bluuebunny/crossref_metadata_2025_split huggingface dataset:
FINDING DESCENDING SEQUENCES THROUGH ILL-FOUNDED LINEAR ORDERS
Authors: GOH JUN LE , PAULY ARNO , VALENTI MANLIO 
Published: February 2021

AbstractIn this work we investigate the Weihrauch degree of the problem Decreasing Sequence (
$\mathsf {DS}$
) of finding an infinite descending sequence through a given ill-founded linear order, which is shared by the problem Bad Sequence (
$\mathsf {BS}$
) of finding a bad sequence through a given non-well quasi-order. We show that
$\mathsf {DS}$
, despite being hard to solve (it has computable inputs with no hyperarithmetic solution), is rather weak in terms of uniform computational strength. To make the latter precise, we introduce the notion of the deterministic part of a Weihrauch degree. We then generalize
$\mathsf {DS}$
and
$\mathsf {BS}$
by considering
$\boldsymbol {\Gamma }$
-presented orders, where
$\boldsymbol {\Gamma }$
is a Borel pointclass or
$\boldsymbol {\Delta }^1_1$
,
$\boldsymbol {\Sigma }^1_1$
,
$\boldsymbol {\Pi }^1_1$
. We study the obtained
$\mathsf {DS}$
-hierarchy and
$\mathsf {BS}$
-hierarchy of problems in comparison with the (effective) Baire hierarchy and show that they do not collapse at any finite level.
Decoupling of morphological disparity and taxonomic diversity during the end-Permian mass extinction
Authors: Wan Junyu , Foster William J. , Tian Li , Stubbs Thomas L. , Benton Michael J. , Qiu Xincheng , Yuan Aihua 
Published: February 2021

AbstractAn increasing number of unexpectedly diverse benthic communities are being reported from microbially precipitated carbonate facies in shallow-marine platform settings after the end-Permian mass extinction. Ostracoda, which was one of the most diverse and abundant metazoan groups during this interval, recorded its greatest diversity and abundance associated with these facies. Previous studies, however, focused mainly on taxonomic diversity and, therefore, left room for discussion of paleoecological significance. Here, we apply a morphometric method (semilandmarks) to investigate morphological variance through time to better understand the ecological consequences of the end-Permian mass extinction and to examine the hypothesis that microbial mats played a key role in ostracod survival. Our results show that taxonomic diversity and morphological disparity were decoupled during the end-Permian extinction and that morphological disparity declined rapidly at the onset of the end-Permian extinction, even though the high diversity of ostracods initially survived in some places. The decoupled changes in taxonomic diversity and morphological disparity suggest that the latter is a more robust proxy for understanding the ecological impact of the extinction event, and the low morphological disparity of ostracod faunas is a consequence of sustained environmental stress or a delayed post-Permian radiation. Furthermore, the similar morphological disparity of ostracods between microbialite and non-microbialite facies indicates that microbial mats most likely represent a taphonomic window rather than a biological refuge during the end-Permian extinction interval.
Feasible Arm Configurations and its Application for Human-Like Motion Control of S-R-S-Redundant Manipulators with Multiple Constraints
Authors: Xia Jing , Jiang Zai-nan , Zhang Ting 
Published: February 2021

SUMMARYThis paper presents a general framework for human-like motion control of 7-DOF S-R-S-redundant manipulators. The new framework simultaneously accomplishes five objectives: Cartesian trajectory tracking, obstacle avoidance, joint limit avoidance, human-like movement, and a feasibility evaluation of the Cartesian trajectory.We exhaustively compute all feasible arm configurations. This allows for quick evaluations of the feasibility of the Cartesian trajectories. They are applied to inverse kinematics of the redundant manipulator to improve the capability to handle multiple constraints, and enable the manipulator to imitate human movements. The efficiency of the proposed framework is demonstrated by kinematic experiments with a humanoid robot.
Diversity of SARS-CoV-2 isolates driven by pressure and health index
Authors: Singh R. K. Sanayaima , Malik Md. Zubbair , Singh R. K. Brojen 
Published: February 2021

Abstract
One of the main concerns about the fast spreading coronavirus disease 2019 (Covid-19) pandemic is how to intervene. We analysed severe acute respiratory syndrome-coronavirus-2 (SARS-CoV-2) isolates data using the multifractal approach and found a rich in viral genome diversity, which could be one of the root causes of the fast Covid-19 pandemic and is strongly affected by pressure and health index of the hosts inhabited regions. The calculated mutation rate (mr) is observed to be maximum at a particular pressure, beyond which mr maintains diversity. Hurst exponent and fractal dimension are found to be optimal at a critical pressure (Pm), whereas, for P > Pm and P < Pm, we found rich genome diversity relating to complicated genome organisation and virulence of the virus. The values of these complexity measurement parameters are found to be increased linearly with health index values.
CHAIN COMPONENTS WITH THE STABLE SHADOWING PROPERTY FOR C1 VECTOR FIELDS
Authors: LEE MANSEOB , TIEN LE HUY 
Published: February 2021

AbstractLet M be a closed n-dimensional smooth Riemannian manifold, and let X be a $C^1$-vector field of $M.$ Let $\gamma $ be a hyperbolic closed orbit of $X.$ In this paper, we show that X has the $C^1$-stably shadowing property on the chain component $C_X(\gamma )$ if and only if $C_X(\gamma )$ is the hyperbolic homoclinic class.
Modeling Intra‐Caldera Resurgence Settings: Laboratory Experiments With Application to the Los Humeros Volcanic Complex (Mexico)
Authors: Bonini Marco , Maestrelli Daniele , Corti Giacomo , Del Ventisette Chiara , Moratti Giovanna , Carrasco‐Núñez Gerardo , Giordano Guido , Lucci Federico , Norini Gianluca , Piccardi Luigi , Urbani Stefano , Montanari Domenico 
Published: February 2021

AbstractScaled analogue models explored the role of different boundary conditions in intra‐caldera resurgence processes. Models investigated the role of magma intrusion depth (ID) (Series 1), asymmetric and symmetric caldera collapse (Series 2), as well as the presence of existing discontinuities in the pre‐volcanic substratum (Series 3) on the style of caldera resurgence. Experimental results indicate that different IDs resulted in different resurgence styles and structural patterns, which evolved from piston‐like resurgence, for deeper intrusions, to intra‐caldera resurgent domes for shallower intrusions. Asymmetric collapse was typically accompanied by a tilted roof block above the emptied analogue magma reservoir, while inherited faults influenced significantly the deformation pattern of piston‐like resurgence. Experiments simulate many of the principal characteristics of calderas. We compare our modeling results primarily to the Los Potreros caldera nested within the Los Humeros Volcanic Complex, where the largest Mexico's Quaternary eruption occurred and which hosts an important geothermal field (eastern Trans‐Mexican Volcanic Belt). A structural field survey was conducted to identify the kinematics of faults within the caldera and outside the volcanic edifice. The Los Potreros caldera shows a sub‐orthogonal fault pattern strikingly similar to that of models deformed with shallow ID. We interpret this correlation as an evidence of similarity in dynamic processes, whereby modeling results would indicate a scaled ID of ∼4.5 km. The Acoculco caldera complex, in Mexico, shows a fault pattern similar to the Los Potreros caldera, and geological information corroborates the attribution of renewed magmatic pressure to similar IDs.
Isotopic Constraint on the Sources and Biogeochemical Cycling of Nitrate in the Jiulong River Estuary
Authors: Wang Xin , Wu Xiaoyan , Chen Min , Cheng Hua , Chen Nengwang , Yang Weifeng , Cai Yihua 
Published: February 2021

AbstractNitrate concentrations and isotopic compositions (δ15N‐NO3− and δ18O‐NO3−) in the Jiulong River Estuary (JRE) were determined in 2014 to better understand the transformation and source contributions of nitrate. In contrast to nitrate concentrations, which generally followed a conservative binary mixing pattern, both δ15N‐NO3− and δ18O‐NO3− deviated significantly from the binary isotopic mixing lines during all sampling cruises, indicating a dynamic transformation of nitrate in the JRE. The deviation of nitrate isotopic signatures from conservative mixing lines as well as the slope of the regression between N and O isotopes (δ15N‐NO3− vs. δ18O‐NO3−) had significant seasonal variability, showing the seasonal shifting of the dominant nitrification and sedimentary denitrification in the JRE. Furthermore, the elevated nitrate concentrations and isotopic compositions in the lower JRE during the dry season, along with an isotope regression slope of 1.16, indicated a significant local input of nitrate. Nitrate source apportionment is carried out through the Stable Isotope Analyses in R model with the incorporation of nitrate isotopic fractionation factors for nitrification and denitrification in the JRE. The model results revealed that fertilizer is the largest nitrate source to the JRE, contributing 33%–55% of the nitrate throughout the sampling period. Manure is another major source and contributed 32%–39% of the nitrate to the JRE. Sewage nitrate contributions to the JRE were 7% during April and June but dramatically increased to 18% during the wet season, probably as a result of the rapid flushing of suburban and rural untreated domestic sewage into the river.
EOMES and IL-10 regulate antitumor activity of T regulatory type 1 CD4+ T cells in chronic lymphocytic leukemia
Authors: Roessner Philipp M. , Llaó Cid Laura , Lupar Ekaterina , Roider Tobias , Bordas Marie , Schifflers Christoph , Arseni Lavinia , Gaupel Ann-Christin , Kilpert Fabian , Krötschel Marit , Arnold Sebastian J. , Sellner Leopold , Colomer Dolors , Stilgenbauer Stephan , Dietrich Sascha , Lichter Peter , Izcue Ana , Seiffert Martina 
Published: February 2021

AbstractThe transcription factor eomesodermin (EOMES) promotes interleukin (IL)-10 expression in CD4+ T cells, which has been linked to immunosuppressive and cytotoxic activities. We detected cytotoxic, programmed cell death protein-1 (PD-1) and EOMES co-expressing CD4+ T cells in lymph nodes (LNs) of patients with chronic lymphocytic leukemia (CLL) or diffuse large B-cell lymphoma. Transcriptome and flow cytometry analyses revealed that EOMES does not only drive IL-10 expression, but rather controls a unique transcriptional signature in CD4+ T cells, that is enriched in genes typical for T regulatory type 1 (TR1) cells. The TR1 cell identity of these CD4+ T cells was supported by their expression of interferon gamma and IL-10, as well as inhibitory receptors including PD-1. TR1 cells with cytotoxic capacity accumulate also in Eµ-TCL1 mice that develop CLL-like disease. Whereas wild-type CD4+ T cells control TCL1 leukemia development after adoptive transfer in leukopenic Rag2−/− mice, EOMES-deficient CD4+ T cells failed to do so. We further show that TR1 cell-mediated control of TCL1 leukemia requires IL-10 receptor (IL-10R) signaling, as Il10rb-deficient CD4+ T cells showed impaired antileukemia activity. Altogether, our data demonstrate that EOMES is indispensable for the development of IL-10-expressing, cytotoxic TR1 cells, which accumulate in LNs of CLL patients and control TCL1 leukemia in mice in an IL-10R-dependent manner.
The positive effects of running exercise on hippocampal astrocytes in a rat model of depression
Authors: Li Yue , Luo Yanmin , Tang Jing , Liang Xin , Wang Jin , Xiao Qian , Zhu Peilin , Xiao Kai , Jiang Lin , Dou Xiaoyun , Huang Chunxia , Xie Yuhan , Tang Yong 
Published: February 2021

AbstractRunning exercise has been shown to alleviate depressive symptoms, but the mechanism of its antidepressant effect is still unclear. Astrocytes are the predominant cell type in the brain and perform key functions vital to central nervous system (CNS) physiology. Mounting evidence suggests that changes in astrocyte number in the hippocampus are closely associated with depression. However, the effects of running exercise on astrocytes in the hippocampus of depression have not been investigated. Here, adult male rats were subjected to chronic unpredictable stress (CUS) for 5 weeks followed by treadmill running for 6 weeks. The sucrose preference test (SPT) was used to assess anhedonia of rats. Then, immunohistochemistry and modern stereological methods were used to precisely quantify the total number of glial fibrillary acidic protein (GFAP)+ astrocytes in each hippocampal subregion, and immunofluorescence was used to quantify the density of bromodeoxyuridine (BrdU)+ and GFAP+ cells in each hippocampal subregion. We found that running exercise alleviated CUS-induced deficit in sucrose preference and hippocampal volume decline, and that CUS intervention significantly reduced the number of GFAP+ cells and the density of BrdU+/GFAP+ cells in the hippocampal CA1 region and dentate gyrus (DG), while 6 weeks of running exercise reversed these decreases. These results further confirmed that running exercise alleviates depressive symptoms and protects hippocampal astrocytes in depressed rats. These findings suggested that the positive effects of running exercise on astrocytes and the generation of new astrocytes in the hippocampus might be important structural bases for the antidepressant effects of running exercise.
Trazodone effects on developing brain
Authors: Korade Zeljka , Allen Luke B. , Anderson Allison , Tallman Keri A. , Genaro-Mattos Thiago C. , Porter Ned A. , Mirnics Karoly 
Published: February 2021

AbstractTrazodone (TRZ) is a commonly prescribed antidepressant with significant off-label use for insomnia. A recent drug screening revealed that TRZ interferes with sterol biosynthesis, causing elevated levels of sterol precursor 7-dehydrocholesterol (7-DHC). Recognizing the well-documented, disruptive effect of 7-DHC on brain development, we designed a study to analyze TRZ effects during pregnancy. Utilizing an in vivo model and human biomaterial, our studies were designed to also account for drug interactions with maternal or offspring Dhcr7 genotype. In a maternal exposure model, we found that TRZ treatment increased 7-DHC and decreased desmosterol levels in brain tissue in newborn pups. We also observed interactions between Dhcr7 mutations and maternal TRZ exposure, giving rise to the most elevated toxic oxysterols in brains of Dhcr7+/− pups with maternal TRZ exposure, independently of the maternal Dhcr7 genotype. Therefore, TRZ use during pregnancy might be a risk factor for in utero development of a neurodevelopmental disorder, especially when the unborn child is of DHCR7+/− genotype. The effects of TRZ on 7-DHC was corroborated in human serum samples. We analyzed sterols and TRZ levels in individuals with TRZ prescriptions and found that circulating TRZ levels correlated highly with 7-DHC. The abundance of off-label use and high prescription rates of TRZ might represent a risk for the development of DHCR7 heterozygous fetuses. Thus, TRZ use during pregnancy is potentially a serious public health concern.
Novel variants in the stem cell niche factor WNT2B define the disease phenotype as a congenital enteropathy with ocular dysgenesis
Authors: Zhang Yanjia Jason , Jimenez Lissette , Azova Svetlana , Kremen Jessica , Chan Yee-Ming , Elhusseiny Abdelrahman M. , Saeed Hajirah , Goldsmith Jeffrey , Al-Ibraheemi Alyaa , O’Connell Amy E. , Kovbasnjuk Olga , Rodan Lance , Agrawal Pankaj B. , Thiagarajah Jay R. 
Published: February 2021

AbstractWNT2B is a member of the Wnt family, a group of signal transduction proteins involved in embryologic development and stem cell renewal and maintenance. We recently reported homozygous nonsense variants in WNT2B in three individuals with severe, neonatal-onset diarrhea, and intestinal failure. Here we present a fourth case, from a separate family, with neonatal diarrhea associated with novel compound heterozygous WNT2B variants. One of the two variants was a frameshift variant (c.423del [p.Phe141fs]), while the other was a missense change (c.722 G > A [p.G241D]) that we predict through homology modeling to be deleterious, disrupting post-translational acylation. This patient presented as a neonate with severe diet-induced (osmotic) diarrhea and growth failure resulting in dependence on parenteral nutrition. Her gastrointestinal histology revealed abnormal cellular architecture particularly in the stomach and colon, including oxyntic atrophy, abnormal distribution of enteroendocrine cells, and a paucity of colonic crypt glands. In addition to her gastrointestinal findings, she had bilateral corneal clouding and atypical genital development later identified as a testicular 46,XX difference/disorder of sexual development. Upon review of the previously reported cases, two others also had anterior segment ocular anomalies though none had atypical genital development. This growing case series suggests that variants in WNT2B are associated with an oculo-intestinal (and possibly gonadal) syndrome, due to the protein’s putative involvement in multiple developmental and stem cell maintenance pathways.
Single-cell mapping of focused ultrasound-transfected brain
Authors: Mathew A. S. , Gorick C. M. , Price R. J. 
Published: February 2021

AbstractGene delivery via focused ultrasound (FUS) mediated blood-brain barrier (BBB) opening is a disruptive therapeutic modality. Unlocking its full potential will require an understanding of how FUS parameters (e.g., peak-negative pressure (PNP)) affect transfected cell populations. Following plasmid (mRuby) delivery across the BBB with 1 MHz FUS, we used single-cell RNA-sequencing to ascertain that distributions of transfected cell types were highly dependent on PNP. Cells of the BBB (i.e., endothelial cells, pericytes, and astrocytes) were enriched at 0.2 MPa PNP, while transfection of cells distal to the BBB (i.e., neurons, oligodendrocytes, and microglia) was augmented at 0.4 MPa PNP. PNP-dependent differential gene expression was observed for multiple cell types. Cell stress genes were upregulated proportional to PNP, independent of cell type. Our results underscore how FUS may be tuned to bias transfection toward specific brain cell types in vivo and predict how those cells will respond to transfection.
Hydrogen sulfide promotes flowering in heading Chinese cabbage by S-sulfhydration of BraFLCs
Authors: Ma Xiaoli , Zhang Liping , Pei Zhuoya , Zhang Linlin , Liu Zhiqiang , Liu Danmei , Hao Xuefeng , Jin Zhuping , Pei Yanxi 
Published: February 2021

AbstractHeading Chinese cabbage (Brassica rapaL. syn.B.campestrisL. ssp.chinensisMakino var.pekinensis(Rupr.) J. Cao et Sh. Cao) is a cruciferousBrassicavegetable that has a triplicate genome, owing to an ancient genome duplication event. It is unclear whether the duplicated homologs have conserved or diversified functions. Hydrogen sulfide (H2S) is a plant gasotransmitter that plays important physiological roles in growth, development, and responses to environmental stresses. The modification of cysteines through S-sulfhydration is an important mechanism of H2S, which regulates protein functions. H2S promotes flowering inArabidopsisand heading Chinese cabbage. Here we investigated the molecular mechanisms of H2S used to promote flowering in the latter. Four, five, and fourBraFLC,BraSOC I, andBraFThomologs were identified in heading Chinese cabbage. Different BraFLC proteins were bound to different CArG boxes in the promoter regions of theBraSOC IandBraFThomologs, producing different binding patterns. Thus, there may be functionally diverseBraFLChomologs in heading Chinese cabbage. Exogenous H2S at 100 μmol L−1significantly promoted flowering by compensating for insufficient vernalization. BraFLC 1 and BraFLC 3 underwent S-sulfhydration by H2S, after which their abilities to bind mostBraSOC IorBraFTpromoter probes weakened or even disappeared. These changes in binding ability were consistent with the expression pattern of theBraFTandBraSOC Ihomologs in seedlings treated with H2S. These results indicated that H2S signaling regulates flowering time. In summary, H2S signaling promoted plant flowering by weakening or eliminating the binding abilities of BraFLCs to downstream promoters through S-sulfhydration.
Site-directed mutagenesis identified the key active site residues of alcohol acyltransferase PpAAT1 responsible for aroma biosynthesis in peach fruits
Authors: Song Zhi-Zhong , Peng Bin , Gu Zi-Xia , Tang Mei-Ling , Li Bei , Liang Mei-Xia , Wang Li-Min , Guo Xiao-Tong , Wang Jian-Ping , Sha Yu-Fen , Zhang Hong-Xia 
Published: February 2021

AbstractThe aroma of peach fruit is predominantly determined by the accumulation of γ-decalactone and ester compounds. A previous study showed that the biosynthesis of these aroma compounds in peach fruit is catalyzed by PpAAT1, an alcohol acyltransferase. In this work, we investigated the key active site residues responsible for γ-decalactone and ester biosynthesis. A total of 14 candidate amino acid residues possibly involved in internal esterification and 9 candidate amino acid residues possibly involved in esterification of PpAAT1 were assessed via site-directed mutagenesis. Analyses of the in vitro enzyme activities of PpAAT1 and its site-directed mutant proteins (PpAAT1-SMs) with different amino acid residue mutations as well as the contents of γ-decalactone in transgenic tobacco leaves and peach fruits transiently expressing PpAAT1 and PpAAT1-SMs revealed that site-directed mutation of H165 in the conserved HxxxD motif led to lost enzymatic activity of PpAAT1 in both internal esterification and its reactions, whereas mutation of the key amino acid residue D376 led to the total loss of γ-decalactone biosynthesis activity of PpAAT1. Mutations of 9 and 7 other amino acid residues also dramatically affected the enzymatic activity of PpAAT1 in the internal esterification and esterification reactions, respectively. Our findings provide a biochemical foundation for the mechanical biosynthesis of γ-decalactone and ester compounds catalyzed by PpAAT1 in peach fruits, which could be used to guide the molecular breeding of new peach species with more favorable aromas for consumers.