Raman scattering studies of temperature- and field-induced melting of charge order in (La,Pr,Ca)MnO3_{3}

We present Raman scattering studies of the structural and magnetic phases that accompany temperature- and field-dependent melting of charge- and orbital-order (COO) in La0.5Ca0.5MnO3 and La0.25Pr0.375Ca0.375MnO3. Our results show that thermal and field-induced COO melting in La0.5Ca0.5MnO3 exhibits three stages in a heterogeneous melting process associated with a structural change: a long-range, strongly JT distorted/COO regime; a coexistence regime; and weakly JT distorted/PM or FM phase. We provide a complete structural phase diagram of La0.5Ca0.5MnO3 for the temperature and field ranges 6<=T<=170 K and 0<=H<=9 T. We also investigate thermal and field-induced melting in La0.25Pr0.375Ca0.375MnO3 to elucidate the role of disorder in melting of COO. We find that while thermal melting of COO in La0.25Pr0.375Ca0.375MnO3 is quite similar to that in La0.5Ca0.5MnO3, the field-induced transition from the COO phase to the weakly JT-distorted/FM phase in La0.25Pr0.375Ca0.375MnO3 is very abrupt, and occurs at significantly lower fields (H~2 T at T~0 K) than in La0.5Ca0.5MnO3 (H~30 T at T=0 K). Moreover, the critical field H_c increases with increasing temperature in La0.25Pr0.375Ca0.375MnO3 in contrast to La0.5Ca0.5MnO3. To explain these differences, we propose that field-induced melting of COO in La0.25Pr0.375Ca0.375MnO3 is best described as the field-induced percolation of FM domains, and we suggest that Griffiths phase physics may be an appropriate theoretical model for describing the unusual temperature- and field- dependent transitions observed in La0.25Pr0.375Ca0.375MnO3.Comment: 14 pages, 8 figures, to be published in PR

Stability indicating RP-HPLC method for the estimation of flucloxacillin sodium in a tablet dosage form

A Simple, accurate and precise method was developed and validated for the determination of flucloxacillin sodium in its tablet dosage form. The separation was eluted on xterra c18 column (4.6x150mm, 5micron) using a mixture of octane buffer and methanol as mobile phase in a ratio of (30:70) which was pumped through column at a flow rate of&nbsp; 1ml/min. Optimised wavelength for flucloxacillin was 237nm, the retention time was 2.305minutes and the percentage purity was found to be 98.14%. System suitability parameters such as theoretical plate and tailing factor for flucloxacillin sodium was found to be 2991.64 and 1.90 respectively, the proposed method was validated as per ICH guidelines (ICH, Q2 AND (R1)) the method was found to be linear at the concentration range of 20-100µg/ml and the correlation coefficient (r2) value was found to be 0.9994 percentage RSD for precision was 0.9% and percentage RSD for ruggedness was 0.5%. The precision study was precise, robust and repeatable. The LOD and LOQ values are 2.98 and 9.98 respectively. Hence the suggested RP-HPLC method can be used for routine analysis for flucloxacillin sodium in tablet dosage form

Venus - Preliminary science objectives and experiments for use in advanced mission studies

Mission planning and experiment design for future Mariner-type Venus space probe

Dizajniranje i vrednovanje okularnih umetaka moksifloksacin hidroklorida

The objective of the present investigation was to prepare and evaluate ocular inserts of moxifloxacin. An ocular insert was made from an aqueous dispersion of moxifloxacin, sodium alginate, polyvinyl alcohol, and dibutyl phthalate by the film casting method. The ocular insert (5.5 mm diameter) was cross-linked by CaCl2 and was coated with Eudragit S-100, RL-100, RS-100, E-100 or Eudragit L-100. The in vitro drug drainage/permeation studies were carried out using an all-glass modified Franz diffusion cell. The drug concentration and mucoadhesion time of the ocular insert were found satisfactory. Cross-linking and coating with polymers extended the drainage from inserts. The cross-linked ocular insert coated with Eudragit RL-100 showed maximum drug permeation compared to other formulations.Cilj rada bio je priprava i evaluacija okularnih umetaka moksifloksacina. Okularni umetak izrađen je od vodene suspenzije moksifloksacina, natrijevog alginata, polivinilnog alkohola i dibutil-ftalata metodom odlijevanja filma. Okularni umetak (promjera 5,5 mm) umrežen je pomoću CaCl2 i obložen Eudragitom S-100, RL-100, RS-100, E-100 ili Eudragit L-100. In vitro drenaža/permeacija lijeka proučavana je koristeći staklenu modificiranu Franzovu difuzijsku ćeliju. Koncentracija lijeka i vrijeme mukoadhezije okularnih umetaka bili su zadovoljavajući. Umrežavanje i oblaganje polimerima produljilo je drenažu iz umetaka. Umreženi okularni umetci obloženi s Eudragit RL-100 pokazali su veću permeaciju lijeka u odnosu na ostale pripravke

Creating ecologically sound buildings by integrating ecology, architecture and computational design

1. Research is revealing an increasing number of positive effects of nature for humans. At the same time, biodiversity in cities, where most humans live, is often low or in decline. Tangible solutions are needed to increase urban biodiversity. 2. Architecture is a key discipline that has considerable influence on the built-up area of cities, thereby influencing urban biodiversity. In general, architects do not design for biodiversity. Conversely, urban conservation planning generally focuses on the limited space free of buildings and does not embrace architecture as an important discipline for the creation of urban green infrastructure. 3. In this paper, we argue that the promotion of biodiversity needs to become a key driving force of architectural design. This requires a new multi-species design paradigm that considers both human and non-human needs. Such a design approach needs to maintain the standards of the architectural profession, including the aim to increase the well-being of humans in buildings. Yet, it also needs to add other stakeholders, organisms such as animals, plants and even microbiota. New buildings designed for humans and other inhabitants can then increase biodiversity in cities and also increase the benefits that humans can derive from close proximity to nature. 4. We review the challenges that this new design approach poses for both architecture and ecology and show that multi-species-design goes beyond existing approaches in architecture and ecology. The new design approach needs to make ecological knowledge available to the architectural design process, enabling practitioners to find architectural solutions that can facilitate synergies from a multi-species perspective. 5. We propose that a first step in creating such a multi-species habitat is the design of buildings with an ecolope, a multi criteria-designed building envelope that takes into account the needs of diverse organisms. Because there is no framework to design such an ecolope, we illustrate how multi-species design needs to draw on knowledge from ecology, as well as architecture, and design computation. 6. We discuss how architectures designed via a multi-species approach can be an important step in establishing beneficial human-nature relationships in cities, and contribute to human well-being and biodiversity conservation.Read the free Plain Language Summary for this article on the Journal blog

Radio Astronomy

Contains reports on five research projects.National Aeronautics and Space Administration (Grant NGL 22-009-016)National Aeronautics and Space Administration (Grant NGL 22-009-421)National Science Foundation (Grant GP-13056)California Institute of Technology Contract 95256

Radio Astronomy

Contains reports on four research projects.Joint Services Electronics Program (Contract DAAB07-71-C-0300)California Institute of Technology (Contract 952568)National Aeronautics and Space Administration (Contract NAS1-10693)National Science Foundation (Grant GP-21348A#2

Controlled Exposures to Air Pollutants and Risk of Cardiac Arrhythmia

BACKGROUND: Epidemiological studies have reported associations between air pollution exposure and increases in cardiovascular morbidity and mortality. Exposure to air pollutants can influence cardiac autonomic tone and reduce heart rate variability, and may increase the risk of cardiac arrhythmias, particularly in susceptible patient groups. OBJECTIVES: We investigated the incidence of cardiac arrhythmias during and after controlled exposure to air pollutants in healthy volunteers and patients with coronary heart disease. METHODS: We analyzed data from 13 double-blind randomized crossover studies including 282 participants (140 healthy volunteers and 142 patients with stable coronary heart disease) from whom continuous electrocardiograms were available. The incidence of cardiac arrhythmias was recorded for each exposure and study population. RESULTS: There were no increases in any cardiac arrhythmia during or after exposure to dilute diesel exhaust, wood smoke, ozone, concentrated ambient particles, engineered carbon nanoparticles, or high ambient levels of air pollution in either healthy volunteers or patients with coronary heart disease. CONCLUSIONS: Acute controlled exposure to air pollutants did not increase the short-term risk of arrhythmia in participants. Research employing these techniques remains crucial in identifying the important pathophysiological pathways involved in the adverse effects of air pollution, and is vital to inform environmental and public health policy decisions

The relationship of air pollution and surrogate markers of endothelial dysfunction in a population-based sample of children

<p>Abstract</p> <p>Background</p> <p>This study aimed to assess the relationship of air pollution and plasma surrogate markers of endothelial dysfunction in the pediatric age group.</p> <p>Methods</p> <p>This cross-sectional study was conducted in 2009-2010 among 125 participants aged 10-18 years. They were randomly selected from different areas of Isfahan city, the second large and air-polluted city in Iran. The association of air pollutants' levels with serum thrombomodulin (TM) and tissue factor (TF) was determined after adjustment for age, gender, anthropometric measures, dietary and physical activity habits.</p> <p>Results</p> <p>Data of 118 participants was complete and was analyzed. The mean age was 12.79 (2.35) years. The mean pollution standards index (PSI) value was at moderate level, the mean particular matter measuring up to 10 μm (PM₁₀) was more than twice the normal level. Multiple linear regression analysis showed that TF had significant relationship with all air pollutants except than carbon monoxide, and TM had significant inverse relationship with ozone. The odds ratio of elevated TF was significantly higher in the upper vs. the lowest quartiles of PM₁₀, ozone and PSI. The corresponding figures were in opposite direction for TM.</p> <p>Conclusions</p> <p>The relationship of air pollutants with endothelial dysfunction and pro-coagulant state can be an important factor in the development of atherosclerosis from early life. This finding should be confirmed in future longitudinal studies. Concerns about the harmful effects of air pollution on children's health should be considered a top priority for public health policy; it should be underscored in primordial and primary prevention of chronic diseases.</p

Regulatory T cells and their role in rheumatic diseases: a potential target for novel therapeutic development

Regulatory T cells have an important role in limiting immune reactions and are essential regulators of self-tolerance. Among them, CD4+CD25high regulatory T cells are the best-described subset. In this article, we summarize current knowledge on the phenotype, function, and development of CD4+CD25high regulatory T cells. We also review the literature on the role of these T cells in rheumatic diseases and discuss the potential for their use in immunotherapy