bluuebunny/crossref_metadata_2025 huggingface dataset:
Experimental Investigation on Heat Transfer and Friction Factor in Open Matrix Subchannels
Authors: Prajapati Anjana N. , Tariq Andallib
Published: January 2021

Matrix cooling has opened new possibilities for enhancing the convective heat transfer coefficients without compromising upon the structural rigidity and the life of the gas turbine blade at elevated temperatures. However, the dense structure of the matrix significantly increases the flow resistance and imposes the limitation to its usage. Recently, a matrix with a gap on the sidewalls called open matrix has been proposed by few researchers to reduce the associated pressure penalties. This detailed experimental investigation aims to study the open matrix channel flow and presents the effects of varying sidewall gaps on heat transfer characteristics and friction factor in the open matrixes having rib angle 45 deg for three different subchannel aspect ratios 1.2, 0.8, and 0.4. Liquid crystal thermography has been utilized to discern the detailed heat transfer characteristics. The results have been evaluated in terms of augmentation Nusselt number, friction factor ratio, and overall thermal performance factor over the Reynolds numbers 5800–14,000. The closed matrixes provided the highest augmentation in Nusselt number, and the gaps on the sidewall have shown an overall reduction in augmentation Nusselt number in most cases. However, the suitable sidewall gaps show the effective reduction in pressure penalties for the smaller subchannel aspect ratios. The highest augmentation Nusselt number among the open matrixes has been found as 3.83 with a reduced friction factor ratio for the matrix with a 4-mm gap in subchannel aspect ratio = 0.8 (i.e., 4 subchannels) at Re = 8100.
Biomechanical Study of Cervical Disc Arthroplasty Devices Using Finite Element Modeling
Authors: Yoganandan Narayan , Purushothaman Yuvaraj , Choi Hoon , Baisden Jamie , Rajasekaran Deepak , Banerjee Anjishnu , Jebaseelan Davidson , Kurpad Shekar
Published: January 2021

Many artificial discs for have been introduced to overcome the disadvantages of conventional anterior discectomy and fusion. The purpose of this study was to evaluate the performance of different U.S. Food and Drug Administration (FDA)-approved cervical disc arthroplasty (CDA) on the range of motion (ROM), intradiscal pressure, and facet force variables under physiological loading. A validated three-dimensional finite element model of the human intact cervical spine (C2-T1) was used. The intact spine was modified to simulate CDAs at C5-C6. Hybrid loading with a follower load of 75 N and moments under flexion, extension, and lateral bending of 2 N·m each were applied to intact and CDA spines. From this work, it was found that at the index level, all CDAs except the Bryan disc increased ROM, and at the adjacent levels, motion decreased in all modes. The largest increase occurred under the lateral bending mode. The Bryan disc had compensatory motion increases at the adjacent levels. Intradiscal pressure reduced at the adjacent levels with Mobi-C and Secure-C. Facet force increased at the index level in all CDAs, with the highest force with the Mobi-C. The force generally decreased at the adjacent levels, except for the Bryan disc and Prestige LP in lateral bending. This study demonstrates the influence of different CDA designs on the anterior and posterior loading patterns at the index and adjacent levels with head supported mass type loadings. The study validates key clinical observations: CDA procedure is contraindicated in cases of facet arthroplasty and may be protective against adjacent segment degeneration.
Best Architecture of an Artificial Neural Network to Model Prefilming Airblast Atomization: Not So Deep Learning
Authors: Chaussonnet G. , Gepperth S. , Holz S. , Koch R. , Bauer H.-J.
Published: January 2021

A fully connected artificial neural network (ANN) is used to predict the spray characteristics of prefilming airblast atomization. The model is trained from the planar prefilmer experiment from the Ph.D. thesis of Gepperth [Experimentelle Untersuchung des Primärzerfalls an generischen luftgestützten Zerstäubern unter Hochdruckbedingungen, Vol. 75. Logos Verlag Berlin GmbH], in which shadowgraphy images of the liquid breakup at the atomizing edge capture the characteristics of the primary droplets and the ligaments. The quantities extracted from the images are the Sauter Mean Diameter, the mean droplet axial velocity, the mean ligament length, and the mean ligament deformation velocity. These are the prescribed output of the ANN model. In total, the training database contains 322 different operating points at which different prefilmers, liquid types, ambient pressures, film loadings, and gas velocities were investigated. Two types of model input quantities are investigated. First, nine dimensional parameters related to the geometry, the operating conditions, and the properties of the liquid are used as inputs for the model. Second, nine nondimensional groups commonly used for liquid atomization are derived from the first set of inputs. These two types of inputs are compared. The architecture providing the best fitting is determined after testing over 10,000 randomly drawn ANN architectures, with up to 10 layers and up to 128 neurons per layer. The striking results is that for both types of model, the best architectures consist of a shallow net with the hidden layers in the form of a diabolo: three layers with a large number of neurons (≥24) in the first and the last layers, and very few neurons (≈12) in middle layer. This shape recalls the shape of an auto-encoder, where the middle layer would be the feature space of reduced dimensionality. The trend highlighted by our results, to have a limited number of layers, is in contrast with recent observations in deep learning applied to computer vision and speech recognition. It was found that the model with dimensional input quantities always shows a lower test and validation errors than the one with nondimensional input quantities. The best architectures for both types of inputs (dimensional and nondimensional input) were tested versus the experiments. Both provide comparable accuracy, which is better than typical correlations of Sauter mean diameter (SMD) and droplet velocity. As the models take more input parameters into account compared to the correlations, they can predict the experimental data more accurately. Finally, the extrapolation capability of the models was assessed by training them on a confined domain of parameters and testing them outside this domain. It was found that the models can extrapolate at larger gas velocity. With a larger ambient pressure or a lower trailing edge thickness, the accuracy decreases drastically.
Implications of Phase Change on the Aerodynamics of Centrifugal Compressors for Supercritical Carbon Dioxide Applications
Authors: Persico Giacomo , Gaetani Paolo , Romei Alessandro , Toni Lorenzo , Bellobuono Ernani Fulvio , Valente Roberto
Published: January 2021

Closed Joule–Brayton cycles operating with carbon dioxide in supercritical conditions (sCO2) are nowadays collecting a significant scientific interest, due to their high potential efficiency, the compactness of their components, and the flexibility that makes them suitable to exploit diverse energy sources. However, the technical implementation of sCO2 power systems introduces new challenges related to the design and operation of the components. The compressor, in particular, operates in a thermodynamic condition close to the critical point, whereby the fluid exhibits significant non-ideal gas effects and is prone to phase change in the intake region of the machine. These new challenges require novel design concepts and strategies, as well as proper tools to achieve reliable predictions. In this study, we consider an exemplary sCO2 power cycle with the main compressor operating in proximity to the critical point, with an intake entropy level of the fluid lower than the critical value. In this condition, the phase change occurs as evaporation/flashing, thus resembling cavitation phenomena observed in liquid pumps, even though with specific issues associated with compressibility effects occurring in both the phases. The flow configuration is therefore highly nonconventional and demands the development of proper tools for fluid and flow modeling, which are instrumental for the compressor design. The paper discusses the modeling issues from the thermodynamic perspective, then highlighting their implications on compressor aerodynamics. We propose tailored models to account for the effect of the phase change in 0D mean-line design tools as well as in fully three-dimensional (3D) computational fluid-dynamic (CFD) simulations: the former was previously validated for sCO2 compressors, the latter is validated in this paper against experiments of compressible flows of supercritical sCO2 in nozzles. In this way, a strategy of investigation is built-up as a combination of mean-line tools, industrial design experience, and CFD for detailed flow analysis. The investigation reveals that the potential onset of the phase change might alter significantly the performance and operation of the compressor, both in design and in off-design conditions, according to three main mechanisms: incidence effect, front-loading, and channel blockage.
Experimental Characterization of Two-Phase Cold Plates Intended for High-Density Data Center Servers Using a Dielectric Fluid
Authors: Ramakrishnan Bharath , Hoang Cong Hiep , Khalili Sadegh , Hadad Yaser , Rangarajan Srikanth , Pattamatta Arvind , Sammakia Bahgat
Published: January 2021

High-performance computing (HPC) data centers demand cutting edge cooling techniques like direct contact liquid cooling (DCLC) for safe and secure operation of their high-power density servers. The two-phase flow boiling heat transfer technique is widely believed to address the heating problem posed by HPC racks. In this study, a novel liquid-cooled cold plate containing microchannel and jet impingement arrangement was characterized for its two-phase flow and thermal behavior. A sophisticated bench top setup involving a mock package was developed to carry out the experiments in a controlled fashion using a dielectric fluid Novec/HFE-7000. Two-phase flow boiling in cold plates which has a strong dependency on surface phenomena were carefully studied at various levels of inlet pressure, subcooling, flow rates, and heat flux levels to the mock package. A resistance network was invoked to determine the average heat transfer coefficient at various exit qualities estimated by the energy balance equation. While the results make it evident that, the high heat generating components can be kept at operable conditions using the two-phase cooling; a deeper insight at the outcomes could pave way for more energy efficient cold plate designs. The experiment was carried out with a large heated surface of 6.45 cm2 and maximum dissipated heat flux was around 63.6 W/cm2 corresponding to chip power of 410 W. Base temperature was kept below 75 °C and pressure drop did not exceed 21 kPa.
Experimental and Model Studies of Various Size Water Droplet Impacting on a Hydrophobic Surface
Authors: Abubakar Abba Abdulhamid , Yilbas Bekir Sami , Hussain A-Qahtani M. , Hassan Ghassan , Yakubu Mubarak , Bahatab Saeed , Adukwu John A. E.
Published: January 2021

Impacting droplet on a hydrophobic surface is investigated and droplet size effect on impacting properties is examined. Liquid pressure variation inside droplet is numerically simulated in the impacting and rebounding periods. Droplet motion on impacted hydrophobic surface is monitored using a high-speed recording system. We showed that predictions and high-speed data for droplet shape and geometric features appear to be almost identical in the spreading and retraction of the droplet on sample surface. Increased volume of droplet gives rise to the peak pressure enhancement in droplet liquid during impact. The maximum droplet height remains larger for large volume droplets in both spreading and retraction cycles. Increasing size of droplet enlarges the wetting diameter on the impacted surface during droplet deformation on sample surfaces. The rate of peak velocity of the spreading surface of the droplet is faster for larger droplets as compared to that corresponding to small droplets. The ratio of spreading period over the retraction period of the droplet becomes small for droplets with small size.
Unsteady Hemodynamics in Intracranial Aneurysms With Varying Dome Orientations
Authors: Usmani Abdullah Y. , Muralidhar K.
Published: January 2021

Fluid loading within an intracranial aneurysm is difficult to measure but can be related to the shape of the flow passage. The outcome of excessive loading is a fatal hemorrhage, making it necessary for early diagnosis. However, arterial diseases are asymptomatic and clinical assessment is a challenge. A realistic approach to examining the severity of wall loading is from the morphology of the aneurysm itself. Accordingly, this study compares pulsatile flow (Reynolds number Re = 426, Womersley number Wo = 4.7) in three different intracranial aneurysm geometries. Specifically, the spatio-temporal movement of vortices is followed in high aspect ratio aneurysm models whose domes are inclined along with angles of 0, 45, and 90 deg relative to the plane of the parent artery. The study is based on finite volume simulation of unsteady three-dimensional flow while a limited set of particle image velocimetry experiments have been carried out. Within a pulsatile cycle, an increase in inclination (0–90 deg) is seen to shift the point of impingement from the distal end toward the aneurysmal apex. This change in flow pattern strengthens helicity, drifts vortex cores, enhances spatial displacement of the vortex, and generates skewed Dean's vortices on transverse planes. Patches of wall shear stress and wall pressure shift spatially from the distal end in models of low inclination (0–45 deg) and circumscribe the aneurysmal wall for an inclination angle of 90 deg. Accordingly, it is concluded that high angles of inclination increase rupture risks while lower inclinations are comparatively safe.
Impaired right ventricular filling in patients with a chronic coronary syndrome
Authors: Sumin Alexey N , Korok Ekaterina V , Sergeeva Tat'ana Yu
Published: January 2021

Aim: The prognostic value of right ventricle (RV) systolic dysfunction is known but the RV diastolic dysfunction (RVDD) is less investigated, thus the purpose of this study was to assess the incidence of RVDD in patients with coronary artery disease (CAD) and to identify factors associated with its presence. Material and methods: We examined 200 patients with stable CAD (153 men). RV diastolic parameters were studied by echocardiography: peak velocity of early (Et) and late (At) RV fill-ing and their ratio, velocities at the tricuspid annulus (et’, a’t, s’t). Patients were divided into 2 groups: with (n=92) and without RVDD (n=108). Results: Old myocardial infarction (MI) (p=0.007), anterior MI (p=0.001), congestive heart failure (p=0.030) and peripheral arterial disease (p=0.030) were more prevalent in patients with RVDD. The end-systolic dimensions were higher (p=0.010), while left ventricular (LV) ejection fraction (EF) (p=0.044) and the mitral E/A ratio (p<0.001) were lower in this group. No significant differences were found between the groups in the coronary artery stenosis. Independent predictors of the RVDD presence were increased age, old MI, hyperlipidemia, moderate chronic heart failure, peripheral arterial disease, and decreased LVEF. Conclusions: The RV diastolic dysfunction is much more common than systolic dysfunction in patients with stable CAD (46% and 7.5%, respectively). The RVDD presence was predominantly associated with an increase in age and LV systolic dysfunction, but not with coronary artery lesions. The predictive value of RVDD requires further research.
Impact of Cr2O3 additives on the gas-sensitive properties of β-Ga2O3 thin films to oxygen, hydrogen, carbon monoxide, and toluene vapors
Authors: Almaev Aleksei V. , Chernikov Evgeny V. , Novikov Vadim V. , Kushnarev Bogdan O. , Yakovlev Nikita N. , Chuprakova Ekaterina V. , Oleinik Vladimir L. , Lozinskaya Anastasiya D. , Gogova Daniela S.
Published: January 2021

High-temperature β-Ga2O3:Cr2O3-based sensors sensitive to oxygen- and hydrogen-containing gases have been developed and studied. Magnetron cosputtering is the method of choice for the thin film synthesis as an industry-compatible technique. The composition-structure-properties relationship has been revealed. An introduction of 0.04–0.14 wt. % Cr leads to a significant increase in the response of the O2 sensors over the temperature range 250–400 °C. The highest response in the above-mentioned temperature range has been achieved for a Cr addition of 0.14 wt. %. An increase in the Cr content from 0.04 to 0.22 wt. % leads to a decrease in the β-Ga2O3-based sensors’ response time, especially for low O2 concentrations (≤10 vol. %). Reliable control of the β-Ga2O3:Cr2O3-based sensors’ selectivity to industry-relevant reducing gases—hydrogen, carbon monoxide, and toluene—is demonstrated. β-Ga2O3 films with a Cr incorporation content of 0.04 and 0.06 wt. % have a high response to toluene at operating temperatures 300–500 °C, while the films with 0.14 and 0.22 wt. % Cr have a high response to H2 in the range 400–500 °C. Regardless of the Cr content in β-Ga2O3 thin films, all sensors considered demonstrate a weak response to CO within the operating temperature range 250–500 °C. The results attained are of certain technological importance, i.e., in terms of the development of cost-effective methods for the synthesis of materials and systems for monitoring and control of industry-relevant gases for an environmentally friendly and sustainable growth.
Interface structure and luminescence properties of epitaxial PbSe films on InAs(111)A
Authors: Haidet Brian B. , Nordin Leland , Muhowski Aaron J. , Vallejo Kevin D. , Hughes Eamonn T. , Meyer Jarod , Simmonds Paul J. , Wasserman Daniel , Mukherjee Kunal
Published: January 2021

Epitaxial heterostructures of narrow-gap IV-VI and III-V semiconductors offer a platform for new electronics and mid-infrared photonics. Stark dissimilarities in the bonding and the crystal structure between the rocksalt IV–VIs and the zincblende III–Vs, however, mandate the development of nucleation and growth protocols to reliably prepare high-quality heterostructures. In this work, we demonstrate a route to single crystal (111)-oriented PbSe epitaxial films on nearly lattice-matched InAs (111)A templates. Without this technique, the high-energy heterovalent interface readily produces two populations of PbSe grains that are rotated 180° in-plane with respect to each other, separated by rotational twin boundaries. We find that a high-temperature surface treatment with the PbSe flux extinguishes one of these interfacial stackings, resulting in single-crystalline films with interfaces that are mediated by a monolayer of distorted PbSe. While very thin PbSe-on-InAs films do not emit light, hinting toward a type-III band alignment, we see strong room temperature photoluminescence from a 1.5 μm thick film with a minority carrier lifetime of 20 ns at low-excitation conditions and bimolecular recombination at high excitation conditions, respectively, even with threading dislocation densities exceeding 108 cm−2. We also note near-complete strain relaxation in these films despite large thermal expansion mismatch to the substrate, with dislocations gliding to relieve strain even at cryogenic temperatures. These results bring to light the exceptional properties of IV-VI semiconductors and the new IV-VI/III-V interfaces for a range of applications in optoelectronics.
Estimating target strength and physical characteristics of gas-bearing mesopelagic fish from wideband in situ echoes using a viscous-elastic scattering model
Authors: Khodabandeloo Babak , Agersted Mette Dalgaard , Klevjer Thor , Macaulay Gavin J. , Melle Webjørn
Published: January 2021

Wideband (38 and 50–260 kHz) target strength of organisms were measured in situ using a towed platform in mesopelagic (200–1000 m depth) layers. Organisms with a gas-inclusion are strong scatterers of sound and acoustically distinct from organisms lacking one. In the mesopelagic zone, some of the fish species and physonect siphonophores have a gas-inclusion. Trawl and multinet biological sampling as well as photographic evidence indicate that in the study area (eastern mid-Atlantic Ocean) the majority of the gas-bearing organisms were fish. Subsequently, using a two-layer viscous-elastic spherical gas backscattering model, physical characteristics such as gas-bladder features and body flesh properties were deduced from the measured backscattering signal of individual gas-bearing fish. Acoustic techniques are non-extractive, can be used for the monitoring and quantification of marine organisms in a time- and cost-effective manner, and suit studies of the mesopelagic zone, which is logistically challenging. Vessel-mounted acoustics, widely used for epipelagic studies, has limitations for mesopelagic studies as the deep organisms are inaccessible to high-frequency (≳100 kHz) acoustic pulses transmitted from the surface due to absorption. Therefore, a towed platform equipped with wideband acoustics has several features that can be utilized for monitoring the mesopelagic dense scattering layers containing mixed species.
ACOUSTICAL NEWS
Authors: Moran Elaine
Published: January 2021

Editor's Note: Readers of this journal are encouraged to submit news items on awards, appointments, and other activities about themselves or their colleagues. Deadline dates for news and notices are 2 months prior to publication.
Implementing Strength Training Strategies for Injury Prevention in Soccer: Scientific Rationale and Methodological Recommendations
Authors: Beato Marco , Maroto-Izquierdo Sergio , Turner Anthony N. , Bishop Chris
Published: January 2021

Due to the negative effects that injuries have on performance, club finances, and long-term player health (permanent disability after a severe injury), prevention strategies are an essential part of both sports medicine and performance.Purpose:To summarize the current evidence regarding strength training for injury prevention in soccer and to inform its evidence-based implementation in research and applied settings.Conclusions:The contemporary literature suggests that strength training, proposed as traditional resistance, eccentric, and flywheel training, may be a valid method to reduce injury risk in soccer players. Training strategies involving multiple components (eg, a combination of strength, balance, plyometrics) that include strength exercises are effective at reducing noncontact injuries in female soccer players. In addition, the body of research currently published supports the use of eccentric training in sports, which offers unique physiological responses compared with other resistance exercise modalities. It seems that the Nordic hamstring exercise, in particular, is a viable option for the reduction of hamstring injuries in soccer players. Moreover, flywheel training has specific training peculiarities and advantages that are related to the combination of both concentric and eccentric contraction, which may play an important role in injury prevention. It is the authors’ opinion that strength and conditioning coaches should integrate the strength training methods proposed here in their weekly training routine to reduce the likelihood of injuries in their players; however, further research is needed to verify the advantages and disadvantages of these training methods to injury prevention using specific cohorts of soccer players.
Fibrillin-1–enriched microenvironment drives endothelial injury and vascular rarefaction in chronic kidney disease
Authors: Li Li , Liao Jinlin , Yuan Qian , Hong Xue , Li Jing , Peng Yiling , He Meizhi , Zhu Haili , Zhu Mingsheng , Hou Fan Fan , Fu Haiyan , Liu Youhua
Published: January 2021

The study illustrates a crucial role of tissue microenvironment in mediating endothelial dropout and vascular rarefaction.
Nondestructive, high-resolution, chemically specific 3D nanostructure characterization using phase-sensitive EUV imaging reflectometry
Authors: Tanksalvala Michael , Porter Christina L. , Esashi Yuka , Wang Bin , Jenkins Nicholas W. , Zhang Zhe , Miley Galen P. , Knobloch Joshua L. , McBennett Brendan , Horiguchi Naoto , Yazdi Sadegh , Zhou Jihan , Jacobs Matthew N. , Bevis Charles S. , Karl Robert M. , Johnsen Peter , Ren David , Waller Laura , Adams Daniel E. , Cousin Seth L. , Liao Chen-Ting , Miao Jianwei , Gerrity Michael , Kapteyn Henry C. , Murnane Margaret M.
Published: January 2021

A new imaging technique enables nondestructive, 3D characterization of nanostructures, their composition, and interfaces.
Genome-wide CRISPR-Cas9 screen identified KLF11 as a druggable suppressor for sarcoma cancer stem cells
Authors: Wang Yicun , Wu Jinhui , Chen Hui , Yang Yang , Xiao Chengwu , Yi Xiaoming , Shi Changjie , Zhong Ke , He Haowei , Li Yaoming , Wu Zhenjie , Zhou Guangxin , Rao Qiu , Wang Xiaoxia , Zhou Xiaodie , Lomberk Gwen , Liu Bing , Zhao Jianning , Ge Jingping , Zhou Wenquan , Chu Xiaoyuan , Chen Cheng , Zhou Xuhui , Wang Linhui , Guan Kunliang , Qu Le
Published: January 2021

KLF11 is a negative regulator of CSC stemness in sarcoma by repressing YAP/TEAD-dependent transcription.
Toward robust mammography-based models for breast cancer risk
Authors: Yala Adam , Mikhael Peter G. , Strand Fredrik , Lin Gigin , Smith Kevin , Wan Yung-Liang , Lamb Leslie , Hughes Kevin , Lehman Constance , Barzilay Regina
Published: January 2021

An algorithm to predict breast cancer risk, Mirai, outperforms clinical risk models across test cohorts from the United States, Sweden, and Taiwan.
In Vitro
and
In Vivo
Antibacterial Activities of a Novel Quinolone Compound, OPS-2071, against Clostridioides difficile
Authors: Oka Daisuke , Yamaya Naomitsu , Kuno Takuya , Asakawa Yuta , Shiragiku Toshiyuki , Chen Liang , Xue Jingbo , Mamuti Abudusaimi , Ye Fangguo , Sun Jiangqin , Ohguro Kinue , Miyamoto Hisashi , Uematsu Yukitaka , Inagaki Katsuya , Cheng Jie-Fei , Matsumoto Makoto
Published: January 2021

OPS-2071 is a novel quinolone antibacterial agent characterized by low oral absorption that reduces the risk of adverse events typical of fluoroquinolone class antibiotics. The
in vitro
and
in vivo
antibacterial activities of OPS-2071 against
Clostridioides difficile
were evaluated in comparison to vancomycin and fidaxomicin.
Artemisinin-Based Drugs Target the Plasmodium falciparum Heme Detoxification Pathway
Authors: Ribbiso Kaleab A. , Heller Laura E. , Taye Abigail , Julian Erin , Willems Andreas V. , Roepe Paul D.
Published: January 2021

Artemisinin (ART)-based antimalarial drugs are believed to exert lethal effects on malarial parasites by alkylating a variety of intracellular molecular targets. Recent work with live parasites has shown that one of the alkylated targets is free heme within the parasite digestive vacuole, which is liberated upon hemoglobin catabolism by the intraerythrocytic parasite, and that reduced levels of heme alkylation occur in artemisinin-resistant parasites.
A New SARS-CoV-2 Dual-Purpose Serology Test: Highly Accurate Infection Tracing and Neutralizing Antibody Response Detection
Authors: Taylor Sean C. , Hurst Beth , Charlton Carmen L. , Bailey Ashley , Kanji Jamil N. , McCarthy Mary K. , Morrison Thomas E. , Huey Leah , Annen Kyle , DomBourian Melkon G. , Knight Vijaya
Published: January 2021

Many severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) serology tests have proven to be less accurate than expected and do not assess antibody function as neutralizing, correlating with protection from reinfection. A new assay technology measuring the interaction of the purified SARS-CoV-2 spike protein receptor binding domain (RBD) with the extracellular domain of the human angiotensin-converting enzyme 2 (hACE2) receptor detects these important antibodies.
Complete Genome Sequences of 12 Quinolone-Resistant Escherichia coli Strains Containing
qnrS1
Based on Hybrid Assemblies
Authors: Kaspersen Håkon , Haverkamp Thomas H. A. , Ilag Hanna Karin , Øines Øivind , Sekse Camilla , Slettemeås Jannice Schau
Published: January 2021

In total, 12 quinolone-resistant
Escherichia coli
(QREC) strains containing
qnrS1
were submitted to long-read sequencing using a FLO-MIN106 flow cell on a MinION device. The long reads were assembled with short reads (Illumina) and analyzed using the MOB-suite pipeline. Six of these QREC genome sequences were closed after hybrid assembly.
The Fifth International Neonatal and Maternal Immunization Symposium (INMIS 2019): Securing Protection for the Next Generation
Authors: Sadarangani Manish , Kollmann Tobias , Bjornson Gordean , Heath Paul , Clarke Ed , Marchant Arnaud , Levy Ofer , Leuridan Elke , Ulloa-Gutierrez Rolando , Cutland Clare L. , Kampmann Beate , Chaithongwongwatthana Surasith , Dinleyici Ener , van Damme Pierre , Munoz Flor M.
Published: January 2021

Despite significant progress in reaching some milestones of the United Nations Sustainable Development Goals, neonatal and early infant morbidity and mortality remain high, and maternal health remains suboptimal in many countries. Novel and improved preventative strategies with the potential to benefit pregnant women and their infants are needed, with maternal and neonatal immunization representing effective approaches.
Supplemental Material: Regional fault-controlled shallow dolomitization of the Middle Cambrian Cathedral Formation by hydrothermal fluids fluxed through a basal clastic aquifer
Authors: Stacey Jack , al. et
Published: January 2021

Geochemical data for dolomite and limestone (trace element, rare earth element, carbon and oxygen stable isotope, clumped oxygen isotope, noble gas, fluid inclusion and bulk rock XRD) of the Middle Cambrian Cathedral Formation, Southern Canadian Rocky Mountains.
No change in neurodevelopment at 11 years after extremely preterm birth
Authors: Marlow Neil , Ni Yanyan , Lancaster Rebecca , Suonpera Emmi , Bernardi Marialivia , Fahy Amanda , Larsen Jennifer , Trickett Jayne , Hurst John R , Morris Joan , Wolke Dieter , Johnson Samantha
Published: January 2021

Objective

To determine whether improvements in school age outcomes had occurred between two cohorts of births at 22–25 weeks of gestation to women residents in England in 1995 and 2006.

Design

Longitudinal national cohort studies.

Setting

School-based or home-based assessments at 11 years of age.

Participants

EPICure2 cohort of births at 22–26 weeks of gestation in England during 2006: a sample of 200 of 1031 survivors were evaluated; outcomes for 112 children born at 22–25 weeks of gestation were compared with those of 176 born in England during 1995 from the EPICure cohort. Classroom controls for each group acted as a reference population.

Main outcome measures

Standardised measures of cognition and academic attainment were combined with parent report of other impairments to estimate overall neurodevelopmental status.

Results

At 11 years in EPICure2, 18% had severe and 20% moderate impairments. Comparing births at 22–25 weeks in EPICure2 (n=112), 26% had severe and 21% moderate impairment compared with 18% and 32%, respectively, in EPICure. After adjustment, the OR of moderate or severe neurodevelopmental impairment in 2006 compared with 1995 was 0.76 (95% CI 0.45 to 1.31, p=0.32). IQ scores were similar in 1995 (mean 82.7, SD 18.4) and 2006 (81.4, SD 19.2), adjusted difference in mean z-scores 0.2 SD (95% CI −0.2 to 0.6), as were attainment test scores. The use of multiple imputation did not alter these findings.

Conclusion

Improvements in care and survival between 1995 and 2006 are not paralleled by improved cognitive or educational outcomes or a reduced rate of neurodevelopmental impairment.
Abdominal wall actinomycotic mycetoma involving the bowel: a rare entity
Authors: Sharma Anuj Kumar , Pandey Alok Kumar , Kaistha Sumesh , Ranjan Kumar Rajesh
Published: January 2021

Actinomycotic mycetoma is a disease of the tropical region and usually presents as a chronic, suppurative and deforming granulomatous infection. We present an unusual case of actinomycotic mycetoma of the abdominal wall that was found to infiltrate into the bowel. A 51 year-old man presented with pain and swelling in the left flank of 2-year duration. Even after comprehensive preoperative evaluation with advanced radiological imaging, biochemistry and pathology, the diagnosis could not be arrived at. Histopathological examination of the excised specimen after the surgery guided to the diagnosis of actinomycotic mycetoma, which entirely changed the management in the postoperative period. We propose that mycetoma should be kept as a possible differential diagnosis for anterior abdominal wall swelling in the indicated clinical setting and the investigations be done keeping the same in mind. Otherwise, a lot of valuable time may be lost allowing the disease to progress further.
Rapidly progressive stridor in a case of GIST
Authors: Serex Charles-Arnaud , Dulguerov Nicolas
Published: January 2021

We report the case of an 84-year-old male patient suffering from a gastrointestinal stromal tumour (GIST) of the rectum who was referred to our ENT (Ear-Nose-Throat) clinic for a rapidly progressive stridor, aphagia and dysphonia. The clinical examination revealed a mass arising from the posterior wall of the pharynx, which obstructed the laryngeal inlet and thus the airway. A metastasis of the GIST was suspected. After completing the investigation with radiological imaging, the patient underwent surgery, which consisted of a tracheostomy to secure the airway and a biopsy of the mass. The pathological examination confirmed the suspected diagnosis of a GIST vertebral metastasis.
Neuromyelitis optica spectrum disorder (NMOSD) presenting as acute transverse myelitis with positive aquaporin 4 antibodies
Authors: Thornley Katherine , Canepa Carlo
Published: January 2021

An 80-year-old, previously healthy patient presents with acute transverse myelitis with sensory level at T8. The MRI scan of the spinal cord showed longitudinal extensive transverse myelitis, and she tested positive for aquaporin 4 antibodies in serum. She received treatment with intravenous and oral steroids, with no improvement and then underwent plasma exchange. She was then started on azathioprine for prevention of relapses, while continuing physiotherapy and occupational therapy. Eventually, she was transferred to a specialised spinal cord centre for long-term rehabilitation.
Acquired von Willebrand syndrome in association with multiple myeloma: remission after stem cell transplant
Authors: Shah Chintan P , Delaune Jess , Mandernach Molly W
Published: January 2021

Acquired von Willebrand syndrome is a rare bleeding disorder characterised by a later age of onset without a personal or family history of bleeding diathesis. It is vital to discern acquired von Willebrand syndrome from inherited von Willebrand disease and other acquired bleeding disorders as management differs significantly. Acquired von Willebrand syndrome is usually secondary to an underlying disorder such as lymphoproliferative disorder, myeloproliferative neoplasm, solid tumour, cardiovascular disorder, autoimmune disorders or hypothyroidism. Diagnosis is often delayed with a significant risk of morbidity and even mortality. Here we present a case of a 74-year-old man with an acquired bleeding disorder and work up suggestive of acquired von Willebrand syndrome secondary to immunoglobulin G kappa multiple myeloma. He was treated successfully with intravenous immunoglobulin, von Willebrand Factor/Coagulation Factor VIII Complex (human), myeloma directed chemotherapy and autologous stem cell transplantation. We also discuss the management strategies that are largely based on retrospective studies and case reports.
Single modality radical radiotherapy is an acceptable alternative for the older patient with squamous cell carcinoma of the oesophagus
Authors: Derby Sarah , Forshaw Matthew , Lowrie Caroline , Grose Derek , Marashi Husam , McLoone Philip , Wilson Christina , McIntosh David
Published: January 2021

Background

Oesophageal cancer remains a common cause of cancer mortality worldwide. Increasingly, oncology centres are treating an older population and comorbidities may preclude multimodality treatment with chemoradiotherapy (CRT). We review outcomes of radical radiotherapy (RT) in an older population treating squamous cell carcinoma (SCC) oesophagus.

Methods

Patients over 65 years receiving RT for SCC oesophagus between 2013 and 2016 in the West of Scotland were identified. Kaplan-Meier and Cox-regression analysis were used to compare overall survival (OS) between patients treated with radical RT and radical CRT.

Results

There were 83 patients over 65 years treated with either RT (n=21) or CRT (n=62). There was no significant difference in median OS between CRT versus RT (26.8 months vs 28.5 months, p=0.92). All patients receiving RT completed their treatment whereas 11% of CRT patients did not complete treatment.

Conclusion

Survival in this non-trial older patient group managed with CRT is comparable to that reported in previous trials. RT shows better than expected outcomes which may reflect developments in RT technique. This review supports RT as an alternative in older patients, unfit for concurrent treatment.
Neurological implications of COVID-19: a review of the science and clinical guidance
Authors: Tan Lynn , Lin Zhiliang Caleb , Ray Jason , Wesselingh Robb , Oxley Thomas J , McFadyen James , Kapoor Mahima , Hutton Elspeth
Published: January 2021

COVID-19 is a significant global health burden. The pulmonary morbidity and mortality of COVID-19 is well described, however, there is mounting evidence of neurological manifestations of SARS-CoV-2, which may be of prognostic significance. This paper summarises the available evidence in order to provide clinicians with a concise summary of the peripheral and central neurological manifestations of COVID-19, discusses specific issues regarding the management of chronic neurological disease in the context of the pandemic, and provides a summary of the thrombotic implications of the disease for the neurologist.
Examining chronic inflammatory markers on blood pressure measures in the presence of vitamin D insufficiency among indigenous cree adults: results from the cross-sectional Multi-Community Environment-and-Health Study inEeyou Istchee, Quebec, Canada
Authors: Zuk Aleksandra M , Liberda Eric N , Tsuji Leonard J S
Published: January 2021

Objective

High blood pressure (BP) is a risk factor for cardiovascular disease. Examining the role of inflammatory mediators on BP is important since vitamin D (VD) is a modifiable risk factor, which possibly modulates inflammatory cytokines. This study simulated what are known as average ‘controlled direct effects (CDE)’ of inflammatory markers, C reactive protein (CRP), tumour necrosis factor-α (TNF-α), and interlukin-6 (IL-6) on continuous BP measures, while fixing VD, an intermediate variable to specific level.

Design

Cross-sectional study.

Setting

We analysed data from the Multi-Community Environment-and-Health Study, 2005–2009, conducted inEeyou Istchee, Quebec, Canada.

Participants

This study recruited 1425 study Indigenous Cree participants from seven Cree communities. Only adults with serum VD levels, inflammatory markers and BP measures were included in this data analysis.

Primary and secondary outcomes measures

Inflammatory markers examined the top 25th exposure percentiles. VD ‘insufficiency’ (ie, 25-hydroxyvitamin-D levels<50 nmol/L) defined by the Institute of Medicine. CDE for each inflammatory marker in the presence and absence of population VD insufficiency simulated the average direct effect change for systolic and diastolic BP (SBP and DBP) measures. All models were adjusted for exposure-and-mediator outcome relationship.

Results

Among 161 participants, 97 (60 %) were female. The prevalence of VD insufficiency was 32%. CDE estimates show in the presence and absence of population vitamin D insufficiency, inflammatory markers have a slightly different association on BP. TNF-α significantly and inversely associated with SBP in the presence of vitamin D insufficiency, fully adjusted model β = −13.61 (95% CI −24.42 to −2.80); however, TNF-α was not associated with SBP in the absence of vitamin D insufficiency. CRP, IL-6 were also not significantly associated with BP measures, although the magnitude of association was greater for those with elevated inflammation and VD insufficiency.

Conclusion

This novel analysis shows in the presence of VD insufficiency, inflammation (particularly TNF-α) may affect SBP. Additional research is needed to elucidate these findings, and the temporal relationship between these variables.
Antiplatelet therapy in patients with myocardial infarction without obstructive coronary artery disease
Authors: Bossard Matthias , Gao Peggy , Boden William , Steg Gabriel , Tanguay Jean-Francois , Joyner Cam , Granger Christopher B , Kastrati Adnan , Faxon David , Budaj Andrzej , Pais Prem , Di Pasquale Giuseppe , Valentin Vicent , Flather Marcus , Moccetti Tiziano , Yusuf Salim , Mehta Shamir R
Published: January 2021

Objective

Approximately 10% of patients with myocardial infarction (MI) have no obstructive coronary artery disease. The prognosis and role of intensified antiplatelet therapy in those patients were evaluated.

Methods

We analysed data from the Clopidogrel and Aspirin Optimal Dose Usage to Reduce Recurrent Events–Seventh Organisation to Assess Strategies in Ischaemic Symptoms trial randomising patients with ACS referred for early intervention to receive either double-dose (600 mg, day 1; 150 mg, days 2–7; then 75 mg/day) or standard-dose (300 mg, day 1; then 75 mg/day) clopidogrel. Outcomes in patients with myocardial infarction with non-obstructive coronary arteries (MINOCA) versus those with obstructive coronary artery disease (CAD) and their relation to standard-dose versus double-dose clopidogrel were evaluated. The primary outcome was cardiovascular (CV) death, MI or stroke at 30 days.

Results

We included 23 783 patients with MI and 1599 (6.7%) with MINOCA. Patients with MINOCA were younger, presented more frequently with non-ST-segment elevation MI and had fewer comorbidities. All-cause mortality (0.6% vs 2.3%, p=0.005), CV mortality (0.6% vs 2.2%, p=0.006), repeat MI (0.5% vs 2.3%, p=0.001) and major bleeding (0.6% vs 2.4%, p<0.0001) were lower among patients with MINOCA than among those with obstructive CAD. Among patients with MINOCA, 2.1% of patients in the double-dose clopidogrel group and 0.6% in the standard-dose group experienced a primary outcome (HR 3.57, 95% CI 1.31 to 9.76), whereas in those with obstructive CAD, rates were 4.3% and 4.7%, respectively (HR 0.91, 95% CI 0.80 to 1.03; p value for interaction=0.011).

Conclusions

Patients with MINOCA are at lower risk of recurrent CV events compared with patients with MI with obstructive CAD. Compared with a standard clopidogrel-based dual antiplatelet therapy (DAPT) regimen, an intensified dosing strategy appears to offer no additional benefit with a signal of possible harm. Further randomised trials evaluating the effects of potent DAPT in patients with MINOCA are warranted.

Trial registration number

NCT00335452.
Structural racism, racial inequities and urban–rural differences in infant mortality in the US
Authors: Vilda Dovile , Hardeman Rachel , Dyer Lauren , Theall Katherine P , Wallace Maeve
Published: January 2021

Background

While evidence shows considerable geographic variations in county-level racial inequities in infant mortality, the role of structural racism across urban–rural lines remains unexplored. The objective of this study was to examine the associations between county-level structural racism (racial inequity in educational attainment, median household income and jail incarceration) and infant mortality and heterogeneity between urban and rural areas.

Methods

Using linked live birth/infant death data provided by the National Center for Health Statistics, we calculated overall and race-specific 2013–2017 5-year infant mortality rates (IMRs) per 1000 live births in every county. Racially stratified and area-stratified negative binomial regression models estimated IMR ratios and 95% CIs associated with structural racism indicators, adjusting for county-level confounders. Adjusted linear regression models estimated associations between structural racism indicators and the absolute and relative racial inequity in IMR.

Results

In urban counties, structural racism indicators were associated with 7%–8% higher black IMR, and an overall structural racism score was associated with 9% greater black IMR; however, these findings became insignificant when adjusting for the region. In white population, structural racism indicators and the overall structural racism score were associated with a 6% decrease in urban white IMR. Both absolute and relative racial inequity in IMR were exacerbated in urban counties with greater levels of structural racism.

Conclusions

Our findings highlight the complex relationship between structural racism and population health across urban–rural lines and suggest its contribution to the maintenance of health inequities in urban settings.
Strengthened impairment argument: restating Marquis?
Authors: Gillham Alex
Published: January 2021

Blackshaw and Hendricks recently developed a strengthened version of the impairment argument (SIA) that imports Marquis’ account of the wrongness of abortion. I then argued that if SIA imports Marquis’ account, then it restates Marquis’ position and thus is not very significant. In turn, Blackshaw and Hendricks explained why they take SIA to be importantly different from Marquis’ account. I have two aims in this response. First, I reconstruct Blackshaw and Hendricks’ arguments for the claim that SIA is importantly different from Marquis’ account. Second, I argue that SIA is not importantly different from Marquis’ account in the respect that Blackshaw and Hendricks take it to be.
Do differences in work disability duration by interjurisdictional claim status vary by industry and jurisdictional context?
Authors: Macpherson Robert A , Koehoorn Mieke , Neis Barbara , McLeod Christopher B
Published: January 2021

Objectives

To examine whether differences in work disability duration between out-of-province and within-province workers differed by industry and jurisdictional context.

Methods

Workers’ compensation data were used to identify comparable lost time, work-related injury and musculoskeletal disorder claims accepted in six Canadian jurisdictions between 2006 and 2015. Out-of-province workers were identified as workers who filed claims in a different provincial jurisdiction to their province of residence. Coarsened exact matching was used to match out-of-province workers with within-province workers based on observable characteristics. Quantile regression models were used to estimate differences in cumulative disability days paid between out-of-province workers and within-province workers at different percentiles in the disability distribution, adjusting for confounders.

Results

Compared with within-province workers, out-of-province workers were paid more disability days even after matching and adjusting on observable characteristics. Differences between the two groups of workers were observed for short-duration, medium-duration and long-duration claims (differences of 1.57, 6.39, 21.42, 46.43 days at the 25th, 50th, 75th and 90th percentiles, respectively). Industry-specific models showed that differences were largest in construction, transportation and warehousing, and mining, quarrying and oil and gas extraction. Jurisdiction-specific models showed that differences were largest in the western provinces where out-of-province workers were concentrated in those sectors.

Conclusions

Out-of-province workers are a vulnerable group with respect to risk of longer work disability duration. Workers’ compensation systems, employers and healthcare providers may need to tailor specific interventions for these types of workers, particularly those employed in resource economy-dependent regions that are far from their regions of residence.