scholarly journals Strengthening of Structure by Repair, Rehabilitation, Retrofitting and Restoration

2020 ◽  
pp. 130-136
Author(s):  
Shakti Singh ◽  
Devender Kumar
Keyword(s):  
Advanced Materials ◽  
Structural Failure ◽  
Chemical Attack ◽  
Large Numbers ◽  
Alkali Aggregate Reactivity ◽  
Materials Used ◽  
Seismic Forces ◽  
Concrete Elements ◽  
Design Construction

All structures have a assumed use able life, which depends on the weathering action, chemical attack, embedded metals, alkali-aggregate reactivity, fire, due to overload, seismic forces, quality of materials used, techniques, workmanship etc. The large numbers of monuments, which are cherished heritage structures have stood well over a period of time due to best material and periodical maintenance. But some of these have shown signs of distress due to age, aggressive natural environment/industrial pollution etc. Further, distress gets aggravated due to overcrowding and misuse of buildings. Some Buildings have also failed due to faulty design, construction, bad quality materials, poor workmanship etc. The various causes of structural failure and the principles of rehabilitation of structures are discussed. In the structures, the cracks are generated due to different causes e.g. in some cases cracks are caused after the structure has been completed for a few years which results in shortening of life and strength of structure. The main criteria is how to repair a reinforced concrete elements of structures and for this the skills, knowledge, and experience required to repair damaged or deteriorated structures are decidedly different from those required to build new structures. The purpose of this paper is to justify the latest techniques, advanced materials and various requirements of repairing work to obstruct the deterioration which is necessary and economical than to reconstruct the building.

scholarly journals Recent Advances in Electrochemical and Optical Sensing of Dopamine

Sensors ◽  
2020 ◽  
Vol 20 (4) ◽  
pp. 1039 ◽  
Author(s):  
Faten Bashar Kamal Eddin ◽  
Yap Wing Fen
Keyword(s):  
Neurological Disorders ◽  
Treatment Cost ◽  
Biological Fluids ◽  
Biological Species ◽  
Advanced Materials ◽  
Sensor Surface ◽  
Materials Used

Nowadays, several neurological disorders and neurocrine tumours are associated with dopamine (DA) concentrations in various biological fluids. Highly accurate and ultrasensitive detection of DA levels in different biological samples in real-time can change and improve the quality of a patient’s life in addition to reducing the treatment cost. Therefore, the design and development of diagnostic tool for in vivo and in vitro monitoring of DA is of considerable clinical and pharmacological importance. In recent decades, a large number of techniques have been established for DA detection, including chromatography coupled to mass spectrometry, spectroscopic approaches, and electrochemical (EC) methods. These methods are effective, but most of them still have some drawbacks such as consuming time, effort, and money. Added to that, sometimes they need complex procedures to obtain good sensitivity and suffer from low selectivity due to interference from other biological species such as uric acid (UA) and ascorbic acid (AA). Advanced materials can offer remarkable opportunities to overcome drawbacks in conventional DA sensors. This review aims to explain challenges related to DA detection using different techniques, and to summarize and highlight recent advancements in materials used and approaches applied for several sensor surface modification for the monitoring of DA. Also, it focuses on the analytical features of the EC and optical-based sensing techniques available.

scholarly journals The impact of the quality of materials on the differentiation of the reliability of a reinforced concrete beam

2019 ◽  
Vol 262 ◽  
pp. 06009
Author(s):  
Izabela Skrzypczak ◽  
Lidia Buda-Ożóg ◽  
Joanna Kujda
Keyword(s):  
Quality Control ◽  
Reinforced Concrete ◽  
Reinforced Concrete Beam ◽  
Reliability Indicators ◽  
Load Factors ◽  
Materials Used ◽  
Available Information ◽  
The Impact ◽  
Concrete Elements

Eurocod PN-EN 1990 „The basis for structural design” includes general principles for the differentiation of reliability taking into account the consequences of failure. Constructions are classified into three reliability classes RC1 to RC3, for which target reliability indicators have been defined. For the RC2 reliability class the basic values of partial coefficients in relation to materials and loads for persistent and transient computational situations were given. However, Eurocod PN-EN 1992-1-1, „Design concrete structures”, proposes to reduce partial coefficients by including quality control of production and available information on the heterogeneity of the materials used. The evaluation of standard recommendations regarding material partial coefficients was made on the basis of analysis of the reinforced concrete bending beam. The standard recommendations provide different levels of reliability. Elements designed in accordance with EN 1992-1-1 to reduce the value of partial factors with tighter quality control and reliability of reinforced concrete elements at RC2 reliability level may not be sufficient for load factors more than 0. 4.

Urban stormwater: the analysis of the failure of the alternative techniques and the management of quality

1995 ◽  
Vol 32 (1) ◽  
pp. 33-39
Author(s):  
E. Alfakih ◽  
S. Barraud ◽  
Y. Azzout ◽  
B. Chocat
Keyword(s):  
Stormwater Management ◽  
Difficult Problem ◽  
Management Approach ◽  
Alternative Technique ◽  
Urban Stormwater ◽  
Urban Stormwater Management ◽  
Porous Pavement ◽  
Alternative Techniques ◽  
Design Construction

The implementation of alternative techniques in urban stormwater management is a difficult problem in terms of choice, design, construction, and operating. We applied a quality management approach to try and have a better understanding of these techniques. The quality of an alternative technique in urban stormwater management is defined; the factors that lead to failures were identified and analysed. In order to reduce these factors, tools were developed, and measures that allow the achievement of the necessary standard of quality are suggested. In this article, all the illustrations refer to the porous pavement technique.

CUIDADOS BUCAIS EM PACIENTES VENTILADOS MECANICAMENTE: CONHECIMENTO DE ENFERMEIROS DE UM HOSPITAL ESCOLA

2018 ◽  
Vol 8 (4) ◽  
Author(s):  
Gérsica Sampaio Silva ◽  
Fernanda Alves Ferreira Gonçalves ◽  
Bárbara Ribeiro Miquelin Bueno ◽  
Georlucya Kátia Da Silva Ferreira ◽  
Ludmila Pinheiro Da Silva ◽  
...  
Keyword(s):  
Oral Hygiene ◽  
Oral Care ◽  
Cross Sectional Study ◽  
Cross Sectional ◽  
Mechanically Ventilated ◽  
Mechanically Ventilated Patients ◽  
Complicating Factors ◽  
Materials Used ◽  
Ventilated Patients

Objetivo: Avaliar o conhecimento acerca dos cuidados bucais realizados por enfermeiros a pacientes ventilados mecanicamente. Método: Estudo transversal, realizado em um hospital escola de Goiânia/Goiás. A coleta de dados deu-se por meio de questionário estruturado. Resultados: Os enfermeiros conhecem as medidas recomendadas sobre higiene bucal. Os fatores dificultadores encontrados foram a falta de pessoal (21,7%), falta de tempo (16,7%) e trabalhos burocráticos (15%). Contudo ainda existem lacunas no que se refere a produtos e materiais utilizados na higiene bucal. Conclusão: As Lacunas e os fatores dificultadores sinalizados nesse estudo merecem reflexão, como forma de avaliar a qualidade do cuidado oferecido.Descritores: Biofilme; Higiene Bucal; Cuidados de enfermagem.ORAL CARE IN MECHANICALLY VENTILATED PATIENTS: KNOWLEDGE OF NURSES FROM A SCHOOL HOSPITALObjective: To evaluate the knowledge about oral care performed by nurses in mechanically ventilated patients. Methods: a cross-sectional study, conducted in a teaching hospital of Goiania/Goias. The data collection was performed by means of a structured questionnaire. Results: The nurses know the measures recommended on oral hygiene. The complicating factors found were the lack of personnel (21.7%), lack of time (16.7%) and work on tape (15%). However there are still gaps in relation to products and materials used in oral hygiene. Conclusion: The gaps and the factors complicating factors indicated in this study deserve consideration, as a means of evaluating the quality of care offered.Keywords: Biofilm; Oral hygiene; Nursing care.CUIDADO ORAL EN PACIENTES CON VENTILACIÓN MECÁNICA: EL CONOCIMIENTO DE LAS ENFERMERAS DEL HOSPITAL ESCUELAObjetivo: Evaluar el conocimiento sobre el cuidado bucal realizadas por enfermeras en pacientes ventilados mecánicamente. Métodos: Estudio transversal, realizado en un hospital de Goiania y Goias. La recolección de datos se realizó por medio de un cuestionario estructurado. Resultados: Las enfermeras saben las medidas recomendadas en la higiene bucal. Los factores encontrados fueron la falta de personal (21,7%), la falta de tiempo (16,7%) y trabajar en la cinta (15%). Sin embargo todavía hay lagunas en relación con los productos y los materiales utilizados en la higiene bucal. Conclusión: Las brechas y los factores factores indicados en este estudio merecen consideración, como medio de evaluar la calidad de la atención ofrecida.Palabras clave: Biofilme; Higiene Bucal; Atención de Enfermería.

Biomimetic Design of 3D Printed Tissue-engineered bone Constructs

2020 ◽  
Vol 16 ◽  
Author(s):  
Wei Liu ◽  
Shifeng Liu ◽  
Yunzhe Li ◽  
Peng Zhou ◽  
Qian ma
Keyword(s):  
Tissue Engineering ◽  
3D Printing ◽  
Advanced Materials ◽  
Bionic Design ◽  
Material Interfaces ◽  
Precise Control ◽  
Cell Printing ◽  
Biomimetic Scaffolds ◽  
3D Printed

Abstract:: Surgery to repair damaged tissue, which is caused by disease or trauma, is being carried out all the time, and a desirable treatment is compelling need to regenerate damaged tissues to further improve the quality of human health. Therefore, more and more research focus on exploring the most suitable bionic design to enrich available treatment methods. 3D-printing, as an advanced materials processing approach, holds promising potential to create prototypes with complex constructs that could reproduce primitive tissues and organs as much as possible or provide appropriate cell-material interfaces. In a sense, 3D printing promises to bridge between tissue engineering and bionic design, which can provide an unprecedented personalized recapitulation with biomimetic function under the precise control of the composition and spatial distribution of cells and biomaterials. This article describes recent progress in 3D bionic design and the potential application prospect of 3D printing regenerative medicine including 3D printing biomimetic scaffolds and 3D cell printing in tissue engineering.

Chitosan in Biomedical Engineering: A Critical Review

2019 ◽  
Vol 14 (2) ◽  
pp. 93-116 ◽  
Author(s):  
Shabnam Mohebbi ◽  
Mojtaba Nasiri Nezhad ◽  
Payam Zarrintaj ◽  
Seyed Hassan Jafari ◽  
Saman Seyed Gholizadeh ◽  
...  
Keyword(s):  
Quality Of Life ◽  
Biomedical Engineering ◽  
Biological Properties ◽  
Advanced Materials ◽  
Comprehensive Overview ◽  
Chemical Structures ◽  
Bio Imaging ◽  
Significant Attention ◽  
Unique Chemical

Biomedical engineering seeks to enhance the quality of life by developing advanced materials and technologies. Chitosan-based biomaterials have attracted significant attention because of having unique chemical structures with desired biocompatibility and biodegradability, which play different roles in membranes, sponges and scaffolds, along with promising biological properties such as biocompatibility, biodegradability and non-toxicity. Therefore, chitosan derivatives have been widely used in a vast variety of uses, chiefly pharmaceuticals and biomedical engineering. It is attempted here to draw a comprehensive overview of chitosan emerging applications in medicine, tissue engineering, drug delivery, gene therapy, cancer therapy, ophthalmology, dentistry, bio-imaging, bio-sensing and diagnosis. The use of Stem Cells (SCs) has given an interesting feature to the use of chitosan so that regenerative medicine and therapeutic methods have benefited from chitosan-based platforms. Plenty of the most recent discussions with stimulating ideas in this field are covered that could hopefully serve as hints for more developed works in biomedical engineering.

EVALUATION OF TRIBOTECHNICAL PROPERTIES OF THE COATING OBTAINED BY ELECTRIC SPARK HARDENING

2020 ◽  
Vol 4 (141) ◽  
pp. 157-163
Author(s):  
IL’YA ROMANOV ◽  
◽  
ROMAN ZADOROZHNIY
Keyword(s):  
Wear Resistance ◽  
Reference Sample ◽  
Optical Microscope ◽  
Research Purpose ◽  
Tribotechnical Properties ◽  
Uncoated Surface ◽  
Before And After ◽  
Materials Used ◽  
Friction Track

When applying coatings using various methods on the surfaces of moving parts that work in joints, it is important to make sure that the coatings are strong and wear-resistant in order to return them to their original resource. All existing hardening technologies and materials used to perform coatings have their own characteristics, therefore, the quality of the resulting coatings can be judged only after specific tests. (Research purpose) The research purpose is in evaluating the properties of the coating obtained by the method of electric spark hardening, and its ability to resist friction and mechanical wear. (Materials and methods) Authors conducted tests on the basis of the "Nano-Center" center for collective use. A coating was applied on the BIG-4M unit with a VK-8 hard alloy electrode, tribological properties were evaluated on a CSM Instruments TRB-S-DE-0000 tribometer, the width of the friction track was measured after the test using an inverted OLYMPUS gx51 optical microscope, and samples were weighed before and after the test on a VLR-200 analytical balance. Conducted research in accordance with GOST 23.224-86 and RD 50-662-88 guidelines. (Results and discussion) The article presents performed tests on the run-in and wear resistance of the coating. The samples were worked on with a step-by-step increase in the load. During the tests, the friction force was drawed on the diagram. Authors compared the results with the reference sample, an uncoated surface. (Conclusions) The resulting coating has better run-in and wear resistance compared to the standard, and the increase in wear resistance in dry friction conditions is very significant.

Scoundrels or Stars? Theory and Evidence on the Quality of Workers in Online Labor Markets

2016 ◽  
Vol 92 (1) ◽  
pp. 93-114 ◽  
Author(s):  
Anne M. Farrell ◽  
Jonathan H. Grenier ◽  
Justin Leiby
Keyword(s):  
Labor Markets ◽  
Data Availability ◽  
Accounting Research ◽  
Research Participants ◽  
Large Numbers ◽  
Research Designs ◽  
Online Labor Markets ◽  
Online Labor ◽  
Low Pay

ABSTRACT Online labor markets allow rapid recruitment of large numbers of workers for very low pay. Although online workers are often used as research participants, there is little evidence that they are motivated to make costly choices to forgo wealth or leisure that are often central to addressing accounting research questions. Thus, we investigate the validity of using online workers as a proxy for non-experts when accounting research designs use more demanding tasks than these workers typically complete. Three experiments examine the costly choices of online workers relative to student research participants. We find that online workers are at least as willing as students to make costly choices, even at significantly lower wages. We also find that online workers are sensitive to performance-based wages, which are just as effective in inducing high effort as high fixed wages. We discuss implications of our results for conducting accounting research with online workers. Data Availability: Contact the authors.

Animal Models and Alternatives in the Quality Control of Vaccines: Are In Vitro Methods or In Vivo Methods the Scientific Equivalent of the Emperor's New Clothes?

1995 ◽  
Vol 23 (1) ◽  
pp. 61-73
Author(s):  
Coenraad Hendriksen ◽  
Johan van der Gun
Keyword(s):  
Quality Control ◽  
Test Methods ◽  
In Vitro Test ◽  
Large Numbers ◽  
Alternative Approach ◽  
Inactivated Vaccines ◽  
Vitro Test

In the quality control of vaccine batches, the potency testing of inactivated vaccines is one of the areas requiring very large numbers of animals, which usually suffer significant distress as a result of the experimental procedures employed. This article deals with the potency testing of diphtheria and tetanus toxoids, two vaccines which are used extensively throughout the world. The relevance of the potency test prescribed by the European Pharmacopoeia monographs is questioned. The validity of the potency test as a model for the human response, the ability of the test to be standardised, and the relevance of the test in relation to the quality of the product are discussed. It is concluded that the potency test has only limited predictive value for the antitoxin responses to be expected in recipients of these toxoids. An alternative approach for estimating the potency of toxoid batches is discussed, in which a distinction is made between estimation of the immunogenic potency of the first few batches obtained from a seed lot and monitoring the consistency of the quality of subsequent batches. The use of animals is limited to the first few batches. Monitoring the consistency of the quality of subsequent batches is based on in vitro test methods. Factors which hamper the introduction and acceptance of the alternative approach are considered. Finally, proposals are made for replacement, reduction and/or refinement (the Three Rs) in the use of animals in the routine potency testing of toxoids.

scholarly journals Analysis of Quality of Backyard Compost and Its Potential Utilization as a Circular Bio-Waste Source

2021 ◽  
Vol 11 (10) ◽  
pp. 4392
Author(s):  
Apolka Ujj ◽  
Kinga Percsi ◽  
Andras Beres ◽  
Laszlo Aleksza ◽  
Fernanda Ramos Diaz ◽  
...  
Keyword(s):  
Crop Production ◽  
Basic Education ◽  
Raw Materials ◽  
Nutrient Content ◽  
Quality Analysis ◽  
Weed Seed ◽  
Quality Properties ◽  
Seed Dispersion ◽  
Materials Used

The use and quality analysis of household compost have become very important issues in recent years due to the increasing interest in local food production and safe, self-produced food. The phenomenon was further exacerbated by the COVID-19 pandemic quarantine period, which gave new impetus to the growth of small home gardens. However, the knowledge associated with making high-quality compost is often lacking in home gardeners. Therefore, the objective of this research was to find answers to the following questions: can the quality of backyard compost be considered safe in terms of toxicity and nutrient content? Can weed seed dispersion affect the usability of backyard compost? In general, can the circulation of organic matter be increased with the spread of home composting? In this study, 16 different house composts were analysed for stability, weed seed contamination, toxic elements, and nutrient content using analysis of variance. The results of the research showed that the quality properties of the composts (including their weed seed dispersion effect) were greatly influenced by the different techniques and raw materials used. The toxicity levels, as well as the content of macro and microelements, were within the parameters of safe-quality compost. The specific macronutrient (Ca, Mg) and micronutrient (Fe, Mn) contents of the tested composts have a similar and, in some cases, more favorable nutrient supply capacity in crop production than the frequently-used cow manure-based composts. With a plan of basic education on composting, there is potential to encourage farmyard composting.

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