Structure, optical properties, TD-DFT simulations for nanosecond and continuous laser irradiation of vanadium antimony borate glass doped with nickel ferrite.

Borate antimony glass doped with vanadium oxide V2O5 encoded into a [BSV glass system] was prepared with the traditional melt quenching technique. The Nickel ferrite [NiFe2O4] was prepared using Flash auto-combustion and mixed at a fixed ratio of 0.05 gm into the glass matrix to form a BSV- composite glass system [BSV / NiFe2O4], which was also prepared using the traditional melt quenching technique. The X-Ray diffraction pattern was used to characterize the glass samples and indicated their amorphous structure, with different structure phases for different levels of V2O5 content. Ranging from 200 to 1100 nm, UV-Vis spectroscopy was used to study the optical properties of the samples. The glass was found to absorb electromagnetic waves with wavelengths lower than 500 nm, while the energy gap decreased from 2.46 eV for 0.1 mol% V2O5 to 2.39 eV for 0.5 wt% V2O5. The Urbach energy also had the same behavior, and decreasing from 0.226 to 0.217 eV. On the other hand, the refractive index increased when V2O5 was added. The thermal characteristics of a [BSV / NiFe2O4] system, such as, glass transition temperature [Formula: see text], onset temperature [Formula: see text], crystallization temperature [Formula: see text] and melting temperature [Formula: see text] were studied using a Differential Scanning Calorimeter. Using continuous and pulsed laser radiation, a [BSV-0.1 V2O5 / NiFe2O4] sample was exposed to laser irradiation to observe its effect on the optical features of the glass. Laser irradiation significantly changed the absorbance spectrum, while the energy gap decreased as time increased. The pulsed laser was found to have a more power-full and uniform effect compared to continuous laser. Time-dependent density function theory was used to optimize the geometrical structure of the glass and study the effect of the formation of 4- coordinate boron atoms on its properties.

The Cholecystectomy As A Day Case (CAAD) Score: A Validated Score of Preoperative Predictors of Successful Day-Case Cholecystectomy Using the CholeS Data Set.

BACKGROUND: Day-case surgery is associated with significant patient and cost benefits. However, only 43% of cholecystectomy patients are discharged home the same day. One hypothesis is day-case cholecystectomy rates, defined as patients discharged the same day as their operation, may be improved by better assessment of patients using standard preoperative variables. METHODS: Data were extracted from a prospectively collected data set of cholecystectomy patients from 166 UK and Irish hospitals (CholeS). Cholecystectomies performed as elective procedures were divided into main (75%) and validation (25%) data sets. Preoperative predictors were identified, and a risk score of failed day case was devised using multivariate logistic regression. Receiver operating curve analysis was used to validate the score in the validation data set. RESULTS: Of the 7426 elective cholecystectomies performed, 49% of these were discharged home the same day. Same-day discharge following cholecystectomy was less likely with older patients (OR 0.18, 95% CI 0.15-0.23), higher ASA scores (OR 0.19, 95% CI 0.15-0.23), complicated cholelithiasis (OR 0.38, 95% CI 0.31 to 0.48), male gender (OR 0.66, 95% CI 0.58-0.74), previous acute gallstone-related admissions (OR 0.54, 95% CI 0.48-0.60) and preoperative endoscopic intervention (OR 0.40, 95% CI 0.34-0.47). The CAAD score was developed using these variables. When applied to the validation subgroup, a CAAD score of ≤5 was associated with 80.8% successful day-case cholecystectomy compared with 19.2% associated with a CAAD score >5 (p < 0.001). CONCLUSIONS: The CAAD score which utilises data readily available from clinic letters and electronic sources can predict same-day discharges following cholecystectomy.

Uranium content in groundwater by laser fluorimetry; method validation and dose assessment.

In this study, the total uranium concentration was determined in groundwater samples used for irrigation and/or drinking purposes and collected from private wells in Al Sharqiya region, Saudi Arabia. The uranium concentrations were measured by laser fluorimetry preceded by radiochemical treatment to eliminate the quenching effect due to the high total dissolved solids content in the groundwater samples. For method validation, some of the measured samples were analyzed for uranium isotopic activities and measured by alpha spectrometry. The results of the uranium concentrations obtained by laser fluorimetry and alpha spectrometry were in good agreement. The uranium concentrations in all the samples were below the World Health Organization (WHO) recommended limit of 30 µg L-1. Two different approaches were followed to assess the annual effective dose from the ingestion of uranium in the analyzed groundwater samples. The annual effective doses determined by the two approaches were found to be in agreement, and varied from 2.9 to 10.2 µSv y-1, with a mean value of 6.1 µSv y-1, which is far below the WHO recommended level of 100 µSv/y. The modified laser fluorimetric procedure was found to be a good tool compared with other techniques for direct measurement of uranium concentrations in high total dissolved solids groundwater samples at low levels.

Assessment of natural radioactivity and (137)Cs in some coastal areas of the Saudi Arabian gulf.

The levels of natural radioactivity have been investigated in some Saudi Arabian Gulf coastal areas. Sampling sites were chosen according to the presence of nearby non-nuclear industrial activities such as, the two main water desalination plants in Al Khobar and Al Jubail, and Maaden phosphate complex in Ras Al Khair, to ensure that effluents discharges into the Arabian Gulf didn't enhance radioactivity in seawater and shore sediments. Seawater samples were analyzed for radium isotopes (Ra-226 & Ra-228) and measured by gamma spectrometry using high purity germanium detector, after radiochemical separation of the isotopes by co-precipitation with MnO2. Shore sediment samples were analyzed for (226)Ra, (228)Ra ((232)Th), (4)°K and (137)Cs using gamma sepectrometry. A small variation was observed in the activity concentrations of the investigated radioisotopes, and the activity levels were comparable to those reported in literature. Quality assurance and methods validation were established through the efficiency calibration of the detectors, the estimation of uncertainties, the use of blanks, the analysis of standard reference materials and the intercomparison and proficiency tests. Radiological hazards were assessed, and the annual effective dose had an average value of 0.02 mSv. On the basis of the current results, we may conclude that any radiological hazards to the public visiting these shores are not expected.

Executive summary and conclusions from the European Hydration Institute Expert Conference on human hydration, health, and performance.

On April 7-8, 2014, the European Hydration Institute hosted a small group of experts at Castle Combe Manor House, United Kingdom, to discuss a range of issues related to human hydration, health, and performance. The meeting included 18 recognized experts who brought a wealth of experience and knowledge to the topics under review. Eight selected topics were addressed, with the key issues being briefly presented before an in-depth discussion. Presented here is the executive summary and conclusions from this meeting.

Inhibition of Salmonella typhi growth using extremely low frequency electromagnetic (ELF-EM) waves at resonance frequency.

AIMS: Typhoid is a serious disease difficult to be treated with conventional drugs. The aim of this study was to demonstrate a new method for the control of Salmonella typhi growth, through the interference with the bioelectric signals generated from the microbe during cell division by extremely low frequency electromagnetic waves (ELF-EMW-ELF-EM) at resonance frequency. METHODS AND RESULTS: Isolated Salmonella typhi was subjected to square amplitude modulated waves (QAMW) with different modulation frequencies from two generators with constant carrier frequency of 10 MHz, amplitude of 10 Vpp, modulating depth ± 2 Vpp and constant field strength of 200 V m(-1) at 37°C. Both the control and exposed samples were incubated at the same conditions during the experiment. The results showed that there was highly significant inhibition effect for Salm. typhi exposed to 0·8 Hz QAMW for a single exposure for 75 min. Dielectric relaxation, TEM and DNA results indicated highly significant changes in the molecular structure of the DNA and cellular membrane resulting from the exposure to the inhibiting EM waves. CONCLUSIONS: It was concluded that finding out the inhibiting resonance frequency of ELF-EM waves that deteriorates Salm. typhi growth will be promising method for the treatment of Salm. typhi infection either in vivo or in vitro. SIGNIFICANCE AND IMPACT OF THE STUDY: This new non-invasive technique for treatment of bacterial infections is of considerable interest for the use in medical and biotechnological applications.

Endoscopic management of paediatric antrochoanal polyp: our experience.

Antrochoanal polyp is a benign polypoid lesion arising from the oedematous mucosa of the maxillary sinus and extending through the maxillary ostium into the nose. In children, it constitutes 33% of all nasal polyps. Surgery is the usual treatment for antrochoanal polyps. The primary aim of treatment for antrochoanal polyp is complete removal with total clearance of the maxillary sinus. Herein, we present 36 cases of children with antrochoanal polyps (ACPs). All patients underwent preoperative radiological assessment by CT scan. All patients were subjected to uncinectomy and modified type III maxillary sinusotomy of the maxillary ostium for removal of the ACPs. Modified type III maxillary sinusotomy was performed by dilatation of the ostium of the maxillary sinus posteriorly, inferiorly and anteriorly. The most frequent presenting complaint was unilateral nasal obstruction, followed by rhinorrhoea. In 28 children, the polyps passed through the main ostium, while in 5 patients the polyp passed through the accessory ostium. In 3 children, the origin could not assessed. The antral portion of the ACP was cystic in 3 patients and polypoidal in 33 cases. Recurrence was reported in 4 patients (11.1%) that were subjected to revision endoscopic sinus surgery. The follow-up period ranged from 12 months to 5 years with a mean of 3.5 years.

Daycase hernia surgery: a missed training opportunity.

INTRODUCTION: Traditionally uncomplicated elective hernia operations were performed by surgical trainees; allowing them to develop key competencies and skills transferable to emergency hernia surgery. Daycase surgical units (DCU) are increasingly accommodating operations that traditionally contributed to operating lists in general elective theatres. We aim to assess whether DCU could help improve training in hernia surgery. SUBJECTS AND METHODS: Operative Room Information System (ORMIS) data was collected retrospectively to identify hernia operations performed at a large NHS hospital between January 2007 and 2012. Data collected included operating surgeon(s), procedure performed and procedure time (PT). Hospital coding records were used to collect data related to patient length of stay (LOS), complications, readmissions and deaths within 30 days of procedure. RESULTS: 4668 hernia operations were performed; 3063 in DCU. 91.5% (n = 2803) were open and 8.5% (n = 260) laparoscopic repairs. Trainees assisted in 24.6% (n = 752) and led 7.8% (n = 238) of cases. Overall, the mean PT for consultant led open hernia operations was 37.44 min (95% CI 36.75-38.12) and 43.07 min (95% CI 40.99-45.16) for trainees (p < 0.05). Subgroup analysis of all hernia operations performed showed no significant difference in PT between consultants and trainees when performing open bilateral inguinal, femoral, epigastric, incisional and laparoscopic hernia operations. There were no differences in LOS, readmissions and death rates within 30 days of the operation. CONCLUSIONS: DCU are an underutilised opportunity for trainees to acquire experience of hernia operations. When given the opportunity to lead hernia operations in DCU, trainees have similar PT and complication rates to consultants in many instances. Trainees should be encouraged to assist and lead hernia cases in DCU under adequate supervision to ensure appropriate competency is achieved and high standards are maintained.

Internal hernias: a brief review.

Hernias are very familiar to a core surgical trainee in the setting of clinics and the surgical assessment unit. By definition, a hernia is an abnormal protrusion of a viscus from one compartment to another. In clinic, they are visible lumps, exhibiting a cough reflex often with a well definable history making them readily identifiable. In the acute setting, they are the third commonest cause of small bowel obstruction in the developed world. Ventral and inguinal hernias account for the majority of these with only a small proportion due to internal hernias. This article aims to educate the core surgical trainee on the anatomy and distinguishing clinical features of these rare but important types of internal abdominal hernias.

Measuring T2 and T1, and imaging T2 without spin echoes.

During adiabatic excitation, the nuclear magnetization in the transverse plane is subject to T(2) (spin-spin) relaxation, depending on the pulse length τ. Here, this property is exploited in a method of measuring T(2) using the ratio of NMR signals acquired with short and long-duration self-refocusing adiabatic pulses, without spin-echoes. This Dual-τ method is implemented with B(1)-insensitive rotation (BIR-4) pulses. It is validated theoretically with Bloch equation simulations independent of flip-angle, and experimentally in phantoms. Dual-τT(2) measurements are most accurate at short T(2) where results agree with standard spin-echo measures to within 10% for T(2) ≤ 100 ms. Dual-τ MRI performed with a long 0° BIR-4 pre-pulse provides quantitative T(2) imaging of phantoms and the human foot while preserving desired contrast and functional properties of the rest of the MRI sequence. A single 0° BIR-4 pre-pulse can provide T(2) contrast-weighted MRI and serve as a "T(2)-prep" sequence with a lower B(1) requirement than prior approaches. Finally, a Tri-τ experiment is introduced in which both τ and flip-angle are varied, enabling measurement of T(2), T(1) and signal intensity in just three acquisitions if flip-angles are well-characterized. These new methods can potentially save time and simplify relaxation measurements and/or contrast-weighted NMR and MRI.