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Summary We demonstrate early progress toward constructing a high-throughput, single-molecule protein sequencing technology utilizing barcoded DNA aptamers (binders) to recognize terminal amino acids of peptides (targets) tethered on a next-generation sequencing chip. DNA binders deposit unique, amino acid-identifying barcodes on the chip. The end goal is that, over multiple binding cycles, a sequential chain of DNA barcodes will identify the amino acid sequence of a peptide. Toward this, we demonstrate successful target identification with two sets of target-binder pairs: DNA-DNA and Peptide-Protein. For DNA-DNA binding, we show assembly and sequencing of DNA barcodes over six consecutive binding cycles. Intriguingly, our computational simulation predicts that a small set of semi-selective DNA binders offers significant coverage of the human proteome. Toward this end, we introduce a binder discovery pipeline that ultimately could merge with the chip assay into a technology called ProtSeq, for future high-throughput, single-molecule protein sequencing., Graphical abstract, Highlights • Designed ProtSeq protein sequencing method compatible with widely used NGS technology • Built Target-Switch SELEX to isolate aptamers specific to N-terminal amino acids (AAs) • Showed binding, ligation, cleavage, and NGS of six DNA binders in ordered barcode chain • Developed pipeline to deconvolve AAs from DNA barcodes to identify putative proteins, Biochemistry; Biochemistry applications; Sequence analysis; Proteomics; Transcriptomics

The aim of the current study was to synthesize polyvinyl alcohol Cuprous Oxide composite films (PVA/Cu2O) for radiation detection depending on optical changes. The method adapted from solving of 5% PVA in hot (80 °C) stirred water and after cooling to ambient temperature a 0.5 g of Cu2O dissolved and stirred for 2 h. The films were made by casting in petri dishes contained 20 ml/each. The pealed films were enveloped after drying and receiving radiation doses of 1, 2, 4, 6 … 12 Gy. The analysis revealed a gradient change in color of films from light pink to dark brown with absorption peaks at 215 and 415 nm through entire doses which were increase as dose increment. The optical density of films increases linearly and significantly (R2 = 0.9) as the dose increases from 0.06 (arb. unit) at 1 Gy to 0.4 (a u) at 12 Gy with sensitivity at 0.06 mGy. The energy band gap of the film decreased as the radiation dose increases from 3 × 10−12 to 2 × 10−12 eV. Conclusively; the feasibility of utilizing PVA/Cu2O composite films as radiation detector and personal dosimeter would be applicable in rural sectors and low economic countries. Keywords: PVA, Films, Dosimeters, Cuprous, Radiation, Optical

This work reports the enhancement of thermoelectric properties of La0.5Co4Sb12 compound due to addition of Al. A polycrystalline AlxLa0.5Co4Sb12 (0 ​≤ ​x ​≤ ​0.5) skutterudites were successfully prepared by mechanical alloying and spark plasma sintering techniques. The characterization of phase structure and morphology of AlxLa0.5Co4Sb12 bulk samples are examined by XRD and SEM-EDX analysis. The results revealed that the main phase of CoSb3 skutterudite structure with a small amount of Al were distributed in the grain boundaries for the most of AlxLa0.5Co4Sb12 samples. The thermoelectric measurements of consolidated samples were evaluated from room temperature to 800 ​K. The electrical resistivity remarkably reduced through the addition of Al to the lowest value of 7.6 ​μΩm at room temperature for Al0.05La0.5Co4Sb12 sample. Moreover, the absolute Seebeck coefficient was significantly improved by Al addition and the highest value of 193 ​μV/K was observed at 789 ​K for Al0.05La0.5Co4Sb12 sample. Furthermore, the same formulation showed a significant enhancement on the power factor that reached the maximum value of 4.02 ​× ​10−3 ​W/mK2 at 789 ​K. The thermal conductivity and lattice thermal conductivity were significantly minimized to the value of 1.1 ​W/mK (at 789 ​K) and 0.64 ​W/mK (at 595 ​K), respectively for Al0.3La0.5Co4Sb12 due to the enhancement of phonon scattering. Additionally, a comprehensive improvement on the dimensionless figure of merit value ZT of 1.36 for Al0.05La0.5Co4Sb12 at 789 ​K has been achieved.

The present study focuses on coarsening of Ag3Sn intermetallic compound in the Sn-1Ag-0.5Cu and Fe-modified Sn-1Ag-0.5Cu solder alloy. The investigations showed that the Ag3Sn intermetallics coarsened rapidly in the Sn-1Ag-0.5Cu solder alloy whereas the Ag3Sn intermetallics were found to be quite stable in the Fe-modified Sn-1Ag-0.5Cu solder alloy. The lattice strain in the Ag3Sn intermetallics and the blocking effect on Ag diffusivity in Sn matrix suggested the possible mechanisms for the coarsening suppression of the Ag3Sn intermetallics in the Fe-modified solder alloy. (C) 2014 Elsevier B.V. All rights reserved.

Thermoelectric generators (TEGs) have been identified as a viable technology for waste energy harvesting, from heat into electricity. Key to successful realization of this technology on a commercial scale lies largely with the thermoelectric material which drives this technology. While bismuth telluride based TEGs dominate the current market, liabilities such as toxicity, depletion of raw resources and high production costs have triggered the search for alternative thermoelectric materials. One of the contenders as thermoelectric materials in the mid-temperature range is the family of Mg–Mn silicides, given the advantages of abundance of raw resources, relatively high thermoelectric performance, lowered production costs, and environmental compatibility. In this paper, the thermoelectric performance of this class of materials is first reviewed through the key thermoelectric parameters: thermal and electrical conductivity, Seebeck coefficient and power factor. The development fabrication processes for this class of materials, using nanostructuring and element doping strategies, are then elaborated. Finally, comments on the thermoelectric applications and device efficiency are made within the context of this material.

Developing thermoelectric materials with superior performance means tailoring interrelated thermoelectric physical parameters – electrical conductivities, Seebeck coefficients, and thermal conductivities – for a crystalline system. High electrical conductivity, low thermal conductivity, and a high Seebeck coefficient are desirable for thermoelectric materials. Therefore, knowledge of the relation between electrical conductivity and thermal conductivity is essential to improve thermoelectric properties. In general, research in recent years has focused on developing thermoelectric structures and materials of high efficiency. The importance of this parameter is universally recognized; it is an established, ubiquitous, routinely used tool for material, device, equipment and process characterization both in the thermoelectric industry and in research. In this paper, basic knowledge of thermoelectric materials and an overview of parameters that affect the figure of merit ZT are provided. The prospects for the optimization of thermoelectric materials and their applications are also discussed.

The variables: age, income, education, number of children, and a dichotomous dummy variable for nationality were used to explain the consumption behavior of dairy products: fresh milk, butter, cheese, yoghurt, powdered milk, condensed milk, cream, and ice cream in the urban centers of Al-ain, Dubai, and Abu Dhabi. Results suggest different determinants for consumption behaviors of nationals and expatriates as well as different determinants along the income range of the sample. Estimates for the expenditure elasticity were relatively higher for lower income groups when unreported income is taken into consideration in interpreting the results. Differences in consumption behavior bear an important implication to marketing and promotion of dairy products: different strategies that incorporate the different consumption determinants are perhaps necessary for the different ethnic groups.

Background Hepatitis B virus (HBV) infection is a global public health problem. It is estimated that there are more than 300 million HBV carriers in the world. Aim The study aimed to examine the sero-prevalence of hepatitis B virus (HBV) markers among health care workers (HCWs) in Public Teaching Hospitals in Khartoum State, in the year 2004. Methods The study is an observational, cross sectional, facility-based study. It was conducted on stratified two-stage cluster random sample of 843 subjects. The study followed non-parametric statistical methods, using Z -test for single proportion. Results Among the 843 subjects tested for all HBV markers (Anti-HBc, HBsAg, HBsAb, and HBeAg), the prevalence of Anti-HBc, HBsAg, HBsAb, and HBeAg was found to be 57% (CI 95%:53–60%), 6% (CI 95%:4.0–8.0%), 37% (CI 95%:34–40%) and 9% (CI 95%:7–11%) respectively. P Conclusion Seroprevalence of all HBV markers ( P

Hepatitis C virus (HCV) replication is dependent on a liver-specific microRNA (miRNA), miR-122. A recent clinical trial reported that transient inhibition of miR-122 using locked nucleic acid (LNA) oligonucleotides reduced viral titers in HCV infected patients. Though viral resistance was not reported, the transient nature of these studies makes it unclear whether HCV can evolve resistance to miR-122 inhibition. To address this important question, we generated liver cells in which miR-122 was stably inhibited using a lentiviral vector-based miR-122 decoy.Strikingly, after 20 days in culture we observed the emergence of an HCV variant that was resistant to miR-122 knockdown. Deep-sequencing of the resistant virus revealed that this was due to a single nucleotide change at position 28 (G28A) of the HCV genome, which falls between the two miR-122 seed-binding sites in the virus. We could recapitulate resistance into a wildtype virus by introducing the G28A mutation, which confirmed that this single nucleotide change was responsible. We also found that the G28A mutation makes HCV similarly resistant to miR-122 knockdown by LNA. Importantly, HCV isolates that were innately G28A were similarly resistant to miR-122 inhibition by miR-122 decoy and LNA, indicating that our findings apply to natural strains of the virus, and to inhibition using oligonucleotides.To better understand the mechanism by which G28A confers resistance, we precisely quantitated both wild-type and mutant virus miR-122 stoichiometric requirements. Our results indicate that in the presence of excess miR-122 to viral genomes, there was no difference in target site interaction. Instead, when the bioavailable concentration of miR-122 become rate-limiting, the G28A target site became preferentially regulated. These results indicate that target site selection is strongly influenced by microRNA concentration, and demonstrate that subtle differences in viral sequence, even outside the seed-binding site, greatly affect HCV's miR-122 concentration requirement.This study provides insight into the interaction between miR-122 and HCV, including viral adaptation to reduced miR-122 bioavailability, and has broader implications for the development and use of microRNA-based drugs and for our understanding of microRNA target site selection.