bluuebunny/crossref_metadata_2025_split huggingface dataset:
Mulching and technological interventions avoid land degradation in an intensive oil palm (Elaeis guineensis Jacq.) production system
Authors: Manorama Kamireddy , Behera Sanjib Kumar , Suresh Kancherla , Prasad Musunuru Venkata , Mathur Ravi Kumar , Harinarayana Parasa 
Published: January 2021

AbstractSoil quality characteristics are poorly understood after cultivating oil palm (OP) under irrigated conditions. OP grown under irrigated ecosystem on tropical soils is supplied with huge quantities of water and nutrients without considering changes in soil quality parameters. This may lead to the degradation of fertile lands. To understand the changes that take place in soil properties due to different management practices, data from 132 fixed points have been collected in West Godavari District of Andhra Pradesh in India, from 13‐year‐old plantations and for ca 6 years after imposing mulching and improved resource management interventions. Improvement in soil organic carbon (SOC) content, cation exchange capacity (CEC) available N, P, K, Mg and B contents were recorded due to mulching and improved management. In a monocrop stand of oil palm, mulching alone could enhance SOC content by 52% at 13 years after planting, whereas the corresponding improvement in an intercrop stand (with cocoa) was 77%, above its conventional cultivation SOC without mulching. Mulching in combination with improved management could enhance the SOC content by 40 and 56% respectively after 6 years in sole and intercrop stands respectively, over their corresponding levels at 13 years, in the top 0–30 cm layer. Conventional cultivation of OP recorded a reduction of SOC by 4% during the same time‐span of 6 years. Similar trend was observed in soil available nutrients also. The partial least squares (PLS)‐path model confirmed that sustainable production of oil palm is possible through mulching and improved management.
1.4‐mJ High Energy Terahertz Radiation from Lithium Niobates
Authors: Zhang Baolong , Ma Zhenzhe , Ma Jinglong , Wu Xiaojun , Ouyang Chen , Kong Deyin , Hong Tianshu , Wang Xuan , Yang Peidi , Chen Liming , Li Yutong , Zhang Jie 
Published: January 2021

AbstractFree‐space super‐strong terahertz (THz) electromagnetic fields offer multifaceted capabilities for reaching extreme nonlinear THz optics. However, the lack of powerful solid‐state THz sources with single pulse energy >1 mJ is impeding the proliferation of extreme THz applications. The fundamental challenge lies in hard to achieve high efficiency due to high intensity pumping caused crystal damage, linear absorption, and nonlinear distortion induced short effective interaction length, and so on. Here, through cryogenically cooling the crystals, tailoring the pump laser spectra, chirping the pump pulses, and magnifying the laser energies, 1.4‐mJ THz pulses are successfully realized in lithium niobates under the excitation of 214‐mJ femtosecond laser pulses via tilted pulse front technique. The 800 nm‐to‐THz energy conversion efficiency reaches 0.7%, and a free‐space THz peak electric and magnetic field reaches 6.3 MV cm−1 and 2.1 Tesla. Numerical simulations reproduce the experimental optimization processes. To show the capability of this super‐strong THz source, nonlinear absorption in high conductive silicon induced by strong THz electric field is demonstrated. Such a high‐energy THz source with a relatively low peak frequency is very appropriate not only for electron acceleration toward table‐top X‐ray sources but also for extreme THz science and nonlinear applications.
Single‐Particle Characterization by Elastic Light Scattering
Authors: Romanov Andrey V. , Yurkin Maxim A. 
Published: January 2021

AbstractThe field of light‐scattering characterization of single particles has seen a rapid growth over the last 30 years largely due to the progress in measurement and simulation capabilities. In particular, several methods have been developed to reliably characterize various particles, described by a model with several characteristics, with geometric resolution significantly better than the diffraction limit. However, their development has been largely fragmentary, limited to specific experimental set‐ups. To fill this gap, these lines of development are reviewed within a unified framework. While focusing on characterization algorithms themselves, the experimental aspects related to the isolation and measurement of single particles are also discussed. The existing characterization methods are divided into three classes. The widest class is that of model‐driven methods based on solving parametric inverse light‐scattering problems, using a direct inversion of a low‐dimensional mapping, a nonlinear regression, or neural networks. Other classes include model‐free reconstruction methods and data‐driven classification methods. This review is designed to be extensive in including all relevant literature, but the discussion of semi‐quantitative imaging methods, such as tomography or holography‐based reconstruction, is deliberately omitted. Throughout the review the development of various characterization methods is described, they are critically compared, and promising directions of future research are highlighted.
Lyotropic Morphology Transition of Double Zwitterionic Diblock Copolymer Aqueous Solutions
Authors: Takahashi Masaya , Shimizu Akane , Yusa Shin‐ichi , Higaki Yuji 
Published: January 2021

AbstractPolymer concentration‐dependent aqueous lyotropic morphology transition of a double zwitterionic diblock copolymer composed of a poly(carboxybetaine methacrylate) (PCB) and poly(sulfobetaine methacrylate) (PSB) is unraveled employing small‐angle X‐ray scattering. Salt‐free aqueous solutions of the well‐defined diblock copolymer produce ordered periodic structure and the morphology transforms from hexagonally close‐packed cylinder to lamellar with decreasing the polymer concentration. The morphology transition is induced by the preferential distribution of water molecules into the PCB domains below threshold polymer concentration because of the limited water capacity of the PSB network domains. The volume fraction modulation causes the instability of phase boundary curvature urging the morphology transition. The precise ordered nanostructure control of the highly biocompatible double zwitterionic block copolymers is valid for responsive biocompatible molecular design in biomaterials.
The Influences of Sulfoxide Electron Traps in Transparent Polyimides with Low Retardation, Yellow Index, and CTE
Authors: Jiang Pengfei , Shen Jiulin , Wang Yao , Zhang Jibin , Liu Xiangfu , Tu Guoli 
Published: January 2021

AbstractDue to the development of dynamic flexible organic light‐emitting diode displays, colorless polyimides (CPI) as the supporting or protecting optical films, are facing significant challenges due to the requirements of optical, mechanical, thermal, and chemical properties. Typical CPIs are derived from TFDB (2,2‐bis(trifluoro‐methyl)‐4,4′‐diaminobiphenyl)/6FDA (4,4′‐(hexafluoroisopropylidene)diphthalic anhydride), which still need to be improved in both dimensional stability and optical performance. In this communication, a strong electron acceptor group, the sulfoxide bond, is first introduced into the TFDB block of CPI chains. Based on this introduction, the distribution of the electron cloud in the polymer chain is reconstructed under the strongly pulling electron effect, and the spatial conformation of the polymer chain is also affected by the rigid and twisted sulfoxide group. The influences on CPI's optical properties, especially the refractive index and the retardation, are studied and discussed in detail by experimental results and theoretical calculations. It is shown that the CPI with the sulfoxide group exhibits higher optical transparency, lower yellow index, phase retardation and coefficient of thermal expansion, which is an ideal material for CPI optical films.
Fabrication of High Performance PET/TLCP Fibers through the Synergistic Interfacial Enhancement and Compatibilization of Functional 1D and 2D Carbon Nanomaterials
Authors: Yu Wenguang , Gao Xuefeng , Wang Yuzhou , Wang Xuechen , Zhang Xingxiang 
Published: January 2021

AbstractThe maleic anhydride functionalized graphene oxide (GO‐MA) is fabricated by an efficient and solvent‐free Diels–Alder reaction. Polyethylene terephthalate (PET)/thermotropic liquid crystal polyester (TLCP), PET/TLCP/GO‐MA, PET/TLCP/aminated multi‐walled carbon nanotubes (MWCNTs‐NH2), and PET/TLCP/GO‐MA/MWCNTs‐NH2composite fibers are systematically melt‐spun. The structure and compatibilizing effects of GO‐MA and MWCNTs‐NH2on the mechanical, thermal, and crystallization properties of the composite fibers are indicated. The non‐isothermal crystallization kinetics and X‐ray diffraction (XRD) data show that TLCP and nanofillers can change the crystalline morphology of PET. The mechanical properties of the fibers rise with increasing TLCP content. The tensile strength 929 MPa and modulus 17.5 GPa of the fibers with 7 wt% TLCP and 0.25 wt% nanofillers (0.1 wt% GO‐MA and 0.15 wt% MWCNTs‐NH2) are significantly higher than those with 7 wt% TLCP (tensile strength 622 MPa and modulus 16.1 GPa) and even higher than those with 15% TLCP (tensile strength 836 MPa, and modulus 18.0 GPa). When the GO‐MA and MWCNTs‐NH2co‐exist, the anti‐dripping phenomenon is improved. Therefore, the TLCP, GO, and MWCNTs synergistically strengthens the mechanical properties. This is promising for the industrial fabrication of high‐strength fibers.
A general semianalytical method for computing the propagation characteristics of radially inhomogeneous cylindrical dielectric waveguides
Authors: Weng Qianru , Pan Sichen , Lu Chujie 
Published: January 2021

AbstractA general and simple semianalytical method based on the Galerkin procedure is introduced in this letter for wave propagation problems related to radially inhomogeneous cylindrical dielectric waveguides with arbitrary permittivity profiles. The complicated wave propagation problem in an inhomogeneous waveguide is transformed into a simple problem of solving an equivalent matrix in terms of the Galerkin procedure. Eigenvalue solutions are given for three kinds of representative radially inhomogeneous cylinders to verify the generality of the proposed semianalytical method. The accuracy and the improvement of the convergency are illustrated by comparing the calculated results with those obtained by the analytical method or the matrix numerical method.
Mapping of CSF transport using high spatiotemporal resolution dynamic contrast‐enhanced MRI in mice: Effect of anesthesia
Authors: Stanton Evan Hunter , Persson Niklas Daniel Åke , Gomolka Ryszard Stefan , Lilius Tuomas , Sigurðsson Björn , Lee Hedok , Xavier Anna Lenice Ribeiro , Benveniste Helene , Nedergaard Maiken , Mori Yuki 
Published: January 2021

PurposeDynamic contrast‐enhanced MRI (DCE‐MRI) represents the only available approach for glymphatic cerebrospinal fluid (CSF) flow 3D mapping in the brain of living animals and humans. The purpose of this study was to develop a novel DCE‐MRI protocol for mapping of the glymphatic system transport with improved spatiotemporal resolution, and to validate the new protocol by comparing the transport in mice anesthetized with either isoflurane or ketamine/xylazine.MethodsThe contrast agent, gadobutrol, was administered into the CSF of the cisterna magna and its transport visualized continuously on a 9.4T preclinical scanner using 3D fast‐imaging with a steady‐state free‐precession sequence (3D‐FISP), which has a spatial resolution of 0.001 mm3 and a temporal resolution of 30 s. The MR signals were measured dynamically for 60 min in multiple volumes of interest covering the entire CSF space and brain parenchyma.ResultsThe results confirm earlier findings that glymphatic CSF influx is higher under ketamine/xylazine than with isoflurane anesthesia. This was extended to account for new details about the distinct CSF efflux pathways under the two anesthetic regimens. Dynamic contrast MR shows that CSF clearance occurs mainly along the vagus nerve near the jugular vein under isoflurane and via the olfactory bulb under ketamine/xylazine.ConclusionThe improved spatial and temporal sampling rates afforded by 3D‐FISP shed new light on the pharmacological modulation of CSF efflux paths. The present observations may have the potential to set a new standard for future experimental DCE‐MRI studies of the glymphatic system.
Insights into the effect of bromine‐based organic salts on the efficiency and stability of wide bandgap perovskite
Authors: Cui Xinghua , Wang Pengyang , Shi Biao , Zhao Ying , Zhang Xiaodan 
Published: January 2021

AbstractWide bandgap perovskite solar cells (WB‐PSCs) sustained serious deficit of open‐circuit voltage (VOC) and instability in the development process, which limited the full play of their advantages, especially in tandem solar cells. Surface passivation engineering of alkyl amine halide salts has been used extensively to improve the performance of PSCs. Here, the photovoltaic performance of FA0.83Cs0.17 Pb(I0.8Br0.2)3 WB‐PSCs based on methyl bromide (MABr) and bromide guanidine (GABr) passivation was systematically investigated. It was proved that both MABr and GABr significantly passivate the defects, resulting in lower trap density. Eventually, the efficiency arrives at 18.6% based on MABr‐treated perovskite film, and an improved VOC up to 1.235 V was obtained with a VOC‐deficit of only 415 mV, which is one of the highest value for the PSCs with 1.65 eV bandgap. It is noted that the devices treated with MABr exhibited enhanced moisture stability than that of the reference and GABr treated. X‐Ray Diffraction (XRD) revealed that GABr is likely to cause severer phase transition to δ‐phase nonperovskite. This paper provides an important insight to surface passivation strategies, both performance and stability in devices need to be considered simultaneously.
Simple and efficient continuous data assimilation of evolution equations via algebraic nudging
Authors: Rebholz Leo G. , Zerfas Camille 
Published: January 2021

AbstractWe introduce, analyze, and test an interpolation operator designed for use with continuous data assimilation (DA) of evolution equations that are discretized spatially with the finite element method. The interpolant is constructed as an approximation of the L2 projection operator onto piecewise constant functions on a coarse mesh, but which allows nudging to be done completely at the linear algebraic level, independent of the rest of the discretization, with a diagonal matrix that is simple to construct; it can even completely remove the need for explicit construction of a coarse mesh. We prove the interpolation operator has sufficient stability and accuracy properties, and we apply it to algorithms for both fluid transport DA and incompressible Navier–Stokes DA. For both applications we prove the DA solutions with arbitrary initial conditions converge to the true solution (up to discretization error) exponentially fast in time, and are thus long‐time accurate. Results of several numerical tests are given, which both illustrate the theory and demonstrate its usefulness on practical problems.
Different osteoconductivity of PLLA/PHB composite nanofibers prepared by one‐ and two‐nozzle electrospinning
Authors: Sabouri Elham , Rezaie Zahra , Enderami Seyed Ehsan , Mirahmadi Mahdi , Askari Mohammad 
Published: January 2021

AbstractElectrospinning is a method that has a high potential for use in tissue engineering due to its simplicity, cheapness, versatility, and high applicability for preparing of composite nanofibrous scaffolds. In this study, nanofibrous scaffolds were made of poly‐l‐lactic acid (PLLA) and Polyhydroxybutyrate (PHB) polymers by electrospinning single‐nozzle (combined polymers: C‐PLLA/PHB) and two‐nozzle (separated polymers: S‐PLLA/PHB). Constructed scaffolds were characterized using SEM, in vitro degradation, cell attachment, protein adsorption, and nontoxicity assays. Then, scaffolds osteoconductive capacity was investigated by culturing adipose‐derived stem cells (ADSCs) and by evaluating common osteogenic markers. Obtained results displayed that fibers diameter, scaffold degradation, and biocompatibility of S‐PLLA/PHB nanofibrous scaffold were increased compared to the C‐PLLA/PHB nanofibers. In addition, significantly increased alkaline phosphatase (ALP) activity, calcium content, and osteogenic‐related gene expression were also observed in the ADSCs cultured on S‐PLLA/PHB nanofibrous scaffold compared to the cultured cells on C‐PLLA/PHB nanofibrous scaffold. Overall, this study shows that using two‐nozzle electrospinning to constructing PLLA/PHB nanofibrous scaffold can improve its osteoconductive capacity, and also its combination with ADSCs can be a promising candidate to use in bone tissue engineering.
Morphological, mechanical, and thermal characterization of electrospun three‐dimensional graphite nanoplatelets/polystyrene ultra‐fine fibril composite fabrics
Authors: Fayed A. S. , Abu‐Hasel K. A. , Mahdy Sameh M. , Ali Ashraf A. 
Published: January 2021

AbstractUltra‐fine fibril composites were produced by electrospinning of a polymer solution containing polystyrene (PS)/dimethylformamide (DMF) with different concentrations of three‐dimensional graphite nanoplatelets (3D‐GNPs). Berry's number of PS/DMF polymer solution was extensively studied to produce minimum electrospun PS fiber diameters. Three‐dimensional GNPs of different weight percentages were dispersed in the optimized PS/DMF to produce ultrafine fibril composite fabric. The electrospun average diameters decreased from 1.5 μm for PS fibers to 890 nm for 3D‐GNPs/PS fibril composites, respectively, at 12 and 9.8 Berry's number. High‐resolution transmission electron microscopy samples' micrographs confirm a homogenous dispersion and alignment of 3D‐GNPs in PS fibril composites. Thermal and mechanical characteristics of fabrics were determined using thermogravimetric analysis, thermomechanical Analysis, and dynamic mechanical analysis (DMA). It was found that there was an increase in percentage elongation, tensile strength, thermal stability, and glass‐transition temperature for 3D‐GNPs PS fibril composite fabrics compared to PS fabrics. Diminishing the value of loss tangent, measured by DMA, was used as an approach to predict the maximum amount of 3D‐GNPs weight percent dispersion in electrospun PS/dimethylformamide solution. One of the most important potential applications of the electrospun 3D‐GNPs/PS fibril composite fabrics is in the interiors of vehicles and aerospace industries as it characterizes by its good thermal and mechanical properties as well as its low density.
Noninvasive screening for congenital heart defects using a serum metabolomics approach
Authors: Troisi Jacopo , Cavallo Pierpaolo , Richards Sean , Symes Steven , Colucci Angelo , Sarno Laura , Landolfi Annamaria , Scala Giovanni , Adair David , Ciccone Carla , Maruotti Giuseppe M. , Martinelli Pasquale , Guida Maurizio 
Published: January 2021

AbstractObjectiveHeart anomalies represent nearly one‐third of all congenital anomalies. They are currently diagnosed using ultrasound. However, there is a strong need for a more accurate and less operator‐dependent screening method. Here we report a metabolomics characterization of maternal serum in order to describe a metabolomic fingerprint representative of heart congenital anomalies.MethodsMetabolomic profiles were obtained from serum of 350 mothers (280 controls and 70 cases). Nine classification models were built and optimized. An ensemble model was built based on the results from the individual models.ResultsThe ensemble machine learning model correctly classified all cases and controls. Malonic, 3‐hydroxybutyric and methyl glutaric acid, urea, androstenedione, fructose, tocopherol, leucine, and putrescine were determined as the most relevant metabolites in class separation.ConclusionThe metabolomic signature of second trimester maternal serum from pregnancies affected by a fetal heart anomaly is quantifiably different from that of a normal pregnancy. Maternal serum metabolomics is a promising tool for the accurate and sensitive screening of such congenital defects. Moreover, the revelation of the associated metabolites and their respective biochemical pathways allows a better understanding of the overall pathophysiology of affected pregnancies.
SGLT‐2 inhibitors and the risk of hospitalization for community‐acquired pneumonia: A population‐based cohort study
Authors: Brunetti Vanessa C. , Reynier Pauline , Azoulay Laurent , Yu Oriana Hoi Yun , Ernst Pierre , Platt Robert W. , Filion Kristian B. 
Published: January 2021

AbstractPurposeSodium‐glucose co‐transporter 2 inhibitors (SGLT‐2i) have been associated with an increased risk of genitourinary tract infections. Through similar biological mechanisms, they may also increase the risk of community‐acquired pneumonia. Our objective was to compare the rate of hospitalization for community‐acquired pneumonia (HCAP) with SGLT‐2i compared to dipeptidyl peptidase‐4 inhibitors (DPP‐4i) among patients with type 2 diabetes.MethodsWe used the United Kingdom's Clinical Practice Research Datalink Gold, linked to hospitalization data, to construct a cohort of patients with type 2 diabetes. Using a time‐dependent Cox proportional hazards model, we estimated the adjusted hazard ratio (HR) for HCAP with current use of SGLT‐2i versus DPP‐4i.ResultsAmong 29 896 patients, 705 HCAPs occurred over a mean follow‐up of 1.7 years (SD: 1.2). Incidence rates for SGLT‐2i and DPP‐4i users were 6.2 (95% confidence interval [CI]: 3.7, 10.2) and 17.8 (95% CI: 15.3, 20.7) per 1000 person‐years, respectively. Current use of SGLT‐2i was associated with a decreased risk of HCAP compared to current use of DPP‐4i (adjusted HR: 0.48, 95% CI: 0.28, 0.82). However, a comparison of SGLT‐2i versus glucagon‐like peptide‐1 receptor agonists (GLP‐1 RA) found no difference in risk of HCAP (adjusted HR: 0.94, 95% CI: 0.44, 1.89).ConclusionsSGLT‐2i are associated with a decreased rate of HCAP compared to DPP‐4i, but not when compared to GLP‐1 RA, among patients with type 2 diabetes.
Effect of surface treatment on roughness and bond strength of CAD‐CAM multidirectional glass fiber‐reinforced composite resin used for implant‐supported prostheses
Authors: Kürkçüoğlu Işın , Küçükeşmen Hakkı Cenker , Ozkir Serhat Emre , Yilmaz Burak 
Published: January 2021

AbstractThe study evaluated the effect of different surface treatments on the surface roughness of a new‐generation fiber‐reinforced CAD‐CAM composite resin (FRC) and its bond strength to veneered composite resin. Fifty specimens (10 mm × 10 mm × 1 mm) were prepared from FRC blocks (Trinia; Shofu) and embedded in acrylic resin. The specimens were divided into five groups (n = 10) for different surface treatments: nontreated (control), Al2O3 airborne particle abrasion, silica coating (Cojet), acid etching (H2SO4) and hydrogen peroxide (H2O2) application. Surface roughness (Ra) of the specimens was measured using a profilometer. A veneering composite resin (3 mm in diameter by 4 mm in length) was applied on the specimens. The shear bond strength between the FRC and the veneering resin was measured. A one‐way analysis of variance was used to analyze the data. The differences among the groups were analyzed with Dunn post hoc tests (α = 0.05). Surface treatments increased the surface roughness, and Al2O3 airborne particle abrasion resulted in the highest Ra value followed by H2SO4, Cojet, H2O2 and control group (P < 0.05). The highest shear bond strength was achieved with Al2O3 application (P < 0.05). Cojet and H2O2 applications resulted in higher shear bond strength than the control (P < 0.05). H2SO4 application resulted in lower bond strength than the control (P < 0.05). Surface treatments increased the surface roughness of FRC. Al2O3 and silica coating increased the surface roughness more than the chemical applications. The tested surface treatments can be used to increase the bond strength except for the H2SO4 application. © 2021 Society of Chemical Industry