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Absence of ferroelectricity in BiMnO3 ceramics J. Appl. Phys. 112, 074112 (2012) Improved performances of polymer-based dielectric by using inorganic/organic core-shell nanoparticles Appl. Phys. Lett. 101, 142901 (2012) Spatial power combination within fan-shaped region using anisotropic zero-index metamaterials Appl. Phys. Lett. 101, 141902 (2012) The Thomas-Fermi model in the theory of systems of charged particles above the surface of liquid dielectricsThe dielectric properties of Mn x Ni 0.5Ϫx Zn 0.5 Fe 2 O 4 ferrites with x varying from 0.05 to 0.4 synthesized by the citrate precursor method have been investigated as a function of frequency, temperature, composition, and sintering temperature. An increase in the dielectric constant is observed with the increase in Mn concentration except for xϭ0.3. Dispersion in the dielectric constant with frequency in the range of 100 Hz-1 MHz is observed. Resonance peaks were observed in tan ␦ versus frequency curves for all samples. A shift in the resonance frequency towards higher frequency is observed with increase in temperature. The peak height also increases with increase in temperature. Possible mechanisms contributing to these processes have been discussed. From the temperature variation of the dielectric relaxation, activation energies for various samples have been calculated and compared with those obtained from dc resistivity.

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Part I Cell loss in rats with a normal mucosaThe concept of continuous epithelial renewal in the gastrointestinal tract was introduced at the end of the nineteenth century (Patzelt, 1882;Bizzozero, 1888;Schaffer, 1891), and since then labelling experiments with tritium-labelled thymidine have established that epithelial cells are produced in the crypts of the small intestinal mucosa, migrate up onto the villi and are lost at the tips, both in experimental animals (Leblond and Messier, 1958;Quastler and Sherman, 1959;Creamer, Shorter, and Bamforth, 1961) and in man (Shorter, Moertel, Titus, and Reitemeier, 1964;MacDonald, Trier, and Everett, 1964). It has been previously considered that epithelial cells migrate up from the mouth of the crypts directly onto villi on all sides, and it has therefore been assumed that there is an orderly one-to-one relationship of crypts to villi, with one crypt orifice between adjacent villi. In another communication (Loehry and Creamer, 1968) we have established that the crypt-villus relationship in the small intestinal mucosa is more complex than has been assumed, that overall there are many more crypts than villi, that very few of the crypts open out onto villi on all sides, and that, in most cases, much of each crypt opening is adjacent not to villi but to other crypts. The migration therefore of epithelial cells from crypts to villi cannot be a simple direct progression as might be expected from two-dimensional sections. Two possibilities exist: those cells emerging at sites where two crypts are adjacent must either be desquamated here at the crypt mouth or else be channelled round in some way onto villi. Because of this complex crypt-villus relationship it was thought necessary to undertake a reappraisal of cell migration, and, in order to establish whether cells were desquamated at the crypt mouth or channelled onto villi, to study the problem by a consideration of cell loss. METHODS AND TECHNIQUESDesquamated epithelial cells were collected from male 13 albino rats by total small intestinal perfusion. The animals were anaesthetized with intraperitoneal nembutal and the abdomen was opened by a midline incision. A length of 1 mm diameter PVC tubing was passed through the mouth into the rat's stomach, and guided through the pylorus into the fourth part of the duodenum where it was tied by a silk ligature. Another piece of PVC tubing, 4 mm in diameter, was passed through a small incision in the caecum and tied in place in the distal ileum. This cannula passed directly into a collecting bottle. It was found that this method of cannulating the small intestine prevented any significant bleeding into the lumen, and when the tubes were in position the small bowel could be perfused without contamination from the stomach, gallbladder, or pancreas. The small intestine with the cannulae was returned to the peritoneal cavity and normal saline infused via a constant flow pump at a temperature of 37°C. Perfusions were performed at a rate of 250 ml per hour after an initial washout, and hourl...

Temperature and frequency characteristics of low-loss MnZn ferrite in a wide temperature range J. Appl. Phys. 109, 106103 (2011); 10.1063/1.3583551Frequency dispersion of complex permeability in Mn-Zn and Ni-Zn spinel ferrites and their composite materials Mn x Ni 0.5Ϫx Zn 0.5 Fe 2 O 4 ferrites with xϭ0.05, 0.1, 0.2, 0.3, and 0.4, have been synthesized by the citrate precursor method and investigated for their magnetic properties. The initial relative permeability is observed to increase with increase in manganese concentration up to xϭ0.2 followed by a decrease, the maximum value being 632. An initial increase followed by a subsequent decrease of saturation magnetization with increase in x is observed. Curie temperature is observed to decrease continuously from 488 to 418°C when x increases from 0.05 to 0.4. Frequency variation of complex initial permeability indicates that resonance peak due to domain wall oscillations is at a frequency above 13 MHz. Saturation magnetization is observed to increase by about 22% when the sintering temperature is increased from 1200 to 1400°C. Initial permeability and B -H loops are observed to increase and constrict, respectively, with increase in sintering temperature.

Although haemorrhagic manifestations are common in primary thrombocythaemia, microvascular occlusive lesions often leading to peripheral gangrene are frequent and can be the sole clinical manifestation of the disease.Twenty-seven patients were followed for periods of 6 months to 14 years. The microvascular occlusive group of nine patients presented with distal gangrene of toes, a purple mottled appearance of the skin resembling lesions of livedo reticularis pain aggravated by warmth and erythromelalgia. These ischaemic lesions appearing without demonstrable arterial disease indicate a primary role of the platelets in the occlusive process. None of these patients presented with haemorrhagic symptoms but many later showed abnormal post-traumatic bleeding. The ischaemic lesions including the gangrenous toes were completely reversed by treatment and did not recur.Ten patients presented with characteristic features of primary haemorrhagic thrombocythaemia. The haemorrhagic manifestations ranged from small, recurrent and multiple ecchymoses to recurring gastro-intestinal blood loss, massive spontaneous haematoma and excessive post-operative bleeding.An asymptomatic group of six patients were diagnosed during routine investigation of other disorders. In none of them did a causal relationship seem possible. The miscellaneous group consisted of two patients with the characteristic clinical and haematological features of primary thrombocythaemia who when successfully treated, developed polycythaemia.Busulphan was shown to be effective in controlling the proliferative process in all groups.Primary thrombocythaemia is generally accepted as a member of the myeloproliferative group of disorders characterized by persistent elevation of platelet count with platelets of bizarre morphology and abnormal function. Although this syndrome may occur with chronic myeloid leukaemia, primary polycythaemia and myelofibrosis, this association is not inevitable and a number of patients present with pure-line platelet proliferation. It is well recognized that a characteristic presentation is spontaneous or post-traumatic haemorrhage-it is for this reason that it is often called haemorrhagic thrombocythaemia.

In the present day competitive market scenario, steel producers are striving for high speed continuous casting with stringent and consistent quality as well as reduced production cost. The ladle furnace (LF) is a key unit for achieving the above objectives during secondary steelmaking. Proper control of process parameters during LF processing of liquid steel is essential. The paper reports development of a model based advisory system, called ladle furnace on-line reckoner (LFOR), for the prediction and control of temperature and composition of steel in a LF. The thermal and chemistry models employed in the LFOR system are based on simplified physics, material and heat balance, and statistical analysis of plant data. The LFOR system is provided with graphical user interface (GUI) to display the predicted composition and temperature profile. The control advice displayed on the screen provides guidance for arcing and addition to achieve the target temperature and composition. The LFOR system has been commissioned at LF No. 2 of the LD2 and Slab Caster Shop of Tata Steel, Jamshedpur and is designed to meet the requirements of sequence casting as well as to optimise the energy input and cost of alloying additions. The performance of the LFOR system was analysed and validated with data taken over 100 heats and was noted to be satisfactory.

Patients with the idiopathic hypereosinophilic syndrome (HES) may develop associated skin disorders. We describe a patient who had xerosis since birth, but who first developed symptoms of aquagenic pruritus soon after he presented with HES. Photochemotherapy with psoralen and UVA treatment reduced his peripheral blood eosinophil count. The good response to treatment suggests that there was a close relationship between the dermatosis and the blood disorder.