, 2015, 2018 and 2019. At each market, total counts of all taxa for sale were noted, and encounter rates per market sample were derived to account for variable sampling effort across years and markets. Generalized Linear Mixed Models were used to compare encounter rates across years, months and markets. Our results show that although animal carcasses are still sold in high numbers, there has been an overall decrease between 2011 and 2019, particularly between 2011 and 2018 (encounter rate fell by 99%). However, bats, rats and Sulawesi warty pigs were still present at high levels, indicating a persistent demand for bushmeat in North Sulawesi. The encounter rate of protected taxa for sale was low, but steady throughout the study period. We identified which markets sold the greatest amount of bushmeat to inform future conservation actions and management. Based on our results, the persistent demand for bushmeat in the region, and the continued presence of protected taxa in the markets, we recommend further research to establish the sustainability of the bushmeat trade at its current rate. [ABSTRACT FROM AUTHOR]

Background: Bibliometric and Altmetric analyses provide different perspectives regarding research impact. This study aimed to determine whether Altmetric score was associated with citation rate independent of established bibliometrics. Methods: Citations related to a previous cohort of 100 most cited articles in surgery were collected and a 3-year interval citation gain calculated. Citation count, citation rate index, Altmetric score, 5-year impact factor, and Oxford Centre for Evidence-Based Medicine levels were used to estimate citation rate prospect. Results: The median interval citation gain was 161 (i.q.r. 83-281); 74 and 62 articles had an increase in citation rate index (median increase 2.8 (i.q.r. -0.1 to 7.7)) and Altmetric score (median increase 3 (0-4)) respectively. Receiver operating characteristic (ROC) curve analysis revealed that citation rate index (area under the curve (AUC) 0.86, 95 per cent c.i. 0.79 to 0.93; P < 0.001) and Altmetric score (AUC 0.65, 0.55 to 0.76; P = 0.008) were associated with higher interval citation gain. An Altmetric score critical threshold of 2 or more was associated with a better interval citation gain when dichotomized at the interval citation gain median (odds ratio (OR) 4.94, 95 per cent c.i. 1.99 to 12.26; P = 0.001) or upper quartile (OR 4.13, 1.60 to 10.66; P = 0.003). Multivariable analysis revealed only citation rate index to be independently associated with interval citation gain when dichotomized at the median (OR 18.22, 6.70 to 49.55; P < 0.001) or upper quartile (OR 19.30,4.23 to 88.15; P < 0.001). Conclusion: Citation rate index and Altmetric score appear to be important predictors of interval citation gain, and better at predicting future citations than the historical and established impact factor and Oxford Centre for Evidence-Based Medicine quality descriptors. [ABSTRACT FROM AUTHOR]

Body size impacts nearly all aspects of an animal's life and can be subject to considerable variation in response to differences in climate and resource availability. We studied the impact of temperature and resource availability on arid‐living Cape ground squirrels (Xerus inauris), relative to body size and degree of sexual dimorphism, over three locations differing in annual rainfall and temperature to test Bergmann's rule, the resource rule and Rensch's rule. We found that squirrels were the largest where resources were the highest and temperatures were the lowest but squirrels were similar in mass where resources were medium or low and temperatures medium and highest, partially supporting Bergmann's rule and the resource rule. Hind‐feet were the largest where resources were medium and temperatures were medium and similarly small in low and high resource and high‐ and low‐temperature areas. The degree of sexual dimorphism of hind‐foot and mass was constant no matter the resource abundance or temperature, suggesting no impact of resource availability or temperature on the degree of sexual dimorphism, contradicting Rensch's rule. Our findings suggest that, while resource availability and temperature may have an impact on body size, other mechanisms may be important in limiting both body size and degree of sexual dimorphism in this species. [ABSTRACT FROM AUTHOR]

The exponential growth of human population and infrastructure is significantly reducing the amount of ecological resources available for wild animals. We analyzed the effect of human activity on Barbary macaques Macaca sylvanus, an endangered species restricted to the fragmented forests of Morocco and Algeria, using location data from five social groups inhabiting Ifrane National Park, Morocco. We used a resource selection function to explore the effects of anthropogenic disturbance on macaque habitat selection, using nine natural, social, and anthropogenic disturbance variables as predictors. Forest cover, home range overlap, herding route proximity, and road proximity were all significant predictors of habitat use. Macaques avoided areas used by local shepherds, to reduce the risk of attack by shepherds' dogs, but approached roads to increase the chances of provisioning by tourists. However, herding route and road use varied seasonally in line with levels of human use, suggesting that macaques may be navigating their environment strategically (in space and time) to balance food acquisition and risk avoidance. The results of this study highlight the importance of assessing human impact on habitat selection in both space and time. Our data on seasonal variations in macaques' use of roads can help prevent road injuries, a major source of mortality for provisioned macaques, by focusing management efforts by national park workers in time and space. Furthermore, understanding when and where macaques seek provisioning from tourists can help combat provisioning, which negatively impacts macaque health, behavior, and susceptibility to poaching. [ABSTRACT FROM AUTHOR]

Presents a study that investigated magneto-transport and cyclotron resonance of two-dimensional electron gas in silicon under a magnetic field. Details of the experiments; Results and discussion.

Presents a study which examined the growth of indium antimonide on gallium arsenide by molecular beam epitaxy (MBE). Experimental details; Discussion of the MBE growth of indium antimony; Conclusions.

Pregnancy and lactation are reproductive phases that require large amounts of energy. Females in the reproductive period need good quality and quantity of food to provide nutrition for the fetus, milk production and child care. The mother will adapt to changes in behavior patterns and food type to meet these needs. The influence of parity and environmental conditions can affect the behavior patterns of females. During pregnancy, the Macaca nigra is known to have different proportion of activities in each period, while the behavior during the lactation phase in each mester is unknown. Therefore, this study aimed to analyze the behavior patterns in each mester and the food selection of Macaca nigra during the pregnancy and lactation phases, as well as the influence of female parity and environmental toward the behavior patterns. There were 39 females Macaca nigra observed from two groups from August 2018 to July 2019. An instantaneous focal sampling method was performed to observe females’ daily activities, continuous focal sampling to monitor food types and a selectivity index to analyze food type preferences. The results showed that the female Macaca nigra pattern was influenced by the reproductive phase, female parity and environmental conditions. Females at the end of the pregnancy and lactation phases had a high proportion of feeding and eat more arthropods. Primiparous females mostly performed resting activities. Food preference was influenced by reproductive factors and food availability. The choice of fruit could be affected by fruit availability, and their favorite food was D. mangiferum and Euginia sp.

Predator harassment is an anti-predator behaviour that may increase an individual's risk of predation, as individuals approach, threaten and harass a potential predator, yet this behaviour is still not well understood. The Cape ground squirrel (Xerus inauris) is a highly social facultative cooperative breeder from southern Africa that harasses several species of venomous snakes. We examined whether harassment was part of alloparental care by comparing harassment behaviours among different age and sex classes in Cape ground squirrel social groups. We also assessed how individuals adjusted their behaviour dependent on levels of risk by examining the Cape ground squirrel's harassment behaviour among non-venomous, and two species of venomous snakes. We found adult females with emerged juvenile offspring took the most risk, harassing for longer durations and at higher intensities than other group members, suggesting that snake harassment was a maternal behaviour. Females with juvenile offspring only harassed the highest risk elapid snake but increased vigilance and inspection with increasing snake risk suggesting that the Cape ground squirrel can discriminate between different types of snake predators. [ABSTRACT FROM AUTHOR]

Introducing coating layers on magnesium substrates for added corrosion protection has been one of the most popular methods to improve the relatively poor corrosion resistance of Mg biomaterials. Investigations on coating systems for Mg biomaterials to date have predominantly focused on smooth, polished surface topographies. Given that the corrosion resistance of biodegradable Mg increases with increasing surface roughness, the potential effectiveness of currently adopted coating methods could also be affected by changes in Mg surface topography. In this study, a biomimetic calcium phosphate (CaP) coating technique was employed to study the corrosion resistance of cast, pure Mg samples with high surface roughness of Ra = 9·12 μm. The effectiveness of the coating technique on rough samples was tested in vitro and compared with that of the raw polished pure Mg samples. It was found that while the biomimetic coating technique provided excellent corrosion protection to the smooth polished samples, the improvement in corrosion behaviour of rough cast samples was not as significant. With the findings in this study, it is suggested that future studies on Mg coatings should be performed on rough as well as smooth surfaces for a complete evaluation on the effectiveness of the coating system. [ABSTRACT FROM AUTHOR]

Biomimetic calcium phosphate coatings have been studied to improve the corrosion resistance of biodegradable magnesium alloys. The corrosion resistance of these coatings is often limited by defects during creation. A method for improving the corrosion response of these coatings is therefore needed if biomimetic coatings are to be used for corrosion protection. In this study, a calcium hydroxide underlayer was applied to improve the properties of these biomimetic coatings. The in vitro corrosion response was studied using hydrogen evolution and electrochemical techniques. It was found that the calcium hydroxide layer increased the corrosion resistance of the coatings. The coatings created had fewer defects than the unmodified biomimetic coatings. Over time, the calcium hydroxide layer also prevented the defects in the coating from growing, leading to longer lasting protection. The results of this study suggest that calcium hydroxide coatings can significantly improve the corrosion protection of a biomimetic coating. [ABSTRACT FROM AUTHOR]

Each year in the United States, approximately 80,000 women are diagnosed with gynecologic cancers. Cancer in the female reproductive organs affects sexual functioning in an estimated 50% of women with these cancers. Sexuality issues may persist for more than 10 years after diagnosis, making awareness of these issues an important factor in efforts to improve the quality of life for these women. This article reviews how sexuality is affected and provides recommendations for effective communication, assessment, and management strategies related to sexual dysfunction in gynecologic cancer survivors. [ABSTRACT FROM AUTHOR]

The reproductive output of iteroparous females is influenced by parity and resource availability. To gain a better understanding of the reproductive decisions made when animals are faced with potential trade-offs between current and future reproduction; we investigated the relationship of parity and resources availability on reproductive intervals and success by comparing the performance of primiparous and multiparous female Cape ground squirrels Xerus inauris from two study sites that differed in resource availability. Our study included the correlation of reproductive behavioral data with fecal hormonal information to establish a normative endocrine profile for pregnancy and lactation. Parity had a major influence on juvenile emergence with multiparous females having more juveniles emerge successfully. Resource availability did not influence reproductive output, either because of an interaction among multiple resource components including quantity, predictability and length of time those resources were available or because other factors (such as predation or parasitism) have a greater impact on reproductive success. [ABSTRACT FROM AUTHOR]

The few studies that have looked at genital allometry in mammals have typically shown a positively allometric relationship with body size and high coefficients of variation. Cryptic female choice, sexual conflict or sperm competition are mechanisms underlying genital evolution and as these are not mutually exclusive, they are often difficult to disentangle. In addition, these mechanisms are affected by both male and female social structure and/or mating strategies and, as such, pre- and post-copulatory behaviours have been shown to alter selection on genitalia. We examined genital traits and allometry in a polygynandrous and social ground squirrel Xerus inauris. We found that male testes are positively allometric and account for 1.5% of their body weight, one of the highest percentages known for sciurids. The penis, at 42.4% of head/body length, was isometric while the female reproductive tract, 22.4% head/body length, demonstrated no such relationship. Based on the allometric relationships of both males and females presented here, in conjunction with high levels of competition for females and lack of male aggression and territoriality, we suggest that sperm competition is the most likely mechanism for the evolution of the extremely large genitalia in this species. [ABSTRACT FROM AUTHOR]

Monitoring vital signs and locations of certain classes of ambulatory patients can be useful in overcrowded emergency departments and at disaster scenes, both on-site and during transportation. To be useful, such monitoring needs to be portable and low cost, and have minimal adverse impact on emergency personnel, e.g., by not raising an excessive number of alarms. The SMART (Scalable Medical Alert Response Technology) system integrates wireless patient monitoring (ECG, SpO(2)), geo-positioning, signal processing, targeted alerting, and a wireless interface for caregivers. A prototype implementation of SMART was piloted in the waiting area of an emergency department and evaluated with 145 post-triage patients. System deployment aspects were also evaluated during a small-scale disaster-drill exercise. [ABSTRACT FROM AUTHOR]

Studies of population dynamics, movement patterns and animal behavior usually require identification of individuals. We evaluated the reliability of using whisker spot patterns to noninvasively identify individual polar bears Ursus maritimus. We obtained the locations of polar bear whisker spots from photographs taken in western Hudson Bay, tested the independence of spot locations, estimated the complexity of each spot pattern in terms of information and determined whether each whisker spot pattern was reliable from its information content. Of the 50 whisker spot patterns analyzed, 98% contained enough information to be reliable, and this result varied little among observers. Photographs taken <50 m from polar bears were most useful. Our results suggest that individual identification of polar bears in the field based on whisker spot pattern variations is reliable. Researchers studying polar bear behavior or estimating population parameters can benefit from this method if proximity to the bears is feasible. [ABSTRACT FROM AUTHOR]

The Cape ground squirrel Xerus inauris is unusual among social mammals as it exhibits a low reproductive skew, being a facultative plural breeder with not all females breeding within a group. We investigated pituitary function to assess whether there was reproductive inhibition at the level of the pituitary and potentially the hypothalamus in breeding and non-breeding female Cape ground squirrels. We did so during the summer and winter periods by measuring luteinizing hormone (LH) responses to single doses of 2 g exogenous gonadotropin-releasing hormone (GnRH) and physiological saline administered to 42 females from 11 colonies. Basal LH concentrations of females increased in response to the GnRH challenge. Basal plasma LH concentrations were greater during winter, when most oestrus events are observed. However, we found no differences in plasma LH concentrations between breeding and non-breeding females. We showed that the anterior pituitary of non-breeding female ground squirrels is no less sensitive to exogenously administered GnRH than that of breeding females. We therefore concluded that the pituitary is no more active in breeding than non-breeding females. The lack of differentiation in response to GnRH suggests that either non-breeding females have ovaries that are less sensitive to LH or that they refrain from sexual activity with males through an alternative mechanism of self-restraint. [ABSTRACT FROM AUTHOR]