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Abstract Nanostructuring has rejuvenated great interest in thermoelectric (TE) based power generation by enabling enhanced performance in nano-grained TE materials over their bulk counterparts. In ZrNiSn based half-Heusler (HH), a promising n-type TE materials, we examine the prospects of nanostructuring by synthesizing nano-crystalline iso-electronically substituted n-type Zr 1-x Hf x NiSn HH alloys to achieve a state-of-the-art TE figure-of-merit ZT ∼ 1.2 at 873 K, which is ∼20% higher than its bulk counterparts and corresponds to high conversion efficiency of ∼9% with output power density ∼7 Wcm−2, estimated using cumulative temperature dependence model. Enhanced phonon scattering at nano-scale grain boundaries and crystal defects, arising from nanostructuring and mass defect fluctuation in Hf substituted ZrNiSn alloys resulted in significantly reduced thermal conductivity. It was found that the partial substitution at Zr site with its heavier homologue Hf causes variation in the carrier effective mass and carrier concentration, which at lower Hf concentration results in an enhancement in the power factor. Graphical abstract Image 1 Highlights • Realization of optimal Hf-content for maximum quality factor in ZrNiSn based half-heusler alloys. • A state-of-the-art ZT ~1.2 at 873 K was realised in n-type half-Heusler alloys at lower Hf-Content. • Theoretical estimation of thermoelectric performance by cumulative temperature dependence model. [ABSTRACT FROM AUTHOR]

This paper discusses the effect of meteorological parameters (temperature, relative humidity, solar radiation, pressure, wind speed, wind direction and precipitation) on indoor coarse (PM10) and fine (PM2.5 and PM1) particles in a naturally ventilated classroom. The indoor PM10, PM2.5 and PM1 mass concentrations and meteorological parameters were monitored for 222 days during winter, summer, monsoon and post monsoon seasons of 2011 and 2012. The occurrence of atmospheric stagnation, recirculation and ventilation events at the study site was also estimated. It was found that the occurrence of stagnation was comparatively more frequent in post monsoons (74–81%) and winters (53–76%), recirculation in monsoon season (46%) and ventilation in summer seasons (45–59%). Maximum PM concentrations were also observed under stagnant atmospheric conditions. The highest concentrations of coarse and fine particles in the classroom were associated with strong and low winds respectively. Among the other meteorological variables, temperature (R2 = 0.32–0.47), relative humidity (R2 = 0.34–0.36) and precipitation (R2 = 0.13–0.27) showed moderate dependence with indoor PM concentrations. However, solar radiation (R2 = 0.06–0.15) and atmospheric pressure (R2 = 0.16–0.21) showed poor correlation with indoor PM concentrations. [ABSTRACT FROM AUTHOR]

Abstract: Western blot analysis demonstrated that PC-12 cells express monomeric and dimeric forms of serine racemase (m-SR, d-SR) and that 1321N1 cells express m-SR. Quantitative RT-PCR and functional studies demonstrated that PC-12 cells express homomeric and heteromeric forms of nicotinic acetylcholine receptors (nAChR) while 1321N1 cells primarily express the α7-nAChR subtype. The effect of nAChR agonists and antagonists on SR activity and expression was examined by following concentration-dependent changes in intracellular d-Ser levels and SR protein expression. Incubation with (S)-nicotine increased d-Ser levels, which were attenuated by the α7-nAChR antagonist methyllycaconitine (MLA). Treatment of PC-12 cells with mecamylamine (MEC) produced a bimodal reduction of d-Ser reflecting MEC inhibition of homomeric and heteromeric nAChRs, while a unimodal curve was observed with 1321N1 cells, reflecting predominant expression of α7-nAChR. The nAChR subtype selectivity was probed using α7-nAChR selective inhibitors MLA and (R,S)-dehydronorketamine and α3β4-nAChR specific inhibitor AT-1001. The compounds reduced d-Ser in PC-12 cells, but only MLA and (R,S)-dehydronorketamine were effective in 1321N1 cells. Incubation of PC-12 and 1321N1 cells with (S)-nicotine, MEC and AT-1001 did not affect m-SR or d-SR expression, while MLA and (R,S)-dehydronorketamine increased m-SR expression but not SR mRNA levels. Treatment with cycloheximide indicated that increased m-SR was due to de novo protein synthesis associated with phospho-active forms of ERK1/2, MARCKS, Akt and rapamycin-sensitive mTOR. This effect was attenuated by treatment with the pharmacological inhibitors U0126, LY294002 and rapamycin, which selectively block the activation of ERK1/2, Akt and mTOR, respectively, and siRNAs directed against ERK1/2, Akt and mTOR. We propose that nAChR-associated changes in Ca2+ flux affect SR activity, but not expression, and that MLA and (R,S)-dehydronorketamine bind to allosteric sites on the α7-nAChR and promote multiple signaling cascades that converge at mTOR to increase m-SR levels. [Copyright &y& Elsevier]

Abstract: The effects of gabapentin (GBP) and (S)-pregabalin (PGB) on the intracellular concentrations of d-serine and the expression of serine racemase (SR) in PC-12 cells were determined. Intracellular d-serine concentrations were determined using an enantioselective capillary electrophoresis assay with laser-induced fluorescence detection. Increasing concentrations of GBP, 0.1–20μM, produced a significant decrease in d-serine concentration relative to control, 22.9±6.7% at 20μM (*p <0.05), with an IC50 value of 3.40±0.29μM. Increasing concentrations of PGB, 0.1–10μM, produced a significant decrease in d-serine concentration relative to control, 25.3±7.6% at 10μM (*p <0.05), with an IC50 value of 3.38±0.21μM. The compounds had no effect on the expression of monomeric-SR or dimeric-SR as determined by Western blotting. The results suggest that incubation of PC-12 cells with GBP and PGB reduced the basal activity of SR, which is most likely a result of the decreased Ca2+ flux produced via interaction of the drugs with the α2-δ subunit of voltage-gated calcium channels. d-Serine is a co-agonist of the N-methyl d-aspartate receptor (NMDAR) and reduced d-serine concentrations have been associated with reduced NMDAR activity. Thus, GBP and PGB may act as indirect antagonists of NMDAR, a mechanism that may contribute to the clinical effects of the drugs in neuropathic pain. [Copyright &y& Elsevier]

Abstract: According to Indian Systems of Medicine, Spilanthes acmella (L.) Murr. (Family – Asteraceae), is considered effective in the treatment of sexual deficiencies especially due to ageing. In the present study, characterization of ethanolic extracts of the Spilanthes acmella flower and its effect on general mating pattern, penile erection and serum hormone levels of normal male Wistar albino rats were investigated and compared with sildenafil citrate. In vitro nitric oxide release was also investigated in human corpus cavernosum cell line. As N-alkylamides are a promising group, their profiling was performed using a gradient reversed phase high performance liquid chromatography/electrospray ionization ion trap mass spectrometry (HPLC/ESI-MS) method on an embedded polar column. MS1 and MS2 fragmentation data were used for identification purposes. For assessment of sexual behavior, animals were divided into five groups of eight male rats. The extracts (50, 100 and 150mg/kgbodyweight/day) and sildenafil citrate (5mg/kgbodyweight/day) (positive control) were administered orally for 28 days. The behavioral and sexual parameters were observed at days 0, 15, 28 and after a lapse of 7 and 14 days of discontinuance of drug treatment. Five N-isobutylamides, one 2-methylbutylamide and one 2-phenylethylamide were identified. The orally administered extract had a dose dependent positive effect on mounting frequency, intromission frequency and ejaculation frequency and the most significant effects (p <0.05) were observed at 150mg/kg treatment, even after a lapse of 7 and 14 days of discontinuance of drug treatment. A dose dependent effect was also observed on the FSH, LH and testosterone serum levels. With 150mg/kg of ethanolic extract the values for FSH, LH and testosterone were 3.10±0.25mlU/ml, 6.87±0.18mlU/ml and 3.72±0.12ng/ml, respectively. In vitro nitric oxide release was 21.7±2.9μM, which was significantly higher compared to the control group (p <0.01). Sildenafil citrate exhibited also a significant effect on NO release, but no effect on hormone levels of rats was observed. The aphrodisiac potential of an ethanolic Spilanthes acmella extract was demonstrated in vitro and in vivo. N-Alkylamides might attribute to the improved sexual potential. Study lends support to the traditional utilization of S. acmella as a sexual stimulating agent. [Copyright &y& Elsevier]

Abstract: Three cardo bisphenols containing decahydronaphthalene group viz., 4,4′-(octahydro-2(1H)-naphthylidene)bisphenol, 4,4′-(octahydro-2(1H)-naphthylidene)bis-3-methylphenol and 4,4′-(octahydro-2(1H)-naphthylidene)bis-3,5-dimethylphenol were synthesized starting from commercially available 2-naphthol and were utilized for synthesis of new aromatic polyesters by phase transfer-catalyzed interfacial polycondensation with isophthaloyl chloride, terephthaloyl chloride and a mixture of isophthaloyl chloride and terephthaloyl chloride (50:50mol %). Inherent viscosities and number average molecular weights (M n) of polyesters were in the range 0.35–0.84 dL/g and 13,300–48,500 (Gel Permeation Chromatography, polystyrene standard), respectively. Polyesters were readily soluble in organic solvents such as dichloromethane, chloroform, tetrahydrofuran, meta-cresol, pyridine, N,N-dimethylformamide, N,N-dimethylacetamide, and 1-methyl-2-pyrrolidinone at room temperature and could be cast into tough, transparent and flexible films from their chloroform solutions. Wide-angle X-ray diffraction measurements revealed the amorphous nature of polyesters. The glass transition temperature of polyesters was in the range 207–287°C. The temperature at 10% weight loss (T 10), determined from thermogravimetric analysis of polyesters, was in the range 425–460°C indicating their good thermal stability. [Copyright &y& Elsevier]

The ternary intermetallic TiCoSb based half-Heusler (HH) alloys are prominent material exhibiting good p-type thermoelectric (TE) performance. In this work, we studied the implication of V and Nb as n-type aliovalent dopants on Ti crystallographic site of semiconducting TiCoSb based HH alloys for attaining higher TE performance in n-type counterparts. The carrier concentration optimization between semiconducting (Ti 1−x V x CoSb) and semi-metallic regime (Ti 1−x Nb x CoSb) had resulted in maximum TE figure-of-merit (ZT) of 0.22 and 0.52 at 873 K for optimized Ti 0.85 V 0.15 CoSb and Ti 0.85 Nb 0.15 CoSb HH compositions, respectively. These substitutional alloys were synthesized using arc-melting and consolidated using spark plasma sintering, which resulted in biphasic microstructure with in-situ phase segregation of heterogeneously distributed Ti-rich precipitates at all length scales within the HH matrix, are examined by microstructural analysis using X-ray diffraction and electron microscopy. Interestingly, higher power factor and simultaneous reduction of thermal conductivity is observed in both the doping as a result of optimal carrier concentration and enhanced phonon scattering. However, Nb-doped alloys exhibit higher carrier mobility and more significant lattice thermal conductivity reduction, thus establishing n-type Ti 1−x Nb x CoSb HH alloys as an equally promising counterpart of p-type TiCoSb for mid-temperature TE power generation. Image 1 • Compositional modulation by aliovalent doping in TiCoSb. • Nb-doping is better than V-doping at Ti-site in TiCoSb. • Half-Heusler alloys Ti 1−x Nb x CoSb with high ZT ~0.52 at 873 K. • All scale hierarchical architecture reduces lattice thermal conductivity. • Optimal concentration and higher carrier mobility results in high ZT. [ABSTRACT FROM AUTHOR]

Adverse impacts of volatile organic compounds (VOCs) released from the landfill sites into the atmosphere is a major concern in most urban areas. There exist a limited information on the effects of VOCs emitted from open dumpsite particularly for tropical climatic conditions. The present study reviews the source, concentrations and pathways of VOCs released from landfill sites into air and summarises their impacts on surrounding environment and nearby residents. Further, it provides insight on generation of secondary pollutants due to photochemical reactions between the VOCs released from landfill sites and compounds already existing in troposphere. VOCs released from landfill sites can undergo photochemical reactions with the hydroxyl radicals and NOx present in the troposphere to form O3, secondary organic aerosols (SOA) and intermediate products, which can deteriorate the air quality. Nevertheless, studies using mathematical simulation augmented by suitable laboratory experiments and continuous monitoring data can aid in detailed analysis on the mechanism of the secondary pollutant formation by VOCs emitted from the landfill sites. Findings of this study will open new avenue of research for further investigations on pathways of photochemical reactions of VOCs released from the landfill sites leading to secondary pollutant formation in proximate surface environment. [ABSTRACT FROM AUTHOR]

( R , R ′)-4′-methoxy-1-naphthylfenoterol [( R , R ′)-MNF] is a highly-selective β 2 adrenergic receptor (β 2 -AR) agonist. Incubation of a panel of human-derived melanoma cell lines with ( R , R ′)-MNF resulted in a dose- and time-dependent inhibition of motility as assessed by in vitro wound healing and xCELLigence migration and invasion assays. Activity of ( R , R ′)-MNF positively correlated with the β 2 -AR expression levels across tested cell lines. The anti-motility activity of ( R , R ′)-MNF was inhibited by the β 2 -AR antagonist ICI-118,551 and the protein kinase A inhibitor H-89. The adenylyl cyclase activator forskolin and the phosphodiesterase 4 inhibitor Ro 20-1724 mimicked the ability of ( R , R ′)-MNF to inhibit migration of melanoma cell lines in culture, highlighting the importance of cAMP for this phenomenon. ( R , R ′)-MNF caused significant inhibition of cell growth in β 2 -AR-expressing cells as monitored by radiolabeled thymidine incorporation and xCELLigence system. The MEK/ERK cascade functions in cellular proliferation, and constitutive phosphorylation of MEK and ERK at their active sites was significantly reduced upon β 2 -AR activation with ( R , R ′)-MNF. Protein synthesis was inhibited concomitantly both with increased eEF2 phosphorylation and lower expression of tumor cell regulators, EGF receptors, cyclin A and MMP-9. Taken together, these results identified β 2 -AR as a novel potential target for melanoma management, and ( R , R ′)-MNF as an efficient trigger of anti-tumorigenic cAMP/PKA-dependent signaling in β 2 -AR-expressing lesions. [ABSTRACT FROM AUTHOR]

We report first measurements of ultrafine particles from a semi-rural location, Gadanki, from tropical Southern India. Measurements of particle number size distributions in the diameter range of 5 nm-32 µm were performed during 2 May-31 July 2012. The mean number concentrations of nucleation (NNUC), Aitken (NAIT), accumulation (NACCU), and total particles (NTOT) at this site were (1.1 ± 0.9) x 10³ cm-3, (2.2 ± 1.3) x 10³ cm-3, (1.5 ± 1.2) x 10³ cm-3 and (4.8 ± 2.4) x 10³ cm-3, respectively, comparable to other rural to semi-rural locations globally and declined as the season progressed, perhaps due to wet removal of aerosols with onset of monsoon in early June. Particle bursts in the nucleation mode size range (5-25 nm), followed by a sustained growth in size were observed very rarely (only 5 out of 79 observation days) at this site, less frequently than at most other locations around the world during May-July. Most factors affecting new particle formation (NPF) were similar on NPF and nonNPF event days, such as condensation sink, relative humidity, temperature, wind speed and direction, and mixing layer height. Thus, the infrequent occurrence of NPF at our site appeared to be linked to lower precursor gas concentrations and weak gas-phase oxidation chemistry due to diminished solar radiation on persistently cloudy days with the onset of the monsoon in early June over this region. The derived particle growth rates (GR > 5 nm) and formation rates of 5 nm particles (J5) ranged from 2.2 to 4.7 nm h-1 and 0.4-2.4 cm-3 s-1, with a mean and standard deviation of 3.4 ± 0.9 nm h-1 and 1.2 ± 2.3 cm-3 s-1, respectively, comparable to previous investigations at rural to semi-rural locations. The observed behavior in aerosol and meteorological parameters on NPF and nonNPF event days appeared to be distinctive compared to other rural to urban locations across the globe. However, this distinct behavior is limited and restricted to this site and season of the year, and should therefore not be generalized over a larger spatio-temporal scale. This emphasizes the need for long-term aerosol and precursor measurements over this and other regions of India. [ABSTRACT FROM AUTHOR]

Conversion of waste heat into useful electrical energy employing thermoelectric (TE) technology can improve power generation. However, the synthesis of efficient TE elements is critically challenging in the fabrication of the TE device. In this work, p- and n-type TE elements (single leg) were synthesized by using CoSb 3 skutterudites based optimized compositions (Fe 0·25 Co 0·75 Sb 2·965 Se 0.035 and Ni 0·07 Co 0·93 Sb 2·94 Te 0.06 , respectively), and CoSi 2 has been used as a contact material. The synthesis route of the TE elements is a combination of arc melting and spark plasma sintering, which is a short and cost-effective approach. Synthesized TE elements were characterized for the device performance parameters at different temperature gradients (ΔT), employing a TE conversion efficiency evaluation system (Mini-PEM). The maximum current ∼1.9 A and ∼1.4 A has been drawn, while the maximum output voltage ∼9.8 mV and ∼19 mV was attained by the p- and n-type TE elements, respectively. Finally, the output power has been evaluated, which was found to be ∼5.26 mW at ΔT ∼ 471 °C for p-type TE element, and ∼6.79 mW at ΔT ∼ 465 °C for n-type TE element. [Display omitted] • p- and n-type TE single leg of CoSb 3 based optimized compositions were synthesized. • CoSi 2 has been used as a contact material. • Synthesis route, a combination of arc melting and SPS, is short and cost-effective. • Parameters for single legs were evaluated by Mini-PEM. [ABSTRACT FROM AUTHOR]

Abstract: Rasayana constitutes a very important class of Ayurvedic herbs, which acts as rejuvenators and tonic. Despite intensive research on evaluating the medicinal basis for the purported medical benefits of Rasayana herbs, still a specific chemical guiding principle for the characterization of these herbs in one single category is unclear. Here we explore the possibility that polysaccharides play a key role in Rasayana properties exhibited by medicinal plants. Further on this could be a possible field for exploration for a common factor present in some of the Ayurvedic herbs. The present review covers a literature spanning from 1956 to 2011. Some translations of traditional Ayurvedic texts dating back to the first century AD have been referred to as well. In our assessment of the present literature and studies carried out it is presupposed that the presence of benevolent plant polysaccharides must be one of the important features symbolizing a common effectiveness in most of the Ayurvedic Rasayana herbs. Of the many plant metabolites polysaccharides have not so far been considered and studied effectively compared to other secondary metabolites like saponins, alkaloids, etc. Although all the results reported until now suggest a major contribution of polysaccharide towards the maintenance of physiological homeostasis, which is the guiding principle of Rasayana therapy. The present review is an attempt to find a connective link between the concept of Rasayana and well-being; and the role of plant polysaccharides. Lack of clinical information on number of polysaccharides showing promise is a limiting factor for a complete understanding. It is also important to carry out a molecular interaction study to understand the behavior of polysaccharides discussed in the present review. [Copyright &y& Elsevier]

Summary: Gemcitabine-associated thrombotic thrombocytopenic purpura (TTP) is a rare complication of gemcitabine treatment with a incidence ranging from 0·015% to 1·4%. Clinically, this disease manifests as haemolytic anaemia, thrombocytopenia, and renal insufficiency; hypertension and neurological and pulmonary symptoms are also known complications. The risk of TTP increases as the cumulative dose of gemcitabine approaches 20 000 mg/m2. The pathophysiology of this disease entity is unknown although several theories, involving both immune and non-immune mechanisms, have been proposed. The most effective treatment is discontinuation of gemcitabine, the provision of antihypertensive medications as needed, and consideration of plasmapheresis or use of immunoadsorption column in severe cases. [Copyright &y& Elsevier]

The practical applications of unfilled CoSb 3 -based Skutterudites for thermoelectric (TE) devices have been limited primarily owing to their bipolar conduction behaviour, which is detrimental for the TE performance. In the present studies, a peak TE figure-of-merit (ZT) max ~ 0.7 at 860 K has been realized with a pioneering (ZT) average ~ 0.34 in p-type CoSb 3 co-doped by Fe and Bi at an optimal composition of Fe 0.25 Co 0.75 Sb 2.995 Bi 0.005. The synthesis route for the alloy was the combination of arc melting and the spark plasma sintering. The TE properties measurement results suggest that the Fe doping at the Co site in CoSb 3 lead to the unipolar p-type conduction while Bi substitution at Sb site helps in reducing the thermal conductivity via enhanced point defect induced phonon scattering. The synthesized samples were characterised for phase, morphology and structure using X-ray diffraction, field emission scanning electron microscopy and transmission electron microscopy, based on which some TE properties of the synthesized samples have also been discussed. In addition, the effect of magnetic entropy on the TE performance has also been studied experimentally as well as theoretically. The first-principles based density functional theory has been employed for the theoretical calculation of the electronic band-structure, electrical transport properties and the magnetic moment, which are found to be in fair agreement with the experimental observations. Image 1 • Combination of fast and effective arc melting and the spark plasma sintering was utilized for synthesis. • A peak TE figure-of-merit (ZT) max ~ 0.7 at 860K and pioneering (ZT) average ~ 0.34 are realized for the optimal composition. • The effect of magnetic entropy on the TE performance has also been studied experimentally as well as theoretically. • DFT has been used to calculate electronic band-structure and transport properties coinciding with experimental results. [ABSTRACT FROM AUTHOR]