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A method for intermediate flooding and sinking simulation of a damaged floater in time domain
No full textAbstractWhen a floater such as a ship or an offshore structure is damaged in the sea, it is necessary to determine whether the floater will sink in water or not. If the floater will sink, the time to sink should be estimated to make an emergency plan. In addition, causes of the flooding should be investigated carefully. For this purpose, a method for performing intermediate flooding and sinking simulation of the damaged floater in time domain is proposed in this study. Overall process of the proposed method consists of several steps. In the first step, data of the damaged floater such as hull form and compartments are prepared. In the second step, physical characteristics of the floater such as the increased weight considering incoming water, the center of gravity, the changed buoyancy, and the center of buoyancy are calculated at every time step. In the third step, the quasi-static equilibrium position of the floater is calculated. The second and third steps are repeated until the floater reaches to sink or to be in equilibrium. As a result, the final condition of the floater can be determined. To check the feasibility of the proposed method, it is applied to a simple box problem. Finally, it is applied to intermediate flooding simulation of a barge-type damaged floater. Two cases having damaged holes of different locations are selected. As a result, it was confirmed that the floater can be in equilibrium or sink according to the damaged position. The time to be in equilibrium or the time to sink was estimated
Quantitative structure-activity relationship and molecular docking studies of a series of quinazolinonyl analogues as inhibitors of gamma amino butyric acid aminotransferase
No full textAbstractQuantitative structure-activity relationship and molecular docking studies were carried out on a series of quinazolinonyl analogues as anticonvulsant inhibitors. Density Functional Theory (DFT) quantum chemical calculation method was used to find the optimized geometry of the anticonvulsants inhibitors. Four types of molecular descriptors were used to derive a quantitative relation between anticonvulsant activity and structural properties. The relevant molecular descriptors were selected by Genetic Function Algorithm (GFA). The best model was validated and found to be statistically significant with squared correlation coefficient (R2) of 0.934, adjusted squared correlation coefficient (R2adj) value of 0.912, Leave one out (LOO) cross validation coefficient (Q2) value of 0.8695 and the external validation (R2pred) of 0.72. Docking analysis revealed that the best compound with the docking scores of −9.5kcal/mol formed hydrophobic interaction and H-bonding with amino acid residues of gamma aminobutyric acid aminotransferase (GABAAT). This research has shown that the binding affinity generated was found to be better than the commercially sold anti-epilepsy drug, vigabatrin. Also, it was found to be better than the one reported by other researcher. Our QSAR model and molecular docking results corroborate with each other and propose the directions for the design of new inhibitors with better activity against GABAAT. The present study will help in rational drug design and synthesis of new selective GABAAT inhibitors with predetermined affinity and activity and provides valuable information for the understanding of interactions between GABAAT and the anticonvulsants inhibitors
Uranium and other heavy toxic elements distribution in the drinking water samples of SW-Punjab, India
No full textAbstractIn the present investigations, Laser Fluorimetry technique has been used for the microanalysis of uranium content in drinking water samples collected from different sources like the hand pumps, tube wells of various depths from wide range of locations in the four districts of SW-Punjab, India. The purpose of this study was to investigate the uranium concentration levels of ground water being used for drinking purposes and to determine its health effects, if any, to the local population of this region. Corresponding radiological and chemical risks have also been calculated for the uranium concentrations in ground water samples. Some other heavy elements have also been analysed using the Atomic Absorption Spectrometry. In this region, uranium concentration in 498 drinking water samples has been found to vary between 0.5–579 μgl−1with an average of 73.5 μgl−1. Data analysis revealed that 338 of 498 samples had uranium concentration higher than recommended safe limit of 30 μgl−1 (WHO, 2011) while 216 samples exceeded the threshold of 60 μgl−1 recommended by AERB, DAE, India, 2004
Microbial impacts on 99mTc migration through sandstone under highly alkaline conditions relevant to radioactive waste disposal
No full textAbstractGeological disposal of intermediate level radioactive waste in the UK is planned to involve the use of cementitious materials, facilitating the formation of an alkali-disturbed zone within the host rock. The biogeochemical processes that will occur in this environment, and the extent to which they will impact on radionuclide migration, are currently poorly understood. This study investigates the impact of biogeochemical processes on the mobility of the radionuclide technetium, in column experiments designed to be representative of aspects of the alkali-disturbed zone. Results indicate that microbial processes were capable of inhibiting 99mTc migration through columns, and X-ray radiography demonstrated that extensive physical changes had occurred to the material within columns where microbiological activity had been stimulated. The utilisation of organic acids under highly alkaline conditions, generating H2 and CO2, may represent a mechanism by which microbial processes may alter the hydraulic conductivity of a geological environment. Column sediments were dominated by obligately alkaliphilic H2-oxidising bacteria, suggesting that the enrichment of these bacteria may have occurred as a result of H2 generation during organic acid metabolism. The results from these experiments show that microorganisms are able to carry out a number of processes under highly alkaline conditions that could potentially impact on the properties of the host rock surrounding a geological disposal facility for intermediate level radioactive waste
Bloqueios de nervos periféricos guiados por ultrassom em pacientes anticoagulados – série de casos
No full textResumoJustificativa e objetivosO advento da ultrassonografia trouxe inúmeros benefícios para os bloqueios de nervos periféricos. Agregou tanto segurança quanto eficácia, dada a possibilidade de visualização de estruturas neurovasculares e da agulha durante o procedimento. Apesar desses benefícios, não há consenso na literatura sobre o uso da técnica em pacientes anticoagulados ou com outros distúrbios da coagulação. Além disso, os bloqueios periféricos variam com relação à profundidade, expansibilidade e possibilidade de compressão local. Porém, poucas sociedades levam isso em consideração para elaborar suas recomendações, estabelecem um recomendação única para bloqueios periféricos, independentemente da via usada. O objetivo desta série é ampliar a discussão sobre bloqueio de nervos periféricos em pacientes anticoagulados.Relato de casosEsta série relata 9 casos de bloqueios de nervos periféricos superficiais guiados por ultrassonografia em pacientes com discrasias primárias ou secundárias. Todos os bloqueios foram feitos por anestesiologistas experientes no manejo do ultrassom, que não foram observados hematomas ou lesões neurológicas nos casos.ConclusõesA série de casos em questão ajuda a discussão sobre bloqueios periféricos superficiais e de fácil compressão local, como o axilar, interescalênico, femoral, safeno ou poplíteo, em pacientes anticoagulados, duplamente antiagregados e/ou com outros distúrbios da coagulação desde que guiados por ultrassom e feitos por anestesiologista com vasta experiência em bloqueios guiados. Entretanto, maiores séries devem ser feitas para comprovar a segurança da técnica para esses pacientes.AbstractBackground and objectivesThe advent of ultrasound has brought many benefits to peripheral nerve blocks. It includes both safety and effectiveness, given the possibility of visualizing the neurovascular structures and the needle during the procedure. Despite these benefits, there is no consensus in the literature on the use of this technique in anticoagulated patients or with other coagulation disorders. Moreover, peripheral blocks vary in depth, spreadability, and possibility of local compression. However, few societies take it into account when drawing up its recommendations, establishing a single recommendation for performing peripheral blocks, regardless of the route used. The objective of this series is to expand the discussion on peripheral nerve block in anticoagulated patients.Case reportsThis series reports 9 cases of superficial peripheral nerve blocks guided by ultrasound in patients with primary or secondary dyscrasias. All blocks were performed by experienced anesthesiologists in the management of ultrasound, and there was no bruising or neurological injuries in the cases.ConclusionsThis case series support the discussion on conducting surface peripheral nerve blocks and easy local knowledge as the axillary, interscalene, femoral, saphenous or popliteal in anticoagulated patients, on dual antiaggregation therapy and/or with other coagulation disorders, provided that guided by ultrasound and performed by an anesthesiologist with extensive experience in guided nerve blocks. However, larger series should be performed to prove the safety of the technique for these patients
Could spent nuclear fuel be considered as a non-conventional mine of critical raw materials?
No full textAbstractEach year, more than 10 thousand tons of spent fuels are discharged from nuclear power plants in the world. Heavy element nuclear fission reactions, at the origin of energy production, generate fission products of intermediary mass, some of them being considered nowadays as critical raw materials. The potential interest to treat these spent fuels in order to recycle these elements has risen recently following increasing international tensions on their supply for industry and energy. A study was carried out on the basis of the French nuclear fuel cycle scenario in order first to evaluate the inventory of such metals in spent fuel. The only elements of interest, since in significant amount, would be rare earth elements (REE) and platinum group metals (PGM). However, compare to the annual need of REE, the amount that would be recovered from spent fuels represent less than 0.01% of the annual world production. Because of the low price of these elements, there is no economic interest for such a recovery. The case of PGM, and specifically ruthenium and rhodium, is quite different. Even if a lower amount of these elements are in spent fuel, it represents 22% for Ru and 3.5% for Rh of the annual world production. The drawback is that these elements have numerous radioactive isotopes that forbid using them for industrial applications. 20–50 years of storage after separation would be necessary for ruthenium and rhodium to get a radioactivity level lower than potential clearance levels. Before any industrial use, very efficient separation processes would be required to selectively recover these elements. The physico-chemical forms of these elements in the spent fuel make the work tricky. Finally, such a use would require the official existence of a clearance level for nuclear materials as recommended by the IAEA
HIV-infected presumptive tuberculosis patients without tuberculosis: How many are eligible for antiretroviral therapy in Karnataka, India?
No full textAbstractFor certain subgroups within people living with the human immunodeficiency virus (HIV) [active tuberculosis (TB), pregnant women, children <5years old, and serodiscordant couples], the World Health Organization recommends antiretroviral therapy (ART) irrespective of CD4 count. Another subgroup which has received increased attention is “HIV-infected presumptive TB patients without TB”. In this study, we assess the proportion of HIV-infected presumptive TB patients eligible for ART in Karnataka State (population 60million), India. This was a cross-sectional analysis of data of HIV-infected presumptive TB patients diagnosed in May 2015 abstracted from national TB and HIV program records. Of 42,585 presumptive TB patients, 28,964 (68%) were tested for HIV and 2262 (8%) were HIV positive. Of the latter, 377 (17%) had active TB. Of 1885 “presumptive TB patients without active TB”, 1100 (58%) were already receiving ART. Of the remaining 785 who were not receiving ART, 617 (79%) were assessed for ART eligibility and of those, 548 (89%) were eligible for ART. About 90% of “HIV-infected presumptive TB patients without TB” were eligible for ART. This evidence supports a public health approach of starting all “HIV-infected presumptive TB patients without TB” on ART irrespective of CD4 count in line with global thinking about ‘test and treat’
Influence of transverse loading onto push-out tests with deep steel decking
No full textAbstractThis paper presents the results of 20 push-out tests on shear stud connectors, placed centrally in the ribs of 58mm and 80mm deep steel decking. The tests were designed to investigate the realistic load–slip behaviour of the shear connectors and the influence of transverse loading. The tests considered two different stud diameters and the effect of concentric and eccentric transverse loading. In addition, the influence of a second layer of reinforcement, the welding procedure and the number of shear connectors in each rib have been considered. The observed influence of these parameters on the load–slip behaviour is presented and explained with regard to material properties and load-bearing models. In addition, the test results are compared with the current analytical approaches, which are shown to be non-conservative in some cases, because the presented deck shapes were not well considered in the development and calibration of EN 1994-1-1
Quantitative data describing the impact of the flavonol rutin on in-vivo blood-glucose and fluid-intake profiles, and survival of human-amylin transgenic mice
No full textAbstractHere we provide data describing the time-course of blood-glucose and fluid-intake profiles of diabetic hemizygous human-amylin (hA) transgenic mice orally treated with rutin, and matched control mice treated with water. We employed “parametric change-point regression analysis” for investigation of differences in time-course profiles between the control and rutin-treatment groups to extract, for each animal, baseline levels of blood glucose and fluid-intake, the change-point time at which blood glucose (diabetes-onset) and fluid-intake (polydipsia-onset) accelerated away from baseline, and the rate of this acceleration. The parametric change-point regression approach applied here allowed a much more accurate determination of the exact time of onset of diabetes than do the standard diagnostic criteria. These data are related to the article entitled “Rutin suppresses human-amylin/hIAPP misfolding and oligomer formation in-vitro, and ameliorates diabetes and its impacts in human-amylin/hIAPP transgenic mice” (J.F. Aitken, K.M. Loomes, I. Riba-Garcia, R.D. Unwin, G. Prijic, A.S. Phillips, A.R.J. Phillips, D. Wu, S.D. Poppitt, K. Ding, P.E. Barran, A.W. Dowsey, G.J.S. Cooper. 2016) [1]
Solvent fractionation of rambutan (Nephelium lappaceum L.) kernel fat for production of non-hydrogenated solid fat: Influence of time and solvent type
No full textAbstractThe present study performed isothermal (25°C) solvent fractionation of rambutan (Nephelium lappaceum L.) kernel fat (RKF) to obtain the fat fraction that had melting properties comparable to a commercial hydrogenated solid fat. The effect of two fractionation parameters, holding time (12, 18 and 24h) and solvent types (acetone and ethanol), on the properties of fractionated fat were investigated. The results showed that a fractionation time increase caused an increased yield and decreased iodine value for the high melting or stearin fractions. The thermal behaviors and solid fat index (SFI) of these stearin fractions were different from the original fat, especially for stearin from acetone fractionation. The major fatty acid in this stearin fraction was arachidic acid (C20:0) consisting of more than 90%. Overall, we demonstrated that acetone fractionation of RKF at 25°C for 24h is effective for producing a solid fat fraction, which has comparable crystallizing and melting properties to commercial hydrogenated fat. The fractionated rambutan fat obtained by this process may lead to its potential use in specific food products