bluuebunny/crossref_metadata_2025 huggingface dataset:
Regorafenib Efficacy After Sorafenib in Patients With Recurrent Hepatocellular Carcinoma After Liver Transplantation: A Retrospective Study
Authors: Iavarone Massimo , Invernizzi Federica , Ivanics Tommy , Mazza Stefano , Zavaglia Claudio , Sanduzzi‐Zamparelli Marco , Fraile‐López Miguel , Czauderna Carolin , Di Costanzo Giovanni , Bhoori Sherrie , Pinter Matthias , Manini Matteo Angelo , Amaddeo Giuliana , Yunquera Ainhoa Fernandez , Piñero Federico , Blanco Rodríguez Maria Jose , Anders Margarita , Aballay Soteras Gabriel , Villadsen Gerda Elisabeth , Yoon Peter Daechul , Cesarini Lucia , Díaz‐González Álvaro , González‐Diéguez Maria Luisa , Tortora Raffaella , Weinmann Arndt , Mazzaferro Vincenzo , Romero Cristóbal Mario , Crespo Gonzalo , Regnault Helene , De Giorgio Massimo , Varela Maria , Prince Rebecca , Scudeller Luigia , Donato Maria Francesca , Wörns Marcus‐Alexander , Bruix Jordi , Sapisochin Gonzalo , Lampertico Pietro , Reig Maria
Published: August 2021

Safety of regorafenib in hepatocellular carcinoma (HCC) recurrence after liver transplantation (LT) has been recently demonstrated. We aimed to assess the survival benefit of regorafenib compared with best supportive care (BSC) in LT patients after sorafenib discontinuation. This observational multicenter retrospective study included LT patients with HCC recurrence who discontinued first‐line sorafenib. Group 1 comprised regorafenib‐treated patients, whereas the control group was selected among patients treated with BSC due to unavailability of second‐line options at the time of sorafenib discontinuation and who were sorafenib‐tolerant progressors (group 2). Primary endpoint was overall survival (OS) of group 1 compared with group 2. Secondary endpoints were safety and OS of sequential treatment with sorafenib + regorafenib/BSC. Among 132 LT patients who discontinued sorafenib included in the study, 81 were sorafenib tolerant: 36 received regorafenib (group 1) and 45 (group 2) received BSC. Overall, 24 (67%) patients died in group 1 and 40 (89%) in group 2: the median OS was significantly longer in group 1 than in group 2 (13.1 versus 5.5 months; P < 0.01). Regorafenib treatment was an independent predictor of reduced mortality (hazard ratio, 0.37; 95% confidence interval [CI], 0.16‐0.89; P = 0.02). Median treatment duration with regorafenib was 7.0 (95% CI, 5.5‐8.5) months; regorafenib dose was reduced in 22 (61%) patients for adverse events and discontinued for tumor progression in 93% (n = 28). The median OS calculated from sorafenib start was 28.8 months (95% CI, 17.6‐40.1) in group 1 versus 15.3 months (95% CI, 8.8‐21.7) in group 2 (P < 0.01). Regorafenib is an effective second‐line treatment after sorafenib in patients with HCC recurrence after LT.
Delayed Senescence of Human Vascular Endothelial Cells by Molecular Mobility of Supramolecular Biointerfaces
Authors: Arisaka Yoshinori , Masuda Hiroki , Yoda Tetsuya , Yui Nobuhiko
Published: August 2021

Yes‐associated protein (YAP), a transcriptional coactivator of the Hippo signaling pathway, has been widely implicated in vascular aging and diseases. For preventing vascular endothelial cell senescence, the design and development of biomaterials to regulate YAP activity are required. This study prepares polyrotaxane‐coated surfaces with molecular mobility and clarifies the role of the mobility on vascular endothelial cell senescence through Hippo‐YAP signaling. The polyrotaxane surface with high mobility induces cytoplasmic YAP localization in endothelial cells, whereas the surface with low mobility induces nuclear YAP localization. After serial cultivation of endothelial cells using polyrotaxane surfaces with different mobilities for 35 d, the endothelial cells aged on the polyrotaxane surface with high mobility exhibit higher proliferative potential, smaller spreading size, and lower activity of senescence‐associated β‐galactosidase than those aged on the surface with low mobility. These findings suggest that cellular senescence can be delayed by modulating the molecular mobility on polyrotaxane surfaces.
Assessment of Mechanical and Electrical Performances of Polylactic Acid/Liquid Natural Rubber/Graphene Platelets Nanocomposites in the Light of Different Graphene Platelets Functionalization Routes
Authors: Mohd Amran Nurul Aishah , Ahmad Sahrim , Chen Ruey Shan , Shahdan Dalila , Flaifel Moayad Husien , Omar Afiqah
Published: August 2021

The essence core of this study is to investigate the effect of functionalization of graphene platelets (GNPs) and its low loadings of 0.25, 0.50, 0.75, and 1.00 wt% on the chemical, mechanical, and electrical properties of polylactic acid/liquid natural rubber (PLA/LNR) blend prepared by melt blending method. GNPs are treated with amino dodecanoic acid via covalent interaction and Triton X‐100 (TX100) via non‐covalent interaction to produce ADA‐functionalized GNPs (GNP‐A) and TX100‐functionalized GNPs (GNP‐T), respectively. At 0.75 wt% GNPs, the PLA/LNR nanocomposites exhibit the highest tensile strength of 24.38, 35.70, 45.47 MPa for untreated GNPs (GNP‐u), GNP‐T, and GNP‐A, respectively. Variable pressure scanning electron microscopy proves better interaction of treated‐GNPs with the matrix, while transmission electron microscopy micrographs have shown that PLA/LNR/GNP‐A has the best filler dispersion with minimal stacking and agglomeration found. A remarkable improvement of electrical properties is observed for treated‐GNPs nanocomposite with lower percolation threshold value of 0.3 wt% as compared to that of GNP‐u nanocomposite (0.4 wt%).
Mechano‐Optical Response of Novel Polymer Composites Based on Elastic Polyurethane Matrix Filled with Low‐Molar‐Mass Cholesteric Droplets
Authors: Balenko Nikolai V. , Shibaev Valery P. , Bobrovsky Alexey Yu.
Published: August 2021

Among the various types of liquid crystalline (LC) structures, the cholesteric mesophase attracts special attention in view of helical supramolecular structure determining their specific optical properties. The helix pitch of cholesteric liquid crystals is very sensitive to mechanical stress, resulting in change of their optical properties and position of selective light reflection peak. Here, films of polymer‐dispersed cholesteric liquid crystals based on polyurethane elastomer are prepared and studied. Liquid crystal mixtures based on chiral cholesterol derivatives are uniformly dispersed in the form of micrometer‐sized droplets in an elastomeric matrix. A significant mechano‐optical response of the composites under the action of deformation is demonstrated, and the change in the position of the selective light reflection band during mechanical stress is studied in detail. A shift in the selective light reflection peak by 100 nm or more is found. This process is accompanied by color transformations of brightly colored films. Such materials can be promising for creating stress and deformation sensors, ripple and bending sensors, and other technical devices.
A High Strength Hydrogel with a Core–Shell Structure Simultaneously Serving as Strain Sensor and Solar Water Evaporator
Authors: Peng Yinjie , Tang Shiqing , Wang Xiaoyu , Ran Rong
Published: August 2021

A super‐strong poly (acrylic acid)‐ poly(3,4‐ethylene dioxythiophene) (PAA‐PEDOT) hydrogel with a unique core‐shell structure is successfully constructed and studied. The shell composed of the conductive polymer PEDOT makes the composite hydrogel possess mechanical strength, electrical conductivity, and photothermal conversion properties, while the PAA hydrogel core ensures the flexibility, recovery, and water absorption of the composite hydrogel. The prepared PAA‐PEDOT hydrogel displays outstanding tensile strength (up to 780 KPa) and satisfactory conductivity (6.6 S m−1). Notably, the flexible strain sensor made of PAA‐PEDOT composite hydrogel presents both high sensitivity (gauge factor up to 8.87) and short response time (<200 ms), demonstrating that the composite hydrogel can accurately and timely detect the movement of human joints. In addition, PAA‐PEDOT composite hydrogel also has excellent photothermal conversion properties and can be used as a highly efficient solar water evaporator, which has a water evaporation efficiency of up to 3.05 kg m−2 h and an excellent photothermal conversion efficiency of 95% under 1‐sun irradiation (1kW m−2). These features make the composite hydrogel has great potential in many fields such as motion sensing, seawater desalination, and wastewater treatment.
Spray Coating of 2‐ and 3‐D Solid Substrates Using a Sulfated Polysaccharide for Marine Antifouling Applications
Authors: Jeong Yeonwoo , Cho Woo Kyung , Kang Sung Min
Published: August 2021

Marine antifouling coating using functional polymers has emerged as an important tool to combat marine fouling. Owing to their natural abundance, polysaccharides represent a more sustainable option than synthetic polymers and carrageenan, a sulfated polysaccharide, is identified as a promising candidate for further research based on its excellent marine antifouling properties. However, existing research has only explored the application of carrageenan‐based coatings for 2D objects, using techniques such as spin‐coating. Here, a spray‐coating method is proposed to apply carrageenan‐based coatings to the surfaces of 2‐ and 3‐D objects. The coated surfaces exhibit high stability under various chemical/physical stresses and high resistance to protein adsorption and marine diatom adhesion.
Firearm responses by MH patients could support suicide prevention efforts
Authors: Canady Valerie A.
Published: August 2021

Patients receiving care for mental health when asked to complete a questionnaire that included whether they had access to guns could provide critical information to supporting suicide prevention efforts, according to new research in JAMA Health Forum. The Kaiser Permanente study was funded by its Office of Community Health as part of its Firearm Injury Prevention Program.
Staffing struggles in New Hampshire slow progress of mobile crisis care
Authors: Enos Gary
Published: August 2021

The mental health provider community is by no means immune to the workforce shortages that have been plaguing many U.S. industries. Provider organizations and advocates in New Hampshire are trying to remain optimistic in the face of hiring challenges that have slowed full implementation of mobile crisis care teams across the state.
Abdominal perforator exchange flap (APEX): A classification of pedicle rearrangements
Authors: Zoccali Giovanni , Farhadi Jian
Published: August 2021

Introduction

Abdominal‐based reconstruction is the most commonly performed method for breast reconstruction after mastectomy using the patient's own tissues. DIEP flap has allowed to reduce the donor site morbidity but the incidence of bulging or hernia remains still high, especially when flap is based on multiple perforators. Abdominal Perforator Exchange flap (APEX) represents a further step forward in preserving the abdominal wall structures by disassembling the pedicle components and their reconstitution at the end of the dissection. In this study, we explore the possible anatomical configurations of perforators exchange for APEX, providing a simple classification of perforators reconstitution patterns and the possible clinical implications.

Materials and methods

A retrospective study was conducted on patients who received APEX flap for abdominal based breast reconstruction. Preoperative CT scans and procedure descriptions were analyzed to identify the vascular patterns during flap harvesting and the pedicle reconstitution sites. The onset of abdominal wall and flap related complications were investigated.

Results

APEX flap was performed on 51 women and four vascular patterns were identified. We identified the Type A pattern in 36 cases (70.6%), the Type B pattern in 8 (15.7%), and the Type C pattern in 5 (9.8%). We performed an extra‐anatomical reanastomosis (Type D) in only two case (3.9%) (p = .09). We recorded anastomotic problems in five pedicles' reconstitution and the odds ratio showed a possible correlation between the localization of pedicle division and the anastomosis problems (p > .05). No total or partial flap loss was recorded during this study. Marginal fat necrosis was clinically observed in three cases, which had very large flaps. No bulging or hernia was recorded.

Conclusion

Our perforators exchange classification for abdominal‐based flap helps clinician in planning the surgery and also in describing the procedure easily allowing a more efficient communication. This classification could be used to approach perforator flaps with multiple vessels at other anatomical locations as well.
Deep learning‐based reconstruction of interventional tools and devices from four X‐ray projections for tomographic interventional guidance
Authors: Eulig Elias , Maier Joscha , Knaup Michael , Bennett N. Robert , Hörndler Klaus , Wang Adam S. , Kachelrieß Marc
Published: August 2021

Purpose

Image guidance for minimally invasive interventions is usually performed by acquiring fluoroscopic images using a monoplanar or a biplanar C‐arm system. However, the projective data provide only limited information about the spatial structure and position of interventional tools and devices such as stents, guide wires, or coils. In this work, we propose a deep learning‐based pipeline for real‐time tomographic (four‐dimensional [4D]) interventional guidance at conventional dose levels.

Methods

Our pipeline is comprised of two steps. In the first one, interventional tools are extracted from four cone‐beam CT projections using a deep convolutional neural network. These projections are then Feldkamp reconstructed and fed into a second network, which is trained to segment the interventional tools and devices in this highly undersampled reconstruction. Both networks are trained using simulated CT data and evaluated on both simulated data and C‐arm cone‐beam CT measurements of stents, coils, and guide wires.

Results

The pipeline is capable of reconstructing interventional tools from only four X‐ray projections without the need for a patient prior. At an isotropic voxel size of 100 , our methods achieve a precision/recall within a 100 environment of the ground truth of 93%/98%, 90%/71%, and 93%/76% for guide wires, stents, and coils, respectively.

Conclusions

A deep learning‐based approach for 4D interventional guidance is able to overcome the drawbacks of today's interventional guidance by providing full spatiotemporal (4D) information about the interventional tools at dose levels comparable to conventional fluoroscopy.
Low‐dose CT denoising via convolutional neural network with an observer loss function
Authors: Han Minah , Shim Hyunjung , Baek Jongduk
Published: August 2021

Purpose: Convolutional neural network (CNN)‐based denoising is an effective method for reducing complex computed tomography (CT) noise. However, the image blur induced by denoising processes is a major concern. The main source of image blur is the pixel‐level loss (e.g., mean squared error [MSE] and mean absolute error [MAE]) used to train a CNN denoiser. To reduce the image blur, feature‐level loss is utilized to train a CNN denoiser. A CNN denoiser trained using visual geometry group (VGG) loss can preserve the small structures, edges, and texture of the image.However, VGG loss, derived from an ImageNet‐pretrained image classifier, is not optimal for training a CNN denoiser for CT images. ImageNet contains natural RGB images, so the features extracted by the ImageNet‐pretrained model cannot represent the characteristics of CT images that are highly correlated with diagnosis. Furthermore, a CNN denoiser trained with VGG loss causes bias in CT number. Therefore, we propose to use a binary classification network trained using CT images as a feature extractor and newly define the feature‐level loss as observer loss.

Methods: As obtaining labeled CT images for training classification network is difficult, we create labels by inserting simulated lesions. We conduct two separate classification tasks, signal‐known‐exactly (SKE) and signal‐known‐statistically (SKS), and define the corresponding feature‐level losses as SKE loss and SKS loss, respectively. We use SKE loss and SKS loss to train CNN denoiser.

Results: Compared to pixel‐level losses, a CNN denoiser trained using observer loss (i.e., SKE loss and SKS loss) is effective in preserving structure, edge, and texture. Observer loss also resolves the bias in CT number, which is a problem of VGG loss. Comparing observer losses using SKE and SKS tasks, SKS yields images having a more similar noise structure to reference images.

Conclusions: Using observer loss for training CNN denoiser is effective to preserve structure, edge, and texture in denoised images and prevent the CT number bias. In particular, when using SKS loss, denoised images having a similar noise structure to reference images are generated.
Estimation of imaging intervals and intrafraction displacement in CyberKnife image‐guided radiotherapy for intracranial lesions
Authors: Inata Hiroki , Tominaga Masahide , Sasaki Motoharu , Kuribayashi Yuta , Sodeoka Noritaka , Katakami Azusa , Nishizaki Osamu
Published: August 2021

Purpose

A recent report by the American Association of Physicists in Medicine Task Group 75 and 180 provided imaging dose estimates for image‐guided CyberKnife radiotherapy. However, to our knowledge, there have been no concrete demonstrations of imaging intervals that are directly linked to exposure dose. We hypothesized that setting a rational standard may be clearer through a balance of treatment accuracy and reducing imaging doses if the margin of the planned treatment volume is controlled through the imaging interval. This study was conducted to simulate the association between the imaging interval and intrafraction displacement and to estimate a reasonable internal margin (IM).

Methods

We retrospectively analyzed data from 21 shell‐fixed heads of patients treated with CyberKnife G3 using our dedicated monitoring system. This system comprises pressure sensors that can monitor head displacement every 0.2 s in the absence of any imaging dose. First, the root sum square of head displacements was calculated in 76 treatment fractions with an imaging interval of 10–1440 s. The cumulative frequency of a root sum square displacement (which was less than the IM) was evaluated in image verifications that were undertaken 546 274 times for every imaging interval.

Results

We found that the mean values and SDs of the displacement were larger in proportion to the imaging interval (p < 0.002) and that the maximum displacements did not correlate in any combination within 720 s (p > 0.056). The cumulative frequencies of displacement of 0.6 and 1.4 mm (i.e., less than an IM) were 99.2% and 99.1% for imaging intervals of 10 and 360 s, respectively.

Conclusions

In the current study, we found that imaging intervals were directly proportional to intrafraction displacement and that there was no correlation in any combination within 720 s. Imaging intervals for an IM of 0.6 and 1.4 mm were 10 and 360 s, respectively, with a 99% confidence interval of intrafraction displacement. With CyberKnife M6 or a previous version of this system, the imaging dose could be reduced by 0.4760 mSv per 24‐min treatment as the imaging dose ranged from 0.4896 to 0.0136 mSv for imaging intervals of 10 and 360 s with an IM of 0.6 and 1.4 mm, respectively. A rational method that includes X‐ray imaging guidance may be achieved with modulation of the imaging interval via the CyberKnife system.
Cardiovascular reactivity as a measure of irritability in a transdiagnostic sample of youth: Preliminary associations
Authors: Naim Reut , Goodwin Matthew S. , Dombek Kelly , Revzina Olga , Agorsor Courtney , Lee Kyunghun , Zapp Christian , Freitag Gabrielle F. , Haller Simone P. , Cardinale Elise , Jangraw David , Brotman Melissa A.
Published: August 2021

Objectives

Irritability is a transdiagnostic symptom in developmental psychopathology, conceptualized as a low threshold for frustration and increased proneness to anger. While central to emotion regulation, there is a vital need for empirical studies to explore the relationship between irritability and underlying physiological mechanisms of cardiovascular arousal.

Methods

We examined the relationship between irritability and cardiovascular arousal (i.e., heart rate [HR] and heart rate variability [HRV]) in a transdiagnostic sample of 51 youth (M = 12.63 years, SD = 2.25; 62.7% male). Data was collected using the Empatica E4 during a laboratory stop‐signal task. In addition, the impact of motion activity, age, medication, and sleep on cardiovascular responses was explored.

Results

Main findings showed that irritability was associated with increased HR and decreased HRV during task performance.

Conclusions

Findings support the role of peripheral physiological dysregulation in youth with emotion regulation problems and suggest the potential use of available wearable consumer electronics as an objective measure of irritability and physiological arousal in a transdiagnostic sample of youth.
Block low‐rank single precision coarse grid solvers for extreme scale multigrid methods
Authors: Buttari Alfredo , Huber Markus , Leleux Philippe , Mary Theo , Rüde Ulrich , Wohlmuth Barbara
Published: August 2021

Extreme scale simulation requires fast and scalable algorithms, such as multigrid methods. To achieve asymptotically optimal complexity, it is essential to employ a hierarchy of grids. The cost to solve the coarsest grid system can often be neglected in sequential computings, but cannot be ignored in massively parallel executions. In this case, the coarsest grid can be large and its efficient solution becomes a challenging task. We propose solving the coarse grid system using modern, approximate sparse direct methods and investigate the expected gains compared with traditional iterative methods. Since the coarse grid system only requires an approximate solution, we show that we can leverage block low‐rank techniques, combined with the use of single precision arithmetic, to significantly reduce the computational requirements of the direct solver. In the case of extreme scale computing, the coarse grid system is too large for a sequential solution, but too small to permit massively parallel efficiency. We show that the agglomeration of the coarse grid system to a subset of processors is necessary for the sparse direct solver to achieve performance. We demonstrate the efficiency of the proposed method on a Stokes‐type saddle point system solved with a monolithic Uzawa multigrid method. In particular, we show that the use of an approximate sparse direct solver for the coarse grid system can outperform that of a preconditioned minimal residual iterative method. This is demonstrated for the multigrid solution of systems of order up to degrees of freedom on a petascale supercomputer using 43,200 processes.
An online survey to assess parents' preferences for learning about child health research
Authors: Knisley Lisa , Le Anne , Scott Shannon D. ,   the KidsCAN PERC Innovative Pediatric Clinical Trials initiative
Published: August 2021

Aim

Ethical and logistical issues often exacerbate recruitment problems in child health studies. This study aims: (a) to provide new knowledge on how parents want to hear about child health research and (b) to inform the KidsCAN PERC iPCT initiative's re‐examination of recruitment and retention strategies for pediatric emergency department research studies.

Design

We employed a cross‐sectional, survey design.

Methods

An online survey was distributed to participants (i.e., parents) through partner organizations' advisory group mailing lists. Frequencies and measures of central tendency guided data analysis.

Results

Parents are interested in hearing about child health research opportunities, particularly during general practitioner, pediatrician or walk‐in clinic visits. Most parents wanted updates on the research team, progress and results and support to participate, such as reimbursement of travel and childcare costs. Results can inform research teams in the planning of communications to effectively share research opportunities, progress and results with parents.
Molecular features of non‐anaplastic peripheral T‐cell lymphoma in children and adolescents
Authors: Au‐Yeung Rex K. H. , Richter Julia , Iaccarino Ingram , Abramov Dmitriy , Bacon Chris M. , Balagué Olga , d'Amore Emanuele S. G. , Simonitsch‐Klupp Ingrid , Hebeda Konnie , Nakazawa Atsuko , Oschlies Ilske , Kontny Udo , Woessmann Wilhelm , Burkhardt Birgit , Klapper Wolfram
Published: August 2021

Non‐anaplasticperipheral T‐cell lymphomas (PTCL) are rare tumors in children, adolescents, and young adults (CAYA) with poor prognosis and scarce genetic data. We analyzed lymphoma tissue from 36 patients up to 18 years old with PTCL, not otherwise specified (PTCL‐NOS), hepatosplenic T‐cell lymphoma, Epstein–Barr virus (EBV)‐positive T‐lymphoproliferative diseases, subcutaneous panniculitis‐like T‐cell lymphoma, and other PTCL types. Twenty‐three patients (64%) had at least one genetic variant detectable, including TET2, KMT2C, PIK3D, and DMNT3A. TP53 and RHOA variants, commonly found in adults, were not identified. Eight of 20 (40%) CAYA PTCL‐NOS had no detectable mutations. The genetic findings suggest that CAYA PTCL differ from adult cases.
Polymer melt rheology: Advantages of frequency sweeps using randomly selected frequencies*
Authors: Shaw Montgomery T.
Published: August 2021

Measurement of the viscoelastic properties of polymer solids, melts, and solutions is broadly practiced. The so‐called “frequency sweep” appears in thousands of publications, with data covering up to five decades of frequency to reveal, for example, the relative molecular size of a polymer. To perform these experiments, the frequency range is typically “swept” from high to low frequency or vice versa. Unfortunately, this confounds frequency with run time. This is more than annoying; time effects can result in serious mistakes in the interpretation of the data. Fortunately, the confounding can be eliminated by simply running the frequencies in random order, which converts the time trend to random error. Described here is how this can be done and shows via modeling that the result can not only show that time effects are present but can be analyzed to show the time rate of change of the sample. This analysis is demonstrated using two real examples: loss of solvent from poly(dimethyl siloxane) gum and gelation of porcine gelatin. This method compares well with the multiwave technique, but does not require any special software or adjustments of amplitude with frequency or harmonic spacing of the frequencies.
Expanding notions of equity: Body diversity and social justice
Authors: Campbell Stephanie McCullough
Published: August 2021

Despite their negative effects on the emotional, physical, and social wellbeing of students, weight stigma and anti‐fat attitudes are rarely systematically addressed in schools or within school psychology. Weight‐based oppression is regarded differently than other domains of prejudice. Therefore, implicit and explicit bias continue unimpeded, even when practitioners are attentive to other areas of social injustice. Mental health providers serving schools must acknowledge the prevalence of weight stigma and fatphobia to reduce their deleterious and oppressive effects. This conceptual paper outlines the underpinnings of weight stigma, overviews the necessity of addressing it and body image in educational settings, incorporates interdisciplinary perspectives, and proposes a justice‐oriented shift in the conceptualization of weight status within school psychological service delivery.
Identification of key stabilizing interactions of amyloid‐β oligomers based on fragment molecular orbital calculations on macrocyclic β‐hairpin peptides
Authors: Firouzi Rohoullah , Noohi Bahare
Published: August 2021

Analyzing the electronic states and inter‐/intra‐molecular interactions of amyloid oligomers expand our understanding of the molecular basis of Alzheimer's disease and other amyloid diseases. In the current study, several high‐resolution crystal structures of oligomeric assemblies of Aβ‐derived peptides have been studied by the ab initio fragment molecular orbital (FMO) method. The FMO method provides comprehensive details of the molecular interactions between the residues of the amyloid oligomers at the quantum mechanical level. Based on the calculations, two sequential aromatic residues (F19 and F20) and negatively charged E22 on the central region of Aβ have been identified as key residues in oligomer stabilization and potential interesting pharmacophores for preventing oligomer formation.
You have safety instrumented system bypassed right now and don't know it
Authors: Marszal Edward M.
Published: August 2021

Safety instrumented systems (SIS), also known as emergency shutdowns, interlocks, and trips, are very common and critical safeguards protecting process plants. In order to maintain and test these systems, they are usually implemented with well‐engineered and controlled bypasses, typically including alarm logging, bypass authorization, and auditing. Even so, there are myriad ways to place an SIS component into bypass, sometimes without even realizing it. Many of these methods occur in the field, away from the watchful eye of the board operator. In many cases, the bypasses occur inadvertently during maintenance or operational activities and are left in place, unmanaged. Common culprits include solenoid valve latches, shutoff valve handwheels, and hand‐off‐auto switches on pump and compressors. This paper will explain how some equipment can be inadvertently put into bypass and methods for documenting and verifying that they are not in bypass using advanced mobile computing assisted car‐seal management.
Pandemic risk management; protecting people while ensuring business continuity
Authors: Sneddon James
Published: August 2021

The COVID‐19 pandemic swept across the globe in the latter half of 2019, throughout 2020 and into 2021. In response, many organizations implemented work from home policies, while others stopped operations entirely in an effort to limit the spread throughout their workforce and supporting communities. This containment strategy was not universally viable; long‐term shutdowns impacted the economic viability of companies, and some industries were designated as an “essential service” and thus continued operations. These employers faced the proposition of balancing the needs of the business and the community with a continued responsibility to provide a safe workplace for employees. This paper demonstrates how the application of common risk management methodologies, such as bowtie analysis combined with an appropriate assurance and verification process (e.g., the lines of defense model), can help the risks associated with a resumption or continuation of in‐person operations in a pandemic to be better understood and ensure the measures in place to manage said risk are appropriate and effective.
Recurvature and movement processes of tropical cyclones over the Bay of Bengal
Authors: Akter Nasreen , Tsuboki Kazuhisa
Published: August 2021

Active bimodal tropical cyclones (TCs) are embedded in nonuniform flows over the Bay of Bengal (BoB). More than half of the TCs that occurred from 1990 to 2019 recurved from their original path due to the influence of 500–300 hPa steering flows. Premonsoon TCs have a tendency to turn right and make landfall on the right‐side coastal areas of the BoB. On the other hand, most of the TCs that occurred in the postmonsoon season crossed the left coast or east coast of India, despite being left or right from their path. The simulation shows that Cyclone Roanu (2016) was driven by a warm, moist, unstable southwesterly that was blocked and diverted by the hot, dry stable air masses of northerlies and northwesterlies. As a result, the TC moved along the dry–moist boundary, keeping a constant distance of ∼400 km between the eye and dryline. Conversely, the combined steering of moist southeasterly and southward‐moving upper‐level westerly jets controlled the track of postmonsoon Cyclone Madi (2013), encompassing a left turn of ∼150°. In addition to the primary steering mechanism, TC vortex propagation can be explained by the strong vertical shear (>30 m·s−1) offered by the dryline during the premonsoon period and near the monsoon trough in the postmonsoon period. This vertical shear causes the upper‐level anticyclone to tilt downshear, resulting in the forward motion of the TC vortex. The deep convection and associated mesovortices, especially those that are more prominent along the dryline, additionally influence asymmetric diabatic heating, contributing to the advection of TC potential vorticity.
Novel controller design for fault tolerant tracking with general additive faults and disturbances
Authors: Stefanovski Jovan D.
Published: August 2021

A formulation of the problem of fault tolerant tracking (FTT) in presence of general additive faults and disturbances is given. It is proved that a necessary condition for the FTT problem is that the plant is minimum‐phase. Then the problem is solved for the minimum‐phase descriptor systems, but possibly with zeros at infinity. The proposed overall controller consists of a feedback controller, which is stabilizing, and a feedforward controller, whose role is to achieve the tracking of an arbitrary reference signal by the controlled output. The feedback controller consists of a possibly unstable, improper and non‐minimum‐phase nominal controller, a fault estimator, and a fault compensator. The role of the nominal controller is to achieve a nominal tracking behavior in absence of faults. The role of the fault compensator is to achieve a nominal tracking behavior in presence of faults, in case that the fault estimation is accurate. However, the fault estimation need not to be accurate, if a design parameter, depending on the nominal controller, can be chosen small. Illustrative examples are given.
The Challenge of Cultivating National and Cosmopolitan Identities Through Literature: Insights From Singapore Schools
Authors: Choo Suzanne S. , Chua Bee Leng , Yeo Dennis
Published: August 2021

Since the late 20th century, scholars have called for a need to broaden the aims of teaching English Literature away from its Eurocentric focus. Much effort has also been invested in making the subject more relevant through diversifying the texts studied and connecting texts to current social and global issues. It is pertinent now to ask what the significant role of Literature is in a globally interconnected age. In particular, what do teachers believe are key philosophical objectives of teaching literature, and how does this influence the texts they select, the instructional strategies they employ, and the values they seek to cultivate in the classroom? In this article, we report on the first National Survey of Literature Teachers’ Beliefs and Practices in Singapore schools. First, we review four key pedagogical movements that have underpinned the teaching of literature in schools around the world: New Criticism, Reader‐Response Criticism, Poststructuralist Criticism, and Ethical Criticism. These respectively represent four key constructs (text, reader, culture, and other) used in the design and analysis of our survey instrument. Next, we report on the survey findings, focusing on Singapore as a barometer of current trends given its identity as an Anglophone country negotiating conflicting global and postcolonial identities with an education system that inhabits colonial traditions. We highlight key tensions arising from the impetus to develop national and cosmopolitan identities through Literature, and reflect on the implications for future directions in teaching.
“If We Don't Have Diversity, There's No Future to See”: High‐school students' perceptions of race and gender representation in STEM
Authors: Martin Anne E. , Fisher‐Ari Teresa R.
Published: August 2021

The perceptions of students interested in STEM, particularly those too often excluded due to race and/or gender, are necessary to create educational experiences that additively contribute to students' access and inclusion in STEM. The purpose of this inquiry was to understand the perceptions of 34 high‐school students about race and gender representation in STEM. Students participated in a 3‐week, university‐sponsored summer programme geared toward teaching and science, technology, engineering, and mathematics (STEM). At the end of the programme, we interviewed students about STEM in their community, STEM role models, potentially working in a STEM field, barriers to STEM, and why they think White men are disproportionately represented in STEM fields. Guided by a critical framework with an intersectional lens, qualitative content analysis of interview data centered on the descriptive codes “race” and “gender” using a constant comparative analytic approach. Results indicated that participants (1) drew on family role models in STEM, (2) used White privilege and patriarchy at varying levels to explain exclusion from STEM, (3) described limited, stereotypical, and hidden depictions of race and gender in STEM, and (4) often perceived STEM as "pushed" while not explicitly associating STEM with helping, or giving back to their community. Implications drawn from participant perspectives call for educational endeavors that expand dominant conceptions of who and what is considered STEM, center students' families and communities, utilize a problem‐based approach positioning STEM as a tool for social justice, and include direct conversations about gendered racism and stereotypes.
Allogeneic Mesenchymal Stromal Cells for Cartilage Regeneration: A Review of in Vitro Evaluation, Clinical Experience, and Translational Opportunities
Authors: Aldrich Ellison D. , Cui Xiaolin , Murphy Caroline A. , Lim Khoon S. , Hooper Gary J. , McIlwraith C. Wayne , Woodfield Tim B.F.
Published: August 2021

The paracrine signaling, immunogenic properties and possible applications of mesenchymal stromal cells (MSCs) for cartilage tissue engineering and regenerative medicine therapies have been investigated through numerous in vitro, animal model and clinical studies. The emerging knowledge largely supports the concept of MSCs as signaling and modulatory cells, exerting their influence through trophic and immune mediation rather than as a cell replacement therapy. The virtues of allogeneic cells as a ready-to-use product with well-defined characteristics of cell surface marker expression, proliferative ability, and differentiation capacity are well established. With clinical applications in mind, a greater focus on allogeneic cell sources is evident, and this review summarizes the latest published and upcoming clinical trials focused on cartilage regeneration adopting allogeneic and autologous cell sources. Moreover, we review the current understanding of immune modulatory mechanisms and the role of trophic factors in articular chondrocyte-MSC interactions that offer feasible targets for evaluating MSC activity in vivo within the intra-articular environment. Furthermore, bringing labeling and tracking techniques to the clinical setting, while inherently challenging, will be extremely informative as clinicians and researchers seek to bolster the case for the safety and efficacy of allogeneic MSCs. We therefore review multiple promising approaches for cell tracking and labeling, including both chimerism studies and imaging-based techniques, that have been widely explored in vitro and in animal models. Understanding the distribution and persistence of transplanted MSCs is necessary to fully realize their potential in cartilage regeneration techniques and tissue engineering applications.
Effect of chain length on the anticorrosion property of bis[3‐(triethoxysilyl)propyl]tetrasulfide/trimethoxysilane dual‐component silane film on the AZ31B Mg alloy surface
Authors: Wang Ying , Yin Minhao , Tang Aiguo , Pang Xianjuan , Yuan Ningyi , Ding Jianning
Published: August 2021

In this paper, the dual‐component silane films composed of trimethoxysilane and bis[3‐(triethoxysilyl)propyl]tetrasulfide (BTESPT) were prepared on the surface of AZ31B Mg alloys. The selected trimethoxysilanes had different chain length. The results showed that the dual‐component silane films could effectively enhance the corrosion resistance of Mg alloys. Moreover, with the enlarging of the chain length of trimethoxysilane, the hydrophobic property and the corrosion resistance of the dual‐component silane films were enhanced. And the dual‐component silane film composed of BTESPT and octadecyltrimethoxysilane (OTMS) showed the highest contact angle and the best corrosion resistance. It could be ascribed to the high density of CH2 groups and –S–S–S–S– in the dual‐component silane film, greatly improving the hydrophobicity and the anticorrosion property. Simultaneously, the substantial Si–O–Si network in the dual‐component silane film also enlarged the length of the penetration paths for corrosive media, delaying the corrosion of the Mg alloy.
High‐Temperature Skin Softening Materials Overcoming the Trade‐Off between Thermal Conductivity and Thermal Contact Resistance
Authors: Kim Taehun , Kim Seongkyun , Kim Eungchul , Kim Taesung , Cho Jungwan , Song Changsik , Baik Seunghyun
Published: August 2021

The trade‐off between thermal conductivity (κ) and thermal contact resistance (Rc) is regarded as a hurdle to develop superior interface materials for thermal management. Here a high‐temperature skin softening material to overcome the trade‐off relationship, realizing a record‐high total thermal conductance (254.92 mW mm−2K−1) for isotropic pad‐type interface materials is introduced. A highly conductive hard core is constructed by incorporating Ag flakes and silver nanoparticle‐decorated multiwalled carbon nanotubes in thermosetting epoxy (EP). The thin soft skin is composed of filler‐embedded thermoplastic poly(ethylene‐co‐vinyl acetate) (PEVA). The κ (82.8 W m−1K−1) of the PEVA‐EP‐PEVA interface material is only slightly compromised, compared with that (106.5 W m−1K−1) of the EP core (386 µm). However, the elastic modulus (E = 2.10 GPa) at the skin is significantly smaller than the EP (26.28 GPa), enhancing conformality and decreasing Rc from 108.41 to 78.73 mm2 K W−1. The thermoplastic skin is further softened at an elevated temperature (100 °C), dramatically decreasing E (0.19 GPa) and Rc (0.17 mm2 K W−1) with little change in κ, overcoming the trade‐off relationship and enhancing the total thermal conductance by 2030%. The successful heat dissipation and applicability to the continuous manufacturing process demonstrate excellent feasibility as future thermal management materials.
MOF‐Derived Fe7S8 Nanoparticles/N‐Doped Carbon Nanofibers as an Ultra‐Stable Anode for Sodium‐Ion Batteries
Authors: Wang Yu , Wen Zi , Wang Chang Chun , Yang Chun Cheng , Jiang Qing
Published: August 2021

Sodium‐ion batteries (SIBs) have aroused wide concern due to their potential applications in large‐scale energy‐storage systems. In this work, a hybrid of Fe7S8 nanoparticles/N‐doped carbon nanofibers (Fe7S8/N‐CNFs) is designed and synthesized via electrospinning. As an anode for SIBs, Fe7S8/N‐CNFs exhibit a high reversible capacity of 649.9 mAh g−1 at 0.2 A g−1 after 100 cycles, and superior cycling stability for 2000 cycles at 1 A g−1 with only 0.00302% capacity decay per cycle. Such excellent performance originates from: i) Fe7S8 nanoparticles (average diameter of 17 nm), which shorten the Na+ diffusion distance; ii) the unique 3D N‐CNFs, which enhance the conductivity, alleviate the self‐agglomeration and large volume change of Fe7S8 nanoparticles, and offer numerous active sites for Na+ adsorption and paths for electrolyte diffusion. The fascinating structure and superior electrochemical properties of Fe7S8/N‐CNFs shed light on developing high‐performance SIBs anode materials.
Comparison of intravenous regional anaesthesia with lidocaine and ropivacaine in dogs
Authors: Imani Rastabi Hadi , Mirzajani Roya , Givi Masoumeh Ezzati , Mohammadpoor Marzieh
Published: August 2021

The present study was designed to compare the effects of lidocaine and ropivacaine in intravenous regional anaesthesia (IVRA) in dogs. Twelve adult male dogs were used. Under isoflurane anaesthesia, exsanguination was performed in the target forelimb. Then, a blood pressure cuff was encircled around the limb proximal to the elbow joint with a pressure of approximately 150 mmHg above the mean arterial blood pressure. The animals then received one of the two treatments of lidocaine (3 mg/kg) or ropivacaine (1.5 mg/kg) with a final volume of 0.6 mL/kg into the cephalic vein. After 60 min, the anaesthesia was disrupted and the tourniquet was removed using intermittent opening (30 s) and closing (5 min) manner for three times. The results revealed that at 20 and 30 min after the initiation of IVRA, the dogs in ROP showed higher analgesia than LID. A leakage under the tourniquet during IVRA was detected. Tremor and hypersalivation were observed after tourniquet removal in some dogs. It was concluded that ropivacaine might provide a higher quality of anaesthesia than lidocaine in IVRA in dogs. The development of local anaesthetic toxicity is a major concern and should be considered at the time of tourniquet removal.
An integrative multiscale view of early cardiac looping
Authors: Ebrahimi Nazanin , Bradley Christopher , Hunter Peter
Published: August 2021

The heart is the first organ to form and function during the development of an embryo. Heart development consists of a series of events believed to be highly conserved in vertebrates. Development of heart begins with the formation of the cardiac fields followed by a linear heart tube formation. The straight heart tube then undergoes a ventral bending prior to further bending and helical torsion to form a looped heart. The looping phase is then followed by ballooning, septation, and valve formation giving rise to a four‐chambered heart in avians and mammals. The looping phase plays a central role in heart development. Successful looping is essential for proper alignment of the future cardiac chambers and tracts. As aberrant looping results in various congenital heart diseases, the mechanisms of cardiac looping have been studied for several decades by various disciplines. Many groups have studied anatomy, biology, genetics, and mechanical processes during heart looping, and have proposed multiple mechanisms. Computational modeling approaches have been utilized to examine the proposed mechanisms of the looping process. Still, the exact underlying mechanism(s) controlling the looping phase remain poorly understood. Although further experimental measurements are obviously still required, the need for more integrative computational modeling approaches is also apparent in order to make sense of the vast amount of experimental data and the complexity of multiscale developmental systems. Indeed, there needs to be an iterative interaction between experimentation and modeling in order to properly find the gap in the existing data and to validate proposed hypotheses.

This article is categorized under:

Cardiovascular Diseases > Genetics/Genomics/Epigenetics

Cardiovascular Diseases > Computational Models

Cardiovascular Diseases > Molecular and Cellular Physiology