Experimental Investigation of Surface Roughness and Material Removal Rate in Wire EDM of Stainless Steel 304

Its unexcelled mechanical and physical properties, in addition to its biocompatibility, have made stainless steel 304 a prime candidate for a wide range of applications. Among different manufacturing techniques, electrical discharge machining (EDM) has shown high potential in processing stainless steel 304 in a controllable manner. This paper reports the results of an experimental investigation into the effect of the process parameters on the obtainable surface roughness and material removal rate of stainless steel 304, when slotted using wire EDM. A full factorial design of the experiment was followed when conducting experimental trials in which the effects of the different levels of the five process parameters; applied voltage, traverse feed, pulse-on time, pulse-off time, and current intensity were investigated. The geometry of the cut slots was characterized using the MATLAB image processing toolbox to detect the edge and precise width of the cut slot along its entire length to determine the material removal rate. In addition, the surface roughness of the side walls of the slots were characterized, and the roughness average was evaluated for the range of the process parameters being examined. The effect of the five process parameters on both responses were studied, and the results revealed that the material removal rate is significantly influenced by feed (p-value = 9.72 × 10−29), followed by current tension (p-value = 6.02 × 10−7), and voltage (p-value = 3.77 × 10−5), while the most significant parameters affecting the surface roughness are current tension (p-value = 1.89 × 10−7), followed by pulse-on time (1.602 × 10−5), and pulse-off time (0.0204). The developed regression models and associated prediction plots offer a reliable tool to predict the effect of the process parameters, and thus enable the optimizing of their effects on both responses; surface roughness and material removal rate. The results also reveal the trade-off between the effect of significant process parameters on the material removal rate and surface roughness. This points out the need for a robust multi-objective optimization technique to identify the process window for obtaining high quality surfaces while keeping the material removal rate as high as possible

AMELIORATIVE EFFECT OF CAROB AQUEOUS EXTRACT ON WATER PIPE SMOKE INDUCED-TOXICITY IN ADULT MALE ALBINO RATS

Objective: The aim of the present study was to investigate the daily effect of pre and post treatment of carob aqueous extract (600 mg/kg b. wt.); on rats exposed to were exposed to water pipe smoke (10 mg/kg; 15 minutes) for 2, 4, 6 and 8 w.Methods: Rats were divided into 6 groups; 1st group was served as a control. Rats of the 2nd group were administered amiodarone (an antiarrhythmic medication used as a model for lung toxicity) at a dose level of 30 mg/kg. The rats of 3rd and 4th groups were exposed to water pipe smoke and treated with carob extract respectively. However, the two remaining groups (5th and 6th) were the pre-and post-treatment groups with carob extract respectively.Results: Amiodarone and water pipe smoke induced a significant increase in serum alanine aminotransferase (ALT), aspartate aminotransferase (AST) and alkaline phosphatase (ALP); on the contrary, induced a significant decrease in serum total protein and albumin. In addition; serum creatinine and urea showed a significant increase; as well as; amiodarone and water pipe smoke increased the oxidative stress (malondialdehyde/glutathione; MDA/GSH) in lung tissue homogenate. While; carob extract gavage showed protective and curative effects in liver and kidney functions; in addition; it decreased MDA level and increased GSH level significantly.Conclusion: Finally, we can conclude that the carob aqueous extract treatment revealed ameliorative effects on rats were exposed to water pipe smoke

Effects of irregular antenatal care attendance in primiparas on the perinatal outcomes: a cross sectional study

Aim: Antenatal care (ANC) is a key strategy for reducing maternal and neonatal morbidity and mortality rates because adequate utilization of antenatal health care services is associated with improved maternal and neonatal health outcomes. The current study aims to identify the factors causing lack of regular attendance at ANC clinics in primiparas and to determine the effects of lack of antenatal care on perinatal outcomes. Methods: A cross sectional study was carried out at Assiut Women\u27s Health Hospital, Egypt between October 2015 and September 2016. Estimated sample size of 516 primiparous women were divided into two groups according to number of attendance to ANC clinics; women who came four visits or more were considered regular and those who came to less than four visits were considered irregular. Data was collected via a structured interview questionnaire that included personal data, obstetrical, data about current pregnancy and labor. The researcher interviewed the women within 24 hours postpartum. Results: The majority of the study sample (74.8%) had regular ANC visits while only (25.2%) had \u3c4 antenatal visits. Financial problems (44.6%) or lack of awareness about the importance of ANC (20%) were the most common reasons for irregular ANC visits. The incidence of preeclampsia and eclampsia is significantly higher in the irregular attendants (p=0.000). Similarly, preterm birth, stillbirth and low birth weight were significantly more common among irregular attendants (p=0000). Conclusion: Women with irregular antenatal care attendance are much more prone to pregnancy complications such as preeclampsia, eclampsia and anemia besides higher adverse birth outcomes including preterm birth, low birth weight and stillbirth

Prophylactic use of carvedilol to prevent ventricular dysfunction in patients with cancer treated with doxorubicin

Objective: Deterioration in ventricular function is often observed in patients treated with anthracyclines for cancer. There is a paucity of evidence on interventions that might provide cardio-protection. We investigated whether prophylactic use of carvedilol can prevent doxorubicin-induced cardiotoxicity and whether any observed effect is dose related. Methods: A prospective, randomized, double-blind study in patients treated with doxorubicin, comparing placebo (n = 38) with different doses of carvedilol [6.25 mg/day (n = 41), 12.5 mg/day (n = 38) or 25 mg/day (n = 37)]. The primary endpoint was the measured change in left ventricular ejection fraction (LVEF) from baseline to 6 months. Results: LVEF decreased from 62 ± 5% at baseline to 58 ± 7% at 6-months (p = 0.002) in patients assigned to placebo but no statistically significant changes were observed in any of the 3 carvedilol groups. At 6 months, only one of 116 patients (1%) assigned to carvedilol had an LVEF < 50% compared to four of the 38 assigned to placebo (11%), (p = 0.013). No significant differences were noted between carvedilol and placebo in terms of the development of diastolic dysfunction, clinically overt heart failure or death. Conclusions: Carvedilol might prevent deterioration in LVEF in cancer patients treated with doxorubicin. This effect may not be dose related within the studied range

Workplace Psychosocial Factors and Mental Health among a Sample of Expatriates and the Country’s Nationals Who Working at King Khalid University, Saudi Arabia

Worplace stress is the harmful physical and emotional response that occurs when there is a poor match between job demands and the capabilities, resources, or needs of the worker. Mental health is an important issue in the workplace, particularly in developing countries. This study was aimed to explore the workplace psychosocial factors and mental health among expatriates and the country’s nationals; examine the relationship between workplace psychosocial factors and mental health. . The sample was composed of 518 country's nationals and 554 expatriates teaching staff on job at King Khalid University. Two tools were used for data collection: Socio-demographic data sheet, and Copenhagen Psychosocial Questionnaire (COPSOQ). The study results indicated that Poor mental health had a strongly statistically significant positive correlation with “quantitative  demands”,” Work-family conflict”, and “Emotional demands “ in total country’s nationals and expatriates   (p<0.01). While it was a strongly statistically significant negative  correlation with “Work pace”, “Influence at work”, “Social support from colleague”, “Social support from supervisors”, “Meaning of work”, “Commitment to the workplace” “Predictability”, and  “Recognition” (p<0.01). It was concluded that country's nationals experience worse mental health than expatriates and  this  to some extent caused by exposure to psychosocial factors at work. It has indicated the importance of taking action to reduce psychosocial factors, as this would benefit both country’s nationals and expatriate workers. Key words: Expatriates , country's nationals , workplace psychosocial factors, mental health

Concurrent Acquisition of a Single Nucleotide Polymorphism in Diverse Influenza H5N1 Clade 2.2 Sub-clades

Highly pathogenic Influenza A H5N1 was first identified in Guangdong Province in 1996, followed by human cases in Hong Kong in 1997 1,2. The number of confirmed human cases now exceeds 300 and the associated Case Fatality Rate exceeds 60% 3. The genetic diversity of the serotype continues to increase. Four distinct clades or sub-clades have been linked to human cases 4-7. The gradual genetic changes identified in the sub-clades have been attributed to copy errors by viral encoded polymerases that lack an editing function, thereby resulting in antigenic drift 8. We report here the concurrent acquisition of the same polymorphism by multiple, genetically distinct, clade 2.2 sub-clades in Egypt, Russia, Kuwait, and Ghana. These changes are not easily explained by the current theory of “random mutation” through copy error, and are more easily explained by recombination with a common source. The recombination role is further supported by the high fidelity replication in swine influenza 9 and aggregation of single nucleotide polymorphisms in H5N1 clade 2.2 hemagglutinin 10

An Epidemiological and Clinical Analysis of Cutaneous Adverse Drug Reactions Seen in a Tertiary Care Outpatient Clinic in Cairo, Egypt

A cutaneous adverse drug reaction (CADR) is any undesirable change in the structure or function of the skin, its appendages, or mucous membranes caused by a drug. The frequency of CADRs is variable, with only few studies evaluating it. Our aim was to identify the clinical spectrum of CADRs and document the epidemiological data of different types of drug eruptions among Egyptian patients attending a tertiary care center. An observational hospital-based analytical study was planned for a period of six months (January-June 2015). All patients attending the outpatient Dermatology Clinic at Kasr El Aini hospital were examined to detect patients with CADRs, who were subjected to a detailed questionnaire with a detailed drug history. A skin biopsy was taken to confirm the diagnosis and to detect the type of CADRs. The primary incidence of CADRs reported in our study was 0.28% (78 patients) from a total number of 27,093 patients. The most common CADRs were SJS/TEN in 12 patients (15.3%) and lichenoid drug eruptions in 12 patients (15.3%), followed by exanthematous drug eruptions in 11 patients (14.1%) and vasculitic drug eruptions in 9 patients (11.5%). The most common drug incriminated was ibuprofen in 6 patients (7.6%), followed by penicillin in 4 patients (5.1%) and aspirin in 3 patients (3.8%). In conclusion, incidence of CADRs in our study was similar to incidence reported in different countries; however, the incidence of life-threatening reactions such as SJS/TEN was higher compared with studies conducted abroad.</p

Utilization of Some Fruits and Vegetables By-Products to Produce High Dietary Fiber Jam

The present study aimed to investigate the chemical composition, antioxidant activity, total phenolic compounds and ?-carotene of carrot peels, apple pomace, banana peels and mandarin peels and their quality in preparing jam. Mandarin and banana peels characterized by its higher crude fiber (12.16 and 5.25%) and vitamin C (68 and 16.6 mg/100g) compared to carrot peels (3.91%) and apple pomace (3.65%). Banana peels contained higher amount of magnesium, potassium, calcium and iron compared to other peels samples. Therefore, jam of banana peels characterized by its higher content in magnesium (758 mg/100g), potassium (779 mg/100g), calcium (191 mg/100g) and iron (59.15 mg/100g). Jam of apple pomace characterized by its higher phosphorus contents (220 mg/100g) followed by jam of banana peels (138 mg/100g), mandarin peels (128 mg/100g) and carrot peels (53 mg/100g). Jam of carrot peels characterized by its higher phenolics content as gallic acid equivalent (87.4 mg/100g) followed by jams of apple pomace (82.5 mg/100g), banana peels (42.7 mg/100g) and mandarin peels (34.6 mg/100g). The same trend was observed in total flavonoids as catechen equivalent (mg CAT/100g) in jams of carrot peels, apple pomace, banana peels and mandarin peels, where they were 35.9, 30.1, 23.5 and 21.7, respectively. Furthermore, jam of carrot peels had higher antioxidant activity, where its DPPH radical, had lower DPPH based IC50 (1.8 ?g/ml) while jam of apple pomace, banana peels and mandarin peels had higher DPPH based IC50 reached to 2.04, 2.21 and 3.34 µg/ml, respectively. The same trend was observed for the ?-carotene radical in tested jam samples. Hunter color parameter showed that jam of mandarin peels had highest lightness (L* = 39.8), followed by jam of carrot peels (29.46), apple pomace (18.27) and banana peels (15.19). Therefore, jam of banana peels was darker than other tested peels samples. Sensory evaluation showed that jam of apple pomace characterized by its higher taste and odor, followed by jam of mandarin peels, banana peels and carrot peels. Color of tested jam of carrot, banana or mandarin peels was darker than apple pomace jam. Also, jam of apple pomace gave higher scores in appearance and overall acceptability. Keywords: Jam – Peels – antioxidant activity – Total phenolics– Total Flavonoid

Right mini-thoracotomy versus median sternotomy for mitral valve replacement

Background: The advantages of minimally invasive mitral valve surgery over the conventional approach is still debated. This study aimed to evaluate early outcomes after mitral valve replacement (MVR) using the right mini-thoracotomy (RMT) versus median sternotomy (MS). Methods: We prospectively included 60 patients who had MVR from May 2015 to June 2017. We classified patients into two groups; Group A (n= 30) had RMT, and Group B (n= 30) had MS. Postoperative pain score, wound satisfaction, and clinical and echocardiographic outcomes were compared between both groups. Results: The mean age was 39.90 ± 12.34 years in Group A and 45.75 ± 13.10 years in Group B (p= 0.08). Preoperative and echocardiographic data showed no statistical significance difference between the groups. Group A had longer aortic cross-clamp (118.85 ± 40.56 vs. 70.75 ± 24.81 minutes, p&lt;0.001) and cardiopulmonary bypass times (186.70 ± 67.44 vs. 104.65 ± 42.60 minutes, p&lt;0.001). &nbsp;Group B had more blood loss (565 ± 344.3 vs. 241.5 ±89.16 ml/24 hours, p&lt;0.001). The median pain score was 1 (range: 1- 3) in Group A and 4 (2- 8) in Group B (p&lt;0.001), and the median wound satisfaction was 1.5 (1- 4) in Group A and 4 (1- 7) in Group B (p&lt;0.001).&nbsp; Wound infection occurred in 1 (3.3%) patient in Group A and 6 (20%) patients in Group B (p=0.04). Conclusion: Mitral valve replacement through the right mini-thoracotomy could be a safe alternative to median sternotomy. The right mini-thoracotomy was associated with longer operative times but better pain and wound satisfaction scores and lower wound infection

Markers characterizing corneal damage during aging of rat

Aging is a biological phenomenon that involves an increase of oxidative stress associated with gradual degradation of the structure and function of the cornea. Gender differences and subsequent deterioration of cornea is an interesting topic, especially yet few data are available concerning the impact of age, especially on the corneal. One hundred male and female Wistar albino rats ages 3, 6, 18, 24, and 30 months (n=10 equal for male and female) were used. At the time interval, cornea were investigated by light and transmission electron microscopy (TEM), immunohistochemistry of caspase 3 (casp3), glial fibrillar acidic protein(GFAP) and CD45 and  flow cytometry of DNA, bcl-2-like protein 4 (BAX), transforming growth factor beta (TGF-β) and Cd45 (lymphocyte common antigen). Light and TEM investigation  revealed apparent deterioration of atrophy of corneal epithelium with vesicular vacuolar degeneration, hyalinization of stromal collagen fibrils and swelling and degeneration of the endothelial lining the descemet's membrane. There was apparent loss of keratocytes within corneal stroma. Immunohistochemistry of casp 3 and CD45 were markedly increased manifesting cell damage. GFAP showed apparent reduction of innervation of corneal stroma and endothelium layer. Flow cytometry of DNA, Bax and TGF revealed increased apoptic cell death of cornea of 30M-old rats. We concluded that aging contributed to an apparent increase of cellular damage of different corneal region associated with alterations of cell markers