bluuebunny/crossref_metadata_2025 huggingface dataset:
MiR396‐GRF module associates with switchgrass biomass yield and feedstock quality
Authors: Liu Yanrong , Yan Jianping , Wang Kexin , Li Dayong , Yang Rui , Luo Hong , Zhang Wanjun
Published: February 2021

Improving plant biomass yield and/or feedstock quality for highly efficient lignocellulose conversion has been the main research focus in genetic modification of switchgrass (Panicum virgatum L.), a dedicated model plant for biofuel production. Here, we proved that overexpression of miR396 (OE‐miR396) leads to reduced plant height and lignin content mainly by reducing G‐lignin monomer content. We identified nineteen PvGRFs in switchgrass and proved thirteen of them were cleaved by miR396. MiR396‐targeted PvGRF1, PvGRF9 and PvGRF3 showed significantly higher expression in stem. By separately overexpressing rPvGRF1, 3 and 9, in which synonymous mutations abolished the miR396 target sites, and suppression of PvGRF1/3/9 activity via PvGRF1/3/9‐SRDX overexpression in switchgrass, we confirmed PvGRF1 and PvGRF9 played positive roles in improving plant height and G‐lignin content. Overexpression of PvGRF9 was sufficient to complement the defective phenotype of OE‐miR396 plants. MiR396‐PvGRF9 modulates these traits partly by interfering GA and auxin biosynthesis and signalling transduction and cell wall lignin, glucose and xylan biosynthesis pathways. Moreover, by enzymatic hydrolysis analyses, we found that overexpression of rPvGRF9 significantly enhanced per plant sugar yield. Our results suggest that PvGRF9 can be utilized as a candidate molecular tool in modifying plant biomass yield and feedstock quality.
Social distancing predicts suicide rates: Analysis of the 1918 flu pandemic in 43 large cities, research note
Authors: Stack Steven , Rockett Ian R. H.
Published: February 2021

Social distancing (e.g., school and business closings) has been emphasized in current sociopolitical efforts in controlling COVID‐19. Such policies are assumed to increase suicide risk through lowering social integration. While two studies have linked the presence of a pandemic to suicide rates, no study has assessed the degree of social distancing on suicide rates during a pandemic. The present study fills this gap with data on the extent of social distancing during the Spanish flu epidemic in 43 large cities. The results find that increasing social distancing increases suicide rates independent of the influenza mortality rate.
Introducing the Psychological Autopsy Methodology Checklist
Authors: Conner Kenneth R. , Chapman Benjamin P. , Beautrais Annette L. , Brent David A. , Bridge Jeffrey A. , Conwell Yeates , Falter Tyler , Holbrook Amanda , Schneider Barbara
Published: February 2021

Objective

Case–control psychological autopsy studies are the research standard for the postmortem, quantitative study of ongoing or recent risk factors for suicide. We aimed to develop a reliable checklist of methodological quality of these studies.

Method

We adapted items from a validated checklist to address general methodological elements and created novel items to address the unique aspects of psychological autopsy research to generate a 16‐item checklist assessing reporting, external validity, internal validity, and power. We used percent agreement and kappa to evaluate inter‐rater reliability of the items and overall checklist based on independent ratings of 26 case–control psychological autopsy studies conducted internationally. We also summed the items to generate overall quality ratings, assessing internal consistency with coefficient alpha (α).

Results

Inter‐rater reliability for the overall checklist was high (percent agreement, 86.5%) and that based conservatively on kappa was substantial (κ .71) whereas internal consistency was low (α = 0.56). The inter‐rater reliability of the individual items showed acceptable to high agreement.

Conclusion

A novel checklist provides a reliable means to assess the methodological quality of specific elements of quantitative case–control psychological autopsy studies, providing detailed guidance in planning such studies. Lower internal consistency may limit its utility as a summary measure of study quality.
Life in the laparoscopic fast lane: evidence‐based perioperative management and enhanced recovery in benign gynaecological laparoscopy
Authors: Bryant‐Smith Alison , As‐Sanie Sawsan , Lloyd Jillian , Wong Maggie
Published: February 2021

Key content

Enhanced recovery after surgery (ERAS) protocols aim to shorten the length of hospital stay and expedite recovery, without increasing complications or readmission rates.

Implementation of ERAS protocols should be evidence‐based, including when applied to pre‐admission clinic (including preoperative investigations), fasting, antibiotic prophylaxis, thromboprophylaxis, analgesia, expeditious removal of urinary catheters and early mobilisation.

Learning objectives

To understand evidence‐based perioperative management of patients undergoing laparoscopic procedures for benign gynaecological indications.

To appraise critically the judicious ordering of preoperative investigations.

To understand the importance of preoperatively assessing and managing each patient’s risk of venous thromboembolism.

To understand the key components of perioperative management that decrease surgical site infection(s).

Ethical issues

Preoperative patient education is a vital component of perioperative management; written materials should be prepared in languages other than English to enable all patients to benefit from the ERAS approach.

A balance must be found between applying ERAS protocols as a checklist to ensure all aspects of patient care have been considered and tailoring those protocols to each patient’s individual needs.
Correcting US payments imbalances: Taxing foreign holders of its treasury securities is better than import tariffs
Authors: Hallwood Clifford Paul
Published: February 2021

To correct US current account deficits, dollar depreciation rather than imposition of tariffs is economically the better response. The theory of second best (The Review of Economic Studies, 24, 11) implies that if there is only one distortion then correct it, but the welfare effects of adding a second, supposedly offsetting distortion, may not increase welfare and can reduce it. In the context of an overvalued dollar caused by the dollar's status as the predominant global investment currency—a distortion adversely affecting the US manufacturing sector, the first best policy is not to impose tariffs because this adds a trade distortion on top of an exchange rate distortion and can easily be welfare reducing. US imports may be diverted from China to higher‐cost foreign producers not subjected to the tariff, and tariffs do nothing to promote US exports. The first best policy is directly to reduce the distortion of an overvalued exchange by discouraging excessive accumulation of foreign holdings of US securities held as foreign exchange reserves and by foreign private investors. A tax on the foreign holdings is a way to accomplish this.
Sensitivity and specificity of a shortened elimination diet protocol for the diagnosis of food‐induced atopic dermatitis (FIAD)
Authors: Fischer Nina , Spielhofer Leonie , Martini Franco , Rostaher Ana , Favrot Claude
Published: February 2021

Background

The gold standard to diagnose food allergy in dogs is an eight week elimination diet trial (EDT) followed by a re‐challenge. A recent study demonstrated that a shorter EDT is possible if prednisolone is administered initially.

Hypothesis/Objectives

The goal was to evaluate the sensitivity and specificity of the EDT based on the number of relapses after prednisolone discontinuation. In addition, the aim was to determine whether the initial treatment length or the replacement of prednisolone with oclacitinib would influence the outcome.

Animals

Eighty‐seven dogs with atopic dermatitis.

Methods and materials

Dogs were fed an elimination diet and treated with either prednisolone or oclacitinib for two to three weeks. Relapsing dogs were treated a second time. In the absence of a relapse after two weeks off medication, dogs then were challenged. Dogs never achieving two weeks off treatment without relapse received the regular EDT.

Results

Fifty‐eight of 87 dogs completed the study. Thirty‐nine of 58 dogs received prednisolone; 21 of these were diagnosed with FIAD and had no relapse (n = 14), one relapse (n = 6) or two relapses (n = 1). Nineteen of 58 dogs received oclacitinib; 11 of these were deemed food‐allergic and had no relapse (n = 7) or two relapses (n = 4). The initial treatment duration did not influence the outcome. The threshold of one relapse or less for the diagnosis of FIAD was associated with a sensitivity of 95% for prednisolone and 63% for oclacitinib. The specificity was 100% for both drugs.

Conclusion and clinical importance

Initial prednisolone or oclacitinib use in EDT shortens the time to diagnosis of FIAD.
Pulsed Suction Control in a Highly Loaded Compressor Cascade With Low Suction Flowrates
Authors: Zhang Hongxin , Chen Shaowen
Published: February 2021

The influence of pulsed suction (PS) on flow separation and aerodynamic performance in a highly loaded compressor cascade is experimentally studied herein. The excitation frequency is investigated as it determines the effectiveness of PS in flow control. Low suction flowrates are examined to analyze the potential of PS in providing a satisfactory cascade performance. For comparison, the corresponding parameters of steady continuous suction (SCS) are studied as well. Oil-flow visualizations and steady and unsteady pressure data are used to characterize the control effects of SCS and PS. The experimental results validate the efficacy of PS in controlling flow separation, even at a reduced suction flowrate of 0.1%. It suppresses passage vortex (PV), improving aerodynamic performance. PS provides a better control effect than SCS at different excitation parameters, which can be attributed to twofold main reasons: first, at the same suction flowrate, PS has a larger suction momentum than SCS during the suction phase, resulting in a stronger suction force and having a more profound effect on the flow characteristics; and second, owing to the introduction of pulsed excitation to the suction, PS creates additional vortex structures that energize the boundary layer by transporting high momentum freestream fluid near the wall. PS is also effective at a higher incidence angle, but its control effect is reduced.
Experimental Investigation of Film Cooling Performance on Blade Endwall With Diffusion Slot Holes and Stator–Rotor Purge Flow
Authors: Yu Zhiqiang , Liu Jianjun , Li Chen , An Baitao , Xu Guangyao
Published: February 2021

This paper focuses on the influences of the discrete-hole shape and layout on the blade endwall film cooling effectiveness. The effect of upstream purge slot injection on the film cooling performance of the discrete hole was also investigated. The diffusion slot hole was first applied to the blade endwall. As a comparison, the cooling performance of the fan-shaped hole was also measured. Totally, six discrete-hole cooling configurations (two hole shapes × three layouts) were investigated. Experiments were performed in a seven-blade linear cascade with the exit Reynolds number of 2.64 × 105. The average blowing ratios (BR) of the discrete holes changed from 0.5 to 2.5, and the coolant mass flow ratio of the purge slot (MFR) was fixed at MFR = 1.5%. The distributions of the cooling effectiveness on the blade endwall were measured by the pressure-sensitive paint technique. Results indicate that the diffusion slot hole significantly increases the film cooling effectiveness on the blade endwall compared to the fan-shaped hole, especially at a high blowing ratio. The maximum relative increment of the cooling effectiveness is over 40%. The layout with the discrete holes arranged lining up with the tangent direction of the blade profile offset curves exhibits a comparable film cooling effectiveness with the layout with the discrete holes arranged according to the cross-flow direction. The film cooling effectiveness on the pressure surface corner is remarkably enhanced by deflecting the hole orientation angle toward the pressure surface. The combination of purge slot and diffusion slot holes supplies a full-coverage film cooling for the entire blade endwall at MFR = 1.5% and BR = 2.5. In addition, the slot injection leads to a non-negligible influence on the cooling performance of the discrete holes near the separation line.
Analysis of Fluid Flow in the Sealing Gap of Radial Shaft Seals and Elastic Deformation of the Sealing Surface
Authors: Schulz Markus , Hagmayer Marius , Baumann Matthias , Bauer Frank
Published: February 2021

The function of a radial shaft seal is based on interactions between the sealing edge and the shaft counterface. To better understand these mechanisms, a look inside the sealing contact was taken. The procedure and the testing facility are presented in this article. In addition, a research methodology was developed to systematically analyze the fluid flow and the distortion of the sealing surface of shaft seals. The results of the test procedure are documented in an evaluation matrix that allows the comparison of sealing systems with different worn sealing edges. For example, the tests show an influence of the rotation direction of the shaft during running-in on the formation of leakage channels or oil collecting chambers within the sealing contact.
Experimental Data Mining Research on Factors Influencing Friction Coefficient of Wet Clutch
Authors: Wu Bangzhi , Qin Datong , Hu Jianjun , Liu Yonggang
Published: February 2021

In this study, an experiment is conducted for assessing the friction characteristics of a wet clutch on actual working conditions, to determine how various factors influence the friction coefficient in the actual working process of a wet clutch. Based on the experimental data of a wet clutch under different engagement conditions, a data surrogate model construction method is proposed for the friction coefficient. According to this model, the decoupling between different influencing factors of friction coefficient is realized, and their influence on friction coefficient is obtained. To reveal the change mechanism of the friction coefficient, a theoretical analysis model of the friction coefficient is established by using the elastic contact theory and the elastic fluid dynamic pressure lubrication theory. In addition, based on the constructed friction coefficient data surrogate model, the sensitivity of different influencing factors on the friction coefficient and the coupling relationship between the different influencing factors are studied.
Applying Social Cognition Models to Explain Walking Duration in Older Adults: The Role of Intrinsic Motivation
Authors: Labudek Sarah , Fleig Lena , Jansen Carl-Philipp , Kramer-Gmeiner Franziska , Nerz Corinna , Becker Clemens , Klenk Jochen , Schwenk Michael
Published: February 2021

This study examined the applicability of the health action process approach (HAPA) to walking duration in older adults and the added value of extending the HAPA by intrinsic motivation. Self-reports from older adults (N = 309; Mage = 78.7, 70–95 years) regarding activity-related intrinsic motivation and HAPA variables were collected at the baseline of a fall prevention intervention study. Walking duration at ≥3 metabolic equivalents of task was measured for 7 days via body-worn accelerometers. Two structural equation models with walking duration as a manifest outcome were specified. In both models, the model fit was acceptable, but intention and planning were not associated with walking duration. Intrinsic motivation was significantly related to most HAPA variables and walking duration. Variance explained for walking duration was R2 = .14 in the HAPA and R2 = .17 in the extended model. For explaining older adults’ walking duration, intrinsic motivation, but not HAPA-based intention and planning, seemed to be important.
Inch-sized high-quality perovskite single crystals by suppressing phase segregation for light-powered integrated circuits
Authors: Liu Yucheng , Zhang Yunxia , Zhu Xuejie , Yang Zhou , Ke Weijun , Feng Jiangshan , Ren Xiaodong , Zhao Kui , Liu Ming , Kanatzidis Mercouri G. , Liu Shengzhong (Frank)
Published: February 2021

Low-temperature solution–grown large high-quality perovskite single crystals enable integrated circuits for imaging.
Sulfated polysaccharide directs therapeutic angiogenesis via endogenous VEGF secretion of macrophages
Authors: Yu Yuanman , Dai Kai , Gao Zehua , Tang Wei , Shen Tong , Yuan Yuan , Wang Jing , Liu Changsheng
Published: February 2021

A synthetic sulfated chitosan induces macrophage-mediated functional angiogenesis in ischemia without an aid of exogenous GFs.
Bridging-induced phase separation induced by cohesin SMC protein complexes
Authors: Ryu Je-Kyung , Bouchoux Céline , Liu Hon Wing , Kim Eugene , Minamino Masashi , de Groot Ralph , Katan Allard J. , Bonato Andrea , Marenduzzo Davide , Michieletto Davide , Uhlmann Frank , Dekker Cees
Published: February 2021

Yeast cohesin complexes cluster onto long DNA into liquid droplets, which they accomplish by ATP-independent DNA bridging.
Draft Genome Sequences of
Pseudomonas
sp. Isolates Recovered from Ghanaian Fish Food Samples in 2018
Authors: Wessels Laura , Reich Felix , Schmoger Silvia , Pucher Johannes , Atter Amy , Käsbohrer Annemarie , Hammerl Jens Andre
Published: February 2021

The genus
Pseudomonas
represents a broad diversity of opportunistic and pathogenic species that are able to colonize a wide range of ecological niches. Here, we report on draft genome sequences of 35
Pseudomonas
sp. isolates that were recovered from small processed Ghanaian fishes offered at food markets in 2018.
Fault kinematics: A record of tectono-climatically controlled sedimentation along passive margins, an example from the U.S. Gulf of Mexico
Authors: Omale Abah P. , Lorenzo Juan M. , AlDhamen Ali , Clift Peter D. , Webb A. Alexander G.
Published: February 2021

Faults offsetting sedimentary strata can record changes in sedimentation driven by tectonic and climatic forcing. Fault kinematic analysis is effective at evaluating changes in sediment volumes at salt/shale-bearing passive margins where sediment loading drives faulting. We explore these processes along the northern Gulf of Mexico. Incremental throw along 146 buried faults studied across onshore Louisiana revealed continual Cenozoic fault reactivation punctuated by inactive periods along a few faults. Fault scarp heights measured from light detection and ranging (LiDAR) data are interpreted to show that Cenozoic fault reactivation continued through the Pleistocene.

The areas of highest fault throw and maximum sediment deposition shifted from southwest Louisiana in the early Miocene to southeast Louisiana in the middle–late Miocene. These changes in the locus of maximum fault reactivation and sediment deposition were controlled by changing tectonics and climate in the source areas. Early Miocene fault throw estimates indicate a depocenter farther east than previously mapped and support the idea that early Miocene Appalachian Mountain uplift and erosion routed sediment to southeast Louisiana.

By correlating changes in fault throw with changes in sediment deposition, we suggest that (1) fault kinematic analysis can be used to evaluate missing sediment volumes because fault offsets can be preserved despite partial erosion, (2) fault throw estimates can be used to infer changes in past tectonic and climate-related processes driving sedimentation, and (3) these observations are applicable to other passive margins with mobile substrates and faulted strata within overfilled sedimentary basins.
MRSA infection of masticatory spaces in a paediatric patient
Authors: Singh Anupam , Smriti Komal , Nayak Sunil , Gadicherla Srikanth
Published: February 2021

Diagnosis of source of maxillofacial infection in paediatric patients can be challenging due to difficulty in eliciting a proper history and multiple potential sources of infection. Identification and removal of the nidus of infection with decompression and institution of antibiotic therapy as per the culture-sensitivity report form the mainstay treatment of the infection. Deviation from it may result in persistence or even progression of infection, resulting in significant morbidity and mortality. In the past decade, the incidence of community-acquired methicillin-resistantStaphylococcus aureusinfection in the oral cavity has seen an upward trend. This has further led to an increase in complexity in the diagnosis of maxillofacial infections. In this case, the authors want to bring to light the challenges faced in managing a paediatric patient with persistent fascial space infection even after removal of the offending tooth, which signifies the importance of managing the infection by the time-tested protocol.
Identification of presumed corneal neuromas and microneuromas using laser-scanning in vivo confocal microscopy: a systematic review
Authors: Chinnery Holly Rose , Rajan Rajni , Jiao Haihan , Wu Mengliang , Zhang Alexis Ceecee , De Silva Manikkuwadura Eranda Harshan , Makrai Eve , Stepp Mary Ann , Di Girolamo Nick , Downie Laura Elizabeth
Published: February 2021

Background/aims

This systematic review critically evaluated peer-reviewed publications describing morphological features consistent with, or using terms related to, a ‘neuroma’ or ‘microneuroma’ in the human cornea using laser-scanning in vivo confocal microscopy (IVCM).

Methods

The review was prospectively registered on PROSPERO (CRD42020160038). Comprehensive literature searches were performed in Ovid MEDLINE, Ovid Embase and the Cochrane Library in November 2019. The review included primary research studies and reviews that described laser-scanning IVCM for examining human corneal nerves. Papers had to include at least one of a pre-specified set of keyword stems, broadly related to neuromas and microneuromas, to describe a corneal nerve feature.

Results

Twenty-five papers (20 original studies; 5 reviews) were eligible. Three original studies evaluated corneal nerve features in healthy eyes. Most papers assessed corneal nerves in ocular and systemic conditions; seven studies did not include a control/comparator group. There was overlap in terminology used to describe nerve features in healthy and diseased corneas (eg, bulb-like/bulbous, penetration, end/s/ing). Inspection of IVCM images within the papers revealed that features termed ‘neuromas’ and ‘microneuromas’ could potentially be physiological corneal stromal-epithelial nerve penetration sites. We identified inconsistent definitions for terms, and limitations in IVCM image acquisition, sampling and/or reporting that may introduce bias and lead to inaccurate representation of physiological nerve characteristics as pathological.

Conclusion

These findings identify a need for consistent nomenclature and definitions, and rigorous IVCM scanning and analysis protocols to clarify the prevalence of physiological, as opposed to pathological, corneal nerve features.
Sensory neuronopathies: new genes, new antibodies and new concepts
Authors: Fargeot Guillaume , Echaniz-Laguna Andoni
Published: February 2021

Degeneration of dorsal root ganglia (DRG) and its central and peripheral projections provokes sensory neuronopathy (SN), a rare disorder with multiple genetic and acquired causes. Clinically, patients with SN usually present with proprioceptive ataxia, patchy and asymmetric sensory abnormalities, widespread areflexia and no weakness. Classic causes of SN include cancer, Sjögren’s syndrome, vitamin deficiency, chemotherapy, mitochondrial disorders and Friedreich ataxia. More recently, new genetic and dysimmune disorders associated with SN have been described, includingRFC1gene-linked cerebellar ataxia, neuropathy and vestibular areflexia syndrome (CANVAS) and anti-FGFR3 antibodies. In this review, we detail the pathophysiology of DRG degeneration, and the genetic and acquired causes of SN, with a special focus on the recently described CANVAS and anti-FGFR3 antibodies. We also propose a user-friendly and easily implemented SN diagnostic strategy.
Sex differences for phenotype in pathologically defined dementia with Lewy bodies
Authors: Bayram Ece , Coughlin David G , Banks Sarah J , Litvan Irene
Published: February 2021

Introduction

Sex differences in dementia with Lewy bodies (DLB) have been reported in clinically defined cohorts; however, clinical diagnostic accuracy in DLB is suboptimal and phenotypic differences have not been assessed in pathologically confirmed participants.

Methods

Core DLB features were compared across 55 women and 156 men with pathologically defined DLB in the National Alzheimer’s Coordinating Center. These analyses were repeated for 55 women and 55 men matched for age, education and tau burden.

Results

In the total sample, women died older, had fewer years of education, had higher tau burden but were less likely to be diagnosed with dementia and clinical DLB. In the matched sample, visual hallucinations continued to be less common in women, and fewer women met clinical DLB criteria.

Discussion

Sex impacts clinical manifestations of underlying pathologies in DLB. Despite similar underlying Lewy body pathology, women are less likely to manifest core DLB features and may be clinically underdiagnosed.
Herbal smoking products: a systematic content analysis and mapping of the e-retail market
Authors: Gupta Arpit , Sharda Shweta , Yogitha Pothamsetty , Goel Sonu , Goyal Ashima , Gauba Krishan
Published: February 2021

Objective

To assess the online availability and e-marketing strategies of herbal smoking products (HSPs).

Methodology

Google, Yahoo and Bing were searched using relevant keywords related to HSPs. The first 50 records were retrieved and duplicates were removed. Two trained and calibrated authors screened the records according to the eligibility criteria and extracted data from each selected retail-webpage as per the pre-tested data extraction form.

Results

Out of the initial 1044 records obtained, 73 retail webpages were finally included. Most of the webpages about HSPs hailed from India followed by the USA. The results showed 24 brands with about 189 flavour variants that are readily available online to all age groups including minors, with price per pack (20 sticks) of herbal cigarettes ranging from INR (₹) 51 to 1830 (median 588). There are no regulations regarding the sale and marketing of HSPs concerning age restrictions and display of health warnings.

Conclusion

HSPs are readily available online at affordable prices and attractive variants for customers of all ages. The flavour appeal and the health benefit appeal is being used to target minors and young women. There is an urgent need for some regulations on the sale and e-marketing of such products that have an enormous potential to be used as a gateway to tobacco smoking.
Phenomenology of a supersymmetric model inspired by inflation
Authors: Hollik Wolfgang Gregor , Li Cheng , Moortgat-Pick Gudrid , Paasch Steven
Published: February 2021

The current challenges in high energy physics and cosmology are to build coherent particle physics models to describe the phenomenology at colliders in the laboratory and the observations in the universe. From these observations, the existence of an inflationary phase in the early universe gives guidance for particle physics models. We study a supersymmetric model which incorporates successfully inflation by a non-minimal coupling to supergravity and shows a unique collider phenomenology. Motivated by experimental data, we set a special emphasis on a new singlet-like state at$$97\,\text {GeV}$$97GeVand single out possible observables for a future linear collider that permit a distinction of the model from a similar scenario without inflation. We define a benchmark scenario that is in agreement with current collider and Dark Matter constraints, and study the influence of the non-minimal coupling on the phenomenology. Measuring the singlet-like state with high precision on the percent level seems to be promising for resolving the models, even though the Standard Model-like Higgs couplings deviate only marginally. However, a hypothetical singlet-like state with couplings of about$$20\,\%$$20%compared to a Standard Model Higgs at$$97\,\text {GeV}$$97GeVencourages further studies of such footprint scenarios of inflation.
Structure, ferroelectric and energy density properties of BaTiO3 film capacitors for energy storage applications
Authors: Zhang Min , Deng Chaoyong
Published: February 2021

Single-perovskite lead-free BaTiO3 ferroelectric films were synthesized on Nb:SrTiO3 substrates by pulsed laser deposition. The microstructure, ferroelectric, electric-field breakdown strength, and energy-storage properties of films were investigated. The remnant polarization [Formula: see text] reached the higher values of 34.79 [Formula: see text]C/cm2. The recoverable energy-storage density [Formula: see text] is 12.30 J/cm3. The results also reveal that rapid thermal processing (RTP) enhances the ferroelectric and energy storage properties of the film by comparison with unannealed, and ferroelectric and energy storage properties exhibit a strong voltage dependence.
Numerical simulation of rotating channel flow based on a modified DES model
Authors: Lin Peifeng , Wang Pu , Zhou Yong , Li Xiaojun
Published: February 2021

A new type of nonlinear sub-grid scale (SGS) model is adopted based on the helicity analysis and is verified by predicting the internal flow in a rotating channel. A stress term that contains helicity constraint is introduced into the original SGS model to construct a nonlinear sub-grid model. This additional term representing the helicity constraint effect in the momentum equations is shown to give predictions that are in better agreement with the experimental data. In this paper, the Detached-Eddy Simulation (DES) and the nonlinear SGS model are used to further study the turbulence statistics of the rotating channel flow. Combining with the Reynolds stress transport equations and the turbulent kinetic energy transport equation, the change of turbulence statistics near the wall of the rotating channel is analyzed. The newly added term changes the turbulent viscosity near the wall, which changes the velocity gradient near the wall and further affects other turbulence statistics near the wall.
Riemann–Hilbert approach and multi-soliton solutions of a variable-coefficient fifth-order nonlinear Schrödinger equation with N distinct arbitrary-order poles
Authors: Li Zhi-Qiang , Tian Shou-Fu , Zhang Tian-Tian , Yang Jin-Jie
Published: February 2021

Based on inverse scattering transformation, a variable-coefficient fifth-order nonlinear Schrödinger equation is studied through the Riemann–Hilbert (RH) approach with zero boundary conditions at infinity, and its multi-soliton solutions with [Formula: see text] distinct arbitrary-order poles are successfully derived. By deriving the eigenfunction and scattering matrix, and revealing their properties, a RH problem (RHP) is constructed based on inverse scattering transformation. Via solving the RHP, the formulae of multi-soliton solutions are displayed when the reflection coefficient possesses [Formula: see text] distinct arbitrary-order poles. Finally, some appropriate parameters are selected to analyze the interaction of multi-soliton solutions graphically.
New optical soliton solutions for Fokas–Lenells dynamical equation via two various methods
Authors: Seadawy Aly R. , Ali Khalid K. , Liu Jian-Guo
Published: February 2021

In this paper, we examine the Fokas–Lenells equation (FLE) that depicts the promulgation of ultra-short pulsation in visual fibers while confirming the terms of the following asymptotic arrangement beyond those indispensable for the nonlinear Schrödinger equation. In addition the model includes both spatio–temporal dispersal and self-steepening terms. Then, we discuss deep visual solutions of the FLE via taking the modified Kudryashov method and the extended tanh expansion method.
Study on low frequency sound insulation characteristic of thin acoustic black hole
Authors: Lian Xiao , Wang Shengsheng , Liu Maolin , Nie Songhui , Peng Jinfeng , Zhou Zhuo , Wu Jiu Hui
Published: February 2021

We use numerical and experimental methods to investigate the low frequency sound insulation characteristic of designed thin acoustic black hole (ABH). The numerical results show that the sound energy focusing effect plays a leading role in low frequency sound insulation of designed ABH, and the reflection at the edge of ABH is the main reason of sound insulation in medium and high frequencies. Experimental results display that the Sound Transmission Loss (STL) of the designed ABH is higher than 30 dB below 700 Hz, which shows that the isolated acoustic waves are more than 95%. The low frequency sound insulation performance of proposed ABHs is much better than the traditional acoustic materials, which has great potential applications for low frequency sound insulation.
Solution of two-qubit Rabi model with extended generalized rotating-wave approximation
Authors: Yan Zhanyuan , Qu Peihua , Xu Bingbing , Zhang Shihui , Ma Jinying
Published: February 2021

The generalized rotating-wave approximation (GRWA) method is extended to the two-qubit quantum Rabi model. In the first-order approximation (one photon exchange), the Hamiltonian matrix in photon number space is simplified by introducing two variational parameters. However, the Hamiltonian matrix is not a diagonalizable matrix yet. Furthermore, by presenting a constraint condition on coupling strength and atomic transition frequency, the Hamiltonian matrix is simplified and an effective solvable Hamiltonian with block diagonal form is obtained. In the even and odd parity space, the energy spectra and eigenstates of the two-qubit quantum Rabi model are achieved analytically. Most of the energy spectra, especially the lower energy levels, agree well with the numerical exact results in ultra-strong coupling region, and the ground state wave function can gives a fairly accurate result of mean photon number.
Low-Voltage Low-Power CMOS-Based Current-Mode Implementation of Digital Logic Gates and Combinational Circuits
Authors: Gupta Prabhat , Banerjee Raina , Sharma Ravish
Published: February 2021

In this paper, a new low-voltage low-power circuit is introduced for implementing CMOS-based basic logic functions using the analog current-mode techniques. The logic functions have been realized by using their expansion in Power Series representation, a Squaring circuit and a Geometric Mean circuit. To illustrate the proposed method, simultaneous realization of the basic logic functions NOT, OR, AND, XOR, NOR, NAND and XNOR in a single circuit is considered. Furthermore, these functions have been used to realize various combinational circuits including full-adder, full-subtractor, etc. SPICE simulation results, obtained with 1.5-V supply, are included.
An Improved Comparator Based on Current Reuse and a New Frequency Compensation Technique used in an OTA for Pipeline ADCs
Authors: Guermaz M. B. , Berbar T. B. , Lehouidj B. , Belaroussi M. T. , Bouzerara L.
Published: February 2021

In this paper, a comparator and an operational amplifier considered as essential components, constituting a 10-bit 50-MHz pipeline Analog-to-Digital Converter for Wireless Local Area Network (WLAN) applications, are described and designed. All post-layout and Monte-Carlo simulations, using a 0.35[Formula: see text][Formula: see text]m CMOS AMS process technology with [Formula: see text][Formula: see text]V supply voltage and an input common-mode range of [Formula: see text][Formula: see text]V, are achieved. An improved clocked comparator with a dynamic latch, based on a switched capacitor network, using the current reuse technique for slew rate enhancement and positive feedback for offset voltage compensation, is presented. The operational amplifier, consisting of a fully differential folded cascode operational transconductance amplifier, providing high-gain and good stability, is exhibited. A new frequency compensation technique, based on active resistors, is used to improve amplifier phase-margin. The Monte-Carlo performance results of the designed clocked comparator provide an offset voltage of [Formula: see text][Formula: see text]mV with [Formula: see text][Formula: see text]mV 3[Formula: see text] deviation, a slew rate of [Formula: see text]V/ns with [Formula: see text]V/ns 3[Formula: see text] deviation, and a propagation delay of [Formula: see text][Formula: see text]ns with [Formula: see text][Formula: see text]ns 3[Formula: see text] deviation. Monte-Carlo performance results of the designed operational amplifier provide a phase-margin of [Formula: see text], and a high-gain of [Formula: see text]dB with [Formula: see text] and [Formula: see text]dB 3[Formula: see text], respectively, by using [Formula: see text] load capacitance.
The stationary Boussinesq problem under singular forcing
Authors: Allendes Alejandro , Otárola Enrique , Salgado Abner J.
Published: February 2021

In Lipschitz two- and three-dimensional domains, we study the existence for the so-called Boussinesq model of thermally driven convection under singular forcing. By singular we mean that the heat source is allowed to belong to [Formula: see text], where [Formula: see text] is a weight in the Muckenhoupt class [Formula: see text] that is regular near the boundary. We propose a finite element scheme and, under the assumption that the domain is convex and [Formula: see text], show its convergence. In the case that the thermal diffusion and viscosity are constants, we propose an a posteriori error estimator and show its reliability. We also explore efficiency estimates.
Geometric linearization of theories for incompressible elastic materials and applications
Authors: Jesenko Martin , Schmidt Bernd
Published: February 2021

We derive geometrically linearized theories for incompressible materials from nonlinear elasticity theory in the small displacement regime. Our nonlinear stored energy densities may vary on the same (small) length scale as the typical displacements. This allows for applications to multiwell energies as, e.g. encountered in martensitic phases of shape memory alloys and models for nematic elastomers. Under natural assumptions on the asymptotic behavior of such densities we prove Gamma-convergence of the properly rescaled nonlinear energy functionals to the relaxation of an effective model. The resulting limiting theory is geometrically linearized in the sense that it acts on infinitesimal displacements rather than finite deformations, but will in general still have a limiting stored energy density that depends in a nonlinear way on the infinitesimal strains. Our results, in particular, establish a rigorous link of existing finite and infinitesimal theories for incompressible nematic elastomers.
Nonlinear Dynamic Analysis and Control of FG Cylindrical Shell Fitted with Piezoelectric Layers
Authors: Bayat Aliakbar , Jalali Amir , Ahmadi Habib
Published: February 2021

In this study, the nonlinear vibration control of functionally graded laminated piezoelectric cylindrical shells under simultaneous parametric axial and radial external excitations is presented. The partial differential equations of shells are derived based on Hamilton’s principle, first-order shear deformation theory (FSDT), and nonlinear von Karman relations. The coupled nonlinear ordinary differential equations are obtained by Galerkin’s procedure and solved by the method of static condensation. Two piezoelectric layers are placed on the outer and inner surfaces of the cylindrical shell each as distributed sensor and actuator. Then the constant-gain negative velocity feedback strategy is employed. Regarding the nonlinear equations of motion, for the first time, the vibration analysis and active vibration control of smart FG cylindrical shells under combined parametric and external excitations are analyzed using the multiple scales approach. The effects of various parameters such as power index, external excitation’s amplitude, and control gain on the dynamic behavior of the system are investigated, using bifurcation diagrams, phase portraits, time histories, and Poincare maps. It is shown that quasi-periodic motion is the most common behavior of the system and controller gain and power index have inevitable effects on enhancing the quasi-periodic response of the system. Care should be exerted in selecting the parameters to have the desired response in the broad range of excitation frequency.
Nanofibrous Filters for PM2.5 Filtration: Conception, Mechanism and Progress
Authors: Yin Ni , Liu Fujuan
Published: February 2021

Research of air filtration technology has been paid much attention due to the increasingly serious environmental problems. Till now, a great deal of work has been engaged in promoting the development of air filtration fields. However, the trade-off between the removal efficiency and the pressure drop remains challenging. Nanofibrous filters (NFFs), with the superiority of high surface energy, controllable porosity, good interconnected pore structure, and easily combining with other functional substances, are expected to achieve high efficiency and low resistance. In this paper, the filtration mechanisms of fibrous filters were presented, involving both mechanical adsorption and electrostatic adsorption. Besides, on the basis of the two mechanisms, the overview of structure-dependent and electrostatic-dependent NFFs was summarized separately in recent years, such as the component, preparation process and application performance, respectively. Finally, the development of nanofibrous membranes was prospected with the aim of providing directional guidance for improvement of air purification field.
Synthesis, Properties and Applications of Silica-Coated Magnetite Nanoparticles: A Review
Authors: Mamun Md Al , Rumi K. M. Jalal Uddin , Das Harinarayan , Hoque S. Manjura
Published: February 2021

Silica-Coated Magnetite nanoparticles (SMNP) recently gained much attractions in biomedical, environmental, construction and nuclear applications. SMNP can overcome the limitations of bare magnetic iron oxide nanoparticles (MNP) such as agglomeration, dissolution and leaching in aqueous and biological system. Silica coating protects the MNP core as well as provides excellent biocompatibility, chemical and thermal stability with higher adsorption capacity of heavy metals and radionuclides. SMNPs are mostly prepared by Modified Stöber method as the simplest route although surface pretreatment or surface modification is needed to avoid formation of large aggregates. Microemulsion method gives excellent size and shape control but needs large quantity of surfactants and solvents. Sonochemical approach provides faster hydrolysis and can prevent agglomeration without any surface pretreatment. Optimal silica coating thickness can provide uniform particles distribution, enough superparamagnetic properties for easy magnetic separation, chemical and thermal stability. Keeping in mind the wide interest in SMNP, this review is designed to report the important information on synthesis, properties and potential applications of SMNP.
Differentiation of different antifungals with various mechanisms using dynamic surface-enhanced Raman spectroscopy combined with machine learning
Authors: Li Hao , Cao Yongbing , Lu Feng
Published: February 2021

With the increase in mortality caused by pathogens worldwide and the subsequent serious drug resistance owing to the abuse of antibiotics, there is an urgent need to develop versatile analytical techniques to address this public issue. Vibrational spectroscopy, such as infrared (IR) or Raman spectroscopy, is a rapid, noninvasive, nondestructive, real-time, low-cost, and user-friendly technique that has recently gained considerable attention. In particular, surface-enhanced Raman spectroscopy (SERS) can provide a highly sensitive readout for bio-detection with ultralow or even trace content. Nevertheless, extra attachment cost, nonaqueous acquisition, and low reproducibility require the conventional SERS (C-SERS) to further optimize the conditions. The emergence of dynamic SERS (D-SERS) sheds light on C-SERS because of the dispensable substrate design, superior enhancement and stability of Raman signals, and solvent protection. The powerful sensitivity enables D-SERS to perform only with a portable Raman spectrometer with moderate spatial resolution and precision. Moreover, the assistance of machine learning methods, such as principal component analysis (PCA), further broadens its research depth through data mining of the information within the spectra. Therefore, in this study, D-SERS, a portable Raman spectrometer, and PCA were used to determine the phenotypic variations of fungal cells Candida albicans (C. albicans) under the influence of different antifungals with various mechanisms, and unknown antifungals were predicted using the established PCA model. We hope that the proposed technique will become a promising candidate for finding and screening new drugs in the future.
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Authors: Sanan David , Zhao Yongwang , Lin Shang-Wei , Yang Liu
Published: February 2021

To make feasible and scalable the verification of large and complex concurrent systems, it is necessary the use of compositional techniques even at the highest abstraction layers. When focusing on the lowest software abstraction layers, such as the implementation or the machine code, the high level of detail of those layers makes the direct verification of properties very difficult and expensive. It is therefore essential to use techniques allowing to simplify the verification on these layers. One technique to tackle this challenge is
top-down verification
where by means of simulation properties verified on top layers (representing abstract specifications of a system) are propagated down to the lowest layers (that are an implementation of the top layers). There is no need to say that simulation of concurrent systems implies a greater level of complexity, and having compositional techniques to check simulation between layers is also desirable when seeking for both feasibility and scalability of the refinement verification. In this article, we present
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a (compositional) rely-guarantee-based framework for the
top-down verification
of complex concurrent systems in the Isabelle/HOL theorem prover.
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uses CSimpl, a language with a high degree of expressiveness designed for the specification of concurrent programs. Thanks to its expressibility, CSimpl is able to model many of the features found in real world programming languages like exceptions, assertions, and procedures.
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provides a framework for the verification of rely-guarantee properties to compositionally reason on CSimpl specifications. Focusing on top-down verification,
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provides a simulation-based framework for the preservation of CSimpl rely-guarantee properties from specifications to implementations. By using the simulation framework, properties proven on the top layers (abstract specifications) are compositionally propagated down to the lowest layers (source or machine code) in each concurrent component of the system. Finally, we show the usability of
CSim

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by running a case study over two CSimpl specifications of an Arinc-653 communication service. In this case study, we prove a complex property on a specification, and we use
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to preserve the property on lower abstraction layers.