bluuebunny/crossref_metadata_2025 huggingface dataset:
3D printing of rock analogues in sand: a tool for design and repeatable testing of geomechanical and transport properties
Authors: Hodder Kevin , Ishutov Sergey , Sanchez Angel , Zambrano Gonzalo , Chalaturnyk Rick
Published: November 2020

Natural rocks can be heterogeneous due to complex diagenetic processes that affect mineralogy and pore architecture. Correlation of geomechanical and transport properties of rocks in three dimensions can lead to large variances in data when tested experimentally. 3D-printing of rock analogues in sand is a promising alternative for experimental testing that can be used to calibrate variables during geotechnical testing. While 3D-printed sand is a homogeneous material, the parameters for creating grain packing and pore infill can be tuned to mimic specific geomechanical and transport properties. Initially, 3D-printed specimens have a low density due to a loose distribution of grains. Herein, we present our efforts at increasing the density through incorporating a roller in the printing process to compact individual layers. We also propose introduction of a more heterogeneous sand mixture that encompasses a wide range of grain-size distributions. Lastly, a discussion between binder saturation (that infills the pore space) of 3D-printed specimens and the axial strength, dimensional control, and porosity is described within. 3D printing of rock analogues is critical in pursuing rigorous destructive tests required for geotechnical and geological engineering because it can provide repeatable, controlled data on rock properties.
Group effects in urban shallow geothermal energy
Authors: de Sauvage Jean , Regnicoli Benitez Bruno , Szymkiewicz Fabien , Badinier Thibault
Published: November 2020

Since the 1980’s, shallow geothermal solutions have been developed whose principle is to attach heat exchange pipes to the reinforcing cages of geotechnical structures. These low energy solutions combining a structural and a thermal role allow the fulfilling of the heating and cooling needs of buildings for a very low carbon cost. Energy geostructures are often placed in a groundwater flow. On one hand, it is a good way to avoid any multiyear thermal shift since the heat excess or default is tempered through the advection. This advection creates a thermal plume and heat waves in the soil can interact with downstream structures whose behaviour can be affected. The understanding of these interactions is essential for a smart management of the shallow geothermal development at the city scale. To study these interactions, a group of nine energy piles has been studied in Sense City, a mini city where a specific climate can be imposed and the underground water flow can be controlled. A numerical hydraulic-thermal coupled model was developed with the FEM software CESAR-LCPC to extrapolate the results. The combination of experimental and numerical models provides helpful results for the definition of guidelines concerning the prevention of interactions.
Thermal response of energy soldier pile walls
Authors: Zhong Yu , Narsilio Guillermo , Makasis Nikolas , Li Zhangshun , Aditya Gregorious
Published: November 2020

Utilising foundation systems as heat exchangers has received significant public interest worldwide, as these energy geo-structures can constitute a clean, renewable, and economical solution for space heating and cooling. Despite their potential, the thermal performance of energy retaining walls, especially soldier pile walls, has not been sufficiently studied and understood and thus further research is required. This work utilises the first ever energy soldier pile wall in the currently under-construction Melbourne CBD North metro station as a case study. A section of this wall has been instrumented and monitored by the University of Melbourne. Full scale thermal response tests (TRTs) have been conducted on a single thermo-active soldier pile at two different excavation levels. Thermal response testing field data results are presented in terms of mean fluid temperatures and further analysed to show the potential impact of the excavation level on the structure’s thermal performance. To further explore this impact of excavation depth (or pile embedment depth) and the long-term thermal performance of energy pile walls, a detailed 3D finite element numerical model is developed in COMSOL Multiphysics and validated against the field-testing results. The simulation suggests that thermally activating all the soldier piles in the station can provide enough energy to fulfil the heating and cooling demand of the station and to satisfy partial heating demand to the surrounding buildings. Furthermore, results suggest that current energy pile design approaches may be adapted for designing energy pile walls.
Investigations into thermal resistance of tunnel lining heat exchangers
Authors: Shafagh Ida , Rees Simon , Loveridge Fleur
Published: November 2020

Geothermal energy is a promising and sustainable source that can reduce current dependence on conventional fuels for thermal energy production. To exploit this source of energy thermo-active geostructures such as tunnel lining heat exchangers are being investigated theoretically as well as experimentally. These geostructures are composed of concrete panels embedded with reinforcement cages fitted with absorber pipes. Several engineering projects in China, Finland and Italy have deployed such heat exchangers in tunnels. To achieve efficient energy production, characterisation of these systems require realistic models of the substructure heat exchanger. Therefore investigations into thermal resistance of the heat exchanger is vital. The present study is concerned with quantifying the thermal resistance of tunnel lining heat exchangers where the thermal boundary surfaces are applied at surfaces representing the adjacent ground and the exposed concrete, in addition to the pipe surface. Steady state temperature distribution in a two dimensional cross section of a tunnel lining heat exchanger is investigated using the boundary collocation least squares method. Design parameters including pipe and tunnel lining specifications are used as model inputs.
Analytical solution for describing the thermo-mechanical behavior of plane energy geostructures
Authors: Rotta Loria Alessandro F. , Zannin Jacopo , Llabjani Qazim , Laloui Lyesse
Published: November 2020

Over the past twenty years, a substantial amount of research has been performed to expand the modeling capabilities of energy geostructures: innovative earth-contact structures that provide combined structural support and renewable energy supply. Several analytical and semi-analytical solutions have been made available for describing the thermo-mechanical behavior of cylindrical energy geostructures such as energy piles. However, no analytical solutions for capturing the thermo-mechanical behavior of plane energy geostructures such as energy walls and slabs have been developed until recently. This paper summarizes the essential features of the first analytical solution available for describing the thermo-mechanical behavior of plane energy geostructures. This analytical solution extends Winkler’s model for a beam resting on an elastic soil mass to non-isothermal conditions, allowing to quantify the effects of temperature variations, axial loads, transversal loads and bending moments applied to plane energy geostructures. Such an analytical solution can be used in the analysis of an elementary unit represented by a single beam as well as complex plane energy geostructures using the superposition principle. Based on the preceding capabilities, the proposed analytical solution may effectively serve the analysis or design of plane energy geostructures under the influence of mechanical and/or thermal loads.
Life cycle sustainability assessment of geothermal heating and cooling system: UIC case study
Authors: Reddy Krishna R. , Ghimire Sanjeeta N. , Wemeyi Emmanuelle , Zanjani Roya , Zhao Liang
Published: November 2020

This study presents a sustainability assessment of geothermal heating and cooling system of three buildings at the University of Illinois at Chicago - Grant, Lincoln, and Douglas Halls based upon the triple bottom line sustainability framework and presents a comparison between geothermal and conventional heating and cooling systems. Life cycle assessment (LCA) was performed to evaluate and quantify the environmental impacts for both geothermal and conventional systems. Similarly, economic impacts were evaluated by making a comparison between direct and indirect costs of both systems. Indirect costs were calculated using Stepwise 2006 incorporated in monetized LCA and compared that cost with social cost of carbon. Social impacts were quantified using Social Sustainability Evaluation Matrix (SSEM) which covers four major dimensions of society: social-individual, socio-institutional, socio-economic, and socio-environmental. An overall sustainability index for geothermal system and conventional system was calculated by evaluating environmental, economic, and social impacts using Integrated Value Model for Sustainability Assessment (MIVES) methodology. The results show that the geothermal heating and cooling system is more sustainable and environmentally friendly than the conventional system.
Modeling of shallow, horizontal, unsaturated, ground-based heat exchangers with consideration of dry zone formation
Authors: Oh Hyunjun , Tinjum James M.
Published: November 2020

High fluid temperatures in ground-based heat exchangers (GHXs) during the cooling season may result in a decrease in thermal conductivity of adjacent backfill (λbackfill), potentially causing degradation in the performance efficiency of the GHX system. In this study, numerical modeling was performed using the SVOffice™ finite-element software to evaluate coupled heat and moisture transfer around two GHXs. Constant-temperature boundary conditions of 35 ºC were applied to the GHX surfaces, and thermal properties of the backfill were controlled for comparisons. For estimate typical hydraulic and thermal properties for the modeling, laboratory tests and literature review were performed. Modeling results indicate that coupled heat and moisture transfer occurs rapidly near the GHX involving a dry zone formation when λbackfill decreases. A boundary between dry and wet zones where soil thermal properties rapidly change was observed around 50% GHX temperature dissipated (T50), and accordingly T50 was used to optimize the pipe configuration. Coupled heat and moisture transfer increased when the GHX configurations were optimized with consideration of dry zone formation. These results imply that thermally enhanced, engineered backfill and optimized configurations can enhance GHX system efficiency.
Thermal volume changes of saturated sand during loading-unloading-heating phase
Authors: Liu Hong , McCartney John S. , Xiao Yang
Published: November 2020

The influence of temperature on the volume change of loose, saturated sand was assessed through a series of temperature-controlled hollow-cylinder triaxial tests. The sand specimens were isotropically compressed and unloaded to induce an overconsolidation effect, then subjected to drained heating. During drained heating, water was expelled from the sand specimens and the thermally-induced axial and volumetric strains were negative, reflecting isotropic expansion.
The use of hyperbolic and Asaoka’s methods to estimate the moisture diffusivity and the hydraulic conductivity of unsaturated soils from tests to determine the SWRC
Authors: Asanza Enrique , Pardo de Santayana Fernando , Martín-Ruiz Miriam
Published: November 2020

The equation governing the unsaturated transient flow in a soil sample when subjected to suction (ψ) at its base and that of the classical 1-D consolidation are exactly alike (equation of diffusion). The former can be arrived at by Richards’ equation, being in this case the moisture diffusivity (D), instead of the coefficient of consolidation (cv), the governing parameter. D need not be constant, but rather a function of the volumetric water content, D=D(θ), and is defined as the ratio of the hydraulic conductivity, k(θ), over the specific water capacity, C(θ)=dθ/dψ, i.e., the slope of the SWRC. The hyperbolic method has been used for several geotechnical purposes and, most importantly, as an alternative to Asaoka’s method for predicting the final settlement and cv of soft soils undergoing consolidation, improved by preloading. This paper shows that both methods prove to be very useful as a means of obtaining D(θ) and k(θ) at a certain range of θ, provided that a reduced number of water contents at known elapsed times are determined over the medium stage of this transient flow. It is addressed in the paper both by theoretical grounds and on the light of experimental data of 4 soils.
Particle-fluid flow and transport within rough fractures
Authors: Yamashiro Brian , Tomac Ingrid
Published: November 2020

Proppant injection is an important part of a hydraulic fracturing programs in which fluid-particle slurry is injected into rock fractures. Injected particles are lodged between fracture surfaces during wall close-in thereby propping open the fracture, improving connectivity and production. This paper investigates behaviour of proppant particles within artificially generated rock fractures, providing insight into transport behavioural differences caused by realistic surface roughness. Better understanding of proppant behaviour within more realistic rough fracture conditions provides greater understanding of proppant transport as compared to past works where smooth walled fracture configurations were utilized. A clearer understanding is important in providing more accurate evaluation of realistic proppant flow and distribution and improving injection design. In this study a roughened surface, analogues to actual rock fracture surface, is artificially generated based on a rock surface’s fractal dimension and asperity height standard deviation. Computational representation of the rock surfaces and flow domain is generated. Resolved Discrete Element Method coupled with computational fluid dynamics (DEM-CFD) is implemented in this study to evaluate proppant particle transport behaviour within the fractures. This work highlights importance of considering fracture surface roughness in evaluating proppant flow and transport and more generally the impact of rough boundary conditions of particle-fluid systems.
Micromechanical interpretation of thermo-plastic behaviour of clays
Authors: Casarella Angela , Tarantino Alessandro , Di Donna Alice
Published: November 2020

The effect of temperature on mechanical behaviour of clay-based geomaterials is relevant in a number of geotechnical applications (e.g. low enthalpy geothermal systems and energy geostructures, nuclear waste disposal, and heating in rapid shear deformation). Mechanical response of (saturated) clays upon heating is not always intuitive as volume changes may occur due to both thermal expansion of clay constituents and temperature-induced changes of clay microstructure. This paper first revisits the macroscopic thermally-induced mechanical behaviour of saturated clays available in the literature via an advanced thermo-elastoplastic constitutive model and then elucidates the dependence on clay mineralogy of the two key parameters of the model (mechanical hardening and thermal softening respectively) by inspecting differences in clay inter-particle electro-chemical forces occurring in kaolinitic, illitic, and smectitic clays. The micromechanically-based interpretation of constitutive parameters can serve as a guidance for soil parameter selection in the design of energy geostructures.
Laboratory tests on arsenic leaching from excavated shale rock by elevated temperatures
Authors: Takai Atsushi , Iwata Yusuke , Gathuka Lincoln W. , Katsumi Takeshi
Published: November 2020

This manuscript focuses on the leaching of geogenic arsenic (As) from shale rock at different temperatures. In Japan, the utilisation of geogenic contaminated soils and rocks for construction such as in embankment is much encouraged. Therefore, when applying thermally active geo-systems such as thermal energy storage and ground-source heat pump, which are associated with ground temperature changes, we need to know its impact on the leaching behaviour of such contaminated geomaterials. In this study, the leaching of chemicals from an excavated shale rock containing geogenic As was assessed using a shaking and non-shaking batch test. In those experiments, different temperatures up to 40 ºC and contact times ranging from 6–360 h were employed. Overall, it was found out that more As was leached with elevated temperatures and its concentration was notably higher under the non-shaking condition. Further, under the non-shaking condition, its concentration was highest at 40 ºC with contact time of 360 h, whereby ca. 0.06 mg/L As was leached, which is 6 times the permissible limit of 0.01 mg/L in Japan.
Material Balance of Fuel Cycles for Plutonium Recycling in Pressurised Water Reactors
Authors: Mancheva Zlatina , Naydenov Ivaylo
Published: November 2020

An inevitable effect of uranium fuel operation is the production of plutonium. Its increasing inventory requires adoption of plutonium management strategy. The option that can provide inventory minimization and utilization of plutonium’s energy content is its usage as nuclear fuel. Since the most common power reactors are the pressurized water reactors, the current paper examines the material balance of several fuel cycles for single and multiple plutonium recycle in a reference PWR. Once-through fuel cycle’s balance has been used as a benchmark. Plutonium production and consumption rates, uranium and separative work requirements have been evaluated for four fuel cycle variations. The results affirm the overall long-term feasibility of multiple plutonium recycle in PWRs in terms of increased plutonium consumption.
Model of a building heating system with renewable energy sources
Authors: Komitov Nicolay , Shopov Nicolay , Rasheva Violeta
Published: November 2020

The current century is characterized by an increasing use of renewable energy - wind farms, solar parks, bio fuels, etc. Climate change and rising prices of fossil fuels lead to increased investment in renewable energy. This raises the need to examine the impact of various factors on the efficiency of energy production from renewable energy sources. This is related to the development of adequate models and the implementation of appropriate computer systems to manage and control these processes. The present work presents the main aspects of the modelling of a building heating installation using renewable energy sources - a solar photovoltaic panel and a HHO gas generator. The additional energy needed to heat the building is provided by a pellet boiler. An energy balance of the studied building is made taking into account the external and internal temperatures and energy loss. The computer model was developed in order to build a system for process control in the building’s heating system.
A CFD analysis of the performance characteristics of different Darrieus turbine runners
Authors: Iliev Rossen
Published: November 2020

This paper presents the capabilities of analyzing different Darrieus wind turbine runners with the computer program Ansys Fluent. A K-omega turbulence model was used in the case of a two-dimensional flow with a suitable computational grid around the profile of the blades. The obtained theoretical performance characteristics were validated on test rig №7 (Wind Turbines) in the Laboratory of Hydropower and Hydraulic Turbomachinery (HEHT Lab) at the Technical University of Sofia. The data analysis shows that it’s possible to predict the performance characteristic and the optimum operating regime of the Darrieus wind turbine.
Development of Wind Energy and the Installed Wind Power Plants in Turkey
Authors: Genç Cansev , Sakalli Abdulla , Stoyanov Ivaylo , Iliev Teodor , Mihaylov Grigor , Beloev Ivan
Published: November 2020

This article analyses the development of wind energy in Turkey - the number and capacity of installed wind generators, as well as the generated electricity. It was established that the number of wind power plants is 99 with a total installed capacity of 3933 MW, and the amount of electricity produced by wind power plants is 17909.3 GWh / year. Turkey has been shown to have great potential for developing electricity generation from offshore wind farms. The increase in the number of offshore wind turbines in the coming years is expected to increase the relative share of renewable sources in the country’s energy mix, to contribute to the technological and industrial development of the regions, to produce electricity from renewable and environmentally friendly sources and to reduce the country’s energy dependence. It has been established that there are appropriate conditions in Turkey for the development of wind energy and preconditions have been created for achieving the target for promoting the use of renewable energy sources by 2023.
Parametric Optimization of Electrohydraulic Servo System
Authors: Ormandzhiev Krasimir , Yordanov Stanimir , Mihalev Georgi , Kostov Krasen
Published: November 2020

The electrohydraulic servo systems used in the industrial production are characterized by relatively simple construction, easy operation and high speed, good reliability, functional flexibility and low cost. All this demonstrates the need to study the performance of electrohydraulic servo system primarily in dynamic operating modes. The article studies a mathematical model of electrohydraulic servo system with the typical nonlinearities. The parametric optimization of the automatic PID controller was performed on the basis of minimizing the integral quality criterion when comparing reference and experimental transient processes. The obtained results are shown in a graphical form.
Simulation of Steady States of Helium Loop at Long Time Scenarios
Authors: Világi František , Knížat Branislav , Olšiak Róbert , Mlkvik Marek , Mlynár Peter , Ridzoň František , Urban František
Published: November 2020

The natural circulation helium loop is an experimental facility designed for the research of the possibility of utilizing natural convection cooling for the case of decay heat removal from a fast nuclear reactor. This concept would bring an improved automated safety system for future nuclear power plants operating a gas-cooled reactor. The article presents a new possibility of direct use of energy conservation laws in a 1D simulation of natural circulation loops. The calculation is performed by a triple iteration process, nested into each other. The results of the calculations showed good agreement with the measurements at steady state. A calculation with the proposed model at unsteady state is not yet possible, especially because of the exclusion of heat accumulation into the material.
Numerical Simulation of Heat Transfer Using Cooling Roof Panels
Authors: Kaduchová Katarína , Lenhard Richard , Malcho Milan
Published: November 2020

Roof cooling can be used in coffered roofs, acoustic panels, as active cooling plasterboard attached to a standard metal structure designed for lowered roofs, or as a system of cooling register under the plaster. The roof cooling system works on the principle of heat transfer through a large active area and there is no unpleasant air flow than with conventional air conditioning. For technological reasons, very often pipes with a heat transfer medium are attached to a sheet metal of various materials, the thermokinetic properties of which significantly influence the intensity of the heat flux dissipated by the cooling system. The paper presents a numerical analysis of heat transport using stainless steel and aluminium sheets as the supporting sheet, as well as the influence of different ways of installing large panels under the roof.
Numerical Investigation of Aeroelastic Flutter in Two-Dimensional Cascade of Compressor Blades
Authors: Fürst Jiří , Lasota Martin , Musil Josef , Pech Jan
Published: November 2020

Following contribution presents numerical study of aeroelastic flutter in two-dimensional section of flat wing cascade in wind tunnel. The investigation is conducted as a parametric study of varying pitch angle of one (middle) blade in the cascade with each computational case performed on fixed computational grid. This approach can be viewed as an approximation of fluid-structure interaction realized on moving mesh. Numerical predictions were carried by means of CFD open-source codes OpenFOAM® and Nektar++. The particular aim was focused on assessment of numerical performance and accuracy of the numerical solvers as well as several turbulence models.
Pour que l’éducation soit au rendez-vous dans l’inclusion scolaire
Authors: de Lajonquière Léandro
Published: November 2020

L’idée de scolariser des enfants en situation de handicap est le résultat d’un long processus qui, d’une certaine manière, a démarré avec l’éducation de « l’enfant sauvage » de l’Aveyron entreprise par Jean Itard, aux antipodes du nihilisme éducatif exprimé à l’époque par Philippe Pinel. Cependant, notre façon habituelle de concevoir l’inclusion scolaire des enfants dits autistes n’est pas vraiment à la hauteur des nobles intentions éducatives attendues. Nous revenons sur les développements de Maud Mannoni sur la prise en charge institutionnelle des enfants « en situation de handicap » afin de présenter quelques éléments qui mettent en valeur l’enjeu éducatif subjectivant dans tout processus d’inclusion scolaire.
Fuzzy-rough multi-objective product blending fixed-charge transportation problem with truck load constraints through transfer station
Authors: Ghosh Shyamali , Roy Sankar Kumar
Published: November 2020

In this contribution, for the first time, an efficient model of multi-objective product blending fixed-charge transportation problem with truck load constraints through transfer station is formulated. Transfer station inserts transfer cost and type-I fixed-charge. Our aim is to analyze an extra cost that treats as type-II fixed-charge and truck load constraints in the designed model that required when the amount of items exceeds the capacity of vehicle for fulfilling the shipment by more than one trip. Type-II fixed-charge is added with transportation cost and other cost from transfer station. We consider here an important issue of the multi-objective transportation problem as product blending constraints for transporting raw materials with different purity levels for customers’ satisfaction. In realistic point of view, the parameters of the model are imprecise in nature due to existing several unpredictable factors. These factors are apprehended by incorporating the fuzzy-rough environment on the parameters. Expected-value operator is utilized to derive the deterministic form of fuzzy-rough data, and the model is experienced with help of fuzzy programming, neutrosophic linear programming and global criteria method. Two numerical examples are illustrated to determine the applicability of the proposed model.
Tränenwegsstenosen im Erwachsenenalter
Authors: Heichel Jens , Struck Hans-Gert
Published: November 2020

Zur Aufrechterhaltung der okulären Oberflächenhomöostase und damit den Erhalt der optischen Eigenschaften sind Tränenproduktion, -verteilung und -abtransport essenzielle physiologische Funktionen. Störungen dieser funktionellen Einheit gehen mit starken Beschwerden und einem hohen Leidensdruck bei den Patienten einher. Da etwa 3% unserer Patienten eine Tränenabflussstörung aufweisen, ist die Thematik von hohem klinischem Interesse.
International Comparison of Six Basic eHealth Indicators Across 14 Countries: An eHealth Benchmarking Study
Authors: Ammenwerth Elske , Duftschmid Georg , Al-Hamdan Zaid , Bawadi Hala , Cheung Ngai T. , Cho Kyung-Hee , Goldfarb Guillermo , Gülkesen Kemal H. , Harel Nissim , Kimura Michio , Kırca Önder , Kondoh Hiroshi , Koch Sabine , Lewy Hadas , Mize Dara , Palojoki Sari , Park Hyeoun-Ae , Pearce Christopher , de Quirós Fernan G. B. , Saranto Kaija , Seidel Christoph , Vimarlund Vivian , Were Martin C. , Westbrook Johanna , Wong Chung P. , Haux Reinhold , Lehmann Christoph U.
Published: November 2020

Background Many countries adopt eHealth applications to support patient-centered care. Through information exchange, these eHealth applications may overcome institutional data silos and support holistic and ubiquitous (regional or national) information logistics. Available eHealth indicators mostly describe usage and acceptance of eHealth in a country. The eHealth indicators focusing on the cross-institutional availability of patient-related information for health care professionals, patients, and care givers are rare.

Objectives This study aims to present eHealth indicators on cross-institutional availability of relevant patient data for health care professionals, as well as for patients and their caregivers across 14 countries (Argentina, Australia, Austria, Finland, Germany, Hong Kong as a special administrative region of China, Israel, Japan, Jordan, Kenya, South Korea, Sweden, Turkey, and the United States) to compare our indicators and the resulting data for the examined countries with other eHealth benchmarks and to extend and explore changes to a comparable survey in 2017. We defined “availability of patient data” as the ability to access data in and to add data to the patient record in the respective country.

Methods The invited experts from each of the 14 countries provided the indicator data for their country to reflect the situation on August 1, 2019, as date of reference. Overall, 60 items were aggregated to six eHealth indicators.

Results Availability of patient-related information varies strongly by country. Health care professionals can access patients' most relevant cross-institutional health record data fully in only four countries. Patients and their caregivers can access their health record data fully in only two countries. Patients are able to fully add relevant data only in one country. Finland showed the best outcome of all eHealth indicators, followed by South Korea, Japan, and Sweden.

Conclusion Advancement in eHealth depends on contextual factors such as health care organization, national health politics, privacy laws, and health care financing. Improvements in eHealth indicators are thus often slow. However, our survey shows that some countries were able to improve on at least some indicators between 2017 and 2019. We anticipate further improvements in the future.
Discovery of Comorbid Psychiatric Conditions among Youth Detainees in Juvenile Justice System using Clinical Data
Authors: Islam Humayera , Mosa Abu S. M. , Srivastava Hirsch K. , Mandhadi Vasanthi , Rajendran Dhinakaran , Young-Walker Laine M.
Published: November 2020

Objective The main aim was to analyze the prevalence and patterns of comorbidity in 11 identified broad categories of psychiatric conditions and 48 specific psychiatric conditions among 613 youth from the Missouri Division of Youth Services (DYS) residential sites using advanced data mining techniques on clinical assessment data.

Methods This study was based on youth detainee population at DYS residential placements receiving psychiatric care through the telemedicine network established between DYS and University of Missouri Department of Psychiatry. Association Rule Mining (ARM) algorithm was used to determine the associations and the co-occurrence pattern among the comorbid psychiatric conditions.

Results About 88% of the DYS youth are diagnosed with two or more psychiatric disorders. From the ARM analysis, the most commonly co-occurred disorders are obtained as substance-related or -addicted disorders (SUD) and disruptive, impulse-control, and conduct disorders (CD) (n [%] = 258 [42.1%], followed by SUD, CD, and depressive disorder (DD) (145 [23.7%]), SUD, CD, and neurodevelopmental disorder (NDD) (133 [21.7%]), and DD, CD and NDD (120 [19.6%]).

Discussion The study found high prevalence of comorbidity among the youth patients of the Missouri DYS facilities receiving care through the University of Missouri telemedicine network. The ideal scenario for assessment of any of these disorders in a patient should include substantial consideration in delineating the symptoms and history before eliminating any of them.

Conclusion The comorbid patterns obtained can help in determining treatment regimens for DYS youth that can be effective in reducing recidivism and delinquency.
Microsurgical Reconstruction of the Nose: The Aesthetic Approach to Total Defects
Authors: Pinto Valentina , Antoniazzi Elisa , Contedini Federico , Pignatti Marco , Pizzigallo Angelo , Marchetti Claudio , Cipriani Riccardo
Published: November 2020

Background Reconstruction of complex defects involving nose and close facial units represents an aesthetic and functional challenge. Restoring satisfactory nasal shape, combining aesthetic, nasal function and patent airways is mandatory. In this paper, we describe our approach to total nose defects and we report our 20-year experience in microvascular nose reconstruction.Clinical cases are shown to illustrate different surgical techniques and the evolution of our approach.

Methods Nasal reconstruction procedures were performed on 21 patients between 2000 and 2020 using the radial forearm flap (RFF) or anterolateral thigh (ALT) flap. Reported reconstructions included total/subtotal nasal defects, caused by cancer resections. The key point of our approach is the expanded forehead flap for skin coverage. Reconstruction is completed by cartilage grafts to restore nasal framework and to shape nasal tip. Ancillary procedures were needed in some cases to optimize aesthetic outcomes.

Results Twenty-one patients completed the multistage nasal reconstruction. The RFF flap was used in 56% of the cases (n = 11), while the ALT flap was used in 44% (n = 10) of our case series. No difference has been detected in the number of reconstructive stages required to achieve the final result comparing RFF and ALT reconstruction (3.3 vs. 3.1 reconstructive steps). Ancillary procedures were performed in 7 patients.

Conclusion Microvascular tissue transfer plays a key role in full-thickness nasal defects restoration. Comparing the two groups, both the RFF and ALT are effective and reliable options in lining reconstruction, although with different indications. Expanded forehead flap, combined to free cartilage graft, is our gold standard to provide external skin coverage to rebuild the nasal framework. According to our current approach, accurate preoperative planning, supported by modern technologic tools, multistage reconstruction, and ancillary procedures are useful to accomplish satisfactory functional and aesthetic outcomes.
Bottom-up versus top-down factor investing: an alpha forecasting perspective
Authors: Zurek Martin , Heinrich Lars
Published: November 2020

In a recent discussion about efficient ways to combine multiple firm characteristics into a multifactor portfolio, a distinction was made between the bottom-up and top-down approach. Both approaches integrate characteristics with equal weights and ignore interaction effects from differences in informational content and correlations between the firm characteristics. The authors complement the bottom-up approach for the missing interaction effects by implementing a linear alpha forecasting framework. Bottom-up versus top-down factor investing is typically discussed using the assumption that all characteristics are equally priced, but the pricing impact of different firm characteristics can vary tremendously. The alpha forecasting perspective provides a theoretical motivation for factor investing and helps to compare the bottom-up and top-down approach with regard to the difference of informational content and interaction effects between firm characteristics. Taking into account the difference in informational content between firm characteristics leads to significant performance improvement in factor models with a high concentration of informational content. Equally weighted characteristics result in related performance irrespective of whether the bottom-up or top-down approach is applied.
Historical roots of militarised conservation: the case of Uganda
Authors: Ashaba Ivan
Published: November 2020

This briefing engages the militarised conservation literature. Three factors key to understanding present militarised conservation in Uganda are discussed: colonial legacies, the country’s post-colonial history of war and conflict, and the current militarisation under the Museveni government as exemplified in the military collaboration between the Uganda Wildlife Authority and the Uganda Peoples' Defence Forces. It argues that the debate about militarised conservation in today’s Uganda has to be situated within the widening mandate of the military institution under the Museveni government, which came to power through the military path and then gradually militarised significant sections of society more broadly.
Reactivity of bifurcation angle and electroosmosis flow for hemodynamic flow through aortic bifurcation and stenotic wall with heat transfer
Authors: Mekheimer Kh S , Shahzadi Iqra , Nadeem S , Moawad A M A , Zaher A Z
Published: November 2020

The purpose of current research is to illustrate the existence of stenosis on the walls of the aortic artery which are rigid having Y-shape symmetric bifurcation. The non-Newtonian nature of blood is treated under impacts of the electroosmosis forces. In this analysis, a mathematical model is done by specifying the physical problem. Exact solutions are calculated through Mathematica. Graphical configurations are used to discuss the hemodynamics impacts for the concerned parameters. Also, the wall shear stress is studied on the main artery and artery bifurcated. Among of the most important results that the hemodynamic velocity throughout the parent artery is higher than when it moves in the bifurcation channels (arterioles) , a high value is observed for shear stress at outer wall of the arterioles and a comparatively low value of shear stress is observed at the arterioleâ€™s region.
Distinguishing quantum features in classical propagation
Authors: Titimbo K , Lando G M , de Almeida A M Ozorio
Published: November 2020

The strictly classical propagation of an initial Wigner function, referred to as TWA or LSC-IVR, is considered to provide approximate averages, despite not being a true Wigner function: it does not represent a positive operator. We here show that its symplectic Fourier transform, the truncated chord approximation (TCA), coincides with the full semiclassical approximation to the evolved quantum characteristic function (or chord function) in a narrow neighbourhood of the origin of the dual chord phase space. Surprisingly, this small region accounts for purely quantum features, such as blind spots and local wave function correlations, as well as the expectation of observables with a close classical correspondence. Direct numerical comparison of the TCA with exact quantum results verifies the semiclassical predictions for an initial coherent state evolving under the Kerr Hamiltonian. The resulting clear criterion for any further features, which may be estimated by classical propagation, is that, within the chord representation, they are concentrated near the origin.
Particle microscopy by surface plasmon polariton waves at the interface of dielectric and silver silica nano-composites
Authors: Ullah Sami , Wahid Umer , Bacha Bakht Amin , Ullah Arif , Ullah Zakir
Published: November 2020

The dielectric tensor of four level atomic medium coupled with dielectric function of silver silica nano-composites material to modify dispersion relation of surface plasmon polaritons (SPPs). The rapid damping of SPPs is used to localized atomic particles in two dimension inverse position space. Directions, phases and intensity of the control field play important roles in the localization of atoms in a unit wavelength domain. Ten, six, four and two localization peaks are investigated by SPPs damping in different quadrants. A single broad localized peak symmetric about origin are also investigated. The theoretical work of this article may be useful for quantum information in Plasmonster technology.
TEM study of chronic alcoholism effects on early carcinogenesis by probing the nanoscale structural alterations of cell nuclei
Authors: Adhikari Prakash , Shukla Pradeep K , Ghimire Hemendra M , Hasan Mehedi , Sahay Peeyush , Almabadi Huda , Tripathi Vibha , Skalli Omar , Rao Radhakrishna , Pradhan Prabhakar
Published: November 2020

Nanoscale structural alteration in the nuclei of cells with the progression of carcinogenesis is due to the rearrangements of the basic building blocks in the cell such as DNA, RNA, lipids, etc. Although epigenetic modifications underlie the development of cancer, exposure to carcinogenic chemicals such as alcohol also enhances the development of cancer. We report the effects of chronic alcoholism on early-carcinogenesis based on changes in the degree of nanoscale structural alterations (L
d) in nuclei. For this, transmission electron microscopy (TEM) imaging of the nuclei of colonic cells is performed for the following four mouse models: control mice; chronic alcoholic mice treated with ethanol (i.e., EtOH mice); mice treated with colonic carcinogen azoxymethane (AOM) and dextran sulfate sodium (DSS) that induced colitis (i.e., AOM + DSS mice); and chronic alcoholic or EtOH treated mice, together with AOM and DSS treatment (i.e., AOM + DSS + EtOH mice). The disordered optical lattices are constructed from their respective TEM images of thin colonic cell nuclei and the L
d values are calculated using the inverse participation ratio (IPR) technique from the spatially localized eigenfunctions of these lattices. Results show no significant difference in the average L
d value of the colon cell nuclei of alcohol treated mice relative to its control [i.e., L
d(C) ∼ L
d(EtOH)]; however, an increase in the L
d value of alcohol treated precancerous cells [i.e., L
d(AOM + DSS + EtOH) > L
d(AOM + DSS)], indicating that alcohol accelerates the early carcinogenic process.
Wideband near-zero-index metamaterials created by using a supercell microstructure in the terahertz range
Authors: Luo Tianzi , Jing Xufeng , Gan Haiyong , Li Chenxia , Hong Zhi
Published: November 2020

Zero-index metamaterials are widely used in electromagnetic devices due to their favorable optical properties such as infinite large-phase velocity and quasi-infinite wavelength. However, insufficient bandwidth and high loss seriously limit the wide application of zero refractive index metamaterials (ZIMs), especially in the terahertz band. Here, we propose a kind of supercell microstructure metamaterial to realize a broadband near-zero refractive index. This new superlattice structure contains four subunit structures of different sizes in a single unit. Dual broadband characteristics of the near-zero refractive index can be demonstrated in our design. The bandwidth of the near-zero index can reach about 30 GHz with low loss. The resonance principle of the supercell microstructure and the generation mechanism of the near-zero refractive index are discussed in detail. The influence of the thickness of the medium, of the thickness of the metal sheet, and of the period of the central area and the metal line width on the near-zero refractive index is analyzed. Dual broadband zero-refractive metamaterials bring wider applications to various optoelectronic devices for arbitrary wavefront conversion, directional radiation, and obstacle-free light guiding.
Highly-accurate second-virial-coefficient values for helium from 3.7 K to 273 K determined by dielectric-constant gas thermometry
Authors: Gaiser Christof , Fellmuth Bernd
Published: November 2020

Since the redefinition of the base unit kelvin via fixing the Boltzmann constant in 2019, it has been possible to realise the unit applying different gas-thermometry methods in accordance with the ‘Mise en pratique for the definition of the kelvin in the SI’. For this application, the use of data for the gas properties resulting from ab initio calculations is of special interest because it makes primary thermometry much easier. But since a rigorous estimation of the uncertainty of theoretical calculations is at least very complex, if not impossible, a check of the results by a comparison with highly-accurate experimental values is mandatory. Such a check is performed for the second virial coefficient of helium, which is a widely used measuring gas, in the temperature range from 3.7 K to 273 K. For obtaining highly-accurate second-virial-coefficient values (relative uncertainty at a few tenth of a percent level or even better), isotherms were measured with the PTB dielectric-constant gas thermometer. The highly-accurate isotherm data were evaluated by fitting, applying an extended working equation for the dependence of the gas pressure on the dielectric constant. The comparison with the results of the latest ab initio calculations shows coincidence within the combined uncertainty estimates.
Hepatoprotactive Effect of Lallemantia royleana Seeds Extract Against the Toxicity of Rifadin Through Reduction BAX Expression in Liver Tissue of Albino Mice
Authors: Abdulhussein Mohammad Fahdil , Showait Al-Asady Zainab Thamer
Published: November 2020

This study was aimed to investigate the role of crud alcoholic extract of Lallemantia royleana seeds thruogh reduction the hepatotoxicity of rifadin drug in liver tissue. The animal (40 mice) were divided into four groups the first group treated with normal saline (0.9%) for 28 days as acontrol, the second group treated with rifadin (1.5 mg/kg/day) for 28 days, third group treated with acoholic extract of Lallemantia royleana seeds (1% w/v) for 28 days, while the forth group treated with alcoholic extract of seeds alone for 5 days and with alcoholic extract and rifadin for 28 days, so the total period of this group is 33 days. The liver specimens were collected and processed with immunohistochemical staining kit to detect Bax protein in hepatocytes. The microscopic examination results of liver slides coloured with imununohistochemical staining technique in animal experimental groups showed increased in the number of cells with positive immunoreaction for Bax in animal group treated with rifadin drug comparing with other experimental groups (seeds extract and drug group, seeds extract group, control group)which showed significant decreasing in the number of cells with positive immunoreaction for Bax.
Effect of Adsorption on Electrical Conductivity Values, Ionization Constant and Degree to Di Hydroxy Benzoic acid By Using Natural Surfaces
Authors: Ridha Nuha Abdul-Saheb , Kamal Noor Mustafa , Ridha Maha Abdul-Saheb
Published: November 2020

The effect of the adsorption process on electrical conductivity, equivalent conductivity, ionization constant and dissociation degree was studied to Di hydroxy benzoic acid with different concentrations by using natural surfaces (Hazelnut peel and walnut peel ). The results refers to decrease electrical conductivity after acid adsorption on both surfaces. The effect of acid concentration on the degree of disintegration and the ionization constant was also studied.
Extraction, characterization and bioactivity of chitosan from farms shrimps of Basra province by chemical method
Authors: Al-Hasan Hamdan Israa Abd , Alhnon Farah Jameel , Al-Hasan Hamdan Alaa Abd
Published: November 2020

This paper include the extraction of chitin and transformation it to chitosan from the shrimps shells (waste) that grow up at sea farm in Al-Basra Province, the extraction done according to the literatures by two methods the difference between them was in the first step, but other steps were same methods, the results show sample A was higher than sample B in good yield and other physicochemical properties ( moisture, intrinsic viscosity, daacetylation degree, solubility, and fat binding capacity) which were measured to both samples, chitosan samples were characterization with FT-IR spectrum, in addition the biological activity for chitosan was tested against E.coli, P. asparagi, S. aureus, and B. cerus, the results show that sample A has inhibited these bacteria more than sample B.