bluuebunny/crossref_metadata_2025 huggingface dataset:
Metaheuristic‐based optimal 3D positioning of UAVs forming aerial mesh network to provide emergency communication services
Authors: Gupta Manali , Varma Shirshu
Published: February 2021

The optimal placement of unmanned aerial vehicles (UAVs) to facilitate post‐disaster emergency communication services is a paramount research domain. The novelty of the authors’ work is to optimally place available UAVs in 3D space to meet the objectives prominent during such situations. The objectives considered here are target coverage, QoS, energy consumption and two newly characterized objectives, i.e. equal load distribution over UAVs and fault tolerance for improving network connectivity and lifetime. To improve these conflicting objectives altogether, the authors proposed two metaheuristic‐based hybrid optimization algorithms, namely, HWWO‐HSA, a hybrid of Water Wave Optimization (WWO), Harmony Search (HS) and Simulated Annealing (SA); and HGA‐SA, a hybrid of Genetic Algorithm (GA) and SA. Furthermore, to improve network performance, the authors performed their parameter tuning using well‐known Taguchi's design of experiment. For maintaining network connectivity, the authors used the concept of graphs for connected components. The proposed hybrids are compared with their originals, i.e. GA, HS, SA and WWO over different scaled test scenarios. The non‐parametric Kruskal–Wallis test and Dunn's post hoc test suggest that hybrids perform better than the originals. HGA‐SA significantly outperforms in small‐scale scenarios while HWWO‐HSA significantly outperforms in medium‐scale and large‐scale scenarios. However, being hybrid the computational time of the hybrids is greater than the originals.
Economic efficiency of oilseed production in Ukraine
Authors: Slobodianyk Anna , Abuselidze George , Lymar Valeriia
Published: February 2021

The paper studies the dynamics of the relative production efficiency of the main agricultural crops in Ukrainian enterprises for 2017 – 2019 years, in particular sunflower. It has been established that price instability restrains the intensification at which oilseed yield increases, but the degree of risk increases due to the simultaneous trend of convergence of price indicators and production costs. It is concluded that the capacity building of the oil and fat industry should have scientifically sound limits. The work is innovative in terms of its approaches and recommendations, as well as in a new perspective of researching topics. The issues and provisions given in it may be used to analyze existing theoretical positions. In addition, the theoretical significance of the paper is it can become a motif and a major base for further studies in the given direction. The practical implementation of the conclusions, recommendations and suggestions obtained from the research will contribute to the stability of oilseed production after the Covid-19 pandemic.
Environmental management and social marketing: a bibliometric analysis
Authors: Letunovska Nataliia , Lyuolyov Oleksii , Pimonenko Tetyana , Aleksandrov Vadym
Published: February 2021

The primary purpose of this study is to analyze the structure and dynamics of scientific publications in the field of environmental management and social marketing in their relationship. The authors analyzed the original keywords in the field of environmental management and social marketing. They carried out the analysis of works in the Scopus scientometric database with the subsequent use of the analytics built in the database, as well as modern software for bibliometric analysis VOSviewer and SciMAT. This study included many papers published in seven languages in the field of economics and ecology (also taking into account works from the interdisciplinary category to more fully include all possible papers). Library analysis has revealed the popularity of the use of these categories with authors from different countries with research over the years. Listed six clusters of a collaboration of countries by co-authorship. The journals with the most massive citations of the analyzed categories are listed. There is a stable dynamics of the number of studies in these categories in the subperiod 2011-2016. However, current trends until 2020 show that the popularity of research, and most importantly, their relevance will remain at the peak in subsequent years. The study may be the basis for further research in the use of marketing principles to deepen the theory of environmental management.
Environmental management and green brand for sustainable entrepreneurship
Authors: Starchenko Luidmula , Lyeonov Serhiy , Vasylieva Tetyana , Pimonenko Tetyana , Lyulyov Oleksii
Published: February 2021

The increasing competitiveness at the global market and reinforcing the ecological issues contribute the reorientation from the traditional to the sustainable business model. In this case, the business should develop the green brand of the company, which required the implementation of environmental management. The hypothesis of the paper is checking the linking between environmental management and green brand at the company. The results of bibliometrics analysis on the selected theme confirmed the increasing numbers of papers which focused on analysing the relationships between the efficiency of environmental management and green brand at the company. In the paper, the authors used the VosViewer with the purpose to visualise the main scientific patterns on the selected theme. At the second stage, the authors identified the relationships between green brand and environmental management at the company using the ANOVA model. The data for analysis was obtained from the questionaries among companies management (which promote as green companies) and companies' financial statements. The two indicators described the green brand: loyalty to the green brand (frequency of searching company's brand in Google); net profit. The findings proved that companies with effective environmental management had a higher net profit and loyalty to the green brand.
Introduction to the cartographic and sedimentological study of the coverage of the TAHANAOUT BASIN (HIGH ATLAS, MOROCCO)
Authors: Abdelouhed Farah , Algouti Ahmed , Algouti Abdellah , EL konty Idir , Ezziyani Aboubakr
Published: February 2021

This study is carried out on the northern edge of the High Atlas of the MARRAKECH basin. The TAHNAOUT DOUAR SOUR basin belongs to the Atlasic domain which is structured by the Hercynian orogeny, taken up and elevated by the Alpine orogeny, our main goal in this studying is to map the TAHNAOUT DOUAR SOUR basin and to characterize all these geological formations, For this purpose we analysed sedimentary tectonic structures ,made lithostratigraphic sections with description and draw a geological map at scale 1/25000 on a topographic background by used MapInfo platform. As final results, our studying of the TAHANOUT basin consists of two main lithological units: the basement formed by conglomeratic and turbidite deposits (alternating sandstone and pelites), and the lithological unit that forms the cover of the TAHNAOUT basin formed by a red detrital material and, carbonate deposits in some cases depending on the deposition environment, The TAHNAOUT basin is also affected by tectonic activity at the basement and Meso-Cenozoic cover levels [1-2]. Magmatic activity is absent and no trace has been recorded.
The impact of experiential learning on Environmental Education during a Moroccan summer university
Authors: Bouhazzama Malak , Mssassi Said
Published: February 2021

In this study, the goal is to explore the impact of Experiential Learning Theory (ELT) and different experiential approaches on learning about sustainable development in environmental experiential learning education. Teachers were involved in participation with students to enhance their understanding of the importance of environment, developing their aptitude to combine theory and practice, also expanding their global vision. In order to accomplish this project with original learning opportunities, qualitative data of thirty participators was collected and revealed important issues in terms of pedagogical methodology in applying this theory. Overall, this paper shows the great capacity of learners to identify their styles and modes of learning and to expand them in all disciplines and fields even in their personal usual or professional life in the future and proposes global innovations in Moroccan environmental education.
Screening of essential oils activity against a gram negative psychrophilic bacterium isolated from aquatic environment (Water & Biofilm)
Authors: Kritihi Assia. , Ouaissa Khadija , Maychal Abdelaziz , Oumessaoud Younes , Hasnaoui Mustapha
Published: February 2021

Among the applications of medicinal plants, it is their use as antimicrobial agents. The objective of this study was to investigate the effect of some essential oils against an etiological pathogen Flavobacterium spp. responsible for several lost in rainbow trout, (Oncorhynchus mykiss) hatcheries, the strains used in this study were isolated from rearing tanks water and biofilm, identified as Flavobacterium spp. based on phenotypic, biochemical and enzymatic characterizations. A collection of eight essential oils were extracted, analyzed and tested for an inhibitory activity against the isolated strains, the effect on this bacterium has been demonstrated by the aromatogram method based on a screening of bacterial growth in a solid medium culture with disks containing essential oils. Our study’s results show that the chemical composition of the extracted essential oils play a crucial role in their antibacterial activity, which varies from 6 mm up to 34 mm as maximal inhibitory diameter.
Harmful micro-algal blooms and local environmental conditions of the coastal fringe: Moroccan Mediterranean coasts as a case study
Authors: Sitel Ferdaous , Rijalebled Belahcen , Er-Raioui Hassan
Published: February 2021

The dynamic study of harmful phytoplankton, conducted from June 2013 to May 2014, has tracked the evolution of the microalgae community at four sites located along the Moroccan western Mediterranean coast. 91 species and genera of phytoplankton were identified, 8 of which are recognized as potentially toxic. The genus Pseudo-nitzschia, a diatom known to produce domoic acid, is quite prevalent in all four sites, particularly in spring. The toxic dinoflagellate species detected in our study are Gymnodinium catenatum, Alexandrium sp PSP producers, Prorocentruml Lima, Dinophysis acuminata, D. caudata, D. fortii DSP producer, and Ostreopsis sp known palytoxin producer. The species Gymnodinium catenatum proliferates intensively from S1 to S3 in winter and S4 in summer, while Alexandrium sp proliferates mainly during spring and late summer with an exceedance of the threshold. Significant blooms of Dinophysis sp were recorded during the summer at all sites. On the other hand, the abundance of Ostreopsis sp was noted during the spring summer period with low concentrations. Discriminant analysis (DFA) of nutrients, toxic species identifies perfect seasonal discrimination. Winter and fall are characterized by high nutrient inputs, but algal biomass is low. On the contrary, spring and summer are characterized by a depletion of nutrients in the environment following the assimilation of these elements by phytoplankton.
Magnetic particles in the sediments of the south Ukraine rivers as the marker of the technogenic impact on the hydroecosystems
Authors: Alokhina Tetiana
Published: February 2021

Long-term and large-scale man-made activity in the mining areas affects to all components of the biosphere. The result of mining impact on hydroecosystems is addition to natural sources of sedimentary material technogenic components in large volumes. Magnetic particles are one of technogenic components which come with surface run-off to the river bed. We have studied the content of magnetic particles in the sediments of the south Ukraine rivers: the Inhulets River and the Inhul River ‒ the tributaries of the Dnieper and the Southern Buh, respectively. The Inhulets River flows along the Kryvyi Rih iron ore deposit, parallel the river there is a chain of open-pits, mines, mining and processing plants, a metallurgical plant. The results of our research were demonstrated within the Kryvyi Rih industrial agglomeration a number of magnetic particles in the sediment samples varies from 59,5% to 2,1%. Upstream from the Kryvyi Rih city on 10-15 km a number of magnetic particles is within 1,5%. Based on numerous sources of literature and own researches, it has been determined that detection of magnetic particles and properties is a convenient, cheap, quick and informative method of technogenic pollution studying of river sediments and also mirror the industrial history of the region.
Development of a software for the control and the supervision of the climatic parameters under greenhouse
Authors: Didi Samir , El hassini Abdelkrim
Published: February 2021

To meet the climatic needs of plants, there is a growing interest in the development of methods to automatically and continuously detect the constraints on plants, and to use water and nutrients under greenhouse crops in a rational way. The objective of this work is consecrated to the development of a software for the control and supervision of climatic parameters under greenhouses by an automatic process using LabVIEW. The system carried out makes it possible to measure the various values of the physical sizes resulting from various sensors (temperature, humidity, illumination, content of CO2, moisture of the ground,…). In order to visualize in real time, the evolution of the various climatic parameters, a graphic interface of supervision was developed by using the programming language LabVIEW. The latter makes it possible to integrate functions of control such as the modification of the instructions and the control commands to maintain the conditions adapted to the culture under greenhouse. The installation of such a strategy must take account of the economy of the water resources, nutritive elements and electric power while making it possible to the farmers to increase their productions as well in quantity and in quality.
Blockchain-based medical and water waste management conception
Authors: Kassou M , Bourekkadi S , Khoulji S , Slimani K , Chikri H , Kerkeb M.L.
Published: February 2021

The revolutionary technology blockchain began with cryptocurrencies like bitcoin but has since expanded beyond the worlds of finance and banking. One relatively unexplored application domain is medical and water waste. The production of medical/water waste is an integral part of healthcare operations. However, Health care and water waste management methods can also pose a health and environment risk if the various steps in the management process are not carried out correctly. The objective of this paper is to propose conception of a system, based on the Blockchain and IoT, that ensures the control of these wastes in order to effectively manage, coordinate and monitor their disposal. An initial design of this system and an evaluation of the system's performance are also presented.
Micro-mechanical (granular) mixtures for environmental safety technologies
Authors: Gerasymov Oleg , Spivak Andrii , Andrianova Iryna , Sidletska Liudmyla , Kuryatnikov Vladyslav , Kilian Andrii
Published: February 2021

One of the most significant problems that belong to effective use of granular materials GM (for example, in the construction, pharmacological, chemical, agricultural and some other industries, as well as in the technologies of screening against internal radiation) is the difficulty of ensuring their maximum compaction in order to increase the efficiency of their practical application. In this way, we study of the properties of binary granular systems, the dynamics of their compaction and the impact on this process of the ratio of component sizes and partial parameters in order to provide an innovative step in the development of appropriate technologies. To this end, we propose to use the apparatus of Kirkwood-Buff theory in combination with model equations of state, like Carnahan-Starling, together with relevant phenomenological information, which obtained from direct observations. We report theoretically the fundamental possibility of increasing the degree and speed of packaging and at first describe substantiate empirical data in the full range of values of the volume (or molar) fraction.
Water hydrochemistry of Lake Boudaroua in the Moroccan Prerifwest Mediterranean region
Authors: En-nkhili Hicham , Etebaai Issam , El kharrim Khadija , Belghyti Driss
Published: February 2021

In order to assess the quality of surface water of Boudaroua Lake, located in the Moroccan Pre-rif.The water quality parameters was used to evaluate the potential presence of toxicity of this ecosystem. To this end, samples and hydrochemical analyzes were carried out for five permanent stations around the Lake, during the study period (July 2019, October 2019, January 2020). The study was based on 11 parameters, namely, turbidity (TUR), dissolved oxygen (O2), total hardness (DT), calcium (Ca2+),magnesium(Mg2+), sodium (Na+),potassium (K+), ammonium (NH+4), chloride(Cl−), sulfate( SO2−4), nitrate (NO-3)were considered. The results obtained of these physicochemical parameters have been compared with the Moroccan standard (MS) for surface water and with the World Health Organization (WHO). The results indicated that the values of the physicochemical parameters varies significantly seasonally due to precipitation rate variation. In addition the impact of Agricultural pollution resulting from the excessive use of fertilizers that enter the lake through waterways, such as ammonium NH+4, and dissolved oxygen (O2) its value reaching respectively 1.09 mg/L ,12 mg/L remains above standards (MS) and (WHO) which could harm the ecosystem of the lake.
FEM simulation of bending and torsion tests of similar size RHS but of the different production options
Authors: Kukhar Volodymyr , Sahirov Yurii , Hornostai Vadym , Markov Oleg , Nahnibeda Mykyta
Published: February 2021

The paper implements a method for analyzing the stress-strain state of rectangular hollow sections (RHS) by finite-element modeling (FEM) of tests for three-point bending and torsion. Design schemes, 3-D solid-state and deformable models have been developed using the automated analysis and CAD/CAE system software, made it possible to obtain equivalent stress distributions and displacements in models. A simulation of tests for RHS with a cross section of 40 mm × 50 mm, manufactured in two ways, was carried out: (a) by direct-forming of galvanized steel strips on roll-forming mill in a semi-closed section with a longitudinal gap of 0.5 mm between the edges formed on a 40 mm web (DF-RHS); (b) similar direct-forming to the closed section and next welding the edges to a longitudinal weld along the web middle of 50 mm (DFW-RHS). RHS with various wall thicknesses (t = 1.93 mm, 1.84 mm and 0.7 mm) was investigated, given the design features that depend on the manufacturing processes of structural sections. It was found DFW-RHS is stiffer by at least 50% compared to DF-RHS, which allows to savings the metal by reducing the RHS wall thickness by 62% while maintaining the same stiffness and ensuring high strength of structural section.
Experimental design and modeling of removal of organic matter and nutrients in the OMW by calcium bentonite
Authors: Ait Hmeid Hanane , Akodad Mustapha , Baghour Mourad , Moumen Abdelmajid , Skalli Ali , Azizi Ghizlane
Published: February 2021

The present work reports the application to reduction of the organic matter and nutrients in oil mill liquid waste (OMW), using the natural calcium bentonite from Morocco as adsorbent. The margine is characterized by a high concentration of low biodegradable and highly toxic organic matter. In order to evaluated the reduction capacity of bentonite to remove organic matter and nutrients, characterization mineralogical, chemical and also morphological of adsorbent were conducted. During the experiment and in the scenarios studied, all the total of parameters adsorbed was strongly depend on the percentage of bentonite. While, the percentage of pH of OMW was gradually decreased from 4.03 to 8. 04. The COD concentrations were decreased from 172.72 to 29.71 g/l, and also the phosphorus concentrations were decreased from 1.16 to 0.29 g/l. The electrical conductivity decrease in this work from 16.93 to 0.17 mS/cm. This present work proves that calcium bentonite is an effective adsorbent for the elimination the nutrients and organic compound.
Geothermal potential mapping of Northeast Morocco (Bekrane-Ahfir) using remote sensing data and GIS
Authors: Morabit Intissar El , Maimouni Soufiane , Fekri Ahmed
Published: February 2021

Geothermal energy is part of the renewable energy mix. It is used for heating, air conditioning and sometimes even for the production of electricity. Prospecting for such a resource proves to be a difficult and capital-intensive task. To overcome this constraint, we have used remote sensing which is an adequate tool to guide the prospecting through the elaboration of hydrothermal resource potential maps at the level of zones that present a favorable potential for exploitation (hyper-tectonized sites, volcanic sites, faulted sites, sites with hot geological formations, seismic zones...). The objective of this work is to carry out a study on the North-East of Morocco (Berkane Province), in order to identify favorable sites for geothermal exploitation such as geologically and hydrogeologically active sites. The methodology adopted consists in processing the images of the OLI (Operational Land Imager) and TIRS (Thermal Infrared Sensor) sensors of the Landsat-8 satellite in order to extract spectral indices (Clay mineral Index and Ferrous mineral Index,) detecting a geothermal activity and the surface temperature map (LST) using muticriteria analysis method (MCA). ) in the north-eastern part of Morocco. The results obtained show an almost perfect concordance of the distribution of the above-mentioned indices, with the map of lineaments which are considered as heat drains from the depth to the surface. Moreover, a correct correlation was established during the validation of these results with the map of the inventory of hydrothermal springs identified in the study area.
Metaheuristics methods for The VRP in Home Health Care by minimizing fuel consumption for environmental gain
Authors: Ettazi Haitam , Rafalia Najat , Abouchabaka Jaafar
Published: February 2021

Nowadays, the international society began to see clearly the impact of neglecting the environmental aspect in our lives, especially the issue of global warming. This paper aims in the first degree to minimize the carbon emission by vehicles and in doing so help to reduce the pollution ratio that is increasing day by day. In the home care sector, a patient requires from a health structure offering home care services one or many services to be done at home. For this purpose a health staff is mobilized to provide these services and must be done optimally. Many papers dealing with this kind of problems are suggesting that the way to optimize the problem encountered efficiently is to use the resources put in place to minimize the total travelled distance, but in this perspective, the study prioritizes the reduction and minimizing the fuel consumption. To answer all this questions, an exploration and an investigation of the problems addressed in the literature is performed, after that a mathematical formulation of the problem and two metaheuristics methods are proposed to resolve this problem. In the end, a comparison of the results of the two methods is presented.
Explaining the Atlas Cedar (Cedrus atlantica M.) dieback by studying Water relations of young plants subject to an edaphic drought
Authors: Taoufik Aadel , Atmane Rochdi , Abdenbi Zine El Abidine
Published: February 2021

Cedrus atlantica M. stands from the Middle Atlas Mountains in Morocco have been severely affected by dieback. The edaphic water deficit could be the cause that triggered this phenomenon leading to the mortality of dying trees. The objective of this work is to analyze the ecophysiological behavior of Atlas cedar seedlings subjected to an edaphic drought of progressive intensity. During the drying cycle, the relative moisture content of the substrate decreased significantly to reach 12.71% at the end of the test; 4.27% and 2.88% respectively for the basaltic, calcareous, and sandy substrate. The pre-dawn water potential reached very low values of -32.25, -37.38, and -39.50 bar at the end of the water drying cycle. The critical water potential varied between -36 and -39 bar depending on the type of substrate. The mean maximum stomatal conductance under favorable water conditions was of the order of 330 mmol/m2/s. It was reduced, due to drying, in proportion to the reduction in substrate moisture content. Atlas cedar maintains gas exchange under conditions of severe water stress but can be lethal with extreme and recurrent droughts. This behavior can explain the development of the phenomenon of cedar stand decline, which is more accentuated especially with adverse ecological conditions.
Research on the Influence of Leadership Style on Employee Innovation Behavior in Agricultural Science and Technology enterprises
Authors: Fu Na , Zhang Tongyue , Nie Xiaodan , Li Min
Published: February 2021

Innovation is the key factor to promote agricultural modernization. Employees are the implementers of innovation, and the managers, as the leaders of enterprises, have an important impact on employees’ innovation behavior. This paper takes agricultural science and technology enterprises as the research object, studies the influence of different leadership styles on employees’ innovation behavior, and proposes suggestions to improve the leadership style to promote employees’ innovation behavior, so as to improve the innovation ability of agricultural science and technology enterprises.
Research on economic development strategy based on big data
Authors: Shen Tuofu
Published: February 2021

Since the 21st century, data has grown exponentially, and the world has entered the era of big data. In the era of big data, the core assumptions and research methods of economics have changed, and data-driven development paradigm has gradually become the main development paradigm of economics. From the perspective of economics and economics, this paper expounds the impact of economics, economics and Economics on the development of data driven models. The research in this paper is conducive to in-depth understanding of the development and changes of economics in the era of big data, and can promote the public to better participate in economic activities and understand the operation of market economy in the information age.
Fast response acetone-sensing properties of SnO2 nanoparticles prepared by the sol-gel method
Authors: Wang Jiaxing , Yu Hai , Zhang Yong
Published: February 2021

SnO2 nanoparticle architectures were successfully synthesized using a sol-gel method and developed for acetone gas detection. The morphology and structure of the particles were characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM). The SnO2 nanoparticle architectures were configured as high-performance sensors to detect acetone and showed a very fast response time (<1 s), a short recovery time (10 s), good repeatability and high selectivity at a relatively low working temperature. Thus, SnO2 nanoparticles should be promising candidates for designing and fabricating acetone gas sensors with good gas sensing performance. The possible gas sensing mechanism is also presented.
Exploring Tractive Performance of Planetary Rover's Rigid Wheels on Mixed Terrain
Authors: Zhai Guanglong , Huang Tieqiu
Published: February 2021

Based on insufficient studies of the tractive performance of a planetary rover's rigid wheels in soft soil and hard mixed soil terrains, a method for studying the tractive performance is presented. The Wong-Reece' interaction model was used as the dynamic model for wheel-soil contact. The sinkage model and the drawbar pull force model were modified and then verified with experimental results. Based on the Hertz contact theory, a nonlinear friction spring damping model was adopted as the wheel-bedrock contact model. An additional terrain hardness array was introduced for setting and recognizing the mixed terrain with ground mechanics parameters. With the platform for co-simulating the navigation and dynamics of a planetary rover, the simulation program was developed to dynamically simulate the whole planetary rover with two wheel-ground contact models. Taking the Mars rover as an example, its whole model was established with the MSC.Adams software. The dynamic simulation of the Mars rover on the soft terrain and mixed terrain was carried out respectively. The simulation results show that the Mars rover's velocity fluctuates greatly on the mixed terrain, and that the Mars rover gains greater drawbar pull force when traveling on the mixed terrain than on the only soil terrain.
A New SLAM Algorithm with Key-Frame Estimation and Local Map Upgrade Scheme
Authors: Zhang Zhao , Zhang Yi , Huang Rui
Published: February 2021

Simultaneous Localization and Mapping(SLAM) is the most important tool in creating map and auto-navigation, which is an indispensable link for pilotless automobile. The current SLAM algorithms suffer from unreliable feature matching and large registration error. To reduce those deficiencies, we proposed a key-frame estimation and local map upgrade scheme, which include the following 3 parts:1) Local map matching strategy; 2) Local map updating scheme; 3) Key-frame selecting scheme. Experimental results proved that our scheme improved the performance of current localization methods.
Geburtsassoziierte vaginale Fisteln und weibliche Genitalverstümmelung
Authors: Spindler Rahel , Maleki Faranak , Rieke Burkhard
Published: February 2021

Peripartal entstandene vesikovaginale oder rektovaginale Fisteln – kurz Geburtsfisteln – sind in Deutschland eine Rarität und eher von medizinhistorischer denn von klinischer Bedeutung. Dementsprechend gering ist unser Wissen über das Krankheitsbild als solches und die zugrunde liegenden Risikofaktoren. Im sogenannten Fistelgürtel Subsahara-Afrikas treten Geburtsfisteln jedoch nach wie vor häufig auf und haben weitreichende medizinische und soziale Folgen für die betroffenen Frauen. Gleichzeitig ist in vielen dieser Länder auch die Praxis der weiblichen Genitalverstümmelung weit verbreitet. Im Rahmen einer ärztlichen Fortbildungsreise nach Äthiopien stellte sich unserer Reisegruppe die Frage, inwieweit es zwischen diesen beiden großen Bürden der Frauengesundheit in den ärmsten Ländern der Welt einen kausalen Zusammenhang gibt.
Intravesikale Gemcitabin-Instillationstherapie bei BCG-Versagen und Mitomycin-Allergie – Der besondere Fall einer Patientin mit invertiertem Papillom der Harnblase
Authors: Matzen Merle , Offermann Anne , Tharun Lars , Perner Sven , Merseburger Axel S. , Kramer Mario , Hupe Marie Christine
Published: February 2021

Die Instillationstherapie stellt im Feld der urothelialen Neoplasien der Harnblase eine einzigartige Therapiemöglichkeit dar, die so in keinem anderen medizinischen Bereich zur Anwendung kommt. Mit der Wahl des zu instillierenden Medikamentes hat sich die Forschung der vergangenen Jahre intensiv beschäftigt, hierbei hat sich besonders der Einsatz von Bacillus Calmette-Guerin (BCG) und Mitomycin C (MMC) bewährt. Weitere Medikamente, die jedoch seltener zum Einsatz kommen, sind Chemotherapeutika wie Gemcitabin, dessen klinische Relevanz in diesem Artikel beleuchtet werden soll.

So vielfältig, wie die Therapiemöglichkeiten der Harnblasentumore, ist auch ihre Histopathologie. Das invertierte Papillom stellt im Formenkreis der urologischen Erkrankungen eine seltene Krankheitsentität dar. Eine Assoziation zum nicht-muskelinvasiven Harnblasenkarzinom wird diskutiert.

Wir berichten von dem Fall einer Patientin mit invertiertem Papillom der Harnblase, welche nach Versagen einer BCG-Therapie und einer allergischen Reaktion gegen MMC mit einer Gemcitabin-Instillationstherapie behandelt wurde.
Rassismus in der Medizin
Authors: Girth Ernst
Published: February 2021

„Rassismus existiert auch im Gesundheitswesen“ –Ein Gespräch mit demMenschenrechtsundRassismusbeauftragten der Landesärztekammer Hessen Dr. Ernst Girth
Adenoma detection by Endocuff-assisted versus standard colonoscopy in an organized screening program: the “ItaVision” randomized controlled trial
Authors: Zorzi Manuel , Hassan Cesare , Battagello Jessica , Antonelli Giulio , Pantalena Maurizio , Bulighin Gianmarco , Alicante Saverio , Meggiato Tamara , Rosa-Rizzotto Erik , Iacopini Federico , Luigiano Carmelo , Monica Fabio , Arrigoni Arrigo , Germanà Bastianello , Valiante Flavio , Mallardi Beatrice , Senore Carlo , Grazzini Grazia , Mantellini Paola ,   and the ItaVision Working Group
Published: February 2021

Background The Endocuff Vision device (Arc Medical Design Ltd., Leeds, UK) has been shown to increase mucosal exposure, and consequently adenoma detection rate (ADR), during colonoscopy. This nationwide multicenter study assessed possible benefits and harms of using Endocuff Vision in a fecal immunochemical test (FIT)-based screening program.

Methods Patients undergoing colonoscopy after a FIT-positive test were randomized 1:1 to undergo Endocuff-assisted colonoscopy or standard colonoscopy, stratified by sex, age, and screening history. Primary outcome was ADR. Secondary outcomes were ADR stratified by endoscopists’ ADR, advanced ADR (AADR), adenomas per colonoscopy (APC), withdrawal time, and adverse events.

Results 1866 patients were enrolled across 13 centers. After exclusions, 1813 (mean age 60.1 years; male 53.8 %) were randomized (908 Endocuff Vision, 905 standard colonoscopy). ADR was significantly higher in the Endocuff Vision arm (47.8 % vs. 40.8 %; relative risk [RR] 1.17, 95 % confidence interval [CI] 1.06–1.30), with no differences between arms regarding size or morphology. When stratifying for endoscopists’ ADR, only low detectors (ADR < 33.3 %) showed a statistically significant ADR increase (Endocuff Vision 41.1 % [95 %CI 35.7–46.7] vs. standard colonoscopy 26.0 % [95 %CI 21.3–31.4]). AADR (24.8 % vs. 20.5 %, RR 1.21, 95 %CI 1.02–1.43) and APC (0.94 vs. 0.77; P  = 0.001) were higher in the Endocuff Vision arm. Withdrawal time and adverse events were similar between arms.

Conclusion Endocuff Vision increased ADR in a FIT-based screening program by improving examination of the whole colonic mucosa. Utility was highest among endoscopists with a low ADR.
Development of a Continuous Photochemical Benzyne-Forming Process
Authors: Baumann Marcus , Bracken Cormac , Batsanov Andrei S.
Published: February 2021

A continuous-flow process is presented that enables the safe generation and derivatization of benzyne under photochemical conditions. This is facilitated by a new high-power LED lamp emitting light at 365 nm. The resulting flow process effectively controls the release of gaseous by-products based on an adjustable backpressure regulator and delivers a series of heterocyclic products in a short residence time of 3 minutes. The robustness of this methodology is demonstrated for the rapid generation of benzotriazoles, 2H-indazoles and various furan-derived adducts, facilitating the preparation of these important heterocyclic scaffolds via a simple and readily scalable flow protocol.
4-Cyano-3-oxotetrahydrothiophene (c-THT): An Ideal Acrylonitrile Anion Equivalent
Authors: Arseniyadis Stellios , Richard François , Mateos Carlos
Published: February 2021

4-Cyano-3-oxotetrahydrothiophene (c-THT) has much more to offer than just a platform to various heterocyclic scaffolds. This solid, bench-stable and commercially available reagent can be readily transformed into thioglycolic acid and acrylonitrile upon simple addition of a hydroxide anion. This interesting feature enables its use as a particularly versatile acrylonitrile anion surrogate.
Incidental Gallbladder Cancer: Routine versus Selective Histological Examination After Cholecystectomy
Authors: Alabi Andrew , Arvind A D. , Pawa Nikhil , Karim Shakir , Smith Jason
Published: February 2021

Background Incidental gallbladder cancer is relatively rare, with an incidence ranging between 0.19 and 5.5% of all the cholecystectomies for benign disease, and carries a poor prognosis. Currently, in the literature, there appears to be some controversy about whether all gallbladder specimens should be sent for routine histopathology. The aim of this study was to investigate the need for either routine or selective histopathological evaluation of all gallbladder specimens following cholecystectomy in our institution.

Methods The records of all patients who underwent a cholecystectomy (laparoscopic and open) for gallstone disease over a 5-year period (between January 2011 and January 2016) were reviewed retrospectively in a single university teaching hospital. Patients with radiological evidence of gallbladder cancer preoperatively were excluded. The notes of patients with incidental gallbladder cancer were reviewed and data were collected for clinical presentation and preoperative investigations including blood tests and radiological imaging.

Results A total of 1,473 specimens were sent for histopathological evaluation, with two patients being diagnosed with an incidental gallbladder cancer (papillary adenocarcinoma in situ and moderately differentiated invasive adenocarcinoma [stage IIIa]). The incidence rate was 0.14%. All patients with incidental gallbladder cancer had macroscopically abnormal specimens.

Conclusion Both patients in our study who were diagnosed with incidental gallbladder cancer had macroscopic abnormalities. A selective rather than routine approach to histological evaluation of gallbladder specimens especially in those with macroscopic abnormalities should be employed. This will reduce the burden on the pathology department with potential cost savings.
Teleconsultation and Teletreatment Protocol to Diagnose and Manage Patients with Benign Paroxysmal Positional Vertigo (BPPV) during the COVID-19 Pandemic
Authors: Barreto Renato Gonzaga , Yacovino Darío Andrés , Teixeira Lázaro Juliano , Freitas Mayanna Machado
Published: February 2021

Introduction Telehealth consists in the application of technology to provide remote health service. This resource is considered safe and effective and has attracted an exponential interest in the context of the COVID pandemic. Expanded to dizzy patients, it would be able to provide diagnosis and treatment, minimizing the risk of disease transmission. Benign paroxysmal positional vertigo (BPPV) is the most common vestibular disorder. The diagnosis typically rests on the description of the symptoms along with the nystagmus observed at a well-established positional testing.

Objectives The aim of the present study was to propose a teleconsultation and teletreatment protocol to manage patients with BPPV during the COVID-19 pandemic.

Methods Specialists in the vestibular field met through remote access technologies to discuss the best strategy to manage BPPV patients by teleconsultation and teletreatment system. Additionally, several scientific sources were consulted. Technical issues, patient safety, and clinical assessment were independently analyzed. All relevant information was considered in order to design a clinical protocol to manage BPPV patients in the pandemic context.

Results Teleconsultation for BPPV patients requires a double way (video and audio) digital system. An adapted informed consent to follow good clinical practice statements must be considered. The time, trigger and target eye bedside examination (TiTRaTe) protocol has proven to be a valuable first approach. The bow and lean test is the most rational screening maneuver for patients with suspected positional vertigo, followed by most specific maneuvers to diagnostic the sub-variants of BPPV.

Conclusion Although with limited evidence, teleconsultation and teletreatment are both reasonable and feasible strategies for the management of patients with BPPV in adverse situations for face-to-face consultation.
Pediatric Fronto-Orbital Skull Reconstruction
Authors: Ferry Andrew M. , Dibbs Rami P. , Sarrami Shayan M. , Abu-Ghname Amjed , Beh Han Zhuang , Maricevich Renata S. , Buchanan Edward P.
Published: February 2021

Craniofacial surgery in children is a highly challenging discipline that requires extensive knowledge of craniofacial anatomy and pathology. Insults to the fronto-orbital skeleton have the potential to inflict significant morbidity and even mortality in patients due to its proximity to the central nervous system. In addition, significant aesthetic and ophthalmologic disturbances frequently accompany these insults. Craniosynostosis, facial trauma, and craniofacial tumors are all pathologies that frequently affect the fronto-orbital region of the craniofacial skeleton in children. While the mechanisms of these pathologies vary greatly, the underlying principles of reconstruction remain the same. Despite the limited data in certain areas of fronto-orbital reconstruction in children, significant innovations have greatly improved its safety and efficacy. It is imperative that further investigations of fronto-orbital reconstruction are undertaken so that craniofacial surgeons may provide optimal care for these patients.
The carbon state in dilute germanium carbides
Authors: Gulyas Istvan A. , Stephenson Chad A. , Meng Qian , Bank Seth R. , Wistey Mark A.
Published: February 2021

Conduction and valence band states for the highly mismatched alloy (HMA) Ge:C are projected onto Ge crystal states, Ge vacancy states, and Ge/C atomic orbitals, revealing that substitutional carbon not only creates a direct bandgap but also the new conduction band is optically active. Overlap integrals of the new Ge:C conduction band state with states from unperturbed Ge show that the new band cannot be attributed to any single Ge band but is a mixture of multiple Ge states. The Ge Γ conduction band valley state plays the largest single role, but L and X valley states collectively contribute a larger share than Γ due to the multiplicity of degenerate states. C sites structurally resemble uncharged vacancies in the Ge lattice, similar to Hjalmarson's model for other HMAs. C also perturbs the entire Ge band structure even at the deepest crystal core energy levels, particularly if staggered supercells are used to mimic a disordered alloy. Projection onto atomic sites shows a relatively weak localization compared with other HMAs, but it does show a strong anisotropy in probability distribution. L-valley conduction band states in Ge contribute to the conduction band minimum in Ge:C, but the optical transition strength in Ge:C remains within a factor of 2 of the direct gap transition in Ge.
Simulation of pulsed electron-beam emission from a triggered multi-gap pseudospark device
Authors: Zhang Jia , Ji Xin , Cheng Qi , Jia Jing
Published: February 2021

Results simulating time-resolved pulsed electron-beam emission from a triggered four-gap pseudospark device are presented. It is important for many applications to explore the mechanisms of the pulsed electron-beam current generated in the multi-gap pseudospark discharge devices. From experiments, it is known that the pulsed emitted electron pulse is principally at the beginning, characterized by a rather short part of high energetic electrons followed by a broad pulse of electrons with an average energy of half of applied voltage. These characteristics of the electron-beam current have been simulated for a four-gap pseudospark discharge device with anode voltages from 20 to 50 kV, and with Ar as working gas in a pressure range from 20 to 60 Pa. According to the results, when the pressure becomes higher than a specific threshold, the two peaks are found to merge together. When the anode voltage is 20 kV, the pressure threshold is about 30 Pa. When the anode voltage is above 30 kV, the pressure threshold is about 40 Pa. It is observed that the energy spectrum of the high-energetic part of pulsed electron-beam contains a large peak corresponding to several keVs in the initial stage, and then it shifts toward lower energies. From the simulation, this specific characteristic is verified that the time duration of the high-energetic part of the pulsed electron-beam current grows with increasing anode voltage and decreasing pressure.
Research on the effect of air flow extinguishing arc in double jet non-equilibrium field
Authors: Wang Jufeng , Zhang Qixing , Li Zijian , Xu Yuheng , Huang Shangshi , Huang Ping
Published: February 2021

A dual-jet arc-extinguishing method is proposed in order to improve the performance of jet-extinguishing gaps for extinguishing large currents and reducing the lightning trip-out rate of power lines. Meanwhile, we studied the arc-extinguishing effect of the dual-jet non-equilibrium field gas flow. Based on this, a Double Jet Arc Extinguishing Gap (DJAEG) is developed. First of all, the jet field arc extinction modeling analysis is carried out by coupling the typical MAYR arc model with the jet field. Then, the COMSOL MUTIPHSICS simulation software is used to simulate the arc extinction of the DJAEG in the balanced flow field and the non-balanced flow field. Finally, the DJAEG extinguishment arc test is carried out through the construction of the power frequency continuous flow interruption test. The simulation results show that the velocity of the high-speed jet emitted by the DJAEG can reach 3000 m/s, and the arc can be extinguished within 4 ms. These results also verified that the dual jet non-equilibrium flow field has the characteristics of long jet sustaining time. The test results show that the DJAEG successfully extinguished the arc within 4 ms, and there was no reignition. This means that the dual-jet non-equilibrium field has an obvious arc extinction effect.
Analysis and design of a self-oscillating quasi-digital fluxgate current sensor for DC current measurement
Authors: Yang Xiaoguang , Chen Meiqi , Jia Zhe
Published: February 2021

In this paper, an open-loop self-oscillating fluxgate-based current measurement method is presented. The proposed sensor does not require the low-pass filter necessary in traditional measurement technologies and does not require an analog-to-digital converter when connected to digital systems. More importantly, although the proposed measurement method is based on the open-loop configuration, its measurement accuracy is close to that of the traditional self-oscillating fluxgate measurement technology based on the closed-loop configuration. Accurate mathematical models are established to describe the basic characteristics of the measurement method, and design criteria of the sensor are proposed. The test results show that the proposed measurement method has good linearity; for example, in the full scale of 100 A, its linearity is about 0.4% and can be improved to below 0.2% when the first-order polynomial fitting method is used.