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An electronic survey of 188 acute NHS hospitals was carried out to assess the provision of out-of-hours services for gastrointestinal emergencies in England. The response rate was 167/188 (89%) for the main questionnaire and 157/188 (84%) for a supplementary questionnaire. The survey revealed that the majority of gastroenterologists (135/157, 86%) participate in acute general medicine. A rota for out-of-hours endoscopy was in place in only 82/167 (49%) of hospitals. Trained nurse endoscopy assistance was available in 51/82 (62%) of those hospitals with a formal rota. Two thirds of gastroenterologists were telephoned up to five times each month for advice when not on call; 64% felt their emergency endoscopy service provision was unsatisfactory and 38% thought it was unsafe. This paper concludes that there is serious under provision of services for patients presenting with gastrointestinal emergencies in England.

Cortisol secretion in ACTH independent bilateral macronodular adrenal hyperplasia (AIMAH) can be regulated by aberrant adrenal receptors. We describe a patient with Cushing’s syndrome (CS) due to AIMAH and concomitant Class IV congestive heart failure (CHF). Clinical testing for the presence of aberrant receptors revealed a pronounced serum cortisol (257%) and aldosterone response (212%) to the administration of ACTH and a partial serum cortisol (35%) and aldosterone (106%) response to upright posture. This suggested the possible presence of aberrant hormone receptors for ACTH [melanocortin 2 receptor (MC2-R)], vasopressin, catecholamines or angiotensin II (AT-II) on the patient’s adrenal glands. Adrenal tissue from the patient demonstrated an eight-fold increased expression of MC2-R compared to normal adrenal tissue. This increased expression was consistent with the increase in cortisol and aldosterone seen in response to exogenous ACTH. We propose that the severe CHF resulted in activation of the renin-angiotensin system, with an increased production of AT-II. The elevated circulating levels of AT-II may have led to increased expression of MC2-R on the patient’s adrenal glands and increased responsiveness to ACTH. This unusual case of CS may elucidate a heretofore unknown mechanism for the development of AIMAH.

Abstract: Bulk tube conductors of Bi 1.84 Pb 0.4 Sr 2 Ca 2.2 Cu 3 O 10+x with addition of silver varying from 0 to 25 wt% (not reported earlier) were systematically studied using X-ray diffraction (XRD), scanning electron microscopy (SEM), electrical transport and a.c. susceptibility techniques. The tube conductors formed by cold isostatic pressing (CIP) of the powders obtained from spray drying method have been made successfully. It was found that Ag addition has not only affected the formation of the desired Bi-2223 phase and the microstructure of these large bulk tube samples thereby influencing on the critical current ( I c ),it also reduces the contact resistance to minimize the cryogen losses. These variations have been found to be Ag content dependent. An optimized value of 10 wt% Ag has been found to produce the best quality tubes showing reproducible I c value > 120 Amp at 77 K which is in general a requirement to energies of the cryogen free conventional/HTSC superconducting magnets below 20 K.

CuInSeTe was synthesized by the melt and anneal technique. The compound crystallized in the chalcopyrite structure having space group I4?2dwith Z=4. Complete X-ray powder diffraction data were obtained and the unit cell parameters aand c, X-ray density and uparameter were calculated. These are a=0.5987(1) nm, c=1.1979(4) nm, Dx=5.96?103kg/m3, and u=0.2498. Atomic positions in the unit cell are proposed.? 2000 International Centre for Diffraction Data.

The uncertainty of measurement in quantitative XRF analysis by the scattered radiation method was evaluated following internationally accepted guidelines. Calculations are illustrated by taking up measurement data for the particular example of determination of the minor concentration of a heavy element analyte in a light matrix specimen. The standard uncertainty is calculated for each of the quantities on which the concentration of the analyte is considered to depend. These are then appropriately combined to obtain the combined uncertainty of measurement. This combined uncertainty is multiplied by a suitable coverage factor to give the expanded uncertainty. The coverage factor selected is such that the expanded uncertainty defines an interval about the measurement result that covers a desired fraction of the probability distribution characterized by the result and its combined uncertainty. The final result is expressed as the estimated value of the analyte concentration accompanied by the expanded uncertainty. Copyright © 1999 John Wiley & Sons, Ltd.

A new adsorption isotherm equation, log logP=C+n logv, has been developed which characterizes many properties of the structure of porous materials, such as monolayer capacity of isotherms of Types I, II and IV, limiting micropore volume at extremely low pressure, degree and dispersion of micropores, mesopore surface area, mean pore size, etc. The equation has been successfully extended to binary and ternary mixtures, data for which have been obtained from the individual isotherms. It is also shown that a linear plot of the new isotherm implies that the distribution of adsorption volume with adsorption potential is Gaussian. Various other well know isotherm equations have been deduced from this new equation. The equation is direct and involves fewer mathematical calculations for solving the structural parameters of porous materials.

Abstract: The superconducting transition temperature of the highT c compound Y1Ba2Cu3O7−x does not show degradation consequent upon the addition of metallic silver up to a concentration of 60 wt per cent. The X-ray diffraction data confirm that the oxygen deficient distorted orthorhombic perovskite structure of the pure compound stays intact as if silver does not enter the crystal lattice. SEM studies do show the presence of silver at the grain boundaries only. Silver is found to restrict the grain growth.

In this paper we report measurements of the thermoelectric power on a series of Y1Ba2Cu3O7-xspecimens with varying amounts of oxygen deficiency obtained by changing the cooling rate of the sintered specimens. The specimens have been characterized by X-ray diffraction measurements, electric resistivity and oxygen contents. The temperature variation of the thermopower reveals a peak just before the onset of superconducting transition. We examine possible theoretical explanations of this anomaly. In particular we argue that this anomaly is associated with the pairing fluctuations in the normal state close toTc. We present some theoretical results in support of this conclusion.

Gallium telluride (Ga2Te3) was synthesized at different temperatures (850 to 460° C) using different cooling rates. Materials synthesized at higher temperatures (including quenched materials from the melt) always yielded zinc-blende lattice with well resolveda1a2 doublet X-ray powder diffraction lines. In the material synthesized at lower temperature (~ 460°C), we obtained additional (superlattice) lines as reported by Newman and Cundall [4]. It was possible to index these reflections not only on an orthorhombic unit cell (a=0.417, b=2.360, c=1.252 nm) but also on cubic (a=1.7678 nm) and hexagonal (a=0.832, c=3.065 nm) unit cells. To us, the hexagonal cell appears to be more realistic. If sufficient time is given to reach equilibrium, the whole of the zinc-blende form of Ga2Te3 is transformed to the hexagonal form. It has been further observed that conversion of the hexagonal into the cubic form and vice versa can be brought about by heating the material at temperatures greater or less than 460° C, respectively. Lastly, the zinc-blende phase of Ga2Te3 is metastable and slowly transforms to hexagonal form at room temperature.

CuGa0.5In0.5Se2thin films with thickness in the range 50 to 280 nm were deposited by thermal evaporation of prereacted material on glass substrates. The films were found to be polycrystalline with single phase having chalcopyrite structure as that of bulk material. The optical constants of these films were determined by transmittance and reflectance measurements at normal incidence for light in the wavelength range 400 to 1200 nm. Three characteristic energy gaps of 1.30, 1.55 and 2.46 eV were obtained from an analysis of the optical absorption spectrum. The optical constants of the films appear to be independent of the substrate temperature.

Measurements of the Hall coefficient, dc electrical conductivity, and magnetoresistance have been made on two highly compensated, plastically bent,n-type InSb samples from liquid helium to room temperature. The number and Hall mobility of charge carriers and the electrical conductivity are greatly affected by plastic bending. The mobility decreases appreciably and the number of charge carriers increases in both the deformed samples. This increase of effective charge carriers can be attributed to the introduction of effective donor centers due to plastic bending. The electrical conductivity in one of the deformed samples increases between the temperature ranges 4.2–15 K and 125–190 K compared to that of the undeformed state of the sample. This unusual increase in s is attributed to the large increase inn value. The magnetoresistance at 4.2 K is due to impurity-band conduction and is found to be positive. It shows approximately a linear variation with magnetic field in both the deformed samples. The observed behavior of the magnetoresistance at 300 K is consistent with the behavior expected for free electrons. The observed ??/? at 77.4 K is found to be less than that at 300 K and is explained in terms of the Hall mobility values at these two temperatures.

EnhancedTcin calcium-free Tl compounds of the series TlmBa2Can−1CunOx(2201) has been reported. Three different starting compositions (2201, 1201 and 2202) were studied extensively with varying conditions of preparation. Under optimized conditions (sintering temperature 970°C and duration 3–10 min) the highestTc(onset) ranges from 103 K to ∼ 115 K andTc(zero) ∼ 95 K was found. XRD studies showed the transformation of all the three nominal compositions into 2201 phase with differentTcs.

Summary: Bovine tropical theileriosis caused byTheileria annulata is an economically important disease of cattle in India. The disease has assumed paramount importance with the intensification of cross-breeding programmes aimed at enhancing milk production in the country. To control this disease, a cell culture vaccine was developed in this department by continuous passaging ofT. annulata (Hisar) schizontsin vitro. Current work in this department has concentrated on the epidemiology of theileriosis; development of the cell culture vaccine for very young calves and pregnant cows; evaluation of serological responses using immunofluorescent antibody (IFA) tests and Enzyme-linked immunosorbent antibody assays (ELISA); studies on the duration of immunity stimulated by the cell culture vaccine; the immune/susceptible status of calves born to vaccinated dams. Results have shown the following. Clinical cases of theileriosis were mainly observed in young calves below two months of age followed by adults in exotic and cross-bred animals. Amongst indigenous animals, only young calves below two months of age suffered from clinical disease. Clinical cases of theileriosis mainly occurred between the months of April to October. TheT. annulata schizont cell culture vaccine developed in the department was extensively used in the susceptible calves and pregnant/lactating cows in the field. Sufficiently high antibody titres were detected by both schizont as well as piroplasm antigen using both ELISA and IFAT. The results indicated that the vaccine was safe, potent and effective for all breeds and age groups of cattle under field conditions. ELISA was standardised forT. annulata using three antigens,viz.: soluble piroplasm, soluble schizont and cellular schizont antigens. Comparison of results with IFAT showed that ELISA is more sensitive, objective, reliable and specific as well as less cumbersome than IFAT. Piroplasm, cellular schizont and soluble schizont antigens were found to be suitable for the detection of antitheilerial antibodies as per their order in ELISA. Studies on the duration of immunity stimulated by theT. annulata schizont cell culture vaccine indicated that immunity started waning after six months. Calves born of dams immunised againstT. annulata with the cell culture vaccine were found to be fully susceptible to theileriosis soon after birth. This indicated that there was no passive transfer of immunity from dams to their offspring through colostrum.

IntroductionInternational guidelines recommend the use of a risk stratification score for patients presenting with acute upper gastrointestinal bleeding.1The Glasgow Blatchford (GB) score is a commonly used scoring system, which was developed as an aid to predict the need for interventions such as endoscopy, blood transfusion or surgery.2The newer AIMS65 score has recently come into prominence, designed as a simpler score to predict inpatient mortality, length of stay and cost.3We therefore aim to compare both scoring systems in predicting 5 different outcomes: time to endoscopy, inpatient mortality, intensive care admission, length of stay and number of red cell units transfused.MethodThe study took place at the Whittington Hospital, a district general hospital in London, UK, over a 6 month period. Patients were screened for using medical admission lists, with information gathered from electronic and paper records. Patients’ GB and AIMS65 scores were retrospectively calculated from the clinical information available. Depending on the variable, Spearman’s Rank Correlation Coefficient or Receiver Operating Characteristic curves were used to assess the predictive characteristic of each scoring system.Results81 patients presented with acute gastrointestinal bleeding. They had a median GB score of 8 and AIMS65 score of 1. A higher GB score equated to a reduced time to endoscopy (ρ=−0.413, p=0.002), but no statistically significant trend was observed for the AIMS65 score. Both scoring systems were predictive for both length of stay and number of red cell units transfused, although AIMS65 score was superior in predicting length of stay (AIMS65 ρ=0.478, p=<0.001 versus GB ρ=0.428, p=<0.001), whereas GB score was superior in predicting number of red cell units transfused (GB ρ=0.615, p=<0.001 versus AIMS65 ρ=0.357, p=0.001). There was no statistically significant difference in predicting inpatient mortality or intensive care admission between the GB and AIMS65 scores.ConclusionAIMS65 score was superior to the GB score in predicting length of stay, consistent with published findings.4Similarly, GB score was superior to AIMS65 score in predicting the number of red cell units, consistent with a number of studies.5-7However for other outcomes the results are mixed 4-7, and more work is needed in establishing the clinical utility of these scoring systems.References. Monteiro S, et al. World J Gastrointest Pathophysiol. 2016;7(1):86–96.. Waddell KM, et al. Hosp Pract(1995).2015;43(5):290–298.. Saltzman JR, et al. Gastrointest Endosc. 2011;74(6):1215–1224.. Abougergi MS, et al. J Clin Gastroenterol. 2016;50(6):464–469.. Hyett BH, et al. Gastrointest Endosc. 2013;77(4):551–557.. Yaka E, et al. Acad Emerg Med. 2015;22(1):22–30.. Martinez-Cara JG, et al. United European Gastroenterol J. 2016;4(3):371–379.Disclosure of InterestNone Declared

High Tcsuperconductors of the nominal composition of Bi1.6Pb0.4Sr2Ca2Cu3Oywere successfully prepared by the conventional ceramic technique. The high Tcphase was predominant in all the samples giving zero resistance at 104 K. Drastic changes in density, as well as other material properties were obtained through a slight modification in the powder preparation process. Single-phase high Tcsamples with a critical current density of 1000-1200 A/cm2(at 77 K) were prepared by sintering in air for 250 h at 845°C. Most of the grains were aligned with their c-axis normal to the pellet surface.

The observation of enhanced Tcin calcium free Tl compounds Tl2Ba2Cu1Ox(2201) with varying concentration of Tl and Cu has been reported. Three different starting compositions (2201, 1201 and 2202) were studied extensively with varying conditions of preparation. Under the optimised conditions: sintering temperature 970°C and duration 3-10 minutes the highest Tc(onset) ?115 K and Tc(zero) ?95 K was found. The XRD studies showed the transformation of all the three nominal compositions into 2201 phase with different Tcs.