bluuebunny/crossref_metadata_2025_split huggingface dataset:
Factors associated with mechanical ventilation in SARS‐CoV‐2 patients treated with high‐flow nasal cannula oxygen and outcomes
Authors: Leroux Xavier , Schock Maud , Augereau Olivier , Lessire Henry , Bouterra Charles , Belilita Lounis , Rerat Pierre , Alvarez Antonio , Martinot Martin , Gerber Victor 
Published: November 2021

AbstractFive percent of patients infected with SARS‐CoV‐2 require advanced respiratory support. The high‐flow nasal cannula oxygenotherapy (HFNCO) appears to be effective and safe to reduce the need for mechanical ventilation. However, the factors associated with HFNCO failure as well as the outcomes of patients receiving this noninvasive respiratory strategy remain unclear. Thus, we performed this study to determine factors leading to intubation of SARS‐CoV‐2 patients treated with HFNCO and patients’ outcomes. We retrospectively analyzed the medical charts of patients admitted in our ICU center for acute respiratory failure due to SARS‐CoV‐2 infection and who initially benefited from HFNCO, between September 1, 2020, and March 1, 2021. We included all adults patients who received HFNCO and compared two groups: those treated with HFNCO alone and those who failed HFNCO. Patients treated with HFNCO and secondarily limited to the use of mechanical ventilation were excluded from the analysis. Sixty‐nine patients were included, 33 were treated with HFNCO alone and 36 failed HFNCO. We found more patients with shock in the HFNCO failure group (p = 0.001). The mean IGSII score was higher in the HFNCO failure group (p < 0.001). The minimum PaO2/FiO2 was lower in the HFNCO failure group (p = 0.024). The length of stay in ICU was higher in the HFNCO failure group (p < 0.001). The mean duration of HFNCO before intubation was 1.77 days. Six‐week mortality was higher in the HFNCO failure group (p = 0.034). Ten patients had a complication during intubation. The HFNCO leads to reduce the intubation rate, the length of stay in ICU, and the mortality. Determining the factors associated with HFNCO failure is important to avoid complications following late intubation.
Analysis by real‐time PCR of five transport and conservation mediums of nasopharyngeal swab samples to COVID‐19 diagnosis in Santiago of Chile
Authors: Barrera‐Avalos Carlos , Luraschi Roberto , Vallejos‐Vidal Eva , Figueroa Maximiliano , Arenillas Esteban , Barría Daniela , Hernández Felipe , Mateluna Carlos , Mena Javier , Rioseco Claudia , Torrent Claudia , Vergara Claudio , Gutiérrez Gaby , Quiroz Javiera , Alarcón Javiera , Cartagena Julio , Cayunao Javiera , Mella‐Torres Andrea , Santibañez Álvaro , Tapia Sebastián , Undurraga Alejandro , Vargas Deborah , Wong Valentina , Inostroza‐Molina Ailen , Valdés Daniel , Imarai Mónica , Acuña‐Castillo Claudio , Reyes‐López Felipe E. , Sandino Ana M. 
Published: November 2021

AbstractDue to the COVID‐19 pandemic, many transport kits have been manufactured to preserve and transport nasopharyngeal swab samples (NPSs) from patients. However, there is no information on the performance of the different virus transport media (VTM) used in COVID‐19 diagnosis in the population of Santiago de Chile. We compared the RT‐qPCR amplification profile of five different viral transport kit mediums, including DNA/RNA Shield™, NAT, VTM‐N, Ezmedlab™, and phosphate‐buffered saline (PBS), for NPSs from Central Metropolitan Health Service, Santiago, Chile. The DNA/RNA Shield™ medium showed a better performance in terms of Cq and RFU values for the internal reference RNase P and viral ORF1ab probes. By contrast, the PBS transport medium registered higher Cq values for the viral and reference gene, compared to the other VTM. DNA/RNA Shield™ shows higher relative fluorescence units (RFUs) and lower Cq values for the reference gene. Collectively, our results suggest that the PBS medium could compromise the sample diagnosis because of its lower RT‐qPCR performance. The NAT, Ezmedlab and VTM‐N, and DNA/RNA Shield™ media show acceptable RT‐qPCR parameters and, consequently, seem suitable for use in COVID‐19 diagnosis.
The performance of water‐soluble fluoride transformation in soil–tea–tea infusion chain system and the potential health risk assessment
Authors: Sun Hua , Wen Bo , Wu Zichen , Xing Anqi , Xu Xiaohan , Chang Yali , Guo Guiyi , Wang Yuhua 
Published: November 2021

AbstractBACKGROUNDWater‐soluble fluoride (WS‐F) can be absorbed directly by tea plants from soil and comprises a major source of dietary F in tea consumers. To reveal the WS‐F accumulation in tea leaves and assess WS‐F health risks, 70 sets of samples including tea leaves at three maturity stages and corresponding topsoil were collected from Xinyang, China. The WS‐F contents in tea samples and pH values in soil samples were determined.RESULTSThe contents of WS‐F in tea leaves exhibited a positive correlation with leaf maturity. The contents of WS‐F in tea leaves showed a positive correlation with WS‐F contents in the soil as the soil pH value exceeds 5. All the bud with two leaves samples, 84.29% of the third to sixth leaves samples, and 78.57% mature leaves samples in 5‐min infusion tend to be no health threat. The leaching characteristics of WS‐F from tea leaves were influenced by the leaf maturity and soaking time.CONCLUSIONTaking measures to control pH and WS‐F concentration of plantations soil, as well as drinking tea infusion made from young leaves or reducing soaking time could decrease the WS‐F health risk. © 2021 Society of Chemical Industry.
RAFT Polymerization of 2‐(tert‐Butoxycarbonyloxy)Ethyl Methacrylate and Transformation to Functional Polymers via Deprotection and the Subsequent Polymer Reactions
Authors: Jing Chu , Osada Kaito , Kojima Chie , Suzuki Yasuhito , Matsumoto Akikazu 
Published: November 2021

AbstractReversible addition–fragmentation chain transfer (RAFT) polymerization of 2‐(tert‐butoxycarbonyloxy)ethyl methacrylate (BHEMA) is carried out using 4‐cyano‐4‐((dodecylsulfanylthiocarbonyl)sulfanyl)pentanoic acid as the RAFT agent. The polymers with a controlled molecular weight and polydispersity are produced when a large amount of the RAFT agent is used. The RAFT polymerization of isobutyl methacrylate is also carried out using poly(2‐(tert‐butoxycarbonyloxy)ethyl methacrylate) (PBHEMA) as the macro‐RAFT agent in order to synthesize diblock copolymers with a narrow molecular weight distribution. It is revealed that the control of the polymerization of BHEMA is achieved under limited polymerization conditions. Then, the acid‐catalyzed deprotection of tert‐butoxycarbonyloxy groups of PBHEMA is performed in the presence of trifluoroacetic acid at room temperature to obtain polymers with a hydroxy group in the side chain. The hydroxy‐containing polymers are further reacted with 2‐isocyanatoethyl acrylate and methacrylate to synthesize precursor polymers used for a thermally curing system.
Additive manufactured spherical resonator V‐band elliptical waveguide filter
Authors: Liu Wenbo , Huff Gregory 
Published: November 2021

AbstractThe design of an additively manufactured V‐band bandpass filter is proposed using spherical resonators with elliptical waveguides feeds. Compared with the traditional rectangular form, the curvilinear architecture seeks to mitigate corner radius effects in both the electromagnetic performance and additive manufacturing process. The filter and calibration components required for measurement are printed as single structures and then electroless silver plated using a closed‐loop bidirectional pump‐driven fluidic system. Simulated and measured results are provided.
A promising sustainable PHB‐ZnO composite for development of biodegradable filaments
Authors: Silva Nycolle G. S. , Zanini Noelle C. , Barbosa Rennan F. S. , de Souza Alana G. , Medeiros Simone F. , Rosa Derval S. , Mulinari Daniella R. 
Published: November 2021

AbstractThe development of new biodegradable composites with superior properties is an attractive approach to develop environmentally friendly materials with new potential applications. In this work, we prepared and characterized PHB filaments with different concentrations of ZnO particles (from 0.5 up to 16 wt%) to evaluate this mixture's effect on the physico‐chemical, thermal properties, and morphological biofilament characteristics. The FTIR and Raman results indicated a possible chemical interaction between the ZnO and PHB, altering the helical polymeric and crystalline structure. The ZnO particles increased the composites' thermal stability, mainly at higher filler contents, confirmed by Tonset and the thermal resistance index, associated with the interface between the particles and the PHB matrix. Also, DSC results indicated that higher ZnO contents increased the PHB amorphous characteristic, which facilitates its use as filaments. The microscopies allowed the evaluation of composites' morphology and indicated good filler dispersion and homogeneity, and the filament diameters were adequate to the FDM 3D printing technique. SEM‐EDS confirmed ZnO presence at filament structure, which probably stabilized the PHB matrix during the extrusion process and allowed the printing process for the PHB‐0.5%ZnO filaments into scaffolds, showing the potential application in additive manufacturing processes. These findings may expand PHB applications combining ZnO properties to develop functional and active materials for biomedical and packaging applications.
Extraction and characterization of natural cellulosic fiber from fragrant screw pine prop roots as potential reinforcement for polymer composites
Authors: Selvan Martin Thangaraj Gerald Arul , Binoj Joseph Selvi , Moses Jacob Thambi Evans Jebeen , Sai Nara Prem , Siengchin Suchart , Sanjay Mavinkere Rangappa , Liu Yucheng 
Published: November 2021

AbstractBiodegradable natural plant fiber isolated from the prop roots of fragrant screwpine (FSP) plant has been thoroughly studied as a potential replacement for artificial fiber in light weight bio‐based composite applications. Chemical, physical, Fourier transform infrared spectroscopy, X‐ray diffraction, scanning electron microscopy, differential scanning calorimetry, and thermo gravimetric studies were used to determine the appropriateness of FSP fiber for use as a novel reinforcement. FSP fibers were determined to have a density of 1.3852 g/cm3 and a diameter of 27–280 μm respectively. Good specific strength and bonding qualities are provided by a high cellulose content (73.10 wt%) and a low wax content (0.35 wt%). The tensile strength of raw FSP fiber was 915 ± 195 MPa, the young's modulus was 33 ± 12 GPa, and the average strain to failure rate was 4.59 ± 2.17%. Thermal analysis (TG and DTG) confirmed FSP fiber's thermal stability up to 235°C. The findings revealed that FSP fiber (FSPF) is an excellent alternative for constructing polymer‐based bio‐composites and other high‐value products with both technical and environmental requirements.
Effects of Hochuekkito, a traditional Japanese medicine (Kampo), on reproduction of aging female mice
Authors: Vo Kim Cat Tuyen , Sato Yorino , Kawagoe Yuta , Kawamura Kazuhiro 
Published: November 2021

AbstractPurposeTo determine the potentials of Hochuekkito (HET) treatment for aging infertility.MethodsMice at 36 weeks of age were fed without (control, n = 40) or with low (100 mg/kg/day, n = 24) and high (1000 mg/kg/day, n = 38) doses of HET for 12 weeks. Aging animals at 48 weeks of age were used for in vitro fertilization‐embryo transfer (IVF‐ET), and their ovaries were subjected to histological and quantitative inflammation analyses.ResultsHET administration decreased transcript levels of ovarian inflammatory markers, interleukin 6 (IL‐6), IL‐1β, tumor necrosis factor (TNF)‐α, and interferon‐gamma (IFN‐γ) but suppressed ovulation rates and the number of ovulated oocytes in aging mice. Furthermore, HET treatment decreased the rates of oocytes maturation and fertilization and the cumulus‐cell expression of TNF‐α‐induced protein 6 and epidermal growth factor receptor. After IVF‐ET, no improvement of declined live offspring rate by aging was achieved by HET administration, although there were no adverse effects on embryo development and implantation as well as gross morphology and bodyweight of pups.ConclusionPresent study indicated HET treatment interfered with ovulation and fertilization in aging mice without affecting ovarian follicle development. No improvement on the age‐associated decline of live offspring rate and follicle development was achieved after HET treatment.
Copper(II) Acetylacetonate/Tetrabutylammonium Hydrogen Sulfate: A New System for Decarboxylation of Aromatic Carboxylic Acids under Amine‐Free Conditions
Authors: Yousefi Reza , Hosseini Abolfazl , Tajbakhsh Mahmood 
Published: November 2021

AbstractA new system for decarboxylation of aromatic carboxylic acids under amine‐free conditions has been developed. In situ generated copper nanoparticles (Cu NPs) stabilized by tetrabutylammonium hydrogen sulfate (TBAHS) were found to catalyze the decarboxylation of aromatic carboxylic acids under amine‐free conditions. Ortho‐substituted benzoic acids bearing electron‐deficient and electron‐rich groups were effectively decarboxylated under these conditions whereas meta‐ and para‐substituted benzoic acids were less reactive and gave moderate yields of desired decarboxylated products.
Comprehensive Overview of Progress in Functionalization of 2‐Pyridone and 2, 4 ‐Dihydroxy Pyridine: Key Constituents of Vital Natural Products
Authors: Yadav Neelam , Sangwan Sarita , Kumar Ravi , Chauhan Sonu , Duhan Anil , Singh Ajay , Arya Rajesh K. 
Published: November 2021

AbstractNitrogen heterocycles have found a key role in biologically active natural products. Pyridones, specifically 2‐pyridone and 2,4‐dihydoxypyridine are an extensive class of compounds with reported occurrence in many natural products. Therefore, the methods for generation of functionalized pyridones are of great interest since their discovery. From traditional coupling to transition metal catalyzed C−H functionalization and transition metal free C−H functionalization, this field has witnessed enormous growth. In the present review, we aim to present a comprehensive overview of pyridone functionalization for young researchers and invite the scientific community to come up with more environment friendly, economic and transition metal free methodologies for corresponding functionalizations.
Studies on the Antioxidant and Antibacterial Activities of In Situ Green Synthesized Graphene‐Gold Nanocomposite
Authors: Kurmarayuni Chandra Mohan , Chandu Basavaiah , Yangalasetty Lakshmi Prasanna , Gali Siva Jyothsna , Khandapu Bala Murali Krishna , Bollikolla Hari Babu 
Published: November 2021

AbstractThe current protocol is focused on the fabrication and applications of gold nanoparticles (Au NPs) distributed on graphene sheets with an emphasis on green synthesis using Kigelia Africana (KA) stem extract. The reducing and stabilizing molecules present in the stem of the KA plant were involved in the transformation of metal ions and graphene oxide in to metal nanoparticles anchored on to reduced graphene oxide sheets. Thus, the obtained graphene‐gold nanocomposite was investigated using sophisticated characterization techniques such as UV‐Visible, Infra‐Red, XRD, Raman, SEM and HRTEM techniques. All these techniques proved the formation of graphene‐gold nanocomposite with the characteristic spectroscopic peaks of graphene and gold. The graphene‐gold nanocomposite exhibited superior antioxidant activity than ascorbic acid standard thus finds medical application as a potential antioxidant agent. Moreover, the nanocomposite also showed good antibacterial activity against five pathogens. These results suggest that the in situ green synthesized graphene‐gold nanocomposite can be used as efficient antibacterial and antioxidants for controlling pathogenic microbes.
Anti‐Stokes Fluorescence and Nonlinear Optical Properties of the Functionalized Phenoxazine‐based Dye: A computational study
Authors: Kariyottu Kuniyil Muhammed Jeneesh , Padmanaban Ramanathan 
Published: November 2021

AbstractTuning of electronic, photophysical and nonlinear optical (NLO) properties of the phenoxazin‐3‐one dye, resazurin (Rz), is here attempted through functionalization by employing the electron‐donating and electron‐withdrawing groups. Density functional theory (DFT) and time‐dependent DFT calculations were performed for the purpose. Examining the absorption‐emission spectra, featuring an intense band (ππ*) followed by a weak band (nπ*), of the functionalized dye derivatives reveal the Stokes shift, and relatively a large shift is found for the cyano‐functionalized Rz molecules. Surprisingly, the 2‐mono‐cyanoresazurin shows the anti‐Stokes fluorescence (ASF) emission induced by the hot‐band absorption, and at the other end, the weak absorption band associated to the charge transfer nπ* transition of the nitro‐functionalized molecules is being quenched. Radiative lifetime analysis infers that the pull‐type functionalized molecules decay slowly whereas the push‐type shows the high emission rate. The structure‐property relations between the molecular parameters were also discussed. Tuning the NLO properties infers that the pull‐type group exhibits significantly high hyperpolarizabilities (for cyano‐) whereas the push‐type exhibits relatively small β‐value (for amino‐) when compared the standard NLO molecule. Here, the tetra‐functionalized‐Rz molecules may act as promising candidates for NLO applications, and also probing their ASF emission further unfolds the bio‐applications.
Green Catalyst‐ and Additive‐Free Three‐Component Deamination Cyclization Synthesis of 3‐Substituted‐4‐ oxo‐2‐quinazolinonyl Sulfides
Authors: Zheng Lvyin , Xie Zhen , Cai Liuhuan , Liu Gongping , Mei Weijie , Zou Xiaoying , Zhuo Xiaoya , Fan Xiaolin , Guo Wei 
Published: November 2021

AbstractAn efficient three‐component deamination annulation of 2‐aminobenzamides, isothiocyanates and alkyl bromides for the synthesis of valuable 3‐substituted‐4‐oxo‐2‐quinazolinonyl sulfides is reported. The reaction proceeds in the absence of any external catalysts and additives. The facile process has the advantages of broad substrate scopes, mild reaction conditions and environmental friendliness, which might provide the synthetic applications for 3‐substituted‐4‐oxo‐2‐quinazolinonyl sulfides as potential anti‐cancer agents in medicinal chemistry.
Total Synthesis of Elmenols A and B and Related Rearranged Angucyclinones
Authors: Ikonnikova Viktoria A. , Solyev Pavel N. , Terekhov Stanislav S. , Alferova Vera A. , Tyurin Anton P. , Korshun Vladimir A. , Baranov Mikhail S. , Mikhaylov Andrey A. 
Published: November 2021

AbstractA synthetic approach towards rearranged angucyclinones related to Elmenols A and B and their synthetic derivatives has been developed. Carbon skeleton is constructed in a straightforward manner by directed o‐lithiation of m‐anisaldehyde dimethyl acetal and its further nucleophilic addition to properly substituted naphthalene carbaldehydes. The latter can be achieved via several alternative synthetic schemes, the most efficient of them are discussed herein.
Quantum imprints of gravitational shockwaves
Authors: Gray Finnian , Kubizňák David , May Taillte , Timmerman Sydney , Tjoa Erickson 
Published: November 2021

Abstract
Gravitational shockwaves are simple exact solutions of Einstein equations representing the fields of ultrarelativistic sources and idealized gravitational waves (shocks). Historically, much work has focused on shockwaves in the context of possible black hole formation in high energy particle collisions, yet they remain at the forefront of research even today. Representing hard modes in the bulk, shocks give rise to the gravitational memory effect at the classical level and implant supertranslation (BMS) hair onto a classical spacetime at the quantum level. The aim of this paper is to further our understanding of the ‘information content’ of such supertranslations. Namely, we show that, contrary to the several claims in the literature, a gravitational shockwave does leave a quantum imprint on the vacuum state of a test quantum field and that this imprint is accessible to local observers carrying Unruh-DeWitt (UDW) detectors in this spacetime.
Extensive allele mining discovers novel genetic diversity in the loci controlling frost tolerance in barley
Authors: Guerra Davide , Morcia Caterina , Badeck Franz , Rizza Fulvia , Delbono Stefano , Francia Enrico , Milc Justyna Anna , Monostori Istvan , Galiba Gabor , Cattivelli Luigi , Tondelli Alessandro 
Published: November 2021

Abstract
Key message
Exome sequencing-based allele mining for frost tolerance suggests HvCBF14 rather than CNV at Fr-H2 locus is the main responsible of frost tolerance in barley.

Abstract
Wild relatives, landraces and old cultivars of barley represent a reservoir of untapped and potentially important genes for crop improvement, and the recent sequencing technologies provide the opportunity to mine the existing genetic diversity and to identify new genes/alleles for the traits of interest. In the present study, we use frost tolerance and vernalization requirement as case studies to demonstrate the power of allele mining carried out on exome sequencing data generated from > 400 barley accessions. New deletions in the first intron of VRN-H1 were identified and linked to a reduced vernalization requirement, while the allelic diversity of HvCBF2a, HvCBF4b and HvCBF14 was investigated by combining the analysis of SNPs and read counts. This approach has proven very effective to identify gene paralogs and copy number variants of HvCBF2 and the HvCBF4b-HvCBF2a segment. A multiple linear regression model which considers allelic variation at these genes suggests a major involvement of HvCBF14, rather than copy number variation of HvCBF4b-HvCBF2a, in controlling frost tolerance in barley. Overall, the present study provides powerful resource and tools to discover novel alleles at relevant genes in barley.
Typical Circulation Patterns and Associated Mechanisms for Persistent Heavy Rainfall Events over Yangtze-Huaihe River Valley during 1981–2020
Authors: Wang Huijie , Sun Jianhua , Fu Shenming , Zhang Yuanchun 
Published: November 2021

AbstractPersistent heavy rainfall events (PHREs) over the Yangtze–Huaihe River Valley (YHRV) during 1981–2020 are classified into three types (type-A, type-B and type-C) according to pattern correlation. The characteristics of the synoptic systems for the PHREs and their possible development mechanisms are investigated. The anomalous cyclonic disturbance over the southern part of the YHRV during type-A events is primarily maintained and intensified by the propagation of Rossby wave energy originating from the northeast Atlantic in the mid–upper troposphere and the northward propagation of Rossby wave packets from the western Pacific in the mid–lower troposphere. The zonal propagation of Rossby wave packets and the northward propagation of Rossby wave packets during type-B events are more coherent than those for type-A events, which induces eastward propagation of stronger anomaly centers of geopotential height from the northeast Atlantic Ocean to the YHRV and a meridional anomaly in geopotential height over the Asian continent. Type-C events have “two ridges and one trough” in the high latitudes of the Eurasian continent, but the anomalous intensity of the western Pacific subtropical high (WPSH) and the trough of the YHRV region are weaker than those for type-A and type-B events. The composite synoptic circulation of four PHREs in 2020 is basically consistent with that of the corresponding PHRE type. The location of the South Asian high (SAH) in three of the PHREs in 2020 moves eastward as in the composite of the three types, but the position of the WPSH of the four PHREs is clearly westward and northward. Two water vapor conveyor belts and two cold air conveyor belts are tracked during the four PHREs in 2020, but the water vapor path from the western Pacific is not seen, which may be caused by the westward extension of the WPSH.