bluuebunny/crossref_metadata_2025_split huggingface dataset:
Investigation of an X-band Cerenkov-type high power microwave oscillator driven by sheet electron beam
Authors: Zeng Fanzheng , Du Guangxing , Qian Baoliang , Cai Hao , Wang Junting 
Published: May 2021

An X-band Cerenkov-type high power microwave (HPM) oscillator driven by a sheet electron beam is proposed and designed in this paper. In order to improve the efficiency of simulation optimization, a research method is proposed in which the large caliber coaxial Cerenkov-type HPM oscillator is taken as an initial model, which is equivalent to that of the planar slow-wave structure (SWS) by using the similarity between the planar SWS and the large caliber coaxial SWS. In addition, the effectiveness of the equivalent method is verified from the geometric structure, the field distribution of the operating mode, dispersion characteristics, and the preliminary particle simulation results of two devices. Based on the results of an X-band large caliber coaxial Cerenkov-type HPM oscillator, an X-band Cerenkov-type HPM oscillator driven by a sheet electron beam is investigated by the 3D particle-in-cell code. The simulation results show that the power conversion efficiency can reach 26.1% at the frequency of 11.9 GHz with the output power of 0.3 GW, while the sheet electron beam has the energy of 486 kV and it carries the current of 2.4 kA conducted by the magnetic field of 2.5 T.
Defect and dopant properties in CaMnO3
Authors: Kuganathan Navaratnarajah , Chroneos Alexander 
Published: May 2021

CaMnO3-based ceramics have been the subject of considerable research due to their potential application in solid oxide fuel cells, thermoelectric generators, and catalysis. The computational modeling technique based on the classical pair-wise potentials has allowed atomic-scale insights into the defect chemistry, diffusion of Ca2+ and O2− ions, and solution of various dopants in this material. The Ca/Mn anti-site was found to be the most favorable intrinsic defect suggesting disorder, which would be sensitive to synthesis conditions. The second most favorable disorder in CaMnO3 involves loss of CaO, resulting in calcium and oxygen vacancies, which in turn can promote vacancy mediated self-diffusion. The activation energy for oxygen migration (1.25 eV) is much lower than that for calcium (4.42 eV). Favorable isovalent dopants on the Ca and Mn sites were found to be Fe2+ and Ge4+, respectively. The formation of O vacancies can be facilitated by doping of single dopants Fe2+ and Al3+ on the Mn site. Dual dopants Ni–Fe and Al–Ga on the Mn site can also facilitate the introduction of oxygen vacancies required for the vacancy assisted oxygen diffusion.
Predicted half-metallicity and ferromagnetism in the Fe (III) doped BaZrO3 perovskite: A theoretical insight
Authors: Nisar Mohammad , Ma Yecheng , Khan Shahid , Khatoon Rabia , Xu Gang , Liu Yong , Han Gaorong 
Published: May 2021

The variance in the magnetoelectric behavior of BaZrO3 owing to the doping of Fe (III) on the Zr-site has been studied based on density functional calculations. We can predict the structural parameters, electronic structure, and ferromagnetic properties of BaFexZr1−xO3 precisely deprived of considering any strong correlation effect in the calculations. The equilibrium structural parameters are accounted to be in concurrence with the former theoretical and experimental investigations. It is observed that the structural phase remained semiconducting cubic (Pm-3m) up to 12.5% of Fe content and transformed to a conducting tetragonal phase (P4/mmm) beyond that. Spin-polarized density of states and band-structure calculations have probed that pristine BaZrO3 is a wide-bandgap semiconductor and in a nonmagnetic state. The ground-energy-state of Fe3+ doped BaZrO3 compounds varies from half-metal to metal in a ferromagnetic state. In particular, the present calculations have correctly predicted half-metallicity in BaFexZr1−xO3 when doping concentrations were 12.5% and 25%. The half-metallic gap ΔHM, which is the minimum of the lowest energy level of minority spin conduction bands relative to the Fermi level, and the absolute values of the topmost energy level of minority spin valence bands are estimated to be 0.55 eV in BaFe0.25Zr0.75O3 and 0.44 eV in BaFe0.5Zr0.5O3.
Molecular dynamics investigation of the slip flow liquid–solid interfacial thermal conductance
Authors: Wang Zhenyu , Sun Shangwei , Cui Yifan , Ran Ran , Zhao Yongzhi 
Published: May 2021

With the integrated high-power device packaging structure rapidly developing, the embedded heat dissipation architectures are challenged by the local micro-/nanoscale massive heat flux. The slip flow molecular dynamics models were established to explore the liquid–solid interfacial thermal conductance. With stepwise declining shear forces (0.032 pN/200, 0.024 pN/200, and 0.016 pN/200 ps, respectively), the slip flow [the slip shear velocity is Si: (125.43 ± 0.92 m/s), graphite: (142.43 ± 1.92 m/s), and Cu: (180.93 ± 3.42 m/s), respectively] water–solid interfacial thermal conductance of different materials [Si: (8.11 ± 0.1) × 107 W/m2 K, graphite: (10.18 ± 0.1) × 107 W/m2 K, and Cu: (17.97 ± 0.1) × 107 W/m2 K] can be calculated. The rationality of the calculated values can be verified in the literature. The slip flow water–solid interfacial thermal conductance values are about 0.5 times higher than the static ones. It can be significantly affected by the slip shear velocity. The slip shear velocity increasing about five times can enhance the interfacial thermal conductance two times. From the water layer density distribution, it is found that the dependence of interfacial thermal conductance on velocity slip relies more on the dynamical properties than on the fluid structure. This molecular dynamics model provides an operative methodology to investigate the slip flow liquid–solid interfacial heat transfer for the various embedded cooling surfaces.
Delineating the heterogeneity of matrix-directed differentiation toward soft and stiff tissue lineages via single-cell profiling
Authors: Brielle Shlomi , Bavli Danny , Motzik Alex , Kan-Tor Yoav , Sun Xue , Kozulin Chen , Avni Batia , Ram Oren , Buxboim Amnon 
Published: May 2021

Significance
The clinical utility of mesenchymal stromal/stem cells (MSCs) in mediating immunosuppressive effects and supporting regenerative processes is broadly established. However, the inherent heterogeneity of MSCs compromises its biomedical efficacy and reproducibility. To study how cellular variation affects fate decision-making processes, we perform single-cell RNA sequencing at multiple time points during bipotential matrix-directed differentiation toward soft- and stiff tissue lineages. In this manner, we identify distinctive MSC subpopulations that are characterized by their multipotent differentiation capacity and mechanosensitivity. Also, whole-genome screening highlights TPM1 as a potent mechanotransducer of matrix signals and regulator of cell differentiation. Thus, by introducing single-cell methodologies into mechanobiology, we delineate the complexity of adult stem cell responses to extracellular cues in tissue regeneration and immunomodulation.
Increasing second language production with gestures
Authors: Wilks-Smith Naomi 
Published: May 2021

Abstract
Gesture-based methods of teaching second languages have increasingly attracted interest. Previous research has linked gesture with language learning; however, little is known about the impact on learners’ language production, and even less is known about the impact of the unique Intentional Teaching Gestures (ITG) used in many second language programs. This empirical case study investigated the impact of learning with ITG on the oral language production of 170 primary school students learning Japanese as a second language in Australia, using a quasi-experimental approach with Story Re-tell methodology. Findings identify that viewing ITG increased learners’ language retrieval and quantity of oral language produced and highlight the pedagogical value of viewing ITG as a scaffolding tool.
Urocystis agropyri (flag smut of wheat).
Authors:   USA, USDA-ARS
Published: May 2021

Abstract

U. agropyri causes flag smut on leaves of species in the family Poaceae. As a pathogen of grasses, it appears to have a wide host range (Mordue and Waller, 1981) and a worldwide distribution (UK CAB International, 1991). However, some authorities do not include the pathogen on wheat [Triticum aestivum], identified as Urocystis tritici, within U. agropyri. Rossman et al. (2006) place U. agropyri in the category of a "Threat to Major Crop Plants" and wheat and wheat straw imports are restricted in North America (Anon., 2005; CFIA, 2008). If the widespread species includes the wheat pathogen, then it is already present on all continents with agriculture and in major wheat-growing areas (Purdy, 1965), so it has already been introduced and may be difficult to exclude from additional areas. Both smuts are seed- and soil-borne, causing systemic infections that can be perennial in weeds and graminaceous crops, including turfgrasses. The spore balls are windborne (Purdy, 1965) and prevention of spread among wild grasses on land is not amenable to control.
The relation between the radii and the densities of magnetic skyrmions
Authors: Bo Yu-Jiao , Li Wen-Wen , Guo Yu-Chen , Yang Ji-Chong 
Published: May 2021

Abstract
Compared with the traditional magnetic bubble, a skyrmion has a smaller size, and better stability and therefore is considered as a very promising candidate for future memory devices. When skyrmions are manipulated, erased and created, the density of skyrmions can be varied, however the relationship between the radii and the densities of skyrmions needs more exploration. In this paper, we study this problem both theoretically and by using the lattice simulation. The average radius of skyrmions as a function of material parameters, the strength of the external magnetic field and the density of skyrmions is obtained and verified. With this explicit function, the skyrmion radius can be easily predicted, which is helpful for the future study of skyrmion memory devices.
Prevalence of initial orthostatic hypotension in older adults: a systematic review and meta-analysis
Authors: Tran Jennifer , Hillebrand Sarah L , Meskers Carel G M , Iseli Rebecca K , Maier Andrea B 
Published: May 2021

Abstract

Background
Initial orthostatic hypotension (OH) is a clinical syndrome of exaggerated transient orthostasis associated with higher risks of falls, frailty and syncope in older adults.

Objective
To provide a prevalence estimate of initial OH in adults aged 65 years or older.

Methods
Literature search of MEDLINE (from 1946), Embase (from 1947) and Cochrane Central Register of Controlled Trials was performed until 6 December 2019, using the terms ‘initial orthostatic hypotension’, ‘postural hypotension’ and ‘older adults’. Articles were included if published in English and participants were 65 years or older. Random effects models were used for pooled analysis.

Results
Of 5,136 articles screened, 13 articles (10 cross-sectional; 3 longitudinal) reporting data of 5,465 individuals (54.5% female) from the general (n = 4,157), geriatric outpatient (n = 1,136), institutionalised (n = 55) and mixed (n = 117) population were included. Blood pressure was measured continuously and intermittently in 11 and 2 studies, respectively. Pooled prevalence of continuously measured initial OH was 29.0% (95% CI: 22.1–36.9%, I2 = 94.6%); 27.8% in the general population (95% CI: 17.9–40.5%, I2 = 96.1%), 35.2% in geriatric outpatients (95% CI: 24.2–48.1%, I2 = 95.3%), 10.0% in institutionalised individuals (95% CI: 2.4–33.1%, I2 = 0%) and 21.4% in the mixed population (95% CI: 7.0–49.6, I2 = 0%). Pooled prevalence of intermittently measured initial OH was 5.6% (95% CI: 1.5–18.9%, I2 = 81.1%); 1.0% in the general population (95% CI: 0.0–23.9%, I2 = 0%) and 7.7% in geriatric outpatients (95% CI: 1.8–27.0%, I2 = 86.7%).

Conclusion
The prevalence of initial OH is high in older adults, especially in geriatric outpatients. Proper assessment of initial OH requires continuous blood pressure measurements.
Social Networks in an Assisted Living Community: Correlates of Acquaintance and Companionship Ties Among Residents
Authors: Mauldin Rebecca L , Fujimoto Kayo , Wong Carin , Herrera Sarah , Anderson Keith A 
Published: May 2021

Abstract

Objectives
Social relationships are important for older adults’ well-being, including those who live in assisted living (AL) communities. This study explores coresident networks within an AL community and identifies factors associated with residents’ social ties.

Methods
Acquaintance and companionship networks within the community are described using cross-sectional survey data (N = 38). We use inferential network statistical methods to estimate parameters for factors associated with residents’ acquaintance and companionship ties.

Results
Residents reported an average of 10 acquaintances and almost 4 companionships with other residents in the sample. The likelihood a resident had an acquaintance was associated with higher levels of cognitive functioning (p &lt; .05), higher levels of physical limitations (p &lt; .01), living in the AL community for a longer time (p &lt; .01), and less frequent contact with outside family and friends (p &lt; .05). Acquaintances were more likely between residents who moved in around the same time as each other (p &lt; .01), lived on the same floor (p &lt; .001), or had similar levels of physical limitations (p &lt; .05). Companionships were more likely to be reported by male residents (p &lt; .05) and residents with higher levels of cognitive functioning (p &lt; .05) or depressive symptoms (p &lt; .05). Longtime residents were more popular as companions (p &lt; .01). Companionships were more likely between residents who lived on the same floor (p &lt; .001) or were similar in age (p &lt; .01).

Discussion
This research contributes to the literature of older adults’ nonkin social relationships by providing detailed descriptions of the acquaintance and companionship networks within an AL community, quantifying correlates of residents’ social ties, and distinguishing between acquaintances and companions.
Application of the hollow fibre infection model (HFIM) in antimicrobial development: a systematic review and recommendations of reporting
Authors: Sadouki Zahra , McHugh Timothy D. , Aarnoutse Rob , Ortiz Canseco Julio , Darlow Christopher , Hope William , van Ingen Jakko , Longshaw Christopher , Manissero Davide , Mead Andrew , Pelligand Ludovic , Phee Lynette , Readman John , Ruth Mike M. , Standing Joseph F. , Stone Neil , Wey Emmanuel Q. , Kloprogge Frank 
Published: May 2021

AbstractObjectivesThis systematic review focuses on the use of the in vitro hollow fibre infection model (HFIM) for microbial culture. We summarize the direction of the field to date and propose best-practice principles for reporting of the applications.MethodsSearches in six databases (MEDLINE®, EMBASE®, PubMed®, BIOSIS®, SCOPUS® and Cochrane®) up to January 2020 identified 129 studies meeting our inclusion criteria. Two reviewers independently assessed and extracted data from each publication. The quality of reporting of microbiological and technical parameters was analysed.ResultsForty-seven out of 129 (36.4%) studies did not report the minimum pharmacokinetic parameters required in order to replicate the pharmacokinetic profile of HFIM experiments. Fifty-three out of 129 (41.1%) publications did not report the medium used in the HFIM. The overwhelming majority of publications did not perform any technical repeats [107/129 (82.9%)] or biological repeats [97/129 (75.2%)].ConclusionsThis review demonstrates that most publications provide insufficient data to allow for results to be evaluated, thus impairing the reproducibility of HFIM experiments. Therefore, there is a clear need for the development of laboratory standardization and improved reporting of HFIM experiments.
Improving outcomes and antibiotic stewardship (IOAS) for patients with Gram-positive bloodstream infections through use of rapid testing: a quasi-experimental multicentre study of the Accelerate PhenoTest™ BC Kit
Authors: MacVane Shawn H. , Bhalodi Amira A. , Dare Ryan K. , Rosenbaum Eric R. , Wolfe Kaleb , Ford Bradley , Ince Dilek , Kinn Patrick , Percival Kelly M. , Humphries Romney M. 
Published: May 2021

AbstractBackgroundData from the Improving Outcomes and Antibiotic Stewardship for Patients with Bloodstream Infections: Accelerate PhenoTest™ BC Kit (AXDX) Registry Study were analysed to determine the impact of rapid organism identification and antimicrobial susceptibility testing (AST) for Gram-positive bacteraemia.Patients and methodsThis multicentre, quasi-experimental study evaluated clinical and antimicrobial stewardship metrics following the implementation of AXDX. Data from hospitalized patients with bacteraemia were compared between groups, one that underwent testing on AXDX (post-AXDX) and one that underwent traditional identification and AST (pre-AXDX). An analysis of patients with Gram-positive bacteraemia was performed. The primary outcome was time to optimal therapy (TTOT). Secondary outcomes included time to first antibiotic modification (overall and Gram-positive), duration of unnecessary MRSA coverage, incidence of adverse events, length of stay and mortality.ResultsA total of 219 (109 pre-AXDX, 110 post-AXDX) patients with Gram-positive bacteraemia were included. Median TTOT was 36.3 h (IQR, 16.9–56.7) in the pre-AXDX group and 20.4 h (IQR, 7.5–36.7) in the post-AXDX group (P = 0.01). Compared with pre-AXDX, median time to first antibiotic modification (29.1 versus 15.9 h; P = 0.002), time to first Gram-positive antibiotic modification (33.2 versus 17.2 h; P = 0.003) and median duration of unnecessary MRSA coverage (58.4 versus 29.7 h; P = 0.04) were reduced post-AXDX. A trend towards decreased acute kidney injury (24% versus 13%; P = 0.06) was observed in the post-AXDX group. Groups did not differ in other secondary outcomes.ConclusionsImplementation of AXDX testing for patients with Gram-positive bacteraemia shortened the TTOT and reduced unnecessary antibiotic exposure due to faster antibiotic modifications.
Characterization of the Complete Chloroplast Genome of Buddleja lindleyana
Authors: Liu Shanshan , Feng Shiyin , Huang Yuying , An Wenli , Yang Zerui , Xie Chunzhu , Zheng Xiasheng 
Published: May 2021

Abstract

Background
Buddleja lindleyana Fort., which belongs to the Loganiaceae with a distribution throughout the tropics, is widely used as an ornamental plant in China. There are several morphologically similar species in the genus Buddleja, but the lack of comprehensive molecular and phylogenetic studies makes it difficult to distinguish related species, which hinders further studies of this genus.

Objective
Using molecular biology techniques to sequence and analyze the complete chloroplast (cp) genome of B. lindleyana.

Methods
After sequencing of the genomic DNA using next-generation sequencing, a series of bioinformatics software were used to assemble and analyze the molecular structure of the cp genome of B. lindleyana.

Results
The complete cp genome of B. lindleyana is a circular 154 487-bp-long molecule with a GC (Guanine and Cytosine) content of 38.1%. It has a quadripartite structure, including a LSC region (85 489 base pair (bp)), a small single-copy region (17 898 bp), and a pair of inverted repeat regions (25 550 bp). A total of 133 genes were identified in this genome, including 86 protein-coding genes, 37 tRNA (transfer Ribonucleic Acid) genes, eight rRNA (ribosomal Ribonucleic Acid) genes, and two pseudogenes.

Conclusion
These results suggest that the B. lindelyana cp genome could be used as a potential genomic resource to resolve the phylogenetic positions and relationships of Loganiaceae, and will offer valuable information for future research in the identification of Buddleja species and will conduce to genomic investigations into these species.

Highlights
This paper study the B. lindelyana cp genome and it's structural characteristics, and analyze the phylogeny of Loganiaceae.
Investigation of intra-day variability of gaseous measurements in sheep using portable accumulation chambers
Authors: O’ Connor Edel , McHugh Nóirín , Boland Tommy M , Dunne Eoin , McGovern Fiona M 
Published: May 2021

Abstract
Portable accumulation chambers (PAC) enable short-term spot measurements of gaseous emissions including methane (CH4), carbon dioxide (CO2), and oxygen (O2) consumption from small ruminants. To date the differences in morning and evening gaseous measurements in the PAC have not been investigated. The objectives of this study were to investigate: 1) the optimal measurement time in the PAC, 2) the appropriate method of accounting for the animal’s size when calculating the animal’s gaseous output, and 3) the intra-day variability of gaseous measurements. A total of 12 ewe lambs (c. 10 to 11 months of age) were randomly selected each day from a cohort of 48 animals over nine consecutive days. Methane emissions from the 12 lambs were measured in 12 PAC during two measurement runs daily, AM (8 to 10 h) and PM (14 to 16 h). Animals were removed from Perennial ryegrass silage for at least 1 h prior to measurements in the PAC and animals were assigned randomly to each of the 12 chambers. Methane (ppm) concentration, O2 and CO2 percentage were measured at 5 time points (T1 = 0.0 min, T2 = 12.5 min, T3 = 25.0 min, T4 = 37.5 min, and T5 = 50.0 min from entry of the first animal into the first chamber) using an Eagle 2 monitor. The correlation between time points T5-T1 (i.e., 50 min minus 0 min after entry of the animal to the chamber) and T4-T1 was 0.95, 0.92, and 0.77 for CH4, O2, and CO2, respectively (P &lt; 0.01). The correlation between CH4 and CO2 output and O2 consumption, calculated with live-weight and with body volume was 0.99 (P &lt; 0.001). The correlation between the PAC measurement recorded on the same animal in the AM and PM measurement runs was 0.73. Factors associated with CH4 production included: day and time of measurement, the live-weight of the animal and the hourly relative humidity. Results from this study suggest that the optimal time for measuring an animal’s gaseous output in the PAC is 50 min, that live-weight should be used in the calculation of gaseous output from an animal and that the measurement of an animal’s gaseous emissions in either the AM or PM does not impact on the ranking of animals when gaseous emissions are measured using the feeding and measurement protocol outlined in the present study.
Quantitation of Methamphetamine and Amphetamine in Postmortem Canine Tissues and Fluids
Authors: Buchweitz John P , Johnson Margaret , Wixson Margaret , Puschner Birgit 
Published: May 2021

Abstract
The production and use of the highly addictive stimulant methamphetamine are a serious public health problem in the USA and globally. Because of its increased popularity with recreational drug users, accidental or intentional poisoning incidents in companion animals have become an unavoidable scenario in veterinary medicine. We describe a case of methamphetamine poisoning in a 4-year-old female German Shepherd, with postmortem analytical quantitation of methamphetamine and its metabolite, amphetamine, in bodily tissues and fluids. Many tissues and bodily fluids can be tested to confirm methamphetamine exposure. More importantly, the higher concentrations found in stomach contents and liver, kidney and heart tissues suggest these are the most useful diagnostic specimens for postmortem confirmation of toxicosis in pets, especially in cases in which the source material is not available for testing or in cases with no postmortem evaluation.