Study on Transient Air Permeability of Concrete under Different Curing Conditions

2014 ◽  
Vol 629-630 ◽  
pp. 223-228
Author(s):  
Song Mu ◽  
Ye Wu ◽  
Qian Jiang ◽  
Liang Shi

Quality of concrete cover is a key factor for concrete durability. In fact, the quality of concrete cover has close relationship with mixture design and curing condition. Present study adopted transient test of air permeability to study on affecting factors of air permeability of concrete. Results dedicated that curing condition was the most important factor to affect transient air permeability of concrete. Adequate curing is required to decrease effectively the air permeability, and low ratio of W/B is helpful to reduce air permeability. Air permeability of concrete samples, added with fly ash or slag powder, was more sensitive to dry curing than standard curing. Besides, CaO based expansive agent effectively decreased coefficient of air permeability at the adequate curing condition

2008 ◽  
Vol 53-54 ◽  
pp. 197-200
Author(s):  
Xiao Cun Xu ◽  
Wen Bing Zheng ◽  
Bin Jiang ◽  
Shu Cai Yang

Polishing is usually the last working procedure of making die surface. The roughness of die surface affects using performance of die directly; therefore, surface roughness is a key factor to scale quality of die surface. The paper focuses on affecting factors of polishing surface roughness, including the rotation speed of polishing head, floating force on polishing head, pass of polishing head movement, feeding rate of polishing head, and size of abrasive particles. Then, establish the parameters database in order to select appropriate technological parameters expediently. These results are used as operating guides for applications of die polisher.


2019 ◽  
Vol 15 (1) ◽  
pp. 31-39
Author(s):  
Oluwadara Oluwaseun Alegbeleye ◽  
Wasiu Akinloye Oyebisi Afolabi ◽  
Beatrice Oluwatoyin Opeolu ◽  
Amin Mousavi Khaneghah

Background: Bacterial counts in ready-to-eat foods are a key factor in assessing the microbiological quality and safety of food. Periodic assessment of the microbiological quality of food is necessary to develop a robust database and help to ensure food safety. </P><P> Methods: The bacterial contamination of a total of 336 bread samples collected from two bakeries and 10 vendors in Ojoo Area of Ibadan, Oyo-State, Nigeria (December 2014 -June 2015) was evaluated. The microbiological quality of the bread loaves was investigated using standard microbiological methods (morphological, phenotypic and molecular characterization). </P><P> Results: The results showed that the number of contaminated samples among the vended bread samples was higher than the bakery bread samples and can be summarized as Bacillus megaterium (4.30%), Staphylococcus arlettae (0.005%), Staphylococcus saprophyticus (2.78%), Citrobacter freundii (2.40%), Bacillus flexus (1.64%), Bacillus species (49.59%), Pseudomonas aeruginosa (4.12%), Pseudomonas fluorescens (0.92%), Pseudomonas species (0.045%), Escherichia coli (30.44%) Klebsiella sp. (0.040%) and Aeromonas hydrophila (3.72%). </P><P> Conclusion: The findings demonstrate that the bread samples which become contaminated after transport and handling can be considered a potential hazard to human health in the area. More stringent adherence to food safety regulations should be encouraged and enforced by the appropriate authorities. The findings of this study may be adopted to improve the hygienic conditions of bread distribution chain in the area as well as in other regions of the World.


2018 ◽  
Author(s):  
Dave L Dixon ◽  
William L Baker

BACKGROUND The impact and quality of a faculty members publications is a key factor in promotion and tenure decisions and career advancement. Traditional measures, including citation counts and journal impact factor, have notable limitations. Since 2010, alternative metrics have been proposed as another means of assessing the impact and quality of scholarly work. The Altmetric Attention Score is an objective score frequently used to determine the immediate reach of a published work across the web, including news outlets, blogs, social media, and more. Several studies evaluating the correlation between the Altmetric Attention Score and number of citations have found mixed results and may be discipline-specific. OBJECTIVE To determine the correlation between higher Altmetric Attention Scores and citation count for journal articles published in major pharmacy journals. METHODS This cross-sectional study evaluated articles from major pharmacy journals ranked in the top 10% according to the Altmetric Attention Score. Sources of attention that determined the Altmetric Attention Score were obtained, as well each articles open access status, article type, study design, and topic. Correlation between journal characteristics, including the Altmetric Attention Score and number of citations, was assessed using the Spearman’s correlation test. A Kruskal-Wallis 1-way analysis of variance (ANOVA) was used to compare the Altmetric Attention Scores between journals. RESULTS Six major pharmacy journals were identified. A total of 1,376 articles were published in 2017 and 137 of these represented the top 10% with the highest Altmetric Attention Scores. The median Altmetric Attention Score was 19 (IQR 15-28). Twitter and Mendeley were the most common sources of attention. Over half (56.2%) of the articles were original investigations and 49.8% were either cross-sectional, qualitative, or cohort studies. No significant correlation was found between the Altmetric Attention Score and citation count (rs=0.07, P = 0.485). Mendeley was the only attention source that correlated with the number of citations (rs=0.486, P<0.001). The median Altmetric Attention Score varied widely between each journal (P<0.001). CONCLUSIONS The overall median Altmetric Attention score of 19 suggests articles published in major pharmacy journals are near the top 5% of all scientific output. However, we found no correlation between the Altmetric Attention Score and number of citations for articles published in major pharmacy journals in the year 2017.


Author(s):  
Audrius Dėdelė ◽  
Auksė Miškinytė

Sustainable mobility is becoming a key factor in improving the quality of life of the residents and increasing physical activity (PA) levels. The current situation of sustainable mobility and its analysis is a first step in understanding the factors that would encourage residents to discover and choose alternative modes of travel. The present study examined the factors that encourage the choice of active modes of travel among urban adult population. Walking and cycling were analyzed as the most sustainable forms of urban mobility from the perspective of car and public transport (PT) users. Total of 902 subjects aged 18 years or older were analyzed in the study to assess commuting habits in Kaunas city, Lithuania. The majority (61.1%) of the respondents used a passenger vehicle, 28.2% used PT, and only 13.5% used active modes of travel. The results showed that safer pedestrian crossings, and comfortable paths were the most significant factors that encourage walking. A wider cycling network, and bicycle safety were the most important incentives for the promotion of cycling. Our findings show that the main factors encouraging walking and cycling among car and PT users are similar, however, the individual characteristics that determine the choice of these factors vary significantly.


2021 ◽  
Vol 80 (Suppl 1) ◽  
pp. 1057.2-1057
Author(s):  
Y. Liu ◽  
Y. Huang ◽  
Q. Huang ◽  
S. Sun ◽  
Z. Ji ◽  
...  

Background:Exosomes in synovial fluid (SF) has a close relationship with the pathogenesis of rheumatiod arthritis. As a complex biological fluid, SF presents challenges for exosomes isolation using standard methods, such as ExoquickTM kit and ultracentrifugation.Objectives:The study aims to compared the quality of exosomes separated by ExoquickTM kit (TM), ExoquickTM kit+ExoquickTC kit (TM-TC), ultracentrifugation (UC) and TM-TC+UC(TM-TC-UC) from SF.Methods:Exosomes was separated by TM, TM-TC, UC and TM-TC-UC respectively. The size and concentrations of exosomes were detected by high sensitivity flow cytometry for nanoparticle analysis. Total protein and RNA were extracted from exosomes. SDS-PAGE was used to detect the protein distribution of exosomes. Western blot was used to examine the level of albumin and exosomes marker (TSG101 and CD81).Results:There was no statistic difference in the diameters of exosomes separated by the four methods. The concentrations of exosomes in TM, TM-TC, TM-TC-UC and UC were (5.65±0.93), (3.02±1.19), (1.67±0.25) and (4.61±0.73) *109Particles/mL. The protein concentrations of exosomes separated by the four methods were consistent with the concentrations of exosomes. SDS-PAGE showed that the protein distribution of exosomes separated by the four methods were different. Low levels of albumin were detected in TM-TC and TM-TC-UC, while high levels of albumin in TM and UC. Total RNA concentrations from exosomes in TM-TC was higher than other groups.Conclusion:TM-TC can be used to obtain higher quality exosomes from SF for the study of exosome-enriched components.References:[1]Helwa I, et al, A Comparative Study of Serum Exosome Isolation Using Differential Ultracentrifugation and Three Commercial Reagents. PloS one, 2017. 12(1): p. e0170628-e0170628.Figure 1.A: SDS-PAGE showed the protein distribution of exosomes; B: the detection of albumin, TSG101 and CD81 by western blot.Disclosure of Interests:None declared


Author(s):  
Iwona Kowalczuk ◽  
Jerzy Gębski

The aim of the study was to examine whether, and to what extent, fear of contracting Covid-19 and compliance with the mandatory rules of isolation affected Polish adults’ nutritional behaviors. The online study was carried out during the first wave of the pandemic on a sample of 926 adults. Through cluster analysis, three groups of respondents were isolated: 1. People who fear a Covid-19 infection and follow the isolation rules (FFR), 2. People moderately afraid of the disease and following the rules loosely (MFFR), 3. People who are not afraid of the infection and do not follow the rules of isolation. (NFFR). The clusters were profiled with consideration of different aspects of eating behaviors as well as socio-demographic and economic features. The results of the study show a close relationship between the level of fear of contracting Covid-19 and the degree to which isolation rules are followed. These two factors were found to have a significant impact on eating behaviors, such as food purchases, eating patterns, and levels of consumption. It was stated that the FFR group changed their eating behaviors the most in terms of food purchasing, eating habits (excluding diversity and quality of diet), and food product consumption. The greatest stability in the majority of the analyzed areas of nutritional behaviors was observed in the MFFR cluster. The NFFR group shown the greatest decrease both in regularity and quality of their meals. This group also exhibited a significant increase in the consumption of alcoholic beverages. The results of the study can be useful in the decision making process when introducing restrictions or managing information. They also point to the need for extensive nutritional education focused on explaining the relationship between nutrition and health during a pandemic.


Author(s):  
Jessica Bowie ◽  
Oliver Brunckhorst ◽  
Robert Stewart ◽  
Prokar Dasgupta ◽  
Kamran Ahmed

Abstract Purpose Body image, self-esteem, and masculinity are three interconnected constructs in men with prostate cancer, with profound effects on quality of life. This meta-synthesis aimed to evaluate all known qualitative studies published studying the effect of prostate cancer on these constructs. Methods A systematic review utilising PubMed, Embase, MEDLINE, and PsycINFO databases up to May 2020 was conducted in line with PRISMA and ENTREQ guidelines. All qualitative studies of men’s experiences with body image, self-esteem, and masculinity whilst living with prostate cancer were included. A thematic meta-synthesis was conducted to identify emergent descriptive and analytical themes under the main study constructs. Results Of 2188 articles identified, 68 were included. Eight descriptive themes were identified under two analytical themes: ‘Becoming a Prostate Cancer Patient’ and ‘Becoming a Prostate Cancer Survivor’. These described the distress caused by changes to body image, sexual functioning, sense of masculinity, and self-esteem, and the subsequent discourses men engaged with to cope with and manage their disease. A key element was increased flexibility in masculinity definitions, and finding other ways to re-affirm masculinity. Conclusions Prostate cancer has an important effect on men’s health post-diagnosis, and we identified strong relationships between each construct evaluated. The role of hegemonic masculinity is important when considering men’s coping mechanisms and is also a key factor when addressing these constructs in counselling post-treatment. Implications for Cancer Survivors This meta-synthesis provides key topics that uniquely affect prostate cancer survivors, enabling these patients to be effectively counselled, and have their concerns recognised by clinicians.


Author(s):  
Ioulia Kokka ◽  
Iraklis Mourikis ◽  
Nicolas C. Nicolaides ◽  
Christina Darviri ◽  
George P. Chrousos ◽  
...  

Adolescent suse internet via several devices to gather information or communicate. Sleep, as a key factor of adolescents’ development, contributes to their physical and mental health. Over the past decades insufficient sleep among adolescents has been wide spread, and one of its attributing factors is the increased availability of technology. This review aims to investigate the body of evidence regarding the impact of problematic internet use on adolescent sleep. Extensive search of databases was performed according to PRISMA guidelines for studies published within the last decade, regarding subjects aged 10–19. The final step of the search yielded 12 original studies. The quality of extracted data was evaluated with the AXIS tool, in order to estimate the risk of bias. All studies showed a negative correlation between adolescent sleep and problematic internet use. It was found to affect sleep quality and quantity and provoke insomnia symptoms. Interestingly, adolescent’s sex, parental educational level, type of family and use for leisure or academic reasons appeared as affecting factors of the problematic internet use-sleep relationship. Problematic internet use has several effects on adolescents’ sleep. Results of relevant studies should be embedded in educational interventions addressed to adolescents as well as parents, to eliminate the negative outcomes of problematic internet use on sleep and adolescence’s health in general.


Proceedings ◽  
2018 ◽  
Vol 2 (23) ◽  
pp. 1455 ◽  
Author(s):  
Dina Czajczyńska ◽  
Renata Krzyżyńska ◽  
Hussam Jouhara

In 2016 4.94 million tonnes of tyres were produced. Each tyre eventually become waste and pyrolysis has been considered an effective way of utilizing scrap tyres for several decades. However, pyrolysis has failed many times because the process has a great energy demand and the quality of products is unstable or insufficient for commercial use. Usually plants are focused on the production of pyrolytic oil or char and the gaseous phase is only a by-product. In this paper the importance of composition and quality of pyrolytic gas is emphasized. The main chemical properties make this gas a valuable biofuel that may satisfy energy requirements of the whole process (except for the start-up phase). Available data from literature concerning composition and other features of the pyrolytic gas from scrap tyres obtained at temperatures up to 1000 °C are compared with experimental results. The quality of evolved gases is discussed in the context of the Industrial Emissions Directive (IED), too. Finally, an analysis of the mass balances obtained allows a decision about the business profile and profitability.


2020 ◽  
pp. 073346482096261
Author(s):  
Carol Opdebeeck ◽  
Michael A. Katsaris ◽  
Anthony Martyr ◽  
Ruth A. Lamont ◽  
James A. Pickett ◽  
...  

Pet ownership has been associated with positive outcomes in many populations, yet the associations with physical and psychological wellbeing in people with dementia remain unclear. The current study used baseline data from 1,542 people living at home with mild-to-moderate dementia from the Improving the experience of Dementia and Enhancing Active Life (IDEAL) programme. Regression analyses investigated associations of pet ownership and pet care with self-reports of walking, loneliness, depression, and quality of life (QoL). After adjusting for covariates, having any pet was associated with higher likelihood of walking over 3 hr in the last week. Those with a dog and who were involved in its care were less likely to be lonely than those with no dog. Having any pet but no involvement in its care was associated with increased depression and decreased QoL compared with those without a pet. The key factor in the associations was involvement in the care of the pet by the person with dementia.


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