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Jaya K. Matthews Amanda Ridley Protais Niyigaba Beth A. Kaplin Cyril C. Grueter 《American journal of primatology》2019,81(4)
Almost all primates experience seasonal fluctuations in the availability of key food sources. However, the degree to which this fluctuation impacts foraging behavior varies considerably. Eastern chimpanzees (Pan troglodytes schweinfurthii) in Nyungwe National Park, Rwanda, live in a montane forest environment characterized by lower primary productivity and resource diversity than low‐elevation forests. Little is known about chimpanzee feeding ecology in montane forests, and research to date predominantly relies on indirect methods such as fecal analyses. This study is the first to use mostly observational data to examine how seasonal food availability impacts the feeding ecology of montane forest chimpanzees. We examine seasonal changes in chimpanzee diet and fallback foods (FBFs) using instantaneous scan samples and fecal analyses, supported by inspection of feeding remains. Chimpanzee fruit abundance peaked during the major dry season, with a consequent change in chimpanzee diet reflecting the abundance and diversity of key fruit species. Terrestrial herbaceous vegetation was consumed throughout the year and is defined as a “filler” FBF. In contrast to studies conducted in lower‐elevation chimpanzee sites, figs (especially Ficus lutea) were preferred resources, flowers were consumed at seasonally high rates and the proportion of non‐fig fruits in the diet were relatively low in the current study. These divergences likely result from the comparatively low environmental diversity and productivity in higher‐elevation environments. 相似文献
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The localization of lipid globules was studied in the adrenal glands from 35 fetuses and 10 adult humans by histochemistry. The fetal adrenal showed the presence of numerous lipid globules in the zona glomerulosa, whereas in the adult the lipid globules were mainly found in the zona fasciculata. These lipid globules were confirmed as cholesterol in the fetal adrenals. 相似文献
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Summary Germination of microsclerotia ofMacrophomina phaseolina was observed at O2 concentrations of 16% or higher in autoclaved soil. Germination was delayed but otherwise unaffected as O2 decreased from 21 to 16% and was in all cases complete in 32 hours. Laboratory-produced microsclerotia consistently germinated more rapidly and seemed more independent of O2 concentrations within the range that permitted germination than naturallyproduced microsclerotia.Population changes in soil as measured by microsclerotial counts were inversely correlated with depth of interment and reduced O2 concentration. Our inability to detect significantly growth responses ofM. phaseolina in non autoclaved soil was apparently related to limited O2 although other possibilities are discussed.Contribution of the Missouri Agricultural Experiment Station Scientific Journal Series No. 9124. 相似文献
5.
Germinability of the conidia of B. oryzae, after an efflux of substances — both electrolytes and non-electrolytes — was tested in sterilized solutions of plasmolytica and osmotica, ranging from molarity to 10?12 M. Maximum percent germination was recorded at 10?8 M concentration regardless of the exogenous supplement in the order KCl >D-glucose >Mannitol >NaCl. Germination was very poor or non-existent in other, higher or lower molarities tested except at 10?7 M wíth c. 50% germination. In nature the conidia, though nutrient independent, are subject to leaching and likely to lose viability; hence the possible role of the proper osmoticum, basing on the observed fact, in maintenance of membrane equilibrium and germinability of the leached conidia has been discussed. 相似文献
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A new species of the genus Cirrhimuraena (Anguilliformes: Ophichthidae) from the Bay of Bengal,India
Anil Mohapatra Swarup Ranjan Mohanty Dipanjan Ray Subhrendu Sekhar Mishra Jaya Kishor Seth 《Journal of fish biology》2021,98(5):1363-1370
A new species of the genus Cirrhimuraena (Anguilliformes: Ophichthidae), Cirrhimuraena indica sp. nov., is described based on eight specimens collected from the Paradip (Odisha) and Petuaghat harbours (West Bengal) along the Bay of Bengal. The species is distinct in having the upper jaw fringed with 16–17 cirri before posterior nostril and 4–5 in between the anterior and posterior nostrils on the side; dorsal fin originates above the level of gill opening, predorsal length is 9.3–10.9 in total length; the head is relatively large, the length is 9.3–9.8 in total length; no infraorbital pores are observed between the nostrils; teeth are numerous, small, conical and in bands on each jaw; pores are present before the gill opening 10–11 and before anus 47–48; pectoral-fin length is 2.4–2.8 in head length; predorsal vertebrae are 8–10, pre-anal vertebrae 43–47 and total vertebrae 164–169. In the maximum likelihood tree analysis for COI gene, the new species belongs to the same clade as the other congener of Cirrhimuraena chinensis and is separated from the species morphologically and genetically. 相似文献
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Lauren B. Jones Xiaoqiang Wang Jaya S. Gullapalli Daniel A. Kunz 《Biochemistry and Biophysics Reports》2021
We report the purification and characterization of a nitrilase (E.C. 3.5.5.1) (Nit11764) essential for the assimilation of cyanide as the sole nitrogen source by the cyanotroph, Pseudomonas fluorescens NCIMB 11764. Nit11764, is a member of a family of homologous proteins (nitrile_sll0784) for which the genes typically reside in a conserved seven-gene cluster known as Nit1C. The physical properties and substrate specificity of Nit11764 resemble those of Nit6803, the current reference protein for the family, and the only true nitrilase that has been crystallized. The substrate binding pocket of the two enzymes places the substrate in direct proximity to the active site nucleophile (C160) and conserved catalytic triad (Glu44, Lys126). The two enzymes exhibit a similar substrate profile, however, for Nit11764, cinnamonitrile, was found to be an even better substrate than fumaronitrile the best substrate previously identified for Nit6803. A higher affinity for cinnamonitrile (Km 1.27 mM) compared to fumaronitrile (Km 8.57 mM) is consistent with docking studies predicting a more favorable interaction with hydrophobic residues lining the binding pocket. By comparison, 3,4-dimethoxycinnamonitrile was a poorer substrate the substituted methoxyl groups apparently hindering entry into the binding pocket. in situ 1H NMR studies revealed that only one of the two nitrile substituents in the dinitrile, fumaronitrile, was attacked yielding trans-3-cyanoacrylate (plus ammonia) as a product. The essentiality of Nit11764 for cyanotrophy remains uncertain given that cyanide itself is a poor substrate and the catalytic efficiencies for even the best of nitrile substrates (~5 × 103 M?1 s?1) is less than stellar. 相似文献
10.
Altered proteolysis of amyloid precursor protein is an important determinant of pathology development in Alzheimer''s disease. Here, we describe the detection of two novel fragments of amyloid precursor protein in H4 neuroglioma cells undergoing apoptosis. Immunoreactivity of these 25–35 kDa fragments to two different amyloid precursor protein antibodies suggests that they contain the amyloid-β region and an epitope near the C-terminus of amyloid precursor protein. Generation of these fragments is associated with cleavage of caspase-3 and caspase-7, suggesting activation of these caspases. Studies in neurons undergoing DNA damage-induced apoptosis also showed similar results. Inclusion of caspase inhibitors prevented the generation of these novel fragments, suggesting that they are generated by a caspase-dependent mechanism. Molecular weight prediction and immunoreactivity of the fragments generated suggested that such fragments could not be generated by cleavage at any previously identified caspase, secretase, or calpain site on amyloid precursor protein. Bioinformatic analysis of the amino acid sequence of amyloid precursor protein revealed that fragments fitting the observed size and immunoreactivity could be generated by either cleavage at a novel, hitherto unidentified, caspase site or at a previously identified matrix metalloproteinase site in the extracellular domain. Proteolytic cleavage at any of these sites leads to a decrease in the generation of α-secretase cleaved secreted APP, which has both anti-apoptotic and neuroprotective properties, and thus may contribute to neurodegeneration in Alzheimer''s disease. 相似文献