Climatological studies of the quasi 16-day oscillations in the mesosphere and lower thermosphere at Yamagawa (31.2° N, 130.6° E), Japan

International audienceThe 16-day wave climatology at Yamagawa (31.2° N, 130.6° E) is investigated by analyzing the mesosphere and lower thermosphere (MLT) wind data collected with the recently installed MF radar. We have utilized the continuous data gathered during the five-year period 1996?2000. The wave climatology clearly shows some seasonal variations. The period of late autumn-spring is marked with larger wave activity, with the strongest waves being observed in the winter months. The maximum amplitude observed at Yamagawa is about 20 m/s, which is comparatively larger than the amplitudes observed at mid-latitude stations. The height dependence of the 16-day wave suggests that the maximum amplitude is observed at altitudes below 80 km. The summer months are characterized with much weaker wave activity. The vertical wavelength appears to be larger in the winter months and shorter in the summer months. The present analysis again confirms that the 16-day wave is highly sensitive to the background mean winds. Eastward motion of the background winds is a more favourable condition for the 16-day wave penetration to the MLT heights. The wave features show some signs of interannual variability. Overall, the observed features of the 16-day wave at Yamagawa, which is located at the edge of the subtropical latitudes, show some correspondence with the results reported for mid-latitude stations

A Bootstrapping Approach for Generating Maximally Path-Entangled Photon States

We propose a bootstrapping approach to generation of maximally path-entangled states of photons, so called ``NOON states''. Strong atom-light interaction of cavity QED can be employed to generate NOON states with about 100 photons; which can then be used to boost the existing experimental Kerr nonlinearities based on quantum coherence effects to facilitate NOON generation with arbitrarily large number of photons all within the current experimental state of the art technology. We also offer an alternative scheme that uses an atom-cavity dispersive interaction to obtain sufficiently high Kerr-nonlinearity necessary for arbitrary NOON generation

Cystine peptides: the intramolecular antiparallel β-sheet conformation of a 20-membered cyclic peptide disulfide

A 20-membered cyclic peptide disulfide has been synthesized as a conformational model for disulfide loops of limited ring size. 1H-nmr studies at 270 MHz establish the presence of three intramolecular hydrogen bonds involving the Leu, Val, and methylamide NH groups in CDCl3. Evidence for peptide aggregation in CDCl3 is also presented. A structural transition involving loosening of the hydrogen bond formed by the Val NH group is observed upon the measured addition of (CD3)2SO to CDCl3. Hydrogen-bonding studies, together with unusually low field positions of the Cys(1) and Cys(6) CαH resonances and high JHNCαH values provide support for an intramolecular antiparallel β-sheet conformation, facilitated by a chain reversal at the Aib-Ala segment. Extensive nuclear Overhauser effect studies provide compelling evidence for the proposed conformation and also establish a type I′ β -turn at the Aib-Ala residues, the site of the chain reversal

First report on observation of abnormal creep in a Zr-2.5wt.%Nb alloy at low stresses

Low-stress creep behaviour of a two-phase Zr-2.5%Nb alloy, differently heat treated, has been investigated using helical test specimens. The phase diagram of the α (hcp) + β (bcc) alloy is characterized by the monotectoid reaction at 893 ± 10 K: β1 → (α + β2) where β1 (Zr-20Nb) and β2 (Zr-80Nb) have widely differing compositions. At the creep testing temperature, 818 K, which is close to but below the monotectoid temperature, the creep rate for samples with the equilibrium α + β2 structure has been found to be considerably higher, over an order of magnitude, than that in samples with the metastable α + β1 structure. Microstructural changes accompanying the markedly enhanced creep rate for the α + β2 structure at stresses as low as 1-4 MPa have been explained in terms of the relative stability of the β1 and the β2 phases during the creep process. An attempt has been made to elicit the likely mechanism underlying the observed enhancement of creep rate and the changes in morphology, composition and volume fraction of the β phase

Lymphoepithelial carcinoma in the maxillary sinus: a case report.

INTRODUCTION: Lymphoepithelial carcinoma of the maxillary sinus is a very rare malignancy and it can be difficult to make a pre-operative diagnosis. CASE PRESENTATION: A 72-year-old Caucasian woman presented to our facility with an isolated right-side epistaxis that had been present for three months, with the results of a computed tomography scan showing a soft tissue mass in the right maxillary sinus with an impacted tooth. The results of a transnasal endoscopic biopsy were compatible with a lymphoepithelial carcinoma, following which our patient underwent a radical excision of the mass. The final histology results revealed lymphoepithelial carcinoma of the maxillary sinus with negative assays for Epstein-Barr virus. Our patient was given post-operative external radiotherapy and has remained disease-free at three-year follow-up. CONCLUSIONS: This report details the diagnosis and management of a case of lymphoepithelial carcinoma of the maxillary sinus, which is a very rare malignant tumor with very little mention in the literature. Only a strong suspicion with systematic use of various patho-immunological tests helps to arrive at a definitive diagnosis by excluding other better-known tumors

Creep Analysis of a Variable Thickness Rotating FGM Disc using Tresca Criterion

The study investigates steady-state creep in a rotating Al-SiCp disc having different thickness profiles and reinforcement (SiCp) gradients. The disc material is assumed to creep according to threshold-stress based law and yield following Tresca criterion. The stresses and strain rates in the disc are estimated by solving the disc equilibrium equation along with creep constitutive equations. It was observed that on increasing the disc thickness gradient, the radial stress decreases towards the inner radius but increases towards the outer radius, whereas the tangential stress decreases over the entire radius. With the increase in SiCp gradient in the FGM disc, the radial stress increases significantly throughout, however, the tangential stress increases towards the inner radius but decreases towards the outer radius. The strain rates in the disc reduce significantly over the entire disc radius and become relatively uniform with the increase in either disc thickness gradient or reinforcement gradient. Thus, the composite disc having higher thickness and higher reinforcement gradients exhibits lesser distortion.Defence Science Journal, Vol. 65, No. 2, March 2015, pp.163-170, DOI:http://dx.doi.org/10.14429/dsj.65.804

Evaluation of wound healing activity of ethanolic extract of Azadirachta Indica leaves on incision and excision wound models in Wister albino rats

Background: Wound healing is complex cellular and biochemical cascade that lead to restitution of integrity and function. Recently, the traditional use of plants for wound healing has received attention by the scientific community, as traditional medicine is a source of less expensive, comprehensive medical care, especially in developing countries. Azadirachta indica (Neem) is well-known in India, as one of the most versatile medicinal plants having a wide spectrum of biological activity. Hence, this study was undertaken to evaluate the wound healing activity of the ethanolic extract of A. indica leaf in the experimentally-induced wound in rats.Methods: The healing effect produced by A. indica extract was assessed by the rate of wound contraction histopathology and skin breaking strength by using excision wound model and incision wound model in Wister albino rats. This was compared with control (soft white paraffin) and standard (1% w/w framycetin sulfate ointment). The results have been analyzed by calculating the mean values, standard deviation and compared by using student t-test.Results: The ethanol extract of leaves of A. indica significantly promoted the wound healing activity in both excision and incision wound models.Conclusion: The study revealed promising wound healing activity of ethanolic extract of A. indica and provides a scientific rationale for the traditional use in the management of wounds

IMPACT OF ALCOHOL ON PANCREAS IN ALCOHOLIC PATIENTS

Objective: Prolonged hazardous drinking can result in progressive and irreversible damage to the pancreas gland. This occurs on the background of pancreatic inflammation, acinar atrophy and, ultimately, fibrosis and can result in significant exocrine and endocrine insufficiency. Withdrawal of alcohol at an early stage may arrest the process and, even when the condition is established, may reduce the number of inflammatory episodes and allow for better control of both exocrine and endocrine insufficiencies. This study is aimed to identify the impact of alcohol on the pancreas and to educate the patient about the importance of alcohol cessation. Methods: A retrospective study was conducted in a multispecialty clinic in the gastroenterology department for a period of one month. 60 patients were involved in the study who were diagnosed with pancreatitis (acute or chronic). The data was obtained by directly communicating with the patients which consisted of demographics and social habits. Results: Among 60 patients, the male was dominant (85%) than female (15%). Majority of the patients were in the age group of 41-60 y (65%) followed by patients 2140 y of age (25%) and patients above 60 y of age (10%). Epigastric pain was the most common presenting complaint in all patients (67%) followed by vomiting (33%). Majority of the patients involved are alcoholics (60%). Conclusion: Proper attention to the health at the time of diagnosis of disease by alcohol cessation can prevent the progression of the disease and helps the patient to lead a healthy life