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Grooming among nonhuman primates is widespread and may represent an important service commodity that is exchanged within a biological marketplace. In this study, using focal animal sampling methods, we recorded grooming relationships among 12 adult females in a free-ranging group of Tibetan macaques (Macaca thibetana) at Huangshan, China, to determine the influence of rank and kinship on grooming relationships, and whether females act as reciprocal traders (exchange grooming received for grooming given) or interchange traders (interchange grooming for social tolerance or other commodities). The results showed that: (1) grooming given was positively correlated with grooming received; (2) kinship did not exert a significant influence on grooming reciprocity; and (3) grooming reciprocity occurred principally between individuals of adjacent rank; however, when females of different rank groomed, females tended to groom up the hierarchy (lower ranking individuals groomed higher ranking individuals more than vice versa). Our results support the contention that both grooming reciprocity and the interchange of grooming for tolerance represent important social tactics used by female Tibetan macaques.

We improved the piezoelectric property of poly(vinylidene fluoride) (PVDF) by employing graphene. The reduced graphene oxide (rGO)–PVDF nanocomposites were prepared by a solution casting method and the rGO contents ranged from 0.0 wt% to 0.2 wt%. To induce the piezoelectric β-phase crystal structure, the nanocomposite films were drawn in a ratio of 4–5 and polarized by a step-wise poling method. To evaluate the piezoelectric property, the output voltages of the rGO–PVDF nanocomposite films were measured through extensive experimental vibration tests. The experimental results show that the rGO–PVDF nanocomposite film with 0.05 wt% rGO loading possesses the highest output voltage compared with other loadings, which is around 293% of that of the pure PVDF film. Moreover, it can be found that with the increase of the rGO content from 0 wt% to 0.2 wt%, the output voltage tends to have a peak at 0.05 wt%. The main reason for this phenomenon is that a more β-crystalline phase can be formed at those rGO loadings, as confirmed by XRD and FT-IR spectrum analyses.

Primate tourism is a growing trend in habitat countries, but few assessments of its impact on primate groups are available. We compare infant mortality in a group of Tibetan macaques (Macaca thibetana) 6 yr before the government translocated the group and subsequently used them for tourism , 12 yr during management for tourism (1992)(1993)(1994)(1995)(1996)(1997)(1998)(1999)(2000)(2001)(2002) 2004), and 1 yr when management was temporarily suspended (2003). We also compare aggression rates among adults before and during management, and test several hypotheses about specific factors (numbers of tourists, degree of range restriction, demographic changes, changes in α-males) that may have harmed infants. Infant mortality was significantly higher during management than before, but it was similar before management vs. during its suspension. After management began, serious attacks on infants occurred shortly before they died, and many infant corpses had bite wounds. Typically, infants sustained wounds after aggression broke out among adults in the provisioning area used for tourist viewing. Adult aggression rates in the provisioning area correlated positively with infant mortality over time. Range restriction accounted for 54.5% of the variation in infant mortality, and was more closely associated with both mortality and aggression than any other specific factor examined. We hypothesize that range restriction led to increased infant mortality by raising aggression levels in the provisioning area. We conclude that infant mortality is useful as an indicator of the impact of tourism on primate groups, and that range restriction is an inappropriate tourism management practice.

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Recent studies highlight that the gut mycobiota play essential roles in mammalian metabolic and immune systems, but to date we lack information on the forces that naturally shape the gut mycobiota of wild primates. To investigate the contributions of host and environmental factors in the taxonomic variation of the gut mycobiota, we examined the effects of age, sex, and season on the fecal mycobiota in wild-living Tibetan macaques (Macaca thibetana). Using next generation sequencing and a longitudinal set of fecal samples collected over 1 year, we identified a set of core fungal taxa present in the Tibetan macaque's fecal samples. The predominant genera Aspergillus and Penicillium, which promote the digestion of cellulose and hemicellulose in herbivorous mammals, were detected in this study. Similar to humans, we found age and sex effects on the macaques' fecal mycobiota. We also found that both fecal fungal composition and diversity (alpha and beta diversity) varied significantly by season. In particular, the Penicillium enriched mycobiota in summer samples may aid in the digestion of cellulose and hemicellulose present in mature leaves. The high alpha diversity detected in Tibetan macaques' winter fecal samples may facilitate a diet rich in fiber ingested during this season. We propose that the gut mycobiota play an important role in the macaques' ability to adapt to seasonal fluctuations in food availability and nutrient content.

Many hybrid proline-rich protein (HyPRP) genes respond to biotic and abiotic stresses in plants, but little is known about their roles other than as putative cell-wall structural proteins. A HyPRP1 gene encodes a protein with proline-rich domain, and an eight-cysteine motif was identified from our previous microarray experiments on drought-tolerant tomato. In this study, the expression of the HyPRP1 gene in tomato was suppressed under various abiotic stresses, such as drought, high salinity, cold, heat, and oxidative stress. Transgenic functional analysis showed no obvious changes in phenotypes, but enhanced tolerance to various abiotic stresses (e.g., oxidative stress, dehydration, and salinity) was observed in RNAi transgenic plants. Interestingly, several SO2 detoxification-related enzymes, including sulfite oxidase, ferredoxins (Fds), and methionine sulfoxide reductase A (Msr A), were revealed in HyPRP1-interacting proteins identified by Yeast Two-Hybrid screening. More sulfates and transcripts of Msr A and Fds were accumulated in HyPRP1 knockdown lines when wild-type plants were exposed to SO2 gas. Our findings illustrate that the tomato HyPRP1 is a negative regulator of salt and oxidative stresses and is probably involved in sulfite metabolism.