bluuebunny/crossref_metadata_2025 huggingface dataset:
A Polyphasic Approach to Compare the Genomic Profiles of Aflatoxigenic and Non-Aflatoxigenic Isolates of Aspergillus Section Flavi
Authors: Abbas Asmaa , Hussien Taha , Yli-Mattila Tapani
Published: January 2020

Aflatoxins (AF) are highly toxic compounds produced by Aspergillus section Flavi. They spoil food crops and present a serious global health hazard to humans and livestock. The aim of this study was to examine the phylogenetic relationships among aflatoxigenic and non-aflatoxigenic Aspergillus isolates. A polyphasic approach combining phylogenetic, sequence, and toxin analyses was applied to 40 Aspergillus section Flavi isolates collected from eight countries around the world (USA, Philippines, Egypt, India, Australia, Indonesia, China, and Uganda). This allows one to pinpoint the key genomic features that distinguish AF producing and non-producing isolates. Based on molecular identification, 32 (80%) were identified as A. flavus, three (7.5%) as A. parasiticus, three (7.5%) as A. nomius and one (2.5%) as A. tamarii. Toxin analysis showed that 22 (55%) Aspergillus isolates were aflatoxigenic. The majority of the toxic isolates (62.5%) originated from Egypt. The highest aflatoxin production potential was observed in an A. nomius isolate which is originally isolated from the Philippines. DNA-based molecular markers such as random amplified polymorphic DNA (RAPD) and inter-simple sequence repeats (ISSR) were used to evaluate the genetic diversity and phylogenetic relationships among these 40 Aspergillus isolates, which were originally selected from 80 isolates. The percentage of polymorphic bands in three RAPD and three ISSR primers was 81.9% and 79.37%, respectively. Analysis of molecular variance showed significant diversity within the populations, 92% for RAPD and 85% for ISSR primers. The average of Polymorphism Information Content (PIC), Marker Index (MI), Nei’s gene diversity (H) and Shannon’s diversity index (I) in ISSR markers are higher than those in RAPD markers. Based on banding patterns and gene diversities values, we observed that the ISSR-PCR provides clearer data and is more successful in genetic diversity analyses than RAPD-PCR. Dendrograms generated from UPGMA (Unweighted Pair Group Method with Arithmetic Mean) cluster analyses for RAPD and ISSR markers were related to the geographic origin.
Electrodynamics and Radiation from Rotating Neutron Star Magnetospheres
Authors: Pétri Jérôme
Published: January 2020

Neutron stars are compact objects rotating at high speed, up to a substantial fraction of the speed of light (up to 20% for millisecond pulsars) and possessing ultra-strong electromagnetic fields (close to and sometimes above the quantum critical field of 4.4 × 10 9 T ). Moreover, due to copious e ± pair creation within the magnetosphere, the relativistic plasma surrounding the star is forced into corotation up to the light cylinder where the corotation speed reaches the speed of light. The neutron star electromagnetic activity is powered by its rotation which becomes relativistic in the neighborhood of this light cylinder. These objects naturally induce relativistic rotation on macroscopic scales about several thousands of kilometers, a crucial ingredient to trigger the central engine as observed on Earth. In this paper, we elucidate some of the salient features of this corotating plasma subject to efficient particle acceleration and radiation, emphasizing several problems and limitations concerning current theories of neutron star magnetospheres. Relativistic rotation in these systems is indirectly probed by the radiation produced within the magnetosphere. Depending on the underlying assumptions about particle motion and radiation mechanisms, different signatures on their light curves, spectra, pulse profiles and polarization angles are expected in their broadband electromagnetic emission. We show that these measurements put stringent constraints on the way to describe particle electrodynamics in a rotating neutron star magnetosphere.
Hepatitis C Virus Affects Tuberculosis-Specific T Cells in HIV-Negative Patients
Authors: El-Mokhtar Mohamed Ahmed , Elgendy Sherein G. , Eldin Abeer Sharaf , Hassan Elham Ahmed , Hasan Ali Abdel Azeem , Abdel Hameed Muhamad R. , Sayed Douaa , Salama Eman H.
Published: January 2020

The occurrence of tuberculosis (TB) and hepatitis C virus (HCV) infections in the same patient presents a unique clinical challenge. The impact of HCV infection on the immune response to TB remains poorly investigated in TB+/HCV+ patients. This study was conducted to evaluate the impact of HCV on the T-cell-mediated immune response to TB in coinfected patients. Sixty-four patients with active TB infections were screened for coinfection with HCV. The expression of immune activation markers IFN-γ, CD38, and HLA-DR on TB-specific CD4+ T cells was evaluated by flow cytometry in TB-monoinfected patients, TB/HCV-coinfected patients, and healthy controls. IL-2, IL-4, IFN-γ, TNF-α, and IL-10 levels were measured using ELISA. The end-of-treatment response to anti-TB therapy was recorded for both patient groups. Significantly lower levels of CD4+IFN-γ+CD38+ and CD4+IFN-γ+HLA-DR+ T cells were detected in TB/HCV-coinfected patients compared to TB monoinfected patients and controls. TB+/HCV+-coinfected patients showed higher serum levels of IL-10. The baseline frequencies of TB-specific activated T-cell subsets did not predict the response to antituberculous therapy in TB+/HCV+ patients. We concluded that different subsets of TB-specific CD4+ T cells in TB/HCV-infected individuals are partially impaired in early-stage HCV infection. This was combined with increased serum IL-10 level. Such immune modulations may represent a powerful risk factor for disease progression in patients with HCV/TB coinfection.
Virus Metagenomics in Farm Animals: A Systematic Review
Authors: Kwok Kirsty T. T. , Nieuwenhuijse David F. , Phan My V. T. , Koopmans Marion P. G.
Published: January 2020

A majority of emerging infectious diseases are of zoonotic origin. Metagenomic Next-Generation Sequencing (mNGS) has been employed to identify uncommon and novel infectious etiologies and characterize virus diversity in human, animal, and environmental samples. Here, we systematically reviewed studies that performed viral mNGS in common livestock (cattle, small ruminants, poultry, and pigs). We identified 2481 records and 120 records were ultimately included after a first and second screening. Pigs were the most frequently studied livestock and the virus diversity found in samples from poultry was the highest. Known animal viruses, zoonotic viruses, and novel viruses were reported in available literature, demonstrating the capacity of mNGS to identify both known and novel viruses. However, the coverage of metagenomic studies was patchy, with few data on the virome of small ruminants and respiratory virome of studied livestock. Essential metadata such as age of livestock and farm types were rarely mentioned in available literature, and only 10.8% of the datasets were publicly available. Developing a deeper understanding of livestock virome is crucial for detection of potential zoonotic and animal pathogens and One Health preparedness. Metagenomic studies can provide this background but only when combined with essential metadata and following the “FAIR” (Findable, Accessible, Interoperable, and Reusable) data principles.
Herpes Simplex Virus Type-2 Paralyzes the Function of Monocyte-Derived Dendritic Cells
Authors: Grosche Linda , Mühl-Zürbes Petra , Ciblis Barbara , Krawczyk Adalbert , Kuhnt Christine , Kamm Lisa , Steinkasserer Alexander , Heilingloh Christiane Silke
Published: January 2020

Herpes simplex viruses not only infect a variety of different cell types, including dendritic cells (DCs), but also modulate important cellular functions in benefit of the virus. Given the relevance of directed immune cell migration during the initiation of potent antiviral immune responses, interference with DC migration constitutes a sophisticated strategy to hamper antiviral immunity. Notably, recent reports revealed that HSV-1 significantly inhibits DC migration in vitro. Thus, we aimed to investigate whether HSV-2 also modulates distinct hallmarks of DC biology. Here, we demonstrate that HSV-2 negatively interferes with chemokine-dependent in vitro migration capacity of mature DCs (mDCs). Interestingly, rather than mediating the reduction of the cognate chemokine receptor expression early during infection, HSV-2 rapidly induces β2 integrin (LFA-1)-mediated mDC adhesion and thereby blocks mDC migration. Mechanistically, HSV-2 triggers the proteasomal degradation of the negative regulator of β2 integrin activity, CYTIP, which causes the constitutive activation of LFA-1 and thus mDC adhesion. In conclusion, our data extend and strengthen recent findings reporting the reduction of mDC migration in the context of a herpesviral infection. We thus hypothesize that hampering antigen delivery to secondary lymphoid organs by inhibition of mDC migration is an evolutionary conserved strategy among distinct members of Herpesviridae.
A Simple Off-Grid Incubator for Microbiological Water Quality Analysis
Authors: Bernardes Carolina , Bernardes Ricardo , Zimmer Camille , Dorea Caetano C.
Published: January 2020

There is a need for accessible and low-cost microbiological water quality testing in contexts where diarrheal illness is a major public health concern. In most cases, the quantification of Escherichia coli and other microbial indicators by conventional culture methods requires an incubation step for processed samples at specific temperatures for bacterial growth over a prescribed time. However, incubators can be the most expensive equipment required for such microbial analyses, limiting the number and scope of water quality testing available in low-resource contexts. In this study, a low-cost incubator was developed using a locally available expanded polystyrene (EPS) foam cooler, with two water bottles filled with hot water to heat incubator to a target of 35 °C. The EPS incubator performance was validated by processing 150 water samples in duplicates using the Colilert Quanti-tray/2000 system, incubated in either the EPS incubator or a standard laboratory incubator set at 35 °C. Statistically significant correlations of results indicated that the quantification of E. coli was comparable between both methods. Risk categorizations from standard and EPS incubation results agreed for 141 of 150 (94%) samples, with zero false negatives. In addition to being reasonably mobile the EPS incubator would reduce the cost of such water quality testing, thus potentially increasing the scope of water quality testing coverage.
The Wall Stress of the Capsule Surface in the Straight Pipe
Authors: Yang Xiaoni , Ma Juanjuan
Published: January 2020

Hydraulic capsule transportation is a new energy-saving transport mode. It is of great significance to the study of flow-field characteristics and pipeline-stress analysis. The purpose of this paper was to analyze the stress distribution on capsule surfaces when there is stationary in pipe flow. Results showed that the maximum shear stress on the capsule wall appeared in the rear section. Shear-stress range was between 0 and 38 Pa. Principal stress exerted great force on the capsule. The circumferential component of the principal stress was the largest, followed by the axial component, and the radial component was the smallest, i.e., σc > σa> σr. The larger the discharge of pipe flow, the greater the influence of unit discharge on wall shear stress and capsule principal stress, that is, k1 < k2< k3. Under the conditions of this experiment, the axial component of principal stress should include shear stress on the capsule, and Reynolds stress on the capsule cannot be neglected due to water-flow turbulence.
Implementing the Water Framework Directive and Tackling Diffuse Pollution from Agriculture: Lessons from England and Scotland
Authors: De Vito Laura , Fairbrother Malcolm , Russel Duncan
Published: January 2020

Tackling diffuse pollution from agriculture is a key challenge for governments seeking to implement the European Union’s Water Framework Directive (WFD). In the research literature, how best to integrate and align effective measures for tackling diffuse pollution, within the context of the EU’s multilevel governance structure, remains an open question. This paper focuses on the first and second implementation cycles of the WFD to explore how national governance arrangements either facilitated or hindered the adoption of effective policies, especially with regards to the delivery of agricultural and water policies on the ground. It draws on data collected through systematic document analysis and interviews with key experts, policymakers and interest groups, and presents a comparative analysis of two case studies: England and Scotland. The case studies show that Scotland’s joined-up governance structure, which enabled policymakers and interest groups to work together and to build trust and cooperation, facilitated the adoption of stricter measures for tackling diffuse pollution. In contrast, in England institutional fragmentation prevented a meaningful engagement of all parties and acted as a barrier. The analysis unpacks the design of policy mixes and the conditions that allow national governments to pursue more holistic and integrated governance approaches to overcome opposition from interest groups and gain their support.
Discharge Coefficients for Sluice Gates Set in Weirs at Different Upstream Wall Inclinations
Authors: Lauria Agostino , Calomino Francesco , Alfonsi Giancarlo , D’Ippolito Antonino
Published: January 2020

Laboratory experiments and numerical simulations are performed to measure discharge coefficients in the case of a gate located on the upstream wall of a weir for flood storage. The effect of the gate slope and the side contraction have been taken into account. The study was first performed experimentally, when three series of tests were carried out with (and without) a broad crested weir located under the gate, at different values of the inclination angle of the weir upstream wall, and at different values of the shape ratio and the relative opening. In order to provide useful suggestions for those involved in sluice gate construction and management, three equations were obtained based on multiple regression, relating the discharge coefficient to different parameters that characterize the phenomenon at hand, separating the case when the broad-crested weir was present. Then numerical simulations were executed by means of the Reynolds-averaged Navier–Stokes (RANS) equations with the k-ε turbulence closure model and in conjunction with the volume of fluid (VOF) method, to validate the numerical results against the experimental and to possibly investigate phenomena not caught by the experimental measurements. Simulated discharges were very close to the observed ones showing that the proposed three-dimensional numerical procedure is a favorable option to correctly reproduce the phenomenon.
Optimization and Analysis of Zeolite Augmented Electrocoagulation Process in the Reduction of High-Strength Ammonia in Saline Landfill Leachate
Authors: Hamid Mohd Azhar Abd , Aziz Hamidi Abdul , Yusoff Mohd Suffian , Rezan Sheikh Abdul
Published: January 2020

This work examined the behavior of a novel zeolite augmented on the electrocoagulation process (ZAEP) using an aluminum electrode in the removal of high-strength concentration ammonia (3471 mg/L) from landfill leachate which was saline (15.36 ppt) in nature. For this, a response surfaces methodology (RSM) through central composite designs (CCD) was used to optimize the capability of the treatment process. Design-Expert software (version 11.0.3) was used to evaluate the influences of significant variables such as zeolite dosage (100–120 g), current density (540–660 A/m2), electrolysis duration (55–65 min), and initial pH (8–10) as well as the percentage removal of ammonia. It is noted that the maximum reduction of ammonia was up to 71%, which estimated the optimum working conditions for the treatment process as follows: zeolite dosage of 105 g/L, the current density of 600 A/m2, electrolysis duration of 60 min, and pH 8.20. Furthermore, the regression model indicated a strong relationship between the predicted values and the actual experimental results with a high R2 of 0.9871. These results provide evidence of the ability of the ZAEP treatment as a viable alternative in removing high-strength landfill leachate of adequate salinity without the use of any supporting electrolyte.
Sediment Management at Run-of-River Reservoirs Using Numerical Modelling
Authors: Reisenbüchler Markus , Bui Minh Duc , Skublics Daniel , Rutschmann Peter
Published: January 2020

The worldwide storage volume of reservoirs is estimated to decrease by 0.5–1% per year due to sedimentation, which is higher than the gain in volume by newly built dams. For water supply or flood protection, the preservation of the storage volume is crucial. Operators and authorities, therefore, need sediment management concepts to ensure that the storage volume is sufficient. In this study, we developed a sediment-flushing concept using 2D numerical modelling for a run-of-river hydropower plant located in the Saalach River in southeastern Germany. The calibrated bed elevation was used as the initial bed for a number of simulations with different discharge regimes under varying operational schemes. By comparing the simulated results, we propose an appropriate flushing scheme in terms of intensity and duration to obtain a balance of sediment regime in the river. Furthermore, we demonstrate that such an optimised sediment management can generate synergies for improving measures of flood protection.
Hydrological Modeling to Assess the Efficiency of Groundwater Replenishment through Natural Reservoirs in the Hungarian Drava River Floodplain
Authors: Salem Ali , Dezső József , El-Rawy Mustafa , Lóczy Dénes
Published: January 2020

Growing drought hazard and water demand for agriculture, ecosystem conservation, and tourism in the Hungarian Drava river floodplain call for novel approaches to maintain wetland habitats and enhance agricultural productivity. Floodplain rehabilitation should be viewed as a complex landscape ecological issue which, beyond water management goals to relieve water deficit, ensures a high level of provision for a broad range of ecosystem services. This paper explores the hydrological feasibility of alternative water management, i.e., the restoration of natural reservoirs (abandoned paleochannels) to mitigate water shortage problems. To predict the efficiency of the project, an integrated surface water (Wetspass-M) and groundwater model (MODFLOW-NWT) was developed and calibrated with an eight-year data series. Different management scenarios for two natural reservoirs were simulated with filling rates ranging from 0.5 m3 s−1 to 1.5 m3 s−1. In both instances, a natural reservoir with a feeding rate of 1 m3 s−1 was found to be the best scenario. In this case 14 days of filling are required to reach the possible maximum reservoir stage of +2 m. The first meter rise increases the saturation of soil pores and the second creates an open surface water body. Two filling periods per year, each lasting for around 180 days, are required. The simulated water balance shows that reservoir–groundwater interactions are mainly governed by the inflow into and outflow from the reservoir. Such an integrated management scheme is applicable for floodplain rehabilitation in other regions with similar hydromorphological conditions and hazards, too.
The Quality of Stored Rainwater for Washing Purposes
Authors: Struk-Sokołowska Joanna , Gwoździej-Mazur Joanna , Jadwiszczak Piotr , Butarewicz Andrzej , Ofman Piotr , Wdowikowski Marcin , Kaźmierczak Bartosz
Published: January 2020

The use of rainwater for washing clothes is determined by its amount, composition and quality of washing. Raw rainwater is soft and free of pollution. The collected rainwater already contains pollution present in the atmosphere and washed away from roofs and other surfaces. It can also change its quality when stored in tanks. Washing clothes does not require drinking quality water but just clean, safe water that guarantees effective removal of dirt from fabrics. The study determined the physicochemical and microbiological changes of rainwater characteristics during retention. Rainwater was collected in a standard underground tank for 30 days and water analyses were conducted every 10 days. The possibility of tap water replacement in the household with collected rainwater for ecological clothes washing has been assessed.
Flash Flood Early Warning Coupled with Hydrological Simulation and the Rising Rate of the Flood Stage in a Mountainous Small Watershed in Sichuan Province, China
Authors: Tu Huawei , Wang Xiekang , Zhang Wanshun , Peng Hong , Ke Qian , Chen Xiaomin
Published: January 2020

Flash floods in mountainous areas have become more severe and frequent as a result of climate change and are a threat to public safety and social development. This study explores the application of distributed hydrological models in flash floods risk management in a small watershed in Sichuan Province, China, and aims to increase early warning lead time in mountainous areas. The Hydrologic Engineering Center’s Hydrologic Modeling System (HEC-HMS) model was used to simulate the flash flood process and analyze the variation in flood hydrographs. First, the HEC-HMS model was established based on geospatial data and the river network shape, and eight heavy rainfall events from 2010 to 2015 were used for model calibration and validation, showing that the HEC-HMS model was effective for the simulation of mountain floods in the study area. Second, with the assumption that rainfall and flood events have the same frequency, the flood hydrographs with different frequencies (p = 1%, 2%, 5%, and 10%) were calculated by the HEC-HMS model. The rising limbs of the flood hydrographs were significantly different and can be divided into three parts (0–5 h, 6–10 h, and 11–15 h). The rising rate of the flood stage for each part of the flood hydrograph increases in multiples. According to the analysis of the flood hydrographs, two critical early warning indicators with an invention patent were determined in the study: the flood stage for immediate evacuation and the rising rate. The application of the indicators in the study shows that it is feasible to advance the time of issuing an early warning signal, and it is expected that the indicators can offer a reference for flash flood early warning in the study area and other small watersheds in mountainous areas.
Factors Affecting Water Drainage Long-Time Series in the Salinized Low-Lying Coastal Area of Ravenna (Italy)
Authors: Giambastiani Beatrice Maria Sole , Macciocca Vito Raffaele , Molducci Mario , Antonellini Marco
Published: January 2020

The low-lying coastal area of Ravenna (North-eastern Italy), like the majority of delta and coastal zones around the world, is affected by groundwater salinization due to natural processes (such as low topography, natural land subsidence, seawater encroachment along estuaries, etc.) and anthropogenic activities (i.e., increased anthropogenic subsidence rate, sea level rise, geofluids extraction, and drainage). Among all factors causing aquifer salinization, water drainage plays an important role in lowering the hydraulic head and favouring saltwater seepage in the Ravenna coastal aquifer. A network of drainage canals and water pumping stations first allowed for the reclamation of the low-lying territory and today are fundamental to keep land and infrastructures dry and maintain effective soil depth for agriculture practices. The aim of this work is to identify and assess factors affecting water drainage long-time series (1971–2017) of the most important mechanical drainage basin in this low-lying coastal area. Statistical analyses of drainage, climate, and land use change datasets help constrain the relative weight of each single factor potentially causing an increase of water drainage through time. The results show that, among these factors, subsidence rates and seepage processes are the most significant. The data trends also indicate that the climate, especially in terms of precipitation amount and extreme events, played no important role during the studied time interval. The process of infiltration soil capacity loss due to urbanization and consequent soil sealing probably has a small secondary effect. Moreover, an increase in pumping through time will exacerbate aquifer salinization and compromise freshwater availability in the coastal area.
Quantitative Evaluation of Groundwater–Surface Water Interactions: Application of Cumulative Exchange Fluxes Method
Authors: Li Mingqian , Liang Xiujuan , Xiao Changlai , Cao Yuqing
Published: January 2020

Interactions between groundwater and surface water (GW-SW interactions) play a crucial role in the hydrological cycle; thus, the quantification of GW-SW interactions is essential. In this study, a cumulative exchange fluxes method based on mass balance theory is proposed for a stream-aquifer system. This method determines the curve of cumulative fluxes through the water balance term, which can characterize GW-SW interactions, determine the amount of exchange fluxes, and reveal the dynamic process of interactions. This method is used in a reach of the Taizi River Basin, and the GW-SW interactions observed in 2016 are categorized into seven stages and four types (natural controlled, reservoir and irrigation controlled, irrigation controlled, and irrigation hysteresis type). The natural recharge in the study reach is approximately 3.03 × 105 m3·day−1, and the increase caused by irrigation is 7.8–13.87 × 105 m3·day−1. After the irrigation stops, the impact can be sustained for 48 d with an increase of 3.03 × 105 m3·day−1. The most influential factor of the results is the runoff coefficient. The method is applicable to the stream in the plains with upstream and downstream flow monitoring data and can be used to analyze complex GW-SW interactions under the conditions of reservoir storage and agricultural irrigation. The analysis results will provide guidance for the other study of GW-SW interactions in this reach.
Quantitative Assessment of Specific Vulnerability to Nitrate Pollution of Shallow Alluvial Aquifers by Process-Based and Empirical Approaches
Authors: Fusco Francesco , Allocca Vincenzo , Coda Silvio , Cusano Delia , Tufano Rita , De Vita Pantaleone
Published: January 2020

Shallow aquifers of coastal and internal alluvial plains of developed countries are commonly characterized by the challenging management of groundwater resources due to the intense agricultural and industrial activities that determine a high risk of groundwater contamination. Among the principal origins of pollution in these areas are agricultural practices based on the amendment of soils by nitrate fertilizers, which have been recognized as one of the most severe environmental emergencies for which specific policies and regulations have been issued (e.g., EU Directive 2006/118/EC). In such a framework, the results of research aimed at assessing the specific vulnerability of shallow alluvial aquifers to nitrate fertilizer pollutants by coupled process-based and empirical approaches are here proposed. The research focused on assessing the specific vulnerability to nitrate pollution of a shallow alluvial aquifer of the Campania region (southern Italy), which was selected due to its representativeness to other recurrent hydrogeological settings occurring in alluvial plains of the region and worldwide. In this area, 1D hydro-stratigraphic models of the unsaturated zone were reconstructed and applied for simulating the transport of nitrate pollutants at the water table and estimating the associated travel times. Numerical modeling was carried out by the finite differences VS2TDI code and considered a 10-year time series of rainfall and evapotranspiration as well as typical local farming practices of nitrate fertilizer input. Results of the travel time calculated for the 1D hydro-stratigraphic models considered and at different depths were recognized as a proxy to assess the specific vulnerability to nitrate fertilizer pollution. Among the principal outcomes is an empirical multiple correlation between the travel time of the nitrate fertilizer pollutant, water table depth, and equivalent saturated hydraulic conductivity of the unsaturated zone or hydraulic resistance, which was used to assess the travel time at the distributed scale over the whole area studied as well as the related specific vulnerability. Given such results, the coupled process-based and empirical approach is proposed as generally applicable for assessing and mapping groundwater vulnerability in shallow aquifers, for which detailed stratigraphic and piezometric data are available.
ACCOUNTING THE STEEL PROFILE IN THE CALCULATIONS OF THE LOADING CAPABILITY OF STEEL-CONCRETE BEAMS
Authors: Vinogradova N.
Published: January 2020

Prefabricated monolithic floors are the best solution in terms of cost and time of work. In addition, due to the lightweight filling blocks included in the prefabricated monolithic structure, the overlap has less weight than the classic monolithic or precast slabs. Within the framework of this article, elements of prefabricated monolithic floors — reinforced concrete T-beams with a steel thin-walled profile, which is used primarily as formwork at the stage of construction and installation works, are calculated. Nevertheless, the calculation of the steel profile as an external reinforcement increases the load-bearing capacity of the beams by 50%. To assess the fact effect of the steel thin-walled profile on the strength characteristics of structural elements, experimental studies are conducted. According to the results of the experiment, it is found that the contribution of the steel thin-walled profile to the bearing capacity of the beams is 15%, while if the profile slip due to anchoring in the supporting zones is reduced, the bearing capacity increases by 50-60% compared to similar beams without a profile
MODELING THE PROCESS OF REDUCING TREE STUMPS USING SELF-PROPELLED MACHINE BASED ON THE PARTICLE DYNAMICS METHOD
Authors: Pryadkin Vladimir , Bartenev Ivan , Posmetev Viktor
Published: January 2020

The article presents an analysis of the tree dozer technologies. It is established that a separate method of grubbing out is most widespread due to the possibility of aggregation of various mounted and trailed tree dozer with wheeled and tracked tractors. Abroad, the most widespread method is simultaneous removal of the aboveground and underground parts of trees in the course of one technological operation. The main technical means of implementing direct stumping technology are self-propelled high-performance tree dozers of various capacities, and the process of tree stumping is carried out mainly with a vertically applied force. The purpose of the study was to develop a mathematical model of the process of tree stumping at a vertically applied effort based on the particle dynamics. The developed mathematical model enables to simulate soil and tree root system located in it, as well as the process of removing the tree root system, determine the vertical force applied to the tree trunk, at which feeding roots break and the main roots leave the soil. In the course of a numerical experiment, it has been found that when stumping garden trees with a diameter of 300 mm, the maximum vertical force reaches 74 kN. Due to the high physical adequacy and spatial resolution, the model enables to study the influence of the uprooting mechanism and the root system on the efficiency of stumping process.
DYNAMICS OF BIODIVERSITY OF NECTAR-BEARING RESOURCES IN THE STRUCTURE OF BIRCH FORESTS
Authors: Samsonova Irina , Do Van , Nguen Thi , Sidarenko Petr Petr
Published: January 2020

The Northwest region of Russia has a rich forage base for bees. Due to unstable weather conditions, the use of natural honey resources is complicated. The aim of the research was to determine the dynamics of biodiversity of nectar-bearing resources in the structure of birch forests. Registration sites in the birch forests of blueberry, myrtillus and myrtillus grass and under the canopy of the forest stand and at the forest edges of the Kirov Educational Experimental and Kirish Forestries of the Leningrad Region have been laid for accounting. Circular reference plots with an area of 10 m2 and a radius of 178.5 cm were used when accounting for the vegetation of the lower tier. When calculating species diversity indices, species richness indices used in biocenological studies were used. The research results have showed that the factors affecting the species composition of honey plants are the light regime under the stand canopy and biological characteristics of honey plants. The composition and number of species depends on the type of forest. According to Simpson and Margalef, grass birch is distinguished by the species diversity and richness of species. Sorrel birch forest is distinguished by the best forest ecosystem with honey species. When comparing the Sørensen coefficient for sorrel birch and grass birch, it does not exceed 0.5, which indicates the similarity of species in the experimental plots. 200 the Jacquard similarity index indicates that 25-50 % of species in the forest phytocenoses of birch forests are the same. The magnitude of the variegation of living ground cover is high in the forest edge and low in myrtillus birch wood. Thus, the species composition of the melliferous flora of the studied forest types is variable in its structure and composition
GMI Effect Sensing on Magnetic Microwires
Authors: Blažek Josef , Lipovský Pavol , Šmelko Miroslav , Draganová Katarína , Tomčo Ladislav , Ripka Pavel
Published: January 2020

One of the perspective methods for the magnetic field measurement is the methodology based on the GMI effect measurement. The improvement of the sensor is in term of the sensor sensitivity and the wide-band measurement range in comparison to the commercially available magnetometers. For the evaluation of the impedance of the sample the lock-in amplifier capable to make a decomposition of the impedance to the real and imaginary part was used. The designed and constructed measurement workstation can be used for the precise impedance measurement. Specification of the related metrological properties of the samples improve the precision of the magnetic field measurement that is important for vehicles navigation or for precise mapping of the magnetic fields if unmanned aerial vehicles are used in non-destructive archaeology.
Aircraft Gas Turbine Engine Testing
Authors: Fábry Stanislav , Spodniak Miroslav , Gašparovič Peter , Koščák Peter
Published: January 2020

The paper deals with testing of aircraft gas turbine engines. The main goal of the research is to propose and design testing sequence for a new or rebuilt engine. All factors and circumstances are described, including surroundings of the engine under test. Prerequisite knowledge is introduced, including the theory of testing, description of test beds, the methods of measurement of engine parameters and special factors that affect engine performance. Some examples of real testing facilities are mentioned. The result of the work is a proposal of test cycle, that can be modified according to engine purpose and specification.
Efectos de dieta vegetariana, sobre parámetros somáticos y hematologicos en Rattus norvegicus variedad Sprague dawley
Authors: Ramos Vizcardo Maria del Pilar , Díaz-Murillo Henry
Published: January 2020

El presente trabajo tuvo por objetivo establecer los efectos de dos dietas diferentes, omnívora y vegetariana, sobre parámetros somáticos, hematológicos en ratas de laboratorio. Se llevó a cabo en el Bioterio y Laboratorio de Fisiología Animal del Departamento de Biología de la UNSA, Arequipa, durante los meses Abril a Noviembre del 2017. Se utilizaron 24 ratas de laboratorio Rattus norvegicus, asignadas a dos grupos que se sometieron a dietas “onmívora” y “vegetariana”, respectivamente por 120 días (4 meses) donde se analizaron parámetros somáticos (peso corporal, longitud total y longitud de la cola, eritron (volúmenes corpusculares VCM, HCM, CHCM) índices leucocitarios (I. Schilling, I. Arneth, IN, IG, IR en Rattus norvegicus variedad Sprague Dawley y hemostasia (recuento de plaquetas y tiempo de protrombina) en Rattus norvegicus variedad Sprague Dawley. El peso y longitud corporal ascendieron similarmente en ambos grupos. La longitud de la cola en ambos grupos ascendió similarmente en ambos grupos pero en los tiempos de evaluación, 30, 60 y 120 días, la longitud tuvo mayor desarrollo en el grupo omnívoro (p<0.05). El eritron tiende a subir en el omnívoro. El RL no sufre variaciones significativas. El porcentaje de linfocitos tienden a ascender en ambos grupos.
Delincuencia en Bolivia desde una perspectiva espacial
Authors: Rubin de Celis Raúl , Sanjinés Tudela Gimmy Nardo , Aliaga Lordemann Javier
Published: January 2020

La delincuencia en Latinoamérica en los últimos años es tema de muchos debates, debido a su alto crecimiento experimentado en la última década. La ONU, a través del PNUD, posicionó a Latinoamérica como la región con la tasa de delincuencia más alta. Como Bolivia pertenece a esta región, es interesante ver las causas que están detrás del crecimiento de la tasa de delincuencia. Para ver las diferentes causas este documento investiga cuál es la relación entre una serie de variables explicativas y varias actividades delictivas en el país. En el documento se tratará de probar las diferentes correlaciones entre estas variables, además de que, a través de un modelo de econometría espacial, se tratará de comprobar si existe un efecto difusión o contagio entre las diferentes regiones del país.
Multiplicador del gasto público en Bolivia: una primera aproximación
Authors: Puig Jorge Pablo
Published: January 2020

Este trabajo proporciona por primera vez estimaciones empíricas sobre el multiplicador del gasto público de Bolivia, utilizando una metodología de vectores autorregresivos estructurales (SVARs). Al mismo tiempo considera la composición del gasto público según se trate de gasto corriente o gasto de capital. El gasto total sobre el producto provoca un multiplicador imperceptible en el impacto pero que rápidamente pierde soporte estadístico. La misma dinámica muestra el gasto corriente mientras que el gasto de capital tiene un multiplicador muy pequeño y estadísticamente significativo al cabo de 12 trimestres. Sobre el resto de los agregados macroeconómicos los multiplicadores estimados son pequeños y rara vez significativamente distinto de cero.
Estimación de la volatilidad del tipo de cambio en México y Brasil. Un enfoque con modelos Markov Switching Garch
Authors: Caballero Martínez Rolando , Caballero Claure Benigno
Published: January 2020

Este documento analiza la evolución de la volatilidad cambiaria en México y Brasil en el periodo 1994-2014, y presenta evidencia de que la misma tiende a disminuir con el tiempo. Además, se analiza la relación existente entre la volatilidad cambiaria y la tasa de depreciación. Nuestros hallazgos indican que tres de cinco modelos de volatilidad condicional confirman que una mayor depreciación cambiaria precede temporalmente a una mayor volatilidad cambiaria. Asimismo, para poder analizar estos efectos se emplean modelos de heterocedasticidad condicional (ARCH-M, GARCH-M, TGARCH-M, EGARCH-M, y PARCH-M), así como modelos markovianos: Switching Markov Regression. Los resultados demuestran que, una vez que la volatilidad se encuentra en un determinado régimen (alto o bajo), es muy baja la probabilidad de que pase al otro régimen de manera inmediata. Otro hallazgo importante es la persistencia alta en volatilidad en ambas economías, lo que confirmaría que los choques en ella no se disipan rápidamente.
La regulación del comercio en Bolivia: de la economía informal al mercado extralegal
Authors: Müller Juliane
Published: January 2020

Este artículo estudia el mercado de equipos electrónicos en La Paz. Se analizan los mecanismos sociales y los discursos alrededor de la regulación de la competencia y de la cooperación entre los diferentes actores, negocios familiares y empresas multinacionales. Se busca mostrar que el mercado está constituido por diversos espacios de regulación cuyos actores co-producen y aplican normas no necesariamente codificadas por el sistema jurídico. Se propone la noción de "mercado extralegal" para conceptualizar estos espacios que hacen referencia a fuentes sociales y empresariales de autoridad y legitimidad para el control de la competencia y la coordinación de las transacciones.
Reflexões sobre o conhecimento na formação de professores em comunidade de prática
Authors: Imbernón Francisco , Shigunov Neto Alexandre , Silva André Coelho da
Published: January 2020

Assumindo que a criação, a gestão e o compartilhamento do conhecimento são instrumentos primordiais da cidadania, da educação e da nova economia, objetivamos pensar questões associadas a seus processos de criação e compartilhamento no contexto da formação continuada de professores em comunidades de prática. Para isso, apoiamo-nos em noções desenvolvidas no campo da gestão do conhecimento, especialmente na chamada espiral do conhecimento. Em síntese, apontamos que uma comunidade de prática, ao proporcionar o compartilhamento dos conhecimentos tácitos dos professores, pode atuar em prol da transformação desses em conhecimentos explícitos.
Imaging in diagnostics and management of extramedullary lesions in a patient with multiple myeloma
Authors: Kozyrev Sergey , Korabelnikov Daniil , Pop Vasiliy , Troyan Vladimir , Rukavicyn Oleg
Published: January 2020

Extraosseous manifestations are found in less than 5% of patients with multiple myeloma. Involvement of the gastrointestinal system in the course of multiple myeloma (MM) is extremely rare. Imaging is required for correct staging, in the followup after treatment and is predictor of prognosis. Several imaging technologies are used for the diagnosis and management of patients with MM. Conventional radiography, computed tomography (CT), magnetic resonance imaging (MRI) and nuclear medicine imaging - positron emission tomography (PET) combined with CT (PET/CT) and PET combined with MRI (PET/MRI) are all used in clarifying the extent of bone and soft tissue lesions in MM. The brief literature review on extramedullary lesions in MM and their imaging with recommendations is given. We describe the imaging in diagnostics and management of an rare case of secondary extramedullary plasmacytoma (EMP) in relapse involving the pancreas and duodenum with the bleeding in a patient with MM, IgA lambda, stage II, after 6-years treatment with chemotherapy, autologous peripheral blood stem cell transplantation and radiotherapy. EMP was detected by PET/CT before the appearance of obvious clinical signs, and then EMP was monitoring by PET/CT, X-ray and ultrasound.
Modelo integrado de simulación y optimización para planes mineros de corto plazo en minería a cielo abierto
Authors: Orellana F. , Morales N. , Jélvez E.
Published: January 2020

Haulage system in open pit mining corresponds mainly to shovel-truck type systems, which can represent a high percentage of the operating cost of the mine. In addition, long-term open-pit mining tends to lower productivities because of deepening extraction, so improving the efficiency and productivity of the equipment is essential. However, these systems are complex to analyze, which is due both to the existing operational uncertainty and to the internal interactions that the equipment has. This paper proposes an integrated simulation and optimization model that maximizes productivity in the extraction of material, which is achieved by optimizing the dispatch of trucks during the simulation, subject to operating conditions in real time. Different dispatch strategies are presented and compared, and the results show that the use of this integrated approach translates into better operating results than deterministic methods and traditional simulation.
A Techno-Economic Assessment of the Design and Operation of a Windfarm in Europe
Authors:   School of Biological and Marine Sciences, University of Plymouth, Plymouth, United Kingdom., Prajwal K R
Published: January 2020

Offshore wind farm is a matured technology in renewable energy with continuous improvement over the years in-terms of technology. The resources are stronger and abundant compared to the land-based wind resources leading to higher wind energy capture and conversion. This paper highlights the development of offshore wind projects in Europe while addressing the design, challenges associated with the structure, maintenance, costing and decommissioning. To make the offshore farm construction and maintenance feasible coupled with reliability, different aspect of logistics and supply chain management are also reviewed in this paper.
The Effect of Promotion Mix on Consumer Decisions using Grab-Food in Palembang
Authors:   Student Magister Management, Economic Faculty of Sriwijaya Univeristy , Palembang , Indonesia., Oktari* Rizana , Wahab Zakaria ,   Lecturer of Magister management Economic Faculty, Sriwijaya University, Palembang Indonesia, Widiyanti Marlina ,   Lecturer of Magister management Economic Faculy, Sriwijaya University, Palembang Indonesia
Published: January 2020

This study is entitled The Effect of Promotion Mix on Consumer Decisions in Using Grab-Food in Palembang. The purpose of this study was to determine the effect of the promotional mix on consumer decisions in using Grab-Food in Palembang. The results showed that advertising variables (X1), sales promotion (X2), publicity (X3), direct marketing (X4) had a significant effect on consumer decisions in using Grab-Food in Palembang (Y). This is evidenced by the calculation of the F test, obtained an F-count greater than the F-table of 23,956. with Adjusted R square value of 711,440. The promotion mix consisting of advertising, sales promotion, publicity, and direct marketing together has a significant effect on consumer decisions.