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81.
Rainbow lizards (Agama agama) are common in suburban areas throughout Africa, and have an opportunistic foraging strategy, with arthropods being the main prey source. In a coastal resort in southern Togo, West Africa, several individuals in a population were observed while feeding regularly upon non-natural human-made food (pizza) and showing a clear preference for a given type of food versus others that were offered (‘four cheeses’ being the preferred one). The fact that all monitored individuals fed upon a same type of pizza suggests that they may have some chemical cues attracting them.  相似文献   
82.
Triatomines display most of their activities during the night. Before sunrise, they search, select and occupy adequate shelters to stay during the photophase, avoiding exposure to diurnal predators. In this work, we first explored the interactions between individuals of the same or different species in the shelter selection process of Triatoma infestans (Klug 1834) and Rhodnius prolixus (Stål 1859). When two groups of insects (either of different nutritional status, nymphal instar or species) were released together over an experimental arena containing two identical shelters, all nymphs were distributed randomly, suggesting the absence of intra- and inters-pecific interactions. Secondly, we analysed their preferences for particular features of shelters by releasing one group of insects (either T. infestans or R. prolixus) over an arena containing two different refuges. Nymphs exhibited preferences for darker shelters with a vertical orientation of its substrate and elevated from the ground, highlighting the importance of such features in a shelter selection context. We conclude that these species disregard the presence of other individuals but evaluate certain characteristics of the shelters to choose them. This information may contribute to understanding the colonization/recolonization dynamic processes of these Chagas disease vectors.  相似文献   
83.
A new isopropyl chromone ( 1 ) and a new flavanone glucoside ( 2 ) together with eleven known compounds ( 3–13 ) were isolated from the leaves of Syzygium cerasiforme (Blume) Merr. & L.M.Perry. Their structures were elucidated as 5,7-dihydroxy-2-isopropyl-6,8-dimethyl-4H-chromen-4-one ( 1 ), 5,7-dihydroxyflavanone 7-O-β-D-(6′′-O-galloylglucopyranoside) ( 2 ), strobopinin ( 3 ), demethoxymatteucinol ( 4 ), pinocembrin-7-O-β-D-glucopyranoside ( 5 ), (2S)-hydroxynaringenin-7-O-β-D-glucopyranoside ( 6 ), afzelin ( 7 ), quercetin ( 8 ), kaplanin ( 9 ), endoperoxide G3 ( 10 ), grasshopper ( 11 ), vomifoliol ( 12 ), litseagermacrane ( 13 ) by the analysis of HR-ESI-MS, NMR, and CD spectral data. Compounds 1 , 2 , 5 , 6 and 10 inhibited NO production on LPS-activated RAW264.7 cells with IC50 values of 12.28±1.15, 8.52±1.62, 7.68±0.87, 9.67±0.57, and 6.69±0.34 μM, respectively, while the IC50 values of the other compounds ranging from 33.38±0.78 to 86.51±2.98 μM, compared to that of the positive control, NG-monomethyl-L-arginine acetate (L-NMMA) with an IC50 value of 32.50±1.00 μM.  相似文献   
84.
The current report describes the chemical investigation and biological activity of extracts produced by three fungal strains Fusarium oxysporum, Penicillium simplicissimum, and Fusarium proliferatum isolated from the roots of Piper nigrum L. growing in Vietnam. These fungi were namely determined by morphological and DNA analyses. GC/MS identification revealed that the EtOAc extracts of these fungi were associated with the presence of saturated and unsaturated fatty acids. These EtOAc extracts showed cytotoxicity towards cancer cell lines HepG2, inhibited various microbacterial organisms, especially fungus Aspergillus niger and yeast Candida albicans (the MIC values of 50–100 μg/mL). In α-glucosidase inhibitory assay, they induced the IC50 values of 1.00-2.53 μg/mL were better than positive control acarbose (169.80 μg/mL). The EtOAc extract of F. oxysporum also showed strong anti-inflammatory activity against NO production and PGE-2 level. Four major compounds linoleic acid (37.346 %), oleic acid (27.520 %), palmitic acid (25.547 %), and stearic acid (7.030 %) from the EtOAc extract of F. oxysporum were selective in molecular docking study, by which linoleic and oleic acids showed higher binding affinity towards α-glucosidase than palmitic and stearic acids. In subsequent docking assay with inducible nitric oxide synthase (iNOS), palmitic acid, oleic acid and linoleic acid could be moderate inhibitors.  相似文献   
85.
Herein, we report the design, synthesis and evaluation of novel (E)-3-(3-oxo-4-substituted-3,4-dihydro-2H-benzo[b][1,4]oxazin-6-yl)-N-hydroxypropenamides ( 4 a – i , 7 a – g ) targeting histone deacetylases. Three human cancer cell lines were used to test the cytotoxicity of the synthesized compounds (SW620, colon; PC-3, prostate; NCI−H23, lung cancer); inhibitory activity towards HDAC; anticancer activity; as well as their impact on the cell cycle and apoptosis. As a result, compounds 4 a – i bearing the alkyl substituents seemed to be less potent than the benzyl-containing compounds 7 a – g in all biological assays. Compounds 7 e – f were found to be the most active HDAC inhibitors with IC50 of 1.498±0.020 μM and 1.794±0.159 μM, respectively. In terms of cytotoxicity and anticancer assay, 7 e and 7 f also showed good activity with IC50 values in the micromolar range. In addition, the cell cycle and apoptosis of SW620 were affected by compound 7 f in almost a similar manner to that of reference compound SAHA. Docking assays were carried out for analysis the binding mode and selectivity of this compound toward 8 HDAC isoforms. Overall, our data confirmed that the inhibition of HDAC plays a pivotal role in their anticancer activity.  相似文献   
86.
The garnet-type phase Li7La3Zr2O12 (LLZO) attracts significant attention as an oxide solid electrolyte to enable safe and robust solid-state batteries (SSBs) with potentially high energy density. However, while significant progress has been made in demonstrating compatibility with Li metal, integrating LLZO into composite cathodes remains a challenge. The current perspective focuses on the critical issues that need to be addressed to achieve the ultimate goal of an all-solid-state LLZO-based battery that delivers safety, durability, and pack-level performance characteristics that are unobtainable with state-of-the-art Li-ion batteries. This perspective complements existing reviews of solid/solid interfaces with more emphasis on understanding numerous homo- and heteroionic interfaces in a pure oxide-based SSB and the various phenomena that accompany the evolution of the chemical, electrochemical, structural, morphological, and mechanical properties of those interfaces during processing and operation. Finally, the insights gained from a comprehensive literature survey of LLZO–cathode interfaces are used to guide efforts for the development of LLZO-based SSBs.  相似文献   
87.
88.
In connectivity models, land cover types are assigned cost values characterizing their resistance to species movements. Landscape genetic methods infer these values from the relationship between genetic differentiation and cost distances. The spatial heterogeneity of population sizes, and consequently genetic drift, is rarely included in this inference although it influences genetic differentiation. Similarly, migration rates and population spatial distributions potentially influence this inference. Here, we assessed the reliability of cost value inference under several migration rates, population spatial patterns and degrees of population size heterogeneity. Additionally, we assessed whether considering intra-population variables, here using gravity models, improved the inference when drift is spatially heterogeneous. We simulated several gene flow intensities between populations with varying local sizes and spatial distributions. We then fit gravity models of genetic distances as a function of (i) the ‘true’ cost distances driving simulations or alternative cost distances, and (ii) intra-population variables (population sizes, patch areas). We determined the conditions making the identification of the ‘true’ costs possible and assessed the contribution of intra-population variables to this objective. Overall, the inference ranked cost scenarios reliably in terms of similarity with the ‘true’ scenario (cost distance Mantel correlations), but this ‘true’ scenario rarely provided the best model goodness of fit. Ranking inaccuracies and failures to identify the ‘true’ scenario were more pronounced when migration was very restricted (<4 dispersal events/generation), population sizes were most heterogeneous and some populations were spatially aggregated. In these situations, considering intra-population variables helps identify cost scenarios reliably, thereby improving cost value inference from genetic data.  相似文献   
89.
The burgeoning cellulosic ethanol industry necessitates advancements in enzymatic saccharification, effective pretreatments for lignin removal, and the cultivation of crops more amenable to saccharification. Studies have demonstrated that natural inhibitors of lignin biosynthesis can enhance the saccharification of lignocellulose, even in tissues generated several months post-treatment. In this study, we applied daidzin (a competitive inhibitor of coniferaldehyde dehydrogenase), piperonylic acid (a quasi-irreversible inhibitor of cinnamate 4-hydroxylase), and methylenedioxy cinnamic acid (a competitive inhibitor of 4-coenzyme A ligase) to 60-day-old crops of two conventional Brazilian sugarcane cultivars and two energy cane clones, bred specifically for enhanced biomass production. The resultant biomasses were evaluated for lignin content and enzymatic saccharification efficiency without additional lignin-removal pretreatments. The treatments amplified the production of fermentable sugars in both the sugarcane cultivars and energy cane clones. The most successful results softened the most recalcitrant lignocellulose to the level of the least recalcitrant of the biomasses tested. Interestingly, the softest material became even more susceptible to saccharification.  相似文献   
90.
1. Quantitative cytophotometric analysis of the interphase cells of a rapidly proliferating differentiated tissue such as liver of new born rat, indicates that these cells can be separated into two groups on the basis of their staining characteristics after methanol fixation. 2. These groups are thought to correspond to two stages of interphase. The first, called "autosynthetic interphase," comprises cells which are duplicating chromosomal material in preparation for mitosis, and shows parallel increases in the methyl green and Feulgen staining of DNA and the fast green staining of histone from the diploid (2 C) to double these values (4 C). 3. The second group is designated the "heterosynthetic interphase," during which the cell ceases proliferating and functions in a manner commensurate with its state of differentiation. In this stage Feulgen staining indicates the diploid chromosomal complement, but there is a decreased capacity of the DNA to bind methyl green and of the histone to bind fast green. 4. The difference between the methyl green binding of the heterosynthetic and autosynthetic 2 C cells is due to the presence of a protein in the former which presumably inhibits staining by competing with the dye for binding sites on the DNA. The effect of this inhibition can be removed by extracting the protein, or by blocking the protein basic groups. 5. The decreased fast green staining of histone in the heterosynthetic cells can be minimized by prolonged fixation with formaldehyde. It is thought to stem either from a similar type of inhibition, or from an increased susceptibility of the histone to loss from the cell during this stage. 6. While histone inhibits methyl green staining of DNA in all cells, the differences between the staining properties of the autosynthetic and heterosynthetic interphase cells are believed to be due to another protein, whose properties appear similar to those of the chromosomal "residual protein." It is concluded that a complex of DNA and residual protein existing during the heterosynthetic interphase is dissociated during the autosynthetic interphase.  相似文献   
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