ABSTRACT
Ag2Se is an intriguing material for room-temperature energy harvesting. Herein, we report the fabrication of Ag2Se nanorod arrays by glancing angle deposition technique (GLAD) followed by simple selenization in a two-zone furnace. Ag2Se planar films of different thickness were also prepared. The unique tilted Ag2Se nanorod arrays show excellent zT = 1.14 ± 0.09 and a power factor of 3229.21 ± 149.01 µW/m-K2, respectively, at 300 K. The superior thermoelectric performance of Ag2Se nanorod arrays compared to planar Ag2Se films could be ascribed to the unique nanocolumnar architecture that not only facilitates efficient electron transport but also significantly scatters phonons at the interfaces. Furthermore, the nanoindentation measurements were performed to explore mechanical properties of the as-prepared films. The Ag2Se nanorod arrays showed hardness values of 116.51 ± 4.25 MPa and elastic modulus of 10,966.01 ± 529.61 MPa, which are lowered by 51.8 and 45.6%, compared to Ag2Se films, respectively. The synergetic dependence between the tilt structure and thermoelectric properties accompanied with the simultaneous improvement in mechanical properties opens a new avenue for the practical applications of Ag2Se in next-generation flexible thermoelectric devices.
ABSTRACT
The conservation of large carnivores often requires precise and accurate estimates of their populations. Being cryptic and occurring at low population densities, obtaining an unbiased population estimate is difficult in large carnivores. To overcome the uncertainties in the conventional capture-recapture (CR) methods used to estimate large carnivore densities, more robust methods such as spatially explicit capture-recapture (SECR) framework are now widely used. We modeled the CR data of tiger (Panthera tigris tigris) and leopard (Panthera pardus fusca) in the SECR framework with biotic and abiotic covariates likely believed to influence their densities. An effort of 2,211 trap nights resulted in the capture of 33 and 38 individual tigers and leopards. A total of 95 and 74 detections of tigers and leopards were achieved using 35 pairs of camera traps. Tiger and leopard density were estimated at 4.71 ± 1.20 (3.05-5.11) and 3.03 ± 0.78 (1.85-4.99) per 100 km2. Our results show that leopard density increased with high road density, high terrain ruggedness and habitats with high percentage of cropland and natural vegetation. The tiger density was positively influenced by the mosaic of cropland and natural vegetation. This study provides the first robust density estimates of tiger and leopard within the study area. Our results support the notion that large carnivores can attain moderate densities within human-dominated regions around protected areas relying on domestic livestock. Broader management strategies aimed at maintaining wild prey in the human-dominated areas around protected areas are necessary for large and endangered carnivores' sustenance in the buffer zones around protected areas.
ABSTRACT
Time and space are essential niche dimensions along which species tend to coexist. We assessed spatiotemporal resource partitioning between leopards and lions and hypothesized the differential use of spatiotemporal resources by leopards with respect to lions. We used a systematic camera trap survey to collect the data at 50 sites. The data were analyzed using overlap indices, and non-parametric test statistics to assess the spatiotemporal associations. Leopard and lion were crepuscular and nocturnal in their activity pattern. They did not segregate temporally and showed substantially high overlap and strong temporal association. Leopard segregates with lion spatially by overlapping less and showing no association in space use at specific camera trap sites. Leopards showed preference for dense habitats, while the lion preferred both dense and open habitats. Leopard showed moderate-overlap and positive association with key prey species, i.e., chital and sambar. Lion, however showed low site-specific overlap and negative association with its crucial prey species, i.e., sambar and wild pig. We conclude that site-specific spatial partitioning along with differential affinities for habitat is helping leopards to partition their spatio-temporal resources with lions and hence facilitate coexistence of leopards with lions in Gir forest.
Subject(s)
Competitive Behavior , Lions/psychology , Panthera/psychology , Predatory Behavior , Territoriality , Animals , Forests , India , Time FactorsABSTRACT
Information on the level and distribution of genetic variation is important for conservation plan of captive population of an endangered species such as tiger and cheetah. We assayed the frequency of microsatellites in the genomic and genic sequences of wild cats (Panthera tigris, Acinonyx jubatus) and compared it with the domestic cat (Felis catus). Frequency, relative abundance and density of microsatellites were highest in the domestic cat when compared with wild cats. The frequency of microsatellites was positively correlated with the G+C content of genomic and genic sequences. The maximum frequency of microsatellites among all three sequence sets was of di-nucleotide repeats (genomic-88.1%; genic-70.4%), whereas the hexa-nucleotide repeat represents < 0.5%. Motif conservation study among the genomic and genic sequences revealed conservation of 81.3% and 51.0% motif within the members of family Felidae. A total 40,233 primers from genic sequences were designed in order to enrich the members of family Felidae with genomic resources. The designed primers could be useful in determining the molecular genetics of population structure and individualization of a particular cat.
