A thermoelectric power generating heat exchanger: Part I - Experimental realization

An experimental realization of a heat exchanger with commercial thermoelectric generators (TEGs) is presented. The power producing capabilities as a function of flow rate and temperature span are characterized for two different commercial heat transfer fluids and for three different thermal interface materials. The device is shown to produce 2 W per TEG or 0.22 W cm$^{-2}$ at a fluid temperature difference of 175 $^\circ$C and a flow rate per fluid channel of 5 L min$^{-1}$. One experimentally realized design produced 200 W in total from 100 TEGs. For the design considered here, the power production is shown to depend more critically on the fluid temperature span than on the fluid flow rate. Finally, the temperature span across the TEG is shown to be 55% to 75% of the temperature span between the hot and cold fluids.Comment: 9 pages, 11 figure

A Pilot Study on the Association of Lead, 8-Hydroxyguanine, and Malondialdehyde Levels in Opium Addicts’ Blood Serum with Illicit Drug Use and Non-Addict Persons

While a large body of literature has shown the health problems of illicit drug use, research is needed on how substance abuse impacts DNA damage and contaminants in blood, especially given Pb-contaminated opium. This pilot study aimed to evaluate the levels of lead (Pb), 8-hydroxy di-guanine (8-oxo-Gua), and malondialdehyde (MDA) in the blood serum of opium addicts and non-addict people. The current study is a case–control study with a cross-sectional design. A sample of 50 opium-addicted and non-addict adults were chosen for this study using convenience and random sampling methods. Participants were divided into two groups: addicts and non-addicts. The atomic absorption spectroscopy method was used to measure the quantity of Pb, and the Enzyme-Linked Immunosorbent Assay (ELISA) method was used to measure the amount of 8-oxo-Gua and MDA. The data were analyzed using an independent t-test. The results show that the amount of Pb in the blood serum of addicted women and men was higher than levels in non-addict men and women, for the study participants (p-value = 0.001). Blood levels were not significantly different between addicts and non-addicts for men or women for 8-oxo-Gua (p-value = 0.647 for women and p-value = 0.785 for men) and MDA (p-value = 0.867 for women and p-value = 0.995 for men). In general, addicts’ blood Pb levels were found to be substantially higher than those of normal non-addict persons in this pilot study. As a result, testing for blood Pb levels in addicts may be informative in instances when symptoms are inconclusive.</jats:p

Hardware-in-the-loop performance analysis of a railway traction system under sensor faults

Fault mode and effects analysis (FMEA) has been used during decades for analysing the effects of faults in different applications. Initially, FMEA based on risk priority numbers provided information about the effects in the system, but during the last years different approaches have been developed to obtain a more robust risk evaluation. The proposed enhanced FMEA can provide the quantitative effects of sensor faults in a railway traction drive, in variables such as torque, current and voltages. In addition to the previous work, quantitative effects on overall performance indicators, such as energy efficiency and comfort, are obtained too. Hardware-in-the-loop (HIL)-based fault injection approach has been used to generate fault scenarios. The test platform is composed of a real-time simulator and a commercial traction control unit for a railway application

ILSF, A THIRD GENERATION LIGHT SOURCE LABORATORY IN IRAN

Abstract The Iranian Light Source Facility (ILSF) project is a first large scale accelerator facility which is currently under planning in Iran. On the basis of the present design, circumference of the 3 GeV storage ring is 297.6 m. Beam current and natural beam emittance are 400 mA and 3.278 nm.rad respectively. The facility will be built on a land of 50 hectares area in the city of Qazvin, located 150 km West of Tehran. The city is surrounded by many universities, research centers and industrial companies. The design and construction of prototype items such as radio frequency solid state amplifier, dipole magnets, highly stable magnet power supplies and girders have already begun. Site selection studies, including geotechnical and seismological measurements are being performed. Conceptual Design Report, CDR, as the first milestone of the project was published in October 2012

Research priorities for global food security under extreme events

International audienc

HMGA1 Reprograms Somatic Cells into Pluripotent Stem Cells by Inducing Stem Cell Transcriptional Networks

PMC3499526BACKGROUND: Although recent studies have identified genes expressed in human embryonic stem cells (hESCs) that induce pluripotency, the molecular underpinnings of normal stem cell function remain poorly understood. The high mobility group A1 (HMGA1) gene is highly expressed in hESCs and poorly differentiated, stem-like cancers; however, its role in these settings has been unclear. METHODS/PRINCIPAL FINDINGS: We show that HMGA1 is highly expressed in fully reprogrammed iPSCs and hESCs, with intermediate levels in ECCs and low levels in fibroblasts. When hESCs are induced to differentiate, HMGA1 decreases and parallels that of other pluripotency factors. Conversely, forced expression of HMGA1 blocks differentiation of hESCs. We also discovered that HMGA1 enhances cellular reprogramming of somatic cells to iPSCs together with the Yamanaka factors (OCT4, SOX2, KLF4, cMYC - OSKM). HMGA1 increases the number and size of iPSC colonies compared to OSKM controls. Surprisingly, there was normal differentiation in vitro and benign teratoma formation in vivo of the HMGA1-derived iPSCs. During the reprogramming process, HMGA1 induces the expression of pluripotency genes, including SOX2, LIN28, and cMYC, while knockdown of HMGA1 in hESCs results in the repression of these genes. Chromatin immunoprecipitation shows that HMGA1 binds to the promoters of these pluripotency genes in vivo. In addition, interfering with HMGA1 function using a short hairpin RNA or a dominant-negative construct blocks cellular reprogramming to a pluripotent state. CONCLUSIONS: Our findings demonstrate for the first time that HMGA1 enhances cellular reprogramming from a somatic cell to a fully pluripotent stem cell. These findings identify a novel role for HMGA1 as a key regulator of the stem cell state by inducing transcriptional networks that drive pluripotency. Although further studies are needed, these HMGA1 pathways could be exploited in regenerative medicine or as novel therapeutic targets for poorly differentiated, stem-like cancers.JH Libraries Open Access Fun

Quality of working life and organizational commitment of Iranian pre-hospital paramedic employees during the 2019 novel coronavirus outbreak

The present study aims to examine the relationship between the quality of working life and organizational commitment of prehospital paramedic personnel in Emergency Medical Systems affiliated to the Kerman University of Medical Sciences, Iran during the COVID-19 pandemic. A cross-sectional study was conducted in 2020, in 12 emergency bases supervised by Kerman University of Medical Sciences and 200 participants were randomly selected according to the table of Morgan. Meyer and Allen's organizational commitment questionnaires and Bolton's quality of working life questionnaire were used in the study. Normative commitment component among other organizational commitment components had the highest mean score, 3.51 ± 1.06 and emotional commitment component had the lowest average, 3.31 ± 0.83. Among the factors of working life quality, the skill development opportunities and continuous learning had the highest mean score, 3.37 ± 0.87 and the wage and material benefits component had the lowest average, 1.65 ± 1.08. There was a significant relationship between the organizational commitment and quality of working life P = 0.01, r = 0.45. According to the results of the present research, to increase the quality of working life and organizational commitment of Emergency Medical personnel, more emphasis should be placed on the employee participation in terms of decision-making, skill development opportunities, continuous learning and job security. © 2020 Informa UK Limited, trading as Taylor & Francis Group

Evaluation of global digital elevation model for flood risk management in Perlis

In flood modelling process, Digital Elevation Models (DEMs) is a valuable tool in topographic parameterization of hydrological models. The release of the free-of-charge satellite based DEMs such as SRTM and ASTER prompted the accurate flood modelling process especially to propose flood mitigation in the Perlis region. In this research, the accuracy of SRTM DEM of spatial resolution 1 arc-sec and 3 arc-sec, as well as ASTER DEM are evaluated. The reference levels produced from GNSS observation and Earth Gravitational Model 1996 (EGM96), as well as local mean sea level are used to analyse the vertical accuracy of each GDEMs in Perlis, Malaysia. The total of 38 Benchmark (BM) and Standard Benchmark (SBM) around the Perlis region were observed by GNSS using static method and processed using TOPCON Tool software. A comparison with the local mean sea level height indicated that SRTM 1″ is the much greater absolute vertical accuracy with an RMSE of ±3.752 m and continued by SRTM 3″ and ASTER GDEMs where the obtained accuracy was ±4.100 and ±5.647 m, respectively. Also, by using orthometric height form the GNSS and EGM96 as reference elevation, the obtained accuracy was ±3.220, ±3.597, and ±5.832 m for SRTM 1″, SRTM 3″ and ASTER, respectively. Statistical results have also shown that SRTM 1″ has a good correlation with Hmsl and HGNSS where both correlations values are 0.9925, while the SRTM 3″ and ASTER show the correlation of 0.9873 and 0.9375

Copy Number Alterations and Neoplasia-Specific Mutations in MELK, PDCD1LG2, TLN1, and PAX5 at 9p in Different Neoplasias

Genetic alterations affecting 9p are commonly present in many cancer types and many cancer-related genes are located in this chromosomal region. We sequenced all of the genes located in a 32Mb region of 9p by targeted next generation sequencing (NGS) in 96 patients with different cancer types, including acute lymphoblastic leukemia, bone malignant fibrous histiocytoma/undifferentiated pleomorphic sarcoma, fibrosarcoma, Ewing's sarcoma, and lung carcinoma. Copy number alterations (CNA), and mutations were studied from the NGS data. We detected a deletion at the CDKN2A locus as being the most frequent genetic alteration in all cancer types. In addition to this locus, NGS also identified other small regions of copy number loss and gain. However, different cancer types did not reveal any statistically significant differences with regard to CNA frequency or type. Of the 191 genes within the target region, two novel recurrent mutations were found in the MELK and PDCD1LG2 genes. The most commonly mutated gene in sarcomas was TLN1 (8%) and PAX5 in ALL (9%). Mutations in PAX5, and RUSC2, were seen exclusively in ALL patients and those in KIAA1432, CA9, TLN1, and MELK only in sarcomas (MFH, FS, EFT). Thus using targeted NGS of the 9p region, in addition to commonly deleted CDKN2A locus, we were able to identify a number of small deletions and gains, as well as novel recurrent mutations in different cancer types. (c) 2014 Wiley Periodicals, Inc