bluuebunny/crossref_metadata_2025 huggingface dataset:
Study on emission characteristics of non-road mobile source pollutants in Tianjin
Authors: Zhang Yi , Zhou Ran , Peng Shitao , Zhang Xin , Mao Hongjun , Zhu Lequn , Li Xiaojun , Zheng Lin , Wang Yisheng
Published: April 2020

According to the collected activity level data for 2018, the emission inventory of non-road mobile sources in Tianjin was updated with the method recommended by the ministry of environmental protection. In 2018, the emissions of CO, HC, NOx, PM, and SO2 from the non-road mobile source in Tianjin were 6.72×103 t, 2.85×103 t, 3.59×104 t, 1.63×103 t, and 1.69×104 t, respectively. Among all kinds of non-road mobile sources, emissions of ship were the largest, followed by non-road mobile machinery; civil aviation aircraft and railway locomotive were relatively small. In general, emissions from non-road mobile source rose from March through November, and were relatively low at the end of each year and the beginning of the following year. The discharge of pollutants was concentrated in rural areas and counties with developed agriculture, urban center with dense population and municipal construction, port area, railway lines and airports.
Improved Fuzzy Grey Relational-TOPSIS model for hazardous waste transporter selection
Authors: Liang Xuedong , Miao Jinrui , Lu Qian
Published: April 2020

With the continuous increase of hazardous waste production, environmental protection organizations all over the world pay more attention to it, and each link of the whole life cycle of hazardous waste becomes more and more standardized. Because waste production units (WPU) must strictly abide by the law to transport hazardous waste, and most WPU do not have the relevant qualifications, plus the particularity of hazardous waste, usually choose to outsource this business, so how to choose WPU becomes more important. This paper studies the selection of hazardous waste reverse logistics suppliers. Firstly, based on the characteristics of hazardous waste industry itself, this paper innovatively establishes the evaluation and selection index system of hazardous waste transporter (HWT) from five dimensions including technical capability, service level, economic level, environment and safety and additional services. Then the fuzzy grey relational-TOPSIS (F-GR-TOPSIS) model is established by improving the grey relational-topsis model. Through the fuzzy theory, the qualitative index is quantified, and the grey relational analysis method is used to give the objective weight to the index. Finally, an example is given to verify the effectiveness of the method, which provides a certain reference for WPU to select hazardous waste transporter.
Study of the effect of weathered coal activated by ultrasonic on speciation of Cr in soil
Authors: Liu Miao , Tang Shi , Wang Guojing , Xu Yuxin , Zhang Xue
Published: April 2020

The humic acid in weathered coal contains a large number of reactive functional groups which can stably combine with heavy metal ions in the environment. This changes its biochemical stability and water solubility, reducing the migration of heavy metal ions in the soil environment to achieve the purpose of remediation of heavy metal pollution. The goal of this paper is to investigate the effects of ultrasonic activated weathered coal on the speciation of chromium (Cr) in soil and bioavailability of Cr under pakchoi cultivation. The results showed that in comparison to the control group, both the content of exchangeable, reducible and oxidizable Cr and the absorption of Cr in the soil decreased after adding weathered coal. Under the conditions of 60g/kg of ultrasonic activated weathered coal, the content of Cr absorbed by pakchoi plants was the lowest, which was 62.0% lower than that of the control group. Additionally, the content of Cr in soil reached the maximum value, which was 12.7% higher than that of the control group. Cr mainly exists as a residual state in the environment and this was 755.8% higher than that of the control group. Under the same conditions of weathered coal addition, U-WC can significantly reduce the Cr content of the weak acid extracted, reducible and oxidizable fraction in the soil, and the effective Cr content is reduced, thereby reducing Cr migration and biotoxicity in soil. This provides a theoretical basis for the application of weathered coal humic acid fertiliser in the application of weathered coal fertiliser in Cr-polluted areas.
Analysis of global upstream oil and gas assets deal characteristics and regional influencing factors
Authors: Zou Qian , Wang Keming , Yin Xiuling , Peng Min
Published: April 2020

With the sustained decline and slow recovery of international oil prices, the global upstream oil & gas deal market has witnessed significant changes since 2014. Generally, five characteristics were present: (1) shrinking deal count, (2) dominance in North America tight oil, (3) matching deals and asset optimization strategy for oil giants, (4) sluggish deals of national oil companies, and (5) active deals of small oil companies and other investors. From the regional perspective, in North America, the deals in the Permian Basin remain active; in Latin America, the deals are dominated by asset disposal and deepwater tender; in Asia-Pacific, gas-related deal count rebounded after bottoming out; in Russia-Central Asia, asset sale is subject to the domestic financial situation; in Africa, the deal count hovers at a low level; in the Middle East, the market will be open. In 2019, as the oil price rises from a stable level, the deal upsurge will unfold again, and the unconventional oil & gas industry in the United States will be continuously integrated. Then, diversified players and extensive transaction opportunities can be expected on the oil & gas market.
Can the improvement of individual well-being predict rural residents ‘choice of green cooking energy consumption? -- Evidence from CFPS 2016
Authors: Liang Min , Wang Shuai , Zhang Ying , Pongpiachan Siwatt , Sun Yan
Published: April 2020

Based on the data of CFPS2016, this paper used binary Logistic regression model and coefficient of variation weighting method to weight the subjective and objective dimensions of individual well-being, and discussed the impact of subjective and objective well-being of rural residents on green cooking energy consumption. The study found that:(1) The increase of Nagelkerke R2 reached 51.2% after adding the subjective and objective well-being variable, which indicates that well-being is of great significance in explaining rural residents ‘green cooking energy consumption behaviour.(2) The subjective well-being and objective well-being of rural populations have a significant positive predictive role in green cooking energy consumption.(3) The variation coefficient of rural residents’ subjective environmental attitudes is the highest, indicating that there is a large difference in the level of environmental attitudes among rural groups. Subsequent governments should take it as an important point to guide the improvement of the overall level of rural residents’ environmental attitudes.(4) The demographic factors, gender, age and region of rural residents have significant influence on the choice of green cooking energy consumption. The above research is helpful to understand the influencing factors of rural residents’ green cooking energy consumption behaviour from the perspective of consumers, enrich academic literature in related fields, and provide reference for other green energy consumption behaviours of rural residents in China.
Research on coordinated development of urban energy system and economic system--Based on coupling coordination model
Authors: Bi Xueyao , Niu Bingjing , Liang Xuedong , Li Congjian
Published: April 2020

Energy provides an important impetus for urban economic growth, with 80% of the world’s energy consumption concentrated in cities. With the acceleration of economic development and urbanization, China has become the world’s largest consumer of energy. Based on the data of Chengdu, China, in 2009-2018, this paper constructs an urban economicenergy evaluation index system, and uses the entropy weight method and the coupling coordination model to analyse the coordinated development between urban economic growth and energy consumption. The results show that both the energy system and the economic system can be in a coordinated development in 2008 and 2014, and the energy system and economic system are basically in an uncoordinated development in other time periods. The development process of the coupling and coordination of energy and economic systems is generally a four-stage development: coordinated - uncoordinated - coordinated - uncoordinated. Therefore, based on the above research, it is proposed to promote the simultaneous optimization and development of urban energy systems and economic systems.
Current situation and prospect of Permian Basins in the United States
Authors: Wang Keming , Zou Qian , Wang Zuoqian , Peng Min
Published: April 2020

The Permian Basin of the United States is a hot spot for global mergers and acquisitions of oil & gas assets, with the transaction value as 20% of the world’s total. Majority of participants in these activities are small and medium-sized US companies. With the decreasing costs triggered by technical advancements, more and more large oil companies have started to acquire oil and gas assets in the Permian Basin. This paper analyzed the features of M&A transactions concerning the Permian Basin, and highlighted the root causes thereof from the perspective of geologic reserves, engineering technology and surface facilities. On this basis, the future situations on the global oil markets were forecasted.
Study on technical route and business mode of electric heating in rural areas of North China
Authors: Fu Guanjun , Zheng Kuan , Zhou Jue
Published: April 2020

In 2017, after the conversion of coal to gas and coal to electricity in parts of northern rural areas, there was a shortage of gas supply and power supply, reflecting the lack of overall planning and scientific management of rural clean heating. Based on the field case analysis and research in a rural area of Hebei Province, this paper studies the technical route and business model of electric heating in rural areas of North China. The research shows that the electricity consumption per unit area in the heating season is about 53∼133kWh, the electricity cost per unit area is about 23∼45 yuan, and the initial investment of equipment are mostly more than ten thousand yuan, which is beyond the user’s tolerance. Thus the single electric heating technology is not economically viable in rural areas. This paper proposed a combined technical scheme to carry out coal-to-electricity transformation according to local economic and resource conditions, which can solve about 68% of the coal-to-electricity demand in the village. It is necessary to coordinate and plan in a unified manner, and the business model uniformly organized and implemented by integrated energy service providers has great feasibility.
Optimal portfolio strategies of purchasing electricity for electricity company based on distributional robust CVaR
Authors: Huang Xiaoyao , Wang Xiaojian , Chen Liangjin , Ye Chengjin
Published: April 2020

Considering the uncertainty of probability distribution of electricity price in multi-energy markets and taking the maximum expected profits as optimization object, this paper establishes the optimal power purchasing portfolio model based on distributional robust CVaR. An optimal portfolio problem of purchasing proportion in real-time electricity market, day-ahead electricity market, and mid-long term contract market is transformed into a semi-definite programming problem. The analysis of case study shows the efficiency of the proposed model, which paves a new way for electricity companies to determine the optimal portfolio strategies considering the risk.
Research on daily energy trading strategy of multi-microgrid on distribution side
Authors: Li Lei , Shen Yue , Ma Tiantian
Published: April 2020

This paper studies the energy trading problem between multi-micro grids on the distribution side, and proposes a multi-micro grid energy trading method based on Nash bargaining. The Nash bargaining negotiation breakpoint is the optimal operating cost for direct trading between microgrid operators and distribution operators. This paper considers the cost of over-network transmission of electrical energy in the distribution network, and builds a cooperative game model for multi-microgrid bargaining transactions. Game equilibrium solving problem is solved by genetic algorithm.
Cooperative game trading mode of virtual power plant group
Authors: Huang Feng , Lin Qingming , Zhao Zengkai , Wang Liming
Published: April 2020

Considering the complementarity of wind energy and light energy, this paper puts forward the cooperative game of virtual power plant with different clean energy output. Through real-time information exchange, the cooperative game transaction mode of virtual power plant group is proposed based on the original traditional virtual power plants directly trading with the distribution network. In the virtual power plant cooperative alliance, the virtual power plant with more electric power and the virtual power plant with less electric power could share electric power, thus obtaining higher overall profits. The nucleolus theory is used to distribute the benefits of the alliance. The validity of the model is verified by simulation.
Landscape change in the Levuvhu and Nzhelele River catchments, Venda Limpopo Province South Africa
Authors: Vessal Ali , Musakwa Walter , Malapane Olgah Lerato
Published: April 2020

Little is known regarding landscape change, although the factors and implications of such changes are evident each day. Over the past decades rapid urban sprawl, urban land expansion, agricultural intensification and expansion of renewable energy use has had a negative impact on the environment and puts the sustainability of land at risk. This paper seeks to provide knowledge on global environmental change, landscape change and climate change and to identify the drives of landscape change and their implications. Moreover, the research study aims to provide data on the drivers that influence landscape change. It seeks to provide information on how land use change and landscape change in rural areas can be affected by factors such as urbanization, climate change and human activities (rivers, agriculture, deforestation and so forth). The study shall be focused on the Levuvhu and Nzhelele river catchment area, located within the Venda Region of the Limpopo Province in South Africa. Group focus discussions, field work and interviews were conducted to collect data with environmental, geography, landscape surveyors and the local ordinary residents within the areas. The results of the findings were assessed accordingly and provided to give a clear understanding of the importance of landscape change.
Study of temperature fields in a ball bearings bodies under boundary conditions of the third kind
Authors: Popov A I , Iglin P V , Gubareva K V , Iglina T V , Doronin A S
Published: April 2020

The reliability of the rolling bearing body directly affects the continuity and duration of operation of industrial equipment. Ball bearings are often used in centrifugal pumps of thermal power plants and water supply systems. Overheating and subsequent failure of such bearings lead to failure of pumping equipment. To avoid such breakdowns, it is necessary to study the thermal processes inside the rolling elements, which can lead to their deformation and destruction. In this paper, the problems of non-stationary heat transfer inside rolling bodies (spherical bodies) are considered. An analytical solution of the problem in dimensionless values of temperatures and coordinates is obtained on the basis of Fourier and Bubnov-Galerkin methods under boundary conditions of the third kind. The solution of such a problem requires the use of an extensive mathematical apparatus, so special software tools such as Mathcad and MatLab were used in the work. So solving the problem analytically in dimensionless quantities is convenient because it allows you to scale the results to all such objects without reference to a specific rolling body. As a result, the solution is obtained in the form of a power polynomial that does not contain special functions.
Research of Thyristor Voltage Regulator Effect on Power Flows Control in Distribution Electric Networks
Authors: Kralin A A , Bedretdinov R Sh , Kryukov E V , Pronina O A
Published: April 2020

The article is devoted to the power flows redistribution process research in distribution electric networks (DEN) with thyristor voltage regulator (TVR). TVR is intended to regulate power flows and voltage stabilization in the medium-voltage network of 6-20 kV. The problems in the medium-voltage network of 6-20 kV were analyzed and solutions were determined. It was established that the key development trend of DEN is the engineering and adoption of devices based on D-FACTS technologies. In addition, we considered the features, technical characteristics and control system of TVR. The research of power flow distribution in electric system was based on a simulation model of DEN with TVR. TVR allows to regulate power flows by changing the amplitude and phase angle of the voltage, with the help of longitudinal-transverse regulation. The results have shown that the TVR allows to align load schedules, to stabilize the voltage level in complex networks with unevenly loaded nodes and to realize optimal distribution of power flows in the electrical network.
Elements realization of software-algorithmic system optimization of technological processes based on adaptive methods
Authors: Rutskov A L , Sidorenko E V , Burkovsky V L , Fedorov Ya P
Published: April 2020

The paper examines a possibility to optimize complex technological processes of energy resources transfer and consumption. Notes the importance of unidentified and weakly formalized factors consideration, which influence quality of the described object classes functioning. Suggests use of fuzzy neural networks and controllers on their basis for implementation of technological processes optimization of energy resources transfer and consumption at the expense of its dynamic accuracy forecast improvement. Presents algorithmic realization, that later on configured in the MATLAB simulated environment. Quantitative and qualitative parameters, which characterize fuzzy neural controller’s usage quality, were received. Later, software environment elements are being described, which constructed on the basis of the suggested adaptive approach for complex technological processes optimization. Points out a possibility to conduct comparative study, and also simulation modeling implementation by way of presented solutions.
Computer simulation of the operation of the device for monitoring the state of high-voltage insulators during its operation
Authors: Zaripov D K , Balobanov R N , Zakirov D F
Published: April 2020

This article presents the design and operation principle of the high-voltage isolator state indicator of the high-voltage power transmission line. The present indicator operates without the use of a separate power supply on the principle of electric field energy accumulation. The efficiency of such a device requires that as little as possible be lost during energy storage. Therefore, the development of criteria for selection of elements of the indicator circuit with minimum leakage currents is fundamental, which was one of the first tasks set during simulation. Calculations were carried out by constructing and analyzing a three-dimensional model of the insulator and solving differential equations by finite element method in the COMSOL Multiphysics software environment. The object of the study was a linear suspended insulator with polymer insulation of LK 70/35 type, designed for insulation and attachment of wires of AC overhead power transmission lines with voltage from 35 to 500 kV. Computer simulations and all calculations were made for the said insulator. On the basis of the obtained results of simulation of the insulator operation with the optical indicator installed on it, requirements to electronic components of the developed scheme were formed and corresponding components were selected.
On the need to improve the methodology for calculating energy saving and energy efficiency of enterprises
Authors: Burganov R A , Maimakova L V , Urazbakhtina L R , Golitsyna L A
Published: April 2020

Currently, the development of nanotechnology and the digital economy requires a deeper study of the basic foundations of the functioning of society and the economy, among which the production, distribution and consumption of energy of various types and forms are of particular importance. The emphasis of theoreticians and practitioners on a comprehensive review of the role of energy should be reflected in the methodology for calculating energy conservation in the production process and the provision of services. This article draws attention to the need to revise the methodology for calculating the energy saving and energy efficiency indicators of a company based on the consideration of all types of energy (energy, heat, mechanical, light, human, etc.) in the company’s activities. According to the author, a complete accounting of the energy used will optimize the costs of the company, maximize profits, and accordingly determine the development strategy of the company in the new business environment. In addition, the financial and economic performance of the company should also be updated and improved, taking into account the consumption of various forms and types of energy.
Efficiency research of free electricity (power) transfer zones integration by distributed generation
Authors: Byk F L , Myshkina L S , Terlyga N S , Frolova Y A
Published: April 2020

The possibility of combining free electricity (power) transfer zones by distributed generation is considered in this paper. The relevance of a subject is caused by the existing condition of network infrastructure and a high part of a network component in the final electricity cost, change of a fuel and energy landscape in territorial subjects of the federation, increase in ecological requirements and need of increase in power production efficiency. The object of the study is the second price zone of the wholesale market located on the territory of Siberia, where the task of increasing the availability of electricity is combined with the problem of reliable heat supply due to climatic conditions. It causes the presence of a large number of heating boiler houses. It is shown that the medium and large boiler houses transfer to the cogeneration mode of operation in the cities of the Altay Reginon and the Republic of Altai will allow to integrate the free electricity (power) transfer zones Altai and Siberia among other significant effects. Distributed generation was seen as an effective alternative to strengthening intersystem connections. It is obvious that the new network construction leads to an increase in the electricity transmission tariff and the transition to distributed generation leads to an increase in competition in retail regional markets, which reduces the cost of electricity.
Energy generation by reverse electrodialysis
Authors: Loza S A , Korzhov A N , Loza N V , Romanyuk N A
Published: April 2020

In this work, the process of generating electricity from the water salinity gradient (RED) using the Russian produced ion exchange membranes MK-40 and MA-41 was investigated. The experiments were carried out with a saturated brine of sodium chloride in a chamber with salt water and with a solution of sodium chloride with a concentration range 0.017-3.39 g/l in a chamber with fresh water. The maximum value of the specific power obtained was 0.3 W/m2. The dependence of the specific power of the salt content in the chamber with fresh water was investigated and its optimal value (0.5 – 1.5 g/l) was found. The dependence of the received power on the flow velocity in chamber with fresh water was studied. The RED process with three different RedOx systems was studied and their effect on the received power was determined. The highest power was obtained for the RedOx system of potassium ferro-ferricyanide. In case of not using the ferro-ferricyanide system leads to a significant decrease in specific power and the release of gaseous chlorine in the anode chamber.
Investigation of the effect of mixing and biomass temperature in the anaerobic digester on the volume of biomethane
Authors: Suslov D Y
Published: April 2020

The article is devoted to the study of the process of biomethane production during anaerobic fermentation in a biomethane installation. The most effective methods for increasing the efficiency of biomethane plants are to increase the intensity of mixing and the temperature of the biomass. However, currently there are various data on the optimal temperature of the fermentation process and the frequency of mixing of biomass per day. A program for conducting experimental studies and an experimental setup for producing biomethane with a bubble-type mixing system has been developed. For research, the central composite rotatable plan of the full factorial experiment was used. Experimental studies of the process of biomethane production during anaerobic fermentation of pig manure in mesophilic temperature conditions were carried out. In the process of implementing the plan, a regression equation was obtained that characterizes the effect of the bubbling mixing intensity and biomass temperature on the biomethane output. Plots of the dependence of the specific yield of biomethane on varied factors are obtained. A rational mode of operation of the biomethane plant has been established, which is achieved with a mixing intensity of 5…6 days−1 and a biomass temperature of 39.5…40.5 °C with a maximum specific yield of biomethane of 393.58 l/kg. This mode can be recommended for the operation of biomethane plants in the processing of organic waste from agricultural enterprises.
Experimental study of the silica gel drying in a fluidized bed apparatus
Authors: Nadeev A A , Barakov A V , Dubanin V Yu , Andreev A Yu , Muravev A V
Published: April 2020

In this paper, the design and principle of operation of the dryer with a centrifugal fluidized bed is considered. It is a batch apparatus with a vertical drying agent supply and is intended for drying dispersed materials with a particle diameter from 1 to 5 mm, having a high initial moisture content and a strong moisture and solid dry frame bond. Silica gel with a particle diameter from 2.2 to 2.5 mm, used for drying air and industrial gases, was used as a drying object. The scheme of the test bench is given and described. The results of an experimental study of the process of low-temperature drying of silica gel (the temperature of the drying agent ranged from 35 to 65 °C) are presented. The obtained experimental data is presented as a dependence of the thermophysical parameters of the material and the drying agent on the drying time. The comparison of drying efficiency at different modes is given. On the basis of the obtained data, a positive conclusion about the possibility of using this apparatus for low-temperature drying of capillary-porous bodies is made.
The control of lighting up regime of greenhouse plants with LED irradiators
Authors: Sheriazov S K , Popova S A , Karimov I I
Published: April 2020

A system for controlling the lighting up regime is proposed in the article, which gives the opportunity to reduce the cost of consumed electricity. The main element of the proposed control system is a processor, which calculates the necessary power of LED irradiators and the lighting up regimes according to a specially programmed program. For selecting the power and the regime of radiation of a given spectrum, a mathematical model of the geometry of the plant stalk in the process of its growth, obtained from the experimental data, is given. A two-factor experiment was carried out to determine the quantitative effect of the red and blue spectra emitted by LED sources on the geometry of the formed stalk of seed potatoes. The paper presents the results of the experimental studies on a genetically homogeneous material of potatoes grown from meristematic cells, making it possible to obtain reliable responses to different spectral composition of blue and red radiation of LED irradiators. The given system of controlling the lighting up regime allows growing the healthy plants in optimal photosynthesis with the minimal costs of electricity.
The processing of kieselguhr sludge with obtaining a new end product as reserve for reducing resources consumption of vegetable oil manufacture
Authors: Starostina I V , Porozhnyuk E V , Stolyarov D V
Published: April 2020

The article presents the research findings of processing kieselguhr sludge – a waste product of refined sunflower oil production, generated at winterization stage, when vegetable waxes, waxlike substances and other components, which crystallize at low temperatures and cause the oil turbidity, are removed. The resulting waste product is a slow stock of organomineral composition with organic matter content 65-70%. This sludge is virtually not recycled, but dumped at municipal solid waste disposal sites. This results in the environment pollution and non-recoverable losses of high-quality mineral stock and valuable organic components. It has been determined that after thermal modification of sludge waste the organic substances in it are partially oxidized with the formation of carbon layer on the surface of diatomite particles. The resulting product is a thermally modified kieselguhr sludge, which is characterized with mesoporous structure, high water repellency, and oil-receptivity and can be used as an adsorption material for purifying wastewaters from emulsified petroleum products in dynamic conditions. The secondary use of kieselguhr sludge would allow reducing the amounts of waste accumulation and improving the efficiency of raw material resources utilization.
Theoretical and experimental research on pre-sowing seed treatment
Authors: Vasilyev A A , Vasilyev A N , Dzhanibekov A K , Samarin G N , Normov D A
Published: April 2020

Grain is a biological object, with all specific responses to external actions, that reside in this category. To define principles that are needed for pre-sowing seed treatment, possible seed responses to external actions were examined. For this, the analysis of the seed’s adaptive response was used as an approach. Main rules to organize seeds stimulus have been established. Use of an informational approach for analysis of bio-logical seed response on external action allowed to find utilizing rules for electrophysical stimulation during a pre-sowing treatment. The idea behind them is to use the following sequence of operations at the pre-sawing seeds treatment: determine the lowest external action energetic at which grains response; organize cyclical action of external factor on seeds; change of action amplitude in each cycle; change of external action type. Field experiments have been conducted for several years, during which were determined operational modes of aerated grain bin electrical equipment, when used for pre-sowing seed treatment.
The protected tree Dimorphandra wilsonii (Fabaceae) is a population of inter-specific hybrids: recommendations for conservation in the Brazilian Cerrado/Atlantic Forest ecotone
Authors: Muniz André Carneiro , Lemos-Filho José Pires , Souza Helena Augusta , Marinho Rafaela Cabral , Buzatti Renata Santiago , Heuertz Myriam , Lovato Maria Bernadete
Published: April 2020

Backgrounds and Aims

Dimorphandra wilsonii Rizzini, a critically endangered and protected tree, has a restricted distribution in the ecotone between the Cerrado and the Atlantic Forest in south-eastern Brazil. In this area, it co-occurs with D. mollis Benth., a common tree from the Cerrado, and D. exaltata Schott., a rare tree from the Atlantic Forest. Previous studies of D. wilsonii indicated heterozygosity excess at the individual level. Field observation of some intermediate phenotypes between D. wilsonii and both congeners suggests hybridization of D. wilsonii with D. mollis and/or D. exaltata. Here, we tested the hypothesis that D. wilsonii may have originated from hybridization between D. exaltata and D. mollis. We also performed cytogenetic analysis to examine if the heterozygosity excess could be explained by polyploidy in D. wilsonii.

Methods

We evaluated the genetic diversity and population structure of D. wilsonii using 11 nuclear simple sequence repeats (SSRs) genotyped in 152 individuals sampled across the taxon’s range. We performed comparative genetic analyses using overlapping SSR markers between D. wilsonii and previously published SSR data in D. mollis and D. exaltata to subsequently perform a series of allelic comparisons, multivariate and Bayesian analysis.

Key Results

Our results suggest that D. wilsonii individuals are most likely to correspond to F1 hybrids between D. exaltata and D. mollis. Cytogenetic analysis indicated that D. wilsonii is diploid with the same chromosome number as D. mollis (2n = 2x = 28).

Conclusions

Our study raises questions about the taxonomic status and the evolutionary future of D. wilsonii. We suggest that the conservation and management strategy for D. wilsonii should be revised and that it should take into account both parental Dimorphandra species in the ecotone, with special emphasis on the threatened D. exaltata. Finally, this study highlights the value of genetic information for the design of conservation strategies.
Understanding and managing suicide risk
Authors: Zortea Tiago C , Cleare Seonaid , Melson Ambrose J , Wetherall Karen , O’Connor Rory C
Published: April 2020

Background

Suicidal behaviours and non-suicidal self-harm (NSSH) are global public health concerns that affect millions of lives.

Sources of data

This review is a narrative synthesis of systematic reviews, meta-analyses of randomized control trials (RCTs) and landmark studies published in scientific journals.

Areas of agreement

Restricting access to lethal means reduces the likelihood of future suicide deaths.

Areas of controversy

Our ability to predict future suicidal behaviour is no better than chance. No individual risk prediction instrument offers sufficient sensitivity and specificity to inform clinically useful decision-making.

Growing points

Different types of psychosocial interventions may be effective in preventing future suicide attempts; such interventions include clinical assessment, tailored crisis response and safety plans and follow-up contact.

Areas timely for developing research

Whilst some psychosocial interventions can be effective in reducing suicide risk, little is known about the mechanisms of recovery from suicidal thoughts and behaviours.
Association Between Improved Mobility and Distal Health Outcomes
Authors: Shuman Valerie , Coyle Peter C , Perera Subashan , Van Swearingen Jessie M , Albert Steve M , Brach Jennifer S
Published: April 2020

Background

We examined the association between improved mobility and distal health outcomes in older adults using secondary analysis of data from a cluster-randomized controlled group exercise trial.

Methods

Participants were 303 men and women aged ≥65 and older in 32 independent living facilities, senior apartments, and community centers who participated in 12-week group exercise interventions. Included were those who completed ≥1 follow-up phone call regarding outcomes assessment in the following year. Gait speed and 6-minute walk distance (6MWD) were assessed at baseline and immediately after 12-week interventions to determine mobility performance change status. Falls, emergency department (ED) visits, and hospitalizations were assessed monthly for 12 months following the end of interventions via interactive voice response phone calls. Incident rate ratios (IRRs) were calculated to quantify incidence of adverse outcomes with respect to mobility performance change.

Results

Each 0.05 m/s increase in gait speed resulted in an 11% reduction in falls (IRR = 0.89; 95% confidence interval [CI], 0.84–0.94; p < .0001); a similar decrease was seen for each 20 m increase in 6MWD (IRR = 0.89; 95% CI, 0.83–0.93; p = .0003). Those who improved gait speed had 61 falls per 1,000 person-months versus 135 in those who had no change/a decline. Those who improved 6MWD had 67 falls per 1,000 person-months versus 110 per 1,000 person-months in those who had no change/a decline. Differences in ED visits and hospitalizations were not statistically significant.

Conclusion

Improvements in mobility performance are associated with lower incidence of future falls. Given the exploratory nature of the findings, further investigation is warranted.
Different gene expression profiles in iPSC-derived motor neurons from ALS8 patients with variable clinical courses suggest mitigating pathways for neurodegeneration
Authors: Oliveira Danyllo , Morales-Vicente David A , Amaral Murilo S , Luz Livia , Sertié Andrea L , Leite Felipe S , Navarro Claudia , Kaid Carolini , Esposito Joyce , Goulart Ernesto , Caires Luiz , Alves Luciana M , Melo Uirá S , Figueiredo Thalita , Mitne-Neto Miguel , Okamoto Oswaldo K , Verjovski-Almeida Sergio , Zatz Mayana
Published: April 2020

Amyotrophic lateral sclerosis type 8 (ALS8) is an autosomal dominant form of ALS, which is caused by pathogenic variants in the VAPB gene. Here we investigated five ALS8 patients, classified as ‘severe’ and ‘mild’ from a gigantic Brazilian kindred, carrying the same VAPB mutation but displaying different clinical courses. Copy number variation and whole exome sequencing analyses in such individuals ruled out previously described genetic modifiers of pathogenicity. After deriving induced pluripotent stem cells (iPSCs) for each patient (N = 5) and controls (N = 3), motor neurons were differentiated, and high-throughput RNA-Seq gene expression measurements were performed. Functional cell death and oxidative metabolism assays were also carried out in patients’ iPSC-derived motor neurons. The degree of cell death and mitochondrial oxidative metabolism were similar in iPSC-derived motor neurons from mild patients and controls and were distinct from those of severe patients. Similar findings were obtained when RNA-Seq from such cells was performed. Overall, 43 genes were upregulated and 66 downregulated in the two mild ALS8 patients when compared with severe ALS8 individuals and controls. Interestingly, significantly enriched pathways found among differentially expressed genes, such as protein translation and protein targeting to the endoplasmic reticulum (ER), are known to be associated with neurodegenerative processes. Taken together, the mitigating mechanisms here presented appear to maintain motor neuron survival by keeping translational activity and protein targeting to the ER in such cells. As ALS8 physiopathology has been associated with proteostasis mechanisms in ER–mitochondria contact sites, such differentially expressed genes appear to relate to the bypass of VAPB deficiency.
New Kaposi’s sarcoma-associated herpesvirus variant in men who have sex with men associated with severe pathologies
Authors: Jary Aude , Leducq Valentin , Desire Nathalie , Petit Héloïse , Palich Romain , Joly Véronique , Canestri Ana , Gothland Adélie , Lambert-Niclot Sidonie , Surgers Laure , Amiel Corinne , Descamps Diane , Spano Jean-Philippe , Katlama Christine , Calvez Vincent , Marcelin Anne-Geneviève
Published: April 2020

Background

Kaposi sarcoma (KS)–associated herpesvirus (KSHV) subtype depends mostly on patient origin. The current study aimed to assess KSHV diversity in a population of men who have sex with men (MSM) living in France.

Methods

The study included 264 patients. In 65 MSM, including 57 human immunodeficiency virus (HIV)–infected men with KS, multicentric Castleman disease, or primary effusion lymphoma and 8 HIV-uninfected men receiving HIV preexposure prophylaxis (PrEP), we performed KSHV typing with K1 open reading frame Sanger and KSHV whole-genome sequencing. In 199 other patients, we performed real-time polymerase chain reaction screening for the new variant.

Results

We found that 51% of KSHV-strains were subtype C (85% C3), and 33% were subtype A. Four patients with severe KSHV disease (2 with visceral KS, 1 with multicentric Castleman disease, and 1 with primary effusion lymphoma) and 1 asymptomatic PrEP user had a new variant resembling the Ugandan subtype F, but with different K1 open reading frame and KSHV whole-genome sequences and a different epidemiological context (MSM vs African population). Its prevalence was 4.5% in Caucasian MSM, and it was absent in other epidemiological groups.

Conclusions

Subtype C predominated among MSM living in France. The new F variant was identified in Caucasian MSM and associated with severe KSHV disease, suggesting that subtype F could be split into F1 and F2 variants. Careful screening for this variant may be required in MSM, given the severe clinical presentation of associated diseases.
Householders’ perception about sustaining the useful life of long-lasting insecticide-treated nets in Ghana
Authors: Opoku Robert , Amoah Padmore Adusei , Nyamekye Kingsley Atta
Published: April 2020

Background

This article explores the multifaceted perceptions among householders about the care, efficacy and disposal of long-lasting insecticide-treated nets (LLINs), especially those regarding the end of the useful life of LLINs, and their implications for malaria control.

Methods

We used a cross-sectional qualitative design. Data were gathered in the Shai-Osudoku District in the Greater Accra Region of Ghana using focus group discussions and in-depth interviews. A thematic analysis technique was applied to analyse the data.

Results

Four findings emerged. First, participants were familiar with LLINs and the issues concerning the end of their useful life. However, the application of this knowledge was deficient. Second, characteristics of effectiveness (e.g. torn beyond repair) other than the age of a net determined the end of the useful life of LLINs. Third, social desirability and other social practices had positive and negative influences on perceptions about LLIN use and the end of their useful life. Fourth, repurposing of LLINs signified the end of their useful life.

Conclusions

Policies and strategies to position LLIN use as the leading resource for malaria control need to be innovative to accommodate the perceptions and practices of targeted households.
Reimagining EUrope through the Governance of Migration
Authors: Stierl Maurice
Published: April 2020

In its own narrative, EUrope conceives of itself as a postnational and transborder project, often through tropes of movement and the transgression of borders. In light of this imaginary, recent mass migrations provoked a serious conundrum. How would the EUropean polity reconcile the dominant idea of itself with its desire to erect barriers to cross-border movements from the “Global South”? This article inquires into tensions between, first, Hungary and, second, Italy vis-à-vis the European Commission and other EU member states over the control and regulation of unauthorized migrations in 2015 and 2018. Both examples allude to divergent and conflictual ways of governing migration, often associated with different levels of governance, particularly the supranational and the national, and different values, particularly those of tolerance and intolerance vis-à-vis the “migrant other.” While the illusion of “EUropean” and “un-EUropean” ways of governing migration is meant to be kept intact, not least through a recoding of antimigrant violence, a closer look reveals the deep entanglement of forms of migration governance that has given rise to a thoroughly EUropean border regime. This article points to the need to develop a new conceptual vocabulary in order to capture the EUropeanness of the border.
Plural and Porous: Reconceptualizing the Boundaries of Mobile Messaging Group Chats
Authors: Mannell Kate
Published: April 2020

In the nascent literature on mobile messaging groups—commonly referred to as “group chats”—there is a tendency to see them as clearly bounded units of interaction with highly-defined borders. While valuable at times, this approach does not fully reflect how group chat boundaries are experienced by the people who encounter them. Accordingly, this article aims to broaden the terms on which group chats are understood by reconceptualizing their boundaries. In doing so, it draws on interviews with 40 young adults about their friendship-based group chats and focuses, in particular, on the experiences of one participant, Matthew, who provided an especially rich account of his overlapping group chats. On the basis of this data, the article argues that the boundaries of group chats are often plural and porous, and that broader approaches to the study of group chats are needed to capture this complexity.
Potential Distribution of Nysius simulans (Hemiptera: Lygaeidae) in Soybean Crops in South America Under Current and Future Climate
Authors: de Paula Alexandre Silva , Barreto Carlos
Published: April 2020

Nysius simulans (Stål) is a suctorial, fluid feeding herbivore that can transmit toxins and spread pathogens via saliva and is an economically important pest for soybean in South America. Currently, N. simulans in soybean is predominantly found in Argentina, but future changes in the distribution from both dispersal and range shifts due to climate change may affect soybean cultivation in southern South America. We developed a species distribution model to examine the distribution range of N. simulans. We compared the potential distribution of N. simulans under current and future projected climatic conditions in order to identify future areas of natural occurrence with ecological niche models using Maxent. Current records of N. simulans show that while the species is present in Argentina, and some areas of Brazil, Paraguay, Peru, and Uruguay, our models suggest that many new suitable areas will be available for N. simulans under climate change including other regions of Argentina, and southern Chile. Our results also predict potential future range shifts and distributions into Bolivia, but not Peru nor Brazil. In our model, seasonal trends in temperature were shown to have the greatest contribution to the potential distribution, whereas isothermality (i.e., temperature variability) was correlated to potential future distribution ranges. We conclude that current populations of N. simulans may be expanding its distribution range by diffusion (i.e., range expansion over generations at the margins of populations), and regions with potential future N. simulans distribution should be closely monitored.