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The global abundance of Spot-billed Duck (Anas zonorhyncha) has declined dramatically in recent decades. Ecological information of its wild populations, particularly regarding nest site selection, is scant. We studied the nest site selection and breeding ecology of this duck in Caohai National Nature Reserve, its southernmost breeding site in the Guizhou Province of China. The aquatic vegetation of Caohai is composed of 2 different landscapes with small patches (in Site A) or large patches (in Site B). We studied the habitat preferences of breeding Spot-billed Ducks at 3 spatial scales: landscape, patch, and nest site. In total, we surveyed 413 patches during the breeding seasons of 2014 2016 (298 in Site A and 115 in Site B). We found no nests in Site A, but surveyed 88 patches with 254 nests and 27 patches without nests in Site B. Unlike the open-cup nests known from other breeding localities, the nests of the Spot-billed Duck in Caohai were dome-like structures with a lateral entrance. Patches with nests were significantly larger than patches without nests in total area, circumference, and shape index. In Site B, a negative binomial regression showed that the number of nests was positively correlated with sedge vegetation within the patch area. The reduced model from a binary logistic regression indicated that the total vegetation cover and the distance to bank had positive impacts on nest site selection of this duck in Caohai, but water depth had a negative influence. Our study suggests good concealment is a necessity for the Spot-billed Duck to construct nests in Caohai. Our survey using infrared cameras in 2021 did not record male parents participating in incubation (n = 47 cameras). The mean mass of eggs (46.91 [+ or -] 0.36 g) and clutch size (8.48 [+ or -] 0.08 eggs) values were lower than those reported for the Xianghai National Nature Reserve, a breeding stronghold for the Spot-billed Duck in northeastern China. The nest success rate in Caohai (nests where at least 1 egg hatched) was 40.4% (n = 47 nests) and the hatching success rate was 91.4% (n = 134 eggs from 19 successful nests). Maintaining the emergent hydrophyte vegetation is the primary means to conserve the nesting habitat of the Spot-billed Duck in Caohai and it is necessary to strictly enforce the law against human disturbance. Received 18 October 2021. Accepted 3 October 2022. Key words: alpine wetland ecosystem, breeding behavior, environmental factors, habitat preference, multiple spatial scales., The Spot-billed Duck (Anas zonorhyncha) has a broad geographic distribution, including China, Japan, Democratic People's Republic of Korea, Republic of Korea, Mongolia, eastern Russia, and Bhutan (IUCN 2022). The Spot-billed [...]

Abstract The scaffold protein IRS-1 is an essential node in insulin/IGF signaling. It has long been recognized that the stability of IRS-1 is dependent on its endomembrane targeting. However, how IRS-1 targets the intracellular membrane, and what type of intracellular membrane is actually targeted, remains poorly understood. Here, we found that the phase separation-mediated IRS-1 puncta attached to endoplasmic reticulum (ER). VAPB, an ER-anchored protein that mediates tethers between ER and membranes of other organelles, was identified as a direct interacting partner of IRS-1. VAPB mainly binds active IRS-1 because IGF-1 enhanced the VAPB-IRS-1 association and replacing of the nine tyrosine residues of YXXM motifs disrupted the VAPB-IRS-1 association. We further delineated that the Y745 and Y746 residues in the FFAT-like motif of IRS-1 mediated the association with VAPB. Notably, VAPB targeted IRS-1 to the ER and subsequently maintained its stability. Consistently, ablation of VAPB in mice led to downregulation of IRS-1, suppression of insulin signaling, and glucose intolerance. The amyotrophic lateral sclerosis (ALS)-derived VAPB P56S mutant also impaired IRS-1 stability by interfering with the ER-tethering of IRS-1. Our findings thus revealed a previously unappreciated condensate-membrane contact (CMC), by which VAPB stabilizes the membraneless IRS-1 signalosome through targeting it to ER membrane.

Abstract As a critical node for insulin/IGF signaling, insulin receptor substrate 1 (IRS-1) is essential for metabolic regulation. A long and unstructured C-terminal region of IRS-1 recruits downstream effectors for promoting insulin/IGF signals. However, the underlying molecular basis for this remains elusive. Here, we found that the C-terminus of IRS-1 undergoes liquid-liquid phase separation (LLPS). Both electrostatic and hydrophobic interactions were seen to drive IRS-1 LLPS. Self-association of IRS-1, which was mainly mediated by the 301–600 region, drives IRS-1 LLPS to form insulin/IGF-1 signalosomes. Moreover, tyrosine residues of YXXM motifs, which recruit downstream effectors, also contributed to IRS-1 self-association and LLPS. Impairment of IRS-1 LLPS attenuated its positive effects on insulin/IGF-1 signaling. The metabolic disease-associated G972R mutation impaired the self-association and LLPS of IRS-1. Our findings delineate a mechanism in which LLPS of IRS-1-mediated signalosomes serves as an organizing center for insulin/IGF-1 signaling and implicate the role of aberrant IRS-1 LLPS in metabolic diseases.

Abstract Background This study explored the relationships between the low−/high-density lipoprotein cholesterol ratio (LDL-C/HDL-C) and other clinical indicators and ischaemic stroke (IS) in patients with non-valvular atrial fibrillation (NVAF) in Xinjiang. The findings could provide a theoretical and therapeutic basis for NVAF patients. Methods NVAF patients who were admitted to 10 medical centres across Xinjiang were divided into stroke (798 patients) and control (2671 patients) groups according to the occurrence of first acute IS. Univariate and multivariate logistic regression analysis were used to examine the independent risk factors for IS in NVAF patients. Factor analysis and principal component regression analysis were used to analyse the main factors influencing IS. Receiver operating characteristic (ROC) curve analysis was used to evaluate the discriminatory ability of LDL-C/HDL-C for predicting the occurrence of IS. Results The stroke group had an average age of 71.64 ± 9.96 years and included 305 females (38.22%). The control group had a mean age of 67.30 ± 12.01 years and included 825 females (30.89%). Multivariate logistic regression showed that the risk of IS in the highest LDL-C/HDL-C quartile (≥2.73) was 16.23-fold that of the lowest quartile ( 1.22, smoking, BMI ≥24 kg/m2 and CHA2DS2-VASc score were independent risk factors for IS in NVAF patients; LDL-C/HDL-C was the main risk factor.

The perishable nature of most agricultural produce and the concomitant need for effective marketing outlets carries along huge economic consequences, especially in developing countries like Ghana. This study examines the determinants of profit in tomato marketing in the Ashanti Region of Ghana. Cross-sectional data collected from a random sample of 200 tomato marketers consisting of 100 wholesalers and 100 retailers were analyzed using descriptive statistics and the multiple linear regression technique of the ordinary least squares. The results show that wholesalers have a higher margin of 99.7 percent, while the retailers have a margin of 75.4 percent. Labour cost, purchase price, transportation cost and selling price run through all the estimated regressions as determinants of marketing profit. The effects of these variables on marketing profit could raise public concern since they have implications on prices received by tomato producers and those paid by final consumers and therefore there is the need for the government to devise policies aimed at stabilizing the local currency.The results also call for policy efforts to completely eliminate illiteracy among tomato traders in Ghana especially in the Ashanti Region. Policies that could enable the retailers to increase their scale of operations are also advocated. Future researchers may also estimate the exact point in the age variable at which retail profit declines and possible antecedents.

Tumor-Treating Fields (TTFields) use intermediate-frequency and low-intensity electric fields to inhibit tumor cells. However, their mechanisms are still not well understood. This article reviews their key antitumor mechanisms at the cellular and molecular levels, including inhibition of proliferation, induction of death, disturbance of migration, and activation of the immune system. The multifaceted biological effects in combination with other cancer treatments are also summarized. The deep insight into their mechanism will help develop more potential antitumor treatments., (© 2024. The Author(s), under exclusive licence to Federación de Sociedades Españolas de Oncología (FESEO).)

Understanding how nutrient addition affects the tree growth is critical for assessing forest ecosystem function and processes, especially in the context of increased nitrogen (N) and phosphorus (P) deposition. Subtropical forests are often considered N-rich and P-poor ecosystems, but few existing studies follow the traditional "P limitation" paradigm, possibly due to differences in nutrient requirements among trees of different size classes. We conducted a three-year fertilization experiment with four treatments (Control, N-treatment, P-treatment, and NP-treatment). We measured soil nutrient availability, leaf stoichiometry, and relative growth rate (RGR) of trees across three size classes (small, medium and large) in 64 plots. We found that N and NP-treatments increased the RGR of large trees. P-treatment increased the RGR of small trees. RGR was mainly affected by N addition, the total effect of P addition was only 10 % of that of N addition. The effect of nutrient addition on RGR was mainly regulated by leaf stoichiometry. This study reveals that nutrient limitation is size dependent, indicating that continuous unbalanced N and P deposition will inhibit the growth of small trees and increase the instability of subtropical forest stand structure, but may improve the carbon sink function of large trees., Competing Interests: Declaration of competing interest The author declare that they have no conflict of interests., (Copyright © 2024 Elsevier B.V. All rights reserved.)

The Convention on Biological Diversity seeks to conserve at least 30% of global land and water areas by 2030, which is a challenge but also an opportunity to better preserve biodiversity, including flowering plants (angiosperms). Herein, we compiled a large database on distributions of over 300,000 angiosperm species and the key functional traits of 67,024 species. Using this database, we constructed biodiversity-environment models to predict global patterns of taxonomic, phylogenetic, and functional diversity in terrestrial angiosperms and provide a comprehensive mapping of the three diversity facets. We further evaluated the current protection status of the biodiversity centers of these diversity facets. Our results showed that geographical patterns of the three facets of plant diversity exhibited substantial spatial mismatches and nonoverlapping conservation priorities. Idiosyncratic centers of functional diversity, particularly of herbaceous species, were primarily distributed in temperate regions and under weaker protection compared with other biodiversity centers of taxonomic and phylogenetic facets. Our global assessment of multifaceted biodiversity patterns and centers highlights the insufficiency and unbalanced conservation among the three diversity facets and the two growth forms (woody vs. herbaceous), thus providing directions for guiding the future conservation of global plant diversity., (© 2024. Science China Press.)