Biohydrogen Production From Palm Oil Mill Effluent by Anaerobic Fermentation

Biological hydrogen production was investigated using biomass in palm oil mill effluent (POME) and artificial wastewater containing 1% glucose, 0.2% yeast extract and 0.018% magnesium chloride hexahydrate under anaerobic fermentation in a batch process. Activated POME sludge and different types of composts were collected as sources of inocula for the study. The anaerobic microflora were found to produce significant amounts of hydrogen. In the study with artificial media, 500 ml batch bioreactor was used. The experiments were carried out without pH control and at different temperatures. The maximum yield of 108.4 mmol-Hz/L-med (2.01 mol- H2/mol-glucose) at the maximum evolution rate of 182 rnl/(L-med hr) was obtained with Crest compost at 400C. Hydrogen production from POME was studied using a 5-L bioreactor optimal hydrogen production was observed at 600C and a pH range of 5.5 to 6.0, the maximal hydrogen yields of 179 mrnol/L-POME and 189 rnmol/LPOME at evolution rates of 454 ml/(L-POME hr) and 421 rnl/(L-POME hr) were obtained respectively. Fed batch hydrogen production was conducted to study the reproducibility of microflora for hydrogen production from POME. Two liters of reaction medium was removed and 2 liters of fresh POME was added to the reaction medium every 24 hr (15 times) and the reproducibility of the fed batch process was checked by changing feeding time every 8 hr (10 times). A yield of 2382 1x11-Hz/ L-POME and 2419 rnl-Hz/ L-POME at maximum evolution rates of 313 ml-Hz/ (L-POME hr) and 436 ml-Hz/(L-POME hr) were obtained respectively. Moreover, when the hydrogen production from POME using rnicroflora was scaled-up to 10 L bioreactor, hydrogen yields of 140 mrnol/LPOME and 96 mrnol/L-POME at evolution rates of 361ml/(L-POME hr) and 188 ml/(L-POME hr) were obtained at pH of 5.5 and uncontrolled pH respectively. Overall, hydrogen production was accompanied with the formation of acetate and butyrate. The experimental results showed that the gas composition contained hydrogen (66-68%) and carbon dioxide (32-34%). Throughout the study, methane gas was not observed in the evolved gas mixture. It was also found that the addition of nitrogen source in the medium caused a change in the hydrogen yield.A simple model developed from Gompertz Equation was applied to estimate the hydrogen production potential (P), hydrogen production rate (R,) and lag phase time (A), based on the cumulative hydrogen production curve. This study suggests that POME is suitable for biohydrogen synthesis without addition of any other nutrients. The finding of this study was highly reliable and showed that POME has potential for biological hydrogen production

External Factors of Delay That Affect the Performance of International Construction Contractors in Kuwait

As the construction industry in Kuwait develops, the need for international contractors to handle and manage these projects rises as well. Currently, 70% of the projects in Kuwait get delayed, some by internal factors, and some by external ones. Thus, the purpose of this research is to provide a framework for international construction contractors in Kuwait regarding the external factors of delay that they might face in their projects. External factors of delay are a newly generated type of delays that represent all the delays that are beyond the contractor’s control and cannot be anticipated in the project. In this research, the most important and frequently occurring external factors of delay were extracted and discussed with 15 project management professionals to elaborate their perspectives and construct a survey to evaluate the impact and frequency of these delaying factors in the construction industry in Kuwait. This survey was distributed to 80 project management practitioners; then, the outcomes were analyzed by using the Relative Importance Index methodology to rank the effect of the examined delaying factors. Hence this research will provide international construction contractors with an illustration of the delaying factors that they should focus on and the ones they can pay less attention to them

Board gender composition and debt financing

© 2020 John Wiley & Sons, Ltd. There is a recent upsurge in calls for more women on corporate boards around the world; however, a perception of women being risk-averse that is created by lottery and gambling studies has affected women\u27s advancement in their career ladder. Our study investigates women\u27s risk averseness when they are on corporate boards in the context of a firm\u27s use of debt financing. Using a unique Australian setting, we find that women on the board have a positive association with the firm\u27s use of debt financing. This suggests that firms with women on the board are not conservative in using debt financing. Our results are robust to the use of alternative measures of gender diversity and to a series of sensitivity checks including propensity score matching, difference-in-differences and two-stage least square techniques

Tranexamic Acid Intravenous Overdose Administration in Primary Total Knee Arthroplasty: Case Report

Background: Topical application of tranexamic acid (TXA) to bleeding wound surfaces reduces blood loss in patients undergoing some major surgeries, without systemic complications. TXA decreases blood loss and, therefore, may minimize pain. Objective: To know the efficacy and safety of tranexamic acid intravenous overdose administration in primary total knee arthroplasty. Case study: We reported a 53 years old Saudi female ambulatory with no assisting aid and was not known to have any medical illnesses, presented to the orthopedic clinic complaining of bilateral knee pain and difficulty to ambulate for long distances for the last 5 years. This complain gradually worsened since last 2 years with no history of trauma prior to presentation or even after the follow up. The pain was localized at the knee joints and it was sharp in nature. The pain used to improve with rest and paracetamol intake and aggravated while standing or walking for long period of time. She was treated surgically by total knee arthroplasty, however during the operation by mistake she was given 4000 mg of tranexamic acid through IV route instead of topical application. Conclusion: Administration of 4000 mg of tranexamic acid through IV route is unusual but it seems to be safe without side effect on the patient in the early postoperative period

Boardroom gender diversity and CEO pay deviation: Australian evidence

© 2020 Accounting and Finance Association of Australia and New Zealand We study whether boardroom gender diversity affects CEO pay. Specifically, we investigate the association between boardroom gender diversity and CEO pay deviation from the optimal level of CEO pay based on firm characteristics and market performance. Using a sample of 2,288 firm-year observations for the period 2006–2014, we find that boardroom gender diversity is negatively associated with CEO pay deviation, suggesting that firms with gender-diverse boards are cautious about the consequences of CEO pay deviation (under/overpayment), and thus likely to bridge the gap between CEO actual pay and expected pay. These findings provide important insights to the global discussion on executive compensation. Our findings are robust to alternative variable specifications, propensity score matching, difference-in-differences estimations, and generalised method of moments

SACROCOCCYGEAL TERATOMA, CASE REPORT

Sacrococcygeal teratoma (SCT) is the most common tumor presenting at birth. Commonly seen in female fetuses; this case presented, more or less with the whole feature of typical sacrococcygeal teratoma

Influence of Occupational Stress (Occupational Role Stress) on Organizational Commitment: Evidence from the Banking Sector of Karachi

It is frequently observed that stress has appeared to be one of those influential factors that have critical impacts on human life; especially, the performance of a person, which is the key aspect of human life, is impacted by stress. The purpose of this research was to extend the existing body of knowledge on the relationship between occupational stress and employees’ organizational commitment into the context of banking sector of Pakistan. This qualitative study is comprise of 303 respondents The statistical techniques that were used were Exploratory factor analysis (EFA), Confirmatory factor analysis (CFA) and Structural equation modeling (SEM). Employees were analyzed for their affective commitment, continuance commitment and normative commitments. Results shows that there is a positive or significant relationship between occupational role stress and affective commitments of employees, which implied that higher score on occupational role stress prompted lower score on affective occupational commitment of the Bank representatives. It was likewise discovered that the way of association additionally influenced the relationship between occupational role stress and other two types of organizational commitments i.e. continuance and normative commitments of employees. The level of significance for employees working in banking sectors of Pakistan was found to be insignificant for continuance and for normative commitment. These results approved that there is an opposite relationship between occupational role stress and normative and continuance commitment as compared to affective job responsibility of employees