bluuebunny/crossref_metadata_2025 huggingface dataset:
Premature and Early Menopause in Relation to Cardiovascular Disease
Authors: Schipper Izaäk , Louwers Yvonne V.
Published: January 2021

Postmenopausal women have an increased risk for cardiovascular diseases. It has been postulated that the loss of ovarian function and subsequent deficiency of endogenous estrogens after menopause contributes to this elevated risk of cardiovascular disease in postmenopausal women. Compared with woman entering menopause at the mean age of 51 years, in women with early menopause or premature ovarian insufficiency the risk for cardiovascular disease is even greater. These women lack the cardioprotective effect of endogenous estrogens for many more years than do women entering natural menopause. The majority of data assessing the risk of cardiovascular disease in relation to age at menopause and specifically premature menopause are derived from large epidemiological cohort studies. In addition, observations in women undergoing bilateral oophorectomy at an early age provide convincing evidence regarding association between early menopause or POI and the development of cardiovascular events and mortality. Moreover, genetic variants associated with earlier age at menopause have also been found to increase the risk of cardiovascular events in women. It has been substantiated that hormone replacement therapy (HRT) decreases the risk for ischemic heart disease and eliminates the increased cardiovascular disease mortality. It is therefore crucial to start HRT as soon as possible, particularly in women with premature ovarian insufficiency.
Comparison of Cases with Anterior Cruciate Ligament Reconstruction Accompanied by Simultaneous Medial Meniscus Bucket Handle Tear Repair and Isolated Medial Meniscus Bucket Handle Tear Repair
Authors: Akalın Yavuz , Avcı Özgür , İnce Savaş İ. , Çevik Nazan , Şahin İsmail G. , Öztürk Alpaslan
Published: January 2021

The aim of this study was to evaluate the success of the all-inside repair technique for medial bucket-handle meniscus tear (BHMT) and the factors affecting healing. A total of 36 patients with BHMT who were operated between 2012 and 2018 and completed final follow-up examinations were included in the study. Functional evaluation was made with the International Knee Documentation Committee (IKDC) score, Lysholm score, and Tegner score. Healing was evaluated on magnetic resonance imaging (MRI) slices. The patients were evaluated with respect to the effect on healing of factors such as demographic data, body mass index (BMI), smoking status, anterior cruciate ligament tear reconstruction (ACLTR) applied at the same time as BHMT repair, and the tear being chronic or acute. The mean age of the patients was 28.6 ± 8.6 years (range,18–46 years), the mean follow-up period was 25.8 ± 13.9 months (range, 13–59 months), and BMI was mean 25.6 ± 3.5 kg/m2 (range, 20.1–30.5 kg/m2). The meniscus tears were acute in 16 (44.4%) patients and chronic in 20 (55.6%). ACLTR was applied together with BHMT repair in 25 patients. The hybrid technique, as the outside-in technique in addition to the all-inside technique, was applied to 12 (33.3%) patients, where there was seen to be extension to the anterior horn. The failure rate was determined as 27.8% according to the postoperative MRI evaluation and the Barrett criteria. No positive or negative statistically significant effect on healing was determined of chronic BHMT or of simultaneous application of ACLTR (p = 1.00 and 0.457, respectively). Cigarette smoking and high BMI were determined to have a statistically significant negative effect on healing (p = 0.026 and 0.007, respectively). In conclusion, it can be seen that the success of the all-inside technique for BHMT remains controversial. Due to the features of the application, it can be used in meniscus tears of the posterior horn only. In the current study, with the success rate of 72.2% of the all-inside technique in meniscus body tears, it was seen that a high success rate could not be achieved.
The Adjustment of the Rotational Alignment of the Distal End of the Extramedullary Guide to the Anteroposterior Axis of the Proximal Tibia in Total Knee Arthroplasty
Authors: Mizu-uchi Hideki , Kido Hidehiko , Chikama Tomonao , Kamo Kenta , Kido Satoshi , Nakashima Yasuharu
Published: January 2021

The optimal placement within 3 degrees in coronal alignment was reportedly achieved in only 60 to 80% of patients when using an extramedullary alignment guide for the tibial side in total knee arthroplasty (TKA). This probably occurs because the extramedullary alignment guide is easily affected by the position of the ankle joint which is difficult to define by tibial torsion. Rotational direction of distal end of the extramedullary guide should be aligned to the anteroposterior (AP) axis of the proximal tibia to acquire optimal coronal alignment in the computer simulation studies; however, its efficacy has not been proven in a clinical setting. The distal end of the guide can be overly displaced from the ideal position when using a conventional guide system despite the alignment of the AP axis to the proximal tibia. This study investigated the effect of displacement of the distal end of extramedullary guide relative to the tibial coronal alignment while adjusting the rotational alignment of the distal end to the AP axis of the proximal tibia in TKA. A total of 50 TKAs performed in 50 varus osteoarthritic knees using an image-free navigation system were included in this study. The rotational alignment of the proximal side of the guide was adjusted to the AP axis of the proximal tibia. The position of the distal end of the guide was aligned to the center of the ankle joint as viewed from the proximal AP axis (ideal position) and as determined by the navigation system. The tibial intraoperative coronal alignments were recorded as the distal end was moved from the ideal position at 3-mm intervals. The intraoperative alignments were 0.5, 0.9, and 1.4 degrees in valgus alignment with 3-, 6-, and 9-mm medial displacements, respectively. The intraoperative alignments were 0.7, 1.2, and 1.7 degrees in varus alignment with 3-, 6-, and 9-mm lateral displacements, respectively. In conclusion, the acceptable tibial coronal alignment (within 2 degrees from the optimal alignment) can be achieved, although some displacement of the distal end from the ideal position can occur after the rotational alignment of the distal end of the guide is adjusted to the AP axis of the proximal tibia.
Specific Cognitive Changes due to Hippocalcin Alterations? A Novel Familial Homozygous Hippocalcin Variant Associated with Inherited Dystonia and Altered Cognition
Authors: Siegert Sandy , Schmidt Wolfgang M. , Pletschko Thomas , Bittner Reginald E. , Gobara Sonja , Freilinger Michael
Published: January 2021

Background Recent research suggested an hippocalcin (HPCA)-related form of DYT2-like autosomal recessive dystonia. Two reports highlight a broad spectrum of the clinical phenotype. Here, we describe a novel HPCA gene variant in a pediatric patient and two affected relatives.

Methods Whole exome sequencing was applied after a thorough clinical and neurological examination of the index patient and her family members. Results of neuropsychological testing were analyzed.

Results Whole exome sequencing revealed a novel homozygous missense variant in the HPCA gene [c.182C>T p.(Ala61Val)] in our pediatric patient and the two affected family members. Clinically, the cases presented with dystonia, dysarthria, and jerky movements. We observed a particular cognitive profile with executive dysfunctions in our patient, which corresponds to the cognitive deficits that have been observed in the patients previously described.

Conclusion We present a novel genetic variant of the HPCA gene associated with autosomal recessive dystonia in a child with childhood-onset dystonia supporting its clinical features. Furthermore, we propose specific HPCA-related cognitive changes in homozygous carriers, underlining the importance of undertaking a systematic assessment of cognition in HPCA-related dystonia.
Initial Experience with the NAVIO Robotic-Assisted Total Knee Replacement—Coronal Alignment Accuracy and the Learning Curve
Authors: Collins Kade , Agius Paul A. , Fraval Andrew , Petterwood Josh
Published: January 2021

One of the primary aim of total knee arthroplasty (TKA) is restoration of the mechanical axis of the lower limb. Maintenance of the mechanical axis within 3 degrees of neutral has been shown to result in improved clinical results and implant longevity. The aim of this study was to investigate the efficacy of this robotic-assisted system in coronal plane component positioning in TKA. We also describe the learning curve associated with adoption of this technology. A total of 72 total knee replacements were completed between November 2017 and September 2018 by a single surgeon using the robotic-assisted surgery (RAS) system. Cases were recorded from the time the study surgeon first adopted this technology and represent the “learning curve.” Pre- and postoperative coronal weight-bearing alignments were measured and intraoperative robotic-assisted registration data and duration of use were collected. Of the 72 TKAs in this series, 93.3% were corrected to the desired alignment of within 3 degrees of neutral. The knees that were not corrected to neutral had a mean preoperative alignment of 11.57 degrees of deformity as compared with 4.29 degrees for those that were corrected to neutral. A learning curve effect during adoption of this new technology was not found when analyzing RAS usage time. The RAS system produced accurate coronal alignment in TKA in more than 93% of cases with no learning curve effect. Our study suggests that this system is easily adopted, safe, and accurate.
Mobile Stroke Units: Current and Future Impact on Stroke Care
Authors: Bowry Ritvij , Grotta James C.
Published: January 2021

Ischemic stroke is a leading cause of death and major disability that impacts societies across the world. Earlier thrombolysis of blocked arteries with intravenous tissue plasminogen activator (tPA) and/or endovascular clot extraction is associated with better clinical outcomes. Mobile stroke units (MSU) can deliver faster tPA treatment and rapidly transport stroke patients to centers with endovascular capabilities. Initial MSU trials in Germany indicated more rapid tPA treatment times using MSUs compared with standard emergency room treatment, a higher proportion of patients treated within 60 minutes of stroke onset, and a trend toward better 3-month clinical outcomes with MSU care. In the United States, the first multicenter, randomized clinical trial comparing standard versus MSU treatment began in 2014 in Houston, TX, and has demonstrated feasibility and safety of MSU operations, reliability of telemedicine technology to assess patients for tPA eligibility without additional time delays, and faster door-to-groin puncture times of MSU patients needing endovascular thrombectomy in interim analysis. Scheduled for completion in 2021, this trial will determine the cost-effectiveness and benefit of MSU treatment on clinical outcomes compared with standard ambulance and hospital treatment. Beyond ischemic stroke, MSUs have additional clinical and research applications that can profoundly impact other cohorts of patients who require time-sensitive neurological care.
Assessment of Depression, Anxiety, and Sleep Disturbance in COVID-19 Patients at Tertiary Care Center of North India
Authors: Yadav Ramakant , Yadav Prashant , Kumar Sushil Shukla , Kumar Raj
Published: January 2021

Background and Objective The novel Coronavirus pandemic surfaced in Wuhan, China in December 2019 and spread rapidly across the globe. In recent available literature, most of the studies were done to estimate the burden of psychiatric problems among general population due to this pandemic, Therefore, this study was planned to assess depression, anxiety, and sleep disturbance among Coronavirus disease-2019 (COVID-19) patients.

Materials and Methods A hospital-based, cross-sectional study was done from June 2020 to August 2020 among 100 COVID-19 patients who were admitted and fulfilled the inclusion criteria. Assessment of depression, anxiety, and sleep disturbance were done by patient health questionnaire-9 (PHQ-9) scale, generalized anxiety disorder-7 (GAD-7) scale and Pittsburg sleep quality index (PSQI), respectively.

Results In this study, 73% were males and 27% were females. The mean age of the patients in present study was 42.90 ± 16.33 years. This study reveals that depression was in 27%, anxiety in 67%, and sleep disturbance in 62% of patients. Depression and anxiety were found significantly associated with presence of comorbidity and severity of illness (p < 0 0.05). The association of sleep disturbance with severity of illness was also found statistically significant (p < 0.05).

Conclusion The risk of psychological stress is high in COVID-19 patients. The psychological problems among COVID-19 patients are commonly related to the consequences of disease, and severity and contagiousness of the disease. Therefore, in this present pandemic situation, it is more important to identify these psychological problems among COVID-19 patients, so that better care and timely interventions can be done with respect to psychological issues.
Radiofrequency Rejuvenation of the “Tweener” Patient: Under, Over, or Through the Skin
Authors: Kam Joanna , Frost Ariel , Bloom Jason D.
Published: January 2021

The demand for noninvasive facial rejuvenation continues to increase as younger, well-informed patients enter the aesthetic market. We refer to a subset of these patients as “tweeners,” those who present with early signs of neck and facial aging, but who have not yet developed changes significant enough to warrant a traditional excisional surgery approach. Many of these patients are in search of a minimally invasive intervention, a bridge in between observation and surgery. The authors describe their experience with radiofrequency (RF) technology as an in-office tool to address the aging face in a select patient population. This review also attempts to comprehensively search the existing body of literature to describe the RF technologies and devices available for facial rejuvenation. The efficacy and safety profiles of the devices are discussed, and the devices are categorized by their method of RF delivery—over (contact), through (microneedle), and under (percutaneous) the skin.
Deep-learning-based nanowire detection in AFM images for automated nanomanipulation
Authors: Bai Huitian , Wu Sen
Published: January 2021

Atomic force microscope (AFM)-based nanomanipulation has been proved to be a possible method for assembling various nanoparticles into complex patterns and devices. To achieve efficient and fully automated nanomanipulation, nanoparticles on the substrate must be identified precisely and automatically. This work focuses on an autodetection method for flexible nanowires using a deep learning technique. An instance segmentation network based on You Only Look Once version 3 (YOLOv3) and a fully convolutional network (FCN) is applied to segment all movable nanowires in AFM images. Combined with follow-up image morphology and fitting algorithms, this enables detection of postures and positions of nanowires at a high abstraction level. Benefitting from these algorithms, our program is able to automatically detect nanowires of different morphologies with nanometer resolution and has over 90% reliability in the testing dataset. The detection results are less affected by image complexity than the results of existing methods and demonstrate the good robustness of this algorithm.
Shot noise limited soft x-ray absorption spectroscopy in solution at a SASE-FEL using a transmission grating beam splitter
Authors: Engel Robin Y. , Ekimova Maria , Miedema Piter S. , Kleine Carlo , Ludwig Jan , Ochmann Miguel , Grimm-Lebsanft Benjamin , Ma Rory , Teubner Melissa , Dziarzhytski Siarhei , Brenner Günter , Czwalinna Marie Kristin , Rösner Benedikt , Kim Tae Kyu , David Christian , Herres-Pawlis Sonja , Rübhausen Michael , Nibbering Erik T. J. , Huse Nils , Beye Martin
Published: January 2021

X-ray absorption near-edge structure (XANES) spectroscopy provides element specificity and is a powerful experimental method to probe local unoccupied electronic structures. In the soft x-ray regime, it is especially well suited for the study of 3d-metals and light elements such as nitrogen. Recent developments in vacuum-compatible liquid flat jets have facilitated soft x-ray transmission spectroscopy on molecules in solution, providing information on valence charge distributions of heteroatoms and metal centers. Here, we demonstrate XANES spectroscopy of molecules in solution at the nitrogen K-edge, performed at FLASH, the Free-Electron Laser (FEL) in Hamburg. A split-beam referencing scheme optimally characterizes the strong shot-to-shot fluctuations intrinsic to the process of self-amplified spontaneous emission on which most FELs are based. Due to this normalization, a sensitivity of 1% relative transmission change is achieved, limited by fundamental photon shot noise. The effective FEL bandwidth is increased by streaking the electron energy over the FEL pulse train to measure a wider spectral window without changing FEL parameters. We propose modifications to the experimental setup with the potential of improving the instrument sensitivity by two orders of magnitude, thereby exploiting the high peak fluence of FELs to enable unprecedented sensitivity for femtosecond XANES spectroscopy on liquids in the soft x-ray spectral region.
Limitations of Hartree–Fock with quantum resources
Authors: Gulania Sahil , Whitfield James Daniel
Published: January 2021

The Hartree–Fock problem provides the conceptual and mathematical underpinning of a large portion of quantum chemistry. As efforts in quantum technology aim to enhance computational chemistry algorithms, the Hartree–Fock method, central to many other numerical approaches, is a natural target for quantum enhanced algorithms. While quantum computers and quantum simulation offer many prospects for the future of modern chemistry, the non-deterministic polynomial-complete Hartree–Fock problem is not a likely candidate. We highlight this fact from a number of perspectives including computational complexity, practical examples, and the full characterization of energy landscapes for simple systems.
Linear simulation of kinetic electromagnetic instabilities in a tokamak plasma with weak magnetic shear
Authors: Zhao Yunchuan , Wang Jiaqi , Liu Dongjian , Chen Wei , Dong Ge , Lin Zhihong
Published: January 2021

Gyrokinetic simulation and eigenvalue calculation of electromagnetic instabilities are carried out for an experimentally observed low-n mode in weak magnetic shear discharge. With different magnetic shear values, the Gyrokinetic Toroidal Code simulation of the ion temperature gradient mode is consistent with the eigenvalue code (HD7) calculation. Due to the sensitivity of the kinetic ballooning mode (KBM) to global equilibrium, the simulation of the KBM deviates from the eigenvalue results, for the ballooning representation used in HD7 satisfies its spatial scale separations. Under a flat safety factor profile, the KBM is more unstable and its mode structure tends to move with the peak of the ion temperature drive. Further simulation of the KBM in an HL-2A-like equilibrium shows that the β excitation threshold of the mode is lower than 0.2% and the dominant toroidal mode number is n = 4, which is consistent with the measured experimental spectrum.
Ionic self-diffusion coefficient and shear viscosity of high-Z materials in the hot dense regime
Authors: Hou Yong , Jin Yang , Zhang Ping , Kang Dongdong , Gao Cheng , Redmer Ronald , Yuan Jianmin
Published: January 2021

High-Z materials exhibit a broad range of variation of the charge state in the hot dense regime, and so ionic structures become complex with increasing density and temperature owing to ionization. Taking high-Z uranium as example, we study its electronic and ionic structures in the hot dense regime by combining an average-atom model with the hypernetted chain approximation. The electronic structure is described by solving the Dirac equation, taking account of relativistic effects, including broadening of the energy levels, and the effect of other ions via correlation functions. On the basis of the electronic distribution around a nucleus, the ion pair potential is constructed using the modified Gordon–Kim model in the frame of temperature-dependent density functional theory. Because of the presence of ion–ion strong coupling, the bridge function is included in the hypernetted chain approximation, which is used to calculate the correlation functions. To take account of the influence on transport properties of the strong correlation of electrons with highly charged ions, we perform both classical and Langevin molecular dynamics simulations to determine ion self-diffusion coefficients and the shear viscosity, using the Green–Kubo relation and an ion–ion pair potential with good convergence. We show that the influence of electron–ion collisions on transport properties becomes more important as the free electron density increases owing to thermal ionization.
Application of Nomarski interference system in supersonic gas-jet target diagnosis
Authors: Liu Qiushi , Ma Mingjiang , Zhang Xiaohua , Zhao Baozhen , Lv Chong , Meng Xianghao , Wang Zhao , He Chuangye , Tian Baoxian , Xi Xiaofeng , Liu Fulong , Guo Bing
Published: January 2021

Supersonic gas-jet target performs an important role in laser wakefield acceleration, and its density diagnosis is a significant part of target characteristic study. In this paper, a Mach–Zehnder and Nomarski interference system is set up and used for gas-jet target density diagnosis. We have investigated and compared the performance of the Mach–Zehnder part and Nomarski part. The feasibility of the Nomarski interferometer with vertical fringes has been verified. Moreover, it shows better stability and has a more compact structure, beneficial for obtaining more accurate and effective target density characterization in laser wakefield acceleration.
Critical benchmarking of popular composite thermochemistry models and density functional approximations on a probabilistically pruned benchmark dataset of formation enthalpies
Authors: Das Sambit Kumar , Chakraborty Sabyasachi , Ramakrishnan Raghunathan
Published: January 2021

First-principles calculation of the standard formation enthalpy, ΔHf° (298 K), in such a large scale as required by chemical space explorations, is amenable only with density functional approximations (DFAs) and certain composite wave function theories (cWFTs). Unfortunately, the accuracies of popular range-separated hybrid, “rung-4” DFAs, and cWFTs that offer the best accuracy-vs-cost trade-off have until now been established only for datasets predominantly comprising small molecules; their transferability to larger systems remains vague. In this study, we present an extended benchmark dataset of ΔHf° for structurally and electronically diverse molecules. We apply quartile-ranking based on boundary-corrected kernel density estimation to filter outliers and arrive at probabilistically pruned enthalpies of 1694 compounds (PPE1694). For this dataset, we rank the prediction accuracies of G4, G4(MP2), ccCA, CBS-QB3, and 23 popular DFAs using conventional and probabilistic error metrics. We discuss systematic prediction errors and highlight the role an empirical higher-level correction plays in the G4(MP2) model. Furthermore, we comment on uncertainties associated with the reference empirical data for atoms and the systematic errors stemming from these that grow with the molecular size. We believe that these findings will aid in identifying meaningful application domains for quantum thermochemical methods.
Generation of excited species in a streamer discharge
Authors: Dhali Shirshak K.
Published: January 2021

At or near atmospheric pressure, most transient discharges, particularly in molecular gases or gas mixture containing molecular gases, result in a space charge dominated transport called a streamer discharge. The excited species generation in such discharges forms the basis for plasma chemistry in most technological applications. In this paper, we simulate the propagation of streamers in atmospheric pressure N2 to understand the energy partitioning in the formation of various excited species and compare the results to a uniform Townsend discharge. The model is fully two-dimensional with azimuthal symmetry. The results show a significantly larger fraction of the energy goes into vibrational excitation of the N2 ground state in a streamer-type discharge in comparison to a Townsend discharge. For lower applied voltages, the anode-directed (negative) steamer is slightly more efficient in channeling energy for excited species production in comparison to a cathode-directed (positive) streamer. Near 70% overvoltage, both types of streamers show very similar energy partitioning, but quite different from a Townsend discharge.
Aeroacoustic modal analysis of underexpanded pipe jets with and without an upstream cavity
Authors: Baskaran Kabilan , Srinivasan K.
Published: January 2021

The investigation of the aeroacoustics of an underexpanded pipe-cavity jet is carried out experimentally. Two different aspect ratios of the cavity are tested for a wide range of nozzle pressure ratios. Both internal and externally radiated pipe-cavity acoustics are studied. Linear and higher-order spectral analyses are implemented on the unsteady cavity pressure to comprehend the nature of the cavity acoustics and nonlinear interactions of different acoustic modes of the pipe–cavity system. Results show that an increase in depth leads to an enhancement in the nonlinear interactions. Furthermore, the power spectral and overall sound pressure level analyses of pipe and pipe-cavity jet noise radiation are carried out. High-speed schlieren imaging techniques are used to understand jet dynamics. Highly unsteady motion of the jet initial shear layer is observed due to an upstream disturbance of the cavity. In addition, proper orthogonal and dynamic mode decomposition methods are used to extract the spatial and dynamic modes of the jet structure. These methods are used to segregate the cavity associated jet dynamics and screech dynamics.
Effective photocatalytic water splitting enhancement using GaN/ZnO/NiO core/shell nanocolumns
Authors: Wang Junfei , Xi Xin , Lin Shan , Li Xiaodong , Hu Tiangui , Zhao Lixia
Published: January 2021

In this study, the GaN/ZnO heterojunction and ZnO–NiO p–n junction core/shell nanocolumns were fabricated based on GaN nanocolumns. During the water splitting measurements, the photocurrent of GaN/ZnO/NiO (GZN) nanocolumns is 2.1 times higher than that of GaN nanocolumns. The enhancement is mainly due to the heterojunction between GaN and ZnO and the p–n junction between ZnO and NiO, which build strong built-in electric fields to accelerate the separation of photogenerated carriers. Besides, the refractive index of NiO and ZnO is smaller than that of GaN, which can facilitate the light absorption of GZN nanocolumns and improve the water splitting performance. Our work has greatly improved the photocatalytic efficiency of GaN for water splitting applications.
Noise reduction mechanism of airfoils with leading-edge serrations and surface ridges inspired by owl wings
Authors: Wang Lei , Liu Xiaomin , Li Dian
Published: January 2021

The remarkable characteristics of the silent flight of owls provide infinite inspiration for the low-noise operation of the rotating impeller machinery. However, how the characteristics of owl wings, including the leading-edge serrations, trailing-edge serrations, and plumed surfaces, affect the aerodynamic noise has not been studied comprehensively. According to previous research, the noise reduction level of an airfoil with an extensive sinusoidal profile is limited to a certain degree. In this paper, as a new coupling element, the surface ridge of owl wings is added to the airfoils with leading-edge serrations. Based on the NACA0012 (National Advisory Committee for Aeronautics) airfoil, the bionic airfoils with sinusoidal, serrated, and iron-shaped leading-edge serrations and surface ridges are reconstructed and studied to reveal the noise reduction mechanism of the coupled elements. The hybrid numerical method of large eddy simulation combined with the acoustic analog equations is adopted to predict the far-field acoustic characteristics. The vortex dynamic method is used to exposit the noise reduction mechanism of biomimetic flow control. The results demonstrate that the airfoil with iron-shaped leading-edge serrations has the best effect of noise reduction. Relative to the original airfoil, the sound pressure level is reduced by 14.3 dB. The change of streamwise vortices caused by the biomimetic structures leads the regular large-scale tubular vortices to separate into smaller horseshoe vortices. In addition, the correlation coefficient of spanwise is reduced, and the change of time-averaged vorticity in the space field promotes the attenuation effect of sound source caused by sound pressure fluctuation radiation.
Pressure distribution and flow dynamics in a nasal airway using a scale resolving simulation
Authors: Van Strien James , Shrestha Kendra , Gabriel Sargon , Lappas Petros , Fletcher David F. , Singh Narinder , Inthavong Kiao
Published: January 2021

Airflow through the nasal cavity exhibits a wide variety of fluid dynamic behaviors due to the intricacy of the nasal geometry. The flow is naturally unsteady and perhaps turbulent, despite Computational Fluid Dynamics (CFD) in the literature being assumed as having a steady laminar flow. Time-dependent simulations can be used to generate detailed data with the potential to uncover new flow behavior, although they are more computationally intensive than steady-state simulations. Furthermore, verification of CFD results has relied on a reported pressure drop (e.g., nasal resistance) across the nasal airway although the geometries used are different. This study investigated the unsteady nature of inhalation at flow rates of 10 l/min, 15 l/min, 20 l/min, and 30 l/min. A scale resolving CFD simulation using a hybrid Reynolds-averaged Navier–Stokes--large eddy simulation model was used and compared with experimental measurements of the pressure distribution and the overall pressure drop in the nasal cavity. The experimental results indicated a large pressure drop across the nasal valve and across the nasopharynx, with the latter attributed to a narrow cross-sectional area. At a flowrate of 30 l/min, the CFD simulations showed that the anterior half of the nasal cavity displayed dominantly laminar but disturbed flow behavior in the form of velocity fluctuations. The posterior half of the nasal cavity displayed turbulent activity, characterized by erratic fluctuating velocities, which was enhanced by the wider cross-sectional areas in the coronal plane. At 15 l/min, the flow field was laminar dominant with very little disturbance, confirming a steady-state laminar flow assumption is viable at this flow rate.
Exceeding 400% tunnel magnetoresistance at room temperature in epitaxial Fe/MgO/Fe(001) spin-valve-type magnetic tunnel junctions
Authors: Scheike Thomas , Xiang Qingyi , Wen Zhenchao , Sukegawa Hiroaki , Ohkubo Tadakatsu , Hono Kazuhiro , Mitani Seiji
Published: January 2021

Giant tunnel magnetoresistance (TMR) ratios of 417% at room temperature (RT) and 914% at 3 K were demonstrated in epitaxial Fe/MgO/Fe(001) exchange-biased spin-valve magnetic tunnel junctions (MTJs) by tuning growth conditions for each layer, combining sputter deposition for the Fe layers, electron-beam evaporation of the MgO barrier, and barrier interface tuning. Clear TMR oscillation as a function of the MgO thickness with a large peak-to-valley difference of ∼80% was observed when the layers were grown on a highly (001)-oriented Cr buffer layer. Specific features of the observed MTJs are symmetric differential conductance (dI/dV) spectra for the bias polarity and plateau-like deep local minima in dI/dV (parallel configuration) at |V| = 0.2–0.5 V. At 3 K, fine structures with two dips emerge in the plateau-like dI/dV, reflecting highly coherent tunneling through the Fe/MgO/Fe. We also observed a 496% TMR ratio at RT by a 2.24 nm-thick-CoFe insertion at the bottom-Fe/MgO interface.
Permittivity order modulation by intrinsic dielectric coupling
Authors: Yang Qirui , Li Yongqiang , Zhang Jiarui , Qi Qi , Chen Kai , Wang Ying , Liu Junming , Zhu Jinsong
Published: January 2021

The room-temperature permittivity is reduced by one order of magnitude in a wide frequency range during each step, when the stoichiometric proportion of Cu in CaCu3Ti4O12 is decreased from 3 to 2 and then to 1. The frequency-independent reduction can be applied down to 140 K. Such an almost frequency- and temperature-independent decrease in the permittivity magnitude order suggests the existence of intrinsic dielectric coupling between binary dielectric polarization species, by which the less polaron-like 3d electrons from B-site copper ions more strongly depress the permittivity contribution from one-dimensional, anti-parallel, mutually independent, and finite length dipole chains of thermally activated off-center displacements of A-site titanium ions.
Viscoelasticity of biomolecular condensates conforms to the Jeffreys model
Authors: Zhou Huan-Xiang
Published: January 2021

Biomolecular condensates, largely by virtue of their material properties, are revolutionizing biology, and yet, the physical understanding of these properties is lagging. Here, I show that the viscoelasticity of condensates can be captured by a simple model, comprising a component where shear relaxation is an exponential function (with time constant τ1) and a component with nearly instantaneous shear relaxation (time constant τ0 → 0). Modulation of intermolecular interactions, e.g., by adding salt, can disparately affect the two components such that the τ1 component may dominate at low salt, whereas the τ0 component may dominate at high salt. Condensates have a tendency to fuse, with the dynamics accelerated by interfacial tension and impeded by viscosity. For fast-fusion condensates, shear relaxation on the τ1 timescale may become rate-limiting such that the fusion speed is no longer in direction proportion to the interfacial tension. These insights help narrow the gap in understanding between the biology and physics of biomolecular condensates.
Electroluminescence from 4-nitroaryl organic color centers in semiconducting single-wall carbon nanotubes
Authors: Xu Beibei , Wu Xiaojian , Kim Mijin , Wang Peng , Wang YuHuang
Published: January 2021

Organic color-centers (OCCs) on single-wall carbon nanotubes are quantum defects that demonstrate intriguing near-infrared emission properties with potential for bioimaging, chemical sensing, and quantum communication. Many of these applications will require electrical pumping rather than optical excitation to deterministically access the near-infrared emission properties of OCCs, though this has yet to be achieved. In this work, we report experimental observation of near-infrared electroluminescence from 4-nitroaryl OCCs intentionally introduced on (6,5)-single-wall carbon nanotubes that are aligned across a pair of gold electrodes. Spatially correlated photoluminescence and electroluminescence spectroscopy reveal direct evidence of the localized electroluminescence from the OCCs on the semiconducting nanotube hosts. The electroluminescence intensity displays an exponential dependence on the source–drain current, suggesting that impact excitation by unipolar carriers at the quantum defects is the origin of the observed emission. These electroluminescent quantum defects may pave the way to enable on-chip integration for potential applications of OCCs in display, sensor, and spin-based devices, as well as other quantum technologies.
Quality adjusted life years in the time of COVID-19
Authors: Hall Jane , Viney Rosalie
Published: January 2021

The quality adjusted life year (QALY) as a basis of valuing additional expenditure on health is widely accepted. Although early in the COVID-19 pandemic, several commentators called for a similar approach in resolving trade-offs between economic activity and reducing the burden of COVID-19, this has not occurred. The value of a QALY has not been used to deny all intervention, as the rule of rescue attests. Further, while there was no other way of managing the pandemic, there were other means available to mitigate the economic losses. Now that vaccine programs have commenced in several countries, it is interesting to consider whether economic evaluation should now be applied. However, the recognised complexities of the evaluation of vaccines, plus the challenge of measuring opportunity costs in the face of an economic recession and the severity of the consequences of an outbreak even though the probability of transmission is exceedingly low, mean its use will be restricted. COVID-19 has changed everything, even the way we should think about economic evaluation.
Proteinaceous and humic fluorescent components in chloroform-fumigated soil extracts: implication for microbial biomass estimation
Authors: Rinot Oshri , Rotbart Nativ , Borisover Mikhail , Bar-Tal Asher , Oren Adi
Published: January 2021

Excitation–emission matrix fluorescence spectroscopy coupled with parallel factor analysis was employed for characterisation of chloroform fumigation-extractable soil organic matter, commonly used for soil microbial biomass estimation. This allowed, for the first time, to discriminate between humic-like (i.e. noncellular) and microbial protein-like, fumigation-extractable components, challenging the presumption that only microbial constituents contribute to the fumigation flush of C serving as a proxy measure for soil microbial C. A Vertisol was assayed under increasing K2SO4 extractant molarity (0–0.5 M), which allowed increasing organic matter extractability levels and the association of these increases with relative contributions from microbial versus humic sources. Expectedly, protein-like fluorescence was found negligible in the nonfumigated soil extracts while comprising the bulk of fluorescence of the material becoming K2SO4-extractable due to fumigation. Nevertheless, fumigation also led to an increase in extractable concentrations of humic-like components, showing that not only microbial constituents were fumigation-extractable. Humic-like fluorescence in the fumigation flush generally increased with decreasing K2SO4 molarity, being minimal at 0.25 M K2SO4. Considering also the preference for maximal flush of extractable soil organic matter, indicative of maximal fumigation efficiency, the use of 0.25 M K2SO4 seems preferable for extraction of microbial biomass with minimal interference from humic substances, for the investigated Vertisol. The presented working framework for assessment and alleviation of interference from humic substances in microbial biomass estimation is recommended to be applied specifically to any soil type before routine monitoring.
A glycan FRET assay for detection and characterization of catalytic antibodies to theCryptococcus neoformanscapsule
Authors: Crawford Conor J. , Wear Maggie P. , Smith Daniel F. Q. , d’Errico Clotilde , McConnell Scott A. , Casadevall Arturo , Oscarson Stefan
Published: January 2021

Significance

Cryptococcus neoformansis a global fungal pathogen that is a frequent cause of a life-threatening meningoencephalitis. There is a need for new therapies and vaccines. A better understanding of antibodies associated with its major virulence factor, the capsule, will allow the development of new antibody therapeutics, inform vaccine design, and further basic knowledge of antibody structure-function. Here, we demonstrate several antibodies against the capsule have innate glycosidase activity, and these antibodies can cause hydrolysis of the native capsule. This catalytic activity results in a disruption of cellular integrity and increased ease of phagocytosis by macrophages. To date, identifying this elusive quality in antibodies has been difficult. We have simplified this process by the development of a high-throughput FRET assay. This approach could be generalized to identify other antibodies catalytic against glycans.
The cognitive poetics of English-Chinese advertisement translation
Authors: Cui Ying
Published: January 2021

Advertisements often use poetic methods to increase aesthetic value, evoke emotion, and strengthen recipients’ impression. This study explores the cognitive poetics of English-Chinese advertisement translation and investigates how poetic methods are treated in translation. It draws upon poetics, psychology, and translation to study a corpus of 198 English-Chinese poetic advertisements. Two major poetic methods in the advertising discourse – repetition and image establishment – will be outlined, as well as their functions in invoking an emotional response and lasting impression. Then, analysis of a representative example will demonstrate how the poetic elements are transferred across languages, and the results of two surveys confirm their effects. The discussion is intended to shed light on the audience’s reception and perception of advertisements and provide translators with practical reference regarding poetic methods and the importance of the audience’s emotion and impression.
Influence of aerosol injection on the liquid chemistry induced by an RF argon plasma jet
Authors: Sremački Ivana , Bruno Giuliana , Jablonowski Helena , Leys Christophe , Nikiforov Anton , Wende Kristian
Published: January 2021

A radio-frequency driven plasma jet in annular geometry coupled with an aerosol injection into the effluent is proposed for the controllable reactive oxygen species (ROS)/reactive nitrogen species (RNS) production and delivery on biological targets in the context of plasma medicine, e.g. wound care. The role of the aqueous aerosol in modulating the reactive species production is investigated by combining physical and chemical analytics. Optical emission spectroscopy, electron paramagnetic resonance spectroscopy, and a biochemical model based on cysteine as a tracer molecule have been applied, revealing that aerosol injection shifts the production of ROS from atomic and singlet oxygen toward hydroxyl radicals, which are generated in the droplets. Species generation occurred mainly at the droplets boundary layer during their transport through the effluent, leading to a limited cysteine turnover upon introduction into the aerosol solution. The subsequent delivery of unmodified cysteine molecules at a target suggested the application of the plasma source for the topical delivery of drugs, expanding the potential applicability and effectiveness. The presence of RNS was negligible regardless of aerosol injection and only traces of the downstream products nitrate and nitrate were detected. In summary, the aerosol injection into the effluent opens new avenues to control UV radiation and reactive species output for the biomedical applications of non-thermal plasma sources, reaching out toward the regulation, safety, and efficacy of targeted applications.
The dependence of the emission from MQWs on the indium content in the underlying InGaN templates: experimental and modeling results
Authors: Abdelhamid Mostafa , Routh Evyn L , Bedair S M
Published: January 2021

The effect of underlying highly relaxed In
y
Ga1-y
N templates on In
x
Ga1-x
N multiple quantum wells (MQWs), where x> y, is investigated. Photoluminescence (PL) measurements and tested light emitting diodes (LEDs) show that relaxed In
y
Ga1-y
N templates with y ∼ 10% can cause a red shift in MQWs emission of

Δ

E
∼
0.33

eV

. This red shift is attributed to the reduced strain in the MQWs, resulting in a decrease in the MQWs band gap, along with an increase in indium incorporation in the QWs due to composition pulling effect. Theoretical modeling was applied to study the effect of the template’s indium content and its degree of relaxation on the observed red shift in MQW emission. The proposed model uses the PL emission data from the MQW to predict the indium content in the MQWs grown on GaN and on InGaN templates. Using this model, we are able to predict the dependence of both the amount of the red shift and the indium incorporation enhancement in the QWs on the In-content in the underlying templates. We are not aware of any similar modeling activities that reported such predictions. LED devices were fabricated using the In
y
Ga1-y
N templates and compared to conventional LED structure grown on GaN, showing a red shift in electroluminescence that agrees with the PL results.
Polydopamine–cellulose nanofiber composite for flexible electrode material
Authors: Muthoka Ruth M , Roy Sunanda , Kim Hyun Chan , Yoon Hargsoon , Zhai Lindong , Kim Jaehwan
Published: January 2021

This research is intended to develop a flexible and dopamine-based electrode material by blending polydopamine (PDA) with cellulose nanofiber (CNF). Inspired by its unique adhesion behavior, dopamine, a biomimetic protein, was utilized to form a strong adhesion between the CNFs. Herein, we report PDA concentration’s effect to produce PDA-CNF composite showing good electrochemical redox response, good mechanical properties, and improved thermal stability. The PDA-CNF composite with CNF:PDA = 5:2.5 showed the highest Young’s modulus, the strain at break, and toughness among other CNF:PDA combination composites. A PDA-CNF working electrode was made using a microfabrication process. Cyclic voltammetry analysis showed high ion permeability through the CNF backbone structure and oxidation process by PDA in PDA-CNF electrode. These findings indicate the feasibility of the PDA-CNF composite for enhanced longevity in flexible electrode applications utilizing the combination of high mechanical flexibility and thermal stability.
Odd-frequency pair density wave correlations in underdoped cuprates
Authors: Chakraborty Debmalya , Black-Schaffer Annica M
Published: January 2021

Pair density waves, identified by Cooper pairs with finite center-of-mass momentum, have recently been observed in copper oxide based high T
c superconductors (cuprates). A charge density modulation or wave is also ubiquitously found in underdoped cuprates. Within a general mean-field one-band model we show that the coexistence of charge density waves (CDWs) and uniform superconductivity in d-wave superconductors like cuprates, generates an odd-frequency spin-singlet pair density wave, in addition to the even-frequency counterparts. The strength of the induced odd-frequency pair density wave depends on the modulation wave vector of the CDW, with the odd-frequency pair density waves even becoming comparable to the even-frequency ones in parts of the Brillouin zone. We show that a change in the modulation wave vector of the CDW from bi-axial to uni-axial, can enhance the odd-frequency component of the pair density waves. Such a coexistence of superconductivity and uni-axial CDW has already been experimentally verified at high magnetic fields in underdoped cuprates. We further discuss the possibility of an odd-frequency spin-triplet pair density wave generated in the coexistence regime of superconductivity and spin density waves, applicable to the iron-based superconductors. Our work thus presents a route to bulk odd-frequency superconductivity in high T
c superconductors.