44 research outputs found
Window Query Processing with Proxy Cache
A location dependent query (LDQ) result set is valid only in a specific region called the validity region (VR). While limiting the validity of a particular result set to a given area, the VR may also be used in caching implementations to determine if cached results satisfy semantically equivalent queries. Existing LDQ caching schemes rely on the database servers to provide the VR at a cost of high computational overhead. Alternatively, a LDQ proxy cache, which approximates the VR can be employed, freeing the database servers from the high cost of calculating the VR. A LDQ proxy cache architecture is proposed to compute an estimated validity region (EVR) based on the observed querying history at the proxy server. We present an algorithm - Window_EVR - for the LDQ proxy to compute the EVR for a window query result set. The simulation results show that LDQ proxy caching using the Window_EVR algorithm significantly reduces both the window query response time and the workload at the database servers while maintaining query result set accuracy
Comparative assessment of in vitro and in silico methods for aerodynamic characterization of powders for inhalation
In vitro assessment of dry powders for inhalation (DPIs) aerodynamic performance is an inevitable test in DPI development. However, contemporary trends in drug development also implicate the use of in silico methods, e.g., computational fluid dynamics (CFD) coupled with discrete phase modeling (DPM). The aim of this study was to compare the designed CFD-DPM outcomes with the results of three in vitro methods for aerodynamic assessment of solid lipid microparticle DPIs. The model was able to simulate particle-to-wall sticking and estimate fractions of particles that stick or bounce off the inhaler’s wall; however, we observed notable differences between the in silico and in vitro results. The predicted emitted fractions (EFs) were comparable to the in vitro determined EFs, whereas the predicted fine particle fractions (FPFs) were generally lower than the corresponding in vitro values. In addition, CFD-DPM predicted higher mass median aerodynamic diameter (MMAD) in comparison to the in vitro values. The outcomes of different in vitro methods also diverged, implying that these methods are not interchangeable. Overall, our results support the utility of CFD-DPM in the DPI development, but highlight the need for additional improvements in these models to capture all the key processes influencing aerodynamic performance of specific DPIs
Assessment of information resources for people with hypodontia
Aim: To assess the adequacy of patient information to support understanding and decision-making for people affected by hypodontia.
Methods: 1) Questionnaire to understand the provision of patient information by dentists; 2) Systematic search to identify online open-access patient information; 3) Quality assessment of written patient information.
Results: Questionnaire response rate was 49% (319/649); 91% examined and/or treated people with hypodontia. Most general dentists referred patients to specialist services without providing written hypodontia information. The majority of dental specialists provide patient leaflets but less than a third used web-resources. Only 19% of respondents felt current resources were fit-for-purpose. Thirty-one patient resources (18 leaflets and 13 online) were assessed against quality criteria. The aim of the resource was seldom explicit, the content was often incomplete and variation in readability scores indicated high levels of literacy were required.
Discussion: Access to, and quality of, patient information for hypodontia is inadequate. Current resources are not sufficiently comprehensive to prepare young patients to engage in shared dental care decisions with their parents and/or dental professionals.
Conclusion: There is a need for improved access to, and provision of, information about hypodontia if dental professionals want to meet best practice guidance and involve patients in shared decision-making
Evaluating susceptibility of karst dolines (sinkholes) for collapse in Sango, Tennessee, USA
Dolines or sinkholes are earth depressions that develop in soluble rocks complexes such as limestone, dolomite, gypsum, anhydrite, and halite; dolines appear in a variety of shapes from nearly circular to complex structures with highly curved perimeters. The occurrence of dolines in the studied karst area is not random; they are the results of geomorphic, hydrologic and chemical processes that have caused partial subsidence, even total collapse of the land surface, when voids and caves are present in the bedrock and the regolith arch overbridging these voids is unstable. In the study area, the majority of collapses occur in the regolith (bedrock cover) that bridges voids in the bedrock. Because these collapsing dolines can damage property and cause even the loss of lives, there is a need to develop methods for evaluating karst hazards; such methods can be used by planners and practitioners for urban and economic development, especially in regions with a growing population. The purpose of this project is threefold: 1) to develop a karst feature database, 2) to investigate critical indicators associated with doline collapse, and 3) to design a doline susceptibility model for potential doline collapse based on external morphometric data. The study revealed the presence of short range spatial dependence in the distribution of the dolines’ morphometric parameters such as circularity, geographic orientation of the main doline axes and the length-to-width doline ratios; therefore, geostatistics can be used to spatially evaluate the susceptibility of the karst area for doline collapse using the probability of occurrence of these critical parameters. The partial susceptibility estimates were combined into final spatial probabilities enabling the identification of areas where undetected dolines may cause significant hazards
FPGA implementation of fuzzy medical decision support system for disc hernia diagnosis
The aim of this study was to create a decision support system for disc hernia diagnostics based on real measurements of foot force values from sensors and fuzzy logic, as well as to implement the system on Field Programmable Gate Array (FPGA). The results show that the created fuzzy logic system had the 92.8% accuracy for pre-operational diagnosis and very high match between the Matlab and FPGA output (94.2% match for pre-operational condition, and 100% match for the post-operational and after physical therapy conditions). Interestingly enough, our system is also able to detect improvements in patient condition after the surgery and physical therapy. The main benefit of using FPGAs in this study is to create an inexpensive, portable expert system for real time acquisition, processing and providing the objective recommendation for disc hernia diagnosis and tracking the condition improvement
Alternatywne PMB produkowane z odpadów recyklingowych PMMA/ATH
With development of production processes in refineries production of bitumen is decreasing, as well as the quality of produced bitumen. On the market this brings increased demand for bitumen accompanied by the demand for additives to improve such low quality bitumen. Many different types of additives are used, but most commonly SBS is added. Usage of additives bring additional direct costs, due to market price of additives and indirect cost due to adjustments in the technological process as such as additional mixing device in bitumen tanks, elevated temperature of asphalt or prolongation in mixing time. A topic of our research was development low price asphalt additive from waste poly-methyl methacrylate filled with a fine dispersion aluminium trihydrate (PMMA/ATH). Additionally with paraffin wax it was used as modifying agents for 70/100 paving grade bitumen. With regard to performance of modified asphalt mixtures, it was found that both additives considerably reduce moisture susceptibility and formation of ruts. With laboratory tests and field trial we found that combined technology PMA (polymer modified asphalt) and WMA (warm mix asphalt) technologies resulted in optimized production and excellent performance of pavement material.Wraz z rozwojem procesu produkcyjnego w rafineriach zmniejszyła się produkcja bituminu, jak również jakość produkowanego bituminu. Niesie to ze sobą zwiększenie zapotrzebowania na bitumin, towarzyszy; temu popyt na dodatki uszlachetniające. Używanych jest wiele rodzajów dodatków, lecz najczęściej dodawanym jest SBS. Użycie dodatków powoduje dodatkowe koszty bezpośrednie - jest to spowodowane ceną rynkową dodatków - jak również koszty pośrednie, co jest spowodowane zmianami w procesie technologicznym, takimi jak dodatkowe urządzenia mieszające w kadziach bituminowych, wzrost temperatury asfaltu lub wydłużenie czasu mieszania. Tematem badań było osiągnięcie niskiej ceny dodatku asfaltu z odpadów polimetylowego metakrylanu wypełnionego dobrze zdyspersowanym trihydratem aluminium (PMMA/ATH). Dodatkowo użyto wosku parafinowego jako środka modyfikującego dla bituminowych płyt chodnikowych 70/100. W odniesieniu do wydajności zmodyfikowanych mieszanin asfaltowych stwierdzono, że oba dodatki znacznie zmniejszyły podatność na wilgoć i powstawanie kolein. Z badań laboratoryjnych i prób w terenie wynika, że połączenie technologii PMA (asfalt modyfikowany polimerowo) oraz WMA (ciepła mieszanka asfaltowa) zaowocowało technologiami zoptymalizowanymi w produkcji i doskonałą wydajnością materiału nawierzchni
Electrochromism and Swelling of Polypyrrole Membranes: An Electrochemical and Ellipsometric Study
The growth of polypyrrole (Ppy) layers on gold electrodes in nearly neutral pH solutions is analysed using “in situ” voltametric and ellipsometric techniques. Different film structures are obtained depending on the potentiodynamic programme and the composition of the electrolyte. More compact dodecylsulphate-(DS) doped Ppy layers were grown at 1.2 V versus RHE than those obtained by applying a higher potential. The more compact layers correspond to the growth of an oxidised Ppy/DS layer that shows low pseudo capacity behaviour. After dipping, the doped Ppy/DS film in KCl solution-significant variations in optical indices and thickness are detected as a function of the applied potential. Higher electrochromism as well as decrease in film thickness after cathodisation is achieved. The optical indices and the thickness of the Ppy layer formed under different applied potential/time programmes are estimated
The Electrosorption of Methane and Its Potentiodynamic Electrooxidation on Platinized Platinum
Optimization and prediction of ibuprofen release from 3D DLP printlets using artificial neural networks
© 2019 by the authors. Licensee MDPI, Basel, Switzerland. The aim of this work was to investigate effects of the formulation factors on tablet printability as well as to optimize and predict extended drug release from cross-linked polymeric ibuprofen printlets using an artificial neural network (ANN). Printlets were printed using digital light processing (DLP) technology from formulations containing polyethylene glycol diacrylate, polyethylene glycol, and water in concentrations according to D-optimal mixture design and 0.1% w/w riboflavin and 5% w/w ibuprofen. It was observed that with higher water content longer exposure time was required for successful printing. For understanding the effects of excipients and printing parameters on drug dissolution rate in DLP printlets two different neural networks were developed with using two commercially available softwares. After comparison of experimental and predicted values of in vitro dissolution at the corresponding time points for optimized formulation, the R2 experimental vs. predicted value was 0.9811 (neural network 1) and 0.9960 (neural network 2). According to difference f1 and similarity factor f2 (f1 = 14.30 and f2 = 52.15) neural network 1 with supervised multilayer perceptron, backpropagation algorithm, and linear activation function gave a similar dissolution profile to obtained experimental results, indicating that adequate ANN is able to set out an input–output relationship in DLP printing of pharmaceutics