92 research outputs found

    Effect of mixed and artificial feeding on the growth performance of Gattan Luciobarbus xanthopterus Heckel, 1843 larvae

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    This work aimed to study the rearing feasibility of Luciobarbus xanthopterus larvae using artificial and mixed (live (Chlorella sp.) + artificial) food and their effects on their growth performance during early development. Larvae (1.65 cm in length and 0.02 g weight) were obtained from a Marine Science Hatchery and cultured in indoor tanks for 35 days. the larvae fed mixed feed T1 and artificial feed T2 (fish meal + soybean meal). The results showed that the larvae of T1 treatment outperformed significantly in final length, final weight, final weight gain, daily and specific growth rate, which amounted to 3.44 cm, 0.3568 g, 0.3368 g, 0.0096 g/day, and 8.2185 % weight/day, respectively. Also, the results showed that larvae fed on T1 grew faster. The present study showed that applying a mixture of artificial and live food after four weeks' age i.e. after absorption of the yolk sac for feeding larvae can reduce the costs of producing and providing better growth and survival rates

    Removal of Cadmium(II) Onto Granular Activated Carbon And Kaolinite Using Batch Adsorption

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    The removal of Cd(II) onto granular activated carbon (GAC) and kaolinite in singlecomponent systems has been studied using batch adsorption. Batch adsorption studied werecarried out under various amount of GAC and Kaolinite, Cd(II) ion concentration, pH andcontact time. The experimental data was analyzed by Langmuir, Freundlich and Redlich-Peterson isotherms. The equilibrium adsorption capacity of Cd(II) was determined fromLangmuir isotherm equation and found to be 3.002 mg/g for GAC and 1.837 mg/g forkaolinite. Pore diffusion model for batch adsorption is used to predict the concentrationdecaycurve for adsorption of Cd(II) onto GAC and kaolinite

    Phylotyping and Functional Analysis of Two Ancient Human Microbiomes

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    Background: The Human Microbiome Project (HMP) is one of the U.S. National Institutes of Health Roadmap for Medical Research. Primary interests of the HMP include the distinctiveness of different gut microbiomes, the factors influencing microbiome diversity, and the functional redundancies of the members of human microbiotas. In this present work, we contribute to these interests by characterizing two extinct human microbiotas. Methodology/Principal Findings: We examine two paleofecal samples originating from cave deposits in Durango Mexico and dating to approximately 1300 years ago. Contamination control is a serious issue in ancient DNA research; we use a novel approach to control contamination. After we determined that each sample originated from a different human, we generated 45 thousand shotgun DNA sequencing reads. The phylotyping and functional analysis of these reads reveals a signature consistent with the modern gut ecology. Interestingly, inter-individual variability for phenotypes but not functional pathways was observed. The two ancient samples have more similar functional profiles to each other than to a recently published profile for modern humans. This similarity could not be explained by a chance sampling of the databases. Conclusions/Significance: We conduct a phylotyping and functional analysis of ancient human microbiomes, while providing novel methods to control for DNA contamination and novel hypotheses about past microbiome biogeography. We postulate that natural selection has more of an influence on microbiome functional profiles than it does on the species represented in the microbial ecology. We propose that human microbiomes were more geographically structured during pre-Columbian times than today

    Epigenetic regulation of caloric restriction in aging

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    The molecular mechanisms of aging are the subject of much research and have facilitated potential interventions to delay aging and aging-related degenerative diseases in humans. The aging process is frequently affected by environmental factors, and caloric restriction is by far the most effective and established environmental manipulation for extending lifespan in various animal models. However, the precise mechanisms by which caloric restriction affects lifespan are still not clear. Epigenetic mechanisms have recently been recognized as major contributors to nutrition-related longevity and aging control. Two primary epigenetic codes, DNA methylation and histone modification, are believed to dynamically influence chromatin structure, resulting in expression changes of relevant genes. In this review, we assess the current advances in epigenetic regulation in response to caloric restriction and how this affects cellular senescence, aging and potential extension of a healthy lifespan in humans. Enhanced understanding of the important role of epigenetics in the control of the aging process through caloric restriction may lead to clinical advances in the prevention and therapy of human aging-associated diseases

    EFFECT OF NOTCH DIMENSION AND LOCATION ON FATIGUE LIFE AND THERMAL BEHAVIOR OF LOW CARBON STEEL (ST37-2)

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    The effect of depth and location of the notch on the v-notched specimen on fatigue life of cantilever rotating beam of low carbon steel (ST37-2) is studied, by applying fully reversed cycle load of 150 N, and mean stress of Zero. The temperature variations during fatigue life were measured by infrared camera at three points in specimens. These points are the edge point, notch point and other specified points. Numerically, the finite element model of fatigue test was obtained using the ANSYS Workbench. The ANSYS model was based on the S/N curve measured experimentally. From the results, there is a notch position that changed the fracture position from the notch position to the edge position. Also, fatigue life can be increased by putting the notch in appropriate position on the specimen. The temperature variation at different points in the specimen gave a good prediction to the fracture position before the fracture occurs. Also, from the comparison between experimental and numerical results, the two curves were similar but the ANSYS model based on the experimental S/N curve gave a good prediction for fatigue life

    Pressure and osmotically driven membrane processes: A review of the benefits and production of nano-enhanced membranes for desalination

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    This review focuses on current research attempts to develop nano-enhanced polymeric desalination membranes. The novel contribution made by this work as compared to many recent reviews on membrane enhancement is that a critical review is made of the effect that the morphological, optical and magnetic properties of the applied nanomaterials have on the efficiency of desalination membranes. The focus on nanomaterials in this review is on both applying new chemical compositions at various concentrations, and also on altering the nanomaterials' morphology and other properties to reach the optimal membrane efficiency for desalination applications. The synthesis route has a major role of tuning the physical and chemical properties of the nanomaterials, and hence, the membrane morphological parameters can be altered, all of which are summarised in this review. The review surveys different types of nanomaterials used for membrane fabrication, such as single elements, metal oxides and nanotubes. Furthermore, mixed oxide composites and polymer/nanomaterial combinations are also considered for membrane enhancement. A wide application range is investigated for modified membranes in pressure and osmotically driven membrane processes for desalination, including reverse osmosis, forward osmosis, osmotically assisted reverse osmosis and pressure assisted forward osmosis

    Fog and Rain Water Collection from Trees in the Dhofar Region in the Sultanate of Oman

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    This work had two purposes. The first was to measure and investigate the amount of fog and rain water collected by a sample of trees during the summer monsoon season in the mountains of the Dhofar region in the south of Oman. The second purpose was to assess the potential of trees with different leaf shapes, sizes and cross sectional canopy areas to collect fog and rain water in the area. In order to meet these purposes three different tree species, were selected for experimental investigation and field measurements. They included fig, lemon, and tamarind trees. The experiments were designed and implemented in the monsoon season of 2006, between the 13th of July and the 3rd of September. The daily measurements of water collection showed that the three species of tree have different water collection capacities. It was found that the fig tree collected the least water. The fog water collection of the fig tree over a period of 47 days between the 13th of July and the 3rd of September was 140.5 L/m2, or an average of 2.7 L/m2/d. The fog water collection of the lemon tree was 243.0 L/m2, or an average of 4.4 L/m2/d. In terms of potential collection of the tamarind tree, the results showed that it collected a fog water of 218.9 L/m2, or an average of 4.3 L/m2/d over the same period. The study contributes to the knowledge of how different tree species collect fog and rain water, and concludes with a set of recommendations

    Short-term assessment of heavy metals in surface waters of the Shatt Al-Arab River

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    The Shatt Al-Arab River's water quality deteriorates naturally due to salinity intrusion, and freshwater sources decrease. Seven sampling locations along the Shatt Al-Arab River in southern Iraq were used to examine the level of six heavy metals, including Cu, Cd, Ni, Co, Mn, and Fe, during Januar-December 2021. Salinity levels in the study area ranged from 1.55 upstream to 35.15 g/L downstream of the study area. The pH of surface water ranged 7.545-8.325, indicating alkaline conditions. The concentrations of six heavy metals, viz Cu, Cd, Ni, Mn, Co, and Fe in the study area were 3.741±4.219, 3.654±4.169, 7.700± 6.251, 2.551±3.898, 2.292±3.996, and 18.236±5.583 µg/L, respectively, which decreased in the order of Fe > Ni > Cu > Cd > Mn > Co. There was a considerable change in the quantity of heavy metals throughout the year, with the summer months having the highest concentration. There is a correlation between seawater intrusion and the concentration of heavy metals in the surface waters. The mean levels of the heavy metals were below the allowed values of WHO drinking water guidelines
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