bluuebunny/crossref_metadata_2025 huggingface dataset:
Natural variation inGmRAVconfers ecological adaptation through photoperiod control of flowering time and maturity in soybean
Authors: Wang Yuhe , Xu Chongjing , Sun Jiafan , Dong Lidong , Li Minmin , Liu Ying , Wang Jianhui , Zhang Xiaoming , Li Dongmei , Sun Jingzhe , Zhang Yuntong , Shan Jinming , Li Wenbin , Zhao Lin
Published: January 2021

Photoperiod strictly controlled vegetative and reproductive growth stages in soybean. A soybeanGmRAVtranscription factor containing both AP2 and B3 domains was shown to be a key component of this process. We identified six polymorphisms inGmRAVpromoter that showed significant association with flowering time and maturity of soybean in one or multiple environments. Soybean varieties with minor polymorphism exhibited longer growth period contributing to soybean adaptation to lower latitudes. The cis-acting element GT1CONSENSUS motif ofGmRAVpromoter controlled the growth period and shortened R5-R7 by reducing the expression level ofGmRAVin soybean. ThreeGmRAV-overexpressing (GmRAV-ox)transgenic lines displayed later flowering time and maturity, shorter height and fewer numbers of leaves compared with control plants, and transgenic inhibition ofGmRAV (GmRAV-i)soybean displayed earlier flowering time and maturity, and increased plant heights. 163 GmRAV-target genes were determined to be putatively directly bound and transcriptionally regulated by GmRAV by combining the results from the DAP-seq and RNA-seq analyses. Two GmRAV binding motifs [C(A/G/T)A(C)ACAA(G/T)A(C/T)A(G/T)] and [C(T/A)A(C/T) C(T/G)CTG] were identified.GmRAVacting downstream ofE3E4delayed soybean growth period by repressingGmFT5atranscriptional activity to guaranteed both vegetative and reproductive phase long enough to allow necessary energy reserved to be accumulated.
Antifungal activities of artesunate, chloramphenicol, and cotrimoxazole againstBasidiobolusspecies, the causal agents of gastrointestinal basidiobolomycosis
Authors: Al-Qahtani Saleh , Joseph Martin R.P. , Al Hakami Ahmed M. , Asseri Ali A. , Mathew Anjali , Al Bshabshe Ali , Alhumayed Suliman , Hamid Mohamed E.
Published: January 2021

Basidiobolusspecies (n =13) isolated from human gastrointestinal basidiobolomycosis and lizards were tested against artesunate, chloramphenicol, and cotrimoxazole. The three agents exhibited inhibitory actions againstBasidiobolusspecies comparable to the known antifungals. The combined effects of artesunate + voriconazole and cotrimoxazole + voriconazole have significant synergic effects, p = 0.003 and p = 0.021, respectively. These are promising results that enhance accelerated combined treatment of GIB in humans particularly the combination of artesunate and voriconazole.
Mapping of m6A and Its Regulatory Targets in Prostate Cancer Reveals a METTL3-low Induction of Therapy Resistance
Authors: Cotter Kellie A. , Gallon John , Uebersax Nadine , Rubin Philip , Meyer Kate D. , Piscuoglio Salvatore , Jaffrey Samie R. , Rubin Mark A.
Published: January 2021

Recent evidence has highlighted the role ofN6-methyladenosine (m6A) in the regulation of mRNA expression, stability and translation, supporting a potential role for post-transcriptional regulation mediated by m6A in cancer. Here we explore prostate cancer as an exemplar and demonstrate that low levels ofN6-adenosine-methyltransferase (METTL3) is associated with advanced metastatic disease. To explore this relationship, we generated the first prostate m6A maps, and further examined howMETTL3regulates expression at the level of transcription, translation, and protein. Significantly, transcripts encoding extracellular matrix proteins are consistently upregulated withMETTL3knockdown. We also examined the relationship betweenMETTL3and androgen signaling and discovered the upregulation of a hepatocyte nuclear factor-driven gene signature that is associated with therapy resistance in prostate cancer. Significantly,METTL3knockdown rendered the cells resistant to androgen receptor antagonists, implicating changes in m6A as a mechanism for therapy resistance in metastatic prostate cancer.
Inhibitor Binding Modulates Protonation States in the Active Site of SARS-CoV-2 Main Protease
Authors: Kneller Daniel W. , Phillips Gwyndalyn , Weiss Kevin L. , Zhang Qiu , Coates Leighton , Kovalevsky Andrey
Published: January 2021

The main protease (3CL Mpro) from SARS-CoV-2, the virus that causes COVID-19, is an essential enzyme for viral replication with no human counterpart, making it an attractive drug target. Although drugs have been developed to inhibit the proteases from HIV, hepatitis C and other viruses, no such therapeutic is available to inhibit the main protease of SARS-CoV-2. To directly observe the protonation states in SARS-CoV-2 Mproand to elucidate their importance in inhibitor binding, we determined the structure of the enzyme in complex with the α-ketoamide inhibitor telaprevir using neutron protein crystallography at near-physiological temperature. We compared protonation states in the inhibitor complex with those determined for a ligand-free neutron structure of Mpro. This comparison revealed that three active-site histidine residues (His41, His163 and His164) adapt to ligand binding, altering their protonation states to accommodate binding of telaprevir. We suggest that binding of other α-ketoamide inhibitors can lead to the same protonation state changes of the active site histidine residues. Thus, by studying the role of active site protonation changes induced by inhibitors we provide crucial insights to help guide rational drug design, allowing precise tailoring of inhibitors to manipulate the electrostatic environment of SARS-CoV-2 Mpro.
Acute inflammation, mediated by lung neutrophils, confers enhanced protection againstMycobacterium tuberculosisinfection in mice
Authors: Piergallini Tucker J. , Scordo Julia M. , Pino Paula A. , Torrelles Jordi B. , Turner Joanne
Published: January 2021

Inflammation plays a crucial role in the control ofMycobacterium tuberculosis(M.tb) infection. In this study, we demonstrate that an inflammatory pulmonary environment at the time of infection mediated by liposaccharide (LPS) treatment in mice confers enhanced protection againstM.tbfor up to 6 months post infection. This transient protective inflammatory environment was associated with a neutrophil and monocyte/macrophage influx as well as increased inflammatory cytokines.In vitroinfection of neutrophils from LPS treated mice demonstrated that LPS neutrophils exhibited increased recognition ofM.tb, and had a greater innate capacity for killingM.tb. Finally, partial depletion of neutrophils in LPS treated mice showed an increase inM.tbburden, suggesting neutrophils conferred the enhanced protection observed in LPS treated mice. These results indicate a positive role of an inflammatory environment during initialM.tbinfection, and suggests that acute inflammation at the time ofM.tbinfection can positively alter disease outcome.
A wave optics model for the effect of partial coherence on coherent diffractive imaging
Authors: Zhu Zhongzhu , Xu Han , Hu Lingfei , Li Ming , Liu Peng , Dong Yuhui , Zhou Liang
Published: January 2021

With the development of fourth-generation synchrotron sources, coherent diffractive imaging (CDI) will be a mainstream method for 3D structure determination at nanometre resolution. The partial coherence of incident X-rays plays a critical role in the reconstructed image quality. Here a wave optics model is proposed to analyze the effect of partial coherence on CDI for an actual beamline layout, based on the finite size of the source and the influence of the optics on the wavefront. Based on this model, the light field distribution at any plane, the coherence between any two points on this plane and CDI experiments can be simulated. The plane-wave CDI simulation result also shows that in order to reconstruct good image quality of complex samples the visibility of the interference fringes of any two points in the horizontal and vertical directions of the incident light field at the sample needs to be higher than 0.95.
Δ9-Tetrahydrocannabinolic acid A, the precursor to Δ9-tetrahydrocannabinol (THC)
Authors: Skell Jeffrey M. , Kahn Michael , Foxman Bruce M.
Published: January 2021

While Δ9-tetrahydrocannabinolic acid A (THCA-A) has been reported to be difficult to crystallize and/or amorphous, we have obtained THCA-A in a pure crystalline form by extraction of marijuana and selective fractionation with liquid CO2. THCA-A (systematic name: 1-hydroxy-6,6,9-trimethyl-3-pentyl-6a,7,8,10a-tetrahydro-6H-benzo[c]isochromene-2-carboxylic acid, C22H30O4) crystallizes in the orthorhombic space group P212121, with Z = 8 and Z′ = 2. The two independent molecules are related by a pseudo-twofold axis centered between the two –CO2H groups, but the conformations of the two –C5H11 chains are quite different (tgt and ttg; t is trans and g is gauche). The carboxylate groups form an intermolecular R
2
2(8) hydrogen-bonded ring; the two C2O2 carboxylate planes are twisted out of the planes of the attached arene rings in opposite directions by 13.59 (8) and 18.92 (8)°, respectively, with a resultant interplanar angle of 28.89 (8)°. Each molecule also has an intramolecular S(6) hydrogen-bond motif between the ortho –OH group and the dihydropyran-ring O atom. Other conformational aspects of the two independent molecules are quite similar to those found in the previously determined structure of THCA-B. THCA-A has shown promise in a number of medical applications. Demonstration of the crystallinity and details of the crystal structure are expected to provide a standard point of departure for chemical and medical experiments.
Money Moves the Mare: The Response of Community‐Based Organizations to Health Care's Embrace of Social Determinants
Authors: TAYLOR LAUREN A. , BYHOFF ELENA
Published: January 2021

Policy Points

Health policies that encourage health and social integration can induce community‐based organizations (CBOs) to adopt new ways of working from health care organizations, including their language, staffing patterns, and metrics. These changes can be explained by CBOs’ perceptions that health care organizations may provide new sources of revenue.

While the welfare implications of these changes are not yet known, policymakers should consider balancing the benefits of professionalizing CBOs against the risks of medicalizing them.

Context

Recent health policies incentivize health care providers to collaborate with community‐based organizations (CBOs), such as food pantries and homeless shelters, to address patients’ social determinants of health (SDOH). The perspectives of health care leaders on these policy changes have been studied, but the perspectives of CBO managers have not.

Methods

Our research question was: How are CBOs in Massachusetts perceiving and responding to new Medicaid policies that encourage collaboration between health care organizations and CBOs? We interviewed 46 people in leadership positions at CBOs in Massachusetts for approximately an hour each. We analyzed these data abductively, meaning that we iterated between inductively coding transcripts and consulting existing theories and frameworks.

Findings

We found evidence of a knowing‐doing gap among CBOs. Even though CBOs value their distinctiveness and autonomy from health care, they have undertaken a series of organizational changes in response to the new Medicaid policy that make their organizations appear more like health care organizations. These changes include adopting new performance metrics, hiring clinical staff to the board and senior management positions, and using medical language to describe nonmedical work. Drawing on institutional theory, we suggest that the nonprofits undertake such changes in an effort to demonstrate legitimacy to health care organizations, who may be able to provide new sources of critically needed revenue.

Conclusions

Massachusetts CBOs perceive health systems as potential sources of revenue, due in part to an ongoing Medicaid redesign that encourages the integration of health and social services. This perception is driving CBOs to appear more like health care organizations, but the impacts of these changes on welfare remain unknown.
Sociodemographic and health‐related determinants of seasonal influenza vaccination in pregnancy: A systematic review and meta‐analysis of the evidence since 2000
Authors: Okoli George N. , Reddy Viraj K. , Al‐Yousif Yahya , Neilson Christine J. , Mahmud Salaheddin M. , Abou‐Setta Ahmed M.
Published: January 2021

Introduction

Vaccination is considered to be the most practical and effective preventative measure against influenza. It is highly recommended for population subgroups most at risk of developing complications, including pregnant women. However, seasonal influenza vaccine uptake remains suboptimal among pregnant women, even in jurisdictions with universal vaccination. We summarized the evidence on the determinants of seasonal influenza vaccine uptake during pregnancy to better understand factors that influence vaccine uptake among pregnant women.

Material and methods

We systematically searched MEDLINE, Embase and CINAHL from January 2000 to February 2020 for publications in English reporting on sociodemographic and/or health‐related determinants of seasonal influenza vaccine uptake during pregnancy. Two reviewers independently included studies. One reviewer extracted data and assessed study quality, and another reviewer checked extracted data and study quality assessments for errors. Disagreements were resolved through consensus, or a third reviewer. We meta‐analyzed using the inverse variance, random‐effects method, and reported the odds ratios (OR) and 95% confidence intervals (CI).

Results

From 1663 retrieved citations, we included 36 studies. The following factors were associated with increased seasonal influenza vaccine uptake: Older age (20 studies: OR 1.13, 95% CI 1.07‐1.20), being nulliparous (13 studies: OR 1.26, 95% CI 1.15‐1.38), married (8 studies: OR 1.11, 95% CI 1.07‐1.15), employed (4 studies: OR 1.13, 95% CI 1.02‐1.24), a non‐smoker (8 studies: OR 1.25, 95% CI 1.04‐1.51) and having prenatal care (3 studies: OR 3.36, 95% CI 2.25‐5.02), a chronic condition (6 studies: OR 1.30, 95% CI 1.17‐1.44), been previously vaccinated (9 studies: OR 4.88, 95% CI 3.14‐7.57) and living in a rural area (9 studies: OR 1.09, 95% CI 1.05‐1.14). Compared with being black, being white was also associated with increased seasonal influenza vaccine uptake (11 studies: OR 1.30, 95% CI 1.20‐1.41).

Conclusions

The evidence suggests that several sociodemographic and health‐related factors may determine seasonal influenza vaccination in pregnancy, and that parity, history of influenza vaccination, prenatal care and comorbidity status may be influential.
Family socio‐economic status and children’s executive function: The moderating effects of parental subjective socio‐economic status and children’s subjective social mobility
Authors: Ming Hua , Zhang Feng , Jiang Ying , Ren Yi , Huang Silin
Published: January 2021

Family socio‐economic status (SES) is significantly related to disparities in children’s executive function. Children from economically disadvantaged backgrounds perform worse on executive function tasks than their peers from high‐SES families. The protective factors in the relationship between SES and executive function have not been sufficiently investigated, especially from the perspective of parents’ and children’s perceptions and expectations regarding SES. Therefore, this study aimed to examine whether parental subjective SES and children’s subjective social mobility separately moderated the relationship between family SES and children’s executive function among 885 participants aged 9–13 years. The results showed that family SES was positively related to the three components of executive function (cognitive flexibility, inhibitory control, and working memory). Moreover, the relationship between SES and cognitive flexibility was weak among the children with a high level of subjective social mobility or those whose parents had high levels of subjective SES. Among children from families with economic hardship, subjective social mobility is a potential protective factor mitigating the negative effects of low family SES on their cognitive flexibility.
Non‐vitamin K antagonist oral anticoagulants versus warfarin in AF patients ≥ 85 years
Authors: Tsai Chuan‐Tsai , Liao Jo‐Nan , Chen Su‐Jung , Jiang Yu‐Ru , Chen Tzeng‐Ji , Chao Tze‐Fan
Published: January 2021

Background

Atrial fibrillation (AF) prevalence and its risk of stroke rise with ageing. We aimed to investigate the outcomes of NOAC and warfarin in AF patients aged ≥ 85 years.

Methods

This is a retrospective study using Taiwan National Health Insurance Research Database. A total of 15,361 patients aged ≥ 85 years with AF on oral anticoagulants were identified. The end points included ischaemic stroke, intracranial haemorrhage (ICH), major bleeding, all‐cause mortality and composite adverse events (ICH or major bleeding or all‐cause mortality). Clinical outcomes were compared between each NOAC and warfarin after propensity matching.

Results

Before propensity matching, patients taking warfarin were older, more female with more comorbidities than NOACs users. After propensity matching, baseline characteristics did not differ significantly between matched subjects receiving warfarin and each NOAC. Compared to warfarin, dabigatran was associated with a lower risk of ICH (hazard ratio [HR] 0.496), mortality (HR 0.558) and adverse events (HR 0.628), while rivaroxaban was associated with a lower risk of ischaemic stroke (HR 0.781), ICH (HR 0.453), mortality (HR 0.558) and adverse events (HR 0.636). Apixaban was associated with a lower risk of mortality (HR 0.488) and adverse events (HR 0.557) compared to warfarin. (all P < .05).

Conclusion

For the efficacy, NOACs were associated with a comparable or lower risk of ischaemic stroke compared to warfarin. For adverse events, NOACs were associated with a lower risk of all‐cause mortality and composite adverse events. In the elderly AF population, NOACs could be a more favourable choice for stroke prevention.
Structure, content, unsafe abbreviations, and completeness of discharge summaries: A retrospective analysis in a University Hospital in Austria
Authors: Schwarz Christine Maria , Hoffmann Magdalena , Smolle Christian , Eiber Michael , Stoiser Bianca , Pregartner Gudrun , Kamolz Lars‐Peter , Sendlhofer Gerald
Published: January 2021

Rationale and objective

The discharge summary (DS) is one of the most important instruments to transmit information to the treating general physician (GP). The objective of this study was to analyse important components of DS, structural characteristics as well as medical and general abbreviations.

Method

One hundred randomly selected DS from five different clinics were evaluated by five independent reviewers regarding content, structure, abbreviations and conformity to the Austrian Electronic Health Records (ELGA) using a structured case report form. Abbreviations of all 100 DS were extracted. All items were scored on a 4‐point Likert‐type scale ranging from “strongly agree” to “strongly disagree” (or “not relevant”). Subsequently, the results were discussed among reviewers to achieve a consensus decision.

Results

The mandatory fields, reason for admission and diagnosis at discharge were present in 80% and 98% of DS. The last medication was fully scored in 48% and the recommended medication in 94% of 100 DS. There were significant overall differences among clinics for nine mandatory items. In total, 750 unexplained abbreviations were found in 100 DS.

Conclusions

In conclusion, DS are often lacking important items. Particularly important are a detailed medication history and recommendations for further medication that should always be listed in each DS. It is thus necessary to design and implement changes that improve the completeness of DS. An important quality improvement can be achieved by avoiding the use of ambiguous abbreviations.
Neutropenia in dogs receiving vincristine for treatment of presumptive immune‐mediated thrombocytopenia
Authors: LaQuaglia Kathryn A. , Robertson James B. , Lunn Katharine F.
Published: January 2021

Background

Neutropenia is an adverse effect of vincristine when used in multidrug chemotherapy protocols.

Objective

To determine the incidence of neutropenia, identify potential risk factors for neutropenia, and determine the effect of neutropenia on outcome, in dogs receiving vincristine for treatment of immune‐mediated thrombocytopenia (ITP).

Animals

One hundred twenty‐seven client‐owned dogs presumptively diagnosed with ITP.

Methods

In this retrospective cohort study, medical records were reviewed to identify dogs presumptively diagnosed with ITP, and treated with vincristine, over a 15‐year period. Logistic regression was used to identify risk factors for the development of neutropenia in dogs receiving vincristine. Time to platelet count ≥40 000 platelets/μL, survival, and duration of hospitalization were compared between neutropenic and non‐neutropenic dogs.

Results

Vincristine was administered to 127 dogs with presumptive ITP; 19 became neutropenic. Administration of cyclosporine was significantly (P < .001) associated with the development of neutropenia (odds ratio: 12.97, 95% confidence interval: 4.17, 40.35). There was no difference in median time to ≥40 000 platelets/μL between neutropenic dogs (4 days; range, 1‐14 days) and non‐neutropenic dogs (3 days; range, 0‐48 days). Percentage survival to discharge was 95% in both groups, but median duration of hospitalization was significantly longer in neutropenic dogs (6 days; range, 3‐22 days) compared to non‐neutropenic dogs (4 days; range, 2‐15 days).

Conclusions and Clinical Importance

Cyclosporine administration was associated with the development of neutropenia in dogs receiving vincristine, which might be related to effects on metabolism of vincristine. Neutrophil counts should be monitored in dogs receiving vincristine treatment for ITP, particularly if administered in conjunction with cyclosporine.
A manipulative interplay between positive and negative regulators of phytohormones: A way forward for improving drought tolerance in plants
Authors: Mubarik Muhammad Salman , Khan Sultan Habibullah , Sajjad Muhammad , Raza Ali , Hafeez Muhammad Bilal , Yasmeen Tahira , Rizwan Muhammad , Ali Shafaqat , Arif Muhammad Saleem
Published: January 2021

Among different abiotic stresses, drought stress is the leading cause of impaired plant growth and low productivity worldwide. It is therefore essential to understand the process of drought tolerance in plants and thus to enhance drought resistance. Accumulating evidence indicates that phytohormones are essential signaling molecules that regulate diverse processes of plant growth and development under drought stress. Plants can often respond to drought stress through a cascade of phytohormones signaling as a means of plant growth regulation. Understanding biosynthesis pathways and regulatory crosstalk involved in these vital compounds could pave the way for improving plant drought tolerance while maintaining overall plant health. In recent years, the identification of phytohormones related key regulatory genes and their manipulation through state‐of‐the‐art genome engineering tools have helped to improve drought tolerance plants. To date, several genes linked to phytohormones signaling networks, biosynthesis, and metabolism have been described as a promising contender for engineering drought tolerance. Recent advances in functional genomics have shown that enhanced expression of positive regulators involved in hormone biosynthesis could better equip plants against drought stress. Similarly, knocking down negative regulators of phytohormone biosynthesis can also be very effective to negate the negative effects of drought on plants. This review explained how manipulating positive and negative regulators of phytohormone signaling could be improvised to develop future crop varieties exhibiting higher drought tolerance. In addition, we also discuss the role of a promising genome editing tool, CRISPR/Cas9, on phytohormone mediated plant growth regulation for tackling drought stress.
Exogenous salicylic acid alleviates the negative impacts on production components, biomass and gas exchange in tomato plants under water deficit improving redox status and anatomical responses
Authors: Lobato Allan Klynger da Silva , Barbosa Maria Antonia Machado , Alsahli Abdulaziz Abdullah , Lima Emily Juliane Alvino , Silva Breno Ricardo Serrão da
Published: January 2021

Salicylic acid (SA) is an interesting messenger in plant metabolism that modulates multiple pathways, including the antioxidant defence pathway, and stimulates anatomical structures essential to carbon dioxide fixation during the photosynthetic process. The aim of this research was to determine whether pre‐treatment with exogenous SA can alleviate the deleterious effects induced by water deficit on production components, biomass and gas exchange, measuring reactive oxygen species, antioxidant enzymes, variables connected to photosynthetic machinery, anatomical responses, and agro‐morphological traits in tomato plants under water deficit. The experiment used a factorial design with four treatments, including two water conditions (control and water deficit) and two salicylic acid concentrations (0 and 0.1 mM salicylic acid). Water deficit negatively impacted the biomass and fruit number of tomato plants. Pre‐treatment using 0.1 mM SA in plants submitted to water restriction induced increments in fruit number, weight, and biomass. These results were related to the protective role triggered by this substance, stimulating superoxide dismutase (27.07%), catalase (17.81%), ascorbate peroxidase (50.52%), and peroxidase (10.81%) as well as reducing the cell damage (malondialdehyde and electrolyte leakage) caused by superoxide and hydrogen peroxide. Simultaneously, application of SA improved the net photosynthetic rate (84.55%) and water‐use efficiency (65.00%) of stressed plants in which these factors are connected to anatomical benefits, as verified by stomatal density, palisade and spongy parenchyma, combined with improved performance linked to photosystem II.
Wing morphology of a new Cretaceous praying mantis solves the phylogenetic jigsaw of early‐diverging extant lineages
Authors: Demers‐Potvin Alexandre V. , Larsson Hans C.E. , Cournoyer Mario , Béthoux Olivier
Published: January 2021

The extremely derived morphology and behaviour of extant praying mantises combined with a scarce record of fossil relatives introduce significant challenges to tracing their evolution from Palaeozoic stem‐dictyopterans. Extant members of Chaeteessidae, Mantoididae and Metallyticidae could be invaluable to resolving the mantodean tree, yet their inclusion in phylogenetic analyses led to conflicting hypotheses due to their highly disparate respective morphologies. In this contribution, we present Labradormantis guilbaulti gen. et sp.n., a new fossil species described from both fore‐ and hind‐wing imprints discovered in the Redmond Mine locality (Late Cretaceous, Cenomanian, Redmond Formation; Labrador, Canada). The examination of its hind‐wing AA2* supports the hypothesis that this structure, unique to Chaeteessidae among extant mantises, is a true vein and that its occurrence represents a plesiomorphy for Mantodea. A parsimony analysis including newly coded wing‐related characters further established that L. guilbaulti gen. et sp.n. displays a unique combination of plesiomorphic and apomorphic character states that situates it within the extinct family Baissomantidae. This dataset resolved the phylogenetic relationships of early‐diverging extant lineages as (Chaeteessidae (Mantoididae (Metallyticidae, Artimantodea))), and suggested that the Eocene Lithophotina floccosa Cockerell might be a close relative of extant metallyticids. It also indicated a trend towards increased modularity within mantis fore‐wings, in contrast with a trend towards increased morphological integration in their hind‐wings, both of which are potentially associated with improved flight performance for modern mantises. This study emphasizes the importance of fossils for resolving phylogenetic relationships and for introducing transitional phenotypes to infer ancient evolutionary trends of extant derived clades.
Phylogeny of the tribe Empoascini (Hemiptera: Cicadellidae: Typhlocybinae) based on morphological characteristics, with reclassification of the Empoasca generic group
Authors: Xu Ye , Dietrich Christopher H. , Zhang Ya‐Lin , Dmitriev Dmitry A. , Zhang Li , Wang Yi‐Mei , Lu Si‐Han , Qin Dao‐Zheng
Published: January 2021

A morphology‐based phylogenetic analysis of the tribe Empoascini (Hemiptera: Cicadellidae: Typhlocybinae) is presented for 58 of 83 formerly recognized genera based on 99 morphological characters of adults. The results support excluding the New World Beamerana generic group from Empoascini. The remaining genera of Empoascini were recovered as a monophyletic sister group of Dikraneurini. Previously recognized tribes Jorumini and Helionini are derived from within Empoascini and are considered synonyms of the latter tribe. Three previously recognized informal generic groups, the Empoasca group, Alebroides group and Usharia group were paraphyletic but the Ficiana group was recovered as monophyletic based on five synapomorphies. Genera previously placed in the Alebroides group represent at least six independent lineages, indicating that the hind wing character separating this group from the Empoasca group (CuA and MP veins free) is highly homoplasious. Empoasca (sensu lato) is also paraphyletic. Thus, twelve previously recognized subgenera of Empoasca are elevated to genus status and five species groups of Empoasca from the New World are recognized as separate new genera. Sikkimasca Dworakowska, 1993 is treated as synonym of Marolda Dworakowska, 1977 based on the phylogeny. Biogeographic analysis suggests that Empoascini most likely first evolved in the Oriental region and spread to other biogeographic realms more recently by multiple independent invasions.
Effect of Pitch Error on Static and Dynamic Characteristics of Hydrostatic Worm-Rack-Drive
Authors: Zhang Yongtao , Liu Yupeng , Deng Junjun , Song Rongxiang , Zhu Yingdan
Published: January 2021

Hydrostatic worm-rack-drive has obvious advantages on large-sized machine tools, and its performance is significantly affected by pitch errors. This paper theoretically researches the axial static and dynamic characteristics of hydrostatic worm-rack-drive, including the effects of the amplitude, period, and phase of pitch errors. Based on the expanded view of the helicoid of threads, a numerical calculation method is implemented where the Reynolds’ equation and flow continuity equation are solved simultaneously. The influence rule of pitch errors on pocket pressure, flow, axial fluid-film force, axial stiffness coefficient, and axial damping coefficient are discussed in detail, for providing beneficial guidance for the design and performance optimization of hydrostatic worm-rack-drive.
Effect of Uncertainty in the Balancing Weights on the Vibration Response of a High-Speed Rotor
Authors: Datz Janina , Karimi Mahmoud , Marburg Steffen
Published: January 2021

This work investigates how uncertainties in the balancing weights are propagating into the vibration response of a high-speed rotor. Balancing data are obtained from a 166-MW gas turbine rotor in a vacuum balancing tunnel. The influence coefficient method is then implemented to characterize the rotor system by a deterministic multi-speed and multi-plane matrix. To model the uncertainties, a non-sampling probabilistic method based on the generalized polynomial chaos expansion (gPCE) is employed. The uncertain parameters including the mass and angular positions of the balancing weights are then expressed by gPCE with deterministic coefficients. Assuming predefined probability distributions of the uncertain parameters, the stochastic Galerkin projection is applied to calculate the coefficients for the input parameters. Furthermore, the vibration amplitudes of the rotor response are represented by appropriate gPCE with unknown deterministic coefficients. These unknown coefficients are determined using the stochastic collocation method by evaluating the gPCE for the system response at a set of collocation points. The effects of individual and combined uncertain parameters from a single and multiple balancing planes on the rotor vibration response are examined. Results are compared with the Monte Carlo simulations, showing excellent agreement.
Forced Convective Flow of Bingham Plastic Fluids in a Branching Channel With the Effect of T-Channel Branching Angle
Authors: Maurya Anamika , Tiwari Naveen , Chhabra R. P.
Published: January 2021

This work aims to explore the T-channel momentum and heat transfer characteristics with the combined effect of Bingham plastic fluids (0.01 ≤ Bn ≤ 20) behavior and geometrical variation in terms of branching angle (30 deg ≤ α ≤ 90 deg). The problem has been solved over a wide range of Reynolds number (50 ≤ Re ≤ 300) and Prandtl number (10 ≤ Pr ≤ 50). For the momentum flow, qualitative and quantitative features are analyzed in terms of streamlines, structure of yielded/unyielded regions, shear rate contours, plug width and length variation, and local pressure coefficient. These features have been represented in terms of isotherm patterns, temperature profile, Nusselt number, and its asymptotic value for heat transfer characteristics. The recirculating flows have been presented here in the vicinity of T-junction, which promote mixing and heat transfer. Broadly, the size of this zone bears a positive dependence on Re and α. However, fluid yield stress tends to suppress it. The critical Reynolds and Bingham numbers were found to be strong functions of the pertinent parameters like α. The inclination angle exerts only a weak effect on the yielded/unyielded regions and on the recirculation length of main branch. Results show a strong relationship of the plug width and length with key parameters and branches. The Nusselt number exhibits a positive relationship with α, Bn, and Re but for lower Pr in the T-junction vicinity for both branches. Such length indicates the required optimum channel length for thermal mixing.
Numerical Modeling of Freestream Turbulence Decay Using Different Commercial Computational Fluid Dynamics Codes
Authors: Sarkar Dwaipayan , Savory Eric
Published: January 2021

This work models the spatial decay of freestream turbulence using three different commercial computational fluid dynamics (CFD) codes: Fluent, star-ccm+, and cfx. The two-equation shear stress transport k–ω (SST-k–ω) steady Reynolds-averaged-Navier–Stokes (RANS) model was used, within each of these three different commercial codes, and the modeling variations were analyzed. Comparison of the results from the SST-k–ω model with experiments and large eddy simulation (LES) (carried out using star-ccm+) were also made, which reveal that all the commercial CFD codes demonstrate either a higher or slower rate of spatial turbulent kinetic energy (TKE) decay. Attempts were then made to unify the resultant modeling approach between these three CFD tools, by careful manipulation of the inlet boundary conditions and subsequent fine-tuning of the SST-k–ω model constant (β∞∗). The results obtained not only displayed uniformity among the three CFD codes but also demonstrated a much better agreement to the experiments and the LES results. Thereafter, the optimized model coefficient (β∞∗) was integrated with the three-equation k–kl–ω transition model to examine its applicability in modeling a turbulent boundary layer flow over a flat plate with low incoming turbulence. The results showed good agreement with the theoretical boundary layer correlations, with correct prediction of the transition location. The findings from this study can be used as a suitable modeling method to accurately model the effects of freestream turbulence on bluff-body and boundary layer flows.
A Comparison of Different Approaches to Estimate the Efficiency of Wells Turbines
Authors: Licheri Fabio , Cambuli Francesco , Puddu Pierpaolo , Ghisu Tiziano
Published: January 2021

Wells turbines are among the most interesting power takeoff devices used in oscillating water column (OWC) systems for the conversion of ocean-wave energy into electrical energy. Several configurations have been studied during the last decades, both experimentally and numerically. Different methodologies have been proposed to estimate the efficiency of this turbine, as well as different approaches to evaluate the intermediate quantities required. Recent works have evaluated the so-called second-law efficiency of a Wells turbine, and compared it to the more often used first-law efficiency. In this study, theoretical analyses and numerical simulations have been used to demonstrate how these two efficiency measures should lead to equivalent values, given the low pressure ratio of the machine. In numerical simulations, small discrepancies can exist, but they are due to the difficulty of ensuring entropy conservation on complex three-dimensional meshes. The efficiencies of different rotor geometries are analyzed based on the proposed measures, and the main sources of loss are identified.
Comparative Analysis of Temperature Field Model and Design of Cooling System Structure Parameters of Submersible Motor
Authors: Zhang Qi , Li Zeng-liang , Dong Xiang-wei , Liu Yan-xin , Yu Ran
Published: January 2021

The reliability of submersible motors is directly related to the operational life of offshore oil-gas resources exploration and development equipment, crude oil production, and drilling costs. Temperature field model and coupling mode are the key factors for accurate analysis of cooling system. First, considering different equivalent modes of convective heat transfer of housing surface, two temperature field models are established using the finite volume method (FVM). Second, considering the influence of temperature and magnetic field, the coupling mode between heat loss (HL) and temperature of submersible motor is analyzed, and the importance of oil friction loss and copper loss as variables is pointed out. Considering the influence relationship among the components of the cooling system, the coupling mode between the radiator temperature field and the cooling system internal flow field is obtained. For a simulated circulation flow, the necessity of rotor iron loss calculation under the orthogonal decomposition correction model and rotor loss analysis is explained. Finally, the design procedure of the cooling system is proposed to obtain the design range between the structural parameters of the radiator and the circulation flow. Through the analysis of the influence factors of the cooling system, the matching mode of the same structural parameters under the two models is determined. These models are experimentally validated, and a more reasonable model is obtained under the proposed coupling mode in this paper, which can provide necessary insights for future research on submersible motor cooling systems.
Control of Boiling Instabilities in a Two-Phase Pumpless Loop Using Water-Alcohol Mixtures
Authors: Bhagat Ankit , Ghaisas Gautam , Mathew John , Krishnan Shankar
Published: January 2021

The mitigation of boiling instabilities by using water-alcohol mixtures as coolants in a two-phase pumpless loop is experimentally investigated. Water-miscible alcohol, namely, 2-propanol, is added to water in quantities of 0.05, 0.1, and 0.2 mol fractions to reduce the bubble departure diameters. Boiling experiments are carried out in the pumpless loop involving a copper-based split-flow microchannel evaporator. Two-phase flow stability and heat transfer performance are compared between pure water and 2-propanol-water mixtures. Temperature measurements at the evaporator inlet, evaporator outlet, and condenser inlet show a considerable reduction in fluctuations when the binary mixtures are used as coolants. Therefore, the addition of a small amount of alcohol to water is proposed as a simple technique to control two-phase flow instabilities as against complex geometry modification to the evaporator, often studied in the literature. The pumpless loop with water-alcohol mixtures is a viable thermal management solution for power electronic devices that involve time-varying workloads.
Anemone shows mechanism of rapid evolution
Authors: Pennisi Elizabeth
Published: January 2021

Single genetic switch converts stinging cells into sticky ones that cling to surfaces.
Pandemic could mark ‘turning point’ for Chinese science
Authors: Normile Dennis
Published: January 2021

Despite missteps and government control, early findings guided other countries' fight against the coronavirus.
COVID-19 measures also suppress flu—for now
Authors: Servick Kelly
Published: January 2021

In downside, trend could weaken immunity and complicate vaccine formulation.
Response to Comment on “Boosted molecular mobility during common chemical reactions”
Authors: Wang Huan , Park Myeonggon , Dong Ruoyu , Kim Junyoung , Cho Yoon-Kyoung , Tlusty Tsvi , Granick Steve
Published: January 2021

Günther
et al
. report that their control experiment using randomized magnetic field gradient sequences disagreed with findings we had reported using linear gradients. However, we show that measurements in our laboratory are consistent using both methods.
Structure of a transcribing RNA polymerase II–U1 snRNP complex
Authors: Zhang Suyang , Aibara Shintaro , Vos Seychelle M. , Agafonov Dmitry E. , Lührmann Reinhard , Cramer Patrick
Published: January 2021

A tight couple makes messenger RNAs

Gene expression in eukaryotes first requires transcription of DNA to an RNA copy and then splicing to form the final, processed messenger RNA (mRNA). Zhang
et al.
investigated how gene transcription and RNA splicing are physically coupled. Using cryo–electron microscopy, they resolved the molecular structure of a complex of the transcription enzyme RNA polymerase II with part of the splicing machinery, the U1 small nuclear ribonucleoprotein particle. The results provide important details for our understanding of coupled mRNA production.

Science
, this issue p.
305
From nuclear clusters to neutron stars
Authors: Hen Or
Published: January 2021

Measurements of a cluster formation in nuclear “skins” can improve neutron star models
Fighting the good fight
The New Climate War: The Fight to Take Back Our Planet
Michael E. Mann
PublicAffairs, 2021. 272 pp.
Authors: Hollis Adrienne
Published: January 2021

Fossil fuel advocates may have added strategic inaction to their arsenal, but there is reason for climate optimism
Correlation of SARS-CoV-2 Nucleocapsid Antigen and RNA Concentrations in Nasopharyngeal Samples from Children and Adults Using an Ultrasensitive and Quantitative Antigen Assay
Authors: Pollock Nira R. , Savage Timothy J. , Wardell Hanna , Lee Rose A. , Mathew Anu , Stengelin Martin , Sigal George B.
Published: January 2021

Diagnosis of COVID-19 by PCR offers high sensitivity, but the utility of detecting samples with high cycle threshold (

C
T

) values remains controversial. Currently available rapid diagnostic tests (RDTs) for SARS-CoV-2 nucleocapsid antigens (Ag) have sensitivity well below PCR.
Experimental Reptarenavirus Infection of
Boa constrictor
and
Python regius
Authors: Hetzel U. , Korzyukov Y. , Keller S. , Szirovicza L. , Pesch T. , Vapalahti O. , Kipar A. , Hepojoki J.
Published: January 2021

In the present study, we experimentally infected pythons and boas with reptarenavirus via either intraperitoneal injection or tracheal instillation. The aims were to experimentally induce boid inclusion body disease (BIBD) and to develop an animal model for studying disease transmission and pathogenesis.
Effect of seeding date on winter canola (Brassica napus L.) yield and oil quality in southern Ontario
Authors: Page Eric R. , Meloche Sydney , Moran Meghan , Caldbeck Brian , Barthet Véronique
Published: January 2021

Winter canola or winter oilseed rape (Brassica napus L.) is not commonly grown in Canada. While winter oilseed rape is the dominant growth form in Europe, Canadian canola production is dominated by spring types in western Canada. Research conducted in the 1980s indicated that the environmental conditions in southern Ontario are well suited to the production of winter canola. Since then, however, interest in the crop has ebbed, and little to no research has been conducted on the agronomic issues that potentially limit its adoption in the province. The objective of this research was to identify an optimal seeding date for winter canola in southern Ontario. Three winter canola hybrids were evaluated across five seeding dates, ranging from early September to late October. The results established the first two weeks of September as the optimal seeding period for winter canola in southern Ontario. Seeding winter canola during this period, such that greater than 600 growing degree days could be accumulated before the first fall frost, not only reduced winterkill to approximately 20%, but also maximized yield potential and ensured optimal oil quality. Winter canola showed great potential for production in southern Ontario, and its addition to current crop rotations would diversify and enhance crop production practices in this portion of the province.
Activation cross section data of deuteron induced nuclear reactions on rubidium up to 50 MeV
Authors: Tárkányi Ferenc , Hermanne Alex , Ditrói Ferenc , Takács Sándor , Ignatyuk Anatolij V. , Spahn Ingo , Spellerberg Stephan
Published: January 2021

Activation cross sections of the $$^{\mathrm {nat}}\hbox {Rb (d,xn)}^{87\mathrm {m,85m,85g,83,82}}\hbox {Sr}$$

nat

Rb

(d,xn)

87

m
,
85
m
,
85
g
,
83
,
82

Sr

, $$^{\mathrm {nat}}\hbox {Rb(d,x)}^{\mathrm {86,84,83,82m}}\hbox {Rb}$$

nat

Rb(d,x)

86
,
84
,
83
,
82
m

Rb

and $$^{\mathrm {nat}}\hbox {Rb(d,x)}^{85\mathrm {m}}\hbox {Kr}$$

nat

Rb(d,x)

85
m

Kr

nuclear reactions have been measured for the first time through an activation method combining the stacked foil irradiation technique and gamma-ray spectrometry. The provided cross sections from the present investigation are all new, in such a way contribute to the completeness of the experimental database. The experimental cross sections were compared with the theoretical prediction in the TENDL-2019 TALYS based library and with our calculation using ALICE-D and EMPIRE-D model codes in order the improve their predictivity. Thick target production yields were calculated form the new cross sections for all investigated radioisotopes. Practical applications of the results are shortly discussed.
Thick brane structures in generalized hybrid metric-Palatini gravity
Authors: Rosa João Luís , Ferreira D. A. , Bazeia Dionisio , Lobo Francisco S. N.
Published: January 2021

In this work, we study 5-dimensional braneworld scenarios in the scalar-tensor representation of the generalized hybrid metric-Palatini gravitational theory. We start by considering a model for a brane supported purely by the gravitational scalar fields of the theory and then consider other distinct cases where the models are also supported by an additional matter scalar field. We investigate the stability of the gravity sector and show that the models are all robust against small fluctuations of the metric. In particular, in the presence of the additional scalar field, we find that the profile of the gravitational zero mode may be controlled by the parameters of the model, being also capable of developing internal structure.