bluuebunny/crossref_metadata_2025_split huggingface dataset:
Clinical and Imaging Profile of Patients with Palatal Tremor
Authors: Surisetti Bharath Kumar , Prasad Shweta , Holla Vikram V. , Neeraja Koti , Kamble Nitish , Netravathi Manjunath , Yadav Ravi , Pal Pramod Kumar 
Published: February 2021

ABSTRACTBackgroundPalatal tremor (PT) is an uncommon movement disorder that may be classified into symptomatic (SPT) or essential (EPT). The etiology of SPT is varied, with involvement of the Guillain‐Mollaret triangle (GMT) and inferior olivary hypertrophy. EPT is associated with ear clicks and normal imaging and may have a functional basis.ObjectivesThis study aims to explore the clinical and radiological features of a large cohort of patients with PT.MethodsThis is a retrospective chart review of patients with PT who were evaluated by the movement disorders subspeciality of the neurology department. Demographic, clinical, and imaging details of patients with PT were documented.ResultsA total of 22 patients with PT comprising 17 with SPT and 5 with EPT were included in this study. No patient was aware of the PT. Ear clicks were reported in 2 patients with SPT and in 3 patients with EPT. The most common etiology for SPT was vascular, followed by degenerative conditions. Patients with SPT had associated features such as tremor (70.6%), ataxia (64.7%), dystonia (52.9%), myoclonus (17.6%), and eye movement abnormalities (75%). Lesions involving the GMT were found in 82% of patients with SPT. Apart from PT, patients with EPT had no other motor symptoms, and imaging was normal. Of the patients with EPT, 2 had additional functional movement disorders.ConclusionPT has significant etiological heterogeneity and can be easily missed because of the lack of awareness by patients. Involvement of the inferior olivary nucleus may not be necessarily observed. A functional etiology should be considered in cases of EPT.
Compact omnidirectional dual‐band dipole antenna with reduced ground plane effect
Authors: Zhang Kai , Yan Sen 
Published: February 2021

AbstractIn this letter, a compact omnidirectional dual‐band antenna is designed for wireless local area network applications. The proposed antenna is printed on the two sides of an FR4 substrate that the total dimension is 12 × 46 × 0.5 mm3. A dipole antenna is used to cover the lower operating band (2.45 GHz), while a capacitances‐loaded patch generates a higher resonance (5.5 GHz). This antenna has a good impedance matching in the operation band, and the gain is 2.28 and 4.42 dBi in the lower and upper bands, respectively. To address the problem that the performance will drastically decline when the antenna is located on a ground, a quarter wavelength spiral line is employed to decrease the negative effect of the ground. Two proposed dipole antennas, placed on a horizontal ground as a MIMO antenna system, are analyzed with different configurations. The results reveal that the proposed method can effectively reduce the ground plane effect and improve the diversity performance, which has huge potential applications in MIMO system.
DIR‐DBTnet: Deep iterative reconstruction network for three‐dimensional digital breast tomosynthesis imaging
Authors: Su Ting , Deng Xiaolei , Yang Jiecheng , Wang Zhenwei , Fang Shibo , Zheng Hairong , Liang Dong , Ge Yongshuai 
Published: February 2021

PurposeThe goal of this study is to develop a three‐dimensional (3D) iterative reconstruction framework based on the deep learning (DL) technique to improve the digital breast tomosynthesis (DBT) imaging performance.MethodsIn this work, the DIR‐DBTnet is developed for DBT image reconstruction by mapping the conventional iterative reconstruction (IR) algorithm to the deep neural network. By design, the DIR‐DBTnet learns and optimizes the regularizer and the iteration parameters automatically during the network training with a large amount of simulated DBT data. Numerical, experimental, and clinical data are used to evaluate its performance. Quantitative metrics such as the artifact spread function (ASF), breast density, and the signal difference to noise ratio (SDNR) are measured to assess the image quality.ResultsResults show that the proposed DIR‐DBTnet is able to reduce the in‐plane shadow artifacts and the out‐of‐plane signal leaking artifacts compared to the filtered backprojection (FBP) and the total variation (TV)‐based IR methods. Quantitatively, the full width half maximum (FWHM) of the measured ASF from the clinical data is 27.1% and 23.0% smaller than those obtained with the FBP and TV methods, while the SDNR is increased by 194.5% and 21.8%, respectively. In addition, the breast density obtained from the DIR‐DBTnet network is more accurate and consistent with the ground truth.ConclusionsIn conclusion, a deep iterative reconstruction network, DIR‐DBTnet, has been proposed for 3D DBT image reconstruction. Both qualitative and quantitative analyses of the numerical, experimental, and clinical results demonstrate that the DIR‐DBTnet has superior DBT imaging performance than the conventional algorithms.
Radiation dose calculation in 3D heterogeneous media using artificial neural networks
Authors: Keal James , Santos Alexandre , Penfold Scott , Douglass Michael 
Published: February 2021

PurposeExternal beam radiotherapy (EBRT) treatment planning requires a fast and accurate method of calculating the dose delivered by a clinical treatment plan. However, existing methods of calculating dose distributions have limitations. Monte Carlo (MC) methods are accurate but can take too long to be clinically viable. Deterministic approaches are quicker but can be inaccurate under certain conditions, particularly near heterogeneities and air interfaces. Neural networks trained on MC‐derived data have the potential to reproduce dose distributions that agree closely with the MC method while being significantly quicker to deploy.MethodsIn this work we present a framework for training machine learning models capable of directly calculating the dose delivered to a point in three‐dimensional (3D) heterogeneous media given only spatially local information. The framework consists of three parts. First, we describe a novel method of randomly generating 3D heterogeneous geometries using simplex noise. Dose distributions for training were obtained by importing these geometries into a MC simulation. The second and third parts of the framework are precalculated data channels, aligned with the patient computed tomography (CT) image, to be used as input to the model. These data channels are a computationally efficient way of encoding the parameters of an incident radiation beam while also allowing the model to learn from data that would otherwise be outside of its receptive field.ResultsWe demonstrate the viability of the framework by a training small, fully connected neural network model to reproduce dose distributions from megavoltage photon beams. The trained network displayed excellent agreement with MC dose distributions in randomly generated geometries with an average gamma index (3%/3 mm) pass rate of 94.7% and an average error of 1.45% of peak dose. Finally, the network was used to calculate the dose in a patient CT image, on which the network was not trained, producing similarly impressive results.ConclusionsA novel method of generating training data for learned radiation dosimetry models has been introduced, along with preprocessing steps that allow even simple models to reproduce accurate dose distributions for EBRT. More importantly, we have demonstrated that a model trained using the proposed framework can generalize from the training data to predicting the therapeutic dose in realistic media.
Gastrointestinal 4D MRI with respiratory motion correction
Authors: Johansson Adam , Balter James M. , Cao Yue 
Published: February 2021

PurposeGastrointestinal motion patterns such as peristalsis and segmental contractions can alter the shape and position of the stomach and intestines with respect to other irradiated organs during radiation therapy. Unfortunately, these deformations are concealed by conventional four‐dimensional (4D)‐MRI techniques, which were developed to visualize respiratory motion by binning acquired data into respiratory motion states without considering the phases of GI motion. We present a method to reconstruct breathing‐compensated images showing the phases of periodic gastric motion and study the effect of this motion on regional anatomical structures.MethodsSixty‐seven DCE‐MRI examinations were performed on patients undergoing MRI simulation for hepatocellular carcinoma using a golden‐angle stack‐of‐stars sequence that collected 2000 radial spokes over 5 min. The collected data were reconstructed using a method with integrated respiratory motion correction into a time series of 3D image volumes without visible breathing motion. From this series, a gastric motion signal was extracted by temporal filtering of time–intensity curves in the stomach. Using this motion signal, breathing‐corrected back‐projection images were sorted according to the gastric phase and reconstructed into 21 gastric motion state images showing the phases of gastric motion.ResultsReconstructed image volumes showed gastric motion states clearly with no visible breathing motion or related artifacts. The mean frequency of the gastric motion signal was 3 cycles/min with a standard deviation of 0.27 cycles/min.ConclusionsPeriodic gastrointestinal motion can be visualized without confounding respiratory motion using the presented GI 4D MRI technique. GI 4D MRIs may help define internal target volumes for treatment planning, aid in planning organ at risk volume definition, or support motion model development for gastrointestinal motion tracking algorithms for real‐time MR‐guided radiation therapy.
Dual‐excitation flip‐angle simultaneous cine and T1 mapping using spiral acquisition with respiratory and cardiac self‐gating
Authors: Zhou Ruixi , Weller Daniel S. , Yang Yang , Wang Junyu , Jeelani Haris , Mugler John P. , Salerno Michael 
Published: February 2021

PurposeTo develop a free‐breathing cardiac self‐gated technique that provides cine images and slice profile–corrected T1 maps from a single acquisition.MethodsWithout breath‐holding or electrocardiogram gating, data were acquired continuously on a 3T scanner using a golden‐angle gradient‐echo spiral pulse sequence, with an inversion RF pulse applied every 4 seconds. Flip angles of 3° and 15° were used for readouts after the first four and second four inversions. Self‐gating cardiac triggers were extracted from heart image navigators, and respiratory motion was corrected by rigid registration on each heartbeat. Cine images were reconstructed from the steady‐state portion of 15° readouts using a low‐rank plus sparse reconstruction. The T1 maps were fit using a projection onto convex sets approach from images reconstructed using slice profile–corrected dictionary learning. This strategy was evaluated in a phantom and 14 human subjects.ResultsThe self‐gated signal demonstrated close agreement with the acquired electrocardiogram signal. The image quality for the proposed cine images and standard clinical balanced SSFP images were 4.31 (±0.50) and 4.65 (±0.30), respectively. The slice profile–corrected T1 values were similar to those of the inversion‐recovery spin‐echo technique in phantom, and had a higher global T1 value than that of MOLLI in human subjects.ConclusionsCine and T1 mapping using spiral acquisition with respiratory and cardiac self‐gating successfully acquired T1 maps and cine images in a single acquisition without the need for electrocardiogram gating or breath‐holding. This dual‐excitation flip‐angle approach provides a novel approach for measuring T1 while accounting for and slice profile effect on the apparent .
Internalized weight bias is associated with perceived exertion and affect during exercise in a sample with higher body weight
Authors: Olson KayLoni L. , Goldstein Stephanie P. , Wing Rena R. , Williams David M. , Demos Kathryn E. , Unick Jessica L. 
Published: February 2021

AbstractObjectiveFor individuals with overweight/obesity, internalized weight bias (IWB) is linked to low physical activity (PA). This study used a laboratory‐based paradigm to test the hypothesis that IWB moderates the association between heart rate (HR) and perceived exertion and affect during PA.MethodsParticipants with overweight/obesity completed 30‐min of supervised moderate‐intensity treadmill walking (65%–75% of age‐predicted maximal HR). Body Mass Index (BMI) and Weight Bias Internalization Scale were assessed at baseline. HR was monitored every minute; perceived exertion and affect were assessed every 5 min. Linear mixed models were employed with random effects of time and participant.ResultsThe sample (n = 59; 79.7% female, 91.5% white) had an average BMI = 32.1 kg/m2 (SD: 3.3), and age = 47.1 (SD: 10.3) years. There was a main effect of IWB on perceived exertion (greater IWB was associated with greater perceived exertion during exercise; p < 0.001). There was an interaction of IWB and HR on affect (B = −0.01, p < 0.01). For individuals with high IWB, HR elevations were associated with a negative affective response during exercise. For individuals with low IWB, HR elevations were associated with increased positive affect during PA.ConclusionsFindings indicate that among individuals of higher body weight, IWB is associated with reporting higher perceived exertion during 30 min of moderate intensity PA. IWB moderated the relationship between increasing HR during exercise and affect. Among individuals with overweight/obesity who report IWB, the initial experience of PA may be harder and more unpleasant, with lasting implications for the adoption of PA.
Effects of titanate on the bonding properties of silicone rubber and polyester fabric
Authors: Han Ruijie , Shao Yuanrui , Quan Xudong , Niu Kangmin 
Published: February 2021

AbstractThe effects of titanate on the mechanical properties of silicone rubber and peel strength of polyester fabric with silicone rubber are studied. The tests show that the hardness and mechanical properties of silicone rubber containing 0.2 phr titanate are similar to those of pure silicone rubber, and the peel strength (1.11 N/mm) between fabric and rubber matrix without inner fabric is the highest in the test groups. Fourier transform infrared spectra (FT‐IR) and contact angle test indicate that the surface wettability of silicone rubber is effectively enhanced with the addition of titanate, which is a key factor to improve the bonding properties between silicone rubber and polyester fabric because of the more adequate contact between the adhesive and silicone rubber surface. Due to the difference in the modulus of the fabric along different yarn directions, the peel direction has a significant effect on the peel force between the outer fabric and silicone rubber.
Analyses stratified by maternal age and recombination further characterize genes associated with maternal nondisjunction of chromosome 21
Authors: Chernus Jonathan M. , Sherman Stephanie L. , Feingold Eleanor 
Published: February 2021

AbstractObjectiveIn our previous work, we performed the first genome‐wide association study to find genetic risk factors for maternal nondisjunction of chromosome 21. The objective of the current work was to perform stratified analyses of the same dataset to further elucidate potential mechanisms of genetic risk factors.MethodsWe focused on loci that were statistically significantly associated with maternal nondisjunction based on this same dataset in our previous study and performed stratified association analyses in seven subgroups defined by age and meiotic recombination profile. In each analysis, we contrasted a different subgroup of mothers with the same set of fathers, the mothers serving as cases (phenotype: meiotic nondisjunction of chromosome 21) and the fathers as controls.ResultsOur stratified analyses identified several genes whose patterns of association are consistent with generalized effects across groups, as well as other genes that are consistent with specific effects in certain groups.ConclusionsWhile our results are epidemiological in nature and cannot conclusively prove mechanisms, we identified a number of patterns that are consistent with specific mechanisms. In many cases those mechanisms are strongly supported by available literature on the associated genes.
Microwave‐assisted foaming of polystyrene filled with carbon black; effect of filler content on foamability
Authors: Aghvami‐Panah Mohammad , Jamalpour Seifollah , Ghaffarian S. Reza 
Published: February 2021

AbstractIn this work, polystyrene was filled with carbon black (CB) at 1, 3, and 5 wt% and were foamed via microwave‐assisted (MA) foaming. The composite morphology was tracked by scanning electron microscopy, transmission electron microscopy, and rheology. CB played the dominant role as the selective microwave absorbers to provide the required heat for the cell nucleation and growth. MA foaming is a controllable technique to reach proper foam density and cell size by controlling microwave energy. MA foams microstructurally were compared with the foams created via the conventional foaming procedures, including oil bath heating and fast pressure drop. One advantage of the MA method is increasing the temperature of the bulk and surface of the thick specimen simultaneously. As a result, cell nucleation and growth are uniform throughout the thick composite. Samples with a thickness of 1 cm were foamed via the MA method.
Outcomes of a COVID‐19 recovery program for patients hospitalized with SARS‐CoV‐2 infection in New York City: A prospective cohort study
Authors: Hameed Farah , Palatulan Eugene , Jaywant Abhishek , Said Rami , Lau Corinna , Sood Vandana , Layton Aimee , Gellhorn Alfred 
Published: February 2021

AbstractBackgroundIn the spring of 2020, New York City was an epicenter of coronavirus disease 2019 (COVID‐19). The post‐hospitalization needs of COVID‐19 patients were not understood and no outpatient rehabilitation programs had been described.ObjectiveTo evaluate whether a virtual rehabilitation program would lead to improvements in strength and cardiopulmonary endurance when compared with no intervention in patients discharged home with persistent COVID‐19 symptoms.DesignProspective cohort study.SettingAcademic medical center.PatientsBetween April and July 2020, 106 patients discharged home with persistent COVID‐19 symptoms were treated. Forty‐four patients performed virtual physical therapy (VPT); 25 patients performed home physical therapy (HPT); 17 patients performed independent exercise program (IE); and 20 patients did not perform therapy.InterventionsAll patients were assessed by physiatry. VPT sessions were delivered via secure Health Insurance Portability and Accountability Act compliant telehealth platform 1‐2 times/week. Patients were asked to follow up 2 weeks after initial evaluation.Main Outcome MeasuresPrimary study outcome measures were the change in lower body strength, measured by the 30‐second sit‐to‐stand test; and the change in cardiopulmonary endurance, measured by the 2‐minute step test.ResultsAt the time of follow‐up, 65% of patients in the VPT group and 88% of patients in the HPT group met the clinically meaningful difference for improvement in sit‐to‐stand scores, compared with 50% and 17% of those in the IE group and no‐exercise group (P = .056). The clinically meaningful difference for improvement in the step test was met by 74% of patients in the VPT group and 50% of patients in the HPT, IE, and no‐exercise groups (P = .12).ConclusionsVirtual outpatient rehabilitation for patients recovering from COVID‐19 improved lower limb strength and cardiopulmonary endurance, and an HPT program improved lower limb strength. Virtual rehabilitation seems to be an efficacious method of treatment delivery for recovering COVID‐19 patients.
Phospho‐dependent signaling during the general stress response by the atypical response regulator and ClpXP adaptor RssB
Authors: Schwartz Jacob , Son Jonghyeon , Brugger Christiane , Deaconescu Alexandra M. 
Published: February 2021

AbstractIn the model organism Escherichia coli and related species, the general stress response relies on tight regulation of the intracellular levels of the promoter specificity subunit RpoS. RpoS turnover is exclusively dependent on RssB, a two‐domain response regulator that functions as an adaptor that delivers RpoS to ClpXP for proteolysis. Here, we report crystal structures of the receiver domain of RssB both in its unphosphorylated form and bound to the phosphomimic BeF3−. Surprisingly, we find only modest differences between these two structures, suggesting that truncating RssB may partially activate the receiver domain to a “meta‐active” state. Our structural and sequence analysis points to RssB proteins not conforming to either the Y–T coupling scheme for signaling seen in prototypical response regulators, such as CheY, or to the signaling model of the less understood FATGUY proteins.
A novel microsurgery robot mechanism with mechanical motion scalability for intraocular and reconstructive surgery
Authors: Yang Un‐Je , Kim Duksang , Hwang Minho , Kong Dukyoo , Kim JoonHwan , Nho Young‐Hoon , Lee WonKi , Kwon Dong‐Soo 
Published: February 2021

AbstractBackgroundIntraocular surgery and reconstructive surgery are challenging microsurgery procedures that require two types of motion: precise motion and larger motion. To effectively perform the requisite motion using a robot, it is necessary to develop a manipulator that can adjust the scale of motion between precise motion and less precise, yet larger motion.AimsIn this paper, we propose a novel microsurgery robot using the dual delta structure (DDS) to mechanically scale the motion to seamlessly adjust between precise and larger motion.Materials & MethodsThe DDS forms a lever mechanism that enables the motion scaling at the end‐effector using two delta platforms. Seamless scale adjustment enables the robot to effectively perform various surgical moves.ResultsA prototype robot system was developed to validate the effectiveness of the DDS. The experiment results in various scale settings validated the scaling mechanism of the DDS.ConclusionThrough a graphical simulation and measurement experiment, the robot's precision level and attainable workspace has been confirmed adequate for intraocular and reconstructive surgery.
Cu2ZnSnS4, a Fascinating Counter Electrode for TiO2‐Free Dye‐Sensitized Solar Cells
Authors: Roy Anurag , Sundaram Senthilarasu , Mallick Tapas K. 
Published: February 2021

AbstractSince innovation, different dye‐sensitized solar cells (DSSCs) have endeavored with additional components to escalate the efficiency, cost‐effectiveness and long‐term stability. Various approaches have been executed to reduce the amount of costly platinum (Pt) used in DSSCs and/or to explore cheaper alternatives to Pt. In this work, cheaper elements based quaternary chalcogenide alloy; Cu2ZnSnS4 (CZTS) has been projected as a prominent counter electrode (CE) candidate to Pt in DSSCs. The CZTS thin film has been developed by an in‐situ synthesis employing a hydrothermal technique and further evaluating various physicochemical characterization. Our results manifest that using the CZTS CE, a power conversion efficiency (PCE) of 4.3 % was exhibited for TiO2 based photoanode. The highest PCE of 6.5 % was achieved for BaSnO3 based photoanode, a promising alternative oxide to TiO2 photoanode. This work further signifies a unique combination of newly developed BaSnO3(BSO)‐CZTS DSSCs, could be a promising competitor to TiO2‐Pt DSSCs.