Compare Inverse Matrix Between Sequential and Parallel for Multithreading with Queueing Network

This work deals with minimizing the computing time for matrix inversions used in the queueing system models or otherwise. The time is reduced considerably and is proportional to the number of the used threads in parallel

The simulation of transport processes in cementitious materials with embedded healing systems

A new model for simulating the transport of healing agents in self-healing (SH) cementitious materials is presented. The model is applicable to autonomic SH material systems in which embedded channels, or vascular networks, are used to supply healing agents to damaged zones. The essential numerical components of the model are a crack flow model, based on the Navier-Stokes equations, which is coupled to the mass balance equation for simulating unsaturated matrix flow. The driving forces for the crack flow are the capillary meniscus force and the force derived from an external (or internal) pressure applied to the liquid healing agent. The crack flow model component applies to non-uniform cracks and allows for the dynamic variation of the meniscus contact angle, as well as accounting for inertial terms. Particular attention is paid to the effects of curing on the flow characteristics. In this regard, a kinetic reaction model is presented for simulating the curing of the healing agent and a set of relationships established for representing the variation of rheological properties with the degree of cure. Data obtained in a linked experimental programme of work is employed to justify the choice and form of the constitutive relationships, as well as to calibrate the model’s evolution functions. Finally, a series of validation examples are presented that include the analysis of a series of concrete beam specimens with an embedded vascular network. These examples demonstrate the ability of the model to capture the transport behaviour of this type of SH cementitious material system

Ocular medicines in children: the regulatory situation related to clinical research

<p>Abstract</p> <p>Background</p> <p>Many ocular medications are prescribed for paediatric patients, but the evidence for their rational use is very scant. This study was planned to compare the availability and the licensing status of ocular medications marketed in Italy, the United Kingdom (UK), and the United States of America (USA) related to the amount of published and un-published RCTs testing these drugs in the paediatric population.</p> <p>Methods</p> <p>A quantitative analysis was performed to evaluate the number of ocular medications with a paediatric license in Italy, the UK, and the USA. A literature search was also performed in MEDLINE, EMBASE, and The Cochrane Central Register of Controlled Trials for randomized controlled trials (RCTs) on ophthalmic pharmacological therapy in children aged < 18 years, published up to December 2010. A search in the international clinical trial registries, the list of paediatric investigation plans (PIPs) approved by European Medicines Agency (EMA), and the table of medicines with new paediatric information approved by Food and Drug Administration (FDA) was also performed.</p> <p>Results</p> <p>In all, of 197 drugs identified, 68 (35%) single drugs are licensed for paediatric use at least in one considered country, while 23 (12%) were marketed in all three countries. More specifically, in Italy 43 single drugs (48% of those marketed) had a paediatric license, while 39 (64%) did in the UK and 22 (54%) did in the USA. Only 13 drugs were marketed with a paediatric license in all countries.</p> <p>The percentage of drugs licensed for paediatric use and for which at least one RCT had been performed ranged between 51% in Italy and 55% in the USA. No published RCTs were found for 11 (48%) drugs licensed for paediatric use in all three countries. In all, 74 (35%) of the retrieved RCTs involved mydriatic/cycloplegic medications.</p> <p>A total of 62 RCTs (56% completed) on 46 drugs were found in the international clinical trial registries. Cyclosporin and bevacizumab were being studied in many ongoing trials. Twenty-six drugs had new paediatric information approved by FDA based on new paediatric clinical trials, while only 4 PIPs were approved by EMA.</p> <p>Conclusions</p> <p>There is a pressing need for further research and clinical development in the pediatric ophthalmic area, where effective up-to-date treatments, and additional research and education on use in children, remain priorities.</p

Brazilian Consensus on Photoprotection

Brazil is a country of continental dimensions with a large heterogeneity of climates and massive mixing of the population. Almost the entire national territory is located between the Equator and the Tropic of Capricorn, and the Earth axial tilt to the south certainly makes Brazil one of the countries of the world with greater extent of land in proximity to the sun. The Brazilian coastline, where most of its population lives, is more than 8,500 km long. Due to geographic characteristics and cultural trends, Brazilians are among the peoples with the highest annual exposure to the sun. Epidemiological data show a continuing increase in the incidence of nonmelanoma and melanoma skin cancers. Photoprotection can be understood as a set of measures aimed at reducing sun exposure and at preventing the development of acute and chronic actinic damage. Due to the peculiarities of Brazilian territory and culture, it would not be advisable to replicate the concepts of photoprotection from other developed countries, places with completely different climates and populations. Thus the Brazilian Society of Dermatology has developed the Brazilian Consensus on Photoprotection, the first official document on photoprotection developed in Brazil for Brazilians, with recommendations on matters involving photoprotection

Padatan Tersuspensi di Muara Sungai Rokan Kabupaten Rokan Hilir Provinsi Riau

This research was conducted on October 2016 at Estuary of Rokan River Rokan Hilir Regency Riau Province. This study aimed to find out how big suspended solid in Estuary of Rokan River. The method used survey and purposive sampling. Results showed the suspended solid on base from 60 mg/l for station 5,6,11 and 520 mg/l for station 4. Showed the suspended solid on surface from 50 mg/l for station 3,6,11 and110 mg/l for station 10. Based on data obtained, it can be concluded that total suspended solid present in the Estuary of Rokan River is high

Effects of a reduced inner diameter of hollow fibers in hemodialyzers

Background. The clearance of middle molecules in high-flux hemodialyzers is due to the higher contribution of convection in the overall solute transport. Although net filtration can be maintained low by the machine control, internal filtration in the proximal parr of the dialyzer remains high. The final fluid balance is achieved by significant amounts of backfiltration in the distal part of the dialyzer. To increase further middle molecule clearance (MMK), hemodiafiltration has been used. This technique, however, requires complex machines and large amounts of substitution fluid. We present a novel solution to increase the convective transport of middle molecules in high Aux dialyzers without the need for substitution fluids. In particular, high-flux dialyzers with a reduced hollow fiber diameter are compared with standard dialyzers in terms of internal filtration and solute clearances. Methods. Hemodialyzers with 175 mu inner diameter polysulfone fibers were compared with standard 200 mu polysulfone hollow fiber dialyzers. The study was carried out in vitro using a previously published method to measure internal filtration and backfiltration rates. The method is based on the detection by a gamma camera of segmental variations in concentration along the length of the dialyzer of a nondiffusable Tc99-labeled marker molecule injected in the blood in vitro circuit. At the same time, pressures were detected in the blood and dialysate compartment. The system was operated at zero net filtration maintaining volumetrically constant both dialysate and blood circuits. In vivo clearances were also measured for solutes with different molecular weight. Results. The pressure drop in the blood compartment at 300 mL/min of blood flow passed from 112 to 159 mm Hg. At the same blood flow, the internal filtration-backfiltration rates increased from 23.1 to 48.2 mL/min. This resulted in a significant increase of in vivo in clearances of vitamin Bi, and inulin of more than 30%. Urea, creatinine, and phosphate clearance did not display any change. Conclusions. A reduction of the inner diameter of the hollow fibers in high-flux dialyzers may result in a significant increase of the blood compartment resistance. In turn, this results in increased rates of internal filtration and backfiltration. The practical effect in clinical dialysis is demonstrated on middle molecules. While, in fact, the clearances for small solutes such as urea and creatinine are not affected, the clearances of larger solutes such as vitamin B-12 Or inulin increase significantly (P < 0.01)