Effect of Nano Silica De-agglomeration, and Methods of Adding Super-plasticizer on the Compressive Strength, and Workability of Nano Silica Concrete

Nowadays, nano silica appears to be one of the attractive cement substitution alternatives for researchers. Several authors have studied the physical effects of its incorporation on cement, despite of significant inconsistencies in reported results, specially workability and compressive strength of resulting concrete. This paper presents a thorough experimental investigation testing more than 16 concrete mixtures, which covers some of the main reasons of these inconsistencies. One of these problems is the method of applying the nano particles, as they are highly agglomerated, and if applied directly in a bulk composite, they often lose their high-surface area due to grain growth or unavailability of the high surface area where it matters. The presented research investigated how agglomeration can affect the compressive strength, and workability of normal strength concrete. Different methods of de-agglomeration were tested, as sonication, homogenization, and stirring. Besides, optimization of the super plasticizer's addition timing to concrete incorporating nano silica (NS) is elaborately investigated by adding the superplasticizer in different timings of addition; starting by adding NS to superplasticizer and water then applying de-agglomeration method, ending with de-agglomeration of NS alone with portion of water, then adding SP to the other portion of water before application them to the dry components. Results showed that sonication proved to be the most significant de-agglomeration method as it enhanced the gain in compressive strength of concrete by 23% by using only 1% nano silica as cement substitution. Sonication of NS also helped increasing the concrete workability significantly as a result of better dispersion of NS. As for the superplasticizer addition time, sonication of NS alone with portion of water, then adding SP to the other portion of water before application them to the concrete dry components showed a significant performance as compared to the other timings, as the compressive strength reached an increase of 26% compared to the control specimens. Keywords: Nano silica, concrete, plasticizers, agglomeration, workability, strength

Loop-mediated isothermal amplification: A rapid and simple method for detection of fluconazole resistant Candida albicans vaginitis

Background:Candidiasis is one of the most important opportunistic fungal infections. Time-saving antimicrobial susceptibility testing (AST) and molecular methods were developed to detect antimicrobial resistance. Loop-mediated isothermal amplification (LAMP) is a molecular diagnostic method performed isothermally with Bst DNA polymerase and four or six primers. Objective: Vitek identification of Candida isolates and determination of their AST were performed. However, it is time consuming; therefore, rapid and sensitive LAMP-based assay was tested as a method for phenotypic detection of resistance of Candida albicans isolates to fluconazole. Methods: Identification of Candida spp. isolated from vaginal swabs of non-pregnant women with vaginitis and minimal inhibitory concentration (MIC) values were done by Vitek2 system. Sensitive C. albicans isolates were inoculated into sabouraud´s dextrose broth without fluconazole while resistant strains were inoculated into broth with fluconazole and incubated at 37˚C. At end of 2nd, 4th and 6th h, cultures were harvested by 10 min centrifugation at 2,000 rpm and DNA was extracted by boiling. For LAMP, specific primers of C. albicans alpha-INT1 gene were used. Results: Out of 250 samples, 117 (46.8 %) were positive for Candida infections. Candida albicans isolates (57 isolates) were grouped into fluconazole-sensitive (12 isolates) and fluconazole-resistant (45 isolates). Fluconazole-resistant C. albicans could grow in presence of drug and positive LAMP reaction was obtained after a time interval similar to sensitive isolates. Conclusion: LAMP reaction allowed phenotypic detection of behavior of resistant strains in presence of antifungal agent. LAMP based evaluation of AST is superior to conventional methods and molecular detection of resistance genes

Nicorandil reduces myocardial injury and improves cardiac function in valve replacement surgery.

Background: Myocardial injury during cardiac surgery is associated with increased morbidity and mortality, and proper myocardial protection improves surgical outcomes. We aimed to study the role of preoperative nicorandil in myocardial protection during valve replacement surgery. Methods: The study included 40 patients who were randomized into two groups: control group, and nicorandil group. Preoperative, intraoperative, and postoperative data were collected. Creatine kinase- MB (CK-MB), troponin I, malondialdehyde (MDA), interleukin-6 (IL-6) and tumor necrosis factor-alpha (TNF-α) were measured 24-hours before surgery then 4, 12 and 48 hours after aortic cross-clamp removal. Results: Nicorandil significantly decreased MDA (p=0.005 and 0.036), TNF-α (p< 0.001), IL-6 (p<0.001 and 0.003) 4 and 12 hours following the removal of aortic clamp compared to the control group. Additionally, It significantly reduced CK-MB (p< 0.0001 and 0.0002) and troponin-I (p= 0.0002 and < 0.0001) 4 and 12 hours after the removal of the aortic clamp, respectively. However, there was no significant difference in MDA, TNF-α, IL-6, CK-MB, and troponin-I levels between the nicorandil and the control group after 48 hours following the removal of aortic clamping (p= 0.084; 0.64; 0.12; 0.12; 0.75; respectively). Conclusions: Nicorandil reduced myocardial injury significantly in valve replacement surgery. Nicorandil decreased CK-MB and troponin I and improved postoperative left ventricular ejection fraction

Readmission after Open Heart Surgery: Study of Predictors and Frequency

Background: Hospital readmissions after cardiac procedures are believed to be associated with higher in-hospital mortality and may predict poor outcomes. In addition high rate of readmission following discharge is associated with increased cost of care. Therefore, awareness of factors that predict increased risk for hospital readmission after cardiac surgery may improve the ability to reduce early readmission rates among this category of patients. Aim of the study; to assess predictors for hospital readmission after cardiac surgery. Design: A descriptive exploratory design was utilized in the current study. Subjects: A sample of Convenience including 115 adult male & female patients who were admitted to the cardiothoracic surgery departments at Kasr Al-Aini Hospital, Cairo University over a period of six months were recruited. Tools of data collection: Four tools were utilized to collect data pertinent to the current study: Socio-demographic/medical data sheet; Perioperative open heart surgery assessment Sheet; Hospital readmission assessment sheet; and the LACE index Scale (Lengths of hospital stay in days; Acuity of illness at the time of admission; Carlson co-morbidity score; and Emergency department visits numbers during previous six months. Results: the current study revealed that the majority of the studied sample were males, married, having an elective admission with percentages of (67.8%), (86.1%) & (87%) respectively, and nearly half of them were between 40–59 years & came from rural area in percentages of (50%) & (52.2%) respectively. Out of the 115 patients who discharged from the hospital 18 % required a second hospital and ICU readmission. Main reasons for readmissions were wound problems (42.9%), congestive heart failure (14.3%), atrial fibrillation (9.5%), pleural effusion (9.5%), renal failure (9.5%) and respiratory failure (4.8%). Binary logistic regression analysis revealed that preoperative renal failure, delayed extubation (mechanical ventilation > 8 h), re-exploration for bleeding, perioperative use of intraaortic ballon pump (IABP), postoperative dysrhythmias, postoperative heart failure and postsurgical (ICU) length of stay (> 3 day) were independent predictors for readmission. Conclusion & Recommendations: Based on findings of the current study, it can be concluded that readmission following discharge is an important adverse outcome of cardiac surgery that needs continued attempts to explore and manage the risk factors of readmission. So the study recommends identification & close monitoring of those at risk for readmission; Establishment of hot line services for providing proper consultation after hospital discharge, especially for emergent cases; and provision of surveillance units for detection of high risk patients. Keywords: Open Heart Surgery- Hospital Readmission-Predictors- Frequency

Could heart-type fatty acid binding protein predict clinical outcome in coronary artery bypass graft surgery?

Background: Detection of myocardial damage and its degree during open heart surgery were studied previously using different biomarkers. Heart fatty acid binding protein (h-FABP) was used in the diagnosis of myocardial infarction with variable results. In this study, we aimed to find the possibility of the use of this biomarker as a predictor of myocardial damage after coronary artery bypass graft (CABG) surgery. Methods: We conducted a prospective study on 47 patients who had CABG surgery. Blood samples (4 ml) were drawn from patients at 5 points: before induction of anesthesia, after aortic declamping, 1 hour after declamping, 6 hours after declamping and one day after surgery. Levels of h-FABP and creatine kinase muscle/brain (CK-MB) were estimated, and the relationship between h-FABP and operative and postoperative outcomes were recorded. Results: There were statistically significant correlations between higher levels of h-FABP measured immediately after aortic declamping and need for intra-aortic balloon (116.55 + 9.26 vs, 84.34 + 19.55 ng/ml; p= 0.022), inotropes (107.04+ 14.79 vs, 79.95 + 17.59ng/ml; p< 0.001), defibrillators (97.73 + 15.18 vs 81.59 + 20.31 ng/ml; p=0.016), and postoperative atrial fibrillation (99.94 + 17.83 vs 80.84 + 18.89ng/ml; p= 0.004). No mortality was detected in our study. h-FABP levels showed an early peak just after aortic declamping and reached baseline by postoperative day one. CK-MB peaked 1 hour after aortic declamping and remained elevated for more than 24 hours. Conclusion: h-FABP is a cardiac biomarker that could be used as a rapid indicator of ventricular dysfunction and atrial fibrillation post-CABG surgery

An integrated assessment approach for fossil groundwater quality and crop water requirements in the El-Kharga Oasis, Western Desert, Egypt

Study region: The El-Kharga Oasis in the Western Desert of Egypt is selected as the study area due to its hyberarid climate condition and water scarcity. In this region, the fossil groundwater is the main water source; therefore, preserving groundwater quality and quantity is mandatory. Study focus: This study evaluated groundwater suitability for irrigation purposes and assessed the water requirements of cultivated crops to optimize the water supply in hyperarid climate regions. In total, 79 deep groundwater samples were hydrochemically tested to determine the suitability for irrigation by assessing the key water quality parameters. Spatial distribution maps of all chemical parameters, such as pH, EC, SAR, RSC, SSP, TDS, total hardness, Na+, K+, Ca++, Mg++, Fe, Mn, Cl-, and SO4—, were developed. The FAO CROPWAT 8.0 model, based on the Penman–Monteith equation, was used to forecast agricultural water requirements for three years, 2010, 2011, and 2012. New hydrological insights for the region: The groundwater had medium salinity and low sodium in 84% of the cases. In comparison, high salinity was found in 16% of the samples, indicating that groundwater can be used for many soil types with a low risk of exchangeable sodium. Except for 15 of the 79 wells, all groundwater samples had chloride concentrations less than 100 mg/l. The sulfate ion distribution map showed a low sulfate ion content in the extreme western south. The total annual irrigation water requirements of all crops for 2010, 2011 and 2012 were 199.4, 215.1, and 231.7 million m3/year, respectively, reflecting a gradual increase of approximately 16.57 million m3/total area/year due to the expansion of the cultivated area. The analysis showed that modern irrigation systems reduced the amount of irrigation water by 32% and increased the cultivated area by 45% compared to conventional irrigation methods. Severe groundwater depletion occurred during the dry season from March to July, which exacerbated the water stress in the study region. The results confirmed that the region is under water stress. Accordingly, water conservation is urgently recommended

Patterns of Faculty Participation in the Areas of Social Responsibility

The study aimed to identify the patterns of participation of faculty members in the areas of social responsibility. To achieve the objectives of the study, the social survey method was relied on the sample. The study sample consisted of (136) faculty members in a university in the Saudi higher education sector. The questionnaire was used to collect data. Its stability coefficient was (0.830) and it was applied electronically to the study sample. The results of the study revealed that there is daily interaction between a faculty member, students and community institutions to contribute to all areas of responsibility and spread its culture, in addition to the tendency of the educational institution (the field of study) to achieve balance and harmony between its fields (teaching, community service / scientific research) so that the faculty member can participate in all the desired activities and events and adapt to the requirements of the institution and society, there are also some obstacles such as lack of funding for research and studies Common and directed by the faculty member towards the community, the imposition of routine procedures from the university that hinder the faculty member from participating in community initiatives, the lack of opportunities for community partnerships between the university and the private and public sectors of the state and NGOs

On The Accuracy and Completeness of The Record Matching Process

Abstract. Record matching or linking is one of the phases of the data quality improvement process, in which, records from different sources, are cleansed and integrated in a centralized data store to be used for various purposes. Both, earlier and recent studies in data quality and record linkage focus on various statistical models, which make strong assumptions on the probabilities of attribute errors. In this study, we evaluate different models for record linkage, which are built based on data only. We use a program that generates data with known error distributions and we train classification models, which we use to estimate the accuracy and the completeness of the record linking process. The results indicate that the automated learning techniques are adequate for this process and that both their accuracy and their completeness are comparable to the accuracy and the completeness of other, mostly manual, processes