The elegant water shrew, Nectogale elegans, is one of the small mammal species most adapted to a semi‐aquatic lifestyle. The taxonomy of the genus Nectogale has received little attention due to ...difficulties in specimen collection. In this study, we sequenced one mitochondrial and eight nuclear genes to infer the phylogenetic relationship of Nectogale. Phylogenetic analyses revealed two large clades within Nectogale. One clade represented N. elegans, and the other was regarded as N. sikhimensis. The split between N. elegans and N. sikhimensis dated back to the early Pleistocene (2.15 million years ago Ma), which might be relevant to the Qinghai‐Tibet Plateau (QTP) uplift. The morphological comparison showed several distinguishing characters within Nectogale: the shape of the mastoids, the first lower unicuspid (a1), and the second upper molar (M2). Overall, the molecular and the morphological evidences supported that the genus Nectogale consists of two valid species: N. elegans and N. sikhimensis.
We recover species status of Nectogale sikhimensis using molecular and morphometric analyses, and the genus Nectogale consists of two valid species, N. elegans and N. sikhimensis.
Sacred natural sites, as probably the oldest form of habitat reserve for religious or cultural causes worldwide, are suggested to have an important role in conserving vegetation; however, there are ...insufficient data supporting the detailed implications of such sites for vegetation conservation. Thus, we evaluated the effectiveness of vegetation conservation on a Tibetan sacred mountain in Yajiang County, Sichuan, China, by investigating species richness and the structural attributes of higher vascular plant communities on and around the sacred mountain from April to June 2009. The results showed that the number of tree species on the sacred mountain was significantly higher than that in the surrounding area, but there were no notable differences in the numbers of shrub and grass species between the two sites. The sacred mountain harbored a greater number of small, short trees compared with the surrounding area, wherein the low-shrub and grass understory was relatively dense. We conclude that the sacred mountain has a positive impact on indigenous vegetation protection, but disparities in the management of the allowed uses of such sites could reduce their conservation effectiveness.
At present, there are a large number of exercises on the existing programming Online Judge systems（OJ）,which makes it difficult for students to quickly find suitable exercises according to their own ...knowledge level and learning demand.Therefore, it is necessary to design a model to recommend suitable exercises to students.However, due to uniqueness of OJ and complexity of programming ability evaluation, existing recommendation model can not complete OJ exercise recommendation task well, the main problems include: OJ exercises' lack of knowledge label and unique proposition style make it difficult for existing models to mine correlation between exercises; actual correctness of the program submitted by student is inconsistent with OJ judgement result, which leads to deviation of students' knowledge state estimated by models; existing models are difficult to provide exercises that increase students' programming ability most significantly.Based on this, this paper proposes an OJ exercise recommendation model base
The climbing mouse is a rare, small mammal listed as an endangered species on the China species red list. Molecular phylogenetic analyses and the evolutionary history of the genus remain unexplored ...because of the extreme difficulty in capturing individuals and their narrow distribution. Here, we collected 44 specimens, sequenced one mitochondrial and eight nuclear genes, and integrated morphological approaches to estimate phylogenetic relationships, delimit species boundaries, and explore evolutionary history. Molecular analyses and morphological results supported the validity of these four species. Here, we describe two new species, Vernaya meiguites sp. nov. and Vernaya nushanensis sp. nov., and recognize Vernaya foramena, previously considered a subspecies of Vernaya fulva, as a valid species. The estimated divergence time suggests that the climbing mouse began to diversify during the Pliocene (3.36 Ma).
The climbing mouse (genus Vernaya) is one of the least studied small mammals. This manuscript integrates molecular and morphological approaches to study the phylogeny and taxonomy of the genus. They described two new species and recognized Vernaya foramena as a valid species. It makes a potentially important contribution to our understanding of the systematics of the genus Vernaya.
A novel nonlinear electrical equalizer (NLEE) based on Volterra theory is proposed for mitigating intra-channel nonlinearities in pseudo-linear coherent optical communication systems. According to ...the temporal matching condition of intra-channel nonlinear pulse interactions, we just select specific nonlinear terms and reduce the computation complexity considerably. Numerical simulations of 10GBaud coherent quadrature phase-shift keying (QPSK) transmission show that the simplified NLEE can efficiently mitigate intra-channel nonlinearities.
Our goal was to document effects of year-round supplemental feeding on breeding ecology of the Buff-throated Partridge, Tetraophasis szechenyii, within a Tibetan sacred site. We evaluated effects of ...supplemental feeding used as religious/cultural practices which could potentially aid conservation of endangered phasianids. We compared fed breeding groups to neighboring nonfed groups. Fed groups initiated first clutches significantly earlier than nonfed groups. Earlier laying groups within fed and nonfed groups showed significantly lower hatching rates than later groups; however, fed groups showed significantly higher hatching rates than nonfed groups laying in the same period. Earlier laying increased opportunities to renest. All six fed groups with clutch failures renested compared to only one of five nonfed groups with clutch failures. Fed female breeders showed significantly greater investment in their young with larger clutches and larger eggs, which likely increased survivability of early hatchlings. We observed no predation on birds at feeding sites and recorded only four cases of predation on incubating females, which showed no detectable difference between fed and nonfed groups. Ground-nesting birds typically face high risks of predation. Ten of the 48 groups nested in trees, which occurs in few phasianid species. Tree nests showed significantly higher hatching rates compared to ground nests; however, we found no significant difference in tree nesting between fed and nonfed groups. This partridge is one of four gallinaceous species with cooperative breeding. Breeding groups with helpers had significantly greater reproductive success than single pairs, and fed female breeders with helpers laid bigger eggs than single pairs. Comparing annual reproductive output per group, fed groups not only produced significantly more independent young (≥ 150 days post-hatching), their young hatched significantly earlier, which likely have greater reproductive value over later hatched young of nonfed groups. Supplemental feeding year-round is likely what enabled the successes of the fed partridges.
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Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Circular dichroism (CD) spectroscopy is a well-known and powerful technique widely used for distinguishing chiral enantiomers based on their differential absorbance of the right and left circularly ...polarized light. With the increasing demand for solid-state chiral optics, CD spectroscopy has been extended to elucidate the chirality of solid-state samples beyond the traditional solution state. However, due to the sample preparation differential, the CD spectra of the same compound measured by different researchers may not be mutually consistent. In this study, we employ solution, powder, thin-film, and single-crystal samples to explore the challenges associated with CD measurements and distinguish between genuine and fake signals. Rational fabrication of the solid-state samples can effectively minimize the macroscopic anisotropic nature of the samples and thereby mitigate the influence of linear dichroism (LD) and linear birefringence (LB) effects, which arise from anisotropy-induced differences in the absorbances and refractive indices. The local anisotropic and overall isotropic features of the high-quality thin-film sample achieve an optically isotropic state, which exhibits superior CD signal repeatability at the front and back sides at different angles by rotating the sample along the light path. In addition, sample thickness-induced CD signal overload and absorption saturation pose more severe challenges than the LBLD-induced amplified CD signal but are rarely focused on. The CD signal overload in the deep UV region leads to the presence of fake signals, while absorption saturation results in a complete loss of the CD signal. These findings help obtain accurate CD signals by a well-fabricated optically isotropic sample to avoid LDLB and optimize the sample thickness to avoid fake signals and no signals.
Tibetan sacred mountains, the unique landforms influenced by the Buddhist religion in many Himalayan regions, are suggested to have great potential for preserving animal diversity. Yet, a bias might ...lie in evaluating the effectiveness of such areas, given the local culture of respect for, and protection of, wildlife, resulting in many animals that are relatively tame and, thus, easier to be detected visually compared with other regions. Here, we provide the first assessment of this issue, using Galliformes as a representative taxon on a typical Tibetan sacred mountain in western China. We estimated diversity of Galliformes relying on direct sightings versus an indirect technique of counting feathers, which avoids detectability issues associated with habitat and tameness of species. The data from direct sightings showed a higher relative abundance on the sacred mountain compared with its surrounding matrix, whereas the indirect technique of counting feathers suggested no considerable gains in species richness and abundance on the sacred mountain. Given the bias, we suggest that the biodiversity effects of Tibetan sacred mountains should be revisited. For management practices, we suggest that care will be needed to link Tibetan sacred mountains with conservation efforts. Keywords: Abundance, Conservation, Detectability, Human habituation, Richness, Sacred site
While there have been increasing numbers of reports of human-wolf conflict in China during recent years, little is known about the nature of this conflict. In this study, we used questionnaires and ...semi-structured interviews to investigate local villagers' perceptions of wolves in Jiuzhaigou County, western China. We sampled nine villages with more frequent reports of wolf depredation to the local government, but included three villages near alpine pastures in which reports of depredation were less frequent. We sampled 100 residents, a subset of the local population who were more likely to have had experience with wolves. During the preceding three years, most families of the respondents grazed livestock on alpine pastures, and most of them reported that their livestock suffered from depredation by wolves. The mean value of the reported annual livestock loss rates was considerably higher in villages that reported depredation more frequently than in those with less frequent reports of depredation. Most respondents in the more frequently depredated villages perceived an increase in wolf populations, whereas many in the less frequently depredated villages perceived a decrease in wolf populations in their areas. People's attitudes towards wolves did not differ significantly between these two village categories. The majority of the respondents were negative in their attitude to wolves, despite a prevalent Tibetan culture that favors the protection of wildlife. People's negative attitude was directly related to the number of livestock owned by their family. Those with a larger number of livestock were more likely to have a negative attitude towards wolves. Factors such as village category, ethnicity, age and education level did not influence people's attitudes to wolves. We suggest that improved guarding of livestock and provision of monetary support on human resources and infrastructure may mitigate human-wolf conflicts in this region.
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