bluuebunny/crossref_metadata_2025 huggingface dataset:
Influence of copper damper on bifurcation vibration in superconductive magnetic levitation system
Authors: Huang Yi , Li Hui
Published: September 2020

With proper external vibrations, the dynamic behavior of a high-temperature superconducting levitation system will show interesting bifurcation and complex chaos. In order to eliminate the effects of nonlinear vibrations, a larger magnetic force generated by a high-temperature superconductor (HTSC) with strong flux pinning is necessary. However, it provides minimal inherent damping. In this article, we numerically studied the effect of different copper damper arrangements on the superconductive magnetic levitation system in nonlinear vibration by the finite element method. Furthermore, we compared the results with and without a copper damper by analyzing the displacements, temperature differences, and electromagnetic forces (HTSC and copper). The results indicate that adjusting the copper damping can increase the interference rejection capacity of the superconductive magnetic levitation system.
Shear dynamics of confined bijels
Authors: Bonaccorso F. , Succi S. , Lauricella M. , Montessori A. , Tiribocchi A. , Luo K. H.
Published: September 2020

Bicontinuous interfacially jammed emulsion gels (“bijels”) represent a new class of soft materials made of a densely packed monolayer of solid particles sequestered at the interface of a bicontinuous fluid. Their mechanical properties are relevant to many applications, such as catalysis, energy conversion, soft robotics, and scaffolds for tissue engineering. While their stationary bulk properties have been covered in depth, much less is known about their behavior in the presence of an external shear. In this paper, we numerically study the dynamics of a bijel confined within a three-dimensional rectangular domain and subject to a symmetric shear flow sufficiently intense to break the material. Extensive numerical simulations reveal that the shear flow generally promotes the detachment of a sizable amount of particles from the fluid interface and their accumulation in the bulk. Fluid interfaces undergo large stretching and deformations along the flow direction, an effect that reduces their capability of entrapping particles. These results are supported by a series of quantitative indicators such as (i) curvature of the fluid interface, (ii) spatial distribution of the colloidal particles, and (iii) fluid flow structure within the microchannel.
Investigation of electrical properties of ZnO@Ag/EPDM composites
Authors: OuYang Benhong , Liu Zongxi , Wang Xubin , Zhang Tiandong , Zhang Changhai , Chi Qingguo
Published: September 2020

In this study, Ag conductive nanoparticles were successfully grown on ZnO semi-conductive nanosheets (abbreviated as ZnO@Ag) by combined sol–gel and liquid-phase chemical reduction methods. Both ZnO and ZnO@Ag are chosen as inorganic fillers, respectively, and EPDM is used as the matrix. The microstructures and electrical performances of the EPDM-based composites with different content of fillers have been systematically investigated. The results show that no nonlinear conductivity can be observed in pristine ethylene-propylene rubber (EPDM); however, obvious nonlinear conductivity appears in ZnO/EPDM composites with 10 wt. % ZnO. Especially, after introducing 10 wt. % ZnO@Ag into EPDM, the nonlinear conductive characteristics become much more remarkable compared with 10 wt. % ZnO/EPDM. As the content of ZnO@Ag and measured temperature increase, the threshold field strength that corresponds to nonlinear conductivity decreases gradually. Besides, the increase in conductivity accompanies a decrease in breakdown field strength. Compared to pristine EPDM (breakdown strength of 133.6 kV/mm), the breakdown field strength of 30 wt. % ZnO@Ag/EPDM reduces to 75.86 kV/mm at 30 °C and 51.36 kV/mm at 70 °C. In addition, both the dielectric constant and dielectric loss gradually increase with the increase in ZnO@Ag filling content due to the semi-conductive/conductive characteristics of fillers. As a consequence, this study provides an effective way to induce nonlinear conductivity for EPDM, and ZnO@Ag/EPDM composites may be used to homogenize the electric field and improve the performances of cable accessories.
Influence of geometric imperfections on the axially loaded composite conical shells with and without cutout
Authors: Li Zhun , Cao Yonghui , Pan Guang
Published: September 2020

The nonlinear stability analysis of a structure with initial geometric imperfections is very complex, difficult, and unsolved yet in designing. At present, there are no unified design guidelines for imperfection sensitive metal shells (spherical, cylindrical, conical, and so forth), and the study about composite shell structures is often for a specific ply parameter and therefore less adaptable. In this paper, the imperfection sensitivity analysis of orthotropic conical shells with and without cutouts under compression is investigated numerically. The eigenmode-shape imperfections and dimple-shape imperfections are introduced to conical shells with different cutout sizes. In order to find the worst imperfections that can reduce the buckling load as far as possible, an optimization framework based on the multiple perturbation load approach is developed by the present authors to search the possible positions of dimple-shape imperfections; the effectiveness of the algorithm has been proved by comparing with other conventional approaches.Mid-surface imperfections, a type of realistic imperfection, transferred from a cylinder are considered for a conical shell with a cutout at last. This work can provide a reference value for conical shell design for practical engineering applications.
Calculation of optical gain in AlGaN quantum wells for ultraviolet emission
Authors: Witzigmann Bernd , Römer Friedhard , Martens Martin , Kuhn Christian , Wernicke Tim , Kneissl Michael
Published: September 2020

Stimulated emission from AlGaN based quantum wells (QWs) emitting at ultraviolet wavelengths is investigated theoretically. Maxwell–Bloch equations in the second Born approximation are solved self-consistently with the Poisson equation. The valence band dispersion is obtained from a 6-band kp-model. For a QW emitting at around 270 nm with a thickness of 2.2 nm, an estimated FWHM of 10 meV for homogeneous broadening and an excitonic red shift of 100 meV are extracted under typical laser conditions. From a comparison to experimental data of stimulated emission, an inhomogeneous broadening energy of 39 meV FWHM is evaluated. Calculations show that high TE gain can be achieved for thin QWs around 2 nm thickness in a multiple QW arrangement or for single QWs thicker than 6 nm.
A Demonstration Handbook for Physics
Authors: Frier G. D. , Anderson F. J.
Published: September 2020

Created as a guide for high school and college physics teachers, this handbook contains hundreds of apparatus demonstrations that require only low-cost, everyday materials. The wide spectrum of topics addressed in this book makes it an excellent resource for every physics teacher’s library. This essential handbook is one of the only resources of its kind that is still in print.
Teaching About Magnetism
Authors: Reiland Robert J.
Published: September 2020

This book is a comprehensive workshop manual on teaching magnetism, listing 12 laboratory activities on a wide range of magnetism topics. It also covers demonstrations and displays, and computer applications for teaching magnetism. Sections on homework assignments, the use of technology for teaching magnetism, and physics contest events are included.

The workshop manual has been tested and improved over time following feedback from participants.

Key highlights:An invaluable resource on how to use demonstrations to inspire studentsThe workshop was initially tested in the 1993 class of PTRA-PLUS (Physics Teaching Resource Agent), a program designed to train superior physics teachers across the U.S. in giving workshops for under-prepared physics and physical science teachers.Sources of inspiration contributing to the manual include the journal of the American Association of Physics Teachers (AAPT), The Physics Teacher.

Teaching About Magnetism is an excellent resource for physics teachers. It is also of interest to anyone who works with magnetic devices, magnetic equipment, magnetic flux, magnetization dynamics, magnetochemistry, or nanomagnetism.
Synthesis of Atomically Thin CdTe Nanoplatelets by Using Polytelluride Tellurium Precursors
Authors: Wang Fei , Javaid Shaghraf , Chen Wei , Wang Aixiang , Buntine Mark A. , Jia Guohua
Published: September 2020

Colloidal two-dimensional (2D) semiconductor nanocrystals are of great importance due to their remarkable optical and electronic properties. Herein, shape-controllable synthesis of 2D wurtzite CdTe nanoplatelets (NPLs) by simply tailoring the reactivity of a tellurium (Te) precursor is reported. Ribbon-, shield-, and bullet-like 2D CdTe NPLs were prepared by a stepwise conversion from CdTe magic-size nanoclusters (MSNCs) by using Te32–, Te22–, and Te2– polytellurides as the tellurium precursor, respectively. This work not only develops a synthetic strategy capable of synthesising wurtzite CdTe nanoplatelets with controlled shapes by tailoring the reactivity of tellurium precursors but also gives insights into the growth mechanisms of colloidal 2D semiconductor nanocrystals.
Defining separation zones for coastal birds at a wetland of global importance
Authors: Reynolds Chevonne , Henry Dominic A. W. , Tye Donovan R. C. , Tye Nicholas D.
Published: September 2020

Abstract ContextThe disruption of normal activities by humans (i.e. ‘anthropogenic disturbance’) can have important behavioural, physiological and population effects on coastal birds. These negative effects include increased vigilance, increased energy expenditure and reduced nesting success. To overcome this, separation distances (e.g. buffers and setbacks) are often used to separate threatening stimuli, such as humans, from wildlife. However, in most instances the determination of separation distances are based on little empirical information. This is particularly true for Africa, which supports huge populations of Palearctic migrant shorebirds. AimTo determine suitable separation distances that will reduce anthropogenic disturbance to the coastal bird community at West Coast National Park, South Africa. MethodsThe distance at which a behavioural response (i.e. flight initiation distance, FID) occurred among 15 common coastal bird species when presented with an approaching human was measured. Linear mixed-effects models were used to determine the relationship between FID and body size, migratory status, intraspecific flock size, flock species richness, foraging behaviour and several environmental covariates. Key resultsBody mass was significantly and positively correlated with FID, indicating that larger birds are more sensitive to the anthropogenic stimulus. Furthermore, it was shown that migratory birds had longer FIDs, suggesting that they are less risk tolerant compared with resident birds. The distance at which the approach was initiated (i.e. the start distance, SD) was also significantly and positively correlated with FID, supporting the hypothesis that birds will flush early to avoid the potential negative consequences of fleeing too late. Finally, there was a novel significant effect of increasing wind speed on increasing FID, suggesting a thermoregulatory trade-off. There was no effect of foraging behaviour, flock size or flock composition on FID. ConclusionBased on these data, buffer distances for tidal habitats at West Coast National Park should be set at ~170 m. ImplicationsImproved understanding of FID, and the morphological and behavioural predictors thereof, will enable West Coast National Park and other protected areas to designate separation distances or buffer zones that reduce the negative effects of anthropogenic disturbance on shorebird communities.
The effect of negative feedback in multipoint nanosecond corona discharge
Authors: Ponizovskiy Alexander Z
Published: September 2020

The results of studies on the use of low-temperature non-equilibrium plasma for the generation of ozone (O3) in air and oxygen are presented. The results were obtained at facilities called plasma ozonators (PO), in which O3 was generated by means of a nanosecond pulsed streamer corona discharge (NCD). The NCD was created in reactor chambers consisting of coaxially arranged high-voltage multi-pointed and grounded tubular electrodes. The high-voltage electrode was supplied with a pulse voltage generated by a three-stage Fitch frequency generator. The experiments used three types of PO with a capacity of 1–6 kW. The range of pulse amplitude was 50–75 kV, of pulse front duration was 150–250 ns, of pulse duration was 300–500 ns and of pulse repetition rate was 100–1000 Hz. The air flow through the PO varied from 10 to 1500 m3 h−1. It has been established that the NCD is a system with negative feedback (NFE). The effect of NFE is that O3 production with the help of NCD leads to a sharp decrease in corona streamer currents and energy introduced into the gas. Due to the effect of NFE with increasing O3 concentration, the efficiency of its operating time in PO decreases by 3–4 times. A possible mechanism of the NFE effect, which is uniquely related to the structure of the nanosecond streamer corona, is discussed.
Spin dynamics at interfaces on femtosecond timescales
Authors: Eschenlohr A
Published: September 2020

The excitation of magnetically ordered materials with ultrashort laser pulses results in magnetization dynamics on femto- to picosecond timescales. These non-equilibrium spin dynamics have emerged as a rapidly developing research field in recent years. Unraveling the fundamental microscopic processes in the interaction of ultrashort optical pulses with the charge, spin, orbital, and lattice degrees of freedom in magnetic materials shows the potential for controlling spin dynamics on their intrinsic timescales and thereby bring spintronics applications into the femtosecond range. In particular, femtosecond spin currents offer fascinating new possibilities to manipulate magnetization in an ultrafast and non-local manner, via spin injection and spin transfer torque at the interfaces of ferromagnetic layered structures. This topical review covers recent progress on spin dynamics at interfaces on femtosecond time scales. The development of the field of ultrafast spin dynamics in ferromagnetic heterostructures will be reviewed, starting from spin currents propagating on nanometer length scales through layered structures before focusing on femtosecond spin transfer at interfaces. The properties of these ultrafast spin-dependent charge currents will be discussed, as well as the materials dependence of femtosecond spin injection, the role of the interface properties, and competing microscopic processes leading to a loss of spin polarization on sub-picosecond timescales.
Uncertainty assessment of the Ring of Fire concept for on-site aerodynamic drag evaluation
Authors: Spoelstra A , Hirsch M , Sciacchitano A , Scarano F
Published: September 2020

The Ring of Fire (RoF) measurement concept to perform on-site experiments of aerodynamic drag for transiting objects is investigated with a study that identifies the main sources of uncertainty.

The main contributors to the uncertainty of the drag measurement are examined for the case of a cyclist riding through the measurement domain. A sensitivity analysis is conducted that assesses how the estimated drag is affected by the choice of particle image velocimetry image processing parameters. The size of the cross-section considered in the control volume formulation is also investigated. It is found that the accuracy of the estimated drag depends on the procedure used to detect the edge of the momentum deficit region in the wake. Moreover imposing mass conservation yields the most accurate drag measurements. The drag estimation has little dependence upon the spatial resolution of the measurement as long as the interrogation window size stays within 5% to 25% of the equivalent diameter of the object cross section. Experiments are conducted in a sport-hall, where the aerodynamic drag estimates from the RoF are compared to a conventional torque power meter installed on the bicycle, and different rider’s postures as well as equipment variations are considered. Although the discrepancy in the absolute value of drag can be as high as 20%, power metering and RoF agree within 4% on relative drag variations.
DNA rearrangement on the octadecylamine modified graphite surface by heating and ultrasonic treatment
Authors: Xiong Xiaolu , Han Junfeng , Chen Yu , Li Shanshan , Xiao Wende , Shi Qingfan
Published: September 2020

The evolution of single-stranded DNA (ssDNA) assembly on octadecylamine (ODA) modified highly oriented pyrolytic graphite (HOPG) surface by heating and ultrasonic treatment has been studied for the first time. We have observed that DNA on the ODA coated HOPG surface underwent dramatic morphological changes as a function of heating and ultrasonic treatment. Ordered DNA firstly changed to random aggregates by heating and then changed to three-dimensional (3D) networks by ultrasonic treatment. This finding points to previously unknown factors that impact graphite–DNA interaction and opens new opportunities to control the deposition of DNA onto graphitic substrates. In this way, we built a cost-effective method to produce large-scale 3D ssDNA networks. All of these studies pave the way to understand the properties of DNA–solid interface, design novel nanomaterials, and improve the sensitivity of DNA biosensors.
Fabrication of AZ91D/Cu/Mg2Cu and AZ91D/Mg2Cu/MgCu2/MgO in-situ hybrid surface nanocomposites via friction stir processing
Authors: Farghadani Mahdie , Karimzadeh Fathollah , Enayati Mohammad Hossein , Naghshehkesh Nastaran , Ostovari Moghaddam Ahmad
Published: September 2020

In this study, in situ surface nanocomposites based on Mg-CuO and Mg-Cu systems were developed via six passes of friction stir processing (FSP) on the surface of AZ91 magnesium casting alloy. In-situ phase evolution during FSP with the addition of Cu and CuO micro-powders was studied by x-ray diffraction (XRD) analysis and microstructural investigations. Here, AZ91/Cu nanocomposite was reinforced by the in situ formation of Mg2Cu intermetallic compound. In AZ91/CuO nanocomposite, CuO particles were reduced and MgO and MgCu2 reinforcing particles alongside Mg2Cu intermetallic compounds were formed during FSP. Grain refinement and in situ formation of reinforcement particles with different sizes ranging from nano- to micro-scale significantly improved mechanical performance of the specimens. Dynamic recrystallization was found to be the main mechanism of grain refinement. After six passes of FSP, the hardness values of AZ91/Cu and AZ91/CuO nanocomposites were increased by 69.1% and 91%, respectively. Besides, AZ91/CuO nanocomposite exhibited the best tensile strength and wear resistance among all the samples. The dominant wear mechanisms were abrasive and delamination wear in AZ91 magnesium alloy, while nanocomposite specimens were worn mainly by abrasive mechanism.
Simultaneous Identification of Cell of Origin, Translocations, and Hotspot Mutations in Diffuse Large B-Cell Lymphoma Using a Single RNA-Sequencing Assay
Authors: Crotty Rory , Hu Krista , Stevenson Kristen , Pontius Maggie Y , Sohani Aliyah R , Ryan Russell J H , Rueckert Erroll , Brauer Heather A , Hudson Briana , Berlin Aaron M , Rodenbaugh Matt , Licon Abel , Haimes Josh , Iafrate A John , Nardi Valentina , Louissaint Abner
Published: September 2020

Objectives

Diffuse large B-cell lymphoma (DLBCL) is an aggressive non-Hodgkin lymphoma with a heterogenous genetic landscape that can require multiple assays to characterize. We reviewed a 1-step RNA-based assay to determine cell of origin (COO), detect translocations, and identify mutations and to assess the role of the assay in diagnosis.

Methods

Using a single custom Archer FusionPlex Lymphoma panel, we performed anchored multiplex polymerase chain reaction–based RNA sequencing on 41 cases of de novo DLBCL. Each case was subclassified by COO, and gene fusions and hotspot mutations were identified. The findings were then compared with COO classification by the Hans immunohistochemical algorithm and NanoString technology, cytogenetics, and fluorescence in situ hybridization results.

Results

Concordant COO classification by the FusionPlex panel and NanoString was observed in 35 of 41 cases (85.3%), with NanoString and Hans concordant in 33 of 41 cases (80.5%) and FusionPlex and Hans concordant in 33 of 41 cases (80.5%). The FusionPlex assay also detected 6 of 11 BCL6 translocations (4 cryptic), 2 of 3 BCL2 translocations, and 2 of 4 MYC translocations. Mutations were detected in lymphoma-related genes in 24 of 41 cases.

Conclusion

This FusionPlex assay offers a single method for COO classification, mutation detection, and identification of important translocations in DLBCL. Although not replacing traditional testing, it could offer useful data when limited tissue is available
Characteristics Associated With Nonreceipt of Surveillance Testing and the Relationship With Survival in Stage II and III Colon Cancer
Authors: Hines Robert B , Jiban Md Jibanul Haque , Lee Eunkyung , Odahowski Cassie L , Wallace Audrey S , Adams Spencer J E , Rahman Saleh M M , Zhang Shunpu
Published: September 2020

We investigated characteristics of patients with colon cancer that predicted nonreceipt of posttreatment surveillance testing and the subsequent associations between surveillance status and survival outcomes. This was a retrospective cohort study of the Surveillance, Epidemiology, and End Results database combined with Medicare claims. Patients diagnosed between 2002 and 2009 with disease stages II and III and who were between 66 and 84 years of age were eligible. A minimum of 3 years’ follow-up was required, and patients were categorized as having received any surveillance testing (any testing) versus none (no testing). Poisson regression was used to obtain risk ratios with 95% confidence intervals for the relative likelihood of No Testing. Cox models were used to obtain subdistribution hazard ratios with 95% confidence intervals for 5- and 10-year cancer-specific and noncancer deaths. There were 16,009 colon cancer cases analyzed. Patient characteristics that predicted No Testing included older age, Black race, stage III disease, and chemotherapy. Patients in the No Testing group had an increased rate of 10-year cancer death that was greater for patients with stage III disease (subdistribution hazard ratio = 1.79, 95% confidence interval: 1.48, 2.17) than those with stage II disease (subdistribution hazard ratio = 1.41, 95% confidence interval: 1.19, 1.66). Greater efforts are needed to ensure all patients receive the highest quality medical care after diagnosis of colon cancer.
Metabolic and behavioral adaptations of greater white-toothed shrews to urban conditions
Authors: Oliveira Flávio G , Mathias Maria da Luz , Rychlik Leszek , Tapisso Joaquim T , von Merten Sophie
Published: September 2020

The global trend of urbanization is creating novel challenges for many animal species. Studies investigating behavioral differences between rural and urban populations often report a general increase in risk-taking behaviors in urban populations. According to the most common energy management model (the performance model), behaviors that increase access to resources, such as aggression and boldness, and behaviors that consume net energy, like locomotion and stress responses, are both positively correlated to resting metabolic rate (RMR). Thus, we expect urban populations to not only exhibit a higher level of risk-taking behavior but also a higher RMR. However, these interactions remain poorly investigated. Our main goal was to analyze the relationship between RMR and risk-taking behaviors in the greater white-toothed shrew (Crocidura russula) in rural versus urban populations. Trapped shrews were brought to captivity where we measured RMR, boldness, and exploration rate three times in each individual. Our findings revealed that urban shrews were indeed bolder and more exploratory, but contrary to our expectations, their RMR was lower than that of rural shrews. This is likely explained by differences in the environmental conditions of these two habitats, such as higher ambient temperatures and/or lower prey availability in cities. When looking at each population separately, this relationship remained similar: urban shrews with a higher RMR were less bold, and rural shrews with a higher RMR showed a lower exploration rate. We conclude that the energetic strategy of C. russula is dependent on the environmental and observational context and cannot be explained by the performance model.
A Double-blind, Randomized Trial to Evaluate Miltefosine and Topical Granulocyte Macrophage Colony-stimulating Factor in the Treatment of Cutaneous Leishmaniasis Caused by Leishmania braziliensis in Brazil
Authors: Machado Paulo R L , Prates Fernanda V O , Boaventura Viviane , Lago Tainã , Guimarães Luiz H , Schriefer Albert , Corte Temis W F , Penna Gerson , Barral Aldina , Barral-Netto Manoel , Carvalho Edgar M
Published: September 2020

Background

The treatment of cutaneous leishmaniasis (CL) in Brazil using pentavalent antimony (Sbv) is associated with a high rate of failure. Miltefosine has proven efficacy for CL caused by L. braziliensis, with a cure rate (CR) of 75%. A combined treatment with granulocyte macrophage colony-stimulating factor (GM-CSF) and miltefosine could increase CR and decrease healing time.

Methods

A randomized, double-blind clinical trial to evaluate the efficacy of miltefosine combined with topical GM-CSF (M + GM) vs miltefosine and placebo (M + P) vs Sbv in 133 patients with CL caused by L. braziliensis in Bahia, Brazil.

Results

The final CR at 180 days after the initiation of treatment was 44.4% in the Sbv group, 76.6% in the M + P group (P = .003 vs Sbv), and 75.6% in the M + GM group (P = .004 vs Sbv). The median healing time for cure was 102 days for the Sbv group and 60 days for both miltefosine groups (P = .0009). During the 6-month follow-up period, 4 relapses were documented: 1 in the Sbv group, 1 in the M + P group, and 2 in the M + GM group. Mild adverse events occurred in 65% of patients from the Sbv group, 76% and 79% from the M + P and M + GM groups respectively.

Conclusions

Miltefosine is more effective than Sbv for the treatment of CL caused by L. braziliensis in Brazil and accelerates the healing time. Association with GM-CSF does not improve therapeutic outcome.

Clinical Trials Registration

NCT03023111.
Economic Evaluation of Screening Interventions for Drug-induced Liver Injury
Authors: Moed Saundria , Suprenant Mark , Odjidja Emmanuel Nene , Meguid Tarek , Zaman Muhammad H
Published: September 2020

Background

Human immunodeficiency virus (HIV)/AIDS and tuberculosis (TB) continue to be a significant global burden, disproportionately affecting low- and middle-income countries (LMICs). While much progress has been made in treating these epidemics, this has led to a rise in liver complications, as patients on ARTs and anti-TBs are at an increased risk of drug-induced liver injury (DILI). Therefore, patients on these medicines require consistent screening of liver function. Due to logistical barriers, gold standard DILI screening fails to be executed at the point-of-care in LMICs. For this reason, we used cost-effectiveness analysis to gauge the efficacy of a paper-test that could be implemented in these settings.

Methods

We used a Markov Model to simulate HIV and TB coinfected patient care in LMICs using both publicly available data and data from Village Health Works in Burundi. We compared the cost-effectiveness of two screening interventions for liver function monitoring: 1. paper-based point-of-care testing, and 2. gold-standard laboratory testing. These interventions were compared against baseline clinical monitoring.

Results

The paper test showed a 56% increase in efficacy over clinical monitoring alone. The paper-test is more cost-effective than the gold-standard method, at a ceiling cost of $1.60 per test.

Conclusions

With this information, policy makers can be informed as to the large potential value of paper-based tests when gold standard monitoring is not achievable. Scientists and engineers should also keep these analyses in mind and while in development limit the cost of an ALT screening test to $1.60.
Color Data v2: a user-friendly, open-access database with hereditary cancer and hereditary cardiovascular conditions datasets
Authors: Berger Mark J , Williams Hannah E , Barrett Ryan , Zimmer Anjali D , McKennon Wendy , Hong Huy , Ginsberg Jeremy , Zhou Alicia Y , Neben Cynthia L
Published: September 2020

Publicly available genetic databases promote data sharing and fuel scientific discoveries for the prevention, treatment and management of disease. In 2018, we built Color Data, a user-friendly, open access database containing genotypic and self-reported phenotypic information from 50 000 individuals who were sequenced for 30 genes associated with hereditary cancer. In a continued effort to promote access to these types of data, we launched Color Data v2, an updated version of the Color Data database. This new release includes additional clinical genetic testing results from more than 18 000 individuals who were sequenced for 30 genes associated with hereditary cardiovascular conditions as well as polygenic risk scores for breast cancer, coronary artery disease and atrial fibrillation. In addition, we used self-reported phenotypic information to implement the following four clinical risk models: Gail Model for 5-year risk of breast cancer, Claus Model for lifetime risk of breast cancer, simple office-based Framingham Coronary Heart Disease Risk Score for 10-year risk of coronary heart disease and CHARGE-AF simple score for 5-year risk of atrial fibrillation. These new features and capabilities are highlighted through two sample queries in the database. We hope that the broad dissemination of these data will help researchers continue to explore genotype–phenotype correlations and identify novel variants for functional analysis, enabling scientific discoveries in the field of population genomics.

Database URL: https://data.color.com/
PRECISE-DAPT score for bleeding risk prediction in patients on dual or single antiplatelet regimens: insights from the GLOBAL LEADERS and GLASSY
Authors: Gragnano Felice , Heg Dik , Franzone Anna , McFadden Eugène P , Leonardi Sergio , Piccolo Raffaele , Vranckx Pascal , Branca Mattia , Serruys Patrick W , Benit Edouard , Liebetrau Christoph , Janssens Luc , Ferrario Maurizio , Zurakowski Aleksander , Diletti Roberto , Dominici Marcello , Huber Kurt , Slagboom Ton , Buszman Paweł , Bolognese Leonardo , Tumscitz Carlo , Bryniarski Krzysztof , Aminian Adel , Vrolix Mathias , Petrov Ivo , Garg Scot , Naber Christoph , Prokopczuk Janusz , Hamm Christian , Steg Philippe Gabriel , Jüni Peter , Windecker Stephan , Valgimigli Marco
Published: September 2020

Aims

The five-item PRECISE-DAPT, integrating age, haemoglobin, white-blood-cell count, creatinine clearance, and prior bleeding, predicts bleeding risk in patients on dual antiplatelet therapy (DAPT) after stent implantation. We sought to assess whether the bleeding risk prediction offered by the PRECISE-DAPT remains valid among patients receiving ticagrelor monotherapy from 1 month onwards after coronary stenting instead of standard DAPT and having or not having centrally adjudicated bleeding endpoints.

Methods and results

The PRECISE-DAPT was calculated in 14 928 and 7134 patients from GLOBAL LEADERS and GLASSY trials, respectively. The ability of the score to predict Bleeding Academic Research Consortium 3 or 5 bleeding was assessed and compared among patients on ticagrelor monotherapy (experimental strategy) or standard DAPT (reference strategy) from 1 month after drug-eluting stent implantation. Bleeding endpoints were investigator-reported or centrally adjudicated in GLOBAL LEADERS and GLASSY, respectively. At 2 years, the c-indexes for the score among patients treated with the experimental or reference strategy were 0.67 [95% confidence interval (CI): 0.63–0.71] vs. 0.63 (95% CI: 0.59–0.67) in GLOBAL LEADERS (P = 0.27), and 0.67 (95% CI: 0.61–0.73) vs. 0.66 (95% CI: 0.61–0.72) in GLASSY (P = 0.88). Decision curve analysis showed net benefit using the PRECISE-DAPT to guide bleeding risk assessment under both treatment strategies. Results were consistent between investigator-reported and adjudicated endpoints and using the simplified four-item PRECISE-DAPT.

Conclusion

The PRECISE-DAPT offers a prediction model that proved similarly effective to predict clinically relevant bleeding among patients on ticagrelor monotherapy from 1 month after coronary stenting compared with standard DAPT and appears to be unaffected by the presence or absence of adjudicated bleeding endpoints.
mHealth adoption among primary care physicians in Malaysia and its associated factors: a cross-sectional study
Authors: Lim Hooi Min , Dunn Adam G , Muhammad Firdaus Ooi Sakinah , Teo Chin Hai , Abdullah Adina , Woo Wing Jun , Ng Chirk Jenn
Published: September 2020

Background

mHealth apps potentially improve health care delivery and patient outcomes, but the uptake of mHealth in primary care is challenging, especially in low–middle-income countries.

Objective

To measure factors associated with mHealth adoption among primary care physicians (PCPs) in Malaysia.

Methods

A cross-sectional study using a self-administered questionnaire was conducted among PCPs. The usage of mHealth apps by the PCPs has divided into the use of mHealth apps to support PCPs’ clinical work and recommendation of mHealth apps for patient’s use. Factors associated with mHealth adoption were analysed using multivariable logistic regression.

Results

Among 217 PCPs in the study, 77.0% used mHealth apps frequently for medical references, 78.3% medical calculation and 30.9% interacting with electronic health records (EHRs). Only 22.1% of PCPs frequently recommended mHealth apps to patients for tracking health information, 22.1% patient education and 14.3% use as a medical device. Performance expectancy and facilitating conditions were associated with mHealth use for medical references. Family medicine trainees, working in a government practice and performance expectancy were the facilitators for the use of mHealth apps for medical calculation. Internet connectivity, performance expectancy and use by colleagues were associated with the use of mHealth with EHR. Performance expectancy was associated with mHealth apps’ recommendation to patients to track health information and provide patient education.

Conclusions

PCPs often used mHealth apps to support their clinical work but seldom recommended mHealth apps to their patients. Training for PCPs is needed on the appraisal and knowledge of the mHealth apps for patient use.
Uptake, recognition and responses to peptidoglycan in the mammalian host
Authors: Bastos Paulo A D , Wheeler Richard , Boneca Ivo G
Published: September 2020

Microbiota, and the plethora of signalling molecules that they generate, are a major driving force that underlies a striking range of inter-individual physioanatomic and behavioural consequences for the host organism. Among the bacterial effectors, one finds peptidoglycan, the major constituent of the bacterial cell surface. In the steady-state, fragments of peptidoglycan are constitutively liberated from bacterial members of the gut microbiota, cross the gut epithelial barrier and enter the host system. The fate of these peptidoglycan fragments, and the outcome for the host, depends on the molecular nature of the peptidoglycan, as well the cellular profile of the recipient tissue, mechanism of cell entry, the expression of specific processing and recognition mechanisms by the cell, and the local immune context. At the target level, physiological processes modulated by peptidoglycan are extremely diverse, ranging from immune activation to small molecule metabolism, autophagy and apoptosis. In this review, we bring together a fragmented body of literature on the kinetics and dynamics of peptidoglycan interactions with the mammalian host, explaining how peptidoglycan functions as a signalling molecule in the host under physiological conditions, how it disseminates within the host, and the cellular responses to peptidoglycan.
Evaluating implementation strategies for essential newborn care interventions in low- and low middle-income countries: a systematic review
Authors: Peven Kimberly , Bick Debra , Purssell Edward , Rotevatn Torill Alise , Nielsen Jane Hyldgaard , Taylor Cath
Published: September 2020

Neonatal mortality remains a significant health problem in low-income settings. Low-cost essential newborn care (ENC) interventions with proven efficacy and cost-effectiveness exist but have not reached high coverage (≥90%). Little is known about the strategies used to implement these interventions or how they relate to improved coverage. We conducted a systematic review of implementation strategies and implementation outcomes for ENC in low- and low middle-income countries capturing evidence from five medical and global health databases from 1990 to 2018. We included studies of implementation of delayed cord clamping, immediate drying, skin-to-skin contact (SSC) and/or early initiation of breastfeeding implemented in the first hour (facility-based studies) or the 1st day (community-based studies) of life. Implementation strategies and outcomes were categorized according to published frameworks: Expert Recommendations for Implementing Change and Outcomes for Implementation Research. The relationship between implementation strategies and outcomes was evaluated using standardized mean differences and correlation coefficients. Forty-three papers met inclusion criteria. Interventions included community-based care/health promotion and facility-based support and health care provider training. Included studies used 3–31 implementation strategies, though the consistency with which strategies were applied was variable. Conduct educational meetings was the most frequently used strategy. Included studies reported 1–4 implementation outcomes with coverage reported most frequently. Heterogeneity was high and no statistically significant association was found between the number of implementation strategies used and coverage of ENC. This review highlights several challenges in learning from implementation of ENC in low- and low middle-income countries, particularly poor description of interventions and implementation outcomes. We recommend use of UK Medical Research Council guidelines (2015) for process evaluations and checklists for reporting implementation studies. Improved reporting of implementation research in this setting is necessary to learn how to improve service delivery and outcomes and thereby reduce neonatal mortality.
Filling the gaps in the characterization of the clinical management of COVID-19: 30-day hospital admission and fatality rates in a cohort of 118 150 cases diagnosed in outpatient settings in Spain
Authors: Prieto-Alhambra Daniel , Balló Elisabet , Coma Ermengol , Mora Núria , Aragón María , Prats-Uribe Albert , Fina Francesc , Benítez Mència , Guiriguet Carolina , Fàbregas Mireia , Medina-Peralta Manuel , Duarte-Salles Talita
Published: September 2020

Background

Currently, there is a missing link in the natural history of COVID-19, from first (usually milder) symptoms to hospitalization and/or death. To fill in this gap, we characterized COVID-19 patients at the time at which they were diagnosed in outpatient settings and estimated 30-day hospital admission and fatality rates.

Methods

This was a population-based cohort study.

 

Data were obtained from Information System for Research in Primary Care (SIDIAP)—a primary-care records database covering >6 million people (>80% of the population of Catalonia), linked to COVID-19 reverse transcriptase polymerase chain reaction (RT-PCR) tests and hospital emergency, inpatient and mortality registers. We included all patients in the database who were ≥15 years old and diagnosed with COVID-19 in outpatient settings between 15 March and 24 April 2020 (10 April for outcome studies). Baseline characteristics included socio-demographics, co-morbidity and previous drug use at the time of diagnosis, and polymerase chain reaction (PCR) testing and results.

 

Study outcomes included 30-day hospitalization for COVID-19 and all-cause fatality.

Results

We identified 118 150 and 95 467 COVID-19 patients for characterization and outcome studies, respectively. Most were women (58.7%) and young-to-middle-aged (e.g. 21.1% were 45–54 years old). Of the 44 575 who were tested with PCR, 32 723 (73.4%) tested positive. In the month after diagnosis, 14.8% (14.6–15.0) were hospitalized, with a greater proportion of men and older people, peaking at age 75–84 years. Thirty-day fatality was 3.5% (95% confidence interval: 3.4% to 3.6%), higher in men, increasing with age and highest in those residing in nursing homes [24.5% (23.4% to 25.6%)].

Conclusion

COVID-19 infections were widespread in the community, including all age–sex strata. However, severe forms of the disease clustered in older men and nursing-home residents. Although initially managed in outpatient settings, 15% of cases required hospitalization and 4% died within a month of first symptoms. These data are instrumental for designing deconfinement strategies and will inform healthcare planning and hospital-bed allocation in current and future COVID-19 outbreaks.
Exponential stabilization of an ODE–linear KdV cascaded system with boundary input delay
Authors: Ayadi Habib
Published: September 2020

This paper considers the well posedness and the exponential stabilization problems of a cascaded ordinary differential equation (ODE)–partial differential equation (PDE) system. The considered system is governed by a linear ODE and the one-dimensional linear Korteweg–de Vries (KdV) equation posed on a bounded interval. For the whole system, a control input delay acts on the left boundary of the KdV domain by Dirichlet condition. Whereas, the KdV acts back on the ODE by Dirichlet interconnection on the right boundary. Firstly, we reformulate the system in question as an undelayed ODE-coupled KdV-transport system. Secondly, we use the so-called infinite dimensional backstepping method to derive an explicit feedback control law that transforms system under consideration to a well-posed and exponentially stable target system. Finally, by invertibility of such design, we use semigroup theory and Lyapunov analysis to prove the well posedness and the exponential stabilization in a suitable functional space of the original plant, respectively.
Relative Trace Formula for Compact Quotient and Pseudo-Coefficients for Relative Discrete Series
Authors: Delorme Patrick , Harinck Pascale
Published: September 2020

We introduce the notion of relative pseudo-coefficient for relative discrete series representations of real spherical homogeneous spaces of reductive groups. We prove that $K$-finite relative pseudo-coefficient does not exist for semisimple symmetric spaces of type $G_{\mathbb{C}}/G_{\mathbb{R}}$, where $K$ is a maximal compact subgroup of $G_{\mathbb{C}}$, and construct strong relative pseudo-coefficients for some hyperbolic spaces. We establish a toy model for the relative trace formula of H. Jacquet for compact discrete quotient $\Gamma \backslash G$. This allows us to prove that a relative discrete series representation, which admits strong pseudo-coefficients with sufficiently small support, occurs in the spectral decomposition of $L^2(\Gamma \backslash G)$ with a nonzero period.
Setting the stage for a Global Programme to Eliminate Lymphatic Filariasis: the first 125 years (1875–2000)
Authors: Ottesen Eric A , Horton John
Published: September 2020

The development of the World Health Organization's Global Programme to Eliminate Lymphatic Filariasis (GPELF) can be interpreted through many different lenses—e.g. one focusing on the health or economic plight of affected individuals and populations, another tracking the individuals and organizations responsible for building the programme or, as in this review, one identifying each of the critical requirements and specific hurdles that need to be addressed in order to successfully construct the programme. For almost 75 y after the life cycle of LF was first described, the principal tool for countering it was vector control. Discovery that diethylcarbamazine (and later ivermectin and albendazole) could effectively treat affected and at-risk populations, along with the availability of a simple, field-based diagnostic test to monitor programme progress, provided the essential tools for LF elimination. Recognition of this potential by the global health community (including the World Health Assembly) led two pharmaceutical companies (GlaxoSmithKline and MSD (Merck & Co. Inc., Kenilworth, NJ, USA) to make enormous, unprecedented donations of albendazole and ivermectin to achieve this goal. Additional resource support from the public and private sectors and from health ministries in the 80 LF-endemic countries led to the creation of a Global Alliance to Eliminate LF, which launched the GPELF in 2000, just 125 y after the LF life cycle was first described.
A comparative analysis of cervical cancer prevention between Nigeria and Nordic countries that have experienced a decline in cervical cancer incidence
Authors: Anyasi Helen I , Foss Anna M
Published: September 2020

Background

A modelling analysis carried out in 2014 suggested that, without cervical cancer screening programmes, the incidence of cervical cancer in Denmark, Finland, Norway and Sweden would have been as high as that in some low- and middle-income countries. We compare programme strategies between Nigeria and these Nordic countries and develop translatable recommendations.

Methods

A literature review using a systematic approach through Medline, Popline, Global Health, CINAHL PLUS, Cochrane Library, EMBASE, Google Scholar, Africa Wide and WHO databases was conducted.

Results

Fifteen journal articles and two grey literature reports met our criteria. Six descriptive studies from Nigeria noted that services in Nigeria were mainly provided in urban secondary/tertiary facilities and that uptake was low even where screening was free. Trials in Nigeria and Sweden noted that subsidies and free programmes alone did not improve uptake; a Danish trial demonstrated that reminders and invitations issued by general practitioners improved participation.

Conclusion

Free screening programmes are important but should also consider incentivisation of treatment when needed and demand creation among health workers. Additionally, effective monitoring and evaluation of programme data are key to improving and maintaining quality. More broadly, we suggest that Nigeria can build success through stakeholder-led implementation of well-defined policies with national consensus to ensure coordination and sustainability.
Global Club Goods and the Fragmented Global Financial Safety Net
Authors: Gavin Michael A
Published: September 2020

It is generally regarded that a robust global financial safety net is a global public good. Yet public goods models that explain the existence of the global financial safety net cannot also explain why it is highly fragmented and provisioned so inequitably. This study shows that the global financial safety net's existence, fragmentation, and inequitable coverage can be explained by modeling the global financial safety net as a global club good. The primary finding of the model is that when a state has a monopoly on the provision of a non-rival and excludable good (i.e., a club good), separate multilateral and bilateral club governance structures emerge, each with a unique structure and cost. Brief case studies of the global financial safety net provisioned by the International Monetary Fund, the Federal Reserve, and the Bank for International Settlements support the model.