Protective role of air potato (Dioscorea bulbifera) of yam family in myocardial ischemic reperfusion injury

Hydroalcoholic extract of Dioscorea bulbifera (DB), a yam variety called air potato, was tested for its protective effect on myocardial ischemic/reperfusion (I/R) injury in rats due to apoptosis and necrosis. Myocardial I/R injury was induced by 30 min ischemia followed by 2 h reperfusion by perfusing isolated rat hearts with Krebs Henseilet bicarbonate (KHB) buffer in a Langendorff set up. Pretreatment of DB (150 mg kg(-1) body weight) for 30 days significantly reduced myocardial infarct size and improved the ventricular function (aortic flow and coronary flow, LVDP, LVmax dp/dt). Role of DB on apoptosis was also evaluated by determining caspase 3 as well as by examining pro-apoptotic and anti-apoptotic proteins Bax and Bcl2 by Western blot analysis followed by TUNEL assay. DB also prevented I/R-mediated down regulation of survival protein Akt and HO-1. Our results indicated that Dioscorea bulbifera could ameliorate myocardial ischemia and reperfusion injury by improving ventricular function and inhibition of cardiomyocyte necrosis and apoptosis.     

Acylation of Benzene over Clay and Mesoporous Si-MCM-41 Supported InCl3, GaCl3 and ZnCl2 Catalysts

Liquid phase acylation of benzene by acyl chloride (e.g., benzoyl chloride, butyryl chloride or phenyl acetyl chloride) over InCl₃, GaCl₃ and ZnCl₂ supported on commercial clays (viz. montmorillonite-K10, montmorillonite-KSF and kaolin) or high silica mesoporous MCM-41 at 80°C has been investigated. The Mont.-K10 and Si-MCM-41 supported InCl₃ and GaCl₃ catalysts showed high activity in the acyation of benzene by benzoyl chloride even in the presence of moisture in the reaction mixture. The redox function of the supported InCl₃, GaCl₃ or ZnCl₂ catalysts seems to play a very important role in the acylation process.     

Natural products as corrosion inhibitor for metals in corrosive media — A review

The use of inhibitors for the control of corrosion of metals and alloys which are in contact with aggressive environment is an accepted practice. Large numbers of organic compounds were studied and are being studied to investigate their corrosion inhibition potential. All these studies reveal that organic compounds especially those with N, S and O showed significant inhibition efficiency. But, unfortunately most of these compounds are not only expensive but also toxic to living beings. It is needless to point out the importance of cheap, safe inhibitors of corrosion. Plant extracts have become important as an environmentally acceptable, readily available and renewable source for wide range of inhibitors. They are the rich sources of ingredients which have very high inhibition efficiency. This article gives a vivid account of natural products which are used as corrosion inhibitors for various metal and alloys in aggressive media.     

Development of an integrated hardware and software platform for the rapid detection of cerebral aneurysm rupture

A cerebral aneurysm is defined as a weakened portion of an artery in the brain. Rupture of a cerebral aneurysm leads to subarachnoid hemorrhage (SAH). A significant number of patients with SAH are initially misdiagnosed and subjected to the risks associated with aneurysm re-rupture. Traditional detection methods recommended by physicians include computed tomography (CT) scan, lumbar puncture and angiography. Unfortunately, the CT scan is ineffective after 12 h, and angiography is best suited for those cases of finding the aneurysm before surgery. Physicians may therefore rely on lumbar puncture to develop a quick and objective evaluation by assessing xanthochromia. Bilirubin in the cerebrospinal fluid, resulting from the chemical decomposition of whole blood, is an indicator of hemorrhage. This metabolite can be detected after lumbar puncture, by differentiating its optical signature in the spinal fluid. In cases of traumatic spinal tap, bilirubin needs to be distinguished from whole blood. We introduce a diagnostic system based on visible spectroscopy to quickly and objectively assess low blood-volume SAH. The system integrates innovative hardware and a powerful software interface. We explore an algorithm that accounts for the noise and distortion from blood in the cerebrospinal fluid. We introduce a portable, user-friendly hardware platform composed of specific components designed for their sensitivity and specificity.     

Semi‐active algorithm for energy‐based predictive structural control using tuned mass dampers

A novel semi‐active control algorithm is developed and numerically evaluated for the suppression of undesirable structural vibrations. The mechanical energy of the vibrating structure is considered as the primary variable influencing the control action. This intuitive strategy is proposed to realize improved control of structural vibrations. The numerical study conducted reveals that the proposed energy‐based predictive (EBP) algorithm can be implemented on vibration control applications. The energy imparted to the structure is also reduced due to the proposed algorithm. The influence of the parameters of the proposed semi‐active tuned mass damper is studied. Further, the application of the proposed strategy on a realistic structure is numerically demonstrated by implementing the algorithm for the wind response control of a 76‐story benchmark building. The results show that the EBP algorithm is a competitive semi‐active strategy. The robustness of the strategy is also evaluated considering uncertainties in the properties of the benchmark building.     

Seismic response control of base‐isolated buildings using multiple tuned mass dampers

Seismic response of a base‐isolated building equipped with single tuned mass damper (STMD), multiple tuned mass dampers (MTMDs), and distributed multiple tuned mass dampers (d‐MTMDs) under real earthquake ground motions is investigated. Numerical study is carried out using analytical models of five‐, 10‐, and 15‐storey base‐isolated buildings equipped with the STMD, MTMDs, and d‐MTMDs. The buildings are modeled as shear‐type structure with a lateral degree of freedom at each floor level, and the buildings are isolated using the laminated rubber bearing, lead‐core rubber bearing, friction pendulum system, and resilient‐friction base isolator. The coupled differential equation of motion for the buildings are derived and solved in the incremental form using Newmark's step‐by‐step method of integration. From the numerical study conducted, it is concluded that installing a tuned mass damper at each floor level of a base‐isolated building reduces the structural response in terms of top floor acceleration and bearing displacement. It is found that installing the MTMDs and d‐MTMDs are significantly beneficial in reducing top floor acceleration as compared with the STMD. Further, almost comparable reduction in the bearing displacement could be obtained by installing the STMD, MTMDs at top, and d‐MTMDs in the base‐isolated buildings. The d‐MTMDs are more beneficial as compared with the STMD and MTMDs as otherwise huge controller mass can now be divided and distributed on different floor levels.     

Direct H2-to-H2O2 Oxidation in Aqueous Acidic Medium Containing Br Promoter Over Pd/Al2O3 and Pd/C Catalysts Thermally Pretreated Under Different Conditions

Influence of thermal pretreatments (under N₂, air or H₂ gas atmosphere at 500 °C or 700 °C) has been investigated for the Pd/Al₂O₃ and Pd/Carbon catalysts in terms of its effect on their Pd particle size and performance in the H₂-to-H₂O₂ oxidation and H₂O₂ destruction (by decomposition and/or hydrogenation) reactions in aqueous acidic medium containing Br promoter. The influence on the net H₂O₂ formation is found to depend strongly upon the catalyst support due to support–Pd cluster interactions. For both the catalysts, the thermal treatments (except in air) caused a large increase in their Pd particle size. The increase in Pd particle size caused an increase in the H₂O₂ formation activity of Pd/Al₂O₃ but a decrease in the H₂O₂ formation activity of Pd/C.     

Using knowledge generated in heuristic search for nonchronological backtracking

Problem solvers that use heuristics to guide choices often run into untenable situations that can be characterized as overconstrained. When this happens, the problem must be able to identify the right culprit from among its heuristic choices in order to avoid a potentially explosive search. In this paper, we present a solution to this for a certain class of problems where the justifications associated with choice points involve an explicit assessment of the pros and cons of choosing each alternative relative to its competitors. We have designed a problem solver that accumulates such knowledge about the pros and cons of alternative selections at choice points during heuristic search, which it updates in light of an evolving problem situation. Whenever untenable situations arise, this preserved knowledge is used to determine the most appropriate backtracking point. By endowing the backtracker with access to this domain-specific knowledge, a highly contextual approach to reasoning in backtracking situations can be achieved.     

Adsorption of reaction species for hydrogenation of o-nitrotoluene on copper chromite under catalytic conditions

Adsorption of reaction species involved in vapour phase hydrogenation of o-nitrotoluene (viz. o-nitrotoluene, o-toluidine and water) on copper chromite in presence of an inert gas (He) or hydrogen (which is one of the reactants) at temperature (473-560 K) and partial pressures at which the catalytic reaction is carried out has been investigated using the gas chromatographic pulse technique. The presence of hydrogen was found to cause a very significant decrease in the adsorption of toluidine but a little effect on the adsorption of water. The adsorption data for all the reaction species could be fitted to the Freundlich adsorption equation. The isoteric heats of adsorption obtained from the adsorption isotherm indicated that o-toluidine and water are physically absorbed, whereas o-nitrotoluene is chemisorbed on the catalyst. The heat of adsorption of water and o-nitrotoluene was found to decrease with the increase in the surface coverage, indicating repulsive interactions between the adsorbed species. On the other hand the heat of adsorption of o-toluidine (in presence or absence of H₂) was found to increase with the increase in the surface coverage, suggesting attractive interactions between the absorbed species.     

Ruptured sinus of Valsalva aneurysm simulating endocarditis

OBJECTIVE: To report on a patient with Wilms' tumor treated by partial nephrectomy with 31 years survival. METHODS: Herein we describe a 33-year-old patient who had undergone surgery for a right renal tumor at age 2 years and 10 months. A partial nephrectomy was performed because the patient had left ureterohydronephrosis. Histological analysis of the surgical specimen disclosed a nephroblastoma or Wilms' tumor. RESULTS/CONCLUSIONS: The progressive deterioration of the left urinary tract, despite attempts to correct this condition, warranted its complete suppression. The patient has remained symptom-free and leads an active social and working life 31 years after the first operation, which makes this an exceptional case in the world literature.