High thermoelectric figure of merit, zT, of ~1.85 at 725 K along with significant cyclable temperature stability was achieved in Pb-free p-type Ge 1-x Sb x Te samples through simultaneous enhancement in Seebeck coefficient and reduction of thermal conductivity. Sb doping in GeTe decreases the carrier concentration due to the donor dopant nature of Sb and enhances the valence band degeneracy by increasing the cubic nature of the sample, which collectively boost Seebeck coefficient in the temperature range of 300-773 K.Significant thermal conductivity reduction was achieved due to collective phonon scattering from various meso-structured domain variants, twin and inversion boundaries, nanostructured defect layers, and solid solution point defects. The high performance Ge 0.9 Sb 0.1 Te sample shows mechanical stability (Vickers microhardness) of ~206 H v , which is significantly higher compared to other popular thermoelectric materials such as Bi 2 Te 3 , PbTe, PbSe, Cu 2 Se and TAGS.

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Spinel ferrite NiFe O thin films have been grown on three isostructural substrates, MgAl O , MgGa O , and CoGa O using pulsed laser deposition. These substrates have lattice mismatches of 3.1%, 0.8%, and 0.2%, respectively, with NiFe O . As expected, the films grown on MgAl O substrate show the presence of the antiphase boundary defects. However, no antiphase boundaries (APBs) are observed for films grown on near-lattice-matched substrates MgGa O and CoGa O . This demonstrates that by using isostructural and lattice-matched substrates, the formation of APBs can be avoided in NiFe O thin films. Consequently, static and dynamic magnetic properties comparable with the bulk can be realized. Initial results indicate similar improvements in film quality and magnetic properties due to the elimination of APBs in other members of the spinel ferrite family, such as Fe O and CoFe O , which have similar crystallographic structure and lattice constants as NiFe O .

High Thermoelectric Performance and Enhanced Mechanical Stability of p-Type Ge 1-xSbxTe. -Ge1-xSbxTe (x = 0-0.1) is prepared from the elements (evacuated quartz tubes, 1223 K, 6 h). The material crystallizes in the rhombohedral space group R3m (powder XRD), but shows an increasing cubic nature with Sb doping. A maximum thermoelectric figure of merit of 1.85 at 725 K is achieved for x = 0.1 along with a high temperature stability in heating/cooling cycles. The results are achieved through simultaneous enhancement of the Seebeck coefficient and reduction of thermal conductivity, the former by decreasing the carrier concentration due to the donor dopant nature of Sb which enhances the valence band degeneracy by increasing the cubic nature of the sample, the latter by collective phonon scattering from various meso-structured domain variants, twin and inversion boundaries, nanostructured defect layers, and solid solution point defects. The high performance Ge 0.9Sb0.1Te sample shows a mechanical stability (Vickers microhardness of 206 H v) which is significantly higher compared to other popular thermoelectric materials such as Bi 2Te3, PbTe, PbSe, or Cu2Se.

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Prostate cancer (PCa) is a common illness for aging males. Lycopene has been identified as an antioxidant agent with potential anticancer properties. Studies investigating the relation between lycopene and PCa risk have produced inconsistent results. This study aims to determine dietary lycopene consumption/circulating concentration and any potential dose–response associations with the risk of PCa. Eligible studies published in English up to April 10, 2014, were searched and identified from Pubmed, Sciencedirect Online, Wiley online library databases and hand searching. The STATA (version 12.0) was applied to process the dose–response meta-analysis. Random effects models were used to calculate pooled relative risks (RRs) and 95% confidence intervals (CIs) and to incorporate variation between studies. The linear and nonlinear dose–response relations were evaluated with data from categories of lycopene consumption/circulating concentrations. Twenty-six studies were included with 17,517 cases of PCa reported from 563,299 participants. Although inverse association between lycopene consumption and PCa risk was not found in all studies, there was a trend that with higher lycopene intake, there was reduced incidence of PCa (P = .078). Removal of one Chinese study in sensitivity analysis, or recalculation using data from only high-quality studies for subgroup analysis, indicated that higher lycopene consumption significantly lowered PCa risk. Furthermore, our dose–response meta-analysis demonstrated that higher lycopene consumption was linearly associated with a reduced risk of PCa with a threshold between 9 and 21 mg/day. Consistently, higher circulating lycopene levels significantly reduced the risk of PCa. Interestingly, the concentration of circulating lycopene between 2.17 and 85 μg/dL was linearly inversed with PCa risk whereas there was no linear association >85 μg/dL. In addition, greater efficacy for the circulating lycopene concentration on preventing PCa was found for studies with high quality, follow-up >10 years and where results were adjusted by the age or the body mass index. In conclusion, our novel data demonstrates that higher lycopene consumption/circulating concentration is associated with a lower risk of PCa. However, further studies are required to determine the mechanism by which lycopene reduces the risk of PCa and if there are other factors in tomato products that might potentially decrease PCa risk and progression.

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