bluuebunny/crossref_metadata_2025 huggingface dataset:
Control of bacterial leaf blight and rice blast with antagonist microbial in the agroecosystem of irrigated rice
Authors: Pustika A B , Yolanda K , Sudarmaji
Published: February 2021

Bacterial leaf blight (Xanthomonas oryzae) and rice blast (Pyricularia oryzae) cause yield losses in rice production. Antagonist microbial application through seed treatment and foliar spray during rice growing stage is suggested to prevent the disease which is more reliable to reduce the disease incidence than curing it. This research aimed to determine the severity of bacterial leaf blight and rice blast among varieties that treated with antagonist microbial complex in the agro ecosystem of irrigated rice. Research was conducted in Kalibawang sub district, Kulon Progo, Yogyakarta, October 2018 to January 2019. The experimental design was randomized block design with 7 treatments and 4 replications. The treatments were the application of antagonist microbial complex formula A (Azotobacter
vinelandii, Azospirillum sp., Bacillus cereus, Bradyzhizobium sp., and Methylobacterium sp. >107 CFU/g) and formula B (Azotobacter
chroococum, Azotobacter
vinelandii, Azospirillum sp., Pseudomonas
cepacia, Penicillium sp., and Acinetobacter sp. >107 CFU/g) to several rice varieties (Inpari 9, Inpari 33, and Ciherang). Results shows that formula B had the lowest severity of bacterial leaf blight (14.44%) and leaf blast (6.94%) at Ciherang while formula A had the lowest panicle blast (6.55%). The highest yield (10.62 t/ha) was obtained from Ciherang treated with formula B.
The elastic, strength and thermophysical characteristics modeling of mono- and polycrystalline aluminum Al
Authors: Kh Badamshin I
Published: February 2021

Temperature dependences of mechanical and thermophysical properties of the material are the initial data for estimating the stress-strain state of structural elements. However, when designing, the amount of this data is usually not enough. Under these conditions, the problem of modeling these properties arises. This problem is solved by taking into account the forces of interatomic interaction in the crystal structure on the example of a single crystal and polycrystal of aluminum. The results of calculating the elastic modulus, elastic limit and yield strength, Poisson’s ratio, coefficients of thermal conductivity, thermal expansion and material density are presented. A satisfactory convergence with the available reference data is obtained. The results obtained can be used as input data for the construction of compositions and alloys based on aluminum.
The validation system for reliability and survivability of unique mechanical systems
Authors: Berman A F , Nikolaichuk O A , Yu Yurin A
Published: February 2021

We propose a concept of the validation system for the properties of reliability and survivability of unique mechanical systems, the failures of which can result in accidents. The system is based on the principles of self-organization and provides the opportunity to consider off-design impacts of any origin, errors in design and operation based on the use of appropriate rules formulated by experts. The principles of self-organization are implemented by a mechanism based on the rules that step-by-step formulate the necessary tasks, the required expert systems and computing units to solve them, as well as on the rules directly linking negative factors and neutralizing their properties.
Mathematical diagnostic model of brake master cylinder of hydraulic brake system of automobile
Authors: Borodin A L , Vasiliev V I , Maltseva G I
Published: February 2021

The article considers a dynamic mathematical model of a new method of componentwise diagnosis of the brake master cylinder of a “tandem” type of the hydraulic brake system. We propose a variant of how simulated various faults affect the output parameters of brake process on the basis of mathematical modeling.
Mathematical analysis of the model of a low-melting metal coating on the surface of the guide
Authors: Mukutadze M A , Lagunova E O , Zadorozhnaya N S
Published: February 2021

The work presents the asymptotic solution of the system of differential equations in the form of series in powers of the parameter due to the melt of the surface of the guide covered with a low-melting metal alloy and the rate of dissipation of mechanical energy, taking into account the dependence of the viscosity of the lubricant on pressure. Subsequently, a self-similar solution was found, as a result of which the fields of velocities, pressure and the main operating characteristics, load capacity and friction force were determined when the working gap was not completely filled with lubricant.
Mathematical model of a micropolar lubricating stuff
Authors: Mukutadze M A , Mukutadze A M , Opatskikh A N , Novakovich M V , Poltinnikov V I
Published: February 2021

The article is devoted to the mathematical analysis model of the radial bearing of infinite length, lubricated with lubricating stuff and molten low-melting metal coating on the surface of the bearing bush, having the general rheological properties in the laminar condition of micro-polar lubrication properties, taking into account the dependence of viscosity rheological properties of micro-polar lubricating stuff, and the permeability of the porous coating from the pressure. The authors on the basis of the motion equations of a viscous incompressible fluid having micro-polar properties, and for “lamina”, of the continuity equation, Darcy equation and determining from the expression for the dissipation rate of mechanical energy, the profile of molten contour of the bearing bush, while taking account of the dependence of the overall rheological properties of the lubricating stuff and melt the low-melting metal coating having the micro-polar properties and the permeability of the porous coating of the pressure found the asymptotic and exact self-similar solution of the differential equation system on the parameter, due to the melt and the dissipation rate of mechanical energy to zero (without melt) and first (including melt) approximation.
Mathematical modeling of the percussion mechanism with a single impact energy increase
Authors: Zedgenizov V G , Kokourov D V , Senotrusova T A
Published: February 2021

The present study aims to develop a mathematical model of the percussion mechanism with a single impact energy increase and determine the influence of the spring stiffness and the ratio of inertial and projectile masses on the main parameters of the destruction process. The method of mathematical modeling of the destruction process was applied. A mathematical model of the percussion mechanism with a single impact energy increase and a diagram for its solution in Matlab-Simulink have been developed; dependences of the main parameters of the desctrution process on the spring stiffness and the ratio of inertial and projectile masses have been obtained. The mathematical model of the percussion mechanism makes it possible to increase the energy of a single impact by three-five times in comparison with a freely falling projectile. The reactive component is not transmitted to the base machine.
The main technical solutions for the creation of an automated control system for the technological process of thermal vortex enrichment
Authors: Gorovoy V O , Govorkov A S , Kondrat’ev V V , Kononenko R V , Pestova A M
Published: February 2021

The main technical solutions for the creation of an automated control system for the technological process of thermal vortex enrichment were adopted for the creation of an integrated resource-saving technology and the organization of high-tech production of nanostructures based on carbon and silicon dioxide to improve the properties of building and structural materials using control digitalization techniques technological processes. The decisions were made taking into account the dependence of the process of obtaining a modifying additive containing nanostructures in the form of spherical silicon dioxide on a large number of interrelated variables, a variety of operating modes of the technological line, and instantaneous changes in parameters. Technical solutions have been developed for the structure, means and methods of communication for information exchange; interconnection with adjacent systems, ensuring its compatibility; modes of operation, diagnostics of system operation; number, qualifications and functions of personnel, modes of their work, the order of interaction. This includes also requirements for ensuring the given consumer characteristics of the system, which determine its quality; the composition of functions, complexes of tasks implemented by the system; a set of technical means, its placement at the facility. Besides, it concerns the composition of information, volume, methods of its organization, types of machine media, input and output documents and messages, information processing sequence and other components; the composition of software, languages of activity.
Modernization of technological equipment in the waste water purification process behind the coke oven using the organic Rankine cycle
Authors: Shishkov A N , Osintsev K V
Published: February 2021

The authors analyzed the state of the process scheme, which is a structural part of the water supply treatment facilities. The research results can be applied in oil and gas, chemical, metallurgical and energy industries. In particular, the authors for the first time propose an efficient scheme for the reuse of heat to obtain purified water. Currently, a way to reduce energy consumption by introducing a plant based on an organic Rankine cycle has been considered. The metallurgical production has such equipment as converters, coke ovens, scrubbers, gas ducts, cooling boilers, waste heat boilers. The heat recovery schemes developed by the authors increase the efficiency of the process equipment in the metallurgical industry. In the work of enterprises, low-potential heat of soil, water, air is increasingly used. One of the main directions of energy saving to increase the energy efficiency of the boiler house is to increase the heat utilization rate of the fuel at power plants. Boiler houses that run on gas lose at least 13-18% of heat with flue gases. In the article, the authors propose to combine the methods of heat utilization. Namely, a contact heat exchanger and an organic Rankine cycle are used. The water temperature is significantly reduced due to the fact that the collectors are designed to transport water. In this regard, experts consider it expedient to utilize the heat of wastewater not only at treatment plants, but also directly in the building itself. Prospects for the use of the authors’ developments are associated with their further implementation at industrial enterprises of the metallurgical industry.
Geotechnical monitoring of frozen soils: problems and possible solutions
Authors: Potapov A I , Shikhov A I , Dunaeva E N
Published: February 2021

A great part of the territory of the Russian Federation is located in the zone of permafrost soils. Safe operation management of buildings and structures, in permafrost conditions, requires geotechnical monitoring of subgrade soils. The increase in air temperature recorded during numerous monitoring leads to the degradation of permafrost soils. Therefore, the problem of conducting geotechnical monitoring becomes more urgent than ever. This paper analyzes the existing methods and systems for geotechnical monitoring of permafrost soils. The authors reveal the drawbacks of the applied methods and the reasons that do not allow assessing the state of frozen soils with sufficient accuracy. In order to solve these problems, it is proposed to use an active acoustic method of non-destructive testing and create a system that combines an engineering-geological method determining the deformation properties of frozen soils and active acoustic method.
Geological and technological substantiation of waterflooding systems in deposits with hard-to-recover reserves
Authors: Mukhametshin V Sh , Tyncherov K T , Rakhimov N
Published: February 2021

The study of the process of developing oil reserves in one of the fields with hard-to-recover reserves of the Tournaisian stage of the Volga-Ural oil and gas basin. A significant increase in the oil recovery factor was established when using in-circuit waterflooding as compared to the development of deposits in natural mode. The influence on the degree of reserves recovery is shown by the density of the grid of wells, geological heterogeneity, the sweep efficiency by injection by thickness, variations in the injectivity profile in injection wells. Models are proposed to assess the parameters of the efficiency of waterflooding systems.
Influence of target temperature on AlO emission of femtosecond laser-induced Al plasmas
Authors: QI Wei , WANG Qiuyun , SHAO Junfeng , CHEN Anmin , JIN Mingxing
Published: February 2021

The influence of the target temperature on the molecular emission of femtosecond laser-induced breakdown spectroscopy (LIBS) was investigated experimentally. An Al target was ablated to produce laser-induced plasma. The Al target was uniformly heated to a maximum of 250 °C. The measured molecular emission was AlO (Δν = 0) from the femtosecond LIBS of the Al target. The measurements indicated that the molecular emission of AlO increased as the temperature of the Al target increased. In addition, a two-temperature model was used to simulate the evolution of the electron and lattice temperature of the Al target with different initial temperatures. The simulated results showed that the electron and lattice temperatures of Al irradiated by the femtosecond laser increased as the initial temperature of the Al target increased; also, the simulated ablated depth increased. Therefore, an increase in the initial Al target temperature resulted in an enhancement in the spectral signal of AlO from the femtosecond LIBS of Al, which was directly related to the increase in the size of the ablated crater. The study suggested that increasing the temperature of the target improves the intensity of molecular emission in femtosecond LIBS.
Fully printed, stretchable and wearable bioimpedance sensor on textiles for tomography
Authors: Jose Manoj , Lemmens Marijn , Bormans Seppe , Thoelen Ronald , Deferme Wim
Published: February 2021

Electrical impedance tomography (EIT) is a non-invasive, real-time, continuous imaging technique that has multiple applications in health care. EIT is a realizable technique for radiation-free medical imaging ranging from real-time monitoring of bone fracture repair to lung functioning. This work explores the prospect of printing a wearable bioimpedance sensor on textiles for EIT imaging. Screen printing and stencil printing were applied to fabricate the sensor on the textile substrate and the imaging was carried out with the worn sensor on the human body. The first part of this work focuses on developing a flexible textile sensor in the form of a bracelet to obtain cross-sectional images of the forearm that unravel bone features like shape, size and position. However, body parts such as the thorax have added complexities due to their constantly varying perimeter and uneven shape. It is a significant prerequisite for the wearable sensors to apply to dynamic body parts where irregular shape and continuous volume variations occur. The second part of the paper therefore addresses the fabrication and testing of a stretchable textile-based sensor to address such instances of body dynamicity. The proposed stretchable sensor, worn on the thorax, demonstrates the feasibility of imaging such an uneven and dynamic body part. Although the EIT images are inherently attributed to low resolution, this work shows the prospect of wearable imaging applications in health monitoring. Apart from demonstrating the printed sensor for EIT imaging, this paper shows the image rendering quality dependency over the frequency of the signal and the number of electrodes. This work could initiate further research on wearable EIT based health monitoring devices for real-life scenarios.
In-plane vibration detection using sampling moiré method
Authors: Yadi Mona , Morimoto Yoshiharu , Ueki Masaki , Takaya Yasuhiro
Published: February 2021

Various methods have been proposed to measure vibration frequency. However, mechanical systems are not efficient as they have to be attached to the object of interest. So, the measurements are not precise when a new mass is introduced to the vibration surface. Besides, obtaining the power and phase distribution on the whole surface of the vibrating object is not possible through using accelerometers or other mechanical vibrometers. Out-of-plane vibration detection was previously proposed by one of the authors, using one pitch phase analysis method. In this paper, a novel accurate in-plane vibration detection technique by using sampling moiré method is proposed. This paper is the first published report on the in-plane vibration distribution of an industrial scale size object. Since noncontact deformation distribution of a deformed body is possible using sampling moiré method, in this study sampling moiré method is applied to vibration analysis of a tuning fork using a high-speed camera. This paper shortly describes the principle of in-plane vibration detection method and compares the experimental in-plane frequency results with those obtained by an accurate laser displacement meter. Moreover, for the first time, power and phase distribution graphs of the whole surface of the tuning fork, in two different frequency modes, are obtained. This technology will be useful for vibration investigation in any movable object on an industrial scale.
Theoretical investigation of quantum capacitance in the functionalized MoS2-monolayer
Authors: T Sruthi , Devaraj Nayana , Tarafder Kartick
Published: February 2021

In this work, we investigated the electronic structure and the quantum capacitance of a set of functionalized MoS2 monolayers. The functionalizations have been done by using different ad-atom adsorption on MoS
2 monolayer. Density functional theory calculations are performed to obtain an accurate electronic structure of ad-atom doped MoS2 monolayer with a varying degree of doping concentration. Subsequently, the quantum capacitance in each functionalized system was estimated. A marked quantum capacitance above 200 μF cm−2 has been observed. Our calculations show that the quantum capacitance of MoS2 monolayer is significantly enhanced with substitutional doping of Mo with transition metal ad-atoms. The microscopic origin of such enhancement in quantum capacitance in this system has been analyzed. Our DFT-based calculation reveals that the generation of new electronic states at the proximity of the band-edge and the shift of Fermi level caused by the ad-atom adsorption results in a very high quantum capacitance in the system.
Explorations on the electronic structure and spectroscopic IR assignments of 5-methyl-2-(2-oxopropyl)-pyrazolo[5,1-b]quinazolin-9(3H)-one molecule
Authors: Kumar Dilip , Kushwaha Vijay , Yadava Umesh
Published: February 2021

In the present work, theoretical investigations on a quinazoline derivate, 5-methyl-2-(2-oxopropyl)pyrazolo[5,1-b]quinazolin-9(3H)-one, have been carried out through quantum mechanical density functional B3LYP/6-31G(d,p) method to explore its electronic structure and vibrational features. The normal modes analysis was executed to predict the contributions of different vibrational modes at the required frequencies in the infrared region and the spectral peaks have been assigned accordingly. Besides, certain electronic properties that are associated with chemical reactivity like, HOMO-LUMO energy gap, molecular electrostatic potential, Mulliken partial charges, etc have been estimated and discussed herein. It has been established that the molecule is chemically reactive and may be used in designing drugs as COX-2/5-LOX inhibitor.
Spatial regulation of MCAK promotes cell polarization and focal adhesion turnover to drive robust cell migration
Authors: Zong Hailing , Hazelbaker Mark , Moe Christina , Ems-McClung Stephanie C. , Hu Ke , Walczak Claire E.
Published: February 2021

MCAK activity is spatially regulated in migrating cells in which its activity is lower at the leading edge than the trailing edge. Global inhibition of MCAK disrupts this spatial regulation and causes defects in centrosome re-orientation and focal adhesion turnover that reduces cell polarization needed for robust directed migration.
Impact of the Apolipoprotein E ε4 Allele on the Relationship Between Healthy Lifestyle and Cognitive Decline: A Population-Based Study
Authors: Dhana Klodian , Aggarwal Neelum T , Rajan Kumar B , Barnes Lisa L , Evans Denis A , Morris Martha C
Published: February 2021

Adherence to a healthy lifestyle—characterized by abstaining from smoking, being physically and cognitively active, having a high-quality diet, and limiting alcohol use—is associated with slower cognitive decline in older adults, but whether this relationship extends to persons with a genetic predisposition (e.g., carriers of the ε4 allele of the apolipoprotein E gene (APOE*E4)) remains uncertain. Using data from a population-based study, the Chicago Health and Aging Project (Chicago, Illinois), we followed 3,886 individuals who underwent regular clinical and cognitive assessments from 1993 to 2012. Of 3,886 older adults, 1,269 (32.7%) were APOE*E4 carriers. Compared with noncarriers, APOE*E4 carriers had faster cognitive decline (β = −0.027 units/year, 95% confidence interval (CI): –0.032, −0.023). In contrast, persons with 2–3 and 4–5 healthy lifestyle factors had slower cognitive decline (β = 0.008 units/year (95% CI: 0.002, 0.014) and β = 0.019 units/year (95% CI: 0.011, 0.026), respectively) compared with those with 0–1 factor. In analyses stratified by APOE*E4 status, adherence to a healthy lifestyle (e.g., 4–5 factors vs. 0–1 factors) was associated with a slower rate of cognitive decline in both APOE*E4 carriers (β = 0.029, 95% CI: 0.013, 0.045) and noncarriers (β = 0.013, 95% CI: 0.005, 0.022). These results underscore the impact of a healthy lifestyle on cognition, particularly among persons with a genetic predisposition, who are more vulnerable to cognitive decline as they age.
Impartiality and independence: fundamental and fluid
Authors: van Haersolte-van Hof Jacomijn J
Published: February 2021

In this article, the author discusses the paradox between the fundamentality of arbitrator impartiality and independence and the fluidity of the applicable norms. These norms differ over time and place, and vary depending on the type of arbitration, the stage of the proceedings and the applicable rules and laws. While standards applicable to judges have some relevance for this discussion, they cannot be equated with the standards for arbitrators. The recent English Supreme Court decision in Halliburton v Chubb is used to illustrate various aspects of the discussion.
Particulate Debris Released From Breast Implant Surfaces Is Highly Dependent on Implant Type
Authors: Hallab Nadim James , Samelko Lauryn , Hammond Dennis
Published: February 2021

Background

Although breast implants (BIs) have never been safer, factors such as implant debris may influence complications such as chronic inflammation and illness such as ALCL (anaplastic large cell lymphoma). Do different types of BIs produce differential particulate debris?

Objectives

The aim of this study was to quantify, investigate, and characterize the size, amount, and material type of both loosely bound and adherent surface particles on 5 different surface types of commercial BIs.

Methods

Surface particles from BIs of 5 surface types (n = 5/group), Biocell, Microcell, Siltex, Smooth, SmoothSilk, and Traditional-Smooth, were: (1) removed by a rinsing procedure and (2) removed with ultrapure adhesive carbon tabs. Particles were characterized (ASTM 1877-16) by scanning electron microscopy and energy-dispersive X-ray chemical analysis.

Results

Particles rinsed from Biocell, Microcell and Siltex were <1 μm in diameter whereas SmoothSilk and Traditional-Smooth surfaces had median sizes >1 μm (range, 0.4-2.7 μm). The total mass of particles rinsed from the surfaces indicated Biocell had >5-fold more particulate compared with all other implants, and >30-fold more than SmoothSilk or Traditional-Smooth implants (>100-fold more for post-rinse adhesion analysis). Energy-dispersive X-ray analysis indicated that the particulate material for Biocell, Microcell, and Siltex was silicone (>50%), whereas particulates from SmoothSilk and Traditional-Smooth implants were predominantly carbon-based polymers, eg, polycarbonate-urethane, consistent with packaging (and were detected on all implant types). Generally, SmoothSilk and Traditional-Smooth implant groups released >10-fold fewer particles than Biocell, Microcell, and Siltex surfaces. Pilot ex vivo tissue analysis supported these findings.

Conclusions

Particulate debris released from BIs are highly dependent on the type of implant surface and are a likely key determinant of in vivo performance.

Level of Evidence: 5
Geographical disjunction and environmental conditions drive intraspecific differentiation in the chalk-hill blue butterfly
Authors: Štefánik Martin , Habel Jan Christian , Schmitt Thomas , Eberle Jonas
Published: February 2021

Drivers of evolution are often related to geographical isolation and/or diverging environmental conditions. Spatial variation in neutral genetic markers mostly reflects past geographical isolation, i.e. long-lasting allopatry, whereas morphology is often driven by local environmental conditions, resulting in more rapid evolution. In Europe, most thermophilic species persisted during the past glacial periods in geographically disjunct refugia, representing long-lasting isolates, frequently with diverging environmental conditions. This situation has driven the evolution of intraspecific signatures in species. Here, we analysed wing shape and wing pigmentation of the chalk-hill blue butterfly, Polyommatus coridon, across its entire distribution range restricted to the western Palaearctic. In addition, we compiled abiotic environmental parameters for each sampling site. Wing colour patterns differentiated a western and an eastern lineage. These lineages might represent two main Pleistocene refugia and differentiation centres, one located on the Italian Peninsula and the other in the Balkan region. The two lineages showed evidence of hybridization across Central Europe, from the Alps and across Germany. The intraspecific differentiation was strongest in the width of the brown band on the outer margin of the wings. The morphological structures obtained are in line with genetic signatures found in previous studies, but the latter are more fine-grained. Current environmental conditions, such as mean temperatures, were only marginally correlated with colour patterns. Our study underlines that Pleistocene range shifts, often resulting in allopatric isolation, shape intraspecific phenotypic structures within species; that pigmentation responds in a more sensitive manner to spatial disjunction than wing shape; and that morphometric and genetic structures in P. coridon provide concordant patterns and thus support identical biogeographical conclusions.
Supervised exercise after oesophageal cancer surgery: the PERFECT multicentre randomized clinical trial
Authors: van Vulpen J K , Hiensch A E , van Hillegersberg R , Ruurda J P , Backx F J G , Nieuwenhuijzen G A P , Kouwenhoven E A , Groenendijk R P R , van der Peet D L , Hazebroek E J , Rosman C , Wijnhoven B P L , van Berge Henegouwen M I , van Laarhoven H W M , Siersema P D , May A M
Published: February 2021

Background

This study investigated whether a supervised exercise programme improves quality of life (QoL), fatigue and cardiorespiratory fitness in patients in the first year after oesophagectomy.

Methods

The multicentre PERFECT trial randomly assigned patients to an exercise intervention (EX) or usual care (UC) group. EX patients participated in a 12-week moderate- to high-intensity aerobic and resistance exercise programme supervised by a physiotherapist. Primary (global QoL, QoL summary score) and secondary (QoL subscales, fatigue and cardiorespiratory fitness) outcomes were assessed at baseline, 12 and 24 weeks and analysed as between-group differences using either linear mixed effects models or ANCOVA.

Results

A total of 120 patients (mean(s.d.) age 64(8) years) were included and randomized to EX (61 patients) or UC (59 patients). Patients in the EX group participated in 96 per cent (i.q.r. 92–100 per cent) of the exercise sessions and the relative exercise dose intensity was high (92 per cent). At 12 weeks, beneficial EX effects were found for QoL summary score (3.5, 95 per cent c.i. 0.2 to 6.8) and QoL role functioning (9.4, 95 per cent c.i. 1.3 to 17.5). Global QoL was not statistically significant different between groups (3.0, 95 per cent c.i. –2.2 to 8.2). Physical fatigue was lower in the EX group (–1.2, 95 per cent c.i. –2.6 to 0.1), albeit not significantly. There was statistically significant improvement in cardiorespiratory fitness following EX compared with UC (peak oxygen uptake (1.8 ml/min/kg, 95 per cent c.i. 0.6 to 3.0)). After 24 weeks, all EX effects were attenuated.

Conclusions

A supervised exercise programme improved cardiorespiratory fitness and aspects of QoL.

Trial registration

Dutch Trial Register NTR 5045 (www.trialregister.nl/trial/4942).
Cortical involvement determines impairment 30 years after a clinically isolated syndrome
Authors: Haider Lukas , Prados Ferran , Chung Karen , Goodkin Olivia , Kanber Baris , Sudre Carole , Yiannakas Marios , Samson Rebecca S , Mangesius Stephanie , Thompson Alan J , Gandini Wheeler-Kingshott Claudia A M , Ciccarelli Olga , Chard Declan T , Barkhof Frederik
Published: February 2021

Many studies report an overlap of MRI and clinical findings between patients with relapsing-remitting multiple sclerosis (RRMS) and secondary progressive multiple sclerosis (SPMS), which in part is reflective of inclusion of subjects with variable disease duration and short periods of follow-up. To overcome these limitations, we examined the differences between RRMS and SPMS and the relationship between MRI measures and clinical outcomes 30 years after first presentation with clinically isolated syndrome suggestive of multiple sclerosis. Sixty-three patients were studied 30 years after their initial presentation with a clinically isolated syndrome; only 14% received a disease modifying treatment at any time point. Twenty-seven patients developed RRMS, 15 SPMS and 21 experienced no further neurological events; these groups were comparable in terms of age and disease duration. Clinical assessment included the Expanded Disability Status Scale, 9-Hole Peg Test and Timed 25-Foot Walk and the Brief International Cognitive Assessment For Multiple Sclerosis. All subjects underwent a comprehensive MRI protocol at 3 T measuring brain white and grey matter (lesions, volumes and magnetization transfer ratio) and cervical cord involvement. Linear regression models were used to estimate age- and gender-adjusted group differences between clinical phenotypes after 30 years, and stepwise selection to determine associations between a large sets of MRI predictor variables and physical and cognitive outcome measures. At the 30-year follow-up, the greatest differences in MRI measures between SPMS and RRMS were the number of cortical lesions, which were higher in SPMS (the presence of cortical lesions had 100% sensitivity and 88% specificity), and grey matter volume, which was lower in SPMS. Across all subjects, cortical lesions, grey matter volume and cervical cord volume explained 60% of the variance of the Expanded Disability Status Scale; cortical lesions alone explained 43%. Grey matter volume, cortical lesions and gender explained 43% of the variance of Timed 25-Foot Walk. Reduced cortical magnetization transfer ratios emerged as the only significant explanatory variable for the symbol digit modality test and explained 52% of its variance. Cortical involvement, both in terms of lesions and atrophy, appears to be the main correlate of progressive disease and disability in a cohort of individuals with very long follow-up and homogeneous disease duration, indicating that this should be the target of therapeutic interventions.
Studying human nociceptors: from fundamentals to clinic
Authors: Middleton Steven J , Barry Allison M , Comini Maddalena , Li Yan , Ray Pradipta R , Shiers Stephanie , Themistocleous Andreas C , Uhelski Megan L , Yang Xun , Dougherty Patrick M , Price Theodore J , Bennett David L
Published: February 2021

Chronic pain affects one in five of the general population and is the third most important cause of disability-adjusted life-years globally. Unfortunately, treatment remains inadequate due to poor efficacy and tolerability. There has been a failure in translating promising preclinical drug targets into clinic use. This reflects challenges across the whole drug development pathway, from preclinical models to trial design. Nociceptors remain an attractive therapeutic target: their sensitization makes an important contribution to many chronic pain states, they are located outside the blood–brain barrier, and they are relatively specific. The past decade has seen significant advances in the techniques available to study human nociceptors, including: the use of corneal confocal microscopy and biopsy samples to observe nociceptor morphology, the culture of human nociceptors (either from surgical or post-mortem tissue or using human induced pluripotent stem cell derived nociceptors), the application of high throughput technologies such as transcriptomics, the in vitro and in vivo electrophysiological characterization through microneurography, and the correlation with pain percepts provided by quantitative sensory testing. Genome editing in human induced pluripotent stem cell-derived nociceptors enables the interrogation of the causal role of genes in the regulation of nociceptor function. Both human and rodent nociceptors are more heterogeneous at a molecular level than previously appreciated, and while we find that there are broad similarities between human and rodent nociceptors there are also important differences involving ion channel function, expression, and cellular excitability. These technological advances have emphasized the maladaptive plastic changes occurring in human nociceptors following injury that contribute to chronic pain. Studying human nociceptors has revealed new therapeutic targets for the suppression of chronic pain and enhanced repair. Cellular models of human nociceptors have enabled the screening of small molecule and gene therapy approaches on nociceptor function, and in some cases have enabled correlation with clinical outcomes. Undoubtedly, challenges remain. Many of these techniques are difficult to implement at scale, current induced pluripotent stem cell differentiation protocols do not generate the full diversity of nociceptor populations, and we still have a relatively poor understanding of inter-individual variation in nociceptors due to factors such as age, sex, or ethnicity. We hope our ability to directly investigate human nociceptors will not only aid our understanding of the fundamental neurobiology underlying acute and chronic pain but also help bridge the translational gap.
The Critical Need for Pooled Data on Coronavirus Disease 2019 in African Children: An AFREhealth Call for Action Through Multicountry Research Collaboration
Authors: Sam-Agudu Nadia A , Rabie Helena , Pipo Michel Tshiasuma , Byamungu Liliane Nsuli , Masekela Refiloe , van der Zalm Marieke M , Redfern Andrew , Dramowski Angela , Mukalay Abdon , Gachuno Onesmus W , Mongweli Nancy , Kinuthia John , Ishoso Daniel Katuashi , Amoako Emmanuella , Agyare Elizabeth , Agbeno Evans K , Mohammed Jibril Aishatu , Abdullahi Asara M , Amadi Oma , Mohammed Umar Umar , Ayele Birhanu T , Machekano Rhoderick N , Nyasulu Peter S , Hermans Michel P , Otshudiema John Otokoye , Bongo-Pasi Nswe Christian , Kayembe Jean-Marie N , Mbala-Kingebeni Placide , Muyembe-Tamfum Jean-Jacques , Aanyu Hellen Tukamuhebwa , Musoke Philippa , Fowler Mary Glenn , Sewankambo Nelson , Suleman Fatima , Adejumo Prisca , Tsegaye Aster , Mteta Alfred , Noormahomed Emilia V , Deckelbaum Richard J , Zumla Alimuddin , Mavungu Landu Don Jethro , Tshilolo Léon , Zigabe Serge , Goga Ameena , Mills Edward J , Umar Lawal W , Kruger Mariana , Mofenson Lynne M , Nachega Jean B ,   Investigators in the AFREhealth COVID-19 Research Collaboration on Children and Adolescents, Dasoberi Ireneous N , Sam-Woode Clara , Yeboah Georgina
Published: February 2021

Globally, there are prevailing knowledge gaps in the epidemiology, clinical manifestations, and outcomes of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection among children and adolescents; and these gaps are especially wide in African countries. The availability of robust age-disaggregated data is a critical first step in improving knowledge on disease burden and manifestations of coronavirus disease 2019 (COVID-19) among children. Furthermore, it is essential to improve understanding of SARS-CoV-2 interactions with comorbidities and coinfections such as human immunodeficiency virus (HIV), tuberculosis, malaria, sickle cell disease, and malnutrition, which are highly prevalent among children in sub-Saharan Africa. The African Forum for Research and Education in Health (AFREhealth) COVID-19 Research Collaboration on Children and Adolescents is conducting studies across Western, Central, Eastern, and Southern Africa to address existing knowledge gaps. This consortium is expected to generate key evidence to inform clinical practice and public health policy-making for COVID-19 while concurrently addressing other major diseases affecting children in African countries.
Visuospatial and Tactile Working Memory in Individuals with Congenital Deafness
Authors: Heled Eyal , Ohayon Maayan
Published: February 2021

Studies examining visuospatial working memory (WM) in individuals with congenital deafness have yielded inconsistent results, and tactile WM has rarely been examined. The current study examined WM span tasks in the two modalities among 20 individuals with congenital deafness and 20 participants with typical hearing. The congenital deafness group had longer forward and backward spans than typical hearing participants in a computerized Corsi block-tapping test (Visuospatial Span), whereas no such difference was found in the Tactual Span (tactile WM). In the congenital deafness group, age of sign language acquisition was not correlated with either condition of the visuospatial task, and Tactual and Visuospatial Spans scores were correlated in the backward but not the forward condition. The typical hearing group showed no correlation between the tasks. The findings suggest that early deafness leads to visuospatial but not tactile superiority in WM, specifically with respect to the storage component. More broadly, it appears that deafness-related compensation mechanisms in WM do not affect the other modalities in a uniform manner.
The Burden of Inflammatory Bowel Disease in Europe in 2020
Authors: Zhao Mirabella , Gönczi Lóránt , Lakatos Peter L , Burisch Johan
Published: February 2021

New data suggest that incidence and prevalence of inflammatory bowel diseases [IBD] are still increasing worldwide, and approximately 0.2% of the European population suffer from IBD at the present time. Medical therapy and disease management have evolved significantly in recent decades, with an emphasis on tight objective monitoring of disease progression and a treat-to-target approach in Europe and also worldwide, aiming to prevent early bowel damage and disability. Surgery rate declined over time in Europe, with 10–30% of CD and 5–10% of UC patients requiring a surgery within 5 years. The health economic burden associated with IBD is high in Europe. Direct health care costs [approximately €3500 in CD and €2000 in UC per patient per year] have shifted from hospitalisation and surgery towards drug-related expenditures with the increasing use of biologic therapy and other novel agents, and substantial indirect costs arise from work productivity loss [approximately €1900 per patient yearly]. The aim of this paper is to provide an updated review of the burden of IBD in Europe by discussing current data on epidemiology, disease course, risk for surgery, hospitalisation, and mortality and cancer risks, as well as the economic aspects, patient disability, and work impairment, by discussing the latest population-based studies from the region.
The Production of Inequalities within Families and across Generations: The Intergenerational Effects of Birth Order on Educational Attainment
Authors: Barclay Kieron J , Lyngstad Torkild H , Conley Dalton C
Published: February 2021

There has long been interest in the extent to which effects of social stratification extend and persist across generations. We take a novel approach to this question by asking whether birth order in the parental generation influences the educational attainment of their children. To address this question, we use Swedish population data on cohorts born 1960–1982. To study the effects of parental birth order, we use cousin fixed effects comparisons. In analyses where we compare cousins who share the same biological grandparents to adjust for unobserved factors in the extended family, we find that having a later-born parent reduces educational attainment to a small extent. For example, a second- or fifth-born mother reduces educational attainment by 0.09 and 0.18 years, respectively, while having a second- or fifth-born father reduces educational attainment by 0.04 and 0.11 years, respectively. After adjusting for attained parental education and social class, the parental birth order effect is practically attenuated to zero. Overall our results suggest that parental birth order influences offspring educational and socioeconomic outcomes through the parents own educational and socioeconomic attainment. We cautiously suggest that parental birth order may have potential as an instrument for parental socioeconomic status in social stratification research more generally.
A cohort study and meta-analysis of isolated diastolic hypertension: searching for a threshold to guide treatment
Authors: Jacobsen Alan P , Al Rifai Mahmoud , Arps Kelly , Whelton Seamus P , Budoff Matthew J , Nasir Khurram , Blaha Michael J , Psaty Bruce M , Blumenthal Roger S , Post Wendy S , McEvoy John W
Published: February 2021

Aims 

Whether isolated diastolic hypertension (IDH), as defined by the 2017 American College of Cardiology (ACC)/American Heart Association (AHA) guideline, is associated with cardiovascular disease (CVD) has been disputed. We aimed to further study the associations of IDH with (i) subclinical CVD in the form of coronary artery calcium (CAC), (ii) incident systolic hypertension, and (iii) CVD events.

Methods and results 

We used multivariable-adjusted logistic and Cox regression to test whether IDH by 2017 ACC/AHA criteria (i.e. systolic blood pressure <130 mmHg and diastolic blood pressure ≥80 mmHg) was associated with the above outcomes in the Multi-Ethnic Study of Atherosclerosis (MESA). In a random-effects meta-analysis of the association between IDH and CVD events, we combined the MESA results with those from seven other previously published cohort studies. Among the 5104 MESA participants studied, 7.5% had IDH by the 2017 ACC/AHA criteria. There was no association between IDH and CAC [e.g. adjusted prevalence odds ratio for CAC >0 of 0.88 (95% CI 0.66, 1.17)]. Similarly, while IDH was associated with incident systolic hypertension, there was no statistically significant associations with incident CVD [hazard ratio 1.19 (95% CI 0.77, 1.84)] or death [hazard ratio 0.94 (95% CI 0.65, 1.36)] over 13 years in MESA. In a stratified meta-analysis of eight cohort studies (10 037 843 participants), the 2017 IDH definition was also not consistently associated with CVD and the relative magnitude of any potential association was noted to be numerically small [e.g. depending on inclusion criteria applied in the stratification, the adjusted hazard ratios ranged from 1.04 (95% CI 0.98, 1.10) to 1.09 (95% 1.03, 1.15)].

Conclusion 

The lack of consistent excess in CAC or CVD suggests that emphasis on healthy lifestyle rather than drug therapy is sufficient among the millions of middle-aged or older adults who now meet the 2017 ACC/AHA criteria for IDH, though they require follow-up for incident systolic hypertension. These findings may not extrapolate to adults younger than 40 years, motivating further study in this age group.
Discovery of three loci increasing resistance to charcoal rot caused by Macrophomina phaseolina in octoploid strawberry
Authors: Nelson Jonathan R , Verma Sujeet , Bassil Nahla V , Finn Chad E , Hancock James F , Cole Glenn S , Knapp Steven J , Whitaker Vance M
Published: February 2021

Charcoal rot caused by Macrophomina phaseolinais an increasing economic problem in annualized strawberry production systems around the world. Currently there are no effective postfumigation chemical controls for managing charcoal rot, and no information is available on the genetic architecture of resistance to M. phaseolina in strawberry (Fragaria ×ananassa). In this study, three multiparental discovery populations and two validation populations were inoculated at planting and evaluated for mortality in three consecutive growing seasons. Genome-wide SNP genotyping and pedigree-based analysis with FlexQTL™ software were performed. Two large-effect quantitative trait loci (QTL) increasing charcoal rot resistance were discovered and validated in cultivated germplasm. FaRMp1 was located on linkage group 2A in the interval 20.4to 24.9 cM, while FaRMp2 was located on linkage group 4B in the interval 41.1to 61.2 cM. Together these QTLs explained 27% and 17% of the phenotypic variance in two discovery populations consisting of elite breeding germplasm. For both QTLs, the resistant allele showed some evidence of partial dominance, but no significant interaction was detected between the two loci. As the dosage of resistant alleles increased from 0 to 4 across the two QTLs, mortality decreased regardless of the combination of alleles.A third locus, FaRMp3 on 4D, was discovered in FVC 11–58, a reconstituted F.×ananassa originating from diverse F. virginiana and F. chiloensis accessions. This locus accounted for 44% of phenotypic variation in four segregating crosses. These findings will form the basis for DNA-informed breeding for resistance to charcoal rot in cultivated strawberry.
Of Mice and Men: Impacts of Calorie Restriction on Metabolomics of the Cerebellum
Authors: García-Flores Libia Alejandra , Green Cara L
Published: February 2021

The main purpose of research in mice is to explore metabolic changes in animal models and then predict or propose potential translational benefits in humans. Although some researchers in the brain research field have mentioned that the mouse experiments results still lack the complex neuroanatomy of humans, caution is required to interpret the findings. In mice, we observed in article seventeenth of the series of the effects of graded levels of calorie restriction, metabolomic changes in the cerebellum indicated activation of hypothalamocerebellar connections driven by hunger responses. Therefore, the purpose of the current perspective is to set this latest paper into a wider context of the physiological, behavioral, and molecular changes seen in these mice and to compare and contrast them with previous human studies.