5,206 research outputs found
Provenance of Leon Idzykovsky’s book collection as a source of historical and bibliological research
Висвітлено значення провенієнцій як історичного джерела в реконструкції
бібліотечних фондів історичних бібліотек. Охарактеризовано різновиди провенієнцій, які розкривають шляхи формування та організацію книгозбірні Леона Ідзіковського та є важливим джерелом при виявленні та реконструкції цього книжкового зібрання.The article deals with provenance as a source of historical and bibliological research.
Compiled has been the list of provenance on the books from Leon Idzykovsky’s books
collection. The author studies the role of provenance in the reconstruction of library
collections
Design and Characterization of a Low-Cost and Efficient Torsional Spring for ES-RSEA
The design of torsional springs for series elastic actuators (SEAs) is challenging, especially when balancing good stiffness characteristics and efficient torque robustness. This study focuses on the design of a lightweight, low-cost, and compact torsional spring for use in the energy storage-rotary series elastic actuator (ES-RSEA) of a lumbar support exoskeleton. The exoskeleton is used as an assistive device to prevent lower back injuries. The torsion spring was designed following design for manufacturability (DFM) principles, focusing on minimal space and weight. The design process involved determining the potential topology and optimizing the selected topology parameters through the finite element method (FEM) to reduce equivalent stress. The prototype was made using a waterjet cutting process with a low-cost material (AISI-4140-alloy) and tested using a custom-made test rig. The results showed that the torsion spring had a linear torque-displacement relationship with 99% linearity, and the deviation between FEM simulation and experimental measurements was less than 2%. The torsion spring has a maximum torque capacity of 45.7 Nm and a 440 Nm/rad stiffness. The proposed torsion spring is a promising option for lumbar support exoskeletons and similar applications requiring low stiffness, low weight-to-torque ratio, and cost-effectiveness
Modified Surface Relief Layer Created by Holographic Lithography: Application to Selective Sodium and Potassium Sensing
Point-of-care diagnostics will rely upon the development of low-cost, noncomplex, and easily integrated systems in order to examine biological samples such as blood and urine obtained from the patient. The development of metal ion sensors is a subject of significant relevance for physiological samples. The level of different blood electrolytes, mainly H+, Na+, K+ and Cl− is considerably used to monitor irregular physiologies. The particular challenge in biosensing, and in fact for any other sensor, is signal differentiation between non-specifically bound material and the specific detecting of the target molecule/ion. The biosensors described in this paper are fabricated by a holographic recording of surface relief structures in a photopolymer material. The surface structures are modified by coating with either dibenzo-18-crown-6 (DC) or tetraethyl 4-tert-butylcalix[4]arene (TBC), which are embedded in a polymer matrix. Interrogation of these structures by light allows indirect measurement of the concentration of the analyte. The influence of polymer matrices with different porosities, plasticised polyvinyl chloride (PVC) and a sol-gel matrix, on the performance of the sensors for detection of K+ and Na+ is examined. Here we demonstrate a proof of concept that by using a matrix with higher porosity one can increase the sensitivity of the sensor. The results showed that the DC sensing layer provides a selective response to K+ over Na+ and the TBC modified grating is more responsive to Na+ over K+. The sensor responds to K+ and Na+ within the physiological concentration range
Exploring experiences and impact of the COVID-19 pandemic on young racially minoritised people in the United Kingdom: A Qualitative Study
Within high-income-countries, the COVID-19 pandemic has disproportionately impacted people from racially minoritised backgrounds. There has been significant research interrogating the disparate impact of the virus, and recently, interest in the long-term implications of the global crisis on young people’s mental health and wellbeing. However, less work explores the experiences of young people from racialised backgrounds as they navigate the pandemic, and the specific consequences this has for their mental health. Forty young people (age 16-25) from black, mixed and other minority backgrounds and living in London, participated in consecutive focus group discussions over a two-month period, to explore the impact of the pandemic on their lives and emotional wellbeing. Thematic analysis identified seven categories describing the impact of the pandemic, indicating: deepening of existing socioeconomic and emotional challenges; efforts to navigate racism and difference within the response; and survival strategies drawing on communal and individual resources. Young people also articulated visions for a future public health response which addressed gaps in current strategies. Findings point to the need to contextualise public health responses to the pandemic in line with the lived experiences of racialised young people. We specifically note the importance of long-term culturally and socio-politically relevant support interventions. Implications for policy and practice are discusse
An Ensemble of Optimal Trees for Classification and Regression (OTE)
Predictive performance of a random forest ensemble is highly associated with the strength of individual trees and their diversity. Ensemble of a small number of accurate and diverse trees, if prediction accuracy is not compromised, will also reduce computational burden. We investigate the idea of integrating trees that are accurate and diverse. For this purpose, we utilize out-of-bag observation as validation sample from the training bootstrap samples to choose the best trees based on their individual performance and then assess these trees for diversity using Brier score. Starting from the first best tree, a tree is selected for the final ensemble if its addition to the forest reduces error of the trees that have already been added. A total of 35 bench mark problems on classification and regression are used to assess the performance of the proposed method and compare it with kNN, tree, random forest, node harvest and support vector machine. We compute unexplained variances and classification error rates for all the methods on the corresponding data sets. Our experiments reveal that the size of the ensemble is reduced significantly and better results are obtained in most of the cases. For further verification, a simulation study is also given where four tree style scenarios are considered to generate data sets with several structures
Effect of corrosion on mechanical properties of the joining of materials
The effect of corrosion behavior in critical environmental conditions on the mechanical properties of composite/metal materials joints was investigated by immersing metalic materials into 5wt% hydrochloric acid solutions. The current study was carried out on a single lab joint with a total thickness of 4mm; thus, a destructive test was undertaken to investigate the corrosion behavior induced degradation of mechanical properties followed by Scanning electron microscope analysis (SEM). The joined specimens were examined under both non-corrosive and corrosive environmental conditions. Moreover, the Taguchi analysis of experimental data for maximizing the required output is carried out to validate the impact and significance of input factors. Experimental results have shown that the weight losses of the mild steel and aluminum materials are 7.45% and 16.7%, respectively, in 5% wt hydrochloric acid after three weeks. The corrosive environment affected the strength of the joints and obtained an early failure on the joint region that leads to a reduction on the strength of the materials by almost 15% compared to the non-corroded joint. The joining of non-corroded similar steel obtained the highest maximum stress among all other specimens, where the maximum recorded stress was 140.5MPa as compared to 125MPa for corroded specimen. Furthermore, the mode of failure and hardness tests were obtained and analyzed for all specimens. A significant reduction in the hardness of the materials after exposure to the HCl acid was observed
Tramadol: A valuable treatment for pain in Southeast Asian countries
Background: The supply of controlled drugs is limited in the Far East, despite the prevalence of health disorders that warrant their prescription. Reasons for this include strict regulatory frameworks, limited financial resources, lack of appropriate training amongst the medical profession and fear of addiction in both general practitioners and the wider population. Consequently, the weak opioid tramadol has become the analgesic most frequently used in the region to treat moderate to severe pain.Methods: To obtain a clearer picture of the current role and clinical use of tramadol in Southeast Asia, pain specialists from 7 countries in the region were invited to participate in a survey, using a questionnaire to gather information about their individual use and experience of this analgesic.Results: Fifteen completed questionnaires were returned and the responses analyzed. Tramadol is used to manage acute and chronic pain caused by a wide range of conditions. Almost all the specialists treat moderate cancer pain with tramadol, and every one considers it to be significant or highly significant in the treatment of moderate to severe non-cancer pain. The reasons for choosing tramadol include efficacy, safety and tolerability, ready availability, reasonable cost, multiple formulations and patient compliance. Its safety profile makes tramadol particularly appropriate for use in elderly patients, outpatients, and for long-term treatment. The respondents strongly agreed that tighter regulation of tramadol would reduce its medical availability and adversely affect the quality of pain management. In some countries, there would no longer be any appropriate medication for cancer pain or the long-term treatment of chronic pain.Conclusions: In Southeast Asia, tramadol plays an important part in the pharmacological management of moderate to severe pain, and may be the only available treatment option. If it were to become a controlled substance, the standard of pain management in the region would decline
The rise of rapid implementation: a worked example of solving an existing problem with a new method by combining concept analysis with a systematic integrative review
Background The concept of rapid implementation has emerged in the literature recently, but without a precise definition. Further exploration is required to distinguish the concept’s unique meanings and significance from the perspective of implementation science. The study clarifies the concept of rapid implementation and identifies its attributes, antecedents, and consequences. We present a theoretical definition of rapid implementation to clarify its unique meaning and characteristics. Methods Rodgers evolutionary concept analysis method, combined with a systematic integrative review, were used to clarify the concept of rapid implementation. A comprehensive search of four databases, including EMBASE, MEDLINE, SCOPUS, and WEB OF SCIENCE was conducted, as well as relevant journals and reference lists of retrieved studies. After searching databases, 2442 papers were identified from 1963 to 2019; 24 articles were found to fit the inclusion criteria to capture data on rapid implementation from across healthcare settings in four countries. Data analysis was carried out using descriptive thematic analysis. Results The results locate the introduction of rapid implementation, informed by implementation science. Guidance for further conceptualisation to bridge the gap between research and practice and redefine rigour, adapting methods used (current approaches, procedures and frameworks), and challenging clinical trial design (efficacy-effectiveness-implementation pipeline) is provided. Conclusions It is possible that we are on the cusp of a paradigm shift within implementation brought about by the need for faster results into practice and policy. Researchers can benefit from a deeper understanding of the rapid implementation concept to guide future implementation of rapid actionable results in clinical practice
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