bluuebunny/crossref_metadata_2025 huggingface dataset:
Localized fluorescent imaging of multiple proteins on individual extracellular vesicles using rolling circle amplification for cancer diagnosis
Authors: Zhang Junli , Shi Jinjin , Zhang Hongling , Zhu Yifan , Liu Wei , Zhang Kaixiang , Zhang Zhenzhong
Published: December 2020

Extracellular vesicles (EV) have attracted increasing attention as tumour biomarkers due to their unique biological property. However, conventional methods for EV analysis are mainly based on bulk measurements, which masks the EV‐to‐EV heterogeneity in tumour diagnosis and classification. Herein, a localized fluorescent imaging method (termed Digital Profiling of Proteins on Individual EV, DPPIE) was developed for analysis of multiple proteins on individual EV. In this assay, an anti‐CD9 antibody engineered biochip was used to capture EV from clinical plasma sample. Then the captured EV was specifically recognized by multiple DNA aptamers (CD63/EpCAM/MUC1), followed by rolling circle amplification to generate localized fluorescent signals. By‐analyzing the heterogeneity of individual EV, we found that the high‐dimensional data collected from each individual EV would provide more precise information than bulk measurement (ELISA) and the percent of CD63/EpCAM/MUC1‐triple‐positive EV in breast cancer patients was significantly higher than that of healthy donors, and this method can achieve an overall accuracy of 91%. Moreover, using DPPIE, we are able to distinguish the EV between lung adenocarcinoma and lung squamous carcinoma patients. This individual EV heterogeneity analysis strategy provides a new way for digging more information on EV to achieve multi‐cancer diagnosis and classification.
Extracellular vesicles derived from macrophages display glycyl‐tRNA synthetase 1 and exhibit anti‐cancer activity
Authors: Goughnour Peter C. , Park Min Chul , Kim Sang Bum , Jun Sangmi , Yang Won Suk , Chae Sehyun , Cho Seongmin , Song Chihong , Lee Ji‐Hyun , Hyun Jae Kyung , Kim Byung Gyu , Hwang Daehee , Jung Hyun Suk , Gho Yong Song , Kim Sunghoon
Published: December 2020

Glycyl‐tRNA synthetase 1 (GARS1), a cytosolic enzyme secreted from macrophages, promotes apoptosis in cancer cells. However, the mechanism underlying GARS1 secretion has not been elucidated. Here, we report that GARS1 is secreted through unique extracellular vesicles (EVs) with a hydrodynamic diameter of 20–58 nm (mean diameter: 36.9 nm) and a buoyant density of 1.13–1.17 g/ml. GARS1 was anchored to the surface of these EVs through palmitoylated C390 residue. Proteomic analysis identified 164 proteins that were uniquely enriched in the GARS1‐containing EVs (GARS1‐EVs). Among the identified factors, insulin‐like growth factor II receptor, and vimentin also contributed to the anti‐cancer activity of GARS1‐EVs. This study identified the unique secretory vesicles containing GARS1 and various intracellular factors that are involved in the immunological defence response against tumorigenesis.
Exponential time differencing implementation of the stretched coordinate perfectly matched layer
Authors: Huang Shou Jiang , Wang P. X.
Published: December 2020

The exponential time differencing (ETD) formulation for the stretched coordinate perfectly matched layer (PML) is proposed through the Taylor expansion. This general D and B formulation can be used to truncate arbitrary media in the FDTD simulations. The numerical experiments validate the effectiveness of the ETD schemes. The computational efficiency of the ETD algorithm is identical to that of simple auxiliary differential equation method. The ETD is superior to any other implementation of the stretched coordinate and uniaxial PMLs. The optimum value of the effective relative permittivity for the inhomogeneous media can reduce the peak relative reflection error of the PML by about 15 dB relative to the average value. The performance of the PML is improved remarkably.
Sensorimotor dysfunction in a mild mouse model of cortical contusion injury without significant neuronal loss is associated with increases in inflammatory proteins with innate but not adaptive immune functions
Authors: Nieves Michael D. , Furmanski Orion , Doughty Martin L.
Published: December 2020

Traumatic brain injury is a leading cause of mortality and morbidity in the United States. Acute trauma to the brain triggers chronic secondary injury mechanisms that contribute to long‐term neurological impairment. We have developed a single, unilateral contusion injury model of sensorimotor dysfunction in adult mice. By targeting a topographically defined neurological circuit with a mild impact, we are able to track sustained behavioral deficits in sensorimotor function in the absence of tissue cavitation or neuronal loss in the contused cortex of these mice. Stereological histopathology and multiplex enzyme‐linked immunosorbent assay proteomic screening confirm contusion resulted in chronic gliosis and the robust expression of innate immune cytokines and monocyte attractant chemokines IL‐1β, IL‐5, IL‐6, TNFα, CXCL1, CXCL2, CXCL10, CCL2, and CCL3 in the contused cortex. In contrast, the expression of neuroinflammatory proteins with adaptive immune functions was not significantly modulated by injury. Our data support widespread activation of innate but not adaptive immune responses, confirming an association between sensorimotor dysfunction with innate immune activation in the absence of tissue or neuronal loss in our mice.
An Intelligent Reminder System Reduces Deficiencies and Errors in Ultrasound Reports
Authors: Zhang Yan‐Fen , Li Jian , Jin Lin‐Yuan , Li Fen‐Sui
Published: December 2020

Objectives

We designed a computer‐based, integrated intelligent reminder system to reduce the deficiencies and errors in ultrasound (US) reports. In this study, we assessed the performance of this system and evaluated its impact on the quality of US reporting.

Methods

Ultrasound reporting deficiencies or errors were divided into 2 categories: missing items (including outpatient or inpatient number and clinical diagnosis) and content errors (including measurement data, sex‐related, and laterality errors). The intelligent reminder system was designed in Visual Basic for Applications (Microsoft Corporation, Redmond, WA) and integrated with the US system. It automatically detects reporting errors before printing of the report and provides real‐time prompts for correction of the errors. We compared the US reporting deficiencies and errors during the 20 months before and after implementation of the system.

Results

Before implementation of the system, deficiencies/errors were detected in 2.26% (8841 of 391,230) of US reports compared with 0.12% (530 of 444,215) of reports after implementation of the system (P < .0001). After adoption of the system, the reported item deficiencies were improved more than the content deficiencies, with the most notable improvement in clinical diagnosis. Sex‐related errors were reduced from 7 cases to nil after use of the intelligent reminder system. No laterality errors were found before and after the implementation of the system.

Conclusions

The intelligent reminder system within the US system significantly reduced deficiencies and errors, improving the quality of the report.
Automated plankton classification from holographic imagery with deep convolutional neural networks
Authors: Guo Buyu , Nyman Lisa , Nayak Aditya R. , Milmore David , McFarland Malcolm , Twardowski Michael S. , Sullivan James M. , Yu Jia , Hong Jiarong
Published: December 2020

In situ digital inline holography is a technique which can be used to acquire high‐resolution imagery of plankton and examine their spatial and temporal distributions within the water column in a nonintrusive manner. However, for effective expert identification of an organism from digital holographic imagery, it is necessary to apply a computationally expensive numerical reconstruction algorithm. This lengthy process inhibits real‐time monitoring of plankton distributions. Deep learning methods, such as convolutional neural networks, applied to interference patterns of different organisms from minimally processed holograms can eliminate the need for reconstruction and accomplish real‐time computation. In this article, we integrate deep learning methods with digital inline holography to create a rapid and accurate plankton classification network for 10 classes of organisms that are commonly seen in our data sets. We describe the procedure from preprocessing to classification. Our network achieves 93.8% accuracy when applied to a manually classified testing data set. Upon further application of a probability filter to eliminate false classification, the average precision and recall are 96.8% and 95.0%, respectively. Furthermore, the network was applied to 7500 in situ holograms collected at East Sound in Washington during a vertical profile to characterize depth distribution of the local diatoms. The results are in agreement with simultaneously recorded independent chlorophyll concentration depth profiles. This lightweight network exemplifies its capability for real‐time, high‐accuracy plankton classification and it has the potential to be deployed on imaging instruments for long‐term in situ plankton monitoring.
Status and Outlook of Metal–Inorganic Semiconductor–Metal Photodetectors
Authors: Shi Linlin , Chen Keqiang , Zhai Aiping , Li Guohui , Fan Mingming , Hao Yuying , Zhu Furong , Zhang Han , Cui Yanxia
Published: December 2020

Metal–inorganic semiconductor–metal photodetectors (MSM‐PDs) have received great attention in many areas, such as optical fiber communication, sensing, missile guidance, etc., due to their inherent merits of high speed, high sensitivity, and easy integration. This review focuses on MSM‐PDs with the semiconductor layer made of inorganic materials including traditional semiconductors (such as GaAs and Si), the third‐generation wide bandgap semiconductors (such as GaN, ZnO, and SiC), as well as several emerging semiconductors (such as perovskites and 2D materials). First, the basic structures of MSM‐PDs, including the planar and vertical configurations, are presented. Then, their working principles of MSM‐PDs are discussed. Subsequently, the research progresses on MSM‐PDs consisting of different photosensitive semiconductor materials are described in detail. Additionally, the efforts to optimize MSM‐PDs from the aspects of dark current, response speed, responsivity, spectral adjustment, etc., are also introduced. Finally, the review is concluded with the perspectives of MSM‐PDs from the authors’ vision.
Progress in the Free and Controlled Radical Homo‐ and Co‐Polymerization of Itaconic Acid Derivatives: Toward Functional Polymers with Controlled Molar Mass Distribution and Architecture
Authors: Sollka Lea , Lienkamp Karen
Published: December 2020

Polymeric derivatives of itaconic acid are becoming increasingly more interesting for research and industry because itaconic acid is accessible from renewable resources. In spite of the structural similarity of poly(itaconic acid derivatives) to poly(methacrylates), they are much less reactive, homopolymerize only sluggishly by free radical polymerization (FRP), and are often obtained with low molar masses and conversions. This has so far limited their use. The reasons for the low reactivity of itaconic acid derivatives (including itaconimides, diitaconates, and diitaconamides) are combined steric and electronic effects, as demonstrated by the body of literature on the FRP homopolymerization kinetics of these monomers which is summarized herein. These problems can be solved to a large extent by using controlled radical polymerization (CRP) techniques, notably atom transfer radical polymerization (ATRP) and reversible addition and fragmentation chain transfer radical polymerization (RAFT). By optimizing the reaction conditions for the ATRP and RAFT of itaconic acid derivatives, in particular the reaction temperature, linear relations between molar mass and conversion are obtained in many cases, and homopolymers with high molar masses and reasonably narrow polydispersity indices become accessible. This review presents the state‐of‐the‐art FRP and CRP of itaconic acid derivatives, and highlights functional polymers obtained by these methods.
Facile Synthesis of Sequence‐Defined Oligo(Dimethylsiloxane‐co‐Diphenylsiloxane)s
Authors: Kawatsu Takahiro , Choi Jun‐Chul , Sato Kazuhiko , Matsumoto Kazuhiro
Published: December 2020

1,1,3,3,5,5,7,7‐Octamethyltetrasiloxane (HMD2MH), which is reported to release Me2SiH2 via a B(C6F5)3‐catalyzed redistribution, acts as a good Me2SiH2 precursor in the B(C6F5)3‐catalyzed dehydrocarbonative condensation of alkoxysilanes. A series of oligo(dimethylsiloxane‐co‐diphenylsiloxane)s that are uniformly sized and sequence‐defined at the atomic level are synthesized by a one‐pot controlled iteration of a B(C6F5)3‐catalyzed dehydrocarbonative condensation of alkoxysilanes with HMD2MH or Ph2SiH2 and a B(C6F5)3‐catalyzed hydrosilylation of carbonyl compounds, followed by the subsequent B(C6F5)3‐catalyzed dehydrogenative condensation of silanols.
Luminescent and Robust Perovskite–Silicone Elastomers Prepared by Light Induced Thiol–Ene Reaction
Authors: Guo Mengdong , Huang Yue , Cao Jinfeng , Xu Yunfan , Lu Shilong , Feng Shengyu
Published: December 2020

The preparation of a series of luminescent perovskite–silicone elastomer (PSE) composites by embedding inorganic lead halide perovskite nanocrystals (CsPbBr3 NCs) into networks constructed by trimethylolpropane tris(2‐mercaptoacetate) and sulfone‐containing silicone copolymers with vinyl side groups (PSMVS) is reported herein. The networks are obtained by an environmentally friendly thiol–ene cross‐linking reaction under 30 W household LED light. The conducted analysis shows that the prepared PSEs display strong green fluorescence due to encapsulation of CsPbBr3 NCs, which constitute a luminescent center in sulfone‐containing silicone networks. Using PSMVS as basic polymers instead of commercial polysiloxanes endows PSEs with enhanced mechanical strength and excellent luminescent stability at high temperatures. The PSEs show robust tensile stress and >650% elongation. Additionally, the construction of colorful ultraviolet light‐emitting diodes (UV‐LEDs) by an in situ cross‐linking process is described.
A comparative study of convolutional neural network models for wind field downscaling
Authors: Höhlein Kevin , Kern Michael , Hewson Timothy , Westermann Rüdiger
Published: December 2020

We analyze the applicability of convolutional neural network (CNN) architectures for downscaling of short‐range forecasts of near‐surface winds on extended spatial domains. Short‐range wind forecasts (at the 100 m level) from European Centre for Medium Range Weather Forecasts ERA5 reanalysis initial conditions at 31 km horizontal resolution are downscaled to mimic high resolution (HRES) (deterministic) short‐range forecasts at 9 km resolution. We evaluate the downscaling quality of four exemplary CNN architectures and compare these against a multilinear regression model. We conduct a qualitative and quantitative comparison of model predictions and examine whether the predictive skill of CNNs can be enhanced by incorporating additional atmospheric variables, such as geopotential height and forecast surface roughness, or static high‐resolution fields, like land–sea mask and topography. We further propose DeepRU, a novel U‐Net‐based CNN architecture, which is able to infer situation‐dependent wind structures that cannot be reconstructed by other models. Inferring a target 9 km resolution wind field from the low‐resolution input fields over the Alpine area takes less than 10 ms on our graphics processing unit target architecture, which compares favorably to an overhead in simulation time of minutes or hours between low‐ and high‐resolution forecast simulations.
A narrow band and high selectivity half‐mode substrate integrated waveguide bandpass filter with interdigital slots
Authors: Pelluri Sambaiah , M.V. Kartikeyan
Published: December 2020

A novel in‐line half‐mode substrate integrated waveguide (HMSIW) bandpass filter with interdigital slots has been proposed in this letter. Here, the interdigital slot shows attenuation resonance characteristics and generates a finite frequency transmission zero (TZ). The proposed filter generates two TZs without additional coupling or extra space and exhibits wide stopband characteristics. To validate this method, the in‐line two‐pole quasi‐elliptic bandpass filter is synthesized and fabricated on RT/Duroid 5880 substrate using printed circuit board technology. The experimental results show that center frequency, 3‐dB fractional bandwidth, insertion loss, and return loss are 3.6 GHz, 6.0%, 1.9 and 18 dB, respectively, and are very much similar to the simulated S‐parameters.
Free‐water DTI estimates from single b‐value data might seem plausible but must be interpreted with care
Authors: Golub Marc , Neto Henriques Rafael , Gouveia Nunes Rita
Published: December 2020

Purpose

Free‐water elimination DTI (FWE‐DTI) has been used widely to distinguish increases of free‐water partial‐volume effects from tissue’s diffusion in healthy aging and degenerative diseases. Because the FWE‐DTI fitting is only well‐posed for multishell acquisitions, a regularized gradient descent (RGD) method was proposed to enable application to single‐shell data, more common in the clinic. However, the validity of the RGD method has been poorly assessed. This study aims to quantify the specificity of FWE‐DTI procedures on single‐shell and multishell data.

Methods

Different FWE‐DTI fitting procedures were tested on an open‐source in vivo diffusion data set and single‐shell and multishell synthetic signals, including the RGD and standard nonlinear least‐squares methods. Single‐voxel simulations were carried out to compare initialization approaches. A multivoxel phantom simulation was performed to evaluate the effect of spatial regularization when comparing between methods. To test the algorithms’ specificity, phantoms with two different types of lesions were simulated: with altered mean diffusivity or with modified free water.

Results

Plausible parameter maps were obtained with RGD from single‐shell in vivo data. The plausibility of these maps was shown to be determined by the initialization. Tests with simulated lesions inserted into the in vivo data revealed that the RGD approach cannot distinguish free water from tissue mean‐diffusivity alterations, contrarily to the nonlinear least‐squares algorithm.

Conclusion

The RGD FWE‐DTI method has limited specificity; thus, its results from single‐shell data should be carefully interpreted. When possible, multishell acquisitions and the nonlinear least‐squares approach should be preferred instead.
A fast navigator (fastNAV) for prospective respiratory motion correction in first‐pass myocardial perfusion imaging
Authors: Mooiweer Ronald , Neji Radhouene , McElroy Sarah , Nazir Muhummad Sohaib , Razavi Reza , Chiribiri Amedeo , Roujol Sébastien
Published: December 2020

Purpose

To develop and evaluate a fast respiratory navigator (fastNAV) for cardiac MR perfusion imaging with subject‐specific prospective slice tracking.

Methods

A fastNAV was developed for dynamic contrast‐enhanced cardiac MR perfusion imaging by combining spatially nonselective saturation with slice‐selective tip‐up and slice‐selective excitation pulses. The excitation slice was angulated from the tip‐up slice in the transverse plane to overlap only in the right hemidiaphragm for suppression of signal outside the right hemidiaphragm. A calibration scan was developed to enable the estimation of subject‐specific tracking factors. Perfusion imaging using subject‐specific fastNAV‐based slice tracking was then compared to a conventional sequence (ie, without slice tracking) in 10 patients under free‐breathing conditions. Respiratory motion in perfusion images was quantitatively assessed by measuring the average overlap of the left ventricle across images (avDice, 0:no overlap/1:perfect overlap) and the average displacement of the center of mass of the left ventricle (avCoM). Image quality was subjectively assessed using a 4‐point scoring system (1: poor, 4: excellent).

Results

The fastNAV calibration was successfully performed in all subjects (average tracking factor of 0.46 ± 0.13, R = 0.94 ± 0.03). Prospective motion correction using fastNAV led to higher avDice (0.94 ± 0.02 vs. 0.90 ± 0.03, P < .001) and reduced avCoM (4.03 ± 0.84 vs. 5.22 ± 1.22, P < .001). There were no statistically significant differences between the 2 sequences in terms of image quality (both sequences: median = 3 and interquartile range = 3‐4, P = 1).

Conclusion

fastNAV enables fast and robust right hemidiaphragm motion tracking in a perfusion sequence. In combination with subject‐specific slice tracking, fastNAV reduces the effect of respiratory motion during free‐breathing cardiac MR perfusion imaging.
Cardiac real‐time MRI using a pre‐emphasized spiral acquisition based on the gradient system transfer function
Authors: Eirich Philipp , Wech Tobias , Heidenreich Julius F. , Stich Manuel , Petri Nils , Nordbeck Peter , Bley Thorsten A. , Köstler Herbert
Published: December 2020

Purpose

Segmented Cartesian acquisition in breath hold represents the current gold standard for cardiac functional MRI. However, it is also associated with long imaging times and severe restrictions in arrhythmic or dyspneic patients. Therefore, we introduce a real‐time imaging technique based on a spoiled gradient‐echo sequence with undersampled spiral k‐space trajectories corrected by a gradient pre‐emphasis.

Methods

A fully automatic gradient waveform pre‐emphasis based on the gradient system transfer function was implemented to compensate for gradient inaccuracies, to optimize fast double‐oblique spiral MRI. The framework was tested in a phantom study and subsequently transferred to compressed sensing–accelerated cardiac functional MRI in real time. Spiral acquisitions during breath hold and free breathing were compared with this reference method for healthy subjects (N = 7) as well as patients (N = 2) diagnosed with heart failure and arrhythmia. Left‐ventricular volumes and ejection fractions were determined and analyzed using a Wilcoxon signed‐rank test.

Results

The pre‐emphasis successfully reduced typical artifacts caused by k‐space misregistrations. Dynamic cardiac imaging was possible in real time (temporal resolution < 50 ms) with high spatial resolution (1.34 × 1.34 mm2), resulting in a total scan time of less than 50 seconds for whole heart coverage. Comparable image quality, as well as similar left‐ventricular volumes and ejection fractions, were observed for the accelerated and the reference method.

Conclusion

The proposed technique enables high‐resolution real‐time cardiac MRI with no need for breath holds and electrocardiogram gating, shortening the duration of an entire functional cardiac exam to less than 1 minute.
Using MRI to quantify skeletal muscle pathology in Duchenne muscular dystrophy: A systematic mapping review
Authors: Alic Lejla , Griffin John F. , Eresen Aydin , Kornegay Joe N. , Ji Jim X.
Published: December 2020

There is a great demand for accurate non‐invasive measures to better define the natural history of disease progression or treatment outcome in Duchenne muscular dystrophy (DMD) and to facilitate the inclusion of a large range of participants in DMD clinical trials. This review aims to investigate which MRI sequences and analysis methods have been used and to identify future needs. Medline, Embase, Scopus, Web of Science, Inspec, and Compendex databases were searched up to 2 November 2019, using keywords “magnetic resonance imaging” and “Duchenne muscular dystrophy.” The review showed the trend of using T1w and T2w MRI images for semi‐qualitative inspection of structural alterations of DMD muscle using a diversity of grading scales, with increasing use of T2map, Dixon, and MR spectroscopy (MRS). High‐field (>3T) MRI dominated the studies with animal models. The quantitative MRI techniques have allowed a more precise estimation of local or generalized disease severity. Longitudinal studies assessing the effect of an intervention have also become more prominent, in both clinical and animal model subjects. Quality assessment of the included longitudinal studies was performed using the Newcastle‐Ottawa Quality Assessment Scale adapted to comprise bias in selection, comparability, exposure, and outcome. Additional large clinical trials are needed to consolidate research using MRI as a biomarker in DMD and to validate findings against established gold standards. This future work should use a multiparametric and quantitative MRI acquisition protocol, assess the repeatability of measurements, and correlate findings to histologic parameters.
The supplement role of iron oxide and zirconium oxide nanoparticles as an advanced composite compound for enhancing the efficiency of thin‐film nanocomposite membranes
Authors: Karimi Rezvan , Homayoonfal Maryam
Published: December 2020

In this research, to enhance the efficiency of polyacrylonitrile, iron oxide (Fe3O4) nanoparticles were added to membrane matrix and M(0,1) (PA/FePAN) membrane was fabricated. To boost the effectiveness, the iron oxide/zirconium oxide composite nanoparticles (Zr©Fe) were added to the superficial polyamide layer to synthesize M(1,0) (Zr©FePA/PAN) membrane. In order to investigate the supplement role of Fe3O4 and Zr©Fe nanoparticles, both nanoparticles were added to PAN substrate and PA superficial layer, respectively, to fabricate M(1,1) (Zr©FePA/FePAN) membrane. The performance of nanocomposite membranes was compared with that of M(0,0) (PA/PAN) raw membrane. The results indicated that the contact angle of M(0,0), M(0,1), M(1,0), and M(1,1) membranes was 38, 32, 28, and 21, respectively. Presence of nanoparticles enhanced the membrane porosity, such that the porosity of M(0,0), M(1,0), M(0,1), and M(1,1) membranes was 24%, 27%, 30%, and 33%, respectively. MWCO for M(0,0), M(0,1), M(1,0), and M(1,1) membranes was 610, 595, 380, and 330 Dalton, respectively. Presence of nanoparticles reduced fouling from 22% for M(0,0) membrane to zero for M(1,1) membrane. Presence of Fe3O4 nanoparticles and Zr©Fe composite nanoparticles concurrently in both membrane layers eventually caused M(1,1) to have around 23% greater flux and 68% higher efficiency for cephalexin rejection compared to M(0,0).
Review on the performances, foaming and injection molding simulation of natural fiber composites
Authors: Zhan Jianghu , Li Jiao , Wang Guilong , Guan Yanjin , Zhao Guoqun , Lin Jun , Naceur Hakim , Coutellier Daniel
Published: December 2020

Recently, natural fiber becomes an alternative to the synthetic fiber for the composites used in aerospace, automotive, sports, packaging and so on, due to its inherent characteristics like biodegradablity, renewablity, high‐specific strength and specific modulus. However, there are still many challenges in the fabrication of the natural fiber composites, including the poor compatibility between the nonpolar matrix and the polar natural fiber, relatively high‐moisture absorption and low‐thermal resistance of natural fibers, etc. Moreover, when manufacturing this type composite, the processing conditions, fiber loading and inherent properties of fiber not only affect the mechanical properties, but also cause products defects, such as warpage, volume shrinkage and weld lines, which needs a rapid numerical design for the mold and manufacturing parameters. Therefore, the properties of natural fiber composites have been widely investigated to satisfy the increasing demand in different applications. This paper intends to review the mechanical properties, flammability, durability, foaming behaviors and numerical simulation of injection molding process of natural fiber composites.
Differentiation of the binding of two ligands to a tetrameric protein with a single symmetric active site by 19F NMR
Authors: Fuente‐Gómez Gabriel J. , Kellum Creighton L. , Miranda Alexis C. , Duff Michael R. , Howell Elizabeth E.
Published: December 2020

R67 dihydrofolate reductase (R67 DHFR) is a plasmid‐encoded enzyme that confers resistance to the antibacterial drug trimethoprim. R67 DHFR is a tetramer with a single active site that is unusual as both cofactor and substrate are recognized by symmetry‐related residues. Such promiscuity has limited our previous efforts to differentiate ligand binding by NMR. To address this problem, we incorporated fluorine at positions 4, 5, 6, or 7 of the indole rings of tryptophans 38 and 45 and characterized the spectra to determine which probe was optimal for studying ligand binding. Two resonances were observed for all apo proteins. Unexpectedly, the W45 resonance appeared broad, and truncation of the disordered N‐termini resulted in the appearance of one sharp W45 resonance. These results are consistent with interaction of the N‐terminus with W45. Binding of the cofactor broadened W38 for all fluorine probes, whereas substrate, dihydrofolate, binding resulted in the appearance of three new resonances for 4‐ and 5‐fluoroindole labeled protein and severe line broadening for 6‐ and 7‐fluoroindole R67 DHFR. W45 became slightly broader upon ligand binding. With only two peaks in the 19F NMR spectra, our data were able to differentiate cofactor and substrate binding to the single, symmetric active site of R67 DHFR and yield binding affinities.
RNAi‐based gene silencing in Phenacoccus solenopsis and its validation by in planta expression of a double‐stranded RNA
Authors: Arya Surjeet Kumar , Singh Sanchita , Upadhyay Santosh Kumar , Tiwari Vipin , Saxena Gauri , Verma Praveen C
Published: December 2020

BACKGROUND

Cotton is a cash crop majorly affected by many hemipteran pests, among them the cotton mealybug, Phenacoccus solenopsis. Cotton mealybug attack has a devastating effect on cotton production and causes huge yield losses.

RESULTS

In this study, 25 potential RNA interference (RNAi) target genes were selected from the iBeetle database and a transcriptome data set for P. solenopsis. To assess the effectiveness of the selected target genes, three methods were utilized to deliver double‐stranded (ds)RNA (ingestion, artificial diet bioassay and transient gene silencing). dsRNA molecules at different concentrations were fed to insects and insect mortality was recorded for each target gene. Based on the mortality data, three genes, Krüppel homologue‐1, ADP‐ATP/Translocase and IDGF‐1, were selected for further gene expression studies using a reduced concentration of dsRNA (5 μg/ml). Of the three genes, Krüppel homologue‐1 showed significantly downregulated expression (by 70.81% and 84.33%) at two different time points (8 and 14 days). An RNAi silencing construct was designed for Krüppel homologue‐1 under control of the double enhancer CamV35S promoter in the plant binary vector. Significant downregulation of gene expression, by 66.69% and 81.80%, was found for Krüppel homologue‐1 using transient gene silencing at the same time intervals.

CONCLUSION

This work provides the first evidence for targeting the Krüppel homologue‐1 gene in a hemipteran pest, P. solenopsis, using RNAi technology through oral delivery and in planta‐based transient gene silencing methods. © 2020 Society of Chemical Industry
Long‐term effect of fumigation and a sorghum cover crop on broadleaf and grass weeds in plastic‐mulched tomato
Authors: Yu Jialin , Sharpe Shaun M , Boyd Nathan S
Published: December 2020

BACKGROUND

Broadleaf and grass weeds can adversely affect growth and productivity of plastic‐mulched tomato (Solanum lycopersicum L.). Two, four‐year research trials were conducted in Florida to evaluate the effect of repeated fumigation and chemical fallow versus a sorghum [Sorghum bicolor S. bicolor var. sudanense (Piper) Stapf.] cover crop on broadleaf and grass weeds in tomato plasticulture.

RESULTS

1,3‐Dichloropropene (1,3‐D) + chloropicrin (Pic), dimethyl disulfide (DMDS) + Pic, and DMDS + metam potassium effectively controlled broadleaf weeds in‐crop and reduced densities by 79–98% compared to the non‐fumigated control but provided inconsistent control of grass weeds. DMDS + metam potassium was generally the most effective fumigant. During the fallow period, a sorghum cover crop effectively reduced broadleaf weed density than the chemical fallow, while chemical fallow effectively reduced grass weed density than the cover crop. The fallow program did not affect in‐crop densities of broadleaf and grass weeds. In some measurements, the evaluated fumigants resulted in taller tomato plants and higher yield compared to the non‐fumigated control.

CONCLUSION

We conclude that the evaluated soil fumigants effectively control broadleaf and grass weeds. Planting a sorghum cover crop effectively suppresses broadleaf weeds but not grasses during the fallow period. However, this suppression does not result in reduced weed density in‐crop despite the fact that similar weed species were observed in both time periods. © 2020 Society of Chemical Industry
Factors affecting deer pressure on forest regeneration: The roles of forest roads, visibility and forage availability
Authors: Borowski Zbigniew , Bartoń Kamil , Gil Wojciech , Wójcicki Adam , Pawlak Bogdan
Published: December 2020

BACKGROUND

Deer pressure on forest regeneration constitutes a serious problem in commercial forests in the northern hemisphere due to the increase in deer populations. However, other drivers, such as climate, landscape structure and the level of human activity, have a strong influence on deer pressure. The direct, density‐related impacts of ungulates on forest regeneration have been well studied, but there is limited empirical evidence related to the indirect factors mentioned above. We conducted a field experiment in three forest divisions in Poland to evaluate the role of a common element of human infrastructure, i.e. small, unpaved forestry roads. Additionally, we assessed the modifying effect of visibility driven by vegetation cover and forage availability.

RESULTS

The proximity of unpaved roads affected deer habitat use and foraging behaviour, and limited browsing pressure on regenerating forests. Low visibility and higher winter forage availability increased the probability of tree browsing. We observed different responses to roads in two deer species: red deer avoided roads, while roe deer browsed in the vicinity of roads.

CONCLUSIONS

A typical forest network of unpaved roads creates a landscape of fear for red and roe deer, and limits browsing pressure on regenerating forests due to the changes in deer habitat use, activity patterns and foraging behaviour. Knowledge of the factors influencing browsing pressure can help to spatially optimise the application of protective measures for tree seedlings.
Variational Quantum Generators: Generative Adversarial Quantum Machine Learning for Continuous Distributions
Authors: Romero Jonathan , Aspuru‐Guzik Alán
Published: December 2020

A hybrid quantum–classical approach to model continuous classical probability distributions using a variational quantum circuit is proposed. The architecture of this quantum generator consists of a quantum circuit that encodes a classical random variable into a quantum state and a parameterized quantum circuit trained to mimic the target distribution. The model allows for easy interfacing with a classical function, such as a neural network, and is trained using an adversarial learning approach. It is shown that the quantum generator is able to learn using either a classical neural network or a variational quantum circuit as the discriminator model. This implementation takes advantage of automatic differentiation tools to perform the optimization of the variational circuits employed. The framework presented here for the design and implementation of the variational quantum generators can serve as a blueprint for designing hybrid quantum–classical models for other machine learning tasks.
Enhanced Spin Hall Effect in S‐Implanted Pt
Authors: Shashank Utkarsh , Medwal Rohit , Shibata Taiga , Nongjai Razia , Vas Joseph Vimal , Duchamp Martial , Asokan Kandasami , Rawat Rajdeep Singh , Asada Hironori , Gupta Surbhi , Fukuma Yasuhiro
Published: December 2020

High efficiency of charge–spin interconversion in spin Hall materials is a prime necessity to apprehend intriguing functionalities of spin–orbit torque for magnetization switching, auto‐oscillations, and domain wall motion in energy‐efficient and high‐speed spintronic devices. To this end, innovations in fabricating advanced materials that possess not only large charge–spin conversion efficiency but also viable electrical and spin Hall conductivity are of importance. Here, a new spin Hall material designed by implanting low energy 12 keV sulfur ions in heavy metal Pt, named as Pt(S), is reported that demonstrates eight times higher conversion efficiency as compared to pristine Pt. The figure of merit, spin Hall angle (θSH), up to of 0.502 together with considerable electrical conductivity of 1.65 × 106 Ω–1 m–1 is achieved. The spin Hall conductivity increases with increasing , as , implying an intrinsic mechanism in a dirty metal conduction regime. A comparatively large of 8.32 × 105 () Ω–1 m–1 among the reported heavy‐metals‐based alloys can be useful for developing next‐generation spintronic devices using spin–orbit torque.
The Origin of Quantum Effects in Low‐Dimensional Thermoelectric Materials
Authors: Hung Nguyen T. , Saito Riichiro
Published: December 2020

Thermoelectric material, which directly converts waste heat to electricity, provides an ecofriendly power generator to reuse heat energy sources. New attempts have started for thermoelectricity of low‐dimensional materials since 1993 when the theory of confinement effect was presented by Hicks and Dresselhaus. Experimental works have been inspired by the theory of confinement to the use of low‐dimensional materials for improving thermoelectric efficiency for more than two decades. In this report, it is considered how recent theories and experiments have made progress on the quantum confinement effects. In particular, the reason is explained why the thermal de Broglie wavelength becomes a key parameter to enhance the power factor.
Characterisation of new reference materials IAEA‐610, IAEA‐611 and IAEA‐612 aimed at the VPDB δ13C scale realisation with small uncertainty
Authors: Assonov Sergey , Fajgelj Ales , Hélie Jean‐François , Allison Colin , Gröning Manfred
Published: December 2020

Rationale

LSVEC, the second anchor Reference Material (RM) for the VPDBδ13C scale realisation, was introduced in 2006. In 2015, itsδ13C value was found to be drifting and, in 2017, its use as an RM forδ13C was officially discontinued by IUPAC. New RMs of low uncertainty are needed. This paper describes the preparation and characterisation of IAEA‐610, IAEA‐611 and IAEA‐612 (calcium carbonate, of chemical origin) which shall serve as a set of RMs aimed at anchoring the VPDB scale at negativeδ13C values.

Methods

The preparation and characterisation of IAEA‐610, IAEA‐611 and IAEA‐612 were performed by addressing the contemporary technical requirements for RM production and characterisation (ISO Guide 35:2017). The three RMs were produced in large quantities, and the first batch was sealed into ampoules (0.5 g) to ensure the integrity of the RM during storage; additional batches were sealed for long‐term storage. The most accurate method of CO2preparation and stable isotope measurements was used, namely carbonate‐H3PO4reaction under well‐controlled conditions combined with well‐tested stable isotope ratio mass spectrometry.

Results

The assigned values ofδ13C and associated uncertainties are based on a large number of analyses (~10 mg aliquots) performed at IAEA and address all the known uncertainty components. For aliquots down to ~100 μg, theδ13C uncertainty is increased. The uncertainty components considered are as follows: (i) material homogeneity, (ii) value assignment against IAEA‐603, (iii) potential storage effects, (iv) effect of the17O correction, and (v) mass spectrometer linearity and cross‐contamination memory in the ion source.

Conclusions

The new RMs IAEA‐610, IAEA‐611 and IAEA‐612 have been characterised on the VPDBδ13C scale in a mutually consistent way. The use of three RMs will allow a consistent realisation of the VPDBδ13C scale with small uncertainty to be established, and to reach metrological compatibility of measurement results over several decades.
Sliding mode control for systems subjected to unmatched disturbances/unknown control direction and its application
Authors: Guo Zongyi , Guo Jianguo , Wang Xinming , Chang Jing , Huang He
Published: December 2020

This article investigates the control issue for systems subjected to unmatched disturbances and unknown control direction simultaneously. A class of adaptive nonlinear disturbance observer is developed to estimate the unmatched disturbances precisely and then extended to the general high‐order form. The proposed method guarantees the stability of the second‐order and high‐order system under unknown control direction and robustness against the unmatched disturbances with the help of the sliding mode technique. The application in the integrated missile guidance and control (IGC) system design demonstrates the validity of the proposed control method. Herein, the cause of unknown control direction and the influence of the time‐vary control gain on the missile are discussed in detail. Also, the Monte Carlo campaign is run to show the superiority of the developed control strategy compared with the existing IGC method.
Testing linear inequalities of subgraph statistics
Authors: Gishboliner Lior , Shapira Asaf , Stagni Henrique
Published: December 2020

Property testers are fast randomized algorithms whose task is to distinguish between inputs satisfying some predetermined property and those that are far from satisfying it. A landmark result of Alon et al. states that for any finite family of graphs , the property of being induced ‐free (i.e., not containing an induced copy of any ) is testable. Goldreich and Shinkar conjectured that one can extend this by showing that for any linear inequality involving the densities of the graphs in the input graph, the property of satisfying this inequality is testable. Our main result in this paper disproves this conjecture. The proof deviates significantly from prior nontestability results in this area. The main idea is to use a linear inequality relating induced subgraph densities in order to encode the property of being a quasirandom graph.
Effect of Solution Temperature on Cold Rolling Properties of Lean Duplex Stainless Steel
Authors: Zhang Qirui , Li Jingyuan , Chen Yulai , Li Wang , Gao Zhijun
Published: December 2020

The effect of solution temperature on cold rolling properties of lean duplex stainless steel (LDSS) was studied. The cold‐rolling test was used to observe the crack of the material after solution at different temperatures; the work hardening curve of the solution treated material was obtained by compression test at room temperature, and the austenite element in LDSS was calculated by Thermo‐Calc software. The different element contents obviously affect the stacking fault energy (SFE) of the materials, which leads to the change of the difficulty of transformation induced martensite in austenite. The phase transformation induced plasticity (TRIP) effect in LDSS was analyzed by optical microscopy (OM), transmission electron microscopy (TEM), and electron backscatter diffraction (EBSD). It is found that different solution temperature can significantly affect the grain size of austenite, and then affect the difficulty of strain‐induced martensitic transformation (SIMT) of austenite grain in LDSS. When solution treated at 900–1100 °C, with the increase of temperature, the content of quenched martensite decreases, the amount of austenite which can induce transformation induced plasticity increases, and the rolling performance improve. However, when the temperature is higher than 1200 °C, Cr2N phase precipitates in ferrite, which reduces the plasticity of the material.
On a new test of fit to the beta distribution
Authors: Ebner Bruno , Liebenberg Shawn C.
Published: December 2020

We propose a new L2‐type goodness‐of‐fit test for the family of beta distributions based on a conditional moment characterization. The asymptotic null distribution is identified, and since it depends on the underlying parameters, a parametric bootstrap procedure is proposed. Consistency against all alternatives that satisfy a convergence criterion is shown, and a Monte Carlo simulation study indicates that the new procedure outperforms most of the classical tests. Finally, the procedure is applied to a real data set related to air humidity.
Basic pharmacological mechanisms and clinical evidence of the efficacy of hochuekkito against infectious diseases and its potential for use against COVID‐19
Authors: Takayama Shin , Kikuchi Akiko , Makino Toshiaki , Kainuma Mosaburo , Namiki Takao , Ito Takashi
Published: December 2020

Background

Hochuekkito extract (HET) has multiple effects through the digestive and immune systems, including for acute viral infection and chronic inflammation. We review basic pharmacological and clinical researches of HET and discuss the effects of HET against the pandemic COVID‐19.

Methods

We reviewed pharmacological studies from 1996 to 30 April 2020 that used experimental animals orally treated with HET and randomized controlled trials (RCTs) from 2000 to 30 April 2020.

Results

Altogether, 64 pharmacological studies reported immuno‐stimulatory effects against infection and cancer, immuno‐modulative effects against allergy and some inflammatory diseases, and ameliorating effects against exhaustion and frailty. Nine RCTs showed improvement of pulmonary Mycobacterium avium complex disease on chest X‐ray; improved systemic inflammation, nutrition, and quality of life of patients with chronic obstructive pulmonary disease and a decrease in the number getting common cold and exacerbations; reduction of soluble interleukin‐2 receptor and the serum cortisol concentration of postoperative patients; a reduction of the incidence of inflammatory complications and C‐reactive protein elevation after cerebrovascular disease; a reduction of the volume of steroid and tacrolimus during the treatment of atopic dermatitis; a healing effect for intractable chronic wounds; improvement of the physical status of elderly weak patients; and improvement of the fatigue level of cancer patients.

Conclusion

CODIV‐19 is characterized by high risk for the aged and people with other disease complications, cytokine hyperactivity in the severe stage, and sequelae in the recovery stage. Considering the immune‐stimulative/modulative effects of HET on inflammatory conditions and against exhaustion and frailty, it may be useful for prevention, treatment, and recovery from COVID‐19.
Utilizing the weak P−Cr bond in [{Cp*Cr(CO)3}2(μ,η1:1−P4)] for the generation of different P4 butterfly compounds
Authors: Grünbauer R. , Seidl M. , Balázs G. , Scheer M.
Published: December 2020

A novel reactivity of [{Cp*Cr(CO)3}2(μ,η1:1−P4)] (Cp*=C5Me5; 1) is reported, which utilizes the selective cleavage of the two P−Cr bonds and subsequently initiates a substituent exchange yielding P4 butterfly compounds. By means of NMR and IR spectroscopy studies, the successful implementation of 1 to obtain [{Cp′′′Fe(CO)2}2(μ,η1:1−P4)] (Cp′′′=C5H2tBu3; 2) and Cp′′′2P4 (3) could be confirmed, by reacting 1 with 2.0 eq. of K[Cp′′′Fe(CO)2] or NaCp′′′, respectively. Hereby, a quantitative conversion could be detected alongside the formation of 2.0 eq. of the [Cp*Cr(CO)3]− anion. Moreover, various syntheses of novel organometallic and organo‐P4 butterfly compounds were examined and first results show that the generation of different compounds should be possible. However, the isolation and stabilization of these sensitive molecules proves to be a major challenge.