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961.
Shuangwei Li Jochem B. Evers Wopke van der Werf Ruili Wang Zhaoli Xu Yan Guo Baoguo Li Yuntao Ma 《The Annals of applied biology》2020,177(2):195-210
Maize/soybean strip intercropping is a commonly used system throughout China with high crop yields at reduced nutrient input compared to sole maize. Maize is the taller crop, and due to its dominance in light capture over soybean in the intercrop, maize is expected to outperform maize in sole cropping. Conversely, soybean is the subordinate crop and intercropped soybean plants are expected to perform worse than sole soybean. Crop plants show plastic responses in plant architecture to their growing conditions to forage for light and avoid shading. There is little knowledge on plant architectural responses to growing conditions in simultaneous (non-relay) intercropping and their relationship to species yields. A two-year field experiment with two simultaneous maize/soybean intercropping systems with narrow and wide strips was conducted to characterise architectural traits of maize and soybean plants grown as intercrop and sole crops. Intercropped maize plants, especially those in border rows, had substantially greater leaf area, biomass and yield than maize plants in sole crops. Intercropped soybean plants, especially those in border rows, had lower leaf area, biomass and yield than sole soybean plants. Overall intercrop performance was similar to that of sole crops, with the land equivalent ratio (LER) being only slightly greater than one (1.03–1.08). Soybean displayed typical shade avoidance responses in the intercrop, such as greater internode elongation and changes in specific leaf area, but these responses could not overcome the consequences of the competition with the taller maize plants. Therefore, in contrast to relay intercrop systems, in the studied simultaneous maize/soybean system, plastic responses did not contribute to practically relevant increases in resource capture and yield at whole system (i.e., intercrop) level. 相似文献
962.
Tropical forests have been facing high rates of deforestation driven by multiple anthropogenic disturbances, with severe consequences for biodiversity. However, the understanding of such effects on functional diversity is still limited in tropical regions, especially considering different ecological groups responses. Here, we evaluated the functional responses of birds to forest loss at the threatened Brazilian Atlantic forest, considering the complete assemblage, and both forest-dependent and non-forest-dependent species. Birds were surveyed in 40 forest sites with a forest cover gradient, located in two regions showing different land use types. We tested different models to assess the responses of functional diversity indices to forest loss in these sites. Although functional diversity did not differ between regions, forest and non-forest birds showed divergent responses to forest loss. Deforested landscapes presented an increase in functional richness (SESFRic) and evenness for forest species and an increase of functional dispersion for non-forest birds. Additionally, forested landscapes harbor birds presenting lower body mass and wing length, and non-forest species with lower tarsus length. The maintenance of some functional metrics through forest loss resulted from a compensatory dynamic between forest and non-forest birds, indicating that only evaluating the complete assemblage may mask important idiosyncratic patterns of different ecological groups. Although non-forest species are relatively capable to maintain bird functional diversity in deforested landscapes, forest birds are facing a drastic ongoing collapse in these sites, representing an alarming signal for the maintenance of forest ecosystem function. 相似文献
963.
Huang Yongji Chen Hong Han Jinlei Zhang Ya Ma Shulin Yu Guangrun Wang Zonghua Wang Kai 《Chromosoma》2020,129(1):45-55
Chromosoma - Modern sugarcane cultivars are highly polyploid and derived from the hybridization of Saccharum officinarum and S. spontaneum, thus leading to singularly complex genomes. The complex... 相似文献
964.
Aleksandra Łukasiewicz Małgorzata Niśkiewicz Jacek Radwan 《Evolution; international journal of organic evolution》2020,74(8):1851-1855
Elaborate sexually selected ornaments and armaments are costly but increase the reproductive success of their bearers (usually males). It has been postulated that high-quality males can invest disproportionately more in such traits, making those traits honest signals of genetic quality. However, genes associated with such traits may have sexually antagonistic effects on fitness. Here, using a bulb mite Rhizoglyphus robini, a species in which a distinct dimorphism exists between males in the expression of a sexually selected weapon, we compare inbreeding and gender load between lines derived from armed fighters and unarmed scramblers. After four generations of sib-mating, inbreeding depression for female fitness was significantly lower in fighter-derived lines compared to scrambler-derived lines, suggesting that fighter males had significantly higher genetic quality. However, outbred females from fighter-derived lines had significantly lower fitness compared to outbred females from scrambler-derived lines, demonstrating significant gender load associated with the presence of a sexually selected male weapon. Our results imply that under outbreeding, genetic benefits of mating with bearers of elaborate sexually selected traits might be swamped by the costs of decreased fitness of female progeny due to sexually antagonistic effects. 相似文献
965.
Breast carcinoma is one of the most commonly diagnosed tumors and also one of the deadliest cancers in the female. Long noncoding RNAs (lncRNAs) are emerging as novel targets and biomarkers for breast cancer diagnosis and treatment. In this study, we aimed to study the lncRNAs associated with the outcomes in patients using the breast invasive carcinoma datasets from The Cancer Genome Atlas. The Cox proportional hazards regression model was fitted to each lncRNA. Hierarchy clustering was carried out using these survival-related lncRNAs and the log-rank test was carried out for the clustered groups. DNA methylation status was utilized to identify the lncRNAs regulated by epigenetics. Finally, the coexpressed messenger RNA with the potential lncRNAs were utilized to study the possible functions and mechanisms of lncRNAs. In total, 182 lncRNAs had an impact on the survival time of the patients with a cutoff <0.01. The patients were clustered into three groups using these survival-related genes, which performed significantly different prognosis. Two lncRNAs, which were significantly correlated with the outcomes of breast cancer and were regulated by methylation status, were obtained. These two lncRNAs were TP53TG1 and RP5-1061H20.4. We proposed that TP53TG1 was activated by the wild-type TP53 and performed an impact on the PI3Ks family by binding YBX2 in breast cancer. 相似文献
966.
Li Jiang Yanguo Qiao Zhenghui Wang Xiuzhu Ma Haichao Wang Jian Li 《Journal of cellular physiology》2020,235(1):380-393
Atherosclerosis (AS), a chronic disorder of large arteries, is the underlying pathological process of heart disease and stroke. Former researchers have found that microRNAs (miRs) are involved in the several key processes of AS. Apolipoprotein E knockout (ApoE−/−) mice fed a high-fat-diet (HFD) to establish AS model. The expression of miR-103 was characterized in the mice model. The effects of miR-103 on inflammation and endoplasmic reticulum stress (ERS) were analyzed when the expression of miR-103 was inhibited in ApoE −/− mice fed an HFD and human aortic endothelial cells (HAECs) exposed to oxidized low-density lipoprotein (ox-LDL). The relationship between miR-103 and phosphatase and tensin homolog (PTEN) was identified by luciferase activity detection and real-time quantitative polymerase chain reaction (RT-qPCR). Gain- and loss-function approaches were further applied for investigating the regulatory effects of miR-103 and PTEN on ERS. Role of MAPK signaling was then analyzed using PD98059 to block this pathway. miR-103 was highly expressed in the ApoEApoE −/− mice fed an HFD. Downregulation of miR-103 suppressed inflammation and ERS in endothelial cells isolated from ApoE −/− mice fed a HFD and ox-LDL-exposed HAECs. In addition, miR-103 can target PTEN and downregulate its expression. Overexpression of PTEN reversed the miR-103-induced activation of MAPK signaling. Moreover, PTEN upregulation or MAPK signaling inhibition ease miR-103-induced inflammation and ERS in vivo and in vitro. Thus, miR-103 depletion restrains the progression of AS through blocking PTEN-mediated MAPK signaling. 相似文献
967.
968.
Junling Ma P. van den Driessche Frederick H. Willeboordse 《Journal of mathematical biology》2013,66(1-2):75-94
An ordinary differential equation (ODE) epidemiological model for the spread of a disease that confers immunity, such as influenza, is introduced incorporating both network topology and households. Since most individuals of a susceptible population are members of a household, including the household structure as an aspect of the contact network in the population is of significant interest. Epidemic curves derived from the model are compared with those from stochastic simulations, and shown to be in excellent agreement. Expressions for disease threshold parameters of the ODE model are derived analytically and interpreted in terms of the household structure. It is shown that the inclusion of households can slow down or speed up the disease dynamics, depending on the variance of the inter-household degree distribution. This model illustrates how households (clusters) can affect disease dynamics in a complicated way. 相似文献
969.
Adolfo López-Esparza Aurelio Álvarez-Vargas Héctor M. Mora-Montes Arturo Hernández-Cervantes Ma. Del Carmen Cano-Canchola Arturo Flores-Carreón 《Archives of microbiology》2013,195(7):499-506
Sporothrix schenckii is a fungal pathogen of humans and the etiological agent of sporotrichosis. In fungi, proper protein glycosylation is usually required for normal composition of cell wall and virulence. Upon addition of precursor oligosaccharides to nascent proteins in the endoplasmic reticulum, glycans are further modified by Golgi-glycosyl transferases. In order to add sugar residues to precursor glycans, nucleotide diphosphate sugars are imported from the cytosol to the Golgi lumen, the sugar is transferred to glycans, and the resulting nucleoside diphosphate is dephosphorylated by the nucleoside diphosphatase Gda1 before returning to cytosol. Here, we isolated the open reading frame SsGDA1 from a S. schenckii genomic DNA library. In order to confirm the function of SsGda1, we performed complementation assays in a Saccharomyces cerevisiae gda1? null mutant. Our results indicated that SsGDA1 restored the nucleotide diphosphatase activity to wild-type levels and therefore is a functional ortholog of S. cerevisiae GDA1. 相似文献
970.