bluuebunny/crossref_metadata_2025 huggingface dataset:
Analyzing factors affecting quality of life in patients hospitalized with chronic wound
Authors: Yan Ruihong , Yu Fang , Strandlund Kara , Han Jing , Lei Na , Song Yinghong
Published: October 2020

Background

Studies have reported associations between health‐related quality of life (HRQOL), social support, and mental stress of patients with chronic wound, while the causal relationship is unclear and little is known about the HRQOL of hospitalized them. We therefore investigated the status of HRQOL of hospitalized patients with chronic wound and the causal relationships among social support, mental stress (anxiety and depression) and HRQOL of which.

Methods

A cross‐sectional survey was conducted and the demographic and disease characteristics, HRQOL, perceived social support and mental stress of 216 hospitalized patients with chronic wound was surveyed through questionnaires collected by face to face interview.

Results

(1) The HRQOL of the non‐retired patients was better than that of the retirees (P < .05); Patients with a diabetic foot ulcer, who slept less than 5 hours per night, with moderate pain, wound odor had worse HRQOL (P < .05); Sleep status, diagnosis, and pain scores were entered into the prediction equation of physiological quality of life (PQOL) of the patients (r2 = 0.125, P < .05), retired or not and wound odor were entered into the prediction equation of mental quality of life (MQOL) (r2 = 0.127, P < .05). (2) Perceived social support had a positive predictive effect on the HRQOL of hospitalized patients with chronic wound (β = 1.161, P < .001), and a negative predictive effect on mental stress of them (β = −0.902, P < .001). The effect of social support on the HRQOL of hospitalized patients with chronic wound was to provide a buffering effect on their mental stress, the estimated value was 2.121, 95% CI (1.46, 3.25).

Conclusion

(a) The HRQOL of hospitalized patients with chronic wound was poor and sleep status, diagnosis, pain, retirement status and whether the wound has odor were the main demographic and disease characteristic factors which affected their HRQOL. (2) Perceived social support improved the HRQOL of hospitalized patients with chronic wound by buffering their mental stress.
A New Method for Fault Detection of Rotating Machines in Motion Control Applications Using PROFIdrive Information and Support Vector Machine Classifier
Authors: Dias Andre Luis , Turcato Afonso Celso , Sestito Guilherme Serpa , Rocha Murilo Silveira , Brandão Dennis , Nicoletti Rodrigo
Published: October 2020

Electric motors are widely used in the industry. Several studies have proposed methods to detect anomalies in their operation, but always using sensors dedicated to this purpose. In this sense, this work aims to fill gaps in related works presenting a method for the detection of faults in rotating machines driven by electric motors in motion control applications using PROFINET network and PROFIdrive profile. The proposed method does not require any additional or dedicated sensors to provide data to the diagnostic system. Instead, the proposed methodology is based on the analysis of data transmitted in the communication network, which already exists for control purposes. Support vector machine (SVM) is used as a classifier of five different mechanical faults. The results provide that the methodology is feasible and efficient under different machine operating conditions, achieving, in the worst case, 97.78% efficiency.
Boundary Layers in Darcy–Brinkman Flow
Authors: Wang C. Y.
Published: October 2020

Fluid flow in saturated porous media imbedded with a solid inclusion may be described by the Darcy–Brinkman equation. When the Darcy number is small, a boundary-layer theory, similar to Prandtl's theory for viscous flow, is established. The pressure and shear forces are predicted for Darcy–Brinkman flows over a variety of solid inclusions.
Multidisciplinary Design Optimization for Performance Improvement of an Axial Flow Fan Using Free-Form Deformation
Authors: Adjei Richard Amankwa , Fan Chengwei , Wang WeiZhe , Liu YingZheng
Published: October 2020

This paper describes a multidisciplinary design optimization for performance improvement of an electric-ducted fan rotor using free-form deformation (FFD) and data mining techniques. A practical partitioning approach for FFD parameterization was applied in combination with engineering design parameters to optimize the fan rotor. Regression analysis was used to initially determine an approximation function for the blade static stress and subsequently integrated into a fully coupled iterative loop to optimize the blade considering two operating points. Two optimization solutions for 10 and 12 blades were performed. Percentage improvements in the efficiency of 1.05% and 1.32% were realized for 10 and 12 blades, respectively, at near peak efficiency flowrate. Also, blade static stress was reduced by percentages of 5.49% and 12.37% for 10 and 12 blades compared with the baseline. Data mining results revealed key design variable sensitivities where blade twist, sweep, chord, and hub thickness distribution were found to be the most influential for 12 blades while for 10 blades, blade lean, sweep and chord at the midspan and tip. The optimized blades were found to have a significant increase in chord from midspan to tip mimicking a wide chord fan blade particularly for 10 blades. Analysis of the flow field revealed that the axial velocity from 0.4 to 0.8 spanwise length increased significantly for the optimum blades due to the increase in blade twist and chord length at all stable operating points. However, the leakage trajectory relative to the blade chord was observed to be larger and interacted with the trailing edge wake flow downstream for the optimum blades at near-stall conditions. Furthermore, the increase in chord length and the thinning of the blade close to the trailing edge from 0.4 to 0.8 span reduced the suction-side blade loading and static stress.
Design, Testing, and Performance Impact of Exhaust Diffusers in Aero-Derivative Gas Turbines for Mechanical Drive Applications
Authors: Scotti Del Greco Alberto , Jurek Tomasz , Michelassi Vittorio , Di Benedetto Daniele
Published: October 2020

The growing penetration of renewables calls for power generation and mechanical drive gas turbine (GT) capable of quickly adjusting production and operate at part load. Aero-derivative engine architectures leverage the large experience from aircraft propulsion, have small footprint, high performance, availability, and maintainability. Aircraft engines adjust power with fuel rate and shaft speed that go hand in hand. Mechanical drive engines need to change the delivered power by keeping the shaft speed under control to guarantee the operation of the driven equipment (an LNG compressor or an electric generator). Hence, the power turbine exhaust may deliver velocity and angle profiles that put the discharge diffuser in severe off-design with flow separations, high kinetic losses, and cycle performance shortfall. This paper describes Baker Hughes a GE company experience in the computational fluid dynamics (CFD) assisted design and similitude scale-down testing of aero-derivative hot-end drive exhaust diffusers in multiple operating points. The diffuser inlet conditions reproduce power turbine exit profiles by using swirl vanes and perforated plates, the design of which is heavily CFD assisted. Predictions match measurements in terms of pressure recovery, kinetic losses, and exhaust velocity profiles. Different data postprocessing and averaging are considered to properly factor in the diffuser losses into the overall turbine performance.
Numerical Study on Forced Convection Heat Transfer Across a Heated Circular Tube Based on Bingham Model With Thermally Dependent Viscosity
Authors: Xiao Juan , Wang Simin , Wang Sophie , Dong Jiayu , Wen Jian , Tu Jiyuan
Published: October 2020

The flow and heat transfer performance of Bingham fluid with thermally dependent viscosity across a heated circular tube have been numerically investigated (2408 ≤ ReB ≤ 5852, 9 ≤ Pr ≤ 23 and 10 ≤Bn ≤ 90). The modified bi-viscous Bingham model was used to solve the problem of discontinuous-viscous properties, and a function of temperature known as Arrhenius law was introduced. The results show that unyield regions include a circular shape, pyramid shape, and zones enclosing yield regions at high Reynolds number. Under constant wall temperature boundary, unyield region of temperature-dependent model at rear of circular tube is smaller due to a higher shear rate and lower average viscosity. On the surface of circular tube, local skin drag coefficient first increases and then decreases, and local Nusselt number decreases near rear stagnation point of circular tube illustrating unyield regions of Bingham fluid weaken heat transfer performance. Empirical correlations of average Nusselt number and drag coefficient were obtained based on effects of Reynolds number and Bingham number.
Finite Element Model to Simulate the Spacer Grid Buckling Characteristics
Authors: Yoo Youngik , Kim Joongjin , Eom Kyongbo , Kim Hyeongkoo
Published: October 2020

The purpose of this study is to develop a finite element model that accurately describes the buckling behavior of a spacer grid. The spacer grid is the most important component of a nuclear fuel assembly and supports the fuel rod with a structurally sufficient buckling strength. Therefore, the development of a reliable spacer grid model is essential to evaluate the mechanical integrity of a nuclear fuel assembly. To achieve this objective, a three-dimensional finite element model was proposed to simulate the buckling characteristics and mechanical behavior of a PWR spacer grid.

To simulate the exact mechanical properties of the spacer grid cell, the parameter values required for the model were determined by conducting a fuel rod drag test and spacer grid spring/dimple stiffness test. Finally, a spacer grid static compression test and dynamic impact test were performed according to the gap size of the spacer grid cell, and the model was verified by comparing the test and analysis results. The results obtained using the developed spacer grid finite element model agreed well with the mechanical test results, and it was confirmed that both the buckling characteristics and mechanical behaviors of the model were accurately simulated by the proposed model.
Protection of Nuclear Power Plants Against Severe Winds: Impact of the Local Building Configuration on the Wind Speed to Consider
Authors: Défossez Arièle , Dupont Eric , Grammosenis Laurence , Cordier Hervé , Le Morvan Tiphaine
Published: October 2020

Over the years, power plants have been hit by numerous severe weather events (storm, flood, heat wave...). EDF (Electricity of France) and ASN (Nuclear Safety Authority) want to assess the future impact of severe weather events on the power plants. Furthermore, recent research on storms estimates more accurate wind speed return values than before. For this reason, the severe wind value is an important parameter to quantify on a NPP (Nuclear Power Plant) site, in order to verify if the protection measures are sufficient or, if necessary, to design adequate protection.

To cope with those objectives, wind flow behavior around a PWR (Pressurized Water Reactor) nuclear power plant is studied. The goal of this work is to check that there is no exceeding local wind speed relative to the wind entering the site. The severe winds are characterized locally near the buildings in terms of location and amplitude. Different kind of topology for the nuclear power plant sites are studied in the project: near a cliff, in a plain or in a basin.

In our study, the CFD (Computational Fluid Dynamics) open source tool Code_Saturne developed at EDF-R&D is used to simulate the wind over a French PWR site located in nearly flat terrain in a plain. The 3D mesh includes buildings of the site. Several wind directions corresponding to the prevailing winds are studied. Two wind speeds corresponding to wind speed return values are studied (eg: the inlet wind speed is 25 m/s at 10 meter high for a return period of 50 years). Furthermore, several locations selected near buildings are studied carefully. Swirling flows have been viewed between buildings.

Analysis of the results shows that the wind speed near the buildings does not exceed the wind speed at the entrance of the domain for the three directions studied except near the cooling towers and above buildings. However, this result should not be generalized to other PWR sites due to the specificities of each site such as relief, buildings position, buildings size, roughness, wind rose... This methodology could be applied at other nuclear power plant sites.
Research on Operating Strategy of Total Loss of Essential Service Water System With RHR Not Connected in PWR Unit
Authors: Zhang Shengtao , Yi Ke
Published: October 2020

Essential Service Water System (WES) is part of the nuclear power plant cooling system which provides the final heat sink for nuclear power plants. Therefore, WES must operate stably, safely and reliably for a long time. The total loss of WES accident is a design extended condition and will result in the loss of the final heat sink of the unit. The consequences of the accident are severe. In order to deal with the accident quickly and effectively and ensure the safety and economics of the power plant in accident condition, it’s necessary to formulate corresponding treatment strategy to deal with the transient.

This paper developed a strategy for dealing with the total loss of WES with Residual Heat Removal System (RHR) not connected condition in Generation III nuclear power plant. The structure of the WES system and the types of failures that may occur are analyzed, and thus the symptoms of the faults are obtained and the entry conditions for the operating strategy are determined. The effect of faults on unit equipment and safety functions and the impact on nuclear steam supply system (NSSS) control are analyzed in this paper. Combined with the unit design, the system and equipment for controlling and mitigating related safety functions are analyzed, and the mitigation method and the fallback strategy of the fault are determined. Thereby a complete operating strategy of total loss of WES with RHR not connected is obtained. In addition, this paper analyzes and evaluates the operating strategy by simulating thermal hydraulic calculation for the first time. The results show that without staff intervention Component Cooling System (WCC) temperature reached 55°C limits after running a few minutes. Based on the intervention of the operating strategy proposed in this paper, WCC temperature reached the 55°C limits when the unit was operated at about 4 hours and 55 minutes. The result shows that and the strategy can effectively alleviate the failure and provide sufficient intervention time for the operator to bring the unit to a safe state.
Preliminary Investigation on Improvement of FP Management During BWR Severe Accident With MELCOR-2.2
Authors: Matsubara Kento , Yamaji Akifumi , Li Xin , Fujiwara Daisuke , Shirai Hiroshi , Noujuu Takumi
Published: October 2020

According to the current Boiling Water Reactor (BWR) accident management procedure, the Reactor Pressure Vessel (RPV) is not depressurized until the core water level has decreased to a predetermined threshold level (e.g., 10% of the active fuel length from the bottom of the active fuel (BAF)) when the backup low pressure water injection is unavailable. In the meantime, significant Fission Products (FPs) may be released due to core degradation. In such case, excessive FP deposition on the RPV dome may lead to heat up and failure of the top flange sealing of the Primary Containment Vessel (PCV) due to radiation heat. For BWR4/Mark-I TQUV event, the relationship between the different depressurization timings and FP release and depositions (represented by CsI and CsOH) on RPV (especially, steam dryer and RPV dome), D/W, W/W have been highlighted with MELCOR-2.2 analyses. Overall, it may be understood that the later the depressurization timing, the later the RPV failure timing, but the larger the amount of FP released to RPV. The remaining FP not trapped by water pool were mostly deposited on the RPV steam dryer. Clear correlation between the FP deposition amount on the steam dryer and its temperature could be confirmed. However, more investigations may be necessary to reveal what determines the RPV dome temperature, which seemed to have limited influence on the D/W head temperature profile.
Thermal-Hydraulic Performance Analysis of Fluid Flow in Tube With Helical Screw Inserts in Transition Flow
Authors: Chaurasia Shashank Ranjan , Sarviya R. M.
Published: October 2020

An experimental analysis is arranged to evaluate thermal hydraulic performance analysis on fluid flow in helical screw inserts in tube with number of strips and different twist ratios in Transition flow regime. Single strip insert is also compared with double strip inserts of helical screw inserts with three values of twist ratios. Heat transfer enhancement is achieved with fluid flow in double strip as compared to single strip helical screw insert at decreases values of twist ratios and increases values of Reynolds number (Re). Maximum enhancement in the value of Nusselt number is achieved with double strip inserts at low value of twist ratio and Reynolds number as compared to Single strip inserts. Common correlations of Nusselt number and friction factor are generated. Thermal performance factor (TPF) is achieved maximum values with double strip insert at all flow rates at 2.5 of twist ratio than single strip inserts. Double strip inserts show suitability of helical screw insert in heat exchangers to compact the size of thermal applications.
Research on Probabilistic Safety Assessment (PSA) Method of Safety Class Distributed Control System (DCS) in Nuclear Power Plant Based on Fuzzy Markov Process
Authors: Xufeng Tian , Hao Yan
Published: October 2020

Safety class DCS (Distributed Control System) in nuclear power plant is characterized by multi-state interaction, complex function and unknown fault mechanism, which limits the use of tradition PSA (Probabilistic Safety Assessment) method such as event tree and fault tree. An improved dynamic probabilistic security simulation method is proposed based on fuzzy Markov process to quantitative evaluation the risk of Safety class DCS in nuclear power plant, which resolved the failure uncertainty problem without in-depth understanding of failure mechanism. Firstly, the fuzzy fault tree reliability evaluation model is established based on fuzzy theory and FTA (Fault Tree Analysis), which describes the probability and degree of failure with fuzzy number. Then, the fuzzy fault tree is transformed into fuzzy Markov chain, this model is described mathematically, and the reliability indexes are simulated and analyzed with Monte Carlo simulation method, the change of system safety performance in long-term operation is obtained. Finally, the scientificity and effectiveness is verified by the example of redundant analog output module of safety class DCS in nuclear plant.
Heteroepitaxial growth of β-Ga2O3 films on SiC via molecular beam epitaxy
Authors: Nepal Neeraj , Katzer D. Scott , Downey Brian P. , Wheeler Virginia D. , Nyakiti Luke O. , Storm David F. , Hardy Matthew T. , Freitas Jaime A. , Jin Eric N. , Vaca Diego , Yates Luke , Graham Samuel , Kumar Satish , Meyer David J.
Published: October 2020

β-Ga2O3 is a promising ultrawide bandgap semiconductor for next generation radio frequency electronics. However, its low thermal conductivity and inherent thermal resistance provide additional challenges in managing the thermal response of β-Ga2O3 electronics, limiting its power performance. In this paper, we report the heteroepitaxial growth of β-Ga2O3 films on high thermal conductivity 4H-SiC substrates by molecular beam epitaxy (MBE) at 650 °C. Optimized MBE growth conditions were first determined on sapphire substrates and then used to grow β-Ga2O3 on 4H-SiC. X-ray diffraction measurements showed single phase (2¯01) β-Ga2O3 on (0001) SiC substrates, which was also confirmed by TEM measurements. These thin films are electrically insulating with a (4¯02) peak rocking curve full-width-at-half-maximum of 694 arc sec and root mean square surface roughness of ∼2.5 nm. Broad emission bands observed in the luminescence spectra, acquired in the spectral region between near infrared and deep ultraviolet, have been attributed to donor-acceptor pair transitions possibly related to Ga vacancies and its complex with O vacancies. The thermal conductivity of an 81 nm thick Ga2O3 layer on 4H-SiC was determined to be 3.1 ± 0.5 W/m K, while the measured thermal boundary conductance (TBC) of the Ga2O3/SiC interface is 140 ± 60 MW/m2 K. This high TBC value enables the integration of thin β-Ga2O3 layers with high thermal conductivity substrates to meliorate thermal dissipation and improve device thermal management.
Relationship Between Hip Frontal Dynamic Joint Stiffness and Frontal and Transverse Plane Hip Kinematics During Gait: Sex Differences
Authors: Takano Shogo , Iwamoto Yoshitaka , Ozawa Junya , Kito Nobuhiro
Published: October 2020

Context: Previous studies have reported that the incidence of patellofemoral pain in women is 2.2 times higher than that in men. Lower hip frontal dynamic joint stiffness in women may be related to the magnitude of hip adduction and internal rotation associated with patellofemoral pain. Objective: To identify sex differences in hip frontal dynamic joint stiffness and examine the relationship between hip frontal dynamic joint stiffness and hip adduction and internal rotation during gait. Design: Cross-sectional study. Setting: University campus. Participants: A total of 80 healthy volunteers (40 women and 40 men) participated in this study. Intervention(s): Kinematic and kinetic data during gait were collected using a motion capture system and force plates. Main Outcome Measures: Hip frontal dynamic joint stiffness, hip adduction, and hip internal rotation were calculated during gait. Results: Women demonstrated lower hip frontal dynamic joint stiffness than men during gait (P < .01). They also displayed decreased hip frontal dynamic joint stiffness associated with increased hip adduction (r = −.85, P < .001) and internal rotation (r = −.48, P < .001). Conversely, in men, decreased hip frontal dynamic joint stiffness was associated with increased hip adduction (r = −.74, P < .001) but not internal rotation (r = .17, P = .28). Conclusions: Sex differences between hip frontal dynamic joint stiffness and hip internal rotation during gait may contribute to the increased incidence of patellofemoral pain in women.
Stem cell studies probe origins of the placenta
Authors: Servick Kelly
Published: October 2020

Lab models of organ will track how it emerges—and what can go wrong.
Giant temperature span in electrocaloric regenerator
Authors: Torelló A. , Lheritier P. , Usui T. , Nouchokgwe Y. , Gérard M. , Bouton O. , Hirose S. , Defay E.
Published: October 2020

Competitive cooling with capacitors

Current large-scale cooling devices use vapor compression refrigeration. The efficiency of air conditioners has been optimized, but they can be noisy and rely on problematic greenhouse gases. Two groups now present designs for electrocaloric cooling using lead scandium tantalate capacitors that change temperature under an electric field. Y. Wang
et al.
obtained a very large heat flux using only solid materials and a cooling fan to remove heat from their device. Torello
et al.
used fluids for heat transfer, leading to a very large temperature difference between the hot side and the cold side. The new designs demonstrate the potential for devices that might be competitive with vapor compression–based appliances with further optimization.

Science
, this issue p.
129
, p.
125
A boost for freshwater conservation
Authors: Abell Robin , Harrison Ian J.
Published: October 2020

Integrating freshwater and terrestrial conservation planning has high returns
Fire in our future
Authors: Covington William Wallace , Pyne Stephen
Published: October 2020

It can seem like Earth itself is on fire. In places such as Australia and California for which fire is a natural feature, landscapes are burning at historic if not epic scales. In the Arctic and Greenland, where fire is rare, tundra is smoldering and melting permafrost. In Amazonia, Indonesia, and Mediterranean Europe, fires are interacting with the land clearing of rainforest, the draining of peatlands, and the abandonment of rural lands to create damaging, even lethal, conditions.
Chloroquine Potentiates Primaquine Activity against Active and Latent Hepatic Plasmodia
Ex Vivo
: Potentials and Pitfalls
Authors: Dembélé Laurent , Franetich Jean-François , Soulard Valérie , Amanzougaghene Nadia , Tajeri Shahin , Bousema Teun , van Gemert Geert-Jan , Le Grand Roger , Dereuddre-Bosquet Nathalie , Baird J. Kevin , Mazier Dominique , Snounou Georges
Published: October 2020

For a long while, 8-aminoquinoline compounds have been the only therapeutic agents against latent hepatic malaria parasites. These have poor activity against the blood-stage plasmodia causing acute malaria and must be used in conjunction with partner blood schizontocidal agents. We examined the impacts of one such agent, chloroquine, upon the activity of primaquine, an 8-aminoquinoline, against hepatic stages of
Plasmodium cynomolgi
,
Plasmodium yoelii
,
Plasmodium berghei
, and
Plasmodium falciparum
within several
ex vivo
systems—primary hepatocytes of
Macaca fascicularis
, primary human hepatocytes, and stably transformed human hepatocarcinoma cell line HepG2.
Investigational Antiviral Therapy Models for the Prevention and Treatment of Congenital Cytomegalovirus Infection during Pregnancy
Authors: Hamilton Stuart T. , Marschall Manfred , Rawlinson William D.
Published: October 2020

Congenital cytomegalovirus (HCMV) infection may cause significant fetal malformation, lifelong disease, and, in severe cases, fetal or neonatal death. Placental infection with HCMV is the major mechanism of mother-to-child transmission (MTCT) and fetal injury. Thus, any pharmaceutical antiviral interference to reduce viral load may reduce placental damage, MTCT, and fetal disease. However, there is currently no licensed HCMV antiviral for use during pregnancy. In this study, aciclovir and the HCMV-specific antivirals letermovir, maribavir, and cidofovir were compared with ganciclovir for antiviral effects in model systems of pregnancy, including first-trimester TEV-1 trophoblast cell cultures and third-trimesterex vivoplacental explant histocultures.
Single-Arm Open-Label Clinical Trial of Two Grams of Aztreonam for the Treatment of Neisseria gonorrhoeae
Authors: Barbee Lindley A. , Soge Olusegun O. , Ocbamichael Negusse , LeClair Angela , Golden Matthew R.
Published: October 2020

The threat of ceftriaxone-resistant
Neisseria gonorrhoeae
necessitates new gonorrhea treatment regimens. Repurposing older antibiotics not routinely used for
N. gonorrhoeae
may expeditiously identify new therapies. Ideally, all recommended therapies should eradicate gonorrhea at the pharynx. Between April and September 2019, we enrolled men in an open-label, one-arm clinical trial of single-dose intramuscular aztreonam (2 g). Enrollment criterion included (i) nucleic acid amplification test (NAAT)-positive pharyngeal gonorrhea for ≤14 days or (ii) Gram stain-positive gonococcal urethritis plus report of performing oral sex in ≤2 months.
Gut Bacteria Mediate Nutrient Availability in
Drosophila
Diets
Authors: Lesperance Danielle N. A. , Broderick Nichole A.
Published: October 2020

Both in the laboratory and in nature,
D. melanogaster
-associated microbes serve as nutritional effectors, either through the production of metabolites or as direct sources of protein biomass. The relationship between the microbiome and the resulting host nutritional physiology is significantly impacted by diet composition, yet studies involving
D. melanogaster
are performed using a wide range of artificial diets, making it difficult to discern which aspects of host-microbe interactions may be universal or diet dependent. In this study, we utilized three standard
D. melanogaster
diets and a natural grape diet to form a comprehensive understanding of the quantifiable nutritional changes mediated by the host microbial community. We then altered these artificial diets based on the observed microbe-mediated changes to demonstrate their potential to influence host physiology, allowing us to identify nutritional factors whose effects were either universal for the three artificial diets or dependent on host diet composition.
Sequential Quadriplex Real-Time PCR for Identifying 20 CommonemmTypes of Group AStreptococcus
Authors: Velusamy Srinivasan , Jordak Katherine , Kupor Madeline , Chochua Sopio , McGee Lesley , Beall Bernard
Published: October 2020

We developed a sequential quadriplex real-time PCR-based method for rapid identification of 20emmtypes commonly found in invasive group AStreptococcus(iGAS) strains recovered through the Centers for Disease Control and Prevention’s Active Bacterial Core surveillance. Eachemmreal-time PCR assay showed high specificity and accurately identified the respective targetemmtype, includingemmsubtypes in the United States.
SARS-CoV-2 Is Restricted by Zinc Finger Antiviral Protein despite Preadaptation to the Low-CpG Environment in Humans
Authors: Nchioua Rayhane , Kmiec Dorota , Müller Janis A. , Conzelmann Carina , Groß Rüdiger , Swanson Chad M. , Neil Stuart J. D. , Stenger Steffen , Sauter Daniel , Münch Jan , Sparrer Konstantin M. J. , Kirchhoff Frank
Published: October 2020

Although interferons inhibit SARS-CoV-2 and have been evaluated for treatment of coronavirus disease 2019 (COVID-19), the most effective types and antiviral effectors remain to be defined. Here, we show that IFN-γ is particularly potent in restricting SARS-CoV-2 and in inducing expression of the antiviral factor ZAP in human lung cells. Knockdown experiments revealed that endogenous ZAP significantly restricts SARS-CoV-2. We further show that CpG dinucleotides which are specifically targeted by ZAP are strongly suppressed in the SARS-CoV-2 genome and that the two closest horseshoe bat relatives of SARS-CoV-2 show the lowest genomic CpG content of all coronavirus sequences available from this reservoir host. Nonetheless, both the short and long isoforms of human ZAP reduced SARS-CoV-2 RNA levels, and this activity was conserved in horseshoe bat and pangolin ZAP orthologues. Our findings indicating that type II interferon is particularly efficient against SARS-CoV-2 and that ZAP restricts this pandemic viral pathogen might promote the development of effective immune therapies against COVID-19.
Plasmodium falciparum Apicomplexan-Specific Glucosamine-6-Phosphate
N
-Acetyltransferase Is Key for Amino Sugar Metabolism and Asexual Blood Stage Development
Authors: Chi Jordi , Cova Marta , de las Rivas Matilde , Medina Ana , Borges Rafael Junqueira , Leivar Pablo , Planas Antoni , Usón Isabel , Hurtado-Guerrero Ramón , Izquierdo Luis
Published: October 2020

Apicomplexan parasites cause a major burden on global health and economy. The absence of treatments, the emergence of resistances against available therapies, and the parasite’s ability to manipulate host cells and evade immune systems highlight the urgent need to characterize new drug targets to treat infections caused by these parasites. We demonstrate that glucosamine-6-phosphate
N
-acetyltransferase (GNA1), required for the biosynthesis of UDP-
N
-acetylglucosamine (UDP-GlcNAc), is essential for
P. falciparum
asexual blood stage development and that the disruption of the gene encoding this enzyme quickly causes the death of the parasite within a life cycle. The high-resolution crystal structure of the GNA1 ortholog from the apicomplexan parasite
C. parvum
, used here as a surrogate, highlights significant differences from human GNA1. These divergences can be exploited for the design of specific inhibitors against the malaria parasite.
Levetiracetam for convulsive status epilepticus in childhood: systematic review and meta-analysis
Authors: Abdelgadir Ibtihal , Hamud Ali , Kadri Ayodeji , Akram Shazia , Pullattayil Abdul , Akobeng Anthony K , Powell Colin
Published: October 2020

Importance

Prolonged seizures are life-threatening emergencies associated with significant morbidity.

Objective

To determine the efficacy and safety of levetiracetam in treating convulsive status epilepticus (CSE) in childhood.

Data sources and study selections

PubMed, Embase, the Cochrane Central Register of Controlled Trials and Cumulative Index to Nursing and Allied Health Literature were searched from inception up to April 2020. Only randomised controlled trials (RCTs) that included children aged 1 month–18 years were assessed. Two reviewers performed data assessment and extraction.

Data extraction and synthesis

Ten studies out of the 20 637 citations identified were included.

Main outcomes

Cessation of seizure activities, time to cessation of seizure activities, need for rapid sequence intubation (RSI), intensive care unit (ICU) admission, recurrence of seizures at 24 hours, adverse events and all-cause mortality.

Results

We included 10 RCTs (n=1907). There was no significant difference in cessation of seizure activities when levetiracetam was compared with phenytoin (risk ratio (RR)=1.03, 95% CI 0.98 to 1.09), levetiracetam to fosphenytoin (RR=1.16, 95% CI 1.00 to 1.35) or levetiracetam to valproate (RR=1.10, 95% CI 0.94 to 1.27). No differences were found in relation to the timing of cessation of seizures for levetiracetam versus phenytoin (mean difference (MD)=−0.45, 95% CI −1.83 to 0.93), or levetiracetam versus fosphenytoin (MD=−0.70, 95% CI −4.26 to 2.86). There were no significant differences with regard to ICU admissions, adverse events, recurrence of seizure at 24 hours, RSI and all-cause mortality.

Conclusion

Levetiracetam is comparable to phenytoin, fosphenytoin and valproate as a second line treatment of paediatric CSE.
Efficacy of neoadjuvant atezolizumab treatment in patients with advanced urothelial bladder cancer according to the BASQ classification: a study protocol for an open-label, two-cohort, phase II trial
Authors: Yuk Hyeong Dong , Jeong Chang Wook , Kwak Cheol , Kim Hyeon , Moon Kyung Chul , Ku Ja Hyeon
Published: October 2020

Introduction

Atezolizumab is a programmed death ligand-1 inhibitor for urothelial bladder cancer treatment. Atezolizumab has become the standard therapy for patients with urothelial bladder cancer who are not responding to cisplatin-based chemotherapy and is also used as a first-line treatment in cisplatin-ineligible patients. However, the efficacy of atezolizumab as a neoadjuvant chemotherapy for radical cystectomy has not yet been published and is still under study. This trial investigates the effectiveness of basal/squamous-like (BASQ) classification in the selection of an effective target group of patients with muscle-invasive bladder cancer (MIBC) for neoadjuvant atezolizumab treatment.

Methods and analysis

This study is an open-label, two-cohort, phase II trial. It was designed to evaluate the efficacy of neoadjuvant atezolizumab treatment in patients with MIBC (T2–4N0M0) pathological responses after neoadjuvant chemotherapy and radical cystectomy. According to the molecular subtype characteristics of previous transurethral resection of the bladder specimens, patients are divided into two groups: luminal type (KRT5/6−KRT14−FOXA1+GATA3+) and basal type (KRT5/6+KRT14+FOXA1−GATA3−). Every 3 weeks, atezolizumab is administered at a dose of 1200 mg for three cycles prior to radical cystectomy in patients with MIBC. The primary end point is objective pathological responses in the intention-to-treat patients. The secondary end point is a 1-year progression-free survival difference according to the BASQ classification in patients who underwent neoadjuvant atezolizumab treatment.

Ethics and dissemination

The study protocol was approved by the Institutional Review Board of Seoul National University Hospital, Seoul, Republic of Korea (H 1806-051-950). The trial is registered at ClinicalTrials.gov. The trial results will be published in peer-reviewed journals and at conferences.

Trial registration number

NCT03577132.
Identifying factors associated with high use of acute care in Canada: protocol of a population-based retrospective cohort study
Authors: Zhang Mengmeng , Ma Jinhui , Xie Feng , Thabane Lehana
Published: October 2020

Introduction

High-cost users (HCUs) account for a small proportion of the population but use a disproportionately large share of healthcare resources. Although HCUs exist in all healthcare types, acute care is the most expensive type of service and the most significant contributor to expenditures among HCUs. This study aims to determine demographic, socioeconomic and clinical factors associated with being HCUs in adult patients (≥18 years) receiving acute care in Canada.

Methods and analysis

This is a population-based analysis using a national linked dataset. Adult patients who had at least one interaction with acute care facilities each year from 2011 to 2014 were captured in the dataset, and those living in institutions or other collective residences were not covered. The primary outcome is HCU of acute care (yes/no), which is defined as whether a patient is within the top 10% of the highest acute care cost users in his/her province. Multilevel logistic regression will be used to identify factors associated with HCU and to examine the provincial variations of these identified risk factors. Sensitivity analyses investigating the influences of different high user definitions and missing data on the study results will also be performed.

Ethics and dissemination

All researchers will follow the codes and rules set by Statistics Canada and the Research Data Centre and give priority to the confidentiality of the data during and after this study. The study findings will be published in peer-review journals and disseminated at academic conferences.
Study protocol for the PURSUIT-HFpEF study: a Prospective, Multicenter, Observational Study of Patients with Heart Failure with Preserved Ejection Fraction
Authors: Suna Shinichiro , Hikoso Shungo , Yamada Takahisa , Uematsu Masaaki , Yasumura Yoshio , Nakagawa Akito , Takeda Toshihiro , Kojima Takayuki , Kida Hirota , Oeun Bolrathanak , Sunaga Akihiro , Kitamura Tetsuhisa , Dohi Tomoharu , Okada Katsuki , Mizuno Hiroya , Nakatani Daisaku , Iso Hiroyasu , Matsumura Yasushi , Sakata Yasushi
Published: October 2020

Introduction

Neither the pathophysiology nor an effective treatment for heart failure with preserved ejection fraction (HFpEF) has been elucidated to date. The purpose of this ongoing study is to elucidate the pathophysiology and prognostic factors for patients with HFpEF admitted to participating institutes. We also aim to obtain insights into the development of new diagnostic and treatment methods by analysing patient background factors, clinical data and follow-up information.

Methods and analysis

This study is a prospective, multicentre, observational study of patients aged ≥20 years admitted due to acute decompensated heart failure with preserved left ventricular ejection fraction (≥50%) and elevated N-terminal-pro brain natriuretic peptide (NT-proBNP) (≥400 pg/mL). The study began in June 2016, with the participation of Osaka University Hospital and 31 affiliated facilities. We will collect data on history in detail, accompanying diseases, quality of life, frailty score, medication history, and laboratory and echocardiographic data. We will follow-up each patient for 5 years, and collect outcome data on mortality, cause of death, and the number and cause of hospitalisation. The target number of registered cases is 1500 cases in 5 years.

Ethics and dissemination

The protocol was approved by the Institutional Review Board (IRB) of Osaka University Hospital on 24 February 2016 (ID: 15471), and by the IRBs of the all participating facilities. The findings will be disseminated through peer-reviewed publications and conference presentations.
Experiences of breast feeding at work for physicians, residents and medical students: a scoping review
Authors: Frolkis Alexandra , Michaud Allison , Nguyen Khue-Tu , Bruton Joe Moss , Lithgow Kirstie , Ruzycki Shannon M
Published: October 2020

Objective

To review and summarise the available literature regarding breastfeeding experiences of medical students, residents and physicians.

Eligibility criteria

Articles of any design, including non-peer reviewed data that examine the experiences of breast feeding of medical students, residents and staff physicians.

Information sources

Ovid MEDLINE(R) and Epub Ahead of Print, In-Process & Other Non-Indexed Citations and Daily, Ovid EMBASE, Scopus and Web of Science.

Risk of bias

All peer-reviewed studies underwent risk-of-bias assessment using relevant tools, depending on the study design.

Included studies

We included 71 citations; 51 surveys, 3 narrative descriptions, 9 editorials or letters to the editor, and 3 reviews.

Synthesis of results

Included articles were heterogeneous with respect to their study design, target population and outcomes reported. Most articles had a high risk of bias. Only five articles reported the impact of an intervention.

Description of effect

Despite heterogeneity, the majority of articles described important barriers to breast feeding for physicians, residents and medical students. These barriers were similar across studies, and included inadequate and inaccessible space, time constraints and inflexible scheduling, and lack of colleague support. The consequences of these barriers included low milk supply and early discontinuation of breast feeding.

Strengths and limitations of evidence

Due to the observed heterogeneity of articles identified in this review, we are unable to assess trends in barriers or duration of breastfeeding over time.

Interpretation

Interventions to overcome systemic and cultural barriers to breast feeding are needed to meet legal obligations of workplaces for physicians and trainees. These interventions should be formally evaluated using implementation science or quality improvement methods.
Outbreak of COVID-19 and SARS in mainland China: a comparative study based on national surveillance data
Authors: Zhao Lin , Feng Dan , Ye Run-Ze , Wang Hai-Tao , Zhou Yu-Hao , Wei Jia-Te , J. de Vlas Sake , Cui Xiao-Ming , Jia Na , Yin Chao-Nan , Li Shi-Xue , Wang Zhi-Qiang , Cao Wu-Chun
Published: October 2020

Objective

To compare the epidemiological characteristics and transmission dynamics in relation to interventions against the COVID-19 and severe acute respiratory syndrome (SARS) outbreak in mainland China.

Design

Comparative study based on a unique data set of COVID-19 and SARS.

Setting

Outbreak in mainland China.

Participants

The final database included 82 858 confirmed cases of COVID-19 and 5327 cases of SARS.

Methods

We brought together all existing data sources and integrated them into a comprehensive data set. Individual information on age, sex, occupation, residence location, date of illness onset, date of diagnosis and clinical outcome was extracted. Control measures deployed in mainland China were collected. We compared the epidemiological and spatial characteristics of COVID-19 and SARS. We estimated the effective reproduction number to explore differences in transmission dynamics and intervention effects.

Results

Compared with SARS, COVID-19 affected more extensive areas (1668 vs 230 counties) within a shorter time (101 vs 193 days) and had higher attack rate (61.8 vs 4.0 per million persons). The COVID-19 outbreak had only one epidemic peak and one epicentre (Hubei Province), while the SARS outbreak resulted in two peaks and two epicentres (Guangdong Province and Beijing). SARS-CoV-2 was more likely to infect older people (median age of 52 years), while SARS-CoV tended to infect young adults (median age of 34 years). The case fatality rate (CFR) of either disease increased with age, but the CFR of COVID-19 was significantly lower than that of SARS (5.6% vs 6.4%). The trajectory of effective reproduction number dynamically changed in relation to interventions, which fell below 1 within 2 months for COVID-19 and within 5.5 months for SARS.

Conclusions

China has taken more prompt and effective responses to combat COVID-19 by learning lessons from SARS, providing us with some epidemiological clues to control the ongoing COVID-19 pandemic worldwide.
Targeting the gut-liver-immune axis to treat cirrhosis
Authors: Tranah Thomas Henry , Edwards Lindsey A , Schnabl Bernd , Shawcross Debbie Lindsay
Published: October 2020

Cirrhotic portal hypertension is characterised by development of the decompensating events of ascites, encephalopathy, portal hypertensive bleeding and hepatorenal syndrome, which arise in a setting of cirrhosis-associated immune dysfunction (CAID) and define morbidity and prognosis. CAID describes the dichotomous observations that systemic immune cells are primed and display an inflammatory phenotype, while failing to mount robust responses to pathogen challenge. Bacterial infections including spontaneous bacterial peritonitis are common complications of advanced chronic liver disease and can precipitate variceal haemorrhage, hepatorenal syndrome and acute-on-chronic liver failure; they frequently arise from gut-derived organisms and are closely linked with dysbiosis of the commensal intestinal microbiota in advanced chronic liver disease.

Here, we review the links between cirrhotic dysbiosis, intestinal barrier dysfunction and deficits of host-microbiome compartmentalisation and mucosal immune homoeostasis that occur in settings of advanced chronic liver disease. We discuss established and emerging therapeutic strategies targeted at restoring intestinal eubiosis, augmenting gut barrier function and ameliorating the mucosal and systemic immune deficits that characterise and define the course of decompensated cirrhosis.
Painful metaphors: enactivism and art in qualitative research
Authors: Stilwell Peter , Stilwell Christie , Sabo Brenda , Harman Katherine
Published: October 2020

Enactivism is an emerging theory for sense-making (cognition) with increasing applications to research and medicine. Enactivists reject the idea that sense-making is simply in the head or can be reduced to neural processes. Instead, enactivists argue that cognisers (people) are embodied and action-oriented, and that sense-making emerges from relational processes distributed across the brain-body-environment. We start this paper with an overview of a recently proposed enactive approach to pain. With rich theoretical and empirical roots in phenomenology and cognitive science, conceptualising pain as an enactive process is appealing as it overcomes the problematic dualist and reductionist nature of current pain theories and healthcare practices. Second, we discuss metaphor in the context of pain and enactivism, including a pain-related metaphor classification system. Third, we present and discuss five paintings created alongside an enactive study of clinical communication and the co-construction of pain-related meanings. Each painting represents pain-related metaphors delivered by clinicians during audio-recorded clinical appointments or discussed by clinicians and patients during interviews. We classify these metaphors, connecting them to enactive theory and relevant literature. The art, metaphors and associated narratives draw attention to the intertwined nature of language, meaning and pain. Of clinical relevance to primary and allied healthcare, we explore how clinicians’ taken-for-granted pain-related metaphors can act as scaffolding for patients’ pain and agency, for better or worse. We visually depict and give examples of clinical situations where metaphors became enactive, in that they were clinically reinforced and embodied through assessment and treatment. We conclude with research and clinical considerations, suggesting thatenactive metaphoris a widely overlooked learning mechanism that clinicians could consider employing and intentionally shape.