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1.
Food selection in folivorous primates has been hypothesized to be correlated with leaf chemistry. To test this hypothesis,
we conducted a 5-month study on Presbytis entellusin a moist deciduous forest in the Rajaji National Park,Uttar Pradesh, India. The study period covered two seasons, winter and spring. We used the percentage time spent feeding on
each food item as an index of food selection, which we estimated from group scan data collected from one study group for 6
days each month. We estimated the selection ratio for each item as the ratio of time spent feeding to availability. We estimated
food availability from vegetation sampling and phenological data in the home range of the study group. We estimated crude
protein (CP), acid detergent fiber (ADF) and tannins in mature and young leaves of 12 major food species in the laboratory.
Food selection is positively correlated with CP in winter and negatively correlated with ADF in both seasons. It also is correlated
with CPJADF ratio, but to a lesser extent than the best predictor in winter and spring. Selection ratio is not correlated
with CP and ADF in both seasons. It is probable that the inclusion of other factors, such as micronutrients,condensed tannins, and digestibility, might give a better prediction of food selection. 相似文献
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Infant development in lion-tailed monkeys was observed during the first eight weeks after birth. A rapid decrease in the time
spent in the closest association by the mother and the infant was seen between the first and second weeks. Between the second
and fifth week there was a somewhat steady state with only marginal decrease in the time spent by the infant out of lap of
the mother. However, during this time, a rapid decline in maternal cradling and restraining behaviour was seen. From the sixth
week onwards, there was a rapid increase in the time spent by the infant out of contact with the mother. Independence of the
infant during troop progression was seen only towards the eighth week, that too only marginal. Among the troop members the
subadult females and the juvenile females showed the maximum interest in the infant. The former spent much more time than
the juveniles interacting with the infant. The adult females showed only little interest in the infant while the adult male
showed no interest at all. Infant snatching by subadult females and juvenile females was seen on many occasions. The infant
remained in the possession of them from less than 1 min to more than 2 hr. This behaviour tended to decrease towards the sixth
week. 相似文献
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The availability of refuges from predators and high quality food are thought to determine habitat use in small ungulates. We tested this hypothesis on habitat use by the Indian chevrotain in a tropical rainforest in the Western Ghats, using pellet-groups to infer habitat use. Between December 2009 and April 2010, we sampled 204 grids of 50 m × 50 m with four spatial replicates in each, using occupancy framework. We quantified refuges such as fallen logs and boulders, understorey complexity, and noted the presence of fruiting trees in the grid. Detection probability, p, of pellet-groups was estimated at 0.61. The naive estimate of occupancy was 0.52, which increased to 0.73 when p was accounted for. Out of eight candidate models compared using AICC, the one with the number of refuges and understorey complexity was the best model. Both covariates had non-zero positive slopes. Fruiting trees occurred very infrequently and did not influence habitat use, perhaps because the chevrotain fed more on buds, shoots and young leaves during the dry period covered by this study. The strong influence of understorey complexity on habitat use was perhaps also due to the abundance of these food items. These results highlight the need to control human use that adversely impacts the availability of refuges and understorey complexity such as removal of fallen logs and rattans. This study also demonstrates the application of the occupancy approach in the study of small and elusive ungulates. 相似文献
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Ajith Anand Emily Wu Zhi Li Sue TeRonde Maren Arling Brian Lenderts Jasdeep S. Mutti William Gordon‐Kamm Todd J. Jones Nicholas Doane Chilcoat 《Plant biotechnology journal》2019,17(8):1636-1645
An efficient Agrobacterium‐mediated site‐specific integration (SSI) technology using the flipase/flipase recognition target (FLP/FRT) system in elite maize inbred lines is described. The system allows precise integration of a single copy of a donor DNA flanked by heterologous FRT sites into a predefined recombinant target line (RTL) containing the corresponding heterologous FRT sites. A promoter‐trap system consisting of a pre‐integrated promoter followed by an FRT site enables efficient selection of events. The efficiency of this system is dependent on several factors including Agrobacterium tumefaciens strain, expression of morphogenic genes Babyboom (Bbm) and Wuschel2 (Wus2) and choice of heterologous FRT pairs. Of the Agrobacterium strains tested, strain AGL1 resulted in higher transformation frequency than strain LBA4404 THY‐ (0.27% vs. 0.05%; per cent of infected embryos producing events). The addition of morphogenic genes increased transformation frequency (2.65% in AGL1; 0.65% in LBA4404 THY‐). Following further optimization, including the choice of FRT pairs, a method was developed that achieved 19%–22.5% transformation frequency. Importantly, >50% of T0 transformants contain the desired full‐length site‐specific insertion. The frequencies reported here establish a new benchmark for generating targeted quality events compatible with commercial product development. 相似文献
8.
CpG island methylation in a mouse model of lymphoma is driven by the genetic configuration of tumor cells 下载免费PDF全文
9.
Jayakumar T. T. K. Shakhovskoy I. B. Prasoon N. P. K. Kathirvelpandian A. Ajith Kumar T. T. Lal K. K. 《Journal of Ichthyology》2019,59(5):697-706
Journal of Ichthyology - The present study reports the first record of the rearfin flying fish, Cypselurus opisthopus (Bleeker, 1865), in the south-eastern Arabian Sea based on a single specimen... 相似文献
10.
Anand A Lei Z Sumner LW Mysore KS Arakane Y Bockus WW Muthukrishnan S 《Molecular plant-microbe interactions : MPMI》2004,17(12):1306-1317
A transgenic wheat line constitutively expressing genes encoding a class IV acidic chitinase and an acidic beta-1,3-glucanase, showed significant delay in spread of Fusarium head blight (scab) disease under greenhouse conditions. In an earlier work, we observed a lesion-mimic phenotype in this transgenic line when homozygous for transgene loci. Apoplastic fluid (AF) extracted from the lesion-mimic plants had pathogenesis-related (PR) proteins belonging to families of beta-1,3-glucanases, chitinases, and thaumatin-like proteins (TLPs). AF had growth inhibitory activity against certain fungal pathogens, including Fusarium graminearum and Gaeumannomyces graminis var. tritici. Through a two-step ion-exchange chromatography protocol, we recovered many PR proteins and a few uncharacterized proteins. Three individual protein bands corresponding to a TLP (molecular mass, 16 kDa) and two beta-1,3-glucanases (molecular mass, 32 kDa each) were purified and identified by tandem mass spectrometry. We measured the in vitro antifungal activity of the three purified enzymes and a barley class II chitinase (purified earlier in our laboratory) in microtiter plate assays with macroconidia or conidiophores of F. graminearum and Pyrenophora tritici-repentis. Mixtures of proteins revealed synergistic or additive inhibitory activity against F. graminearum and P. tritici-repentis hyphae. The concentrations of PR proteins at which these effects were observed are likely to be those reached in AF of cells exhibiting a hypersensitive response. Our results suggest that apoplastic PR proteins are antifungal and their antimicrobial potency is dependent on concentrations and combinations that are effectively reached in plants following microbial attack. 相似文献