bluuebunny/crossref_metadata_2025 huggingface dataset:
Study of Bonding Mechanisms in Cold Spray of Metal-to-Polymer through a Numerical Approach
Authors: Viscusi Antonio , Bruno Matteo , Carrino Luigi , Della Gatta Roberta , Iandolo Giuseppe , Perna Alessia Serena
Published: July 2022

Cold spray (CS) is a low-temperature process that can be used for the metallization of temperature-sensitive materials, such as polymers or polymer matrix composites, so coupling the lightweight of polymers with the wear resistance, physical properties and hardness of metals. The study of the cold spray of metal particles applied to polymers is still in its early stage and the deposition mechanisms underlying the process are not thoroughly understood yet. Moreover, numerical studies of cold spray of metal-to-polymer are almost completely absent in literature. Therefore, aiming to fulfill this gap of knowledge, the scope of this work is to develop a numerical FE model capable of predicting the impact and the adhesion of a micron size metallic particle onto a polymeric substrate. The results from the model were compared with the experimental outcomes found in literature to establish the effectiveness of the model that was used as a powerful tool to better understand the bonding mechanisms and all the related phenomena ruling the CS process of metal-to-polymer.
Uncertainty Quantification in the Directed Energy Deposition Process Using Deep Learning-Based Probabilistic Approach
Authors: Pham Thinh Quy Duc , Hoang Truong Vinh , Tran Xuan Van , Fetni Seifallah , Duchêne Laurent , Tran Hoang Son , Habraken Anne-Marie
Published: July 2022

This study quantifies the effects of uncertainty raised from process parameters, material properties, and boundary conditions in the directed energy deposition (DED) process of M4 High-Speed Steel using deep learning (DL)-based probabilistic approach. A DL-based surrogate model is first constructed using the data obtained from a finite element (FE) model, which was validated against experiment. Then, sources of uncertainty are characterized by the probabilistic method and are propagated by the Monte-Carlo (MC) method. Lastly, the sensitivity analysis (SA) using the variance-based method is performed to identify the parameters inducing the most uncertainty to the melting pool depth. Using the DL-based surrogate model instead of solely FE model significantly reduces the computational time in the MC simulation. The results indicate that all sources of uncertainty contribute to a substantial variation on the final printed product quality. Moreover, we find that the laser power, the convection, the scanning speed, and the thermal conductivity contribute the most uncertainties on the melting pool depth based on the SA results. These findings can be used as insights for the process parameter optimization of the DED process.
Metamaterial Mechanical Performances: A Single Cell Analysis
Authors: Ranzini Giacomo , Giorleo Luca , Ceretti Elisabetta
Published: July 2022

In this research the effect of the geometric features of an auxetic metamaterial structure was investigated by the authors. In particular, a re-entrant honeycomb geometry was selected as case study. Connectors inclination, width and length have been changed to study mechanical behavior and deformation under compression. The procedure adopted was both experimental and numerical. Solutions proposed highlight benefits in terms of compression load and controlled lateral displacement that is possible to achieve.
Fracture Characterization of Advanced High Strength Steel USS CR980XG3 Using Phase-Field Diffusive Approach in Ductile Solids
Authors: Azinpour Erfan , Jimenez Manuel , dos Santos Abel , de Sá J. César
Published: July 2022

In this work, the utilization of a phase-field ductile fracture model in the failure analysis of advanced steels is investigated. The importance of advanced steels is potentially proven, for instance in automotive industry, due to its light weight, which entails the crucial role of fracture analysis in these structures. A third generation advanced high strength USS CR980XG3™️ AHSS material is considered to perform fracture analyses. For this purpose, the necessary data regarding the stress distribution and fracture patterns from digital image correlation tests are utilized for subsequent numerical experimentations.A recent phase-field model of ductile fracture is employed herein for the analysis of crack advance in this class of materials. The significance of the choice of material properties using this model is shown through the analysis of an experimental fracture benchmark called Shear Fracture specimen, through assessment of crack evolution and force diagrams.
Process Stability and Reproducibility of the Dieless Drawing Process for AZ31 Magnesium Wires
Authors: Braatz Merle , Bohlen Jan , Ben Khalifa Noomane
Published: July 2022

Magnesium (Mg)-based wires are in the focus of interest for numerous applications like micro-forming technologies or medical engineering. Manufacturing thin Mg-based wires is widely realized by applying a conventional multiple pass cold wire drawing process. This requires a complex manufacturing schedule of multiple passes with intermediate heat treatments to overcome work hardening, because of the cold forming process. Especially Mg and its alloys are known for their rather low formability at room temperature associated with the hexagonal close-packed lattice structure. The dieless drawing process uses local heating to initialize a localized plastic zone under an external tensile load to achieve higher reductions in diameter in a single wire drawing pass. It can therefore present a solution for a more efficient warm manufacturing process of Mg-based wires. In this study, the stability of the steady state material flow during a dieless wire drawing process and its reproducibility was investigated. For this purpose, a variation of process parameters was selected and wire manufacturing was carried out using magnesium alloy AZ31. A single and double dieless drawing process was applied. Additionally, a conventional cold wire drawing process including a die with the same forming schedule was executed as a benchmark experiment. The results of this study show, that the dieless drawing process is not only a stable process after reaching the steady state, but it is also a reproducible and accurately adjustable process. Moreover, the dieless drawing process maintains the property profile of the starting material to a large extend.
Identification of Anisotropic Yield Functions Using FEMU and an Information-Rich Tensile Specimen
Authors: Zhang Yi , Andrade-Campos António , Coppieters Sam
Published: July 2022

To fully exploit the predictive accuracy of advanced anisotropic yield functions, a large number of classical mechanical tests is required for calibration purposes. The Finite Element Model Updating (FEMU) technique enables to simultaneously extract multiple anisotropic parameters when fed with heterogeneous strain fields obtained from a single information-rich experiment. This inverse approach has the potential to mitigate the experimental calibration effort by resorting to a single, yet more complex experiment augmented with Digital Image Correlation. In this paper, we inversely identify the sought anisotropic parameters of two selected yield functions for a low carbon steel sheet based on the previously designed information-rich tensile specimen. The experimentally acquired strain field data is used to inversely identify the Hill48 yield criterion and the Yld2000-2d yield function, respectively. The results are compared with conventional calibration methods for both anisotropic yield functions. The inverse identification is then thoroughly studied using virtual experiments enabling to disentangle the effect of the material model error and the strain reconstruction error (DIC), respectively. It is shown that the material model error dominates the inverse identification of the Hill48 yield criterion. The reduced material model error for the Yld2000-2d yield function enables obtain inversely identified anisotropic parameters that are closer to the reference parameters. The paper clearly shows the importance of the predictive accuracy of the selected anisotropic yield function when applying inverse identification. Keywords: Anisotropic yield criteria; Material parameters identification; Heterogeneous mechanical tests; Inverse identification; DIC.
Parameter Identification and Modeling of Hardening to Preserve Identical Predictions under Monotonic Loading
Authors: Yang Yan Feng , Vincze Gabriela , Baudouin Cyrille , Chalal Hocine , Balan Tudor
Published: July 2022

Advanced hardening models accurately describe the transient plastic behavior (reyielding, stagnation, resumption...) after various strain-path changes (reverse, orthogonal...). However, a common drawback of these models is that they usually predict monotonic loading with lower accuracy than the regular isotropic hardening models. Consequently, the finite element predictions using these models may sometimes lose in accuracy, in spite of their tremendous theoretical superiority. This drawback has been eliminated in the literature for the Chaboche isotropic-kinematic hardening model. In this work, a generic approach is proposed for advanced hardening models. Arbitrary models could be successfully compensated to preserve rigorously identical predictions under monotonic loading. A physically-based model involving a 4th order tensor and two 2nd order tensors was used for the demonstration. The parameter identification procedure was greatly simplified by rigorously decoupling the identification of isotropic hardening parameters from the other parameters.
Influence of Macro-Structured Tools on the Formability of Aluminum Alloys in the Cryogenic Temperature Range
Authors: Tulke Marc , Wolf Alexander , Lafarge Rémi , Grunow Fabius , Brosius Alexander
Published: July 2022

Aluminum materials are popular materials for research in terms of lightweight construction. How cryogenic forming can be used to increase material utilization in terms of resource efficiency is one of the areas being investigated. Subject of this study are numerical and experimental investigations regarding the formability of the aluminum alloy AA6014-T4 with macro-structured deep drawing tools at cryogenic temperatures. The macro-structure of the deep drawing dies significantly reduces the heat flux between the dies and the blank due to the reduced contact area. For this reason, active cooling or heating of the dies is not required. The process of heat conduction between the tool and the blank, as well as the deep drawing process, is calculated using the FE-method and compared with the experimental investigations. In addition, the induced residual stresses are determined using the hole-drilling method and compared with the computational solution. The presented examination shows an improved deep drawing ratio of the aluminum alloy AA6014-T4 at cryogenic blank temperature without active tool cooling. Additionally, the influence of the blank temperature on the forming regarding the residual stresses in the cups is analyzed and discussed.
Performance Evaluation of Lubricants with Swift Cup Drawing
Authors: Demazel Nathan , Kacem Ahmed , Thuillier Sandrine , Laurent Hervé , Briend Patrick , Masse Jean-Philippe
Published: July 2022

The quality of a part produced using stamping process is dependent on many parameters such as the geometries of the tools and the initial blank, their surface state, the clamping force or contact pressure, the tools velocity and the lubrication. In order to discriminate different lubricants for stamping process in automotive industry under various conditions of clamping force and punch velocity, the Swift cup drawing test is used to evaluate the performance of three lubricants, i.e., two oil-based liquids and one dry film, applied on AA5182-O sheets. Moreover, finite element simulations are used to estimate friction coefficients of these lubricants.
Application of the DIC System to Build a Forming Limit Diagram (FLD) of Multilayer Materials
Authors: Lisiecka-Graca Paulina , Kwiecień Marcin , Madej Łukasz , Majta Janusz , Muszka Krzysztof
Published: July 2022

The extraordinary combination of strength and ductility of multilayered materials makes them attractive in the various applications and industries (military, aerospace, energy industry etc.). In the present work, the investigated materials were joined into multilayered sheet using the explosive welding method. The three-layer material was made of two titanium sheets and one Armco iron sheet in between. Materials produced by explosive welding can easily be used in a simple deformation process, but more complex processes that employ a more complex mechanical state are still not sufficiently studied. The presented study analyzes the possibilities of using Ti - Armco - Ti sheet for the deep drawing process. For this purpose, the forming limit diagram (FLD) has been constructed and verified. FLD is one of the most important tools in the analysis of sheet metal forming processes. In the presented work the non-standard method (Erichsen test) coupled with Digital Image Correlation analysis was used. The obtained results confirmed that the method of producing the tested sheet and the morphology of the microstructure created have a direct impact on the deformation mechanisms.
Experimental Investigation of Efficiency and Deposit Process Temperature during Multi-Layer Friction Surfacing
Authors: Kallien Zina , Roos Arne , Klusemann Benjamin
Published: July 2022

Multi-layer friction surfacing (MLFS) follows the principle of the friction surfacing (FS) process, which is an established solid state coating technology for similar and dissimilar metallic materials. With this approach, the deposition of a consumable material on a substrate is enabled via friction and severe plastic deformation (SPD), processing the material below its melting temperature. The focus of the present study lies on the investigation of the temperature distribution during MLFS deposition. The measurements show that the temperature within the stack tends to be slightly higher on the advancing side. Additionally, the deposition behavior, i.e. deposition rate and consumable stud consumption rate, was investigated. Along MLFS stack height, deposition efficiency tends to sightly decrease, shown by decreasing layer thickness and increased length of remaining consumable studs. Overall, MLFS is highly repeatable for multiple layers and presents stable deposition conditions. Additionally, the technique has a comparatively low heat input to the substrate and the already deposited material.
Hybrid Forming - A Method for Simultaneous Forming of High Strength Metal Sheet and Long Fiber Reinforced Plastic
Authors: Fang Xiang Fan , Kloska Tobias , Heidrich Daniel
Published: July 2022

Fiber reinforced plastics (FRPs) are increasingly being used to reinforce the steel or aluminum automotive structure components. Currently, these multi-material applications are realized in general by a multi-stage manufacturing with considerable cost increase. To avoid this, a new hybrid forming method has been proposed and developed. It uses the half liquid FRP as a pressure media to hydro-form the sheet metals, form the reinforcement ribs of FRPs, and create the bonding between metal sheet and FRP in the same time and process step. In this work, the die sealing concepts for two test geometries could be successfully developed. The hybrid forming parameters (Temperature, pressure, speed etc.) are in a reasonable range and can be accepted by the industry. It could be approved that high strength steels with up to 800 MPa tensile strength could be hybrid formed successfully together with a LFT PA6 GF40 for a real car component. 20% weight reduction could be achieved.
Fracture Prediction of Third Generation Advanced High Strength Steels Using Hosford-Coulomb Damage Model
Authors: Jimenez Manuel , dos Santos Abel , Amaral Rui , Cruz Daniel J. , de Sá J. César
Published: July 2022

The latest demands in reduction of emissions compel the automobile industry to lighten the structure of vehicles using third generation advanced high strength steels. Due to the novelty of these steels, there is a need to characterize its fracture behavior during the forming process. This paper presents a study of strain field, crack locus and instant of failure for 980 grade third generation advanced high strength steel using defined tests with two specimens. Numerical simulations and experiments have been performed to evaluate and to compare the obtained results for this steel. Numerical simulations with implemented Hosford-Coulomb damage model use the extended finite element method to predict the fracture occurrence. According to results, numerical simulation predicts crack locus similar to experimental tests. Failure of the material shows a high sensitivity to damage evolution law.
Failure Prediction of Automotive Components Utilizing a Path Independent Forming Limit Criterion
Authors: Barlo Alexander , Sigvant Mats , Manopulo Niko , Islam Md. Shafiqul , Pilthammar Johan
Published: July 2022

An area in the automotive industry that receives a lot of attention today is the introduction of lighter and more advanced material grades in order to reduce carbon emissions, both during production and through reduced fuel consumption. As the complexity of the introduced materials and component geometries increases, so does the need for more complex failure prediction approaches. A proposed path-independent failure criterion, based on a transformation of the limit curve into an alternative evaluation space, is investigated. Initially, the yield criterion used for this transformation of the limit curve was investigated. Here it was determined that the criterion for the transformation could not be decoupled from the material model used for the simulation. Subsequently, the approach using the transformed limit curve was tested on an industrial case from Volvo Cars, but a successful failure prediction was not obtained.
Laser-Powder Bed Fusion of Inconel 718 Alloy: Effect of the Contour Strategy on Surface Quality and Sub-Surface Density
Authors: El Hassanin Andrea , Napolitano Francesco , Trimarco Carmela , Manco Emanuele , Scherillo Fabio , Borrelli Domenico , Caraviello Antonio , Squillace Antonio , Astarita Antonello
Published: July 2022

The in-situ contour strategy during Laser-Powder Bed Fusion (L-PBF) process remains one of the most promising solutions to improve the poor surface quality of the parts. On the other hand, it is well established that contour step affects the formation of sub-surface defects. The aim of this work is to assess the entity of sub-surface defects during the Laser-Powder Bed Fusion of Inconel 718 samples for which different contour processing conditions are considered. Cubic samples with 10 mm side were produced through L-PBF using a Concept Laser Cusing M2 L-PBF machine. The samples were printed with fixed bulk laser parameters, adopting a layer thickness of 30 μm and a chessboard laser scanning strategy. The in-situ contour conditions were changed in terms of laser scanning speed and hatch zone border. Afterwards, the samples were analyzed in terms of surface roughness (Sa) and sub-surface density through confocal microscopy. The results revealed that the surface roughness was the most affected output as a function of the varied process parameters, including the sample position on the building platform, with values ranging from 13 to 32 μm. On the other hand, the sub-surface density was always higher than 99%.
Thermal Modeling of Laser Powder Bed Fusion during Printing on Temperature-Unstable Materials Considering Local Sintering
Authors: Frölich Felix , Kärger Luise
Published: July 2022

The integration of local metal structures into polymer components using Laser Powder Bed Fusion (PBF-LB/M) offers great potential regarding multifunctional lightweight structures. However, such process hybridization involves huge challenges. In order to reduce the temperature input into the less temperature-resistant materials, the use of lower laser powers in the interfacial region is essential. The resulting local sintering of the metal powder affects the thermal properties in the interfacial region, leading to a change in heat dissipation in the temperature-unstable material. A modeling approach oriented to selective laser sintering is presented for predicting the degree of sintering and associated thermal properties in the context of PBF-LB/M process simulation.
Material Flow Visualization for Metal Extrusion on near Industrial Scale
Authors: Horwatitsch Dieter , Herr Johanna , Hinterer Andreas
Published: July 2022

In the simulation of bulk forming processes the validation of the applied simulation models is necessary. Then, predictive simulations are possible. A visualisation method is an advanced way to create additional evaluation parameters. In this work, the upscaling of a newly developed non-destructive method from semi-industrial to near-industrial scale for metal extrusion of aluminium alloys is presented. A copper coating, which deforms with the billet material, was applied to one half (in the longitudinal direction) of a cast billet and detected by computed tomography (CT). The copper pattern was applied by a plasma coating technology to determine the deformation of the billet material during the process until the final profile. A detailed analysis of the upscaled method with improved geometric setup shows the superiority of the newly chosen properties enabling a complete determination of strain state also in the profile.
Characterization and Modelling of Sheet Material with Graded Strength for more Accurate Finite Element Analysis
Authors: Lenzen Matthias , Kraus Martin , Merklein Marion
Published: July 2022

Many sheet materials do not exhibit constant properties over the sheet thickness. On the one hand, this can be caused by a rolling process with a pass reduction of 1-2%, the so-called skin pass rolling. This is mainly used for deep drawing steel grades to eliminate the pronounced yield strength of the base material. Another possibility is abrasive blasting or shot peening of sheet metal. This causes plastic deformation of the sheet surface and material strengthening. The grading can be used to locally strengthen components or locally adapt the roughness. Since many production processes today are designed numerically, the mapping of such a grading is necessary but currently not implemented in FE code. Aim of this research is, to correlate the material hardness to a plastic pre-strain with a newly developed characterization method. For this purpose, graded material properties are generated by means of abrasive blasting as an example process. The resulitng locally varying work hardening over the sheet thickness is further integrated in finite element analysis by the assignment of a starting condition of a 2d-shell element formulation. With this approach, it is possible to map the graded material properties easily in FE simulations with a very good accuracy.
FE Crash Modeling of Aluminum-FRP Hybrid Components Manufactured by a Hybrid Forming Process
Authors: Jayakumar Saarvesh , Stolz Lorenz , Anand Sharath , Hajdarevic Amir , Fang Xiang Fan
Published: July 2022

Through the patented process of hybrid forming [1], it is possible to produce a bonded metal-plastic-hybrid component in one process step with the help of an edge-sealed pressing tool. Such a component exhibits an enormous energy absorption potential. To use this complete potential, a reliable FE-Modelling is necessary, that can exactly replicate the complex material layup consisting of an isotropic metal, a very thin bonding layer, and an anisotropic glass mat reinforced thermoplastic (GMT) for crash load case. A methodology is proposed to numerically predict the behavior of the metal GMT aluminum components. And finally, the experimental results of Hybrid components are validated for three-point bending and axial crash load cases.
Design of Single Point Incremental Forming for a Motorcycle Headlight Fairing Manufacture
Authors: Wiessler Oscar , Long Hui
Published: July 2022

This paper presents a study of design of a motorcycle headlight fairing for single point incremental forming by employing a simplified design guideline in conjunction with a finite element simulation of the forming process. Comparison with the experimental formed motorcycle headlight fairing is performed based on a detailed analysis of geometric accuracy of the formed parts. The study may serve as a demonstration of capabilities of single point incremental forming with respect to dimensional accuracy when forming complex parts.
Material Parameter Identification of Elastoplastic Constitutive Models Using Machine Learning Approaches
Authors: Bastos Nelson , Prates Pedro André , Andrade-Campos António
Published: July 2022

Today, the vast majority of design tasks are based on simulation tools. However, the success of the simulation depends on the accurate identification of the constitutive parameters of materials, i.e., its calibration. The classical parameter identification strategy, which relies on homogeneous tests, does not provide accurate and robust results required by the automotive and aerospace industry. Recently, numerical inverse methods, such as the Finite Element Model Updating (FEMU) and the Virtual Fields Method (VFM), have been developed for identifying constitutive parameters based on heterogeneous tests. Although these methods have proven effective for linear and non-linear models, the parameter identification process is complex, making it computationally expensive. In this work, a machine learning algorithm (XGBoost) is used to pursue the goal of parameter identification of non-linear models using heterogeneous tests. A statistical analysis is conducted to identify the correlation between the training dataset size, mechanical tests results and the material parameters. The goal is to understand the importance of the different inputs and to reduce the computational time.
Piecing Complement Together with LEGO Bricks: Impacts on Interest, Confidence, and Learning in the Immunology Classroom
Authors: Bohlson Suzanne S , Baty Joshua J , Greenlee-Wacker Mallary C , Bruns Heather A
Published: July 2022

Teaching and learning complex molecular cascades can often be challenging. In immunology, students struggle to visualize immunological processes, such as activation of the complement system, which involves three separate cascades leading to multiple effector functions. Offering learning activities that use tangible modeling can help students learn conceptually difficult content by fostering a visual understanding of concepts, as well as instill confidence and interest in the material. In this article, we describe a learning activity using LEGO bricks that demonstrates the activation of the classical, lectin, and alternative complement pathways and formation of the membrane attack complex. In both an introductory and advanced immunology course, we investigated the effect of the activity on student learning and subject confidence. Performance on examination questions about complement demonstrated that the LEGO activity improved learning in a naive student population (students in introductory immunology), but not in a previously informed student population (students in advanced immunology). In addition, self-reported confidence in the content was significantly higher in students who completed the LEGO activity in the advanced course, but not the introductory course, compared with those who did not do the activity. Students in both courses who did the activity had a positive perception of the activity, with a majority of students reporting that they enjoyed the activity and had more interest in the complement system.
Aplicativo Investsus: Uma Abordagem Qualitativa sobre Mobile Government
Authors: Reis Mauro Célio Araújo dos , Carneiro Dayse Karenine de Oliveira , Cireno Maria Eugênia Diniz Figueiredo , Júnior Dárcio Guedes
Published: July 2022

O desenvolvimento das tecnologias móveis tem contribuído para a transformação da maneira como os governos entregam seus serviços e, como consequência, o governo móvel ou mobile government impacta a forma como os cidadãos se relacionam com os serviços públicos. Dentro desta perspectiva, este artigo propõe, por meio de uma abordagem qualitativa multi-método, identificar e analisar aspectos de mobile government no desenvolvimento e implantação do aplicativo InvestSUS, no contexto do Ministério da Saúde brasileiro. Com isso, vislumbra-se contribuir com o campo de pesquisa sobre mobile government em países em desenvolvimento. Para tanto, foi realizada uma triangulação de técnicas qualitativas na coleta e análise de dados, que resultou na construção de um framework para análise da implementação de ferramentas de mobile government no setor público. Foram identificadas 19 variáveis relacionadas ao framework proposto, bem como 5 novas variáveis, tais como: transparência da informação pública, controle social, usabilidade, equipe multidisciplinar e facilidade de acesso. Os resultados deste estudo, portanto, refletem uma oportunidade para compreensão do fenômeno de mobile government no contexto do setor de saúde pública.

Investsus App: A Qualitative Approach to Mobile Government

The development of mobile technologies has contributed to the transformation of the way governments deliver their services and, as a consequence, mobile government impacts the way citizens relate to public services. In this sense, we propose, through a qualitative multi-method approach, to identify and analyze aspects of mobile government in the development and implementation of the InvestSUS application, in the context of the Brazilian Ministry of Health. In doing so, it aims to contribute to the field of research on mobile government in developing countries. To this end, a triangulation of qualitative techniques was carried out in data collection and analysis, which resulted in the construction of a framework for analyzing the implementation of mobile government tools in the public sector. We identified 19 variables related to the proposed framework, as well as 5 new variables, such as: transparency of public information, social control, usability, multidisciplinary team, and ease of access. The results of this study, therefore, reflect an opportunity to understand the phenomenon of mobile government in the context of the public health sector.
ГЕНЕЗИС ПОНЯТИЙ «КОМПЕТЕНЦИЯ» И
«КОМПЕТЕНТНОСТЬ» В РОССИЙСКОМ
ОБРАЗОВАНИИ
Authors: Ахмедова Э.И. , Клещицкая К.А.
Published: July 2022

Данная статья содержит термины «компетенция» и «компетентность»,

характеризующие компетентностный подход в современном образовании, процесс его

формирования и актуальность этого подхода в сравнении с традиционным.
АНАЛИЗ ОСНОВНЫХ ПРЕИМУЩЕСТВ И НЕДОСТАТКОВ
КОНТЕЙНЕРНЫХ ПЕРЕВОЗОК
Authors: Рыбинцева М.Д
Published: July 2022

В статье проведен анализ современного состояния и основных преимуществ и

недостатков контейнерных перевозок, определены перспективы их развития. Актуальность

темы обусловлена общемировым ростом контейнерных перевозок грузов на магистральных

видах транспорта, необходимостью поиска новых эффективных транспортнотехнологических систем транспортировки грузов. Теоретической базой исследования

являются научные труды М.В. Шилимова и Е.В. Смоляниновой, информация была

использована из статистических сборников, также использовался материал из интернетисточников.
Graciela S. Alarcón, mentora na esfera acadêmica e na vida familiar
Authors: Fajardo Estefania
Published: July 2022

A Dra. Graciela Alarcón conseguiu realizar com sucesso tanto o seu trabalho acadêmico quanto as suas responsabilidades familiares. Entre as suas muitas realizações no campo da reumatologia, sua pesquisa sobre o lúpus, particularmente em populações hispânicas, tem alcançado um reconhecimento global. Nesta entrevista ela lembra de acontecimentos da sua vida, do seu percurso profissional e académico, da sua paixão pela reumatologia e do que significa hoje apoiar as novas gerações.
Association of Postural Sway with Kellengren Lawrence Grade II and III of Osteoarthritis of Knee Joint among Elderly Population.
Authors: Agrawal Sheetal , Shewale Dr. Sonyabapu , Ganvir Dr. Shyam
Published: July 2022

Background: Postural sway is very common in elderly population. It is mainly associated with balance. There are two factors, Decreased proprioception –which leads to sway when walking and increased reliance on vision. Vestibular weakness – as the person ages it’s common to have vestibular deficits which affects gaze stability and ability to turn head which affects balance. This may cause fall and increase the risk of injury.
Objective: 1. To investigate the postural sway in elderly OA knee patients.

To investigate the postural sway according to different grades of OA.

Methodology: It was a cross-sectional study. Total 60 elderly individuals with OA knee were included using simple random sampling method.
Result: The data was collected in OA Knee patients for sway in all four directions was analyzed with eyes open and eyes closed conditions. All 60 subjects having more sway in anterior and left lateral direction with both eyes open and eyes closed condition compared to their sway in posterior and right lateral direction.
Conclusion: This study concludes that more sway was observed in anterior and left lateral direction both with eyes opened and eyes closed compared to posterior and right lateral direction in all Grade I, Grade II ,Grade III patients, all males and females, young old and middle old subjects. While in old old subjects the sway was found more in anterior and right lateral direction compared to posterior and left lateral direction.
Book Review
Authors: Chilkapurawar Ruchita Rao , Diwate Dr. Abhijit D
Published: July 2022

This is the reworked 21st edition of the book PJ Mehta with many improvements particularly in terms of clarity. As the title of the book and its individual chapters suggest the practical point of view of different systems of the body which are updated as per the latest guidelines. This edition is accompanied by various visual aids to help students and practitioner to understand the subject of medicine better. Each chapter contains clinical applications which highlight the relevance of the text and concludes with a brief but relevant list of references.
Diffuse Alopecia Areata and Its Trichoscopic Findings Following COVID-19 mRNA-1273 Vaccination: A Case Report
Authors: Chen Hsuan-Hsiang
Published: July 2022

Background: Alopecia Areata (AA) is a common autoimmune disease leading to non-scarring hair loss. Previously, AA had been noted following various vaccinations including influenza virus, hepatitis B virus, herpes zoster virus, human papillomavirus, Japanese encephalitis, and Clostridium tetani. During this pandemic, AA following SARS-CoV-2 vaccine injection was rarely reported

Objective: We report a case of diffuse AA and its trichoscopic findings following COVID-19 mRNA-1273 vaccination.

Method: A trichoscopic examination of the scalp was performed. An English literature review through PubMed and an online search of the Vaccine Adverse Event Reporting System (VAERS) database were conducted.

Finding: Only 20 patients of AA following SARS-CoV-2 vaccination were reported in the English literature. Black dots and broken hair were the most common features, followed by yellow dots and exclamation mark hairs. The VAERS database showed 77.8% were associated with the BNT162b2 vaccine and 20.9% with the COVID-19 mRNA-1273 vaccine, respectively.

Conclusion: A rare case of AA and its trichoscopic findings following COVID-19 mRNA-1273 vaccine injection was reported. The COVID-19 vaccines may play a role in various immune-related dermatologic conditions.
Degree of satisfaction of the workers of a road signaling company in the southeast of Mexico
Authors: Cortés Roger Manuel Patrón , García Román Alberto Quijano , Blum Fernando Medina , Chuc Giselle Guillermo , Canul Carlos Alberto Pérez , Chiquni Charlotte Monserrat Llanes
Published: July 2022

Las empresas de señalizaciones viales cada día son más importantes en México, debido al incremento en las vías de comunicación, lo que trae como consecuencia la instalación de más señalamientos y dispositivos de seguridad vial. El objetivo de este estudio es evaluar el nivel de satisfacción de los trabajadores de una empresa de señalización vial, con la finalidad de tomar decisiones para la mejora del comportamiento del persoal. Primero se realizó una medición cuantitativa y luego se reforzaron los resultados mediante entrevistas cualitativas. Los resultados indican que los empleados se encuentran satisfechos. No obstante, existen dimensiones que afectan a los trabajadores tales como la reducida variedad de las actividades, la forma en que se aplican las políticas de la empresa,  y la falta de desarrollo. Por lo que se sugiere buscar alternativas para ofrecer un trabajo más significativo y justo para los empleados.
Singapore Cancer Network (SCAN) Guidelines for Systemic Therapy of Colorectal Cancer
Authors:   The Singapore Cancer Network (SCAN) Colorectal Cancer Systemic Therapy Workgroup
Published: July 2022

Introduction: The SCAN colorectal cancer systemic therapy workgroup aimed to develop Singapore Cancer Network (SCAN) clinical practice guidelines for systemic therapy for colorectal cancer in Singapore. Materials and Methods: The workgroup utilised a modified ADAPTE process to calibrate high quality international evidence-based clinical practice guidelines to our local setting. Results: Five international guidelines were evaluated—those developed by the National Comprehensive Cancer Network for colon (2014) and rectal (2014) cancer, the European Society of Medical Oncology for advanced (2012) and early (2013) cancer and the National Institute of Clinical Excellence (2011). Recommendations on systemic therapy in colorectal cancer were produced. Conclusion: These adapted guidelines form the SCAN Guidelines 2015 for systemic therapy of colorectal cancer.

Key words: Treatment recommendations, Multidisciplinary, Malignancy
Singapore Cancer Network (SCAN) Guidelines for the Initial Evaluation, Diagnosis and Management of Retroperitoneal Soft Tissue Sarcoma
Authors:   The Singapore Cancer Network (SCAN) Sarcoma Workgroup
Published: July 2022

Introduction: The SCAN sarcoma workgroup aimed to develop Singapore Cancer Network (SCAN) clinical practice guidelines for the initial evaluation, diagnosis and management of patients with retroperitoneal soft tissue sarcoma. Materials and Methods: The workgroup utilised a consensus approach to create high quality evidence-based clinical practice guidelines suited for our local setting. Results: Various international guidelines from the fields of radiology, pathology, surgical, medical and radiation oncology were reviewed. Recommendations on the role of radiological imaging, pathology, surgery, radiotherapy and systemic therapy in the management of retroperitoneal soft tissue sarcoma were developed. Conclusion: These guidelines form the SCAN Guidelines 2015 for the diagnosis, staging and optimal management of patients with retroperitoneal soft tissue sarcoma.

Key words: Asian patients, Retroperitonuem, Sarcoma, STS, Treatment
Functional Outcomes of the Second Surgery Are Similar to the First in Asians Undergoing Staged-Bilateral Total Knee Arthroplasty
Authors: Kumar Vijay , Bin Abd Razak Hamid Rahmatullah , Chong Hwei Chi , Tan Andrew HC
Published: July 2022

Introduction: Patients suffering from bilateral knee osteoarthritis often require bilateral total knee arthroplasty (TKA) to alleviate symptoms. There is controversy surrounding the approach to the surgical treatment of such patients. We asked if Asian patients undergoing staged-bilateral TKA had any difference in their short-term functional outcomes, comparing the first TKA to the second one and if the interval between the 2 surgeries had any impact of functional outcomes. Materials and Methods: We identified 100 patients from a single surgeon from 2006 to 2010 who had staged-bilateral TKA and had at least 2 years of follow-up for each TKA. The time interval between the first and second TKA ranged from 6 months to 1 year. Range of motion, Oxford knee questionnaire scores, knee scores and function scores at 6 months and 2 years of follow-up were then compared between the first and second TKA using the Student’s T-test. Results: Although length of stay was reduced and time to ambulation was shorter for the second TKA, there were no significant differences in functional outcomes at 2 years. There was also no difference in outcome when patients were stratified according to time interval between TKAs. Conclusion: Staged-bilateral TKA continues to be a good option for patients presenting with severe bilateral knee osteoarthritis. The second arthroplasty has similar functional outcomes as the first arthroplasty. Our results can be used in preoperative counselling of patients undergoing staged-bilateral TKA.

Key words: Counselling, Orthopaedic surgery, Osteoarthritis
Causative Pathogens of Febrile Neutropaenia in Children Treated for Acute Lymphoblastic Leukaemia
Authors: Lam Joyce CM , Chai Jie Yang , Wong Yi Ling , Tan Natalie WH , Ha Christina TT , Chan Mei Yoke , Tan Ah Moy
Published: July 2022

Introduction: Treatment of acute lymphoblastic leukaemia (ALL) using intensive chemotherapy has resulted in high cure rates but also substantial morbidity. Infective complications represent a significant proportion of treatment-related toxicity. The objective of this study was to describe the microbiological aetiology and clinical outcome of episodes of chemotherapy-induced febrile neutropaenia in a cohort of children treated for ALL at our institution. Materials and Methods: Patients with ALL were treated with either the HKSGALL93 or the Malaysia-Singapore (Ma-Spore) 2003 chemotherapy protocols. The records of 197 patients who completed the intensive phase of treatment, defined as the period of treatment from induction, central nervous system (CNS)-directed therapy to reinduction from June 2000 to January 2010 were retrospectively reviewed. Results: There were a total of 587 episodes of febrile neutropaenia in 197 patients, translating to an overall rate of 2.98 episodes per patient. A causative pathogen was isolated in 22.7% of episodes. An equal proportion of Gram-positive bacteria (36.4%) and Gram-negative bacteria (36.4%) were most frequently isolated followed by viral pathogens (17.4%), fungal pathogens (8.4%) and other bacteria (1.2%). Fungal organisms accounted for a higher proportion of clinically severe episodes of febrile neutropaenia requiring admission to the high-dependency or intensive care unit (23.1%). The overall mortality rate from all episodes was 1.5%. Conclusion: Febrile neutropaenia continues to be of concern in ALL patients undergoing intensive chemotherapy. The majority of episodes will not have an identifiable causative organism. Gram-positive bacteria and Gram-negative bacteria were the most common causative pathogens identified. With appropriate antimicrobial therapy and supportive management, the overall risk of mortality from febrile neutropaenia is extremely low. Key words: Infective complications, Bacterial infections, Mortality, Toxicity
Academic Medicine Education Institute (AM∙EI): Transforming the Educational Culture of Health Professionals
Authors: Goh Sok Hong , Tan Kok Hian , Kamei Robert K , Koo Wen Hsin , Cook Sandy
Published: July 2022

Introduction: The Academic Medicine Education Institute (AM∙EI), jointly established by Duke-NUS Graduate Medical School (Duke-NUS) and Singapore Healthcare Services (SingHealth), is a newly formed health professions education academy designed to cultivate best education practices and create a community of health professions educators. To achieve the aims of AM∙EI, the needs of SingHealth educators have to be understood. Therefore, this study was carried out to assess educators’ perceptions towards the current education climate and their academic needs. Materials and Methods: A 28-item questionnaire consisting of free-response, Likert-type and ranking questions was developed. The questionnaire was electronically distributed to 200 medical and nursing educators, and made available to attendees of the 2012 Singhealth Duke-NUS Scientific Congress through hardcopies. Results: A total of 150 completed questionnaires were received (94 from electronic survey and 56 from Congress). Five themes emerged from the analysis of responses to free-response questions: 1) faculty development, 2) development of a community of educators, 3) recognition for educational efforts, 4) institutional support, and 5) better communication about SingHealth educational activities. Respondents were in highest agreement with the statements (rating of 3.7 out of 5): “The SingHealth education programmes are high quality”, “New learning or teaching methods are welcomed in this institution/hospital”, and “An academic appointment is important to me”. The competencies that respondents felt to be the most important were facilitating discussions, presentation skills, and providing feedback (respective means = 5.1, 5, 5 of 7). Conclusion: This needs assessment provided us with important insights regarding SingHealth medical educators’ perceptions of their education environment and established key priorities for the AM∙EI’s programming efforts. Key words: Academy, Duke-NUS, Singapore, SingHealth
Fasting during Ramadan and Associated Changes in Glycaemia, Caloric Intake and Body Composition with Gender Differences in Singapore
Authors: Yeoh Ester CK , Zainudin Sueziani Binte , Loh Win Nie , Chua Chin Lian , Fun Sharon , Subramaniam Tavintharan , Sum Chee Fang , Lim Su Chi
Published: July 2022

Introduction: Millions of Muslim patients with diabetes mellitus (DM) fast during Ramadan. However, little is known about the metabolic impact of Ramadan fasting. We aimed to study the changes in body composition and metabolic profile in this group of patients. Materials and Methods: We studied 29 Southeast Asian Muslim patients with type 2 diabetes; all underwent pre-Ramadan education. Study variables were weight change, body composition (using multifrequency bioimpedance method, InBody S20®, Biospace, South Korea), blood pressure (BP), glycated haemoglobin (HbA1c), fasting lipid profile, and caloric intake assessment using FoodWorks® nutrient analysis software. Results: Twenty-three subjects fasted ≥15 days; mean ± SD: 57 ± 11 years; 52% were males. HbA1c improved significantly (8.6 ± 2.4% pre-Ramadan vs 8.0 ± 2.3% end-Ramadan, P= 0.017). Despite similar body weight, there was reduction in body fat mass (BFM) (30.9 ± 11 kg vs 29.2 ± 12.2 kg, P = 0.013). Multivariate analysis suggested that the reduction in HbA1c was attributed by reduction in BFM (β = -0.196, P = 0.034). There was no change in visceral adiposity (visceral fat area (VFA)) but stratification by gender showed a reduction amongst females (137.6 ± 24.5 cm2 to 132.5 ± 25.7 cm2, P = 0.017). These changes occurred despite similar total caloric intake (1473.9 ± 565.4 kcal vs 1473.1 ± 460.4 kcal, P = 0.995), and proportion of carbohydrate (55.4 ± 6.3% vs 53.3 ± 7.5%, P = 0.25) and protein intake (17.6 ± 4.1% vs 17.3 ± 5.4%, P = 0.792), before and during Ramadan respectively, but with increased proportion of fat intake (11.9 ± 2.4% vs 13 ± 11.7%, P = 0.04). Seven out of 23 patients had medications adjusted to avert symptomatic hypoglycaemia but none of the patients developed severe hypoglycaemia. Conclusion: Ramadan fasting can be practiced safely with prior patient education and medication adjustment. It also confers modest benefits on metabolic profile and body composition, especially among females.

Key words: Diabetes, Education, Muslims