60 research outputs found

    Bioaccumulation of heavy metals Cu, Zn, and Hg in muscles and liver of the stellate sturgeon (Acipenser stellatus) in the Caspian Sea and their correlation with growth parameters

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    Bioaccumulation of Cu, Zn, Hg in muscles and liver tissues of stellate sturgeon (Acipenser stellatus) from the southern Caspian Sea was measured. Effects of condition factor (CF), age and hepatosomatic index (HSI) on metal accumulation were also determined. Some 40 stellate sturgeons were collected using gill nets in winter and spring 2007-2008 from the southern shores of the Caspian Sea. Total (TL) and fork (FL) length and weight of all specimens were measured. Cross sections of first ray of pectoral fins were used for age determination. Muscle and liver samples were taken and transported to the laboratory in ice packs and kept in -20 °C prior to analyses. In the laboratory samples were oven dried, digested with HClO3 and HNO3 and diluted with dionized water to 50cc to measure Cu, Zn, and Hg concentration with a flame spectrophotometer. Sequence of metals in Acipenser stellatus was Zn>Hg> Cu in muscle tissues and Zn>Cu>Hg in liver samples. Concentration of Zn was slightly in correlation with age (R= 0.3). A negative correlation was observed between Zn concentrations with condition factor (R = -0.3). Zn concentrations were negatively correlated in muscle tissues (R = -0.3). The results were compared to international standards proposed by MAAF, EEC and NHMRC. Our study showed that accumulation of heavy metals in sturgeon tissues was influenced by concentration of metals in sediment and the physiological state of fish

    Concentration of heavy and toxic metals Cu, Zn, Cd, Pb and Hg in liver and muscles of Rutilus frisii kutum during spawning season with respect to growth parameters

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    Concentration of heavy and toxic metals Cu, Zn, Cd, Pb and Hg were determined in liver and muscles of Rutilus frisii kutum and their relationships with growth parameters (length, age, condition factor) and hepatosomatic index were examined. Thirty-six fish samples were collected from February through March 2009 caught by beach seine in the southwest parts of the Caspian Sea. Atomic absorption and Hg determined concentrations of Cd, Pb, Zn and Cu by vapor method. Cadmium was recorded only in liver samples. Range of other metals in muscle tissue were ND-0.591, 0.001-0.013, 11-26 and 0.729-7.261 µg/g dw for Pb, Hg, Zn and Cu respectively. Highest levels of Pb, Zn, and Cu were recorded in muscles Hg and Cd in liver samples. Growth parameters showed a significant relationship with Zn and Cd concentrations in liver samples and only Zn concentrations in muscle samples. There was a positive significant correlation between concentration of Cd in liver and physiological indices (p<0.05). Although higher concentration of Pb was recorded in this study in comparison to previous studies, based on Provisional Tolerable Weekly and daily Intake of fish for human health, kutum is considered safe for human consumption. Considering the results of this study it seems reproductive status of the fish influences heavy metals concentration in liver and muscles of kutum and therefore concentrations of some metals such as Zn and Cu in liver samples may not be a reliable bioindicator for environmental pollution

    Heavy metals Cu, Zn, Cd and Pb in tissue, liver of Esox lucius and sediment from the Anzali international lagoon- Iran

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    Levels of contaminants in fish are of particular interest because of the potential risk to humans consuming them. This paper examines the levels of cadmium, lead, zinc and copper in liver and muscle tissue of Esox lucius and in sediments from the Anzali international wetland in Iran. The wetland is a nursery and feeding habitat for fish species both from the lagoon and the Caspian Sea, which are consumed by the local inhabitants and others. Eleven main rivers discharge agricultural, industrial, urban and municipal wastes into this wetland. Twenty five Esox lucius specimens, with a mean weight of 804.6±121g and mean length of 430.7± 2mm were collected from the wetland by multi mesh gill nets in September and December 2007.. The age was determined from scale samples according to the annual ring structure. Average concentrations of Cd, Cu, Pb and Zn accumulated in the mid-dorsal muscle tissue (filleted and skinned) of fish were 0.001, 0.21±0.02, 0.13±0.01 and 2.55±0.18 µg.g-1, respectively. The concentrations of these metals in liver samples were Cd: 0.0014± Cu: 0.96± 0.61, Pb: 0.11 ± 0.04 and Zn: 2.46±1.5 µg.g-1. Significant positive correlations were detected between Zn and Cu with body weight, while negative correlations were found between Pb and body weight. The concentrations of Zn, Cu and Cd were below the maximum allowable concentrations for fish proposed by WHO and MAFF (safe for human consumption) but concentration of Pb exceeded the standard levels

    The Nekton Maldives taxonomic workshop: Exploring the biodiversity of shallow, mesophotic and deep-sea communities in Maldives

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    This is the final version. Available from Pensoft Publishers via the DOI in this record. The Nekton Maldives Taxonomic Workshop took place at the Maniyafushi Research Station in the Maldives between 12 and 23 February 2023. This workshop had two primary objectives. Firstly, it aimed to identify species from biological samples and underwater imagery collected during the Nekton Maldives Mission in 2022. Secondly, it sought to facilitate training and knowledge exchange sessions between early career researchers from the Maldives and international taxonomists. These sessions were designed to share knowledge and introduce fundamental taxonomy concepts and enhance practical identification skills for common reef benthic groups and major zooplankton taxonomic groups. A total of 24 people from 10 different countries were directly or indirectly involved with the workshop comprising nine taxonomic experts, eleven trainees and four organisers. Collectively, we identified 278 biological specimens including potentially undescribed species of hydroids, black corals, sponges and octocorals, 318 morphotypes for underwater footage and zooplankton composition congruent with previous reports from the Indian Ocean Region. Next steps will involve depositing the specimens into a more a permanent facility to facilitate the process of specimen description and knowledge transfer.Nekton FoundationMaldives Marine Research Institut

    Prevalence and molecular characterization of Glucose-6-Phosphate dehydrogenase deficient variants among the Kurdish population of Northern Iraq

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    <p>Abstract</p> <p>Background</p> <p>Glucose-6-Phosphate dehydrogenase (G6PD) is a key enzyme of the pentose monophosphate pathway, and its deficiency is the most common inherited enzymopathy worldwide. G6PD deficiency is common among Iraqis, including those of the Kurdish ethnic group, however no study of significance has ever addressed the molecular basis of this disorder in this population. The aim of this study is to determine the prevalence of this enzymopathy and its molecular basis among Iraqi Kurds.</p> <p>Methods</p> <p>A total of 580 healthy male Kurdish Iraqis randomly selected from a main regional premarital screening center in Northern Iraq were screened for G6PD deficiency using methemoglobin reduction test. The results were confirmed by quantitative enzyme assay for the cases that showed G6PD deficiency. DNA analysis was performed on 115 G6PD deficient subjects, 50 from the premarital screening group and 65 unrelated Kurdish male patients with documented acute hemolytic episodes due to G6PD deficiency. Analysis was performed using polymerase chain reaction/restriction fragment length polymorphism for five deficient molecular variants, namely G6PD Mediterranean (563 C→T), G6PD Chatham (1003 G→A), G6PD A- (202 G→A), G6PD Aures (143 T→C) and G6PD Cosenza (1376 G→C), as well as the silent 1311 (C→T) mutation.</p> <p>Results</p> <p>Among 580 random Iraqi male Kurds, 63 (10.9%) had documented G6PD deficiency. Molecular studies performed on a total of 115 G6PD deficient males revealed that 101 (87.8%) had the G6PD Mediterranean variant and 10 (8.7%) had the G6PD Chatham variant. No cases of G6PD A-, G6PD Aures or G6PD Cosenza were identified, leaving 4 cases (3.5%) uncharacterized. Further molecular screening revealed that the silent mutation 1311 was present in 93/95 of the Mediterranean and 1/10 of the Chatham cases.</p> <p>Conclusions</p> <p>The current study revealed a high prevalence of G6PD deficiency among Iraqi Kurdish population of Northern Iraq with most cases being due to the G6PD Mediterranean and Chatham variants. These results are similar to those reported from neighboring Iran and Turkey and to lesser extent other Mediterranean countries.</p

    Molecular characterization of glucose-6-phosphate dehydrogenase deficient variants in Baghdad city - Iraq

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    Background: Although G6PD deficiency is the most common genetically determined blood disorder among Iraqis, its molecular basis has only recently been studied among the Kurds in North Iraq, while studies focusing on Arabs in other parts of Iraq are still absent. Methods: A total of 1810 apparently healthy adult male blood donors were randomly recruited from the national blood transfusion center in Baghdad. They were classified into G6PD deficient and non-deficient individuals based on the results of methemoglobin reduction test (MHRT), with confirmation of deficiency by subsequent enzyme assays. DNA from deficient individuals was studied using a polymerase chain reaction-Restriction fragment length polymorphism (PCR-RFLP) for four deficient molecular variants, namely G6PD Mediterranean (563 C®T), Chatham (1003 G®A), A- (202 G®A) and Aures (143 T®C). A subset of those with the Mediterranean variant, were further investigated for the 1311 (C®T) silent mutation. Results: G6PD deficiency was detected in 109 of the 1810 screened male individuals (6.0%). Among 101 G6PD deficient males molecularly studied, the Mediterranean mutation was detected in 75 cases (74.3%), G6PD Chatham in 5 cases (5.0%), G6PD A- in two cases (2.0%), and G6PD Aures in none. The 1311 silent mutation was detected in 48 out of the 51 G6PD deficient males with the Mediterranean variant studied (94.1%). Conclusions: Three polymorphic variants namely: the Mediterranean, Chatham and A-, constituted more than 80% of G6PD deficient variants among males in Baghdad. Iraq. This observation is to some extent comparable to othe

    Revisiting the Relationship Between Fault Detection,Test Adequacy Criteria, and Test Set Size

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    The research community has long recognized a complex interrelationship between test set size, test adequacy criteria, and test effectiveness in terms of fault detection. However, there is substantial confusion about the role and importance of controlling for test set size when assessing and comparing test adequacy criteria. This paper makes the following contributions: (1) A review of contradictory analyses of the relationship between fault detection, test suite size, and test adequacy criteria. Specifically, this paper addresses the supposed contradiction of prior work and explains why test suite size is neither a confounding variable, as previously suggested,nor an independent variable that should be experimentally manipulated. (2) An explication and discussion of the experimental design and sampling strategies of prior work, together with a discussion of conceptual and statistical problems, and specific guidelines for future work. (3) A methodology for comparing test-adequacy criteria on an equal basis, which accounts for test suite size by treating it as a covariate. (4) An empirical evaluation that compares the effectiveness of coverage-based and mutation-based testing to one another and random testing. Additionally, this paper proposes probabilistic coupling, a methodology for approximating the representativeness of a set of test goals for a given set of real fault

    Practical Final Pit Depth Considering the Future Underground Mining- A case study

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    It is considered that the most economical method for the exploitation of Gol-e-Gohar Area 3 iron ore mine is to combine open-pit and underground methods. In this regard, the most critical problem is the determination of optimal final pit depth. In this paper, a method which was recently introduced on the basis of economical block models of open-pit and underground is used to determine optimal final open-pit depth of Gol-e-Gohar Area 3 mine with due regards to the future underground mining option. Considering a low cost and productive underground method as a feasible alternative for extraction of the lower part of this deposit, room and pillar was selected. It is concluded that after the assessment and comparison of different values for depth, optimal final open-pit depth was determined to be equal to 285 m

    Praktyczne zastosowania technik podejmowania decyzji do wyboru odpowiednich technologii eksploatacji w Iranie

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    Mining method selection for an explored ore-body is the critical and problematic issues in mining engineering. Selection of an unsuitable method with regards to deposit characteristics may make exploitation of the ore-body troublesome and sometimes impossible or less economic. In the past, selection of extraction method was based primarily on operating experience at similar type mine and on methods already in use in the districts of the deposit. Recently application of decision theory has been paid attention for different selection problems. Decision-making methods are not using customarily in mining engineering but they are techniques can provide solutions to the problems involving conflicting and multiple criteria as mining method selection problems. This study presents of different decision making methods in complex environment of mining activities for optimal and efficient production. The focus of this article is on inspection of the suitable mining method selection and presentation of procedure, and is based on the decision theory. This paper is divided into two sections. The first section provides an overview of the mining method selection problems and decision making theory. The second section introduces an application of the Multiple Attribute Decision Making (MADM) for mining method selection accompanied by practical illustrations.Wybór metody eksploatacji dla udokumentowanego złoża rudy jest podstawowym i bardzo trudnym zagadnieniem w inżynierii górniczej. Wybór niewłaściwej technologii eksploatacji dla złoża o określonej charakterystyce może spowodować wiele kłopotów, a w rezultacie może doprowadzić do braku możliwości wybrania tego złoża lub uczynić eksploatację mniej opłacalną. W przeszłości wybór metody eksploatacji wykonywany był na podstawie doświadczeń ruchowych w kopalniach podobnego typu, a opierano się na metodach już wykorzystywanych w innych częściach tego złoża. Ostatnio zwrócono uwagę na możliwość wykorzystania metod podejmowania decyzji do rozwiązywania problemów związanych z takim wyborem. Takie metody podejmowania decyzji nie są zwykle używane w górnictwie, ale są to techniki, które mogą dać rozwiązanie w zagadnieniach, w których występuje wiele wzajemnie sprzecznych kryteriów tak jak to ma miejsce w przypadku wyboru technologii eksploatacji. Artykuł prezentuje różne metody podejmowania decyzji dla osiągnięcia optymalnej i wydajnej produkcji w złożonych uwarunkowaniach związanych z działalnością górniczą. Celem tego artykułu jest, w oparciu o teorie podejmowania decyzji, wybór odpowiedniej metody eksploatacji oraz opis tej procedury. Artykuł podzielono na dwie części. Pierwsza część daje przegląd problemów związanych z wyborem metody eksploatacji oraz teorię podejmowania decyzji. Druga część omawia wielokryterialną analizę decyzyjną zastosowaną do wyboru metody eksploatacji wraz z przykładami
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