A Review of Morphological and Chemical Properties of Porous Asphalt

Porous asphalt mixture is also known as gap graded mixture with less amount of fine aggregate has led the mixture contains high air voids, tends to make the mixture less durable and high porousity. Hence, past researchers has investigate on how to increase the strength of porous asphalt mixture by the addition of additive such as fiber and nanomaterials. The chemical and physical properties of porous asphalt mixture was highlighted in this paper to compare its structure, the bonding between the materials and its chemical composition that exist. This paper reviews on how additive affect the asphalt mixture in terms of Scanning Electron Microscopy (SEM), X-Ray Diffractions (XRD) and Fourier Transform Infrared Spectroscopy (FTIR). These tests are selected to improve the asphalt mixture according to the morphological and chemical properties of porous asphalt. This study is expected to identify the morphological and chemical composition of the materials in asphalt mixture

Befogged

Porous Asphalt (PA) is known as a highly permeable asphalt surface that design to be permeable pavements for stormwater control and reduce the stormwater runoff. However, the structure is subjected to damage from cracking, rutting, stripping, and rapid aging under the effects of repeated vehicle loading, hot climates, and heavy rainfall. To overcome this, PA needs to modify using high tensile strength like steel fiber. Thus, this study aims to evaluate the performance of PA with the addition of steel fiber and overcome the issue that is related to PA. A mixture contains varying percentages of steel fiber were assessed to check which samples gives the best performance as per the requirement by using laboratory tests which are LA Abrasion, Resilient Modulus, Marshall Stability, and Density. The results show that the additions of 0.6% steel fiber give the lowest value of abrasion, while 0.5% fiber content contributes the highest value of Resilient Modulus and Marshall Stability respectively. PA mixtures modified with steel fiber produce the performance enhancement of PA as a road surfacing material. It is concluded that the asphalt mixtures containing steel fibers could increase the stability and strength of the mix

Changes in gene expression patterns in the tumor microenvironment of head and neck squamous cell carcinoma under chemoradiotherapy depend on response

Chemoradiotherapy (CRT) is a standard treatment for advanced head and neck squamous cell carcinoma (HNSCC). Unfortunately, not all patients respond to this therapy and require further treatment, either salvage surgery or palliative therapy. The addition of immunotherapy to CRT is currently being investigated and early results describe a mixed response. Therefore, it is important to understand the impact of CRT on the tumor microenvironment (TME) to be able to interpret the results of the clinical trials. Paired biopsies from 30 HNSCC patients were collected before and three months after completion of primary CRT and interrogated for the expression of 1392 immune- and cancer-related genes. There was a relevant difference in the number of differentially expressed genes between the total cohort and patients with residual disease. Genes involved in T cell activation showed significantly reduced expression in these tumors after therapy. Furthermore, gene enrichment for several T cell subsets confirmed this observation. The analysis of tissue resident memory T cells (TRM) did not show a clear association with impaired response to therapy. CRT seems to lead to a loss of T cells in patients with incomplete response that needs to be reversed. It is not clear whether the addition of anti-PD-1 antibodies alone to CRT can prevent treatment failure, as no upregulation of the targets was measurable in the TME

Chloroquine as weekly chemoprophylaxis or intermittent treatment to prevent malaria in pregnancy in Malawi: a randomised controlled trial.

BACKGROUND: Sulfadoxine-pyrimethamine resistance threatens efficacy of intermittent preventive treatment of malaria during pregnancy, and alternative regimens need to be identified. With the return of chloroquine efficacy in southern Africa, we postulated that chloroquine either as an intermittent therapy or as weekly chemoprophylaxis would be more efficacious than intermittent sulfadoxine-pyrimethamine for prevention of malaria in pregnancy and associated maternal and newborn adverse outcomes. METHODS: We did an open-label, single-centre, randomised controlled trial at Ndirande Health Centre, Blantyre, in southern Malawi. We enrolled pregnant women (first or second pregnancy) at 20-28 weeks' gestation who were HIV negative. Participants were randomly assigned in a 1:1:1 ratio using a computer-generated list to either intermittent sulfadoxine-pyrimethamine (two doses of 1500 mg sulfadoxine and 75 mg pyrimethamine, 4 weeks apart), intermittent chloroquine (two doses of 600 mg on day 1, 600 mg on day 2, and 300 mg on day 3), or chloroquine prophylaxis (600 mg on day 1 then 300 mg every week). The primary endpoint was placental malaria in the modified intent-to-treat population, which consisted of participants who contributed placental histopathology data at birth. Secondary outcomes included clinical malaria, maternal anaemia, low birthweight, and safety. This trial is registered with ClinicalTrials.gov, number NCT01443130. FINDINGS: Between February, 2012, and May, 2014, we enrolled and randomly allocated 900 women, of whom 765 contributed histopathological data and were included in the primary analysis. 108 (14%) women had placental malaria, which was lower than the anticipated prevalence of placental malaria infection. Protection from placental malaria was not improved by chloroquine as either prophylaxis (30 [12%] of 259 had positive histopathology; relative risk [RR] 0·75, 95% CI 0·48-1·17) or intermittent therapy (39 [15%] of 253; RR 1·00, 0·67-1·50) compared with intermittent sulfadoxine-pyrimethamine (39 [15%] of 253). In protocol-specified analyses adjusted for maternal age, gestational age at enrolment, bednet use the night before enrolment, anaemia at enrolment, and malaria infection at enrolment, women taking chloroquine as prophylaxis had 34% lower placental infections than did those allocated intermittent sulfadoxine-pyrimethamine (RR 0·66, 95% CI 0·46-0·95). Clinical malaria was reported in nine women assigned intermittent sulfadoxine-pyrimethamine, four allocated intermittent chloroquine (p=0·26), and two allocated chloroquine prophylaxis (p=0·063). Maternal anaemia was noted in five women assigned intermittent sulfadoxine-pyrimethamine, 15 allocated intermittent chloroquine (p=0·038), and six assigned chloroquine prophylaxis (p>0·99). Low birthweight was recorded for 31 babies born to women allocated intermittent sulfadoxine-pyrimethamine, 29 assigned intermittent chloroquine (p=0·78), and 41 allocated chloroquine prophylaxis (p=0·28). Four women assigned intermittent sulfadoxine-pyrimethamine had adverse events possibly related to study product compared with 94 women allocated intermittent chloroquine (p<0·0001) and 26 allocated chloroquine prophylaxis (p<0·0001). Three women had severe or life-threatening adverse events related to study product, of whom all were assigned intermittent chloroquine (p=0·25). INTERPRETATION: Chloroquine administered as intermittent therapy did not provide better protection from malaria and related adverse effects compared with intermittent sulfadoxine-pyrimethamine in a setting of high resistance to sulfadoxine-pyrimethamine. Chloroquine chemoprophylaxis might provide benefit in protecting against malaria during pregnancy, but studies with larger sample sizes are needed to confirm these results. FUNDING: US National Institutes of Health

Volumetric Properties and Resilient Modulus of Stone Mastic Asphalt incorporating Cellulose Fiber

Stone mastic asphalt (SMA) is well known as a high coarse aggregate content that interlocks to form a stone skeleton that resist permanent deformation. However, it facing a lot of problems such as rutting and stripping because of the high temperature and repeated axial load. It also suffers with creep issue. The cellulose fiber is a type of synthetic fiber that can enhance the properties of asphalt mixture. Thus, the aim of this study is to utilize the cellulose fiber that has high tensile strength to overcome the problem of SMA. Among the tests involve are Resilient Modulus, Marshall Stability and Cantabro Loss. From the results, it shows that the addition of cellulose fiber improved the recovery ability of asphalt binder. From each test, the addition of 0.2% cellulose fiber contributes to lowest value of abrasion, while 0.3% producing highest value of resilient modulus. Thus, the addition of cellulose fiber is capable in enhancing the properties of SMA

Small but crucial : the novel small heat shock protein Hsp21 mediates stress adaptation and virulence in Candida albicans

Peer reviewedPublisher PD

Noncompliance of the occupational safety and health legislation in the Malaysian construction industry

Occupational Safety and Health Act 1994 (OSHA 1994) is a tool for the employer, employee and manufacturer to put efforts in securing safety, health and welfare at work place. But, the increase in prosecution cases under OSH legislation indicates the lack of compliance to the regulations. A prosecution can be translated as one of the frequently employed instruments for the enforcement of health and safety legislation. The objective of this study is to analyze the most common non-compliance cases of OSH legislative provision from 2005 until October 2017 compiled by the Department Occupational Safety and Health (DOSH). The data of the cases were analyzed using frequency distribution analysis and content analysis. The result of the study shows that the most non-compliance with OSH legislation in Malaysia relates to the general duties of employers and self-employed persons to their employees (Section 15(1)). The second most common non-compliance of OSHA is section 17 regarding employer's failure to provide safe work system. The third and fourth most common non-compliance of OSHA is section 32 and 29 regarding the employer's failure to report the accidents and the employer's failure to provide competent safety and health officer. To increase compliance to legislation, full top management commitment, active worker engagement and effective safety and health committee are amongst top preferred solutions

Causes of fatal construction accidents in Malaysia

Malaysia has moved fast to keep pace with the changes of times as the country aspires to achieve strong economic growth and to chart its course as a developed nation by the year 2020. The construction industry is one of the important sectors for nations to develop our country's economy and thus able to improve our competitiveness. However, in line with the positive growth of the economy, the construction sector also contributes to the high accident fatality rate. Construction workers are often exposed to various inherent risks associated with working conditions on construction sites. Although various approaches have been implemented in order to prevent accidents, the statistic indicates further improvement need to be taken fast. The objective of the study is to analyse the statistics and causes of fatal accidents at construction sites in Malaysia. The study focuses on 129 fatal construction accident cases based on database and document kept by the Malaysian authority, such as Department of Occupational Safety and Health (DOSH) and Social Security Organisation (SOCSO). The collected data were analyzed using frequency analysis and content analysis. The analysis shows that the number of fatal accidents is increasing every year. In the last five years, statistic from SOCSO and DOSH has shown an increasing number of fatal accident cases for about 231.9% and 125.8% respectively. The top three causes of fatal construction accidents are unsafe methods, the unique nature of industry and job site conditions. Whereas, the leading sub-causes are work at high elevation, incorrect or no work procedure and failure of structure

Effects of black rice husk ash on asphalt mixture under aging condition

The scarcities of natural resources and increment in the waste production rates have promoted efforts to investigate the potential incorporation of various by-products in roads construction and maintenance. Various types of waste materials have been investigated, assessed and evaluated for utilization and practiced in the industry. Reusing of waste materials such as black rice husk ash (BRHA) in asphaltic concrete (AC) was considered as one of the proper management of the waste, which ensure economic and environmental benefits. This study was investigated BRHA effects on the properties and performance of asphalt mixture under different aging condition. The BRHA was added in the AC14 mixture in a proportion of 0%, 2%, 4% and 6% by weight of bitumen. The optimum bitumen content was 5% and the bitumen used was 60/70 penetration grades. The asphalt mixture for each fraction was prepared in three different aging conditions i.e. un-aging (UA), short term aging (STA) and long term aging (LTA). The performance of the asphalt mixtures was evaluated by Marshall Stability and resilient modulus. The results indicate that asphalt mixtures consisting of BRHA have exhibited better performance in term of stability and resilient modulus when compared to the conventional asphalt mixtures. The short term and long term aging mixtures considerably produced higher performance than the un-aging mixtures. However, the LTA performed better than of the STA mixtures. Finally, the optimum additional percentage of BRHA was in the range of 4 - 6% since its produce excellent values in most circumstances

Role of CYP27A in cholesterol and bile acid metabolism

The CYP27A gene encodes a mitochondrial cytochrome P450 enzyme, sterol 27-hydroxylase, that is expressed in many different tissues and plays an important role in cholesterol and bile acid metabolism. In humans, CYP27A deficiency leads to cerebrotendinous xanthomatosis. To gain insight into the roles of CYP27A in the regulation of cholesterol and bile acid metabolism, cyp27A gene knockout heterozygous, homozygous, and wild-type littermate mice were studied. In contrast to homozygotes, heterozygotes had increased body weight and were mildly hypercholesterolemic, with increased numbers of lipoprotein particles in the low density lipoprotein size range. Cyp7A expression was not increased in heterozygotes but was in homozygotes, suggesting that parts of the homozygous phenotype are secondary to increased cyp7A expression and activity. Homozygotes exhibited pronounced hepatomegaly and dysregulation in hepatic cholesterol, bile acid, and fatty acid metabolism. Hepatic cholesterol synthesis and synthesis of bile acid intermediates were increased; however, side chain cleavage was impaired, leading to decreased bile salt concentrations in gallbladder bile. Expression of Na-taurocholate cotransporting polypeptide, the major sinusoidal bile salt transporter, was increased, and that of bile salt export pump, the major canalicular bile salt transporter, was decreased. Gender played a modifying role in the homozygous response to cyp27A deficiency, with females being gen