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1.
iScience ; 27(4): 109424, 2024 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-38510146

RESUMO

To meet the requirements of fast response and simple process of deep ultraviolet (UV) pulsed laser detector, table salt (TS) was used as laser detection material in combination with a variable resistor to achieve single-pulse laser detection. Under the irradiation of a KrF excimer laser, the laser-induced voltage (LIV) of TS was influenced by the dynamic process of laser-induced plasma, and the whole process was well fitted with the sum of the three exponential functions. As the applied bias voltage (Vb) and incident laser energy (Ein) increased, the LIV amplitude (Vp) increased and the response time decreased. When the variable resistor (R) was reduced to 14.7 Ω, the response time of LIV decreased from ∼300 µs to ∼20 ns, which is the same as the duration of laser pulse. This research provided a simple, low-cost, and fast method for the detection of UV single-pulse laser based on the laser-TS interaction.

2.
Heliyon ; 9(11): e21195, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37954347

RESUMO

In this work, we proposed a laser-induced current (LIC) method to investigate the grain-size dependence of the plasma of table sugar induced by a nanosecond (ns) pulsed ultraviolet laser in the size range of <180 µm->550 µm and achieve the lower power consumption in measurement. Under multiple laser irradiations and an external electric field (Vb) of 200 V, the LIC variation's (ΔIp) standard deviation and variance were 0.53 nA and 0.05 nA, respectively, indicating the relatively small systematic error during the testing process. The Vb causes a decrease in the possibility of electron-ion complexation and accelerates the separation, resulting in an increase in ΔIp with Vb. With increasing grain size (diameter D) of table sugar, ΔI demonstrate a valley-like behaviour and 250-380 µm is the critical range Dc where ΔI is very weak and considerably depends on the Vb with the slope of 0.031 nA/V. At D > 550 µm and Vb = 5 V, ΔI intensities monotonically rise by 30 % when D surpasses Dc. In this instance, the energy was the main contributor to the LIC signal during plasma generation and expansion. While D is less than Dc, ΔIp increases by 27 % at D ≤ 180 µm and Vb = 5 V. The yield stress is the main reason for the formation of plasma with high temperature and density in this situation because the sugar behaves like an elastic solid. The reason for such a LIC variation trend was discussed, which can be explained by considering the morphological, thermal and mechanical properties competing with each other. The present result suggests that the LIC method enables non-contact characterisation of sugar particle size at low-power consumption.

3.
Nutrients ; 15(19)2023 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-37836514

RESUMO

Constipation is currently one of the most common gastrointestinal disorders, and its causes are diverse. Multi-strain probiotics are often considered a more effective treatment than single-strain probiotics. In this study, a constipation model was constructed using loperamide hydrochloride to evaluate the ability of a multi-strain probiotic combination of four different ratios of Bifidobacterium and Lactobacillus to regulate intestinal flora, relieve constipation, and explore the initial mechanism in mice. After four weeks of probiotic intervention, BM1, BM2, and PB2 effectively relieved constipation; however, the pathways involved were different. The Bifidobacteria-dominated formulations BM1 and BM2 mainly changed the composition and structure of the intestinal flora and significantly decreased the relative abundance of Tyzzerella, Enterorhabdus, Faecalibaculum, Gordonibacter, and Mucispirillum in stool; increased the relative abundance of Parabacteroides and the content of short-chain fatty acids (SCFAs) in stool; restored motilin (MTL) and vasoactive intestinal peptide (VIP) levels; and downregulated interleukin 6 (IL-6) and IL-8 levels in serum. This repaired the inflammatory response caused by constipation. Finally, it promoted peristalsis of the gastrointestinal tract, increasing stool water content, and relieving constipation. While Lactobacillus-dominated formula PB2 mainly restored the levels of serum neurotransmitters (MTL, SP (substance P), VIP and PYY (Peptide YY)) and inflammatory factors (IL-1, IL-6 and IL-8), it significantly decreased the relative abundance of Tyzzerella, Enterorhabdus, Faecalibaculum, Gordonibacter and Mucispirillum in stool; it then increased acetic acid content, thereby reducing the level of inflammation and changing stool properties and gastrointestinal motility.


Assuntos
Gastroenteropatias , Probióticos , Animais , Camundongos , Loperamida/efeitos adversos , Lactobacillus , Bifidobacterium , Interleucina-6 , Interleucina-8 , Constipação Intestinal/microbiologia , Probióticos/uso terapêutico
4.
Technol Health Care ; 2023 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-37483035

RESUMO

BACKGROUND: Radical resection of lung cancer and chemotherapy are the main methods for the treatment of early lung cancer, but surgical treatment is still the key and preferred method. OBJECTIVE: To evaluate the efficacy and safety of robotic-assisted thoracic surgery (RATS) and video assisted thoracic surgery (VATS) for non-small cell lung cancer (NSCLC). METHODS: The clinical cohort studies on the comparison of the effects of RATS and VATS in the treatment of NSCLC published in Web of Science, PubMed, The National Library of Medicine (NLM), China National Knowledge Infrastructure (CNKI) and Wanfang database from January 1, 2015 to December 31, 2022 were searched. Two researchers independently screened the literature, extracted the data, such as operation time, intraoperative conversion rate, intraoperative blood loss, number of lymph nodes dissected, and evaluated the quality of the included literature based on the Newcastle-Ottawa Scale (NOS). RevMan 5.3 software was used for Meat analysis. RESULTS: A total of 18 articles and 21,802 subjects were included. The results of the meta-analysis showed that the intraoperative blood loss of RATS was significantly less than that of VAS, and the difference was statistically significant [MD =-38.43 (95% CI: -57.71, -19.15, P< 0.001)]. Compared with VATS, the number of lymph nodes dissected in RATS was significantly higher [MD = 2.61 (95% CI: 0.47, 4.76, P= 0.02)]. The rate of conversion to thoracotomy in RATS was lower, and the difference was statistically significant [OR = 0.59 (95% CI: 0.50, 0.70, P< 0.001)]. There was no significant difference between RATS and VATS in operation time [MD =-9.34 (95% CI: -28.72, 10.04, P= 0.34)], postoperative thoracic drainage time [MD =-0.08 (95% CI: -0.42, 0.26, P= 0.64)], postoperative hospital stay [MD =-0.05 (95% CI: -0.19, 0.08, P= 0.42)], postoperative mortality [OR = 0.88 (95% CI: 0.56, 1.36, P= 0.56)] and postoperative complications [OR = 1.03 (95% CI: 0.93, 1.13, P= 0.57)]. CONCLUSION: Compared with VATS, the number of lymph nodes dissected in RATS was significantly more, and the removal of lesions and lymph nodes was more thorough and accurate. More flexible and precise operation avoids the injury of important blood vessels during operation, effectively reduces the amount of blood loss during operation, shortens the indwelling time of thoracic drainage tube, and is conducive to postoperative rehabilitation of patients.

5.
BMC Oral Health ; 23(1): 30, 2023 01 19.
Artigo em Inglês | MEDLINE | ID: mdl-36658579

RESUMO

BACKGROUND: Severe early childhood caries (SECC) is an inflammatory disease with complex pathology. Although changes in the oral microbiota and metabolic profile of patients with SECC have been identified, the salivary metabolites and the relationship between oral bacteria and biochemical metabolism remains unclear. We aimed to analyse alterations in the salivary microbiome and metabolome of children with SECC as well as their correlations. Accordingly, we aimed to explore potential salivary biomarkers in order to gain further insight into the pathophysiology of dental caries. METHODS: We collected 120 saliva samples from 30 children with SECC and 30 children without caries. The microbial community was identified through 16S ribosomal RNA (rRNA) gene high-throughput sequencing. Additionally, we conducted non-targeted metabolomic analysis through ultra-high-performance liquid chromatography combined with quadrupole time-of-flight mass spectrometry to determine the relative metabolite levels and their correlation with the clinical caries status. RESULTS: There was a significant between-group difference in 8 phyla and 32 genera in the microbiome. Further, metabolomic and enrichment analyses revealed significantly altered 32 salivary metabolites in children with dental caries, which involved pathways such as amino acid metabolism, pyrimidine metabolism, purine metabolism, ATP-binding cassette transporters, and cyclic adenosine monophosphate signalling pathway. Moreover, four in vivo differential metabolites (2-benzylmalate, epinephrine, 2-formaminobenzoylacetate, and 3-Indoleacrylic acid) might be jointly applied as biomarkers (area under the curve = 0.734). Furthermore, the caries status was correlated with microorganisms and metabolites. Additionally, Spearman's correlation analysis of differential microorganisms and metabolites revealed that Veillonella, Staphylococcus, Neisseria, and Porphyromonas were closely associated with differential metabolites. CONCLUSION: This study identified different microbial communities and metabolic profiles in saliva, which may be closely related to caries status. Our findings could inform future strategies for personalized caries prevention, detection, and treatment.


Assuntos
Cárie Dentária , Microbiota , Criança , Pré-Escolar , Humanos , Cárie Dentária/microbiologia , Suscetibilidade à Cárie Dentária , Saliva/química , Microbiota/genética , Metaboloma , RNA Ribossômico 16S/genética , Biomarcadores
7.
Micromachines (Basel) ; 12(12)2021 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-34945405

RESUMO

Ultrafast, high-sensitivity deep-ultraviolet (UV) photodetectors are crucial for practical applications, including optical communication, ozone layer monitoring, flame detection, etc. However, fast-response UV photodetectors based on traditional materials suffer from issues of expensive production processes. Here, we focused on pyrite with simultaneously cheap production processes and ultrafast response speed. Nanoseconds photovoltaic response was observed under UV pulsed laser irradiation without an applied bias at room temperature. In addition, the response time of the laser-induced voltage (LIV) signals was ~20 ns, which was the same as the UV laser pulse width. The maximum value of the responsivity is 0.52 V/mJ and the minimum value of detectivity was about to ~1.4 × 1013 Jones. When there exists nonuniform illumination, a process of diffusion occurs by which the carriers migrate from the region of high concentration toward the region of low concentration. The response speed is limited by a factor of the diffusion of the carriers. With an increment in laser energy, the response speed of LIV is greatly improved. The high response speed combined with low-cost fabrication makes these UV photodetectors highly attractive for applications in ultrafast detection.

8.
Anim Cogn ; 22(1): 71-79, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30460512

RESUMO

Vocal individuality is a prerequisite for individual recognition, especially when visual and chemical cues are not available or effective. Vocalizations encoding information of individual identity have been reported in many social animals and should be particularly adaptive for species living in large and complexly organized societies. Here, we examined the individuality in coo calls of adult male golden snub-nosed monkeys (Rhinopithecus roxellana) living in a large and multilevel society. Coo calls are one of the most frequently occurring call types in R. roxellana and likely serve as the signals for contact maintenance or advertisement in various contexts including group movement, foraging, and resting. From April to October 2016, April to July 2017, and September to October 2017, we recorded a total of 721 coo calls from six adult males in a provisioned, free-ranging group and one adult male in captivity in Shennongjia National Park, China. We selected 162 high-quality recordings to extract 14 acoustic parameters based on the source-filter theory. Results showed that each of all parameters significantly differed among individuals, while pairwise comparisons failed to detect any parameter that was different between all pairs. Furthermore, a discriminant function analysis indicated that the correct assignment rate was 80.2% (cross-validation: 67.3%), greater than expected by chance (14.3%). In conclusion, we found evidence that coo calls of adult male R. roxellana allowed the reliable accuracy of individual discrimination complementarily enhanced by multiple acoustic parameters. The results of our study point to the selective pressures acting on individual discrimination via vocal signals in a highly gregarious forest-living primate.


Assuntos
Colobinae/fisiologia , Individualidade , Vocalização Animal/fisiologia , Acústica , Animais , China , Masculino
9.
Zool Res ; 40(2): 121-128, 2019 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-29955030

RESUMO

Knowledge on the home range size of a species or population is important for understanding its behavioral and social ecology and improving the effectiveness of conservation strategies. We studied the home range size of two different-sized groups of golden snub-nosed monkeys (Rhinopithecus roxellana) in Shennongjia, China. The larger group (236 individuals) had a home range of 22.5 km2 from September 2007 to July 2008, whereas the smaller group (62 individuals) occupied a home range of 12.4 km2 from November 2008 to July 2009. Both groups exhibited considerable seasonal variation in their home range size, which was likely due to seasonal changes in food availability and distribution. The home range in any given season (winter, spring, summer, or winter+spring+summer) of the larger group was larger than that of the smaller group. As the two groups were studied in the same area, with the confounding effects of food availability thus minimized, the positive relationship between home range size and group size suggested that scramble feeding competition increased within the larger group.


Assuntos
Comportamento Animal , Colobinae/fisiologia , Comportamento Alimentar , Territorialidade , Animais , China , Atividade Motora , Estações do Ano
10.
Am J Primatol ; 80(6): e22869, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29767431

RESUMO

Vocal signaling represents a primary mode of communication for most nonhuman primates. A quantitative description of the vocal repertoire is a critical step in in-depth studies of the vocal communication of particular species, and provides the foundation for comparative studies to investigate the selective pressures in the evolution of vocal communication systems. The present study was the first attempt to establish the vocal repertoire of free-ranging adult golden snub-nosed monkeys (Rhinopithecus roxellana) based on quantitative methods. During 8 months in Shennongjia National Park, China, we digitally recorded the vocalizations of adult individuals from a provisioned, free-ranging group of R. roxellana across a variety of social-ecological contexts. We identified 18 call types, which were easily distinguishable by ear, visual inspection of spectrograms, and quantitative analysis of acoustic parameters measured from recording samples. We found a great sexual asymmetry in the vocal repertoire size (females produced many more call types than males), likely due to the sex differences in body size and social role. We found a variety of call types that occurred during various forms of agonistic and affiliative interactions at close range. We made inference about the functions of particular call types based on the contexts in which they were produced. Studies on the vocal communication in R. roxellana are particularly valuable since they provide a case about how nonhuman primates, inhabiting forest habitats and forming complex social systems, use their vocalizations to interact with their social and ecological environments.


Assuntos
Colobinae/fisiologia , Comportamento Social , Vocalização Animal/classificação , Animais , China , Feminino , Masculino , Caracteres Sexuais , Espectrografia do Som
11.
Am J Primatol ; 80(4): e22753, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29635791

RESUMO

The gastrointestinal tract of primates harbors a complex microbial community, playing an essential role in the degradation of otherwise indigestible structural carbohydrates. The phylogenetic and functional diversity of the bacterial community in the feces as a surrogate for the gastrointestinal tract of wild Sichuan snub-nosed monkeys (Rhinopithecus roxellana, N = 6) was characterized based on sequence analysis of 16S rRNA genes. A sex comparison was conducted, with a prior hypothesis that the abundances of the bacterial taxa and/or functional categories associated with energy and nutrient metabolism would be higher in adult females (N = 3) due to the higher reproductive costs compared to adult males (N = 3). Ten phyla were identified in all samples, among which Bacteroidetes and Firmicutes were the predominant. Included in the above two phyla, the members of Prevotellaceae (Prevotella in particular) and Ruminococcaceae were highly abundant, which are common bacteria in the gastrointestinal tract of primates and can degrade various structural carbohydrates such as cellulose, hemicellulose, and pectin. This functionality was in line with the high abundances of the metagenomes associated with carbohydrate metabolism. Consistent with our hypothesis, the abundances of the metagenomes associated with energy metabolism, folding/sorting and degradation, glycan biosynthesis and metabolism, and metabolism of amino acids were higher in adult females relative to adult males. Sex differences were also detected in the bacterial community structure, although no sex differences in the proportions of any bacterial taxa were found likely due to the small sample size. These results suggested that gastrointestinal bacterial communities may aid adult females in increasing energy and nutrition utilization efficiencies compared to adult males. Fecal bacterial communities were found to be more similar between individuals in adult females than in adult males. Our study presented the first examination of the fecal bacterial diversity of a little-studied, endangered foregut fermenter.


Assuntos
Bactérias/classificação , Colobinae/microbiologia , Fezes/microbiologia , Animais , Bactérias/genética , China , Feminino , Microbioma Gastrointestinal , Masculino , Filogenia , RNA Ribossômico 16S , Fatores Sexuais
12.
Int J Biol Macromol ; 108: 1082-1091, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29128589

RESUMO

The aim of the present work was to develop gastric floating capsules containing oil-entrapped beads loading procyanidins. The floating beads were prepared by ionotropic gelation method using sodium alginate, CaCl2 and chitosan. The effect of three independent parameters (concentration of sodium alginate, CaCl2 and chitosan) on entrapment efficiency were analyzed by Box-Behnken design. The floating beads were evaluated for surface morphology, particle size, density, entrapment efficiency, buoyancy, release behavior in vitro and floating ability in vivo. The prepared beads were grossly spherical in shape and the mean size was approximately 1.54±0.17mm. The density was 0.97g/cm3. And the optimal conditions were as follows: concentration of sodium alginate, CaCl2 and chitosan were 33.75mg/mL, 9.84mg/mL and 9.05mg/mL, respectively. The optimized formulation showed entrapment efficiency of 88.84±1.04% within small error-value (0.65). The release mechanism of floating capsules followed Korsmeyer-Peppas model (r2=0.9902) with non-Fickian release. The gastric floating capsules exhibited 100% floating percentage in vitro and they could float on the top of gastric juice for 5h in vivo. Therefore, the floating capsules are able to prolong the gastroretentive delivery of procyanidins.


Assuntos
Alginatos/química , Biflavonoides/química , Catequina/química , Quitosana/química , Portadores de Fármacos/química , Mucosa Gástrica/metabolismo , Óleos/química , Proantocianidinas/química , Cápsulas , Composição de Medicamentos , Ácido Glucurônico/química , Ácidos Hexurônicos/química , Estatística como Assunto , Propriedades de Superfície
13.
Prep Biochem Biotechnol ; 47(9): 881-888, 2017 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-28708469

RESUMO

In this study, an efficient ultrasound-assisted aqueous two-phase extraction method was used for the extraction of anthocyanins from Lycium ruthenicum Murr. An ethanol/ammonium sulfate system was chosen for the aqueous two-phase system due to its fine partitioning and recycling behaviors. Single-factor experiments were conducted to determine the optimized composition of the system, and the response surface methodology was used for the further optimization of the ultrasound-assisted aqueous two-phase extraction. The optimal conditions were as follows: a salt concentration of 20%, an ethanol concentration of 25%, an extraction time of 33.7 min, an extraction temperature of 25°C, a liquid/solid ratio of 50:1 w/w, pH value of 3.98, and an ultrasound power of 600 W. Under the above conditions, the yields of anthocyanins reached 4.71 mg/g dry sample. For the further purification, D-101 resin was used, and the purity of anthocyanins reached 25.3%. In conclusion, ultrasound-assisted aqueous two-phase extraction was an efficient, ecofriendly, and economical method, and it may be a promising technique for extracting bioactive components from plants.


Assuntos
Antocianinas/isolamento & purificação , Fracionamento Químico/métodos , Lycium/química , Extratos Vegetais/química , Sonicação/métodos , Sulfato de Amônio/química , Etanol/química , Transição de Fase
14.
Primates ; 57(4): 479-87, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27056265

RESUMO

Age-sex differences in diet have been reported in many nonhuman primates, and body size, reproductive costs, and growth are three mutually non-exclusive factors often proposed to explain such differences. Smaller animals tend to feed on high quality foods (high in protein/energy) more often than larger animals due to their higher metabolic requirements per body weight. Animals of different sizes tend to use different substrate levels, leading to dietary differences if food resources are unevenly distributed along substrate levels. Adult females and juveniles experience additional metabolic requirements for reproduction and growth, respectively, and tend to feed on high quality foods more frequently than adult males. We conducted an age-sex analysis for the diet of Sichuan snub-nosed monkeys (Rhinopithecus roxellana) in Shennongjia, China. In spite of general age-sex similarities, we found that adult males ate herbs more frequently than juveniles and adult females, most likely because they were more terrestrial. As predicted, juveniles ate high quality foods (young leaves, fruits, seeds, and buds) more frequently, and meanwhile ate low quality foods (barks and lichens) less frequently than adult males across the study year or in some seasons when these food types were eaten. However, we found high similarities in diet between adult females and adult males. The most likely reason was that the low diversity of food sources and strong phenological synchrony did not allow adult females to select foods based on quality to cope with their higher metabolic constraints compared to adult males. Surprisingly, the only sex difference in diet except herbs was that adult females ate lichens more frequently in autumn. One plausible reason was that lactating females experienced their highest metabolic requirements in the middle period of infant care (autumn), and had to disproportionately increase the intake of lichens due to the limited availability of plant foods.


Assuntos
Colobinae/fisiologia , Dieta , Fatores Etários , Animais , China , Feminino , Masculino , Parques Recreativos , Fatores Sexuais
15.
Am J Primatol ; 75(8): 860-71, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23589133

RESUMO

The diet of Rhinopithecus roxellana is characterized by lichens, which are available year-round and an uncommon food source for nonhuman primates, supplemented by seasonal plant foods. We present the first study of foods eaten by R. roxellana in relation to nutritional chemistry in Shennongjia National Nature Reserve, Hubei Province, China. We analyzed the nutrients (crude protein, crude fat, and water soluble carbohydrate [WSC]) and feeding deterrents (crude fiber, condensed tannin [CT], and total phenolic [TP]) of 111 parts from 53 plant species and of 6 lichen species. Results showed that lichens were a good choice for R. roxellana living in habitats with limited and seasonally available plant foods. They contained higher concentrations of WSC than foliage, fat concentrations equivalent to those in plant parts (except fruits/seeds), and lower concentrations of fiber than mature leaves, flowers, and fruits. Although lichens were lower in protein than plant parts (except fruits), the monkeys could likely meet their protein requirement by eating seasonal plant foods rich in protein, including foliage, flowers, buds, and seeds. The monkeys were not observed to select foliage higher in protein, but appeared to select mature leaves higher in WSC and lower in fiber. Fruits were a good source of WSC and fat, and seeds were a good source of fat. Neither CT nor TP content showed negative effects on the selection of mature leaves or lichens.


Assuntos
Colobinae/fisiologia , Comportamento Alimentar , Preferências Alimentares , Animais , Feminino , Análise de Alimentos , Líquens/química , Masculino , Valor Nutritivo , Componentes Aéreos da Planta/química
16.
Am J Primatol ; 73(12): 1280-8, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21898518

RESUMO

Most Old World monkeys show male-biased dispersal. We present the first systematic data on male dispersal in a provisioned multilevel group of Rhinopithecus roxellana, based on 4.5 years of field observations in Shennongjia National Nature Reserve, China. We evaluated both ultimate (inbreeding avoidance and male mating competition) and proximate (food availability and predation risk) factors influencing male dispersal. The focal group contained 34-53 individuals, in 3-4 one-male units (OMUs) and 1 all-male unit (AMU). We observed 37 dispersal events involving 10 of 11 adults, 7 of 8 subadults, and 7 of 15 juveniles. Most interunit transfers within the focal group occurred around the months of mating season. Adult males competed for the leader positions of OMUs mainly through aggressive takeovers, and young males transferred from the OMUs to the AMU at the median age of 41 months, forced out by leader males. No young males older than 4 years remained in natal or non-natal OMUs. The male mating competition hypothesis was supported. The young males emigrated voluntarily from the focal group at the average age of 58.6 months, and no young emigrating male was observed to return, suggesting inbreeding avoidance also played a role in the dispersal of young males. Most emigration/immigration events were parallel dispersal and occurred during intergroup encounters, suggesting increased predation risk during the dispersal period. Males were more likely to emigrate/immigrate during the months when preferred foods were most available. We compared the dispersal patterns in R. roxellana with those in gelada baboons and hamadryas baboons, both living in multilevel societies. Similar to R. roxellana, young male geladas disperse at puberty, but they may return and breed in their natal groups. Males in hamadryas also disperse, but much less commonly than in R. roxellana. Provisioning may have influenced results, and confirming studies on unprovisioned groups would be valuable.


Assuntos
Comportamento Animal , Colobinae/psicologia , Comportamento Social , Fatores Etários , Animais , China , Masculino , Dinâmica Populacional
17.
Am J Primatol ; 71(6): 523-6, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19266499

RESUMO

Natural disasters can negatively affect primate population demography and social group structure. A clear understanding of these effects has important implications for wildlife conservation. The worst snow storms in nearly five decades hit portions of southern and central China between January 10 and February 6, 2008, presenting a unique opportunity to observe their immediate effects on a previously studied group of Hubei Golden Snub-nosed Monkeys (Rhinopithecus roxellana hubeiensis) in temperate forests in Shennongjia Nature Reserve, Hubei Province, China. We recorded social and demographic characteristics of the group before and after the snow storms. The average group size decreased from 270 individuals before the storms to 197 individuals after the storms, a reduction of 27.2%. Adult females (30.1%), juveniles (38.1%) and infants (55.4%) suffered higher mortality than did adult males (15.7%). Despite age and sex-based differences in mortality, the ratios of adult males to adult females, adults to immatures and adult females to immatures remained similar before and after the storms. However, higher mortality among females, juveniles and infants may reduce the group's long-term potential for growth.


Assuntos
Desastres , Haplorrinos/crescimento & desenvolvimento , Neve , Animais , China , Feminino , Masculino , Densidade Demográfica
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