Simple molybdate selective oxidation catalysts containing excess MoO3 for C4 hydrocarbon oxidation to maleic anhydride

The selective oxidation of C(,4) hydrocarbons to maleic anhydride over NiMoO(,4) and CoMoO(,4) catalysts containing excess MoO(,3) was studied using a fixed bed, integral reactor system. The synthesis of pure phases and the techniques for incorporating excess MoO(,3) have been investigated. Synthesis techniques included precipitation, solid state reaction, and impregnation. Extensive characterization of the catalyst has been performed using complementary instrumentation techniques, including laser Raman spectroscopy, Raman microprobe spectroscopy, x-ray diffraction, x-ray fluorescence, x-ray photoelectron spectroscopy, scanning electron microscopy, and energy dispersive x-ray analysis. Activity and selectivity measurements were performed using these catalysts for 1-butene, 1,3-butadiene, and furan oxidation. The most selective component of the catalyst for maleic anhydride production was determined to be a MoO(,3) phase which possessed a surface covering of NiMoO(,4). NiMoO(,4) was found to have a multifunctional role in the catalytic job distribution, including catalysis of the oxidative dehydrogenation of 1-butene to 1,3-butadiene and establishment of selectivity for maleic anhydride by selectively blocking complete oxidation sites on the MoO(,3) surfaces. Post-reaction characterization by laser Raman spectroscopy, Raman microprobe spectroscopy, x-ray photo-electron spectroscopy, and scanning electron microscopy revealed that the catalyst was stable for prolonged reaction times

The new reconstruction technique in the treatment of the skin cancers located on the eyelid: Posterior temporalis fascia composite graft

BACKGROUND: Difficulty of reconstruction of the eyelids arises from the need to reconstruct different supporting and covering structures in a single operation. Defects in the anterior lamella of the eyelids can be readily repaired with skin grafts or flaps but posterior lamellar reconstruction needs more complex applications. METHODS: We performed posterior lamellar eyelid reconstruction with posterior parts of the temporalis fascia, since their anatomical and histological features are very similar to the defects. Nine patients with skin tumors located on the periorbital region were treated with local skin flaps and deep layer of the temporalis fascia. RESULTS: Grafts were harvested very easily. There was no complication related with graft or donor site. Biopsy was performed in three cases and normal conjunctival elements were seen. Functional and acceptable aesthetically results were achieved in all patients. CONCLUSION: Ideal reconstructive material for replacement of the posterior lamina is still lacking. Tarsal reconstruction can be made with deep temporalis fascia with success since the thickness of the both tissues are very similar and also since the loose areolar layer of the temporalis fascia is very thin and highly vascularized, this layer can be used in reconstruction of the conjunctiva. According to our knowledge this is the first report of using of the posterior part of temporalis fascia as a composite graft in the literature

Levitation force analysis of ring and disk shaped permanent magnet-high temperature superconductor

In superconducting magnetic levitation systems, interaction models between a high temperature superconductor and a permanent magnet are useful to analyze the dynamics of the levitated system. In this study, stiffness equations of a superconducting levitation system using a disk and a ring permanent are obtained using frozen image concept. The variation of the stiffness has been analyzed for vertical movements of the PMs. For engineering applications, accuracy of such models should be tested experimentally. An experimental PM-HTS setup has been built to verify the obtained models for different cooling height conditions. Levitation forces computed using the frozen image approach for the disk and ring PMs are converged to the experimental results when the cooling heights are smaller values

Cutaneous horns: are these lesions as innocent as they seem to be?

BACKGROUND: Cutaneous horns (cornu cutaneum) are uncommon lesions consisting of keratotic material resembling that of an animal horn. Cutaneous horn may arise from a wide range of the epidermal lesions, which may be benign, premalignant or malignant. PATIENTS AND METHODS: In this respective study, we describe our experience of eleven patients with cutaneous horn treated at our centre between January 2000 and January 2004. The clinical, pathological and treatment details were extracted from the case records. Data is presented as frequency distribution. RESULTS: There were 8 male and 3 female patients with a median age of 57 years. Most of the lesions were located on the ear, hand and scalp. Surgical resection was carried out in all the lesions. There were two cases of squamous cell carcinoma, and one case of basal cell carcinoma, other 8 cases were benign. None of the lesions recurred and no adjuvant treatment was given to any of the malignant lesions. CONCLUSION: Cutaneous horn is a clinical diagnosis that refers to a conical projection above the surface of the skin. The lesions typically occurs in sun exposed areas, particularly the face, ear, nose, forearms, and dorsum of hands. Even though our 60% of the cutaneous horns are benign possibility of skin cancer should always be kept in mind

Enhancement of Tissue Expansion by Calcium Channel Blocker: A preliminary study

BACKGROUND: Reconstruction of the defects after surgical resection of tumors is one of the important issues in surgical oncology. It is essential that the defect should be covered with a tissue quite similar to the original one and is best achieved by harvesting tissue from an area adjacent to the defect. Tissue expansion is one of the most frequently used reconstructive techniques. A number of studies evaluated blood circulation, capsule formation, tissue tolerance, histomorphological changes and complications of expander placement. However, only a few attempted to enhance tissue expansion. This study we aimed to evaluate verapamil, a calcium channel blocker, to enhance tissue expansion. MATERIAL AND METHOD: Twelve New Zealand rabbits weighing between 900 gm and 1200 gm were assigned into study and control groups. High volume expanders (100, 200 or 300 cc) were placed into the subcutaneous tissue. Rabbits in the study group received verapamil. Expanders in the control group were inflated every three days to achieve same pressure as the study group. The size of the flaps was assessed by applying pressure on tip of the flap to demonstrate the contraction. Histopathological examinations were performed. RESULTS: By administering liquid earlier and more quickly less flap retraction was observed in the study group. In the control group expanders were exposed in two rabbits while no complication occurred in the study group. Following extraction of the expanders, the flaps were elevated and less retraction was observed in the study group compared to controls. CONCLUSION: Verapamil is safe when used topically and provides less retracted flaps. It can be suggested that verapamil acts on the myofibroblasts in the capsule around tissue expanders and thus increases efficiency of the expanders

Appearance of Renal Replacement Lipomatosis on Computed Tomography : Rare pseudotumour

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N-Methyl D-Aspartic Acid (NMDA) Receptors and Depression

The monoaminergic hypothesis of depression has provided the basis for extensive research into the pathophysiology of mood disorders and has been of great significance for the development of effective antidepressants. Current antidepressant treatments not only increase serotonin and/or noradrenaline bioavailability but also originate adaptive changes increasing synaptic plasticity. Novel approaches to depression and to antidepressant therapy are now focused on intracellular targets that regulate neuroplasticity and cell survival. Accumulating evidence indicates that there is an anatomical substrate for such a devastating neuropsychiatric disease as major depression. Loss of synaptic plasticity and hippocampal atrophy appear to be prominent features of this highly prevalent disorder. A combination of genetic susceptibility and environmental factors make hippocampal neurons more vulnerable to stress. Abundant experimental evidence indicates that stress causes neuronal damage in brain regions, notably in hippocampal subfields. Stress-induced activation of glutamatergic transmission may induce neuronal cell death through excessive stimulation of N-methyl-D-aspartic acid (NMDA) receptors. Recent studies mention that the increase of nitric oxide synthesis and inflammation in major depression may contribute to neurotoxicity through NMDA receptor. Both standard antidepressants and NMDA receptor antagonists are able to prevent stress-induced neuronal damage. NMDA antagonists are effective in widely used animal models of depression and some of them appear to be effective also in the few clinical trials performed to date. We are still far from understanding the complex cellular and molecular events involved in mood disorders. There appears to be an emerging role for glutamate neurotransmission in the search for the pathogenesis of major depression. Attenuation of NMDA receptor function mechanism appears to be a promising target in the search for a more effective antidepressant therapy

Exploration of Near-Horizon CFT Duality and AdS2/CFT1AdS_2/CFT_1 in Conformal Weyl Gravity

We compute near horizon black hole entropy via the N\"other current method within the conformal Weyl gravity paradigm for vacuum and non-vacuum spacetimes. We do this, in the vacuum case, for the near horizon near extremal Kerr metric and for the non-vacuum case we couple the conformal Weyl gravity field equations to a near horizon (linear) $U(1)$ gauge potential and analyze the respective found solutions. We highlight the non-universality of black hole entropy between black hole solutions of varying symmetries, yet their congruence with Wald's entropy formula for the respective gravity theory. Finally, we implement an $AdS_2/CFT_1$ construction to compute the full asymptotic symmetry group of one of the non-vacuum conformal Weyl black holes. We do this by performing a Robinson-Wilczek two dimensional reduction, thus enabling the construction of an effective quantum theory of the remaining field content. The effective stress energy tensor generates an asymptotic Virasoro algebra, to $s$-wave approximation, whose center in conjunction with their proper regularized lowest Virasoro eigen-mode is implemented to compute black hole entropy via the statistical Cardy formula. We additionally implement quantum holomorphic fluxes (of the dual CFT) in the near horizon to compute the Hawking temperature of the respective black hole spacetime. We conclude with a discussion and outlook for future work.Comment: 20 pages, no figure

Susac’s Syndrome

We have read the interesting article by Raets and Gelin, entitled “Susac’s syndrome: a clinical and radiological challenge” which was published in the 95 (6) issue of the Journal in 2012 (1). The article included fairly important information which was very useful for us. However, we would like to make a few contributions