248 research outputs found

    Surficial and vertical distribution of heavy metals in marine and intertidal sediments in the Iranian sector of Gowatr bay

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    In order to identify natural and anthropogenic pollution in Gowatr bay (also gowadar bay), the distribution of heavy metals in the surface and different depths of marine and intertidal sediments was studied. For this purpose, 17 surficial sediment samples, and 5 sediment cores were collected, and compared with local background concentration. The results of surficial distribution of heavy metals indicate that maximum concentration of Copper and Zinc, Lead, and Nickel is related to Pasabandar harbor, sandy coast, and mudflats of Mangrove jungle, respectively. Calculated correlation coefficients indicate good positive correlation between Iron, clay fraction and potentially toxic metals, especially; Cu, Zn, Pb and Ni. Heavy metals distribution at depth was determined in five sediment cores. Sixty percent of sediment cores display surficial Pb enrichment, while Ni and Co are concentrated at depth. According to geo-accumulation factor (Igeo), zinc and copper show heavy contamination in Pasabandar harbor. Maximum PLI and RI are also related to Pasabandar harbor. Marine traffic, and ship yards activity at and close to Pasabandar harbor and mangrove jungle, along with weathering of ophiolites are apparently responsible for the observed elevated concentration of heavy metals in Gowatr bay

    Microplastics in different tissues of fish and prawn from the Musa Estuary, Persian Gulf.

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    Commercially-important species of fish and a crustacean from four sites in the Musa estuary and a site in the Persian Gulf have been analysed for the presence and location of microplastics (MPs). A total of 828 MPs were detected in the guts (gastrointestinal tracts), skin, muscle, gills and liver of demersal and pelagic fish (Platycephalus indicus, Saurida tumbil, Sillago sihama, Cynoglossus abbreviatus) from all five sites and in the exoskeleton and muscle of the tiger prawn, Penaeus semisulcatus, from three sites. On an individual basis, MPs were most abundant in P. indicus (mean = 21.8) and least frequently encountered in P. semisulcatus (mean = 7.8), but when normalized on a mass basis, MPs ranged from 0.16 g-1 for C. abbreviatus to 1.5 g-1 for P. semisulcatus. Microscopic analyses (polarized light, fluorescence, SEM/EDS) revealed that MPs were mainly fibrous fragments (with a few angular fragments) of various colour and size ( 1000 μm) and with strong C and O signatures. Additional particles detected that were distinctly different in colour, morphology, brittleness and elemental composition (part-metallic, and containing Cu) were suspected of being fragments of antifouling paint. The means of entry of MPs into tissues not involved in digestion are unclear but could be related to translocation or adherence. Regardless of the mode of accumulation, the presence of MPs in heavily fished species of fish and crustacean raises concerns about the potential transfer of synthetic materials into humans

    Accuracy of endoscopic ultrasonography for determination of tumor invasion depth in gastric cancer

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    Background: Gastric cancer (GC) is one the common lethal cancers in Iran. Detection of GC in the early stages would assesses to improve the survival of patients. In this study, we attempt to evaluate the accuracy of EUS in detection depth of invasion of GC among Iranian Patients. Materials and Methods: This study is a retrospective study of patients with pathologically confirmed GC. They underwent EUS before initiating the treatment. The accuracy of EUS and agreement between the two methods was evaluated by comparing pre treatment EUS finding with post operative histopathological results. Results: The overall accuracy of EUS for T and N staging was 67.9 and 75.47, respectively. Underestimation and overestimation was seen in 22 (14.2) and 40 (25.6) respectively. The EUS was more accurate in large tumors and the tumors located in the middle and lower parts of the stomach. The EUS was more sensitive in T3 staging. The values of weighted Kappa from the T and N staging were 0.53 and 0.66, respectively. Conclusions: EUS is a useful modality for evaluating the depth of invasion of GC. The accuracy of EUS was higher if the tumor was located in the lower parts of the stomach and the size of the tumor was more than 3 cm. Therefore, judgments made upon other criteria evaluated in this study need to be reconsidered

    Lead-Free Perovskite-Inspired Absorbers for Indoor Photovoltaics

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    With the exponential rise in the market value and number of devices part of the Internet of Things (IoT), the demand for indoor photovoltaics (IPV) to power autonomous devices is predicted to rapidly increase. Lead-free perov skite-inspired materials (PIMs) have recently attracted significant attention in photovoltaics research, due to the similarity of their electronic structure to high-performance lead-halide perovskites, but without the same toxicity limitations. However, the capability of PIMs for indoor light harvesting has not yet been considered. Herein, two exemplar PIMs, BiOI and CsSbClxI-x are examined. It is shown that while their bandgaps are too wide for single-junction solar cells, they are close to the optimum for indoor light harvesting. As a result, while BiOI and CsSbClxI-x devices are only circa %-ecient under -sun illumination, their eciencies increase to –% under indoor illumination. These eciencies are within the range of reported values for hydrogenated amorphous silicon, i.e., the industry standard for IPV. It is demonstrated that such performance levels are already sucient for millimeter-scale PIM devices to power thin-film-transistor circuits. Intensity-dependent and optical loss analyses show that future improvements in eciency are possible. Furthermore, calculations of the optically limited eciency of these and other low-toxicity PIMs reveal their considerable potential for IPV, thus encouraging future eorts for their exploration for powering IoT devic

    Salivary nitric oxide levels in adults with different DMFT scores in a selected iranian population: a cross-sectional study

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    Objectives: Due to the emphasis on the protective and antimicrobial role of Nitric Oxide against gas-trointestinal diseases, investigating its relationship with dental caries is a right topic. Therefore, this research has investigated the amount of saliva Nitric Oxide in different volumes of DMFT indicator in adults. Material and Methods: In this descriptive-analytical cross-sectional study, 80 participants (20-35 years old), without a history of systemic disease and drug use participated as research sam-ples, (53.8% of the participants in the study were women). Participants were selected from patients who had visited dental Department. The participants were divided in four groups based on DMFT (DMFT=0, 1≤DMFT≤3, 3<10, DMFT≥10). Non-stimulating saliva was collected from all participants between 9-11 am in a calibrated tube. Saliva Nitric Oxide was measured using a Nitrous Oxide test, based on the Griess reaction. We used a correlation test to analyze quantitative variables, and t-test or ANOVA for qualitative and quantitative variables. Results: A significant relationship between DMFT and age was identified. At different levels of DMFT, significant relationship between DMFT and sex was not found. In different groups of DMFT, no significant relationship between Nitric Oxide and DMFT exist. Conclusion: The level of Nitric Oxide saliva was not affected by the amount of DMFT

    An interdisciplinary framework for Islamic cognitive theories

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    The Islamic psychology (IP) community in Europe has recently witnessed a heated debate about the credentials required to participate in the theoretical substantiation of IP and Islamically integrated psychotherapy and counseling. This debate has provided convenient circumstances for Muslim psychologists and Islamic scholars alike to rethink their roles within the flourishing movement. Specifically, the discussions hint toward the importance of adopting a collaborative research methodology for IP, in particular for basic research. The methodology of choice will need to define the necessary qualifications and responsibilities of scholars and psychologists in a collaborative research process (personal collaboration) and evince its capability to appropriately marry knowledge and data, diverging research methods, and perspectives, concepts, and theories from Islamic studies and contemporary psychology (content-related collaboration). Here, we devise and offer a case illustration of an Islamic Psychology Basic Research Framework (coined the SALAAM Framework). This framework uses the Institute for Interdisciplinary Studies (IIS) Model of Interdisciplinary Research, developed by the IIS at the University of Amsterdam. Our first aim is to appropriate the IIS model for the IP literature by applying the model's research process phases and technique for the integration of disparate bodies of knowledge—that is, the identification of common ground—to methodological approaches in the contemporary IP literature. Our second aim is to exemplify the devised SALAAM Framework using the relatively unexplored area of Islamic cognitive theories (ICTs), which remain underdeveloped in contemporary psychological literature, primarily because of a lack of commensurability with the nomenclature of contemporary psychology. We thus provide a primer on the potential scope of ICTs. Toward the end of this article, we discuss the potential of the project of interdisciplinary construction of Islamic psychological theory, and the ability of the SALAAM Framework to establish a research program in IP that centers on cognition. We finally offer our reflections on the distinctiveness of Islamic psychologies in comparison to mainstream and Christian psychology.Q4WOS:0004589189000062-s2.0-8506156876
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