Effect of Calcium Sulphate on the Geotechnical Properties of Stabilized Clayey Soils

An experimental investigation was undertaken to study the effect of calcium sulphate (CaSO4.2H2O) on the behaviour of the grey clay (GS) and red clay (RS) soils stabilized with lime (L), natural pozzolana (NP) and their combination (L-NP). In this study, the geotechnical properties investigated are respectively, the Atterberg limits on samples cured for 1 to 30 days to assess the diffusion time effect of CaSO4.2H2O (DTC) in the soil paste and the unconfined compressive strength (UCS) on samples cured for 7 to 120 days. The results show that both GS and RS samples can be successfully stabilized with L alone or with L-NP which substantially reduce their plasticity index (PI) and increase their UCS. On the other hand, a negligible effect was reported when the NP is used alone. However, when combining a fraction of CaSO4.2H2O to samples containing L or L-NP, a further decrease in the PI is observed. In addition, higher UCS values are recorded

Stabilization of Algerian Clayey Soils with Natural Pozzolana and Lime

Cohesive soils with a high plasticity index present difficulties in construction operations because they usually contain expansive clay minerals. However, the engineering properties of soils can be improved by different techniques. The aim of this paper is to study the effect of using lime, natural pozzolana or a combination of both lime and natural pozzolana on plasticity, compaction and shear strength of two clayey soils classified as CH and CL according to the unified soil classification system (USCS). The obtained results indicated that for CH class clay soil, the plasticity index decreased significantly for samples stabilized with lime. On the other hand, for the soil classified as CL class clay, a high decrease in the plasticity index value was observed for samples stabilized with natural pozzolana compared to those stabilized with lime. Also, both the cohesion and internal friction angle in lime added samples were demonstrated to increase with time. The combination of lime and natural pozzolana exhibits a significant effect on the enhancement of both the cohesion and  internal friction angle at later stages. The lime-natural pozzolana combination appears to produce higher shear strength parameters than lime or natural pozzolana used alone

Preliminary findings on the correlation of saliva pH, buffering capacity, flow rate and consistency in relation to waterpipe tobacco smoking

The aim of the present comparative study was to compare some salivary characteristics between exclusive waterpipe smokers (EWPS) and non-smokers. 72 males (36 EWPS) were recruited. The volume of stimulated saliva was determined and divided by the duration of saliva collection. The pH was measured directly using a pH meter. The buffering capacity was determined using a quantitative method which involved the addition of 10 μl HCl. Up to a total of 160 μL was titrated up to obtain a pH titration curve. At 50 μL of titrated HCl, buffering capacity was ranked into three categories: high, medium and low. EWPS and nonsmoker groups had similar flow rates (1.81 ± 0.79 and 1.78 ± 1.14 mL min-1) and similar baseline pH (6.60 ± 0.37 and 6.76 ± 0.39). Statistically significant differences in the two groups’ pH were observed from 30 to 160 μL of titrated up HCl. At 50 μL of titrated up HCl, the EWPS group compared to the non-smoker group had a significantly higher pH (4.79 ± 0.72 vs. 5.32 ± 0.79). To conclude, waterpipe tobacco smoking alters the buffering capacity but does not alter either salivary flow rates or the baseline pH and consistency

Juvenile recurrent parotitis in a 4-year-old patient: a case report

Juvenile recurrent parotitis (JRP) is a rare disease. It is most commonly occurring between the ages of 3 and 5 years, that classically resolves at adolescence. It is characterized by recurrent non-suppurative parotitis, with several acute inflammatory episodes per year. The parotid´s swelling tends to be unilateral, but it can occur bilaterally, with a more predominant side. The aim of this work was to present a case report that highlights signs and symptoms of this unusual condition and to stress on the value of ultrasonography as an aid to diagnosis

The Traumatic Effect of the Japanese War on Women in Rani Manicka’s Selected Novels

The Second World War which lasted from 1939-1945 left a deep dent in the lives of many victims in the world. The four-year Japanese rule in Malaya created a permanent scar in the hearts of the Malayans which lingered on even after many decades. The sufferings of the Malayan people under the inhuman Japanese army are clearly depicted in the two novels selected for this research, Rani Manicka’s The Rice Mother (2002) and The Japanese Lover (2010). The novels are about how women are subjected to the effects of war during the Japanese occupation, the pain of separation from a mother and her child, and the challenges a woman goes through to survive within a community. Manicka has used the Japanese occupation in Malaya as part of the settings for both novels. The characters will be studied under the light of trauma theory to highlight the irreparable damages caused by war on the psyche and the emotions of the characters as portrayed in the two novels. Trauma describes experiences that are emotionally painful and distressing whereby the victims face the inability to cope with life and it leaves behind a fundamental life-altering effect. This study aims to highlight the atrocities of the Japanese army in Malaya by studying the female characters in the selected novels. Secondly, this study will analyze the damages brought by the war to the female characters in the novels using the trauma theory and finally show how the war left a permanent damage in the lives of the female victims. The novelist highlights the injustices done to women in such societies and how they suffer even more after colonization. This double marginalization shatters and traumatizes the female identities. Therefore, this article will further break down the coping mechanisms used by the female characters to survive

Price reaction of ethically screened stocks: a study of the Dow Jones Islamic Market World Index

This paper investigates the short-term effects on the price of the ethically screened stocks of the Dow Jones Islamic Market World Index (DJIMWI) quarterly revisions. Using a sample of 8,250 stocks from May 1999 through June 2012, we find a significant price reaction of the ethically screened stocks following additions and deletions. The results show that additions (deletions) from emerging stock markets tend to experience a greater and significantly positive (negative) price response than additions (deletions) from the developed markets. Further tests reveal that the price reactions following DJIMWI revisions are likely to be driven by shifts in investor sentiment rather than changes in firm fundamentals

Electric Wheelchair Navigation Simulators: why, when, how?

International audienc

Underwriters' allocation with and without discretionary power: evidence from the Hong Kong IPO market

This study uses a unique and extensive data set from the Hong Kong IPO market to examine the theory of adverse selection under two distinct regulatory regimes in relation to underwriters’ discretionary power in IPO share allocation. Consistent with Rock’s (1996) theory of adverse selection in the IPO market, we show that, prior to the introduction of the clawback provision, retail (uninformed) investors were allocated more of the overpriced offerings and less of the underpriced issues. However, after the provision is implemented, retail investors have been allocated significantly more of the underpriced offerings and less of the overpriced ones. Overall, we find that allocation-adjusted initial returns for the retail investors are lower (higher) than the risk-free rate pre- (post-) clawback provision. These findings imply that the mandatory clawback provision has enhanced the fairness in IPO share allocations among different investor groups and has reduced the winner’s curse in the IPO market

Analysis of strategies to reduce thermal discomfort and natural gas consumption during heating season in Algerian residential dwellings

In the Algerian building sector, the heating needs are essentially satisfied with fossil fuels (in particular natural gas). The more common heating system in multifamily buildings is a gas heater in the central corridor of each dwelling. This system can cause important overheating in the corridor and significant gas consumption. The present study evaluates the energy savings and thermal comfort improvement, for three different cities of Algeria, achieved with a different heating system based on hot water radiators. In situ measurements were performed in a typical dwelling (which served as a reference case) and the results were used to calibrate and validate the TRNSYS model that was used for this study. A parametric analysis was performed by varying the location, heating system, envelope and windows. It was found that among the scenarios tested, it was possible to substantially reduce the heating needs compared to the reference dwelling and that the number of hours of thermal discomfort could be virtually eliminated. The most influential parameters affecting these model outputs appeared to be the wall thermal insulation