bluuebunny/crossref_metadata_2025 huggingface dataset:
Methods for Evaluating the Effectiveness of Gas Vortex Stabilization in Plasma Torches for Metal Cutting
Authors: Yu Matushkina I , Anakhov S V , Pyckin Yu A
Published: November 2020

The well-known recommendations for the design of gas-vortex stabilization systems in metal-cutting plasma torches are considered. Various designs of such systems used in the series PMVR plasma torches developed by the authors are presented. It is noted that the method of efficiency assessment developed by the authors should be based on the calculation of the uniformity distribution of the gas flow velocity. The velocities are calculated in the control sections of the gas-air path in the plasma torch. Various simplified and precise estimation methods are proposed. The velocity distribution in control sections for various modifications of plasma torches are presented. Calculations are made based on the “cold” model of gas flow and its heating by a plasma arc. Recommendations are made on the choice of parameters for evaluating the effectiveness of gas-vortex stabilization in plasma torches. The advantages of the new modernized plasma torches, including those using narrow-jet plasma technology, in terms of the gas-vortex stabilization efficiency are demonstrated. The necessity of using several criteria for evaluating the effectiveness of plasma torches design is noted.
Features of Technogenic Iron Oxide Recovery
Authors: Yu Sheshukov O , Mikheenkov M M , Vedmid L B
Published: November 2020

The overview of existing models for iron oxides reducing and an analysis of their applicability to technogenic formations is presented. The thermodynamic analysis data of iron oxides reducing reactions through solid and gas phases and experiment results presenting features of technogenic iron oxide reducing under conditions of solid-phase diffusion (limited diffusion) and partially liquid-phase diffusion (easier diffusion) of iron oxide ions. It is shown that under conditions of iron oxide ions solid-phase diffusion the reduction processes rate is significantly affected by the briquetting pressure, which increases the contact area of reacting substances. The briquetting pressure does not affect the reduction processes rate under conditions of partially liquid-phase diffusion of iron oxide ions. An ion-diffusion catalytic mechanism is proposed to describe the observed effects of technogenic iron oxide reducing.
Modeling Dynamic Parameters of Hard Alloys during Shock Wave Regeneration
Authors: Savchenko I , Shapoval A , Gurenko A
Published: November 2020

Construction of the shock adiabat of a porous multi-component mixture and the parameters of compression of this medium by shock waves. As a research technique for the present work, we considered the description of a solid by the equations of hydrodynamics when a shock wave propagates through a substance or mixture of substances when the shock compression pressure exceeds the yield strength of the medium components. When shockwave compression of solids is determined, the parameters of the medium during its multiple compression using the equations of state of multicomponent systems, which are represented by continuous analytical dependencies. The fundamental possibility of using shock-wave processing as a factor stimulating the processes of destruction of powder products of any configuration to obtain high-quality powder for further formation, sintering, and production of tools for various purposes is shown, using developed dependencies. Technology for the regeneration of hard alloys is developed, an environmentally friendly processing technology is proposed super hard materials, cermet components of obsolete military equipment, and different types of ammunition.
Evaluating the Range of Applicability of Existing Models of Stress Distribution in the Neck Forming on Cylindrical Specimens during Tensile Testing
Authors: Erpalov M V
Published: November 2020

This paper is devoted to the post-processing the results of testing the cylindrical specimens for tension. The tensile test are considered from the point of view of studying the rheological properties of metals and alloys. The main problem in identifying hardening curves from tensile test results is the formation of a neck, inside which the stress state of the material differs from uniaxial. The paper considers theoretical solutions to the problem of stress distribution in the neck region, namely, the models of Bridgman, Davidenkov-Spiridonova and Ostsemin. These models make it possible to calculate equivalent stress values even after specimen deformation localizes in the neck. Using the finite element method, the range of applicability of these models was evaluated. It was shown in the paper that the Ostsemin stress distribution model allows to achieve the best results of the material hardening curves identification regardless of its rheological properties. However, the range of applicability of this model is limited by the maximum strain value of 1.5-2.0. With further deformation of the specimen, an overestimation of the calculated values of equivalent stresses with respect to the proper values is observed.
The Structure of Annealed Hafnium Bronze Subjected to Severe Plastic Deformation by High Pressure Torsion
Authors: Stolbovsky A , Popov V , Falahutdinov R
Published: November 2020

The structure and mechanical properties of low-alloyed hafnium bronze (Cu-0.78 wt. % Hf) under severe plastic deformation by high-pressure torsion (HPT) by 1, 3 and 5 revolutions of anvils at room temperature have been studied by electron microscopy and microhardness measurements. In the initial annealed state Hf is practically completely bonded in intermetallic compounds. The structure of bronze specimens deformed by HPT is stable and does not undergo any changes after unloading and long room temperature ageing. Under the deformation a dispersed submicrocrystalline structure gradient along specimen radius is formed. Average crystallite size in the radius middle is 200 nm after 1 revolution and 120 nm after 5 revolutions of anvils. It is demonstrated that in all the specimens studied including those deformed by 5 revolutions the structure is not uniform which is confirmed by microhardness measurements. Such behavior of hafnium bronze with Hf bonded in precipitates has much in common with the behavior of pure copper. However, the room temperature stability of the structures obtained by HPT demonstrates similar behavior with that of low-alloyed tin bronze.
Deformation Cone of Pilger Rolling for Forward and Reverse Motion
Authors: Koval G I , Karimova T G
Published: November 2020

Two mutually perpendicular pairs of rolls show the distinctive features of the existing pilger rolling processes from the pilger rolling process developed at SUSU. The peripheral velocity vectors of them are placed in different directions from the transition zone formation position from the initial billet to the finished profile (deformation cone). The change in the deformation cone shape with the billet free ends during the pilger rolling process by two mutually perpendicular pairs of rolls, circumferential velocity vectors placed in different directions, are considered. It is accepted that during forward rolling, the billet feed is equal to m, and during reverse rolling it is equal to mλ to ensure equality of displaceable feed volumes when describing the changes sequence in the deformation cone parameters. The gradual supply volumes flattening with a forward and reverse stroke to design values is shown. This was obtained by considering several cycles of pilger rolling by sequentially increasing the feed volumes during reverse rolling and reducing the feed volumes during forward rolling.
An Investigation of the Laser Welding Process for Dual-Phase Steel via Regression Analysis
Authors: Zhao Dawei , Ivanov Mikhail , Wang Yuanxun
Published: November 2020

Abstract In this work, a systematic investigation was undertaken to explore the effects of welding process parameters on the mechanical performances of the welding joints in the laser welding process for DP600. Welding experiments were arranged by a uniform experimental design method with four control factors (laser power, welding speed, focal point position, and side-blowing shield gas flow). The tensile strength of the welding joints was used to quantify the welding quality. A mathematical model based on stepwise regression analysis was employed to correlate the welding process parameters and the tensile strength. The effects of the welding process parameters on the welding quality were discussed. The genetic algorithm was then employed to select the optimum welding parameters. The verification test results proved that the method proposed in this paper could effectively evaluate and optimize the welding quality within the range of process parameters, which could enhance the welding performance in the laser welding process as feasibly and effectively as possible.
Dependence of Weld Penetration Shape on Energy Efficiency in Electron Beam Welding Process
Authors: Goncharov A L , Sliva A P , Kharitonov I A
Published: November 2020

Investigation of relation between parameters of weld penetration shape and energy efficiency of electron beam welding process was performed in the paper. Analysis of welds cross sections of 316 L(N) steel weld joints obtained by the electron beam welding in the wide range of welding regimes is carried out. It is shown that the dependences of the thermal efficiency on the penetration area at different welding speeds are linear. According to the results, the thermal efficiency coefficient may exceed the ultimate theoretical value for linear heat source. Beam sweep does not affect essentially on the rate of thermal efficiency coefficient, since sweep application leads to an insignificant change in the area of the boundary of the weld pool with the base metal, and therefore, the amount of energy removed through this boundary also changes insignificantly and the penetration area remains almost constant.
Effect of Temperature Field on Mechanical Properties of Direct Laser Deposited Ti-6Al-4V Alloy
Authors: Gushchina M O , Yu Ivanov S , Vildanov A M
Published: November 2020

The mechanical and service properties of Ti-6Al-4V alloy parts produced by direct laser deposition (DLD) depend on the thermal cycle parameters. The temperature field during deposition is significantly affected not only by the parameters of the process, but also by the interpass dwell time and length of the deposited layers. The aim of the article is to establish the relationship between mechanical properties of deposited Ti-6Al-4V samples and DLD thermal cycle parameters. Numerical simulation was used in order to establish relationship between temperature field parameter and the process parameters. The nonlinear three-dimensional heat conduction problem was solved by the finite element method. It is shown that an increase in the dwell time between passes from 5 to 10 seconds leads to a significant decrease in the inter-pass temperature and an increase in the cooling rate. This leads to the metastable structure formation of the deposited layers of Ti-6Al-4V that consists mainly of a nonequilibrium a’-phase which hardness is higher than 390 HV. Without dwell time an equilibrium a + (3 structure with hardness of 360 HV and higher elongation is formed.
Cold Spray Deposition of Copper/Tungsten Composite Coatings
Authors: Doubenskaia M , Latfulina Yu S , Samodurova M N
Published: November 2020

This work is devoted to the study of the microstructure and the properties of the Cu-W composite coatings deposited using cold spray technology. This process allows fabrication of high-quality coatings on large surfaces of different types of materials. The technology is widely used and investigated due to technological simplicity, wide range of sprayed materials and operating temperatures. However, there are some technological problems which appear when materials with low melting temperatures are sprayed. During softening, the particles adhere to the nozzle walls and block spraying. By the way, it is possible to solve the problem adding some ceramics particles to the spraying mixture of powders. As a result, the formed coating will have better mechanical properties and the technological problem will be solved. The analysis of the general results of the microstructure studies and experiments, and comparison with other coating methods are given. Moreover, the experimental procedure of samples preparation and used equipment are given. It is shown the microstructure before and after heat treatment of the samples sprayed, microhardness measurements, thermal conductivity measurements.
Improving the Performance Characteristics of the Drawing Machine Intermediate Block Working Surface by Additive Technologies
Authors: Radionova L V , Samodurova M N , Chaplygin B A
Published: November 2020

This paper presents the study results of the drawing machine intermediate block surface hardening treatment by the methods of additive technologies. Laser surfacing of powder material Fe-4,5Cr-4,5Mo-5,5 W-4V on the intermediate block working surface a wear-resistant layer with a hardness of 52-54 HRC with a thickness of more than 1.5 mm. The laser complex LaserClad 4 C R120 based on the industrial robotic manipulator KUKA KR-120 together with the positioner is able to melt powder material only on the working surface of the intermediate block, thereby significantly reducing its cost and labor intensity during its manufacture. The applying of detonation spraying with subsequent penetration for this type of product proved to be ineffective. The detonation coating itself with a powder material based on tungsten carbide turned out to be uniform and had a hardness in the range of 61 -65 HRC. But rather large pores and cracks appeared in it after penetration, which is associated with a significant difference in the coefficients of thermal linear expansion of steel 41Cr4 (14-10-6 1/K) and an alloy based on tungsten carbide (3,9-10-6 1/K).
The study of visible-light photocatalytic degradation activity of Ag doped g-C3N4 obtained by heating process
Authors: Liu Xiao , Tang Ru-Yi , Xia Xue-Min , Qin Yao-Yu , Zhang Xia
Published: November 2020

In this paper, Ag nanoparticles (Ag NPs) were loaded on pure g-C3N4 (CN) via two different methods of direct heating and indirect heating to form g-C3N4/Ag-DX and g-C3N4/Ag-IDX photocatalysts, respectively. Using methylene blue as the degradation dye, the photocatalytic performance of g-C3N4/Ag-DX and g-C3N4/Ag-IDX was studied through visible light photocatalysis experiments. The results demonstrated that the photocatalytic performance of g-C3N4/Ag-DX and g-C3N4/Ag-IDX both increases with the increase in content of Ag nanoparticles. It is obvious that g-C3N4/Ag-ID8 has the optimal photocatalytic activity. Meanwhile, the g-C3N4/Ag-ID8 has excellent stability and can be reused in photocatalysis experiments.
Fabrication and mechanical characterization of YAG ceramic-composite with alumina nanoparticles using slip casting and sintering process
Authors: Torki M , Movahedi B , Ghazanfari S , Milani M
Published: November 2020

The aim of this study was to fabricate a YAG/Al2O3 ceramic composite with different alumina nanoparticles using slip casting and the atmospheric sintering process. In addition, some mechanical properties such as hardness and elastic modules of this ceramic were evaluated using the nanoindention technique. The results showed that the rheological behavior of the slurry was optimized to the solid loading of 55 wt%; also, the relative density of the green body was enhanced up to 65%. Relative density was increased to 99.5% after sintering at 1700 °C for 12 h; further, the pore size (150 nm) was reduced to half of that of powder particles. It should be, however, noted that the optimum amount of alumina nanoparticles as a reinforcing agent in the matrix was less than 5%wt and the composite hardness was increased to 7.3%, as compared to the pure YAG ceramic.
Thermal behavior and combustion performance of Al/MoO3 nanothermites with addition of poly (vinylidene fluorine) using electrospraying
Authors: Chen Jialin , Guo Tao , Yao Miao , Song Jiaxing , Ding Wen , Mao Yiming , Li Shi , Zhu Rui
Published: November 2020

To investigate the effect of the addition of poly (vinylidene fluoride) (PVDF) on nanothermites, Al/MoO3/PVDF energetic nanocomposites were prepared using electrospraying method. As a control group, Al/MoO3 was also designed. Then, both samples were tested by FE-SEM, XRD and TG-DSC. TG-DSC results showed that the Al/MoO3/PVDF energetic nanocomposites released more than 934.0 J g−1 with two obvious exothermic peaks. Compared with the control group of 800.7 J g−1 heat, it changed the thermal performance to some extent. There were Mo2C among the residues products after the reaction via XRD. The activation energy (Ea) was analyzed using the Kissinger method under different heating rates by DSC. The addition of PVDF reduced the Ea of the thermites. To explore the combustion performance, a preliminary experiment was designed. The Al/MoO3/PVDF energetic nanocomposites were easier to ignite and the burning was more durable, which was significant in solid propulsion and applications requiring extended combustion time.
Optimization of the recursive least squares algorithm for capacitive strain sensing
Authors: Bohnker Jillian , Breuer Kenneth
Published: November 2020

The use of dielectric elastomers as integrated actuators and strain sensors offers a simple approach for closed-loop control in a wide range of applications. While a number of approaches for self-sensing have been proposed, the adaptive online algorithm offers an appealing combination of high accuracy and low computational cost. In this work, the recursive least squares algorithm will be applied to capacitive deformation sensing of dielectric elastomers. With the goal of minimizing sampling rate while achieving a set accuracy over a desired range of deformation frequencies, the probe frequency, sampling frequency, and forgetting factor will be optimized. It will be shown that the accuracy is primarily determined by a nondimensionalized variable,

W

¯

, which defines the proportion of a hypothetical deformation cycle that is weighted more heavily by the algorithm. Ultimately, this optimized algorithm will be validated by variably inflating a dielectric elastomer membrane and comparing the algorithm output to membrane deformation measured by video.
Clinical profile and predictors of in-hospital mortality among older patients hospitalised for COVID-19
Authors: Becerra-Muñoz Víctor Manuel , Núñez-Gil Iván J , Eid Charbel Maroun , García Aguado Marcos , Romero Rodolfo , Huang Jia , Mulet Alba , Ugo Fabrizio , Rametta Francesco , Liebetrau Christoph , Aparisi Alvaro , Fernández-Rozas Inmaculada , Viana-Llamas María C , Feltes Gisela , Pepe Martino , Moreno-Rondón Luis A , Cerrato Enrico , Raposeiras-Roubín Sergio , Alfonso Emilio , Carrero-Fernández Ana , Buzón-Martín Luis , Abumayyaleh Mohammad , Gonzalez Adelina , Fernández Ortiz Antonio , Macaya Carlos , Estrada Vicente , Fernández-Pérez Cristina , Gómez-Doblas Juan José
Published: November 2020

Background

the coronavirus disease 2019 (COVID-19) is characterized by poor outcomes and mortality, particularly in older patients.

Methods

post hoc analysis of the international, multicentre, ‘real-world’ HOPE COVID-19 registry. All patients aged ≥65 years hospitalised for COVID-19 were selected. Epidemiological, clinical, analytical and outcome data were obtained. A comparative study between two age subgroups, 65–74 and ≥75 years, was performed. The primary endpoint was all cause in-hospital mortality.

Results

about, 1,520 patients aged ≥65 years (60.3% male, median age of 76 [IQR 71–83] years) were included. Comorbidities such as hypertension (69.2%), dyslipidaemia (48.6%), cardiovascular diseases (any chronic heart disease in 38.4% and cerebrovascular disease in 12.5%), and chronic lung disease (25.3%) were prevalent, and 49.6% were on ACEI/ARBs. Patients aged 75 years and older suffered more in-hospital complications (respiratory failure, heart failure, renal failure, sepsis) and a significantly higher mortality (18.4 vs. 48.2%, P < 0.001), but fewer admissions to intensive care units (11.2 vs. 4.8%). In the overall cohort, multivariable analysis demonstrated age ≥75 (OR 3.54), chronic kidney disease (OR 3.36), dementia (OR 8.06), peripheral oxygen saturation at admission <92% (OR 5.85), severe lymphopenia (<500/mm3) (OR 3.36) and qSOFA (Quick Sequential Organ Failure Assessment Score) >1 (OR 8.31) to be independent predictors of mortality.

Conclusion

patients aged ≥65 years hospitalised for COVID-19 had high rates of in-hospital complications and mortality, especially among patients 75 years or older. Age ≥75 years, dementia, peripheral oxygen saturation <92%, severe lymphopenia and qSOFA scale >1 were independent predictors of mortality in this population.
When life gives you lemons…
Authors: Bowler Sue
Published: November 2020

Sue Bowler finds some positive outcomes from 2020 for RAS 200 outreach projects.
How radio tuned in to dark matter
Authors: Byrd Gene , Valtonen Mauri
Published: November 2020

Gene Byrd and Mauri Valtonen describe how radio astronomy helped prove the existence of dark matter.
Optimizing digitalization effort in morphometrics
Authors: Evin Allowen , Bonhomme Vincent , Claude Julien
Published: November 2020

Quantifying phenotypes is a common practice for addressing questions regarding morphological variation. The time dedicated to data acquisition can vary greatly depending on methods and on the required quantity of information. Optimizing digitization effort can be done either by pooling datasets among users, by automatizing data collection, or by reducing the number of measurements. Pooling datasets among users is not without risk since potential errors arising from multiple operators in data acquisition prevent combining morphometric datasets. We present an analytical workflow to estimate within and among operator biases and to assess whether morphometric datasets can be pooled. We show that pooling and sharing data requires careful examination of the errors occurring during data acquisition, that the choice of morphometric approach influences amount of error, and that in some cases pooling data should be avoided. The demonstration is based on a worked example (Sus scrofa teeth) using a combinations of 18 morphometric approaches and datasets for which we identified and quantified several potential sources of errors in the workflow. We show that it is possible to estimate the analytical power of a study using a small subset of data to select the best morphometric protocol and to optimize the number of variables necessary for analysis. In particular, we focus on semi-landmarks, which often produce an inflation of variables in contrast to the number of available observations use in statistical testing. We show how the workflow can be used for optimizing digitization efforts and provide recommendations for best practices in error management.
Factors Associated with Attitudes and Knowledge of First-Semester College Students toward Climate Change
Authors: Harrod Sara E , Rolland Virginie
Published: November 2020

Despite scientific consensus and educational efforts, approximately 25% of Americans remain unconvinced of anthropogenic climate change (ACC), and significant misconceptions remain. Many studies have assessed adults’ views, but it is important to also understand the perceptions of younger individuals who will deal with the future impacts of ACC. In this study, we aimed to determine first-semester college students’ attitudes toward and knowledge of ACC, which factors are associated with these measures, and whether knowledge scores differ among audience segments. We issued surveys at 19 American universities and received 2355 responses. The surveys contained sections assessing attitudes, knowledge, and demographics. We analyzed the attitudes and knowledge in ordinal and beta regressions. Most (73.6%) of the students were very concerned about ACC, and their average knowledge scores were high (0.89, standard error = 0.003). Attitude and knowledge were associated with a combination of personal and environmental factors. The concerned students had higher scores, suggesting education may be an important mitigation tool.
The contradictory role of androgens in cutaneous and major burn wound healing
Authors: Shi Huaikai , Cheer Kenny , Simanainen Ulla , Lesmana Brian , Ma Duncan , Hew Jonathan J , Parungao Roxanne J , Li Zhe , Cooper Mark S , Handelsman David J , Maitz Peter K , Wang Yiwei
Published: November 2020

Wound healing is a complex process involving four overlapping phases: haemostasis, inflammation, cell recruitment and matrix remodeling. In mouse models, surgical, pharmacological and genetic approaches targeting androgen actions in skin have shown that androgens increase interleukin-6 and tumor necrosis factor-α production and reduce wound re-epithelization and matrix deposition, retarding cutaneous wound healing. Similarly, clinical studies have shown that cutaneous wound healing is slower in men compared to women. However, in major burn injury, which triggers not only local wound-healing processes but also systemic hypermetabolism, the role of androgens is poorly understood. Recent studies have claimed that a synthetic androgen, oxandrolone, increases protein synthesis, improves lean body mass and shortens length of hospital stay. However, the possible mechanisms by which oxandrolone regulates major burn injury have not been reported. In this review, we summarize the current findings on the roles of androgens in cutaneous and major burn wound healing, as well as androgens as a potential therapeutic treatment option for patients with major burn injuries.
A Connectomic Hypothesis for the Hominization of the Brain
Authors: Changeux Jean-Pierre , Goulas Alexandros , Hilgetag Claus C
Published: November 2020

Cognitive abilities of the human brain, including language, have expanded dramatically in the course of our recent evolution from nonhuman primates, despite only minor apparent changes at the gene level. The hypothesis we propose for this paradox relies upon fundamental features of human brain connectivity, which contribute to a characteristic anatomical, functional, and computational neural phenotype, offering a parsimonious framework for connectomic changes taking place upon the human-specific evolution of the genome. Many human connectomic features might be accounted for by substantially increased brain size within the global neural architecture of the primate brain, resulting in a larger number of neurons and areas and the sparsification, increased modularity, and laminar differentiation of cortical connections. The combination of these features with the developmental expansion of upper cortical layers, prolonged postnatal brain development, and multiplied nongenetic interactions with the physical, social, and cultural environment gives rise to categorically human-specific cognitive abilities including the recursivity of language. Thus, a small set of genetic regulatory events affecting quantitative gene expression may plausibly account for the origins of human brain connectivity and cognition.
Should Therapeutic Drug Monitoring Based on the Vancomycin Area Under the Concentration-Time Curve Be Standard for Serious Methicillin-Resistant Staphylococcus aureus Infections?—No
Authors: Jorgensen Sarah C J , Spellberg Brad , Shorr Andrew F , Wright William F
Published: November 2020

In this counterpoint we critically appraise the evidence supporting therapeutic drug monitoring based on the vancomycin 24-hour area under the concentration-time curve (AUC24) for serious methicillin-resistant Staphylococcus aureus infections. We reveal methodologically weaknesses and inconsistencies in the data and suggest that, in the absence of clear and convincing evidence of benefit compared with modestly reducing trough targets, alternative strategies are more likely to result in superior safety and efficacy. These include focusing on fundamental antibiotic stewardship to limit vancomycin exposure overall, achieving earlier and more complete source control, and establishing alternative therapeutic options to vancomycin. Implementation of AUC24-based therapeutic drug monitoring will take resources away from these more promising, alternative solutions.
Bayesian inference of network structure from unreliable data
Authors: Young Jean-Gabriel , Cantwell George T , Newman M E J
Published: November 2020

Most empirical studies of complex networks do not return direct, error-free measurements of network structure. Instead, they typically rely on indirect measurements that are often error prone and unreliable. A fundamental problem in empirical network science is how to make the best possible estimates of network structure given such unreliable data. In this article, we describe a fully Bayesian method for reconstructing networks from observational data in any format, even when the data contain substantial measurement error and when the nature and magnitude of that error is unknown. The method is introduced through pedagogical case studies using real-world example networks, and specifically tailored to allow straightforward, computationally efficient implementation with a minimum of technical input. Computer code implementing the method is publicly available.
Post-operative pain following cardiac implantable electronic device implantation: insights from the BRUISE CONTROL trials
Authors: Nair Girish M , Birnie David H , Sumner Glen L , Krahn Andrew D , Healey Jeffrey S , Nery Pablo B , Kalfon Eli , Verma Atul , Ayala-Paredes Felix , Coutu Benoit , Becker Giuliano , Philippon François , Eikelboom John , Sandhu Roopinder K , Sapp John , Leather Richard , Yung Derek , Thibault , Bernard , Simpson Christopher S , Ahmad Kamran , Sturmer Marcio , Kavanagh Katherine , Crystal Eugene , Wells George A , Essebag Vidal ,   for the BRUISE CONTROL Investigators
Published: November 2020

Aims 

Post-operative pain following cardiac implantable electronic device (CIED) insertion is associated with patient dissatisfaction, emotional distress, and emergency department visits. We sought to identify factors associated with post-operative pain and develop a prediction score for post-operative pain.

Methods and results 

All patients from the BRUISE CONTROL-1 and 2 trials were included in this analysis. A validated Visual Analogue Scale (VAS) was used to assess the severity of pain related to CIED implant procedures. Patients were asked to grade the most severe post-operative pain, average post-operative pain, and pain on the day of the first post-operative clinic. Multivariable regression analyses were performed to identify predictors of significant post-operative pain and to develop a pain-prediction score. A total of 1308 patients were included. Multivariable regression analysis found that the presence of post-operative clinically significant haematoma {CSH; P value < 0.001; odds ratio (OR) 3.82 [95% confidence interval (CI): 2.37–6.16]}, de novo CIED implantation [P value < 0.001; OR 1.90 (95% CI: 1.47–2.46)], female sex [P value < 0.001; OR 1.61 (95% CI: 1.22–2.12)], younger age [<65 years; P value < 0.001; OR 1.54 (95% CI: 1.14–2.10)], and lower body mass index [<20 kg/m2; P value < 0.05; OR 2.05 (95% CI: 0.98–4.28)] demonstrated strong and independent associations with increased post-operative pain. An 11-point post-operative pain prediction score was developed using the data.

Conclusion 

Our study has identified multiple predictors of post-operative pain after CIED insertion. We have developed a prediction score for post-operative pain that can be used to identify individuals at risk of experiencing significant post-operative pain.
Proteomic characterization of a second-generation version of the BCGΔBCG1419c vaccine candidate by means of electrospray-ionization quadrupole time-of-flight mass spectrometry
Authors: Velázquez-Fernández Jesús Bernardino , Ferreira-Souza Gustavo Henrique Martins , Rodríguez-Campos Jacobo , Aceves-Sánchez Michel de Jesús , Bravo-Madrigal Jorge , Vallejo-Cardona Alba Adriana , Flores-Valdez Mario Alberto
Published: November 2020

Tuberculosis (TB) is the most important infectious disease worldwide, based on the number of new cases and deaths reported by the World Health Organization. Several vaccine candidates against TB have been characterized at preclinical and clinical levels. The BCGΔBCG1419c vaccine candidate, which lacks the BCG1419c gene that encodes for a c-di-GMP phosphodiesterase, provides improved efficacy against chronic TB, reactivation from latent-like infection and against chronic TB in the presence of type 2 diabetes in murine models. We previously reported that compared with wild type BCG, BCGΔBCG1419c changed levels of several proteins. Here, using a label-free proteomic approach, we confirmed that a novel, second-generation version of BCGΔBCG1419c maintains changes in antigenic proteins already reported, and here we further found differences in secreted proteins, as well as that this new BCGΔBCG1419c version modifies its production of proteins involved in redox and nitrogen/protein metabolism compared with wild type BCG. This work contributes to the proteomic characterization of a novel vaccine candidate that is more effective against TB than parental BCG in diverse murine models.
A proteomic glimpse into the effect of antimalarial drugs onPlasmodium falciparumproteome towards highlighting possible therapeutic targets
Authors: Dousti Majid , Manzano-Román Raúl , Rashidi Sajad , Barzegar Gholamreza , Ahmadpour Niloofar Bavarsad , Mohammadi Alireza , Hatam Gholamreza
Published: November 2020

There is no effective vaccine against malaria; therefore, chemotherapy is to date the only choice to fight against this infectious disease. However, there is growing evidences of drug-resistance mechanisms in malaria treatments. Therefore, the identification of new drug targets is an urgent need for the clinical management of the disease. Proteomic approaches offer the chance of determining the effects of antimalarial drugs on the proteome of Plasmodium parasites. Accordingly, we reviewed the effects of antimalarial drugs on the Plasmodium falciparum proteome pointing out the relevance of several proteins as possible drug targets in malaria treatment. In addition, some of the P. falciparum stage-specific altered proteins and parasite–host interactions might play important roles in pathogenicity, survival, invasion and metabolic pathways and thus serve as potential sources of drug targets. In this review, we have identified several proteins, including thioredoxin reductase, helicases, peptidyl-prolyl cis–trans isomerase, endoplasmic reticulum-resident calcium-binding protein, choline/ethanolamine phosphotransferase, purine nucleoside phosphorylase, apical membrane antigen 1, glutamate dehydrogenase, hypoxanthine guanine phosphoribosyl transferase, heat shock protein 70x, knob-associated histidine-rich protein and erythrocyte membrane protein 1, as promising antimalarial drugs targets. Overall, proteomic approaches are able to partially facilitate finding possible drug targets. However, the integration of other ‘omics’ and specific pharmaceutical techniques with proteomics may increase the therapeutic properties of the critical proteins identified in the P. falciparum proteome.
Comparative Genomics within and across Bilaterians Illuminates the Evolutionary History of ALK and LTK Proto-Oncogene Origination and Diversification
Authors: Dornburg Alex , Wang Zheng , Wang Junrui , Mo Elizabeth S , López-Giráldez Francesc , Townsend Jeffrey P
Published: November 2020

Comparative genomic analyses have enormous potential for identifying key genes central to human health phenotypes, including those that promote cancers. In particular, the successful development of novel therapeutics using model species requires phylogenetic analyses to determine molecular homology. Accordingly, we investigate the evolutionary histories of anaplastic lymphoma kinase (ALK)—which can underlie tumorigenesis in neuroblastoma, nonsmall cell lung cancer, and anaplastic large-cell lymphoma—its close relative leukocyte tyrosine kinase (LTK) and their candidate ligands. Homology of ligands identified in model organisms to those functioning in humans remains unclear. Therefore, we searched for homologs of the human genes across metazoan genomes, finding that the candidate ligands Jeb and Hen-1 were restricted to nonvertebrate species. In contrast, the ligand augmentor (AUG) was only identified in vertebrates. We found two ALK-like and four AUG-like protein-coding genes in lamprey. Of these six genes, only one ALK-like and two AUG-like genes exhibited early embryonic expression that parallels model mammal systems. Two copies of AUG are present in nearly all jawed vertebrates. Our phylogenetic analysis strongly supports the presence of previously unrecognized functional convergences of ALK and LTK between actinopterygians and sarcopterygians—despite contemporaneous, highly conserved synteny of ALK and LTK. These findings provide critical guidance regarding the propriety of fish and mammal models with regard to model organism-based investigation of these medically important genes. In sum, our results provide the phylogenetic context necessary for effective investigations of the functional roles and biology of these critically important receptors.
Taking a Break: Daily Respite Effects of Adult Day Services as Objective and Subjective Time Away From Caregiving
Authors: Wylie Molly J , Kim Kyungmin , Liu Yin , Zarit Steven H
Published: November 2020

Background and Objectives

Adult day services (ADS) can provide emotional and physical relief for caregivers of persons with dementia. While prior studies conceptualized ADS use at the aggregate level as a dichotomous construct, little is known about objective and subjective respite as distinct constructs. This study investigated how objective and subjective breaks from caregiving were associated with caregivers’ daily emotional well-being.

Research Design and Methods

Family caregivers (N = 173) whose relatives were using ADS at least twice a week participated in daily interviews over 8 consecutive days (day N = 1,359). Participants provided information on daily respite hours and daily affect. They also reported perceived frequency of breaks from caregiving responsibilities and primary and secondary caregiving stressors (i.e., overload and work conflict). Multilevel models were used to examine the research questions.

Results

On average, caregivers reported 7.12 respite hours on ADS days and 1.74 respite hours on non-ADS days. Having more objective respite was associated with higher positive affect, whereas more subjective respite was associated with lower negative affect, after controlling for ADS use and other covariates. Further, caregivers with greater work conflict experienced more benefits to their positive affect as a result of objective respite.

Discussion and Implications

Objective and subjective respite are unique aspects of caregiving that may have varying impact on caregivers. Respite may be especially beneficial for caregivers experiencing conflict between work and caregiving.
A proteomic approach reveals possible molecular mechanisms and roles for endosymbiotic bacteria in begomovirus transmission by whiteflies
Authors: Kliot Adi , Johnson Richard S , MacCoss Michael J , Kontsedalov Svetlana , Lebedev Galina , Czosnek Henryk , Heck Michelle , Ghanim Murad
Published: November 2020

Background

Many plant viruses are vector-borne and depend on arthropods for transmission between host plants. Begomoviruses, the largest, most damaging and emerging group of plant viruses, infect hundreds of plant species, and new virus species of the group are discovered each year. Begomoviruses are transmitted by members of the whitefly Bemisia tabaci species complex in a persistent-circulative manner. Tomato yellow leaf curl virus (TYLCV) is one of the most devastating begomoviruses worldwide and causes major losses in tomato crops, as well as in many agriculturally important plant species. Different B. tabaci populations vary in their virus transmission abilities; however, the causes for these variations are attributed among others to genetic differences among vector populations, as well as to differences in the bacterial symbionts housed within B. tabaci.

Results

Here, we performed discovery proteomic analyses in 9 whitefly populations from both Middle East Asia Minor I (MEAM1, formerly known as B biotype) and Mediterranean (MED, formerly known as Q biotype) species. We analysed our proteomic results on the basis of the different TYLCV transmission abilities of the various populations included in the study. The results provide the first comprehensive list of candidate insect and bacterial symbiont (mainly Rickettsia) proteins associated with virus transmission.

Conclusions

Our data demonstrate that the proteomic signatures of better vector populations differ considerably when compared with less efficient vector populations in the 2 whitefly species tested in this study. While MEAM1 efficient vector populations have a more lenient immune system, the Q efficient vector populations have higher abundance of proteins possibly implicated in virus passage through cells. Both species show a strong link of the facultative symbiont Rickettsia to virus transmission.
Perigraft reaction and incorporation of porcine and bovine pericardial patches
Authors: Schlachtenberger Georg , Doerr Fabian , Brezina Annamaria , Menghesha Hruy , Heldwein Matthias B , Bennink Gerardus , Menger Michael D , Moussavian Mohammed , Hekmat Khosro , Wahlers Thorsten
Published: November 2020

OBJECTIVES

Bovine and porcine pericardial patches are frequently used in cardiothoracic and vascular surgery. There are no guidelines recommending the usage of these patches for particular surgical approaches. However, these 2 materials supposedly possess different properties. The clinical advantage of porcine compared with bovine patches remains controversial. In this experimental study, we analysed the incorporation and vascularization of bovine and porcine pericardial patches during the initial phase after implantation.

METHODS

Bovine and porcine pericardial patches were implanted into the dorsal skinfold chamber of C57BL/6 mice (n = 8 per group) to study vascularization and inflammation at the implantation site using repetitive intravital fluorescence microscopy over a 14-day period. At the end of the in vivo experiments, CD-31-positive cells were determined to evaluate the vascularization by immunohistochemistry. Furthermore, cell proliferation and apoptosis were analysed immunohistochemically.

RESULTS

Implanted bovine patches exhibited an enhanced vascularization, as indicated by a significantly higher number of CD-31-positive cells and micro-vessels (23.2 ± 4.3 vs 16.5 ± 5.8 mm−2; P = 0.001). Furthermore, bovine patches showed a slightly but not significantly higher functional capillary density. Both patches induced a moderate leukocytic inflammatory host tissue response, and neither bovine nor porcine patches significantly affected apoptosis and cell proliferation at the implantation site.

CONCLUSIONS

Bovine and porcine pericardial patches are similarly suitable for surgery. Bovine patches exhibited an improved vascularization during the first 14 days after implantation. This may result in a quicker and improved incorporation into the surrounding tissue compared with porcine pericardial patches.
‘Ending the Silence’: Addressing the Legacy of Displacement in Northern Ireland’s ‘Troubles’
Authors: Gilmartin Niall
Published: November 2020

Though transitional justice measures are increasingly used to address displacement, particularly restitution programmes and truth-telling initiatives, the issue of addressing the long-term impact of displacement on individuals, communities and wider society represents significant challenges for peacebuilding processes. Based on in-depth interviews with those who suffered displacement in Northern Ireland’s ‘Troubles’, this article seeks to explore the marginalized and often silenced narratives of those displaced, shedding light on the multi-layered short- and long-term harms and consequences of displacement for individuals, families and community relations. The article’s argument is twofold: first, that experiences of displacement should be considered as a form of conflict-related harm and trauma and those displaced recognized as victims. And second, that ‘storytelling’ and other bottom-up acknowledgement projects are seen by victims and survivors as an effective vehicle to ‘break’ the silence, end the denial and advance their pursuit of recognition and acknowledgement.
Making Peace or Preventing It? UN Peacekeeping, Terrorism, and Civil War Negotiations
Authors: Hinkkainen Elliott Kaisa , Polo Sara M T , Reyes Liana Eustacia
Published: November 2020

Previous studies have highlighted that United Nations (UN) peacekeeping operations are effective at reducing violence during civil wars. But can these operations also change the incentives of the warring parties and lead them to pursue non-violent alternatives? This article provides the first direct test of UN peacekeeping troops’ effectiveness at inducing non-violent engagements, specifically negotiations during civil wars. Our analysis of disaggregated monthly data on peace operations, negotiations, and violence in African conflicts (1989–2009) reveals that sizable deployments of UN military troops, by themselves, are insufficient to foster negotiations, even when they reduce battlefield violence. Instead, the probability of negotiation instances is conditional on rebel tactics. We posit, when rebels engage in terrorism, peacekeeping troops can inadvertently alter the “power to hurt” of the belligerents in favor of rebel groups and create conditions conducive to negotiations. Our results have important implications for research on the effectiveness of both peacekeeping and terrorism and for policy-making.
Big data and competition analysis under Australian competition law: comeback of the structuralist approach?
Authors: Balasingham Baskaran , Jordan Hannah
Published: November 2020

Competition assessment in Australia has traditionally been based on an evaluation of the market structure relying on five factors, namely the degree of market concentration, the height of barriers to entry, the extent of product differentiation, the extent of vertical integration, and the nature of arrangements between firms. These factors, known as the ‘QCMA factors’, are characteristic of competition in the manufacturing industries of the ‘old economy’. Since the ascendancy of Chicago and Post-Chicago School thinking competition analysis in Australia has also taken into consideration non-structural factors. However, in light of the dominance of big tech companies in online markets, the so-called ‘Neo-Brandeisian School’ has advocated focusing on structural elements that are characteristic of online markets. This article examines to what extent the QCMA factors still a suitable structural framework for the assessment of competition in online markets.
The Getty Gnaios
Authors: Lapatin Kenneth
Published: November 2020

An amethyst intaglio depicting the Roman general Mark Antony and inscribed ‘Gnaios’ has been much lauded and frequently illustrated over the past fifty years. Other gems signed by this ancient engraver have been prized, replicated and forged for centuries. This article traces the amethyst, previously in the Ionides collection and acquired by the J. Paul Getty Museum in 2001, to the possession of Prince Stanislas Poniatowski, and demonstrates that, rather than dating to the late first century bc, it was cut by Giovanni Calandrelli between 1817 and 1824, apparently to complement a similarly inscribed gem thought to depict Cleopatra. The amethyst’s reception exemplifies the desire of collectors to possess creations of renowned artists, scholars eager to construct compelling narratives around superb works of art, and over-optimistic reliance on expert authority. ‘Master Gnaios’ even appears in well-researched historical fiction. Thus, the Getty gem is another demonstration of the enduring and transformative power of outstanding forgeries.