Modular electromagnetic railgun accelerator for high velocity impact studies.

A modular electromagnetic railgun accelerator facility named "RAFTAR" (i.e., Railgun Accelerator Facility for Technology and Research) has been commissioned and its performance has been characterized for high velocity impact testing on materials in a single-shot mode. In the first tests, RAFTAR demonstrated an acceleration of more than 1000 m/s for an 8 g solid aluminum-7075 armature projectile. The current fed was 220 kA, having a muzzle time of about 1.75 ms. It is a single pulse breech-fed rectangular bore (14 × 13 mm2) railgun, and its 1.15 m long barrel assembly consists of two parallel copper bars with an inter-gap of 13 mm that are encased within 50 mm thick high strength reinforced fiberglass sheets (Garolite G10-FR4) and bolted from both the sides. RAFTAR is powered by two capacitor bank modules that have a maximum stored energy of 160 kJ each (containing eight 178 µF/15 kV capacitors), two high power ignitron switches, and a pulse shaping inductor. To obtain consistent acceleration of the armature inside the barrel, reversal of driving current is prevented, and its pulse duration is stretched by tactical integration of the crowbar switch and bitter coil inductor in the circuit. Armature projectile velocity measurement in-bore and outside in free space was performed by the time-of-flight technique using indigenously made miniature B-dot sensors and a novel shorting-foil arrangement, respectively. The time resolved measurement of the in-bore armature evidenced a velocity-skin-effect in the high acceleration phase. There is good agreement between the experimentally measured and theoretically predicted efficiency, confirming the optimal choice of operating parameters. The conclusion summarizes important experimental findings and analyzes the underlying causes that limit the performance of railguns.

Comparative analysis of microleakage of temporary filling materials used for multivisit endodontic treatment sessions in primary teeth: an in vitro study.

PURPOSE: Coronal leakage is an important factor contributing to the failure of endodontic treatment. The use of an efficient temporary restoration between sessions of multiple-visit pulpectomies is irrefutable. Two cements have long been used in endodontics-IRM, which is a reinforced zinc oxide cement and Cavit G, a calcium sulphate based cement. The aim of this study was to compare the microleakage of nano silver containing UDMA-based cements with routinely used zinc oxide and calcium sulphate-based temporary cements in primary teeth. METHODS: Standardized access cavities of 3 × 3 mm were prepared in the sixty caries-free primary molars. The teeth were divided randomly into four groups of 14 teeth each-Group I: IRM, Group II: Cavit G, Group III: Orafil-G and Group IV: Dia-Temp. Temporary restorative materials were applied according to the manufacturer's instructions. The teeth were subjected to thermocycling and then immersed in 0.5% basic fuchsin for 24 h. The specimens were sectioned and evaluated under a digital microscope at 20× magnification and were scored for microleakage. The collected data were tabulated and subjected to statistical analysis. RESULTS: Dia-Temp presented the least microleakage values. The highest score for microleakage was shown by IRM followed by Orafil-G and Cavit-G. There was a significant difference between IRM and Diatemp groups (p value = 0.009), and among Orafil G and Diatemp groups (p value = 0.025). CONCLUSION: Among the four materials tested, Dia-Temp exhibited the best sealing ability and its use is recommended in between sessions of endodontic treatment in primary teeth.

Randomized clinical trial of laparoscopic versus open pancreatoduodenectomy for periampullary tumours.

BACKGROUND: Laparoscopic resection as an alternative to open pancreatoduodenectomy may yield short-term benefits, but has not been investigated in a randomized trial. The aim of this study was to compare laparoscopic and open pancreatoduodenectomy for short-term outcomes in a randomized trial. METHODS: Patients with periampullary cancers were randomized to either laparoscopic or open pancreatoduodenectomy. The outcomes evaluated were hospital stay (primary outcome), and blood loss, radicality of surgery, duration of operation and complication rate (secondary outcomes). RESULTS: Of 268 patients, 64 who met the eligibility criteria were randomized, 32 to each group. The median duration of postoperative hospital stay was longer for open pancreaticoduodenectomy than for laparoscopy (13 (range 6-30) versus 7 (5-52) days respectively; P = 0·001). Duration of operation was longer in the laparoscopy group. Blood loss was significantly greater in the open group (mean(s.d.) 401(46) versus 250(22) ml; P < 0·001). Number of nodes retrieved and R0 rate were similar in the two groups. There was no difference between the open and laparoscopic groups in delayed gastric emptying (7 of 32 versus 5 of 32), pancreatic fistula (6 of 32 versus 5 of 32) or postpancreatectomy haemorrhage (4 of 32 versus 3 of 32). Overall complications (defined according to the Clavien-Dindo classification) were similar (10 of 32 versus 8 of 32). There was one death in each group. CONCLUSION: Laparoscopy offered a shorter hospital stay than open pancreatoduodenectomy in this randomized trial. Registration number: NCT02081131( http://www.clinicaltrials.gov).

Evaluation and association of serum iron and ferritin levels in children with dental caries.

BACKGROUND: Iron deficiency anemia accounts for 90% of all types of anemia in the world. Although the prevalence has declined in recent years, it remains an important pediatric public health problem. Iron deficiency has also been associated with dental caries. It impairs salivary gland function causing reduced salivary secretion and buffering capacity leading to increased caries activity. AIM: The aim of the study is to explore an association between dental caries and serum levels of iron and ferritin in children aged 3-12 years. Subjectsand Methods: The study group included 120 children, hospitalized for uncomplicated medical problems. Blood reports were evaluated to determine serum iron and ferritin levels. Dental caries experience was assessed using deft index. STATISTICAL ANALYSIS USED: The collected data were tabulated and analyzed using Student's t-test and Pearson's correlation coefficient. RESULTS: Out of 120 children, 38 children showed low serum iron levels of which 31 children had dental caries and nine out of 15 children in the high serum iron level group showed dental caries. High ferritin levels were seen in three children among which two children were caries-free and only one child had a low ferritin level who also had a positive deft score. CONCLUSION: Based on the results, it was concluded that there is an inverse association between serum iron levels and dental caries whereas there is no association between serum ferritin levels and dental caries.

Oral health status of children suffering from thyroid disorders.

BACKGROUND: Thyroid dysfunction is the second most common disorder of the endocrine system that can affect any system of the body. The oral cavity can be adversely affected by either an excess or deficiency of these hormones. AIM OF THE STUDY: To assess and compare the oral health status of children suffering from thyroid disorders and healthy children. MATERIALS AND METHODS: A total of 200 children aged between 2 years and 16 years were allocated into two groups. The study group consisted of 100 children with thyroid dysfunction (hypothyroidism/hyperthyroidism), while the control group consisted of 100 healthy children. Gingival index, plaque index, DMFT (Decayed missing filled teeth Index for permanent teeth) & Dmft index (Decayed missing filled teeth Index for primary teeth) and modified developmental defects of enamel (DDE) index were recorded and data were analyzed statistically. RESULTS: Plaque and gingival scores were significantly higher in the thyroid group compared to the control group. DMFT and dmft scores were higher in the thyroid group than the control group but the difference in score was not statistically significant. Statistically significant DDE score was found in the thyroid group. Apart from increased susceptibility to caries and poor periodontal health condition, children with thyroid disorders were also found to have other oral manifestations such as macroglossia, open bite, and change in eruption pattern. CONCLUSION: Thyroid dysfunction (both hypothyroidism and hyperthyroidism) has impact on the oral health status. Children with thyroid disorders showed high prevalence of dental caries and periodontal disease compared to the control group.

Do Health Reforms Impact Cost Consciousness of Health Care Professionals? Results from a Nation-Wide Survey in the Balkans.

BACKGROUND: Serbia, as the largest market of the Western Balkans, has entered socioeconomic transition with substantial delay compared to most of Eastern Europe. Its health system reform efforts were bold during the past 15 years, but their results were inconsistent in various areas. The two waves of global recession that hit Balkan economies ultimately reflected to the financial situation of healthcare. Serious difficulties in providing accessible medical care to the citizens became a reality. A large part of the unbearable expenses actually belongs to the overt prescription of pharmaceuticals and various laboratory and imaging diagnostic procedures requested by physicians. Therefore, a broad national survey was conducted at all levels of the healthcare system hierarchy to distinguish the ability of cost containment strategies to reshape clinician's mindsets and decision-making in practice. AIMS: Assessment of healthcare professionals' judgment on economic consequences of prescribed medical interventions and evaluation of responsiveness of healthcare professionals to policy measures targeted at increasing cost-consciousness. STUDY DESIGN: Cross-sectional study. METHODS: A nationwide cross-sectional survey was conducted through a hierarchy of medical facilities across diverse geographical regions before and after policy action, from January 2010 to April 2013. In the middle of the observed period, the National Health Insurance Fund (RFZO) adopted severe cost-containment measures. Independently, pharmacoeconomic guidelines targeted at prescribers were disseminated. Administration in large hospitals and community pharmacies was forced to restrict access to high budget-impact medical care. Economic Awareness of Healthcare Professionals Questionnaire-29 (EAHPQ-29), developed in Serbian language, was used in face-to-face interviews. The questionnaire documented clinician's attitudes on: Clinical-Decision-Making-between-Alternative-Interventions (CDMAI), Quality-of-Health-Care (QHC), and Cost-Containment-Policy (CCP). The authors randomly and anonymously recruited 2000 healthcare experts, with a total of 1487 responding; after eliminating incomplete surveys, 649 participants were considered before and 651 after policy intervention. RESULTS: Dentists (1.195±0.560) had a higher mean CDMAI score compared to physicians (1.017±0.453). The surgical group compared to the internist group had a higher total EAHPQ-29 score, CCP score and CDMAI score. Policy intervention had a statistically significant negative impact on the QHC score (F=4.958; df=1; p=0.027). There was no substantial impact of policy interventions on professional behavior and judgment with regard to the CDMAI, CCP, and total EAHPQ-29 scores. CONCLUSION: Although cost savings were forcibly imposed in practice, the effects on clinical decision-making were modest. Clinicians' perceptions of quality of medical care were explained in a less effective manner due to the severely constrained resources allocated to the providers. This pioneering effort in the Balkans exposes the inefficiency of current policies to expand clinicians' cost consciousness.

Regional odontodysplasia: Report of an unusual case involving mandibular arch.

Regional odontodysplasia (RO) is a rare developmental anomaly involving both mesodermal and ectodermal components in primary or permanent dentition. It affects the maxilla and the mandible or both; however, maxilla is more commonly involved. This article reports the case of 33-month-old boy who came with the chief complaint of delayed eruption of mandibular teeth. Findings of clinical and radiographic examination were consistent with those of RO. Maxillary dentition was unaffected. Clinical and radiographic features and treatment options are discussed.

Comparative evaluation of chlorhexidine mouthrinse versus cacao bean husk extract mouthrinse as antimicrobial agents in children.

AIM: To compare the antimicrobial efficiency of chlorhexidine and cacao bean husk extract mouthrinses in children. STUDY DESIGN: A randomised comparative study which employed purpose sampling. METHODS: Study was conducted on 50 children of both sexes aged 6-10 years old. A group of 25 children were given 10 ml of 0.2% chlorhexidine mouthrinse and another 25 children were given 10 ml of 0.1% cacao bean extract mouthrinse to rinse twice daily for about 30 seconds. The salivary samples were collected from each child in Dentocult SM vials on day one (pre-rinse) and after 7 days, 1 month and 2 months. The readings were tabulated and subjected to statistical analysis. STATISTICS: Mann-Whitney test and the p-value were used for statistical analysis. RESULTS: There was significant reduction in streptococcus mutans counts in saliva at all follow-up intervals for both mouthrinse groups. However, there was no significant difference in reduction of streptococcus mutans counts in saliva, between chlorhexidine mouthrinse group and cacao bean husk extract mouthrinse group. CONCLUSION: Cacao bean husk extract mouthrinse can be used in children as an alternative to chlorhexidine mouthrinse as it has similar antimicrobial properties and evades the side-effects of the latter.

In vitro Evaluation of the Nutritive Value of Trianthema portulacastrum as a Source of Fodder for Ruminants.

Trianthema portulacastrum (common farm weed in tropical countries) contains 21.5 ± 1.2% crude protein, similar to Lucerne with relatively low structural carbohydrate (neutral detergent fibre: 43.6 ± 3.1%). The mineral profile of T. portulacastrum was well above the critical level as far as calcium (0.3%), magnesium (0.2%), iron (50 ppm), copper (8 ppm), zinc (30.0 ppm) and manganese (50 ppm), whereas the phosphorus content at 0.13 ± 0.1 % was below the critical level recommended by McDowell et al. (1983). Degradability studies in rumen stimulation technique (RUSITEC) revealed that nearly half of the dry matter in T. portulacastrum was soluble and degradable, while 69.9% of the nitrogen was insoluble but degradable. The digestible rumen degradable nitrogen and digestible un-degradable nitrogen values were 1.2% and 1.4% respectively, with the total absorbable nitrogen value of 2.5%. This study revealed that supplementation of digestible organic matter to the extent of 14.9% and phosphorus to the extent of 0.2% was suggested as a tool to exploit the full potential nutritive value of T. portulacastrum.

Intracoronary thrombolysis in patients with acute myocardial infarction: comparison of the efficacy of urokinase with streptokinase.

The efficacy of intracoronary urokinase and streptokinase were compared in 80 patients with acute myocardial infarction in a prospective, randomized, double-blind study. Urokinase was infused into the occluded coronary artery at 6000 U/min, and streptokinase was infused at 2000 U/min. Maximal duration of infusion was 2 hr. The frequency of successfully opening the artery was similar for patients receiving urokinase (27 of 45, 60%) and those receiving streptokinase (20 of 35, 57%). Fibrinogen levels after infusion were measured in 63 patients. Nineteen of 29 streptokinase recipients had fibrinogen levels less than 100 mg/dl compared with levels of two of 34 urokinase recipients (p less than .001). Five of 45 (11%) patients receiving urokinase and 10 of 35 receiving streptokinase (29%) had bleeding complications (p less than .05). Major bleeding after early coronary artery bypass surgery was more frequent in the streptokinase group (four of five compared with a similar group of patients receiving urokinase (none of five). This study demonstrates that while urokinase and streptokinase have equal intracoronary thrombolytic efficacy, patients receiving urokinase have less systemic fibrinolysis and less perioperative bleeding with early surgery than do patients receiving streptokinase.