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1.
In a cold store, the house rat, Rattus rattus, damaged fruits and vegetables, including potato (Solanum nigrum), cauliflower (Brassica oleracea), sweet orange (Citrus sinenis), mango (Mangifera indica), grape (Vitis vinifera) and apple (Malus pumilla). Sweet orange and grape were damaged most, and damage to potatoes was relatively low. Packaging materials like jute bags and cardboard boxes were more frequently damaged by rats than were wooden boxes. Rats avoided metallic bait containers because they were made of good conductors of heat. Trapping of rats conducted using insulated traps resulted in the control success of 83–94%. 相似文献
2.
There was little release of extractable SO4-S during four weeks from CS2 applied by injecting into two S-deficient soils. In this incubation experiment, the rate of CS2 was 30 μg S g−, placement was injection at 9 cm depth, soil temperature was 20°C, and soil moisture tension was 33 kPa. The yield of barley
forage after seven weeks in the greenhouse showed only small increases from 10 or 30 μg S g−1 of CS2 as compared to Na2SO4, on the two soils.
While CS2 supplied little plant available S in the short term, it was an effective inhibitor of nitrification. In the laboratory, or
in the field, the injection of CS2 (with N fertilizers) at a point 9 cm into the soils either stopped or reduced nitrification. In one laboratory experiment,
35 μg of CS2 g−1 of soil with urea reduced nitrification for at least four weeks; and in another experiment 20 μg of CS2 g−1 of soil with aqua NH3 nearly or completely inhibited nitrification at 20 days. In two field experiments, 3 and 12 μg of CS2 g−1 of soil (or 6 and 24 kg ha−1) with aqua NH3 inhibited nitrification from October to the subsequent May. In addition, CS2 reduced the amount of ammonium produced from the soil N, both in these two field experiments and in the laboratory experiments.
That is to say, CS2 injected at a point, inhibited both nitrification and ammonification.
In other field experiments, CS2 at a rate of 10 kg ha−1 was injected in bands 9 cm deep with urea in October, and by May there was still reduced nitrification. Less than half of
the fall-applied urea alone was recovered as mineral N, but with the application of CS2 the recovery was increased to three-quarters.
The yield and N uptake of barley grain was increased where fall-applied banded urea or aqua NH3 received banded CS2, (NH4)2CS3, or K2CS3. The average increase in yield from fall-applied fertilizer, from inhibitor with fall-applied fertilizer, and from spring-applied
fertilizer was 800, 1370, and 1900 kg ha−1, respectively. In the same order, the apparent % recovery of fertilizer N in grain was 24, 42, and 60. 相似文献
3.
Huiting Ho Harmeet Singh Sophea Heng Tracy L. Nero Sarah Paule Michael W. Parker Alan T. Johnson Guan-Sheng Jiao Guiying Nie 《PloS one》2013,8(12)
Uterine proprotein convertase (PC) 6 plays a critical role in embryo implantation and is pivotal for pregnancy establishment. Inhibition of PC6 may provide a novel approach for the development of non-hormonal and female-controlled contraceptives. We investigated a class of five synthetic non-peptidic small molecule compounds that were previously reported as potent inhibitors of furin, another PC member. We examined (i) the potency of these compounds in inhibiting PC6 activity in vitro; (ii) their binding modes in the PC6 active site in silico; (iii) their efficacy in inhibiting PC6-dependent cellular processes essential for embryo implantation using human cell-based models. All five compounds showed potent inhibition of PC6 activity in vitro, and in silico docking demonstrated that these inhibitors could adopt a similar binding mode in the PC6 active site. However, when these compounds were tested for their inhibition of decidualization of primary human endometrial stromal cells, a PC6-dependent cellular process critical for embryo implantation, only one (compound 1o) showed potent inhibition. The lack of activity in the cell-based assay may reflect the inability of the compounds to penetrate the cell membrane. Because compound''s lipophilicity is linked to cell penetration, a measurement of lipophilicity (logP) was calculated for each compound. Compound 1o is unique as it appears the most lipophilic among the five compounds. Compound 1o also inhibited another crucial PC6-dependent process, the attachment of human trophoblast spheroids to endometrial epithelial cells (a model for human embryo attachment). We thus identified compound 1o as a potent small molecule PC6 inhibitor with pharmaceutical potential to inhibit embryo implantation. Our findings also highlight that human cell-based functional models are vital to complement the biochemical and in silico analyses in the selection of promising drug candidates. Further investigations for compound 1o are warranted in animal models to test its utility as an implantation-inhibiting contraceptive drug. 相似文献
4.
Nonalcoholic steatohepatitis (NASH) is a lipotoxic disease wherein activation of endoplasmic reticulum (ER) stress response and macrophage-mediated hepatic inflammation are key pathogenic features. However, the lipid mediators linking these two observations remain elusive. We postulated that ER stress-regulated release of pro-inflammatory extracellular vesicles (EVs) from lipotoxic hepatocytes may be this link. EVs were isolated from cell culture supernatants of hepatocytes treated with palmitate (PA) to induce lipotoxic ER stress, characterized by immunofluorescence, Western blotting, electron microscopy, and nanoparticle tracking analysis. Sphingolipids were measured by tandem mass spectrometry. EVs were employed in macrophage chemotaxis assays. PA induced significant EV release. Because PA activates ER stress, we used KO hepatocytes to demonstrate that PA-induced EV release was mediated by inositol requiring enzyme 1α (IRE1α)/X-box binding protein-1. PA-induced EVs were enriched in C16:0 ceramide in an IRE1α-dependent manner, and activated macrophage chemotaxis via formation of sphingosine-1-phosphate (S1P) from C16:0 ceramide. This chemotaxis was blocked by sphingosine kinase inhibitors and S1P receptor inhibitors. Lastly, elevated circulating EVs in experimental and human NASH demonstrated increased C16:0 ceramide. PA induces C16:0 ceramide-enriched EV release in an IRE1α-dependent manner. The ceramide metabolite, S1P, activates macrophage chemotaxis, a potential mechanism for the recruitment of macrophages to the liver under lipotoxic conditions. 相似文献
5.
C.?A.?L.?Dahlsj?Email author C.?L.?Parr Y.?Malhi P.?Meir P.?Eggleton 《Insectes Sociaux》2015,62(2):141-150
Termites are frequently dominant invertebrate decomposers and bioturbators in lowland tropical forests and therefore strongly influence ecosystem processes favouring soil stability, porosity and nutrient retention. In this study, we provide the first spatially replicated dataset on termite assemblage composition, abundance and biomass in a Peruvian rainforest by sampling six separate plots. In addition, two alternative sampling methods (transect method-TM and quadrat method-QM), providing termite species density data, were compared among the plots. The relationships between a range of environmental and spatial variables and species composition were examined using canonical correspondence analysis variation partitioning. We found that the TM captured a higher proportion of the known species in the site (82 %) compared with the QM (66 %). In addition, 56 % of the species sampled by TM were common between the plots while only 18 % of species overlapped using the QM. The QM may therefore potentially have undersampled the species pool. Environmental variables were shown to explain a larger proportion of the species patterns than the spatial variables with elevation, soil temperature and distance to the river being the most important. We discuss the impacts of the environmental and spatial variables on termite species composition. 相似文献
6.
7.
Ann Carla Staver Paulo M. Brando Jos Barlow Douglas C. Morton C.E. Timothy Paine Yadvinder Malhi Alejandro Araujo Murakami Jhon del Aguila Pasquel 《Ecology letters》2020,23(1):99-106
Understory fires represent an accelerating threat to Amazonian tropical forests and can, during drought, affect larger areas than deforestation itself. These fires kill trees at rates varying from < 10 to c. 90% depending on fire intensity, forest disturbance history and tree functional traits. Here, we examine variation in bark thickness across the Amazon. Bark can protect trees from fires, but it is often assumed to be consistently thin across tropical forests. Here, we show that investment in bark varies, with thicker bark in dry forests and thinner in wetter forests. We also show that thinner bark translated into higher fire‐driven tree mortality in wetter forests, with between 0.67 and 5.86 gigatonnes CO2 lost in Amazon understory fires between 2001 and 2010. Trait‐enabled global vegetation models that explicitly include variation in bark thickness are likely to improve the predictions of fire effects on carbon cycling in tropical forests. 相似文献
8.
Lambers Hans Wright Ian J. Guilherme Pereira Caio Bellingham Peter J. Bentley Lisa Patrick Boonman Alex Cernusak Lucas A. Foulds William Gleason Sean M. Gray Emma F. Hayes Patrick E. Kooyman Robert M. Malhi Yadvinder Richardson Sarah J. Shane Michael W. Staudinger Christiana Stock William D. Swarts Nigel D. Turner Benjamin L. Turner John Veneklaas Erik J. Wasaki Jun Westoby Mark Xu Yanggui 《Plant and Soil》2021,461(1-2):43-61
Plant and Soil - Root-released carboxylates enhance the availability of manganese (Mn), which enters roots through transporters with low substrate specificity. Leaf Mn concentration ([Mn]) has been... 相似文献
9.
Mannan Ashi Garg Nikhil Singh Thakur Gurjeet Kang Harmeet Kaur 《Neurochemical research》2021,46(11):2800-2831
Neurochemical Research - Cerebral ischemic injury is a leading cause of death and long-term disability throughout the world. Peroxisome proliferator-activated receptor gamma (PPAR-?) is a... 相似文献
10.
Erin S. Luetkemeier Ripan S. Malhi Jonathan E. Beever Lawrence B. Schook 《Immunogenetics》2009,61(2):119-129
The major histocompatibility complex (MHC) is an immunological gene-dense region of high diversity in mammalian species. Sus scrofa was domesticated by at least six independent events over Eurasia during the Holocene period. It has been hypothesized that
the level and distribution of MHC variation in pig populations reflect genetic selection and environmental influences. In
an effort to define the complexity of MHC polymorphisms and the role of selection in the generation of class II gene diversity
(DQB, DRB1, and pseudogene ΨDRB3), DNA from globally distributed unrelated domestic pigs of European and Asian origins and
a Suidae out-group was analyzed. The number of pseudogene alleles identified (ΨDRB3 33) was greater than those found in the
expressed genes (DQB 20 and DRB1 23) but the level of observed heterozygosity (ΨDRB3 0.452, DQB 0.732, and DRB1 0.767) and
sequence diversity (ΨDRB3 0.029, DQB 0.062, and DRB1 0.074) were significantly lower in the pseudogene, respectively. The
substitution ratios reflected an excess of d
N (DQB 1.476, DRB1 1.724, and ΨDRB3 0.508) and the persistence of expressed gene alleles suggesting the influence of balancing
selection, while the pseudogene was undergoing purifying selection. The lack of a clear MHC phylogeographic tree, coupled
with close genetic distances observed between the European and Asian populations (DQB 0.047 and DRB1 0.063) suggested that
unlike observations using mtDNA, the MHC diversity lacks phylogeographic structure and appears to be globally uniform. Taken
together, these results suggest that, despite regional differences in selective breeding and environments, no skewing of MHC
diversity has occurred.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献