bluuebunny/crossref_metadata_2025 huggingface dataset:
Mathematical modeling of steel fiber reinforced concrete properties and selecting its effective composition
Authors: Dvorkin L , Bordiuzhenko O , Zhitkovsky V , Marchuk V
Published: December 2019

Design of optimal concrete compositions with specified quality indicators at minimal cost still remains one of the most actual problems. The paper deals with methodology for designing optimal fiber reinforced concrete composition using experimental-statistical models of concrete properties. The obtained mathematical models for compressive and flexural strength of steel fiber reinforced concrete and a model of superplasticizer consumption are used. The proposed method of fiber reinforced concrete composition design takes into account the specific characteristics of the studied materials. It allows relatively easy composition optimization by applying a specific minimum cost criterion. Experimental results obtained in the frame of the study confirm efficiency of the proposed concrete mix design methodology for producing steel fiber reinforced concrete with necessary properties.
Basalt fiber concrete as a new construction material for roads and airfields
Authors: Krayushkina K , Khymeryk T , Bieliatynskyi A
Published: December 2019

The presence of reinforcing fibers in concrete in terms of their optimal content increases density, uniformity and reduces the risk of cracking which allow predicting the increased dynamic resistance, frost resistance, abrasiveness and durability of both cement and asphalt concrete. This article presents the results of experimental studies of the physical-mechanical properties of cement and asphalt concrete reinforced with basalt fiber during which technological indicators of impact on the strength and durability of concrete (fiber content in mixtures, the ratio of fiber length to the size of the largest coarse aggregate) were selected, statistical analysis and optimization of the research results. To justify the choice of basalt fiber, the results of research on the determination of its chemical composition of the fiber and physico-mechanical characteristics are shown. The optimal sizes of basalt fiber, which is introduced into the mixture, are also determined. It was concluded under what conditions the studied characteristics of concrete reinforced with basalt fiber reach their maximum value with the corresponding ratios of technological indicators.
Modified fiber reinforced concrete for industrial floors
Authors: Marushchak U D , Sydor N I , Braichenko S P , Margal I V , Soltysik R A
Published: December 2019

The main requirements to gain of strength, impact resistance without increasing brittleness, durability of concrete for industrial floors are increasing. It has been shown that the strength of concrete at the impact loads can be increased by means of regulation of the macro-, micro- and nanostructure parameters of the concrete. The kinetics of hardening, peculiarities of pore structure and impact resistance of concrete reinforced with polypropylene fiber and modified by polycarboxylate ether superplasticizer, micro- and nanofine mineral additives are investigated. Nanomodified concretes are characterized by increased rate of early strength development (fcm2/fcm28=0.55) and strength after 28 days (101.5–104.9 MPa), which meets the requirements for rapid hardening high strength concrete. Impact resistance of modified fiber reinforced concrete is determined according to special procedure, which estimate parameter of maximum weight after which the residual impression depth on the surface from impact does not exceed the permissible value (2 mm). The impact resistance of concrete modified with polycarboxylate superplasticizer is 100 and 150 N after 28 and 360 days respectively. Nanomodified fiber reinforced concrete is characterized impact resistance 200 N after 28 and 360 days.
Ash-slag binders derived from thermal power plant wastes
Authors: Pavlikov A M , Petrash O V , Popovych N M , Bondar L V
Published: December 2019

This research deals with the Portland cement hydration processes in the presence of chemical additives. The slag-alkyne binders based on bottom ash are under investigation. It has been solved the problem of utilization the wastes from the thermal power plants. The components of slag-alkyne binders have been tested, normal gravity of cement mixture with the additives has been determined, and cement mixture curing period was measured. The possibility of deriving the ash-slag binders of the thermal power plant wastes was discovered. The methods of mathematical experiment planning were applied to assess the influence levels of chemical additives on the properties of alkyne-slag binders. The presented results provide the thermal power plants with a solution to how the industrial wastes can be disposed of in an environmentally friendly fashion. The spreadsheets with research data are provided along with the equations for the binders’ properties correlation with the number of chemical additives used and its fraction in the total composition.
Polymer-cement mortar for protection of buildings against electrical influences
Authors: Pluhin O A , Plugin A M , Nesterenko S G , Plugin D A , Savchenko O M
Published: December 2019

In recent decades, the number of sudden structural failures of buildings and structures being in operation and under construction has increased in the world. Generally, most of the experts associate these failures with the following reasons: design errors; errors and violations made during construction; and poor maintenance. In our opinion, another reason for the sudden structural failure of buildings and structures and the characteristic of the areas where they occur is the periodic accumulation and alteration of excess negative electric charge and the electric field of the Earth in crust fractures zones, near artificial sources of electricity, DC powered transport, rivers and large water reservoirs. To protect buildings and structures in hazardous excess negative charge areas, a polymer-modified mortar was developed based on carbamide resin cured with chlorine iron, with the addition of a superplasticizer and fly ash from thermal power plants. Theoretical, experimental and practical results of the study are provided.
Research of influence of polymer additives-stabilizers on physical-mechanical indicators and microstructure of cement ground
Authors: Solodkyy S J , Novytskyi Y L , Topylko N I , Turba Y V
Published: December 2019

The article describes the positive effect of cement ground modification by polymer stabilizers. The influence of the latex polymer stabilizer Nanoterrasoil, manufactured by NanoSky (Germany), and the polymer acryl-based stabilizer (SAP) on the physico-mechanical parameters of a light sandy loam exposed by Portland cement stabilization has been investigated. The effect of acrylic polymer on the microstructure of the cement ground based on light sandy loam has been studied. It has been established that when introducing the polymer stabilizer Nanoterrasoil (NTS) (1-1.5 wt. %) into the cement-ground mixture with a simultaneous decrease in the cement consumption, the final product - cement ground acquires the increased compression strength (28 days) in water-saturated state and saturation coefficient. Significant increase of physico-mechanical parameters has been established even in case of loam stabilization by acrylic polymer (SAP), even without cement introduction. The cement ground modified with acrylic polymer is characterized by a solid fusion microstructure. This proves that the individual organic ions of the acrylic polymer, when introduced into the cement ground, are adsorbed on the surface of the solid particles of clay minerals, enveloping and bonding them during polymerization, forming a complex organo-mineral system.
Research of the process of spread of fire on beams of wood of fire-protected intumescent coatings
Authors: Tsapko Yu V , Yu Tsapko A , Bondarenko O P , Sukhanevych M V , Kobryn M V
Published: December 2019

The article presents the results of the protection of wooden building structures with intumescent coatings for the resistance to high-temperature flame resistance. The essence of the method of determining the effectiveness of the coating was the impact of standardized flames on fireproof wood and the definition of values. Based on the data obtained, criteria were established that correspond to the degree of damage to the specimens and the increase in the combustion temperature, resulting in a decrease in weight loss. To determine the effectiveness of fire protection in the developed coatings studies on the combustibility of wood in terms of weight loss and flue gas temperature were conducted, and it was found that with coating the degree of damage to the samples in length does not exceed 26%, the degree of damage by mass does not exceed 2% and the flue gas temperature does not exceed 115°C. However, a protective layer that is of considerable thickness to the building structure should be applied to ensure its protection, since, at a higher intensity of thermal action, the fire resistance of the wood may decrease due to the formation of a low coke layer. Full-scale tests using model specimens of wooden beams under the action of a high-temperature flame furnace have shown that the intumescent coating can withstand high temperatures, effectively preventing the penetration of heat into the material due to the formation of a swollen coke layer, which affects the speed and depth of the temperature.
Increasing the durability of fibrous cement compositions by impregnating the porous space of fiber concrete
Authors: Vandolovskyi O G , Rachkovskyi O V , Nalyvayko T A , Nalivayko T T , Gasanov A B
Published: December 2019

Fiberglass reinforcement is the most effective method of increasing the strength of concretes because fiberglass has high mechanical strength and high modulus of elasticity. The low corrosion resistance of fibers to the alkaline environment of concrete plays the role of the limiting factor to the widespread use of fiberglass reinforcement. As the process of corrosion of fiberglass largely depends on the porosity of the composition, the authors have conducted a study of the impregnation of the porous space of the fiberglass by specifically developed compound of the following composition: the liquid component – liquid glass; the neutral filler - nanodispersed silica Kovelos-05; the hardener of liquid – sodium silicofluoride. As a result of the chemical reaction between the liquid glass and the cement clinker components, colloidal calcium hydrosilicate and sodium aluminate are formed. The set of properties of liquid sodium glass enables it to accelerate the setting of concrete at the appearance of sodium aluminate and to reduce the permeability of the porous space, due to the formation of calcium hydrosilicates. These facts led to the use of liquid glass as a compound for impregnation of fiber concrete.
Application of decision–making parametric structures in the analysis of a compound planetary gear
Authors: Deptula A , Drewniak J , Macek W
Published: December 2019

The design process of planetary gears can be divided into two main stages, i.e. conceptual design and construction, that is the preparation of construction documentation. In the first stage, the constructor has a very limited number of project data. In the case of a reduction or multiplier transmission these are usually output parameters (torque and speed), characteristics of the driving and the driven machine, Therefore, the stage of gearbox design must be supported by preliminary calculations, which supports the selection of the correct technical solution, leading to the stage of the structural design preparation. In the method of systematic search, we used an algorithm for generating induction decision trees, based on entropy growth as a method related to machine learning. In the next step, the decision-making parametric structures were employed. In the future, the presented solution will allow further analyses and syntheses such as checking the isomorphism of the proposed solutions, determining the validity of constructions and/or operating parameters of the analysed gears.
Nonlinear model and simulation of a rolling bearing
Authors: Smagala A , Kecik K
Published: December 2019

This paper presents an analysis of a nonlinear model of a rolling bearing with two degrees of freedom. The acceleration response provides information regarding the relationship between vibration and a different number of balls, values of internal clearance and rotary shaft speeds. The acceleration response is higher when the radial internal clearance and the shaft speed increase. When the number of balls increases, the acceleration decreases for the entire range of radial internal clearance. These results are useful for understanding the vibration response mechanism of ball bearings under variable parameters.
Numerical analysis of the rotor in the co-simulation methodology
Authors: Siadkowska K , Raczyński R , Wendeker M
Published: December 2019

The co-simulation method in the composite analysis of the rotor enables connection between Multi Body Dynamics (MBD), Finite Element Method (FEM) and Computational Fluid Dynamics (CFD) by using MATLAB code control algorithms. The idea of unidirectional analysis assumes the use of a rigid rotor model with implemented flexible elements of specific mass-rigidity properties, a special Modal Natural Frequency matrix. In this paper, the MBD model complemented with flexible elements was loaded with inertial forces and additional aerodynamic forces. These aerodynamic forces were determined from CFD analyses considering the aeroelasticity of the rotor blade (static and dynamic characteristics appropriate for a given aerodynamic airfoil). The validation of the computational model was performed on the basis of Virtual Blade Model analyses of the rotor, completed with additional algorithms based on the Blade Element Theory method.
Modelling hydrodynamic characteristics of the underwater glider based on Computational Fluid Dynamics
Authors: Stryczniewicz K , Stryczniewicz W , Szczepaniak R
Published: December 2019

The underwater glider is buoyancy-propelled Autonomous Underwater Vehicle (AUV). Their propulsion relies upon changing their buoyancy with internal pumping systems enabling them upward and downward motion. In the presented paper, the forward gliding motions are generated by hydrodynamic lift forces exerted on a pair of hydroplanes attached to a glider hull. The hydrodynamic characteristics of a glider were determined using Computational Fluid Dynamics (CFD). A 3D model was created for the simulation of flow behaviour in the Baltic Sea. The lift and drag forces distribution at different angles of attack was studied for Reynolds number 105. The flow velocity was 0.5 m·s-1 and the angle of the attack varied from -30° to 30° in steps of 2°. Results from the CFD constitute the basis for the calculation the equations of motions of the glider in 6 degrees of freedom. The vehicle motion simulation will be achieved through numeric integration of the equations of motion. This work will contribute to dynamic modelling and three-dimensional motion simulation of the torpedo-shaped underwater glider.
Design and optimisation methods for interactive mobile VR visualisation
Authors: Skulimowski S , Badurowicz M , Barszcz M , Montusiewicz J
Published: December 2019

The article describes the process of creating a VR mobile application for Google VR platform. The application presents a virtual museum exhibition as part of cross-cultural competence and user interface usability research. The process of creating the application requires taking into account the hardware and software limitations and the specificity of mobile devices. In addition, a higher level of optimisation helps build positive user experience, which is essential in VR applications. The process includes, among others: planning activities, preparing assets, implementing VR vision and interaction modules. The paper includes descriptions of individual steps, problems and other non-standard situations that occurred during the creation and testing of the VR application. In addition the results of the initial performance tests and the methods used to optimise and maintain the stability of the application are presented. By taking into account all of the mentioned factors and the fact that many solutions are yet not well described, the description of the process is expected to provide a point of reference and help for future developers of mobile VR applications.
Neural modelling of cavitation erosion process of 34CrNiMo6 steel
Authors: Szala M , Awtoniuk M
Published: December 2019

Artificial neural networks (ANN) are commonly used to solve many industrial problems. However, their application for cavitation erosion evaluation is a quite new attempt. Thus, the aim of this work was to elaborate the neural model of the cavitation erosion process of 34CrNiMo6 steel. Cavitation erosion tests were conducted with a usage of the ultrasonic vibratory method with stationary specimen that relies on the ASMT G32 standard. The proceeding damage of marked steel surface area was observed by means of a scanning electron microscope. Wear was evaluated with profiler measurements, image analysis of cavitation worn surface areas and weighing done in stated time intervals. The cavitation erosion results were analysed with Matlab software by Neural Network Toolbox. The developed neural model of cavitation erosion process that combines exposure time, roughness, area fraction of worn surfaces, and mass loss gives promising results.
The effect of the 3D printout filling parameter on the impact strength of elements made with the FDM method
Authors: Korga S , Barszcz M , Zgryza Ł
Published: December 2019

The paper discusses the aspects of potential use of 3D printing technology in the process of manufacturing elements with different layer fillings. In 3D printing technology, the denser the percentage of filling a material, the higher the mechanical strength of a given element. However, in the literature on the subject, the dependence on these parameters for additive technology has not been unequivocally determined. Therefore, the aim of the study is to find a correlation between the internal structure of the elements understood as a percentage of filling the material produced by 3D printing technology and the impact strength achieved by these elements. To carry out the research process, sets of polymeric samples were prepared using 3D FDM printing. The shape and dimensions of the samples were determined in accordance with the PN-EN 10045-1 standard. The samples were made by means of the Printo H3 device with a closed working chamber, using ABS polymer filament. The samples were filled with a percentage interval of 10%. Impact strength tests of polymeric samples were carried out on a Charpy hammer stand adapted for this purpose. In this way, the results concerning the breaking energy were collected for particular groups of samples. The collected data allowed us to determine the relationship between the percentage of filling the sample and the energy absorbed by the sample. The results provided the basis for conclusions and recommendations regarding one of the most important technological parameters – the percentage of printed element filling.
Influence of IT outsourcing on selected groups of stakeholders (original research)
Authors: Sloniec J
Published: December 2019

This paper reports on the study conducted to determine the stakeholders of information technology outsourcing (ITO) and to the impact that IT outsourcing exerts on them. Six groups of ITO stakeholders were defined: vendor, customer, employees of supplier and customer, national labour market, national economy. In the study, employees of 200 large Polish and foreign companies operating in Poland were surveyed. The results indicated both positive and negative impact of ITO on its stakeholders: positive and negative on the customer and positive for the customer employees, which were subsequently correlated in search for conclusions The originality of the paper consists in that an extensive original study has led to defining ITO stakeholders and determining the impact of IT outsourcing on them, clarifying the positive and negative impact of ITO on customer and employees, and the correlation between the factors of the positive/negative impact of ITO on the customer. The results demonstrate that with the increase in the benefits of IT outsourcing (factors of the positive impact of outsourcing on the customer), the risks associated with it (factors of the negative impact of outsourcing on the customer) grow. This is further confirmed by a high and very high positive correlation between these values.
A cross-sectional survey of the perspectives of older people in the Scottish Highlands on the management of their chronic pain
Authors: Stewart Derek , Rushworth Gordon , Bailey Nicola , Pfleger Sharon , Jebara Tesnime , Munro Kim , Youngson Elaine , Wilson Martin , MacLeod John , Cunningham Scott
Published: December 2019

Background

Although there is evidence of suboptimal outcomes in older people with chronic pain, little emphasis has been placed on those in remote and rural settings.

Objective

To describe the perspectives of older people in the Scottish Highlands on their chronic pain management.

Design

Cross-sectional survey.

Setting

NHS Highland, the most remote and rural geographical health board in Scotland.

Subjects

Home-dwelling members of the public aged ≥70 years.

Methods

Anonymised questionnaires were mailed to a random sample of 1800 older people. Questionnaire items were demographics, nature of any chronic pain, management regimens and perceived effectiveness. Validated scales were the Pain Disability Questionnaire and the Tampa Scale for Kinesiophobia.

Results

Adjusted response rate was 39.3% (709/1755). One-quarter (25.0%, n = 177) were experiencing chronic pain, being more likely to live in deprived areas (P < 0.05). Median pain intensity was 6 (IQR 4–7, 10 high), causing distress (median 5, IQR 3–7). Respondents largely consulted GPs (66.1%, n = 117) with a minority (16.4%, n = 29) referred to a specialist pain clinic and few consulting other health professionals. Over three quarters (78.0%, n = 138) were receiving prescribed medicines, most commonly paracetamol, alone (35.6%, n = 63) or in combination with opioids (16.4%, n = 29). One-third (31.6%, n = 56) expressed a desire for more effective medicines; few reported using any non-pharmacological therapies. The median scores for the Pain Disability Questionnaire and Tampa Scale for Kinesiophobia were 74 (IQR 34–104.5, 150 high) and 40 (IQR 35–45, 68 high).

Conclusions

Evidence of provision of appropriate integrated and person-centred chronic pain care is lacking.
Associations Between Gastric Atrophy and Its Interaction With Poor Oral Health and the Risk for Esophageal Squamous Cell Carcinoma in a High-Risk Region of China: A Population-Based Case-Control Study
Authors: Ekheden Isabella , Yang Xiaorong , Chen Hui , Chen Xingdong , Yuan Ziyu , Jin Li , Lu Ming , Ye Weimin
Published: December 2019

Previous findings concerning gastric atrophy as a potential risk factor for esophageal squamous cell carcinoma (ESCC) have been inconsistent. We aimed to test whether gastric atrophy and, further, its interaction with poor oral health elevated the risk of ESCC in a high-risk region of China. Our population-based case-control study in Taixing, China (2010–2014), recruited cases from local hospitals and the local cancer registry. Controls were selected randomly from the local population registry. Ultimately, 1,210 cases and 1,978 controls answered questionnaires and provided blood samples for assay of pepsinogens. Unconditional logistic regression models were used to estimate odds ratios and 95% confidence intervals. Gastric atrophy (defined as a serum level of pepsinogen I of <55 μg/L) was associated with an increased risk for ESCC (odds ratio = 1.61; 95% confidence interval: 1.33, 1.96), even after full adjustment for potential confounding factors. In addition, suggestion of an additive interaction between gastric atrophy and poor oral health was observed (relative excess risk due to interaction = 1.28, 95% confidence interval: 0.39, 2.18). We conclude that gastric atrophy appears to be a risk factor for ESCC in a high-risk region of China, and there is a suggested additive interaction with poor oral health that increases this risk even further.
Association of Childbearing With a Short-Term Reduced Risk of Crohn Disease in Mothers
Authors: Kravdal Øystein , Magnus Per , Moum Bjørn , Høivik Marte Lie
Published: December 2019

Our aim in this study was to analyze the importance of childbearing for risk of inflammatory bowel disease. Using data from the Norwegian Population Register and the Norwegian Patient Register, we fitted discrete-time hazard models for diagnosis of Crohn disease (CD) or ulcerative colitis (UC) among men and women aged 18–81 years in 2011–2016. Year and various sociodemographic factors were controlled for. The data included 4,304 CD cases and 8,866 UC cases. Women whose youngest child was ≤4 years of age had lower CD risk the following year than childless women (odds ratio (OR) = 0.73, 95% confidence interval (CI): 0.62, 0.86). There was no such reduction in CD risk among fathers. Men whose youngest child was aged ≥20 years had higher risks of CD (OR = 1.22, 95% CI: 1.01, 1.49) and UC (OR = 1.15, 95% CI: 1.02, 1.30) than childless men. UC risk was also increased among men whose youngest child was aged ≤4 years (OR = 1.14, 95% CI: 1.02, 1.27). The short-term reduction in women’s CD risk after a birth may reflect biological effects of pregnancy. Alternatively, it may reflect residual confounding or lifestyle effects of parenthood that are of special relevance for CD in women. In particular, differences in use of oral contraceptives (which it was not possible to control for) may have contributed to the observed pattern.
Liability for Third-Party Harm When Harm-Inflicting Consumers Are Present Biased
Authors: Friehe Tim , Rößler Christoph , Dong Xiaoge
Published: December 2019

This article analyzes the workings of liability when harm-inflicting consumers are present biased and both product safety and consumer care influence expected harm. We show that present bias introduces a rationale for shifting some losses onto the manufacturer, in stark contrast with the baseline scenario in which strict consumer liability induces socially optimal product safety and precaution levels. In addition, we establish that strict liability with contributory negligence may induce socially optimal product safety and precaution choices.
Muscarinic and Nicotinic Modulation of Neocortical Layer 6A Synaptic Microcircuits Is Cooperative and Cell-Specific
Authors: Yang Danqing , Günter Robert , Qi Guanxiao , Radnikow Gabriele , Feldmeyer Dirk
Published: December 2019

Acetylcholine (ACh) is known to regulate cortical activity during different behavioral states, for example, wakefulness and attention. Here we show a differential expression of muscarinic ACh receptors (mAChRs) and nicotinic ACh receptors (nAChRs) in different layer 6A (L6A) pyramidal cell (PC) types of somatosensory cortex. At low concentrations, ACh induced a persistent hyperpolarization in corticocortical (CC) but a depolarization in corticothalamic (CT) L6A PCs via M 4 and M1 mAChRs, respectively. At ~ 1 mM, ACh depolarized exclusively CT PCs via α4β2 subunit-containing nAChRs without affecting CC PCs. Miniature EPSC frequency in CC PCs was decreased by ACh but increased in CT PCs. In synaptic connections with a presynaptic CC PC, glutamate release was suppressed via M4 mAChR activation but enhanced by nAChRs via α4β2 nAChRs when the presynaptic neuron was a CT PC. Thus, in L6A, the interaction of mAChRs and nAChRs results in an altered excitability and synaptic release, effectively strengthening CT output while weakening CC synaptic signaling.
Oscillatory Mechanisms of Successful Memory Formation in Younger and Older Adults Are Related to Structural Integrity
Authors: Sander Myriam C , Fandakova Yana , Grandy Thomas H , Shing Yee Lee , Werkle-Bergner Markus
Published: December 2019

We studied oscillatory mechanisms of memory formation in 48 younger and 51 older adults in an intentional associative memory task with cued recall. While older adults showed lower memory performance than young adults, we found subsequent memory effects (SME) in alpha/beta and theta frequency bands in both age groups. Using logistic mixed effects models, we investigated whether interindividual differences in structural integrity of key memory regions could account for interindividual differences in the strength of the SME. Structural integrity of inferior frontal gyrus (IFG) and hippocampus was reduced in older adults. SME in the alpha/beta band were modulated by the cortical thickness of IFG, in line with its hypothesized role for deep semantic elaboration. Importantly, this structure–function relationship did not differ by age group. However, older adults were more frequently represented among the participants with low cortical thickness and consequently weaker SME in the alpha band. Thus, our results suggest that differences in the structural integrity of the IFG contribute not only to interindividual, but also to age differences in memory formation.
Ideational Differences, Perception Gaps, and the Emerging Sino–US Rivalry
Authors: Chengqiu Wu
Published: December 2019

Bilateral relations between China and the United States have evolved over the past two decades from the ‘same bed, different dreams’ of the 1990s when, despite different interests and perceptions, globalisation and multilateralism drew them closer, to the potential ‘different beds, same nightmare’ scenario where their economies draw further apart and their governments are locked in hegemonic rivalry. Drawing on Wendtian constructivism and cognitive psychology, this article proposes a systematic and dynamic theoretical framework and a review of the evolution of Sino–US relations to explain how and why the above changes happened. We subdivide Sino–US relations since the early 1990s into five periods that describe the United States’ China strategy in four aspects and China’s US strategy in three aspects. Our findings are that the United States’ China strategy has changed dramatically while China’s US strategy has remained relatively stable, and that Sino–US relations from the early 1990s to mid-2010 were characterised by cooperation borne of strategic compatibility, whereas those ensuing were characterised by competition due to strategic incompatibility. We argue that rivalry between the two countries stems from their fundamentally different ideas, namely, Chinese statist nationalism and American liberal hegemony, and that gaps in perception have exacerbated the differences. Simply put, their ‘different dreams’ have led to the ‘same nightmare’.
Molecular Structure and Function of Janus Kinases: Implications for the Development of Inhibitors
Authors: Garrido-Trigo Alba , Salas Azucena
Published: December 2019

Cytokines can trigger multiple signalling pathways, including Janus tyrosine kinases [JAK] and signal transducers and activators of transcription [STATS] pathways. JAKs are cytoplasmic proteins that, following the binding of cytokines to their receptors, transduce the signal by phosphorylating STAT proteins which enter the nuclei and rapidly target gene promoters to regulate gene transcription. Due to the critical involvement of JAK proteins in mediating innate and adaptive immune responses, these family of kinases have become desirable pharmacological targets in inflammatory diseases, including ulcerative colitis and Crohn’s disease. In this review we provide an overview of the main cytokines that signal through the JAK/STAT pathway and the available in vivo evidence on mutant or deleted JAK proteins, and discuss the implications of pharmacologically targeting this kinase family in the context of inflammatory diseases.
Novel rhizobia exhibit superior nodulation and biological nitrogen fixation even under high nitrate concentrations
Authors: Nguyen Hien P , Miwa Hiroki , Obirih-Opareh Jennifer , Suzaki Takuya , Yasuda Michiko , Okazaki Shin
Published: December 2019

Legume–rhizobium symbiosis leads to the formation of nitrogen-fixing root nodules. However, externally applied chemical nitrogen fertilizers (nitrate and ammonia) strongly inhibit nodule formation and nitrogen fixation. Here, we isolated several rhizobial strains exhibiting a superior nodulation and nitrogen fixation with soybean at high nitrate concentrations. The nodulation of soybean symbiont Bradyrhizobium diazoefficiens USDA110 was significantly inhibited at 12.5 mM nitrate; however, three isolates (NKS4, NKM2 and NKTG2) were capable of forming nitrogen-fixing nodules, even at 20 mM nitrate. These isolates exhibited higher nodulation competitiveness and induced larger nodules with higher nitrogen-fixation activity than USDA110 at 5 mM nitrate. Furthermore, these isolates induced more nodules than USDA110 even in nitrate-free conditions. These isolates had a distant lineage within the Bradyrhizobium genus; though they were relatively phylogenetically close to Bradyrhizobium japonicum, their morphological and growth characteristics were significantly different. Notably, in the presence of nitrate, expression of the soybean symbiosis-related genes (GmENOD40 and GmNIN) was significantly higher and expression of GmNIC1 that is involved in nitrate-dependent nodulation inhibition was lower in the roots inoculated with these isolates in contrast with inoculation of USDA110. These novel rhizobia serve as promising inoculants for soybeans cultivated in diverse agroecosystems, particularly on nitrate-applied soils.
Arbuscular mycorrhiza has little influence on N2O potential emissions compared to plant diversity in experimental plant communities
Authors: Okiobe Simon T , Rillig Matthias C , Mola Magkdi , Augustin Jürgen , Parolly Gerald , Veresoglou Stavros D
Published: December 2019

Denitrification is an ecosystem process linked to ongoing climate change, because it releases nitrous oxide (N2O) into the atmosphere. To date, the literature covers mostly how aboveground (i.e. plant community structure) and belowground (i.e. plant-associated soil microbes) biota separately influence denitrification in isolation of each other. We here present a mesocosm experiment where we combine a manipulation of belowground biota (i.e. addition of Rhizophagus irregularis propagules to the indigenous mycorrhizal community) with a realized gradient in plant diversity. We used a seed mix containing plant species representative of mesophytic European grasslands and by stochastic differences in species establishment across the sixteen replicates per treatment level a spontaneously established gradient in plant diversity. We address mycorrhizal-induced and plant-diversity mediated changes on denitrification potential parameters and how these differ from the existing literature that studies them independently of each other. We show that unlike denitrification potential, N2O potential emissions do not change with mycorrhiza and depend instead on realized plant diversity. By linking mycorrhizal ecology to an N-cycling process, we present a comprehensive assessment of terrestrial denitrification dynamics when diverse plants co-occur.
Integrating DNA sequencing and transcriptomic data for association analyses of low-frequency variants and lipid traits
Authors: Yang Tianzhong , Wu Chong , Wei Peng , Pan Wei
Published: December 2019

Transcriptome-wide association studies (TWAS) integrate genome-wide association studies (GWAS) and transcriptomic data to showcase their improved statistical power of identifying gene–trait associations while, importantly, offering further biological insights. TWAS have thus far focused on common variants as available from GWAS. Compared with common variants, the findings for or even applications to low-frequency variants are limited and their underlying role in regulating gene expression is less clear. To fill this gap, we extend TWAS to integrating whole genome sequencing data with transcriptomic data for low-frequency variants. Using the data from the Framingham Heart Study, we demonstrate that low-frequency variants play an important and universal role in predicting gene expression, which is not completely due to linkage disequilibrium with the nearby common variants. By including low-frequency variants, in addition to common variants, we increase the predictivity of gene expression for 79% of the examined genes. Incorporating this piece of functional genomic information, we perform association testing for five lipid traits in two UK10K whole genome sequencing cohorts, hypothesizing that cis-expression quantitative trait loci, including low-frequency variants, are more likely to be trait-associated. We discover that two genes, LDLR and TTC22, are genome-wide significantly associated with low-density lipoprotein cholesterol based on 3203 subjects and that the association signals are largely independent of common variants. We further demonstrate that a joint analysis of both common and low-frequency variants identifies association signals that would be missed by testing on either common variants or low-frequency variants alone.
Primary health care patient satisfaction: Explanatory factors and geographic characteristics
Authors: Ferreira Pedro L , Raposo Vitor , Tavares Aida Isabel
Published: December 2019

Objective

To determine the factors that explain the levels of patient satisfaction and the role of geographical characteristics.

Design

Questionnaires to patients of Primary Health Care (PHC) units in Portugal Mainland distributed to each unit according to their size; codes were distributed to guarantee single responses; the questionnaire was anonymous and confidential.

Setting

Primary Health Care units in Portugal Mainland.

Participants

Primary health care patients.

Intervention(s)

None.

Main Outcome Measure(s)

Overall patient satisfaction.

Results

The main results indicate that the most significant dimension explaining overall patient satisfaction index is the satisfaction regarding general practitioner (GP) care, and the two other most significant explanatory variables of satisfaction are to be enrolled in a GP list and education. The bigger is the size of a PHC unit the lower is satisfaction. In rural areas, the level of satisfaction is higher than in urban areas. Comparing to the Lisbon metropolitan area, all other regions show a higher satisfaction in access dimension.

Conclusions

These results contribute to the creation of strategic information relevant to the evaluation of the various models of Primary Health Care, to the commissioning and definition of health policies.
Genetic Variation Among Geographically Disparate Isolates of Aster Yellows Phytoplasma in the Contiguous United States
Authors: Clements Justin , Garcia Marjorie , Bradford Benjamin , Crubaugh Linda , Piper Shannon , Duerr Emily , Zwolinska Agnieszka , Hogenhout Saskia , Groves Russell L
Published: December 2019

Aster Yellows phytoplasma (AYp; Candidatus Phytoplasma asteris) is associated with diseases of herbaceous plants, including ornamentals and important commercial vegetable and grain crops. The aster leafhopper (ALH; Macrosteles quadrilineatus Forbes) is the predominant vector of these bacteria, though other leafhopper species can acquire and transmit AYp. Potentially inoculative leafhoppers are reported to overwinter in the southern United States and migrate to northern latitudes in the spring. Examining the genetic similarities and differences in AYp associated with southern and northern populations of ALH may provide insight into the role that migrating ALH play in AYp disease development. To investigate similarities among geographically distinct populations of ALH and characterize the variation in AYp associated within these populations, we identified genetic variations in subgroup designation and the relative proportions of secreted AY-WB proteins from field-collected populations of AYp isolated from ALH from select locations in the southern (Arkansas, Kansas, Oklahoma, and Texas) and the northern United States (Wisconsin) in 2016, 2017, and 2018. Isolated phytoplasma were tested for variation of AYp genotypes, numbers of potentially inoculative (AYp-positive) ALH, and presence of specific AYp virulence (effector) genes. Geographically distinct populations of ALH collected in northern and southern regions were similar in CO1 genotype but carried different proportions of AYp genotypes. While similar AYp strains were detected in geographically distinct locations, the proportion of each genotype varied over time.
Multi-year population dynamics of a specialist trawling bat at streams with contrasting disturbance
Authors: Law Bradley , Chidel Mark , Law Peter R
Published: December 2019

Habitat degradation leads to homogenization of biological communities, often due to the dominance of generalist species over specialists. Yet data as to how life history attributes of specialists vary with such perturbations remain sparse. We compared long-term population dynamics of a specialist trawling bat, the large-footed myotis (Myotis macropus), between two forested catchments. One forest stream was nutrient-enriched from dairy farming in its headwaters and a portion of its surrounding catchment was harvested for timber during the study, while the other was located in primarily undisturbed forest. We caught and banded bats annually at their roosts over 14 years and banded 529 individuals with a 45% recapture rate. The maximum time to recapture was nine years and there was no evidence for transiency in our populations. Mark-recapture analyses allowed for investigation of the dependence of survival on time, sex, and age at marking. Our study spanned extreme El Niño and La Niña weather events, but we found little variation in survival, although recruitment was lower during drought. Mean minimum winter temperature (positive) and rainfall (positive) had weak influences on survival. Survival of adults (~0.70) and population size of adult females was similar between the two sites, suggesting that neither timber harvesting with retained riparian buffers nor eutrophication from farming influenced survival. Survival of adult males and females was similar, but survival of juveniles was less than half that of adults, probably due to a combination of mortality and dispersal. Survival was three times lower immediately after one of the timber bridges used as a roost fully collapsed. Specializing on aquatic habitats buffered M. macropus from most extreme weather, but there was also evidence for possible mortality and recovery after an intense rainfall and flooding event immediately prior to the study. More frequent intense rainfall predicted with global warming may reduce the species’ resilience over time.
Bilateral plantar fibromatosis complicated by Dupuytren’s contracture
Authors: Okano Junko , Arakawa Atsuhiro , Ogino Shuichi , Suzuki Yoshihisa
Published: December 2019

Plantar fibromatosis (PF) is a rare benign disease. Here we report bilateral PF accompanied by Dupuytren’s contracture in the right palm. Magnetic resonance imaging was useful in diagnosing PF, although biopsy was needed to rule out hemangioma. As the patient had been receiving female hormone therapy since orchiectomy, there may be a possibility that estrogen accelerated the growth of PF. Local excision with a 1-cm margin was performed, followed by primary wound closure. Neither complication nor recurrence had occurred 6 months after the surgery.
Divine (In)Corporeality in Psalms and Job
Authors: Hamilton Mark W
Published: December 2019

Several texts in Job and Psalms demonstrate an awareness of the limits of bodily metaphors for deity, even while using those metaphors as stand-ins for divine knowledge, morality, and agency. These texts work out their understanding of Yhwh’s body through contrasts with other bodies, divine or human, which are epistemically flawed, used for immoral ends, and ultimately lacking in agency. Since they predate Philo’s arguments for a disembodied God, these texts demonstrate an important step in Israel’s developing ideas about the nature of God.
Simulation of the loss-cone instability in spherical systems – I. Dominating harmonic potential
Authors: Polyachenko E V , Berczik P , Just A , Shukhman I G
Published: December 2019

A new so-called ‘gravitational loss-cone instability’ in stellar systems has recently been investigated theoretically in the framework of linear perturbation theory and proved to be potentially important in understanding the physical processes in centres of galaxies, star clusters, and the Oort Cloud. Using N-body simulations of a toy model, we confirm previous findings for the dominating harmonic potential and go beyond the linear theory. Unlike the well-known instabilities, the new one shows no notable change in the spherical geometry of the cluster, but it significantly accelerates the speed of diffusion of particles in phase space leading to an early instability saturation.
Polca SARA – full polarization, direction-dependent calibration, and sparse imaging for radio interferometry
Authors: Birdi Jasleen , Repetti Audrey , Wiaux Yves
Published: December 2019

New generation of radio interferometers are envisaged to produce high quality, high dynamic range Stokes images of the observed sky from the corresponding undersampled Fourier domain measurements. In practice, these measurements are contaminated by the instrumental and atmospheric effects that are well represented by Jones matrices, and are most often varying with observation direction and time. These effects, usually unknown, act as a limiting factor in achieving the required imaging performance and thus, their calibration is crucial. To address this issue, we develop a global algorithm, named Polca SARA, aiming to perform full polarization, direction-dependent calibration, and sparse imaging by employing a non-convex optimization technique. In contrast with the existing approaches, the proposed method offers global convergence guarantees and flexibility to incorporate sophisticated priors to regularize the imaging as well as the calibration problem. Thus, we adapt a polarimetric imaging specific method, enforcing the physical polarization constraint along with a sparsity prior for the sought images. We perform extensive simulation studies of the proposed algorithm. The results indicate the superior performance of polarization constraint based imaging when combined with the calibration of the direction-dependent effects for full Jones matrices, including their off-diagonal terms (denoting polarization leakage). The chosen priors in the proposed approach are also shown to handle the unitary ambiguity problem to a good extent.