The Role of Microalgae in Renewable Energy Production: Challenges and Opportunities

Microalgae are one of the most effective sources of renewable energy production. It can grow at high rates and capable of producing oil along the year. Microalgae biomass was first suggested as a feedstock for biofuel production and received early attention for commercial application. Microalgae are expected to be a vital raw material for amino acids, vitamins and productions of valuable byproducts. The cultivation of microalgae is known to be the most gainful business in the biotechnological industry. It is a waste less, environmentally pure, energy and resource saving route. Biodiesel production from algal lipid is non-toxic and highly biodegradable. Conversion of biomass to biofuel can be achieved by different methods which are broadly classified into: thermal, chemical and biochemical methods, in addition to the large number of different agents for decomposing and hydrolysing. We can obtain the low-cost energy production from the wastewater treatment by using microalgae. Finally, biodiesel production by microalgae in Egypt is not practical at the economical level. In order to improve biodiesel fuel quality, the alga must be subjected to genetic engineering for up-regulation of fatty acid biosynthesis and/or by down-regulation of β-oxidation. Economically, the algal biomass must be processed for bio-refinery to maximize its utilization for different applications

Enhancing the Performance of Educational Systems using Efficient Opinion Mining Techniques

Governments and educational authorities around the world are emphasizing performance evaluation of educational systems. Opinion Mining (OM) has gained acceptance among experts in various regions, including the preparation space. The proposed model involves Two modules: the data preprocessing module and the opinion mining module. The main objective of our article is to enhance educational systems through the analysis of student comments, teacher comments and course comments. Furthermore, the proposed model uses a bundling task to make groups of packs for students from its comments. The datasets were 10,000 instances, 80% of which were for training and 20% for testing. The results showed that K-Means Algorithm had the best accuracy time /Sec of 0.03. The correctly classified 8,000 instances were equal to 96%, and incorrectly classified 2,000 instances were equal to 4%, Accuracy of the model is 95%, Recall is 94.8% and F-Measure is 93.7% between others algorithms. clustering and Association Rule Mining phases Algorithms namely Chi-Square test is good quality than Others Algorithms

Serum homocysteine as an early diagnostic marker of spontaneous bacterial peritonitis in patients with hepatic cirrhosis

Background: Spontaneous bacterial peritonitis (SBP) is a term used to describe acute infection of ascites, an abnormal accumulation of fluid in the abdomen, without a distinct or identifiable source of infection.Objective: This study aimed to assess serum homocysteine as a novel reliable early diagnostic marker for spontaneous bacterial peritonitis in patients with hepatic cirrhosis. As the diagnosis of SBP depends primarily on a polymorphonuclear leukocyte cell (PMN) count ≥ 250 mm3, however this method is invasive and sometimes not diagnostic. Patients and methods: This study was conducted on 50 cirrhotic patients with ascites. Patients were divided into 2 groups: Group (A) included 30 cirrhotic patients with SBP on the basis of PMN count in the ascitic fluid ≥ 250 cells/μL with or without positive ascitic fluid culture. Group (B) included 20 cirrhotic patients with ascites but without SBP (control group). Results: There was a significant difference between the two studied groups regarding C-reactive protein (CRP) (P=0.001) and erythrocyte sedimentation rate (ESR) (P=0.008). There was also significant difference between the two studied groups regarding ascitic fluid analysis parameters; as ascitic glucose and albumin were significantly lower in SBP group (P=0.002 & P=0.027, respectively) while ascitic lactate dehydrogenase (LDH) and PMN count were significantly higher in SBP group (P < 0.001, for both). Serum homocysteine was significantly higher in SBP group compared to non-SBP group (18.43 ± 6.95 vs. 12.13 ± 5.54 μmol/l; P=0.001). Serum homocysteine was significant at a cutoff level of 17.65 μmol/l with a sensitivity of 88.6% and 95.2% specificity for diagnosing SBP with an area under the curve (AUC) = 0.928.Conclusion: Serum homocysteine could serve as a convenient novel and reliable noninvasive early diagnostic marker for SBP in cirrhotic patients with ascites

Leptin Status and some Biochemical Parameters in Germ Cell Aplasia among Infertile Men in Gaza Strip

Background: Germ cell aplasia is a type of azoospermia which contains only Sertoli cells and no other cells involved in spermatogenesis. Recently leptin has been suggested to be linked to regulation of reproduction including spermatogenesis, controlling gonadotropins, testosterone secretion and directing the spermatocytes to full development to spermatids. Objective: To assess leptin status and some biochemical parameters in germ cell aplasia among infertile men in Gaza Strip. Design: Case control study. Setting: Specialized Medical Centers inGaza Strip. Study Subjects: A total of 78 infertile men with germ cell aplasia were interviewed to fill a questionnaire. Hormonal analysis (serum leptin, LH, FSH and testosterone) and biochemical analysis (serum cholesterol, triglyceride, HDL-C and LDL-C) were analyzed. Data analyzed using SPSS statistical package version 18. Seventy eight apparently healthy fertile men were served as controls. Results: The mean ages of controls and patients were 31.7 ± 3.9 and 32.8 ± 6.4 years old, respectively. Sexual history showed that problems with erection and ejaculation, and gonadal infection were significantly associated with infertility (P=0.000). Medical history revealed that Orchitis, trauma, cryptorchidism, varicocele and hormonal problems are associated with male infertility (P=0.000). In addition, exposure to thermal and chemical conditions were significantly related to infertiliy (P=0.000 and P=0.003, respectively). treatment of the antifungal Ketoconazole and the steroid were also significantly associated with infertility (P=0.000). The number of obese patients were 28 (35.9) whereas for controls were 6 (7.7%) with c2=19.338, P=0.000 indicating there was strong association between infertility and obesity. Serum leptin was significantly increased in patients compared to controls with percentage difference of 52.4% (21.2 ± 26.1 vs. 12.4 ± 7.6 ng/ml, t=2.019, P=0.047). In contrast, testosterone was significantly decreased in patients compared to controls with percentage difference of 45.5% (3.9 ± 2.8 vs. 6.2 ± 1.7 ng/ml, t=4.529, P=0.000). Serum LH and FSH were increased in patients compared to controls showing percentage differences of 100.6% and 130.5%, respectively (12.4 ± 6.7 vs. 4.1 ± 1.8 mIU/ml, t=7.460, P=0.000 and 25.7 ± 16.7 vs. 5.4 ± 2.6 mIU/ml, t=7.491, P=0.000, respectively). Serum cholesterol, triglycerides and low density lipoprotein (LDL-C) were significantly higher in patients compared to controls registering % differences of 28.8, 47.3 and 43.6, respectively (206.1 ± 45.5, 211.1 ± 129.0 and 123.4 ± 45.2 mg/dl vs. 154.2 ± 33.2, 130.3 ± 70.3 and 79.2 ± 33.6 mg/dl, P=0.000). In contrast, high density lipoprotein (HDL-C) was significantly lower in patient than in controls (40.4 ± 7.6 vs. 49.0 ± 4.0 mg/dl, % difference=19.2 and P=0.000). Leptin was negatively correlated with testosterone (r=-0.223 and P=0.049) and positively correlated with LDL-C and body mass index (BMI) (r=0.222, r=0.368 and P=0.05, P=0.001, respectively). Conclusions: Leptin play an important role in regulation of testicular function among patients with germ cell aplasia by direct action on testes by binding to specific receptor on leydig cell leading to inhibition of testosterone secretion and indirect action where it bind to specific receptor in hypothalamus and induce secretion gonadotropin releasing hormone

The Preoperative Use of Levosimendan in Patients undergoing Coronary Artery Bypass Surgery with Low Ejection Fraction

Background: Levosimendan is a calcium sensitizer with positive inotropic, vasodilatory, and cardioprotective actions. Levosimendan infusion time may affect the outcomes. Our objective was to evaluate its efficacy and safety when used before coronary artery bypass grafting (CABG) in patients with low ejection fraction. Methods: This prospective observational study included 150 CABG patients with ejection fraction ≤ 40% divided into two groups. In the Levosimendan group (n= 75), it was given preoperatively, and in the conventional group (n= 75), myocardial support was used if indicated. Results: Operative time (344±28.7 vs. 421.4±34.5 min) and cardiopulmonary bypass time (97±17.4 vs. 127.4±24.5) were significantly shorter in the Levosimendan group (P˂ 0.001, for both). Failure to wean from bypass (13 (17.3%) vs. 23 (30.7%), P=0.06) and the need for intra-aortic balloon pump (6 (8%) vs. 14 (18.7%), P= 0.06) were non significantly lower in the Levosimendan group. The mechanical ventilation duration (12±3.3 vs. 19.6±4.7 h, P= 0.04) and ICU stay (3.8±1.2 vs. 5.3±1.4 days, P ˂ 0.001) were lower with levosimendan. Mortality was non-significantly lower in the Levosimendan group (10 (13.3%) vs. 18 (24%), P= 0.09). There were no differences in atrial and ventricular arrhythmias between groups. Conclusion: The preoperative use of levosimendan could improve the outcomes in patients undergoing CABG with low ejection fraction. Levosimendan complication profile was comparable to the conventional approac

Hypovitaminosis D and Systemic Lupus Erythematous Activity and Related Neuropathy: Clinical Correlation

Background: Systemic lupus erythematosus (SLE) is a chronic multisystem autoimmune disease. Vitamin D has a modulating effect on immune responses. Hypovitaminosis D is highly prevalent in SLE patients, and it may lead to SLE activity and SLE-related neuropathy. Aim of the study: To recognize the role of serum vitamin D levels in SLE activity and also to investigate its relation to SLE-related neuropathy. Patients and Methods: the current study was a cross-sectional study performed on 100 SLE patients, who were divided into two groups, Group 1: included 50 patients with disease activity. Group II: included 50 patients without disease activity. They were tested for serum vitamin D levels, serum electrolytes, complement levels and nerve conduction. Results: Vitamin D was significantly low in group1 (median = 9.0 ng/ml) compared to the group 2 (median = 19.3 ng/ml and P-value of<0.001). Hypovitaminosis D was statistically significantly correlated with lower levels of complement (both C3 and C4) in the activity group but not in the non-activity group. Vitamin D levels were significantly associated with delayed nerve conduction in both groups, suggesting that neuropathy was linked to vitamin D level rather than SLE activity Conclusion: Hypovitaminosis D is statistically significantly correlated with SLE activity and SLE-related neuropathy

Condensation heat transfer characteristics of refrigerant R-407C in short tubes and an air conditioning condenser

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Low Serum 25-Hydroxy Vitamin D (25-OHD) and Hepatic Encephalopathy in HCV-Related Liver Cirrhosis

Background. Patients with liver cirrhosis experience a large variety of metabolic disorders associated with more hepatic decompensation. Hepatic encephalopathy (HE) is a significant complication in liver cirrhosis patients, presenting a wide spectrum of neuropsychological symptoms. A deficiency of 25-hydroxy vitamin D (25-OHD) in the general population is associated with a loss of cognitive function, dementia, and Alzheimer’s disease. Aim of the Study. Our study aims to check the relationship between low serum 25-OHD and HE in patients with HCV-related liver cirrhosis and assess its link with patient mortality. Patients and Methods. This study was observationally carried out on 100 patients with HCV-related liver cirrhosis. The patients were divided into 2 groups: Group A—included 50 HCV-related cirrhotic patients with HE, and Group B—included 50 HCV-related cirrhotic patients without HE. Assessment of disease severity using the end-stage liver disease (MELD) model and Child Turcotte Pugh (CTP) scores were done, and 25-OHD levels were measured. Comparison of vitamin D levels in different etiologies and different CTP categories was made using one-way ANOVA. Pearson’s correlation between the level of vitamin D and other biomarkers was applied. Results. There was a statistically significant Vitamin D level difference between the two groups. A lower level of vitamin D was observed in the HE group where the severe deficiency was 16%, while it was 6% in the other group and the moderate deficiency was 24% in HE group as compared to 10% in the other group. The insufficient vitamin D level represented 46% of the non-HE group while none of the HE group falls in this category. Vitamin D level was statistically higher in Grade 1 HE than in Grade 2 which is higher than in Grades 3 to 4. Vitamin D level was also significantly higher in those who improved from HE as compared to those who died. Conclusion. The lower levels of 25-OHD were associated with the higher incidence of HE in cirrhotic HCV patients. The worsening vitamin D deficiency was associated with increased severity of the liver disease, so vitamin D may be considered a prognostic factor for the severity of liver cirrhosis and high mortality rate in HE patients

Strukturierungsmethoden als Basis für die Einführung von qualitätsorientierten Leitsystemen in der textilen Prozesskette

A target of a mill leadership is to have a transparent image for all areas of function in the mill. Three main prerequisites are required for the achievement of this target: a reliable information network connecting all the departments and management levels, a clear leadership model able to indicate which data is to be shown at what time and which position and reliable process control systems to record the data necessary for the fulfilment of the characteristics required for the end product. Aim of this work is to determine the relevant product and process data as well as their optimal measuring locations. This requires a strict structuring of the complex data streams arising during the production as well as a clear mapping of the relations connecting them. Therefore, different analysis and structuring methods were evaluated, adapted and expanded for the use in the textile industry. Through the implementation of those methods, it was possible to obtain detailed system structures accompanied with detailed data and information structures. This creates the base for an efficient and function oriented implementation of process control systems in the textile industry. As a step towards the development of such a global system, a module was presented whose structure is appropriate for the entire textile field. The module was developed in the form of a database for a systematic analysis of the most significant faults which may appear during the yarn production. The achieved quality tracing through this module represents a basis for a full automatic process monitoring in the textile production chain

Analysis of agricultural production instability in the Gezira scheme

The study was conducted to measure the extent of instability and contribution of different components to change in mean production of the main crops grown in the Gezira scheme. The study used time series data covering the period before the adoption of liberalization policy (1970/71 to 1991/92) and the period after the adoption of liberalization policy (1992/93 to 2007/08). The main crops included in the study were sorghum, wheat, cotton and groundnuts. The instability of area, yield and production were determined, in addition to the analysis of different components of the sources of change in the mean production of crops. The findings of the study showed that sorghum, wheat and cotton witnessed a continuous increase in instability over the two periods, whereas there was a decrease in the instability of groundnuts production during post-liberalization period. The instability in area and yield of all crops moved in the same direction and their increasing/decreasing trend resulted in increase/decrease in instability. The decomposition analysis of sources of change in mean production of crops indicated that changes in mean yield accounted for large shares of the change in mean production of wheat and sorghum but change in mean area contributed largely in cotton and groundnuts. Furthermore, the analysis showed that changes in the variance of yield accounted for large share of changes in the variance of production for sorghum, while for wheat the large share was due to variance of area. The changes in the residual term were important in explaining the changes in the variance of production in the case of groundnuts. Programs and policies such as rehabilitation of irrigation canals, provision of inputs and strengthening the agricultural research and extension can play a vital role in achieving stability in the agricultural production in the Gezira scheme