bluuebunny/crossref_metadata_2025 huggingface dataset:
Alternative pavement heating technique using renewable energy in North Dakota
Authors: Ho I-Hsuan , Li Sheng , Ma Li
Published: November 2020

Hydronic heating pavement (HHP) is considered to be more sustainable and environmental-friendly for de-icing or pavement heating. The more efficient approach is to use deep direct-use geothermal energy due to the high temperature and clean. In western North Dakota, several aquifers have been identified to provide geothermal hot water ranging from 34°C to 140°C within 2300 m below the ground surface. The current technique has made it feasible to utilize the hot water for power generation. Besides drilling new wells, the higher temperature water exits from power plant still has up to 70ºC. This temperature enables the valuable applications to cascading use for other purposes such as space heating, snow-melting for transportation infrastructure etc. This paper mainly focuses on studying the challenges of an HHP using geothermal water. Parametric studies using finite element analysis were conducted. Considering the high heat demands in western North Dakota due to the extreme weather, the suitable water temperatures, pipes layouts, mechanical properties of piped pavement, volumetric flow rates and thermal conductivity of pavement were analysed. The optimization of the HHP subject to different weather conditions and new findings are summarized and discussed.
Effect of anthropogenic heat sources in the shallow subsurface at city-scale
Authors: Kreitmair Monika J. , Makasis Nikolas , Bidarmaghz Asal , Terrington Ricky L. , Farr Gareth J. , Scheidegger Johanna M. , Choudhary Ruchi
Published: November 2020

Rapid rates of urbanisation are placing growing demands on cities for accommodation and transportation, with increasing numbers of basements and tunnel networks being built to meet these rising demands. Such subsurface structures constitute continuous heat sources and sinks, particularly if maintained at comfortable temperatures. At the city-scale, there is limited understanding of the effect of heat exchange of underground infrastructures with their environments, in part due to limited availability of long-term underground temperature data. The effects of underground temperature changes due anthropogenic heat fluxes can be significant, impacting ventilation and cooling costs of underground spaces, efficiency of geo-energy systems, quality and quantity of groundwater flow, and the health and maintenance of underground structures. In this paper we explore the impact of anthropogenic subsurface structures on the thermal climate of the shallow subsurface by developing a heat transfer model of the city of Cardiff, UK, utilising a recently developed semi-3D modelling approach.
In situ characterization of temperature and gas production using membrane interface probe (MIP) and hydraulic profiling tool (HPT) in an operating municipal solid waste landfill
Authors: Mousavi M. Sina , Feng Yuan , Afzalian Mostafa , McCann Josh , Eun Jongwan
Published: November 2020

A modern Municipal Solid Waste (MSW) landfill is a renewable energy resource to produce a significant amount of heat and methane used for generating electricity. However, it is difficult to use those sources effectively because active and post-closure MSW landfills are heterogeneous spatially and temporally and exposed to complex environments with varying pressure and moisture in the landfill. With regard to the prediction of the sources, the analysis of in situ MSW properties is an alternative way to reduce the uncertainty and to understand complex processes undergoing in the landfill effectively. A Hydraulic Profiling Tool (HPT) and Membrane Interface Probe (MIP) measures the continuous profile of MSW properties with depth, including hydraulic pressure, temperature, hydraulic conductivity, electrical conductivity (EC), and concentration of selected volatile organic compounds and methane. In this study, we conducted a series of MIP with HPT tests to investigate the MSW characteristics of a landfill in Nebraska. The results of the test showed an increase in hydraulic pressure and temperature with depth. The EC profile showed a variety of different waste constituents and MIP results showed the methane trapped beneath the top cover. The results in terms of hydraulic properties, temperature and EC obtained from different sites can be used to estimate the waste age and help designing energy recovery systems.
Comparison of 1-D seismic site response analysis tools for layered liquefiable deposits at an offshore windfarm site
Authors: Yu Hao , Ntambakwa Eric , Mendes Bruno
Published: November 2020

Various offshore wind farms have been proposed in the Taiwan strait with a long-term target of installing 4.2 gigawatts by 2030. The proposed projects will be in areas with various known faults and areal seismic sources which should be accounted for in design. A reliable prediction of site response for soil deposits is crucial for seismic loading evaluation of existing energy structures and for design of new structures including offshore wind farms in seismically active regions. This paper presents generic results of 1-D site response analyses based on work performed for an offshore wind power plant development site in the Taiwan strait. The deposits in the project area generally consist of layered deposits with liquefiable layers. The site response analyses were initially performed using two different open-source tools, DEEPSOIL and Cyclic 1D. Both equivalent linear and non-linear approaches were adopted for the analyses and additional evaluations were subsequently performed using PLAXIS 2D for comparison with the results from the open source tools. The results from the different tools were systematically compared and provided useful insight on peak ground (seabed) acceleration, acceleration time histories and shear strains at specific depths and design response spectra. The paper includes a discussion of the sensitivity of the outputs to various input parameters for each of the tools utilized in the analyses and the suitability and limitations of each approach for assessing liquefaction potential are also discussed.
Application of polymer thermal store material in fixed honeycomb regenerative heat exchanger
Authors: Penev Angel , Tsokov Lyubomir
Published: November 2020

The article considers the possibility to use different types of polymer thermal store materials for regenerative heat exchangers in local ventilation systems. The research provides evidence for the benefits of the replacement of the most commonly used metal and non-metallic materials in the manufacture of the regenerator honeycomb matrix. It does so by presenting the results of calculations and comparative analysis of the influence of thermo-physical properties of a wide range of polymers on the thermal efficiency of a fixed counter-flow regenerator operating with humid air. In order to evaluate the efficiency, we have used a numerical solution of the system of mathematical physics equations describing the process in the regenerator. The system also includes an appropriate CFD model of the evaporation-condensation phase change process.
Methodology for determination of heat losses from infiltration and ventilation and heat gains from people in overall energy balance of the building
Authors: Brazhanova Dana , Stoyak Vyacheslav , Ibragimova Madina , Terziev Angel
Published: November 2020

This paper proposes a new methodology of determining the building heat losses associated with natural and (or) forced air ventilation, based on continuous measurements of the temperature, humidity and carbon dioxide concentration in the air. Determining the flow rate of infiltrating air is performed by the active and passive experimental methods. The proposed method allows determining the exact amount of heat losses associated with ventilation or infiltration of the building under environmental conditions. In addition, the paper proposes an algorithm of calculating the actual number of people present in the room and the associated heat gains based on the air composition analysis. The proposed methods can be used as tools for conducting energy inspections of buildings and structures, as well as be part of effective building energy supply management systems.
An option for integration of Carnot Battery into a small Nuclear Power Plant
Authors: Borissova Ana , Popov Dimityr
Published: November 2020

This article proposes a combination of nuclear power plant and grid-scale energy storage, classified as Carnot battery. The electric heater heats molten salts when excess electricity is available in the grid. The steam that is produced in a small modular nuclear reactor is heated with hot molten salts in the external super-heater. For continuous superheating to be ensured, the plant is equipped with molten salt thermal energy storage. The combined plant and reference NPP are modelled and simulated at steady-state conditions. Due to the higher turbine inlet temperature, the efficiency of the combined generation-storage nuclear plant is substantially improved. The proposed concept makes the co-location of NPP and Carnot Battery more attractive than the separate plants. The integrated thermal storage acts as secondary electricity storage. As such, it surpasses compressed air storage and is competitive with the pumped hydro storage, in the absence of their geographical and environmental constraints.
Model research of the energy efficiency of a cogeneration backpressure steam turbine installation
Authors: Genovski Ivan , Hristov Kaloyan
Published: November 2020

In the contemporary district heating systems (DHS) heat energy for the customers is generated by cogeneration method, which leads to the saving of primary energy resources compared to the separate production method. The most widespread technology for combined production is based on steam turbine installations with adjustable steam extraction and backpressure steam turbine. In these technologies district heating water is heated to the required temperature either in district heaters in case of steam turbine with adjustable steam extractions or in boiler-condenser in case of backpressure steam turbine installations. The temperature of the district heat water at the inlet of the CHP installation depends on the mode of operation of the DHS. The heat load, distributed to consumers, is regulated at the heat source (CHP installation) by temperature and flow rate of the district heating water, mainly following the change in climatic factors. Current study presents the development of a simulation model of existing CHP backpressure steam turbine. The object studied is a backpressure steam turbine type SST-300 CE2L/V36S. Presented are results from the validation of the simulated model with data from the design documentation. The model has been used to study the energy efficiency of a steam turbine installation based on multivariate simulation calculations. The results obtained relate the energy efficiency indicators of CHP backpressure steam turbine with the factors that characterize the mode of operation of the district heating system.
Application and technologies for textile sensors production used in pressure distribution measurement - a critical review
Authors: Sofronova Daniela
Published: November 2020

The application of smart textile sensors is continuously expanding with rising new functionalities. Their main task is to report and measure various environmental or human body parameters, such as temperature, humidity, pressure, pH, etc., with direct contact. In this paper an in-depth research and analysis of current developments in the field of textile sensors, designed to report and measure the pressure distribution is made. Application examples in various fields of human activity are presented. Technologies and materials for their production are summarized as well as electronic components for the measurement system designs. The results of the study will be used to develop a new application for these types of sensors to help protecting human health.
Evaluation of stitch length accuracy of embroidery machine by different speed and step
Authors: Sofronova Daniela , Sofronov Yavor
Published: November 2020

The key factor for high quality embroidery is the precision with which the individual stitches are realized in the plane of frame XY. For this purpose, the dispersion in the size of each step on X and Y axes are measured, depending on the step length and the machine speed. The studies were carried out in the entire stroke of the two axes. To evaluate only the positioning error of each individual step the measurements without removing the embroidery fabric from the frame are made in order to eliminate deformations caused by fabric relaxations. The results obtained are particularly relevant for evaluating the ability to produce elements as small as possible.
Using ARAMIS system for measurement of structural stability of running wind tunnel
Authors: Yanovych Viatlii , Duda Daniel
Published: November 2020

Wind tunnels are popularly used to study various aerodynamic phenomena. Their design significantly influences the quality of the created airflow. During the flow generation, the construction parts of the wind tunnel to get deformed due to pressure variations. This phenomenon significantly complicates the creation of high-level laminar flow and worsens the results of experimental studies. The main purpose of this work is to investigate the effect of a sharp change in flow velocity on the structural stability of parts of a wind tunnel with a capacity of 55 kW. For experimental studies, we used the ARAMIS optical measurement system. Using it, we estimated the amount of deformation and mutual displacement of parts of the running wind tunnel at a flow rate of 76 m·s-1.
Flow Behaviour of Inhaled Fibres – Equations of Motion and Preliminary Results of Real Trajectories Recorded by a High-Speed Camera
Authors: Lizal Frantisek , Belka Miloslav , Maly Milan , Cabalka Matous , Jedelsky Jan , Jicha Miroslav
Published: November 2020

The ability to precisely predict the fate of inhaled fibres is important for toxicologists as well as for pharmaceutists struggling to utilize fibres as carriers of a medication. However, the complexity of fibre movement in human airways still represents a significant challenge for programmers of codes for simulation of fibre flow. This conference contribution introduces the theoretical equations of fibre motion which can be used for calculation of the fate of inhaled fibres, and also, in the second part, first results of high-speed camera recorded trajectories of fibres downstream of a realistic human airway bifurcation are presented as an illustration of the real behaviour of fibres in the lungs.
Characterization of Aerosol Nebulized by Aerogen Solo Mesh Nebulizer
Authors: Misik Ondrej , Maly Milan , Cejpek Ondrej , Lizal Frantisek
Published: November 2020

Nebulizers are commonly used devices for inhalation treatment of various disorders. There are three main categories of medical nebulization technology: jet nebulizers, ultrasound nebulizer, and mesh nebulizer. The mesh nebulizers seem to be very promising since this technology should be able to produce aerosol with precisely determined particle size and is easy to use as well [1]. Aerosol generated from the mesh nebulizer Aerogen Solo was measured in this work. Particle size distribution with a mass median of aerodynamic diameter (MMAD) was determined by two different methods.
Unsteady Behaviour of the Effervescent Atomizer
Authors: Mlkvik Marek
Published: November 2020

The effervescent atomizer is a well-established type of the twin-fluid nozzle with internal mixing of fluids. It is popular for the ability to process highly viscous liquids, such as liquid fuels, into a fine spray with low gas consumption. This study aims to investigate the performance of the effervescent nozzle when spraying the liquids with a viscosity up to 308 mPa·s. The working parameters of the nozzle were defined by the mass flows ratio of the gas to the liquid (GLR =2.5 to 20 %) and the gas pressure at the nozzle inlet (Δp = 0.14 MPa). The spray quality was investigated by the laser diffraction system, measuring the spray drop sizes. The investigated nozzle was able to atomize all of the model liquids. However, the liquid viscosity increase led to the need to operate the nozzle with the larger gas consumption. The minimum GLR for the spraying of the liquid with the viscosity 308 mPa·s was 10 %, while the less viscous liquid (60 mPa·s) was processed with the GLR = 2.5 %. It was observed that the spray quality was, at the low GLRs, lowered by unstable nozzle work, caused by the presence of the plug flow in the mixing chamber of the atomizer.
Numerical and CFD Design of Heat Exchanger Used to Biomass Combustion
Authors: Pafcuga Marian , Kapjor Andrej , Hecko David , Vantuch Martin
Published: November 2020

The article describes the design of a heat exchanger used for biomass combustion. The design takes into account simple maintenance of the exchanger, low input costs of construction and the highest possible efficiency. In the design is used the tubular type of heat exchanger. The construction consists of a tubular part - flue gas part, inter-tube space - heat transfer medium space. The output of the numerical model, CFD model is the heat transfer coefficient, heat exchanger power and final comparison of CFD and numerical model outputs.
Experimental and Numerical Investigation of the Thermal Transition Area at the Heated Bottom-Wall of a Horizontal Rectangular Channel
Authors: Pulec Jaroslav , Novosád Jan , Vinš Václav , Dančová Petra
Published: November 2020

This article represents a part of an ongoing work on the preparation of an experimental rectangular channel for the PIV and LIF measurements of vortex structures and temperature field in a non-isothermal water flow. The main aim of the current study is to develop a sufficiently accurate simplified numerical model of the real problem. The basic requirements for thermal properties of heated bottom-wall are specified. In the computational model, there are several simplifications such as 2D case and a constant temperature of a heated surface along the longitudinal coordinate. Results of the numerical simulation of the fluid flow and heat transfer are verified on the experimental data obtained in a laboratory channel with the same geometry and similar flow conditions. The presented results helped to define additional requirements on the design of a new experimental channel intended for investigation of the flow instabilities in a non-isothermal liquid flow.
Numerical Investigation of Source of Oriented Impact Air Flow Using Coanda Effect
Authors: Lenhard Richard , Kaduchová Katarína , Malcho Milan , Ďurčanský Peter , Klačková Ivana
Published: November 2020

The paper deals with the problem with flowing of cooling air using a phenomenon called the Coanda effect. With the help of the designed device, it is possible to generate an oriented air flow for cooling, using the Coanda effect. By means of the formed oriented air stream, it is possible to cool the pipes after heating, i.e. after welding, bending or heat treatment. The experimental part consists of designs and comparisons of design solutions of the device in the program ANSYS Fluent where the analysis of the problem of impact cooling and various device designs and measurement of actual values.
Investigation of a Temperature Field of the Steel Billet 150x150 mm Continuously Cast
Authors: Kavička František , Katolický Jaroslav , Štětina Josef , Mauder Tomáš , Klimeš Lubomír
Published: November 2020

The solidification and cooling of a continuously cast billet and the simultaneous heating of the mold is a very complicated problem of three-dimensional (3D) transient heat and mass transfer. The solving of uch a problem is impossible without numerical models of the temperature field of the concasting itself which it is being processed through the concasting machine (caster). The application of the numerical model requires systematic experimentation and measurement of operational parameters on a real caster as well as in the laboratory. The measurement results, especially temperatures, serve not only for the verification of the exactness of the model, but mainly for optimization of the process procedure. The most important part of the investigation is the measurement of the temperatures in the walls of the mold and the surface of the slab in the zones of secondary and tertiary cooling.
Pump Loss Estimation in Experimental Gas Hydrate Creation Site
Authors: Durcansky Peter , Malcho Milan , Lenhard Richard , Drga Juraj
Published: November 2020

Gas hydrates are considered a global phenomenon that, as an unconventional fossil fuel, can be an alternative energy source for the future. Hydrates form spontaneously in permafrosts and marine sediments, where the conditions for their formation are naturally suitable - low temperature and high pressure. The energy of hydrates could replace or supplement the most commonly used fossil fuels today. Hydrates are also an advantageous solution to the problem of natural gas storage. The main part of the experimental equipment operated is a pump, which generates the pressure energy needed to form hydrates. The article deals with the assessment of the effectiveness of the current state and the estimation of losses in the pipelines of the facility.
Design of an Experimental Device for Simulation of Pipeline Expansion
Authors: Drga Juraj , Holubčík Michal , Gavlas Stanislav
Published: November 2020

This article describes the design of an experimental device for simulating pipe expansion. The device consisted of various variants of compensating elements and types of piping materials. Based on this, a 3D model was developed, together with numerical design calculations of compensators. Subsequently, a more complex analysis was performed by using the CAE Pipe calculation program, which performed calculations of dilatations, forces at fixed points and stresses in the pipeline.
Analysis of Ensuring Thermal Comfort Using an Intelligent Control System
Authors: Kolková Zuzana , Hrabovský Peter , Florková Zuzana , Lenhard Richard
Published: November 2020

Intelligent buildings are productive, energy efficient and environmentally acceptable. Intelligent buildings should be health, permanent and technologically advanced. It is necessary to predict the development and selection of suitable systems for the thermal comfort for ensure of the thermal comfort in the workplace. It is important to analyse how many thermal factors will affect the population, room temperature uniformity, asymmetry of the radiation temperature and turbulence intensity of the flowing air. Thermal comfort is given by the radiant heat, air temperature, air velocity and relative humidity in the room. The main impact of these factors on the comfort level of individuals depends on the type of clothing and on activity. The wrong thermal comfort is detrimental to workers’ health, affects adverse effects on the psyche and increasing the risk of accidents. The thermal comfort of people can be achieved by intelligent management of energy systems in the buildings. The measurement results and settings of intelligent systems are presented in this article.
Prevalence and molecular characterization of Cryptosporidium spp. and Giardia duodenalis in dairy cattle in Gansu, northwest China
Authors: Wang Yilin , Cao Jianke , Chang Yankai , Yu Fuchang , Zhang Sumei , Wang Rongjun , Zhang Longxian
Published: November 2020

Cryptosporidium spp. and Giardia duodenalis are common gastrointestinal parasites with a broad range of hosts, including humans, livestock, and wildlife. To examine the infection status and assess the zoonotic potential of Cryptosporidium spp. and G. duodenalis in dairy cattle in Gansu, China, a total of 1414 fecal samples were collected from the rectum, with one sample collected from each individual animal. All the samples were tested using nested PCR based on the small subunit ribosomal RNA (SSU rRNA) gene of Cryptosporidium spp. and G. duodenalis. The overall infection rates of Cryptosporidium spp. and Giardia duodenalis were 4.2% (n = 59) and 1.0% (n = 14), respectively. Four Cryptosporidium species were identified: C. andersoni (n = 42), C. parvum (n = 12), C. bovis (n = 5), and C. ryanae (n = 1). In further analyses of subtypes of C. parvum isolates based on the 60 kDa glycoprotein (gp60) gene, five were successfully subtyped as IIdA19G1 (n = 4) and IIdA15G1 (n = 1). All 14 G. duodenalis isolates were identified as assemblage E using the triosephosphate isomerase (tpi) gene. The relatively low positive rates of Cryptosporidium spp. and G. duodenalis detected here and the predominance of non-human pathogenic species/assemblages of these parasites indicated their unique transmission dynamics in this area and the low level of threat posed to public health. However, continuous monitoring and further studies of these parasites should be conducted for the prevention and control of these pathogens.
Molecular identification of Trypanosoma brucei gambiense in naturally infected pigs, dogs and small ruminants confirms domestic animals as potential reservoirs for sleeping sickness in Chad
Authors: Vourchakbé Joël , Tiofack Zebaze Arnol Auvaker , Kante Tagueu Sartrien , Mpoame Mbida , Simo Gustave
Published: November 2020

Human African trypanosomiasis (HAT) has been targeted for zero transmission to humans by 2030. Animal reservoirs of gambiense-HAT could jeopardize these elimination goals. This study was undertaken to identify potential host reservoirs for Trypanosoma brucei gambiense by detecting its natural infections in domestic animals of Chadian HAT foci. Blood samples were collected from 267 goats, 181 sheep, 154 dogs, and 67 pigs. Rapid diagnostic test (RDT) and capillary tube centrifugation (CTC) were performed to search for trypanosomes. DNA was extracted from the buffy coat, and trypanosomes of the subgenus Trypanozoon as well as T. b. gambiense were identified by PCR. Of 669 blood samples, 19.4% were positive by RDT and 9.0% by CTC. PCR revealed 150 animals (22.4%) with trypanosomes belonging to Trypanozoon, including 18 (12%) T. b. gambiense. This trypanosome was found in all investigated animal species and all HAT foci. Between animal species or villages, no significant differences were observed in the number of animals harboring T. b. gambiense DNA. Pigs, dogs, sheep and goats appeared to be potential reservoir hosts for T. b. gambiense in Chad. The identification of T. b. gambiense in all animal species of all HAT foci suggests that these animals should be considered when designing new control strategies for sustainable elimination of HAT. Investigations aiming to decrypt their specific role in each epidemiological setting are important to achieve zero transmission of HAT.
L’inclusion scolaire, un enjeu de langage ?
Authors: Pirone Ilaria , Tissot Pascaline
Published: November 2020

À l’appui de différentes expériences de recherche et de formation universitaires dans le champ de l’éducation, cette contribution souhaite pointer comment l’analyse de la diffusion de la novlangue pédagogique fait émerger certains effets des discours soutenant les pratiques scolaires inclusives. Prises entre des formes de protocolisation et d’injonction morales à bien faire, elles risquent de délégitimer le savoir-faire des enseignants. Les rouages de ce qui se transforme parfois en une machinerie inclusive où il faut diagnostiquer pour pouvoir connaître et gérer, peuvent mettre hors-jeu la part de créativité nécessaire à la construction du lien éducatif et produire de nouvelles formes d’exclusion du sujet.
Différences de travail en psychologie clinique entre Mayotte et la France métropolitaine avant et pendant la phase COVID19
Authors: de Brito Amaral Leonor , Permal Sarah
Published: November 2020

Mayotte se trouve actuellement dans une situation de changement identitaire et, par conséquent, de grande transformation. L’évolution des traditions et des comportements à échelle individuelle et sociale pose aux mahorais la question de l’émergence d’une nouvelle identité en accord avec leurs idéaux existants et des valeurs venues de France métropolitaine. Ceci se produit dans un contexte migratoire particulier : plus de moitié de la population de l’île provient d’ailleurs. Tous ces facteurs influencent, évidemment, le travail du psychologue clinicien sur le terrain. Par ailleurs, actuellement, Mayotte est confrontée à une épidémie de coronavirus et de dengue. La gestion de crise dans une île isolée de l’Océan Indien s’avère plus délicate qu’à Paris : elle exige une réadaptation drastique de la part du psychologue clinicien (comme de tous les soignants), compte tenu du contexte social et culturel de l’île.
Endoscopic ultrasound-guided radiofrequency ablation of pancreatic neuroendocrine tumors: a systematic review of the literature
Authors: Imperatore Nicola , de Nucci Germana , Mandelli Enzo Domenico , de Leone Annalisa , Zito Francesco Paolo , Lombardi Giovanni , Manes Gianpiero
Published: November 2020

Background and study aims Surgery is the mainstay therapy for pancreatic neuroendocrine tumors (P-NETs), but it is associated with significant adverse events (AEs). In recent years, endoscopic ultrasound-guided radiofrequency ablation (EUS-RFA) has been described for treating P-NETs. We performed a systematic literature review aimed at exploring the feasibility, effectiveness, and safety of EUS-RFA in treatment of P-NETs.

Methods The literature review was performed in PubMed/MEDLINE, EMBASE, and SCOPUS to identify all case reports of EUS-RFA for treatment of P-NETs.

Results Sixyt-one patients (males 49.2 %, mean age 64.5 years) and 73 tumors (mean size 16 mm, insulinomas 30.1 %) treated with EUS-RFA were included from 12 studies. The overall effectiveness of EUS-RFA was 96 % (75 % – 100 %) without differences between functional vs. non-functional P-NETs (P = 0.3) and without relevant issues about safety (mild AEs 13.7 %). While tumor location was not predictive for incomplete/non-response to EUS-RFA, greater tumor dimensions predicted treatment failure (21.8 ± 4.71 mm in the non-response group vs 15.07 ± 7.34 mm in the response group, P = 0.048). At ROC analysis, a P-NET size cut-off value ≤18 mm predicted response to treatment, with a sensitivity of 80 % (95 % CI 28.4 % – 99.5 %), a specificity of 78.6 % (95 % CI 63.2 % – 89.7 %), a positive predictive value of 97.1 % (95 % CI 84.7 % – 99.9 %) and a negative predictive value of 30.8 % (95 % CI 9.1 % – 61.4 %), with an area under the curve of 0.81 (95 % CI 0.67 – 0.95).

Conclusions EUS-RFA is safe and effective for treating P-NETs. It may be reasonable to consider EUS-RFA for small P-NETs, irrespective of the functional status.
Duodenoscope-associated infection prevention: A call for evidence-based decision making
Authors: Ofstead Cori L. , Buro Brandy L. , Hopkins Krystina M. , Eiland John E. , Wetzler Harry P. , Lichtenstein David R.
Published: November 2020

Background Recent outbreaks of duodenoscope-associated multidrug-resistant organisms (MDROs) have brought attention to the infection risk from procedures performed with duodenoscopes. Prior to these MDRO outbreaks, procedures with duodenoscopes were considered safe and low risk for exogenous infection transmission, provided they were performed in strict accordance with manufacturer instructions for use and multisociety reprocessing guidelines. The attention and efforts of the scientific community, regulatory agencies, and the device industry have deepened our understanding of factors responsible for suboptimal outcomes. These include instrument design, reprocessing practices, and surveillance strategies for detecting patient and instrument colonization. Various investigations have made it clear that current reprocessing methods fail to consistently deliver a pathogen-free instrument. The magnitude of infection transmission has been underreported due to several factors. These include the types of organisms responsible for infection, clinical signs presenting in sites distant from ERCP inoculation, and long latency from the time of acquisition to infection. Healthcare providers remain hampered by the ill-defined infectious risk innate to the current instrument design, contradictory information and guidance, and limited evidence-based interventions or reprocessing modifications that reduce risk. Therefore, the objectives of this narrative review included identifying outbreaks described in the peer-reviewed literature and comparing the findings with infections reported elsewhere. Search strategies included accessing peer-reviewed articles, governmental databases, abstracts for scientific conferences, and media reports describing outbreaks. This review summarizes current knowledge, highlights gaps in traditional sources of evidence, and explores opportunities to improve our understanding of actual risk and evidence-based approaches to mitigate risk.
Incidental detection of colorectal lesions on 18F-FDG-PET/CT is associated with high proportion of malignancy: A study in 549 patients
Authors: Kousgaard Sabrina Just , Gade Michael , Petersen Lars Jelstrup , Thorlacius-Ussing Ole
Published: November 2020

Background and study aims Further diagnostics of incidental colorectal lesions on 18F-fluorodeoxyglucose (FDG) positron emission tomography/computed tomography (PET/CT) is questionable. Therefore, we aimed to evaluate the clinical importance of incidentally detected colorectal lesions on FDG-PET/CT.

Patients and methods In the North Denmark Region, a retrospective study was performed among 19,987 patients who had an FDG-PET/CT from January 2006 to December 2015. Among these patients, we identified patients with a colonoscopy within 12 months from the PET/CT scan and a description of incidental colorectal PET-avid lesions on the PET/CT. PET findings were compared with colonoscopy-detected lesions and eventually histopathology.

Results Incidental PET-avid lesions were observed in 549 patients. Colonoscopy revealed lesions in 457 (83 %), among whom 338 patients had a final histopathological diagnosis. Malignant and premalignant lesions were found in 297 patients (54 % among patients with a PET-avid lesion). The lesions were cancer in 76 patients and adenoma in 221 patients of whom 30 had high-grade and 191 low-grade adenomas. The findings changed patient management in 166 cases (30 % of all patients with a PET-avid lesion). A colonoscopy-based surveillance program was initiated for 80 % of patients with high-grade adenoma. No patients with PET-avid lesions but normal colonoscopy developed colorectal cancer during 3 years of observation (median observation time 7 years).

Conclusions Incidental colorectal FDG uptake was infrequently observed, but when present, it was associated with a high rate of malignant or premalignant lesions. Our results indicate that patients with incidental colorectal FDG uptake should be referred to diagnostic work-up including colonoscopy.
Endoscopic findings of gastric lesions in patients with eosinophilic gastrointestinal disorders
Authors: Fujiwara Yasuhiro , Tanoue Kojiro , Higashimori Akira , Nishida Yu , Maruyama Masatsugu , Itani Shigehiro , Ominami Masaki , Nadatani Yuji , Fukunaga Shusei , Otani Koji , Hosomi Shuhei , Tanaka Fumio , Kamata Noriko , Nagami Yasuaki , Taira Koichi , Machida Hirohisa , Tanigawa Tetsuya , Watanabe Toshio , Ohsawa Masahiko ,   F-Study group
Published: November 2020

Background and study aims Eosinophilic gastrointestinal disorders are classified into eosinophilic esophagitis, eosinophilic gastritis, eosinophilic gastroenteritis, and eosinophilic colitis according to the site of eosinophilic infiltration. Although well established in eosinophilic esophagitis, endoscopic findings in eosinophilic gastritis and eosinophilic gastroenteritis with regard to gastric lesions have not been clearly described. The aim of this study was to identify endoscopic findings of gastric lesions associated with eosinophilic gastrointestinal disorders.

Patients and methods Out of 278 patients with eosinophilic gastrointestinal disorders, 18 had eosinophilic gastritis or eosinophilic gastroenteritis confirmed by biopsy; their endoscopic images were analyzed retrospectively. The association between endoscopic findings and number of eosinophils in the gastric mucosa was investigated.

Results Erythema was most frequently observed (72 %), followed by ulcers (39 %), discoloration (33 %), erosions (28 %), nodularity (28 %), and polyps (28 %). There were several unique endoscopic findings such as submucosal tumor-like deep large ulcers in three patients, antral Penthorum-like appearances (small nodules radially lined toward the pyloric ring) in three patients, “muskmelon-like appearances” (discolored mucosa-composed mesh pattern) in three patients, multiple white granular elevations in two patients, cracks (appearance of furrows similar to those in eosinophilic esophagitis) in five patients, and antral rings in one patient. No significant association was observed between endoscopic findings and number of gastric eosinophils.

Conclusions Several unique endoscopic findings of gastric lesions were observed in patients with eosinophilic gastritis or eosinophilic gastroenteritis. Submucosal tumor-like ulcers, antral Penthorum-like appearances, muskmelon-like appearances, and cracks might be associated with eosinophilic gastrointestinal disorders.
Implementierung der Behandlung durch enzymatisches Debridement bei Verbrennungen – Ergebnisse eines interprofessionellen, deutschsprachigen Expertenworkshops
Authors: Ziegler Benjamin , Corterier Cord , Kremer Thomas , Lumenta David B. , Plock Jan A. , Richter Sandy , Sander Frank , Schiefer Jennifer L. , Siegwart Laura C. , Stauder Martin , Wallner Christoph , Wiechmann Dirk , Hirche Christoph
Published: November 2020

Einleitung Das enzymatische Debridement (ED) auf Bromelain-Basis (Nexobrid®) wird seit seiner Markteinführung 2013 zunehmend in Verbrennungszentren eingesetzt. Die Literatur belegt die Effizienz der Escharentfernung sowie eine Überlegenheit im Vergleich zum Standard-of-Care in Bezug auf periprozeduralem Blutverlust und Notwendigkeit operativer Maßnahmen. Während ausreichende Erfahrung eine zuverlässige Anwendung ermöglicht, müssen zur Implementierung der Technik einige praktische und logistische Hürden überwunden werden, die weder in den Herstellerangaben noch in der verfügbaren Literatur ausreichend beschrieben sind.

Methode Ein multiprofessionelles Panel, bestehend aus erfahrenen Anwendern aus deutschsprachigen Brandverletztenzentren, wurde zu einem Expertenworkshop eingeladen. Vorab wurden mit den Teilnehmern Themenkomplexe aus den Bereichen Indikationsstellung, Definition von Behandlungspfaden, praktische Durchführung des enzymatischen Debridements, Nachbehandlung sowie Komplikationen abgestimmt, um diese im Rahmen des Expertenworkshops zu erörtern.

Ergebnisse Zu den vordefinierten Themenkomplexen wurden konkrete Handlungsempfehlungen im Expertenpanel erarbeitet und konsentiert. Zusammenfassende Kernaussagen wurden zusätzlich herausgestellt. Sie richten sich sowohl an Einsteiger als auch an erfahrenere Anwender und bieten Unterstützung, um möglichst optimale Ergebnisse durch ED zu erzielen. So entstanden unter anderem Hinweise für den Einsatz von ED über klassische Indikationen hinaus, unterschiedliche Behandlungspfade je nach Verbrennungstiefe und Verlauf des ED mit jeweils angepasster Nachbehandlung, Management von Therapieversagen sowie Empfehlungen hinsichtlich infrastruktureller Rahmenbedingungen zur Implementierung von ED.

Diskussion Obwohl die Wirksamkeit von ED durch die vorhandene Literatur belegt und eine Überlegenheit hinsichtlich mehrerer Aspekte der Behandlung von Verbrennungswunden gezeigt werden konnte, sind bislang nur wenige anwenderorientierte Empfehlungen zur praktischen Implementierung von ED verfügbar. Wenngleich die hier publizierten Handlungsempfehlungen und Expertenaussagen nur zum Teil durch Evidenz aus eindeutigen Studien zu untermauern sind, basieren sie dennoch auf der gebündelten Erfahrung des Expertenpanels, die die Anzahl der bisher publizierten Fälle um ein Vielfaches übertrifft und dadurch erlaubt, wertvolle Unterstützung bei der erfolgreichen Implementierung der Technik bereitzustellen.
Does SGLT2 Inhibition Affect Sympathetic Nerve Activity in Type 2 Diabetes?
Authors: Dimova Rumyana , Tankova Tsvetalina
Published: November 2020

SGLT2 inhibitors increase renal glucose excretion and thus decrease both fasting and postprandial plasma glucose levels. The effects of SGLT2 inhibition outweigh those on glycemic control and are also associated with the induction of hemodynamic changes that improve cardiovascular and renal function in people with type 2 diabetes. The exact mechanisms have not yet been completely clarified. This review is focused on the potential relationship between SGLT2 inhibition and sympathetic nerve activity. There is accumulating evidence for a suppressive effect of SGLT2 inhibitors on the sympathetic nerve tone, which might be a putative mechanism for cardiovascular protection in subjects with type 2 diabetes.
Clival Meningioma Removal through a Suboccipital Retrosigmoid Approach: Operative Video and Technical Nuances
Authors: Candanedo Carlos , Moscovici Samuel , Spektor Sergey
Published: November 2020

Background Clival meningiomas are challenging lesions that need to be managed according to the displacement of the adjacent structures. Lateral skull base approaches are needed to achieve their radical removal; however, they are associated with significant morbidity, especially when the tumor involves the basilar artery, its perforators, brainstem, and lower cranial nerves.

Design This is a case of a 79-year-old female patient, diagnosed with a large lower clival meningioma after suffering from headaches. It was offered a conservative treatment but on serial MRI, an increase in the meningioma's size was observed, so it was decided to remove the meningioma using a left suboccipital retrosigmoid approach.

Settings On a left three-quarter prone position, with facial nerve, auditory brainstem response, lower cranial nerves, and motor-evoked potentials and somatosensory-evoked potentials neurophysiologic monitoring, a right suboccipital retrosigmoid craniotomy with opening of the foramen magnum was performed, giving enough lateral visualization of the tumor. Broad base tumor pushing backward and aside the vertebral and basilar arteries, cranial nerves (7th–12th), and the brainstem was exposed and removed.

Results Near total resection of the meningioma was achieved, leaving a microscopic residual in the entry points of the low cranial nerves without complications. There was no neurological deficit after the surgery. Postoperative MRI revealed no signs of residual tumor.

Conclusion: In this case, the regular retrosigmoid approach, extended into the foramen magnum was enough for the removal of this pure clival meningioma.

The link to the video can be found at: https://youtu.be/3d6Uj4gjmDU.
Far Lateral Approach for Malignant, Severely Calcified Cerebellopontine Angle Tumor
Authors: Kiyofuji Satoshi , Graffeo Christopher S. , Perry Avital , Link Michael J.
Published: November 2020

Background The far-lateral approach is an effective skull base technique that provides access to the lower clivus and premedullary area. This approach is also useful for maximal visualization and resection of large posterior fossa tumors with extensive medial extension, especially when aggressive resection is ideal for a malignant tumor in a young patient, or it is technically challenging because of tumor calcification. We demonstrate a microsurgical operative video to describe technical pearls in this difficult situation.

Case Presentation A 45-year-old man with history of “hoarseness” for up to two decades was presented with imbalance and mild dysphagia over 3 years. Imaging demonstrated a 55-mm left cerebellopontine angle (CPA) tumor extending medially across the midline with severe calcification (Figs. 1 and 2). His neurological examination revealed left facial numbness, complete left facial weakness, left deafness, complete left vocal paralysis, as well as severe left hemibody ataxia. The tumor was resected via a left suboccipital craniotomy with far lateral approach including drilling to the occipital condyle and C1 laminectomy. Initial manipulation of the inferior pole of the tumor resulted in asystole which was managed successfully with glycol pyrolate. Pathology demonstrated IDH-1 wild type, MGMT-methylated glioblastoma. The patient subsequently underwent adjuvant chemoradiation.

Conclusion The far-lateral approach is an effective approach for maximal safe resection of a malignant brainstem, cerebellar, and CPA tumor.

The link to the video can be found at: https://youtu.be/AIGebJPJEnw.
Clinical Outcomes of Incidental Venous Thromboembolism in Cancer and Noncancer Patients: The SWIss Venous ThromboEmbolism Registry (SWIVTER)
Authors: Spirk David , Sebastian Tim , Barco Stefano , Banyai Martin , Beer Jürg H. , Mazzolai Lucia , Baldi Thomas , Aujesky Drahomir , Hayoz Daniel , Engelberger Rolf P. , Kaeslin Thomas , Korte Wolfgang , Escher Robert , Husmann Marc , Blondon Marc , Kucher Nils
Published: November 2020

Objective In patients with cancer-associated venous thromboembolism (VTE), the risk of recurrence is similar after incidental and symptomatic events. It is unknown whether the same applies to incidental VTE not associated with cancer.

Methods and Results We compared baseline characteristics, anticoagulation therapy, all-cause mortality, and VTE recurrence rates at 90 days between patients with incidental (n = 131; 52% without cancer) and symptomatic (n = 1,931) VTE included in the SWIss Venous ThromboEmbolism Registry (SWIVTER). After incidental VTE, 114 (87%) patients received anticoagulation therapy for at least 3 months. The mortality rate was 9.2% after incidental and 8.4% after symptomatic VTE for hazard ratio (HR) 1.10 (95% confidence interval [CI] 0.49–2.50). After adjustment for competing risk of death, recurrence rate was 3.1 versus 2.8%, respectively, for sub-HR 1.07 (95% CI 0.39–2.93). These results were consistent among cancer (mortality: 15.9% vs. 12.6%; HR 1.32, 95% CI 0.67–2.59; recurrence: 4.8% vs. 4.7%; HR 1.02, 95% CI 0.30–3.42) and noncancer patients (mortality: 2.9% vs. 2.1%; HR 1.37, 95% CI 0.33–5.73; recurrence: 1.5% vs. 2.3%; HR 0.63, 95% CI 0.09–4.58). Patients with incidental VTE who received anticoagulation therapy for at least 3 months had lower mortality (4% vs. 41%) and recurrence rate (1% vs. 18%) compared with those who did not.

Conclusion In SWIVTER, more than half of incidental VTE events occurred in noncancer patients who often received anticoagulation therapy. Among noncancer patients, early mortality and recurrence rates were similar after incidental versus symptomatic VTE. Our findings suggest that anticoagulation therapy for incidental VTE may be beneficial regardless of the presence of cancer.
Autonomous materials synthesis by machine learning and robotics
Authors: Shimizu Ryota , Kobayashi Shigeru , Watanabe Yuki , Ando Yasunobu , Hitosugi Taro
Published: November 2020

Future materials-science research will involve autonomous synthesis and characterization, requiring an approach that combines machine learning, robotics, and big data. In this paper, we highlight our recent experiments in autonomous synthesis and resistance minimization of Nb-doped TiO2 thin films. Combining Bayesian optimization with robotics, these experiments illustrate how the required speed and volume of future big-data collection in materials science will be achieved and demonstrate the tremendous potential of this combined approach. We briefly discuss the outlook and significance of these results and advances.