EBSD and Nanoindentation-Correlated Study of Delamination Fracture in Al-Li Alloy 2090

Al-Li alloys offer attractive combinations of high strength and low density. However, a tendency for delamination fracture has limited their use. A better understanding of the delamination mechanisms may identify methods to control delaminations through processing modifications. A combination of new techniques has been used to evaluate delamination fracture in Al-Li alloys. Both high quality electron backscattered diffraction (EBSD) information and valid nanoindentation measurements were obtained from fractured test specimens. Correlations were drawn between nano-scale hardness variations and local texture along delaminating boundaries. Intriguing findings were observed for delamination fracture through the combined analysis of grain orientation, Taylor factor, and kernel average misorientation

Evaluation of Niobium as Candidate Electrode Material for DC High Voltage Photoelectron Guns

The field emission characteristics of niobium electrodes were compared to those of stainless steel electrodes using a DC high voltage field emission test apparatus. A total of eight electrodes were evaluated: two 304 stainless steel electrodes polished to mirror-like finish with diamond grit and six niobium electrodes (two single-crystal, two large-grain, and two fine-grain) that were chemically polished using a buffered-chemical acid solution. Upon the first application of high voltage, the best large-grain and single-crystal niobium electrodes performed better than the best stainless steel electrodes, exhibiting less field emission at comparable voltage and field strength. In all cases, field emission from electrodes (stainless steel and/or niobium) could be significantly reduced and sometimes completely eliminated, by introducing krypton gas into the vacuum chamber while the electrode was biased at high voltage. Of all the electrodes tested, a large-grain niobium electrode performed the best, exhibiting no measurable field emission (< 10 pA) at 225 kV with 20 mm cathode/anode gap, corresponding to a field strength of 18:7 MV/m

Aerobic bacteria in safe type chronic suppurative otitis media in Gezira State, Sudan

Chronic suppurative otitis media (CSOM) is a challenging disease with a high burden on society in developing countries. Information regarding CSOM in Sudanese patients is scarce. This study aimed to identify aerobic bacteria involved in CSOM and to determine their sensitivity towards commonly prescribed antibiotics. A multi-center prospective cross sectional study was conducted between June 2012 and October 2013 in private and public ENT clinics in Gezira State, Sudan. The study included 217 CSOM patients most of whom were males or had unilateral disease. The most common isolates were Staphylococcus aureus (42.6%), Klebsiella pneumoniae (14.7%), Pseudomonas aeroginosa (12.5%) and Proteus mirabilis (10.2%). The sensitivity of all isolates was highest towards gentamicin and ciprofloxacin while multiple drug resistance was prominent towards amoxyclav, cotrimoxazole, cefuroxime, cefaclor and ceftriaxone. Ciprofloxacin and gentamicin appear to be the best choices for empiric therapy in patients with CSOM. In contrast, the use of amoxyclav, cotrimoxazole, cefuroxime, cefaclor and ceftriaxone should be discouraged.Keywords: Aerobic bacteria, Chronic suppurative otitis media, Gezira State, Sudan

Psychological distress among nursing staff during COVID - 19 Period in isolation hospitals in Khartoum state at 2020

إن الضائقة النفسية وعدم القدرة على التعامل بشكل فعال مع الضغوطات والاضطرابات العاطفية الناتجة عن المواجهة الفعالة والوباء COVID-19 وضع العالم بشكل عام في موقف حرج. هذه الدراسة عبارة عن دراسة وصفية مستعرضة تهدف إلى قياس الضغط النفسي بين الممرضات والممرضين , تألف حجم العينة من 58 ممرضة و ممرض . تم جمع البيانات عبر الإنترنت من خلال استبيان فردي وتحليل البيانات بواسطة الحزمة الإحصائية للعلوم الاجتماعية (SPSS). أظهرت النتائج أن ما يقرب من ثلث المشاركين (29.3٪) كانوا على الأرجح مصابين باضطراب خفيف و (20.7٪) كانوا على الأرجح مصابين باضطراب شديد

Fabrication of Smooth SAC305 Thin Film Via Magnetron Sputtering

SAC305 (96.5 wt% Sn, 3 wt% Ag, 0.5 wt%Cu) solder is increasingly becoming popular due to its reliability good characteristics and performance in addition to the environmental concerns and regulations that restrict the use of lead in nano/microelectronic products. In nano/microelectronics, manufacturing smooth solder coatings free of defects such as voids and cracks, which can compromise joint reliability is crucial. Magnetron sputtering offers a high degree of control over film thickness and composition, resulting in films with excellent uniformity and adhesion. Despite these advantages, fabricating continuous and robust SAC305 films using magnetron sputtering remains a difficult task with limited research addressing these Challenges. To address these challenges and obtain an enhanced surface morphology property, we focus on fabricating SAC305 thin films by optimizing the magnetron sputtering parameters including sputtering power and pressure, and by using various substrates. Field emission-scanning electron microscopy imaging, energy-dispersive X-ray spectroscopy, X-ray diffraction, and atomic force microscopy were used to evaluate the quality of the thin films

Ectopic Thyroid Presenting as a Sublingual Mass in a Sudanese Girl

Although extremely rare, the presence of ectopic thyroid tissue in the sublingual region should be considered in the differential diagnosis of masses in the cervical region. Diagnosis is confirmed by Fine-needle Aspiration\Biopsy Cytology and exclusion of malignancy by histopathologic analysis of the lesion. In general, surgery should not be attemptrd before radioisotope scan is obtained as this might be the only functioning thyroid tissue. &nbsp;This is a rare case of ectopic thyroid in the sublingual region reported in a Sudanese girl; it was diagnosed after radioisotope thyroid scan and proved to be the only functioning thyroid tissue. &nbsp

Trichobezoar: Case Report and Literature Review

A bezoar is an agglomeration of food or foreign material in the intestinal tract usually noticed in ruminants. It can be classified as trichobezoar (hair) or phytobezoar (plant material). Stomach is the commonest site for bezoar formation, which may result in obstruction, gastric wall ulceration andmalnutrition. They present with abdominal pain, small bowel obstruction or malnutrition. Trichobezoars are associated with trichotillomania. This is a case report of trichobezoar in a Sudanese girl who presented with abdominal pain. This to our knowledge is the first case to be reported from Sudan.Key words: Bezoar, Trichobezoar, Trichotillomania, Sudan

The Performance of Candidates in the Examinations of the Otorhinolaryngology Specialty, Sudanese National Board of Medical Specializations

Introduction: The Otorhinolaryngology, Head and Neck Surgery Council is one of the first established councils of the Sudanese National Board of Medical Specializations (SNBMS).This report covers the fourth rotation period from 2009-2013. It is meant to be in the form of an analytical study for more objectivity and transparency and to be a model for promotion of the general performance of other councils in administrative, examination and training issues. Objectives: The main objective of this study is to analyze the trainees’ results in part 1 and part 2 (final) examinations with regard to gender and pass rates and to draw relevant indices that help in planning for training and expansion of specialist services. Materials and Methods: This is an analytical retrospective study conducted at the (SNMSB) headquarters Khartoum, Sudan during the period from January 2009- December 2012 .This study covers the fourth rotation of the scientific council for the specialty. The study included all candidates sitting for both part 1 and part 2 examinations (265). Candidates were classified according to gender and pass rates. Candidates who withdrew form the program after passing the part 1 examination were excluded. Results:&nbsp; The total number of doctors sitting for part 1 examinant was 207. Females were 118 and males were 89. Female to male ratio was 1.3:1.0. Sixty nine (69) doctors passed the examination with over all pass percentage of 33.3%. The percentage of passed candidates among females was 31% and among males was 36%. The total number for trainees sitting for the final examination was 58. Females were 23 and males were 35. Female to male ratio was 1.0: 1.5. Thirty three (33) trainees passed the examination with over all pass percentage of 56.9%. The percentage of passed trainees among females was 52.2% and among males was 60%. The annual number of doctors sitting for part 1 examination showed marked reduction from 69 in the first year to 48 in the fourth year although there was a steady increase in-between. The average annual pass rate for part 1 examination showed noticeable increase from 23% to 42% by the end of the fourth year. The annual number of trainees sitting for the final examination was fluctuating and the biggest number was in the first year. There was a minimal increase in the number of graduates.&nbsp; Conclusions: Applicants for part one examination are mostly females. Applicants numbers are generally decreasing. The pass percentages are increasing in both parts of the examination. Males performance in both part one and part two examinations is better than females. The number of graduates does not satisfy the national needs for specialist services provision and expansion