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991.
Sussy Munialo A. Sigrun Dahlin Cecilia Onyango M. W. Oluoch‐Kosura Hkan Marstorp Ingrid
born 《Food and Energy Security》2020,9(1)
The solution to reducing existing yield gaps on smallholder farms lies in understanding factors limiting yield in areas with agricultural intensification potential. This study applied an integrated analysis approach comprising Classification and Regression Tree (CART), generalized linear mixed model (GLMM), and factor analysis (FA), to explain soil and management‐related factors influencing maize yield gaps, in order to enhance yields. The study was conducted in Mukuyu and Shikomoli in western Kenya, sites with, respectively, high and low agroecological potential regarding soil fertility. Maize yield gaps were quantified by comparing yields on the 90th percentile of farms to yields determined in 189 fields on 70 randomly sampled smallholdings. Soil and management‐related factors were determined at early and late maize development stages. Maize yield on the 90th percentile of farms in Mukuyu and Shikomoli was 5.1 and 4.8 t/ha, respectively, and the average yield gap was 1.8 and 2.6 t/ha, representing 35% and 54% unachieved yield for Mukuyu and Shikomoli, respectively. In FA, soil was revealed to be the main factor influencing maize yield gaps at both sites, rather than management‐related variables. The CART method identified maize density, chlorophyll values, maize height, and depth to compact layer as consistent factors affecting yield at both sites, while GLMM identified soil texture (silt content) as important. According to CART, weed cover at early stages and maize density at late stages were the most limiting factor in maize production in Mukuyu and Shikomoli, respectively. Generalized linear mixed model analysis identified agroecology‐specific factors influencing maize yield gaps as soil‐available phosphorus and zinc, plus weed pressure at early maize stages in Mukuyu, and plus soil cation exchange capacity and exchangeable magnesium in Shikomoli. Through an integrated approach, it was possible to identify both consistent and agroecology‐specific factors limiting crop yields. This can increase the applicability of the findings to smallholder farms. 相似文献
992.
We have investigated the magnetic properties and the 155Gd Mössbauer spectra of the ThCr2Si2-type compounds GdNi2Sb2, GdCu2Sb2 and GdAl2Ga2. These three compounds were found to order antiferromagnetically, with TN=6.5 K, 15.8 K, and 42.4 K respectively. The electric field gradient V22 derived from the quadrupole splitting of the Mössbauer spectra gives rise to a sign change at the end of the T3d series in GdT2Sb2, as was observed previously also for the corresponding compounds with Si and Ge. This behaviour was explained in terms of decreasing hybridization between the Gd valence electron states and the d electron states of the T atoms. 相似文献
993.
Stefano Borocci Carmen Cerchia Alessandro Grottesi Nico Sanna Ingrid Guarnetti Prandi Nabil Abid Andrea R. Beccari Giovanni Chillemi Carmine Talarico 《International journal of molecular sciences》2021,22(11)
The COVID-19 pandemic is caused by SARS-CoV-2. Currently, most of the research efforts towards the development of vaccines and antibodies against SARS-CoV-2 were mainly focused on the spike (S) protein, which mediates virus entry into the host cell by binding to ACE2. As the virus SARS-CoV-2 continues to spread globally, variants have emerged, characterized by multiple mutations of the S glycoprotein. Herein, we employed microsecond-long molecular dynamics simulations to study the impact of the mutations of the S glycoprotein in SARS-CoV-2 Variant of Concern 202012/01 (B.1.1.7), termed the “UK variant”, in comparison with the wild type, with the aim to decipher the structural basis of the reported increased infectivity and virulence. The simulations provided insights on the different dynamics of UK and wild-type S glycoprotein, regarding in particular the Receptor Binding Domain (RBD). In addition, we investigated the role of glycans in modulating the conformational transitions of the RBD. The overall results showed that the UK mutant experiences higher flexibility in the RBD with respect to wild type; this behavior might be correlated with the increased transmission reported for this variant. Our work also adds useful structural information on antigenic “hotspots” and epitopes targeted by neutralizing antibodies. 相似文献
994.
Francesca D'Amico Rishov Mukhopadhyay Prof. Dr. Huib Ovaa Dr. Monique P. C. Mulder 《Chembiochem : a European journal of chemical biology》2021,22(12):2011-2031
The ubiquitylation machinery regulates several fundamental biological processes from protein homeostasis to a wide variety of cellular signaling pathways. As a consequence, its dysregulation is linked to diseases including cancer, neurodegeneration, and autoimmunity. With this review, we aim to highlight the therapeutic potential of targeting E3 ligases, with a special focus on an emerging class of RING ligases, named tri-partite motif (TRIM) proteins, whose role as targets for drug development is currently gaining pharmaceutical attention. TRIM proteins exert their catalytic activity as scaffolds involved in many protein–protein interactions, whose multidomains and adapter-like nature make their druggability very challenging. Herein, we give an overview of the current understanding of this class of single polypeptide RING E3 ligases and discuss potential targeting options. 相似文献
995.
Michelle L. M. Mulder Xuehui He Juul M. P. A. van den Reek Paulo C. M. Urbano Charlotte Kaffa Xinhui Wang Bram van Cranenbroek Esther van Rijssen Frank H. J. van den Hoogen Irma Joosten Wynand Alkema Elke M. G. J. de Jong Ruben L. Smeets Mark H. Wenink Hans J. P. M. Koenen 《International journal of molecular sciences》2021,22(20)
Psoriasis (Pso) is a chronic inflammatory skin disease, and up to 30% of Pso patients develop psoriatic arthritis (PsA), which can lead to irreversible joint damage. Early detection of PsA in Pso patients is crucial for timely treatment but difficult for dermatologists to implement. We, therefore, aimed to find disease-specific immune profiles, discriminating Pso from PsA patients, possibly facilitating the correct identification of Pso patients in need of referral to a rheumatology clinic. The phenotypes of peripheral blood immune cells of consecutive Pso and PsA patients were analyzed, and disease-specific immune profiles were identified via a machine learning approach. This approach resulted in a random forest classification model capable of distinguishing PsA from Pso (mean AUC = 0.95). Key PsA-classifying cell subsets selected included increased proportions of differentiated CD4+CD196+CD183-CD194+ and CD4+CD196-CD183-CD194+ T-cells and reduced proportions of CD196+ and CD197+ monocytes, memory CD4+ and CD8+ T-cell subsets and CD4+ regulatory T-cells. Within PsA, joint scores showed an association with memory CD8+CD45RA-CD197- effector T-cells and CD197+ monocytes. To conclude, through the integration of in-depth flow cytometry and machine learning, we identified an immune cell profile discriminating PsA from Pso. This immune profile may aid in timely diagnosing PsA in Pso. 相似文献
996.
997.
Barbora Mikolaskova Matus Jurcik Ingrid Cipakova Tomas Selicky Jan Jurcik Silvia Bagelova Polakova Erika Stupenova Andrej Dudas Barbara Sivakova Jana Bellova Peter Barath Lucia Aronica Juraj Gregan Lubos Cipak 《International journal of molecular sciences》2021,22(13)
Pre-mRNA splicing is a key process in the regulation of gene expression. In the fission yeast Schizosaccharomyces pombe, Nrl1 regulates splicing and expression of several genes and non-coding RNAs, and also suppresses the accumulation of R-loops. Here, we report analysis of interactions between Nrl1 and selected RNA-processing proteins and regulation of Nrl1 function by phosphorylation. Bacterial two-hybrid system (BACTH) assays revealed that the N-terminal region of Nrl1 is important for the interaction with ATP-dependent RNA helicase Mtl1 while the C-terminal region of Nrl1 is important for interactions with spliceosome components Ctr1, Ntr2, and Syf3. Consistent with this result, tandem affinity purification showed that Mtl1, but not Ctr1, Ntr2, or Syf3, co-purifies with the N-terminal region of Nrl1. Interestingly, mass-spectrometry analysis revealed that in addition to previously identified phosphorylation sites, Nrl1 is also phosphorylated on serines 86 and 112, and that Nrl1-TAP co-purifies with Cka1, the catalytic subunit of casein kinase 2. In vitro assay showed that Cka1 can phosphorylate bacterially expressed Nrl1 fragments. An analysis of non-phosphorylatable nrl1 mutants revealed defects in gene expression and splicing consistent with the notion that phosphorylation is an important regulator of Nrl1 function. Taken together, our results provide insights into two mechanisms that are involved in the regulation of the spliceosome-associated factor Nrl1, namely domain-specific interactions between Nrl1 and RNA-processing proteins and post-translational modification of Nrl1 by phosphorylation. 相似文献
998.
999.
1000.
Bing Zhao Bogdan Karpiak Dmitrii Khokhriakov Annika Johansson Anamul Md. Hoque Xiaoguang Xu Yong Jiang Ingrid Mertig Saroj P. Dash 《Advanced materials (Deerfield Beach, Fla.)》2020,32(38):2000818
An outstanding feature of topological quantum materials is their novel spin topology in the electronic band structures with an expected large charge-to-spin conversion efficiency. Here, a charge-current-induced spin polarization in the type-II Weyl semimetal candidate WTe2 and efficient spin injection and detection in a graphene channel up to room temperature are reported. Contrary to the conventional spin Hall and Rashba–Edelstein effects, the measurements indicate an unconventional charge-to-spin conversion in WTe2, which is primarily forbidden by the crystal symmetry of the system. Such a large spin polarization can be possible in WTe2 due to a reduced crystal symmetry combined with its large spin Berry curvature, spin–orbit interaction with a novel spin-texture of the Fermi states. A robust and practical method is demonstrated for electrical creation and detection of such a spin polarization using both charge-to-spin conversion and its inverse phenomenon and utilized it for efficient spin injection and detection in the graphene channel up to room temperature. These findings open opportunities for utilizing topological Weyl materials as nonmagnetic spin sources in all-electrical van der Waals spintronic circuits and for low-power and high-performance nonvolatile spintronic technologies. 相似文献