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Dash S.,Science 37 | Nath L.,Dibrugarh University
Acta Poloniae Pharmaceutica - Drug Research | Year: 2010

In this paper we review the mathematical models used to determine the kinetics of drug release from drug delivery systems. The quantitative analysis of the values obtained in dissolution/release rates is easier when mathematical formulae are used to describe the process. The mathematical modeling can ultimately help to optimize the design of a therapeutic device to yield information on the efficacy of various release models.

Naldoni A.,CNR Institute of Molecular Science and Technologies | Allieta M.,University of Milan | Santangelo S.,University of Reggio Calabria | Marelli M.,CNR Institute of Molecular Science and Technologies | And 5 more authors.
Journal of the American Chemical Society | Year: 2012

The increasing need for new materials capable of solar fuel generation is central in the development of a green energy economy. In this contribution, we demonstrate that black TiO 2 nanoparticles obtained through a one-step reduction/crystallization process exhibit a bandgap of only 1.85 eV, which matches well with visible light absorption. The electronic structure of black TiO 2 nanoparticles is determined by the unique crystalline and defective core/disordered shell morphology. We introduce new insights that will be useful for the design of nanostructured photocatalysts for energy applications. © 2012 American Chemical Society.

Mehrad B.,University of Virginia | Clark N.M.,Loyola University | Zhanel G.G.,University of Manitoba | Lynch J.P.,Science 37
Chest | Year: 2015

Aerobic gram-negative bacilli, including the family of Enterobacteriaceae and non-lactose fermenting bacteria such as Pseudomonas and Acinetobacter species, are major causes of hospital-acquired infections. The rate of antibiotic resistance among these pathogens has accelerated dramatically in recent years and has reached pandemic scale. It is no longer uncommon to encounter gram-negative infections that are untreatable using conventional antibiotics in hospitalized patients. In this review, we provide a summary of the major classes of gram-negative bacilli and their key mechanisms of antimicrobial resistance, discuss approaches to the treatment of these diffi cult infections, and outline methods to slow the further spread of resistance mechanisms. © 2015 American College Of Chest Physicians.

According to an understanding of casual conversation articulated by various theories of discourse analysis including Conversation Analysis (Sacks et al., 1974), pragmatics (Levinson, 1983) and politeness theory (Brown and Levinson, 1987), it is extremely unlikely that silence would ever be regarded as an appropriate response to a question or accusation. Yet, in the specialised institutional setting of a police interview, it is expected by the legislators in many jurisdictions that ordinary people will be able to access this interactional resource unproblematically, and presumably without any assumption of listener prejudice.An analysis of the interactional strategies of police interview participants in 13 police interviews recorded in Victoria, Australia demonstrates that the contributions of the suspect are highly constrained in a number of ways, including allowable turn types and the management of topic initiations. If assumptions about 'preferred responses' based on ordinary conversation are used to interpret non-response in this particular institutional setting, then these interactionally restricted contributions, which will be presented as evidence, may be susceptible to adverse inference in a way that is unlikely to be addressed by the judicial system. This paper concludes that by applying principles of pragmatics, and in particular the use of preference, it is possible to present a case against the erosion of the defendant's right to silence. © 2011 Elsevier B.V.

A recent randomized, double-blind, parallel-group, active-controlled, multicenter study of 255 patients ≥40 years of age with chronic obstructive pulmonary disease (COPD) showed that combined formoterol (FOR) and tiotropium (TIO) treatment in patients with COPD significantly improved lung function as well as symptoms and other patient-reported outcomes compared with TIO alone. FOR and TIO are long-acting bronchodilators that represent the β 2-adrenergic agonist and anticholinergic classes, respectively. However, the possible influence of smoking status, inhaled corticosteroid (ICS) use, baseline disease severity, and gender differences on bronchodilator efficacy requires further investigation. Using data from the previously published study mentioned above, a post hoc analysis was performed to examine the efficacy of combined FOR + TIO treatment compared with TIO monotherapy in subgroup analyses of men and women, current and ex-smokers, ICS users and non-ICS users, and patients with moderate and severe/very severe COPD. Efficacy comparisons were based on the changes in forced expiratory volume in 1 s measured 0-4 h after the morning dose (FEV 1 AUC 0-4h). After a run-in period, patients were treated for 12 weeks with either FOR 12 μg twice daily (BID) plus TIO 18 μg once daily (QD) in the morning (AM, n = 124) or with FOR placebo BID plus TIO 18 μg QD AM (n = 131). The least squares mean change from baseline in the normalized FEV 1 AUC 0-4h was assessed using analysis of covariance. With the exception of treatment differences at week 4 in smokers and subjects with "very severe" COPD, and at weeks 4, 8, and 12 for ICS users and non-ICS users (p values not determined), FOR + TIO was significantly superior (P < 0.05) to TIO alone at all time points (weeks 4, 8, 12, and endpoint), regardless of gender, smoking status, ICS use, or COPD severity. We conclude that coadministered FOR + TIO significantly improves lung function compared with TIO treatment alone in COPD patients regardless of differences in patient subgroups. © 2010 Elsevier Ltd.

Attolini G.,Science 37 | Bosi M.,Science 37 | Ferrari C.,Science 37 | Melino F.,Science 37
Applied Energy | Year: 2013

In the last decade, the thermo-photo-voltaic (TPV) generator has gained an increasing attention as cogeneration system for the distributed generation sector. Nevertheless, these systems are not fully developed and studied: several aspects need to be further investigated and completely understood. The aim of this study is to highlight and outline the main design guidelines for a thermo-photo-voltaic (TPV) generator with a specific attention to the emitter section. More in details, an investigation of the role of the emitter size will be developed by considering its influence on spectral efficiency (defined as the ratio between the emitted radiation in the useful range for photovoltaic conversion and the introduced power with fuel); by using simplified assumptions, the spectral efficiency as a function of the emitter area in four different TPV configurations will be estimated. The achieved results show specific power values per unit emitter area significantly larger than in prototypes realized up to date. Further, the developed analysis allows to show the role of the optical filter and of the air pre-heating exchanger in order to increases the spectral efficiency of the system, being equal the considered power density. © 2012 Elsevier Ltd.

Li H.,Italian Institute of Technology | Brescia R.,Italian Institute of Technology | Povia M.,Italian Institute of Technology | Prato M.,Italian Institute of Technology | And 4 more authors.
Journal of the American Chemical Society | Year: 2013

We present the synthesis of novel disk-shaped hexagonal Cu2Te nanocrystals with a well-defined stoichiometric composition and tunable diameter and thickness. Subsequent cation exchange of Cu to Cd at high temperature (180 C) results in highly fluorescent CdTe nanocrystals, with less than 1 mol % of residual Cu remaining in the lattice. The procedure preserves the overall disk shape, but is accompanied by a substantial reconstruction of the anion sublattice, resulting in a reorientation of the c-axis from the surface normal in Cu2Te into the disk plane in CdTe nanodisks. The synthesized CdTe nanodisks show a continuously tunable photoluminescence (PL) peak position, scaling with the thickness of the disks. The PL lifetime further confirms that the CdTe PL arises from band-edge exciton recombination; that is, no Cu-related emission is observed. On average, the recombination rate is about 25-45% faster with respect to their spherical quantum dots counterparts, opening up the possibility to enhance the emission rate at a given wavelength by controlling the nanocrystal shape. Finally, with a PL quantum efficiency of up to 36% and an enhanced PL stability under ambient conditions due to a monolayer of CdS formed on the nanocrystal surface during cation exchange, these flat quantum disks form an interesting enrichment to the current family of highly fluorescent, shape-controlled nanocrystals. © 2013 American Chemical Society.

Yvon-Durocher G.,Queen Mary, University of London | Montoya J.M.,Queen Mary, University of London | Montoya J.M.,Science 37 | Trimmer M.,Queen Mary, University of London | Woodward G.,Queen Mary, University of London
Global Change Biology | Year: 2011

Organism size is one of the key determinants of community structure, and its relationship with abundance can describe how biomass is partitioned among the biota within an ecosystem. An outdoor freshwater mesocosm experiment was used to determine how warming of~4°C would affect the size, biomass and taxonomic structure of planktonic communities. Warming increased the steepness of the community size spectrum by increasing the prevalence of small organisms, primarily within the phytoplankton assemblage and it also reduced the mean and maximum size of phytoplankton by approximately one order of magnitude. The observed shifts in phytoplankton size structure were reflected in changes in phytoplankton community composition, though zooplankton taxonomic composition was unaffected by warming. Furthermore, warming reduced community biomass and total phytoplankton biomass, although zooplankton biomass was unaffected. This resulted in an increase in the zooplankton to phytoplankton biomass ratio in the warmed mesocosms, which could be explained by faster turnover within the phytoplankton assemblages. Overall, warming shifted the distribution of phytoplankton size towards smaller individuals with rapid turnover and low standing biomass, resulting in a reorganization of the biomass structure of the food webs. These results indicate future environmental warming may have profound effects on the structure and functioning of aquatic communities and ecosystems. © 2010 Blackwell Publishing Ltd.

Tesic M.,Science 37 | Kiss F.,University of Novi Sad | Zavargo Z.,University of Novi Sad
Renewable and Sustainable Energy Reviews | Year: 2011

The aim of this paper is to give insight into the goals, instruments and planned measures of the Serbian Government in the field of renewable energy sources (RES). The method is based on an overview and analysis of adopted laws and regulations and other official documents. The results have revealed that progress has been made in this field in recent years. Midterm targets for the proportion of energy from RES in overall energy consumption have been defined; feed-in-tariffs have been adopted; legislative and socio-economic barriers of increased exploitation of RES have been analyzed and measures and activities were suggested for their resolution. The existing RES-related legislation, however, is imprecise and incomplete. Numerous bylaws, technical standards and guidelines are still outstanding. The key RES-related documents are inconsistent, lack clarity and are insufficiently decisive when implementing specific measures of incentives for production of RES-based energy. © 2010 Elsevier Ltd.

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