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81.
2D layer‐structured materials are considered a promising candidate as a coupling material in lithium sulfur batteries (LSBs) due to their high surface‐volume ratio and abundant active binding sites, which can efficiently mitigate shuttling of soluble polysulfides. Herein, an electrochemical Li intercalation and exfoliation strategy is used to prepare 2D Sb2S3 nanosheets (SSNSs), which are incorporated onto a separator in LSBs as a new 2D coupling material for the first time. The cells containing a rationally designed separator which is coated with an SSNS/carbon nanotube (CNT) coupling layer deliver a much improved specific capacity with a remarkable 0.05% decay rate for over 200 cycles at a current density of 2 C. The capability of the SSNSs to entrap polysulfides through their favorable interfacial functionality and the high electrical conductivity of the CNT network facilitates recycling of active materials. The first‐principle calculations verify the important roles of SSNSs, which demonstrate ideal binding strengths (1.33–2.14 eV) to entrap Li2Sx as well as a low‐energy barrier (189 meV) for Li diffusion. These findings offer new insights into discovering novel coupling layers for high‐performance LSBs and shed new light on the application of 2D layer‐structured materials in energy storage systems.  相似文献   
82.
The structure of isomartynoside, a new phenylpropanoid glycoside, isolated along with the known martynoside from Galeopsis pubescens, has been elucidated on the basis of chemical and spectral data as 3-hydroxy-4-methoxy-β-phenylethoxy-O-α-L-rhamnopyranosyl-(1 → 3)-6-O-feruloyl-β-D-glucopyranoside.  相似文献   
83.
In tritrophic interactions between cucumber plants, the cucumber moth Diaphania indica Saunders (Lepidoptera: Crambidae) and a larval parasitoid Apanteles taragamae Viereck (Hymenoptera: Braconidae), female A. taragamae may use herbivore-induced plant volatiles (HIPVs) to locate their host. However, the specific compound or blend of chemicals attracting A. taragamae remains unknown. In this study, differences in volatiles released from uninfested, mechanically damaged and host-infested cucumber plants were examined by the headspace volatile collection method. Responses of the larval parasitoid A. taragamae to the volatile extracts were examined in a four-arm olfactometer. We also investigated the attraction of female A. taragamae to a single compound identified as an HIPV from host-infested cucumber plants. Parasitoids discriminated between the volatiles from uninfested, host-infested and mechanically damaged plants. Chemical analysis of headspace volatiles from host-infested cucumber plants showed that (E,E)-α-farnesene was released as a major component (73.1%). When (E,E)-α-farnesene was tested alone in the range of 1.7–170?ng, female parasitoids responded to 17?ng only. Therefore, tritrophic interactions between A. taragamae and D. indica appear to be partly mediated by (E,E)-α-farnesene.  相似文献   
84.
Endophytes can serve as plant growth promoters as they secret a vast array of phytohormones to support host plants. Keeping the growth promoting activity of the endophytes in view, two endophytic fungi, Asprgillus fumigatus TS1 and Fusarium proliferatum BRL1 have been isolated from the roots of Oxalis corniculata. The isolates have been screened initially for growth promoting activities, including siderophores activity, phosphate solubilization, and secreation of indole acetic acid and gibberellins. Further, the isolates have assayed for the ability to promote the growth of mutant rice Waito-C. The plants associated with TS1 and BRL1 have shown higher chlorophyll content, root-shoot length, and biomass production. The growth promoting activity of the endophytes can be attributed to the various types of GAs and IAA that have been observed in the culture filtrates of the endophytes by the Gas chromatography/mass spectrometry (GC/MS). The GC/MS analysis revealed the presence of different gibberellins concentrations (ng/ml) in TS1 and BRL1 culture filtrate, i.e. GA1 (0.091?±?0.009, 0.392?±?0.007), GA3 (0.324?±?0.077, 0.089?±?0.0007) and GA7 (0.023?±?0.002, 0.492?±?0.005), respectively. Besides, a significant up regulation of plant endogenous GA1 (12.443?±?0.454 and 15.434?±?0.245) has been obsereved in TS1 and BRL1 associated plants compared to the control. Moreover, semi quantitative RT-PCR has confirmed the presence/invovment of GA pathways genes (P50–1, P450–3, P450–4, ggs2, and des). The results conclude that the endophytes isolated in this study can ably synthesize bioactive compounds, which play an important role in plant growth promotion.  相似文献   
85.
Solid-state fermentation (SSF) is a bioprocess that doesn’t need an excess of free water, and it offers potential benefits for microbial cultivation for bioprocesses and product development. In comparing the antibiotic production, few detailed reports could be found with lipolytic enzyme production by Streptomycetes in SSF. Taking this knowledge into consideration, we prefer to purify Actinomycetes species as a new source for lipase production. The lipase-producing strain Streptomyces sp. TEM 33 was isolated from soil and lipase production was managed by solid-state fermentation (SSF) in comparison with submerged fermentation (SmF). Bioprocess-affecting factors like initial moisture content, incubation time, and various carbon and nitrogen additives and the other enzymes secreted into the media were optimized. Lipase activity was measured as 1.74 ± 0.0005 U/g dry substrate (gds) by the p-nitrophenylpalmitate (pNPP) method on day 6 of fermentation with 71.43% final substrate moisture content. In order to understand the metabolic priority in SSF, cellulase and xylanase activity of Streptomyces sp. TEM33 was also measured. The microorganism degrades the wheat bran to its usable form by excreting cellulases and xylanases; then it secretes the lipase that is necessary for degrading the oil in the medium.  相似文献   
86.
Methoprene (an analogue of juvenile hormone) application and feeding on a protein diet is known to enhance male melon fly, Bactrocera cucurbitae Coquillett (Diptera: Tephritidae), mating success. In this study, we investigated the effect of these treatments on male B. cucurbitae's ability to inhibit female remating. While 14-d-old females were fed on protein diet, 6-d-old males were exposed to one of the following treatments: (i) topical application of methoprene and fed on a protein diet; (ii) no methoprene but fed on a protein diet; (iii) methoprene and sugar-fed only; and (iv) sugar-fed, 14-d-old males acted as controls. Treatments had no effect on a male's ability to depress the female remating receptivity in comparison to the control. Females mated with protein-deprived males showed higher remating receptivity than females first mated with protein-fed males. Methoprene and protein diet interaction had a positive effect on male mating success during the first and second mating of females. Significantly more females first mated with sugar-fed males remated with protein-fed males and females first mated with methoprene treated and protein-fed males were more likely to remate with similarly treated males. Females mating latency (time to start mating) was significantly shorter with protein-fed males, and mating duration was significantly longer with protein-fed males compared with protein-deprived males. These results are discussed in the context of methoprene and/or dietary protein as prerelease treatment of sterile males in area-wide control of melon fly integrating the sterile insect technique (SIT).  相似文献   
87.
Plant growth promoting endophytic bacteria have been identified as potential growth regulators of crops. Endophytic bacterium, Sphingomonas sp. LK11, was isolated from the leaves of Tephrosia apollinea. The pure culture of Sphingomonas sp. LK11 was subjected to advance chromatographic and spectroscopic techniques to extract and isolate gibberellins (GAs). Deuterated standards of [17, 17-2H2]-GA4, [17, 17-2H2]-GA9 and [17, 17-2H2]-GA20 were used to quantify the bacterial GAs. The analysis of the culture broth of Sphingomonas sp. LK11 revealed the existence of physiologically active gibberellins (GA4: 2.97 ± 0.11 ng/ml) and inactive GA9 (0.98 ± 0.15 ng/ml) and GA20 (2.41 ± 0.23). The endophyte also produced indole acetic acid (11.23 ± 0.93 μM/ml). Tomato plants inoculated with endophytic Sphingomonas sp. LK11 showed significantly increased growth attributes (shoot length, chlorophyll contents, shoot, and root dry weights) compared to the control. This indicated that such phyto-hormones-producing strains could help in increasing crop growth.  相似文献   
88.
Methoprene (an analogue of juvenile hormone) application and feeding on a protein diet is known to enhance male melon fly, Bactrocera cucurbitae Coquillett (Diptera: Tephritidae), mating success. In this study, we investigated the effect of these treatments on male B. cucurbitae's ability to inhibit female remating. While 14‐d‐old females were fed on protein diet, 6‐d‐old males were exposed to one of the following treatments: (i) topical application of methoprene and fed on a protein diet; (ii) no methoprene but fed on a protein diet; (iii) methoprene and sugar‐fed only; and (iv) sugar‐fed, 14‐d‐old males acted as controls. Treatments had no effect on a male's ability to depress the female remating receptivity in comparison to the control. Females mated with protein‐deprived males showed higher remating receptivity than females first mated with protein‐fed males. Methoprene and protein diet interaction had a positive effect on male mating success during the first and second mating of females. Significantly more females first mated with sugar‐fed males remated with protein‐fed males and females first mated with methoprene treated and protein‐fed males were more likely to remate with similarly treated males. Females mating latency (time to start mating) was significantly shorter with protein‐fed males, and mating duration was significantly longer with protein‐fed males compared with protein‐deprived males. These results are discussed in the context of methoprene and/or dietary protein as prerelease treatment of sterile males in area‐wide control of melon fly integrating the sterile insect technique (SIT).  相似文献   
89.
Scabies and pediculosis are ubiquitous, contagious, and debilitating parasitic dermatoses. The tendency of high prevalence of pediculosis and scabies among school and preschool age children has prompted us to conduct a head louse and scabies prevalence survey among preschool nursery children in our district. A school-based, crosssectional study was performed, with 1,134 children chosen for evaluation. All cases were evaluated by physical examination and a detailed, structured questionnaire. The infestation was found in 14 (1.2%) of 1,134 children; 9 (0.8%) with pediculosis capitis and 5 (0.4%) with scabies. We found that infestations were more frequent in children with mothers whose education levels were low. This indicates the necessity of an improvement in the economic and sociocultural status of the community and the promotion of hygiene concepts and practices in order to improve health of preschool age children.  相似文献   
90.
Baibutoside (5), a new cycloartane-type triterpene glycoside, has been isolated from the roots of Astragalus baibutensis along with four known glycosides, acetylastragaloside I (1), and astragalosides I, II, and IV (2-4, resp.). The structure elucidation of the compounds were achieved by a combination of one- and two-dimensional NMR techniques (DQF-COSY, HSQC, HMBC, and ROESY), and mass spectrometry (ESI-MS), where all the compounds were shown to have cycloastragenol (=(20R,24S)-3beta,6alpha,16beta,25-tetrahydroxy-20,24-epoxy-9,19-cyclolanostane) as aglycone. All compounds were tested for in vitro antiprotozoal activity. Compounds 1-4 displayed notable activity vs. Trypanosoma brucei rhodesiense, with acetylastragaloside I (1) being the most potent (IC50 9.5 microg/ml). Acetylastragaloside I (1) was also lethal to T. cruzi (IC50 5.0 microg/ml), and it is the first cycloartane-type triterpene with remarkable trypanocidal activity against both T. brucei rhodesiense and T. cruzi. However, it exhibits some cytotoxicity on mammalian cells.  相似文献   
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