166 research outputs found

    Kajian Alat Tangkap Mini Trawl Nelayan Pulau Tinggi Desa Penutuk Kecamatan Lepar Pongok Kabupaten Bangka Selatan

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    Mini trawls are included in the classification of trawls with using the method of operation by means of being pulled by a moving ship chasing a group of fish. This research was conducted in February 2019 to March 2019 at Pulau Tinggi of Lepar Pongok South Bangka. The purpose of this research is to know fishing ground distribution of catching fish, indetification of fishing tools of mini trawl, identification the result of  fishing catch and aspects of fishermen economic conditions of mini trawl. The method was used  interview survey. The analysis was carried out by descriptive analysis. The result show that the location of fishing ground is 2 location that are Karang Pelawang waters and Pasir Putih Waters.  The Identification of fishing tools of mini trawls there are wing of nets, belly, otter board, cod end, head rope, ground rope, warp rope, float and sinker. There are 8 spesies fish caught, the local name are Jerebung shrimp (Fenneropeanus merguienis), Selar fish (Selar crumenophtahalmus), Kurisi fish (Nemipterus furcosus), Pepetek (Leiognathus equulus), Cermin fish (Alectis indica), kuda laut (Hippocampus cuvier) dan Buntal fish(Legochepalus fugu).Mini Trawl masuk dalam klasifikasi pukat hela dimana cara pengoperasiannya dengan cara ditarik oleh kapal yang bergerak mengejar gerombolan ikan. Penelitian ini dilaksanakan pada bulan  Februari- Maret 2019 di Pulau Tinggi Desa Penutuk Kecamatan Lepar Pongok Kabupaten Bangka Selatan. Penelitian ini bertujuan untuk mengetahui wilayah penangkapan ikan oleh nelayan mini trawl, mengidentifikasi alat tangkap, mengidentifikasi hasil tangkapan dan aspek kondisi ekonomi nelayan mini trawl yang ada di Pulau Tinggi Kabupaten Bangka Selatan. Metode penelitian ini menggunakan metode deskriptif dengan jenis metode survei meliputi aspek kontruksi alat tangkap, wilayah penangkapan dan hasil tangkapan. Hasil Penelitian menunjukan bahwa daerah penangkapan ikan mini trawl berada pada dua perairan yaitu Perairan Karang Pelawang dan Perairan Pasir Putih. Identifikasi kontruksi alat tangkap mini trawl adalah sayap jaring, badan jaring, kantong jaring, papan rentan, tali ris atas dan bawah, tali selambar, pemberat dan pelampung. Identifikasi hasil tangkapan didapatkan 8 jenis spesies yang tertangkap yaitu udang jerebung (Fenneropeanus merguienis), selar(Selar crumenophtahalmus), kurisi (Nemipterus furcosus), pepetek (Leiognathus equulus), ikan cermin (Alectis indica), kuda laut (Hippocampus cuvier) dan buntal(Legochepalus fugu)

    Transdermal microconduits by microscission for drug delivery and sample acquisition

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    BACKGROUND: Painless, rapid, controlled, minimally invasive molecular transport across human skin for drug delivery and analyte acquisition is of widespread interest. Creation of microconduits through the stratum corneum and epidermis is achieved by stochastic scissioning events localized to typically 250 μm diameter areas of human skin in vivo. METHODS: Microscissioning is achieved by a limited flux of accelerated gas: 25 μm inert particles passing through the aperture in a mask held against the stratum corneum. The particles scize (cut) tissue, which is removed by the gas flow with the sensation of a gentle stream of air against the skin. The resulting microconduit is fully open and may be between 50 and 200 μm deep. RESULTS: In vivo adult human tests show that microconduits reduce the electrical impedance between two ECG electrodes from approximately 4,000 Ω to 500 Ω. Drug delivery has been demonstrated in vivo by applying lidocaine to a microconduit from a cotton swab. Sharp point probing demonstrated full anaesthesia around the site within three minutes. Topical application without the microconduit required approximately 1.5 hours. Approximately 180 μm deep microconduits in vivo yielded blood sample volumes of several μl, with a faint pricking sensation as blood enters tissue. Blood glucose measurements were taken with two commercial monitoring systems. Microconduits are invisible to the unaided eye, developing a slight erythematous macule that disappears over days. CONCLUSION: Microscissioned microconduits may provide a minimally invasive basis for delivery of any size molecule, and for extraction of interstitial fluid and blood samples. Such microconduits reduce through-skin electrical impedance, have controllable diameter and depth, are fully open and, after healing, no foreign bodies were visible using through-skin confocal microscopy. In subjects to date, microscissioning is painless and rapid

    Towards Protein Crystallization as a Process Step in Downstream Processing of Therapeutic Antibodies: Screening and Optimization at Microbatch Scale

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    Crystallization conditions of an intact monoclonal IgG4 (immunoglobulin G, subclass 4) antibody were established in vapor diffusion mode by sparse matrix screening and subsequent optimization. The procedure was transferred to microbatch conditions and a phase diagram was built showing surprisingly low solubility of the antibody at equilibrium. With up-scaling to process scale in mind, purification efficiency of the crystallization step was investigated. Added model protein contaminants were excluded from the crystals to more than 95%. No measurable loss of Fc-binding activity was observed in the crystallized and redissolved antibody. Conditions could be adapted to crystallize the antibody directly from concentrated and diafiltrated cell culture supernatant, showing purification efficiency similar to that of Protein A chromatography. We conclude that crystallization has the potential to be included in downstream processing as a low-cost purification or formulation step

    Influence of liquid structure on diffusive isotope separation in molten silicates and aqueous solutions

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    Molecular diffusion in natural volcanic liquids discriminates between isotopes of major ions (e.g., Fe, Mg, Ca, and Li). Although isotope separation by diffusion is expected on theoretical grounds, the dependence on mass is highly variable for different elements and in different media. Silicate liquid diffusion experiments using simple liquid compositions were carried out to further probe the compositional dependence of diffusive isotopic discrimination and its relationship to liquid structure. Two diffusion couples consisting of the mineral constituents anorthite (CaAl{sub 2}Si{sub 2}O{sub 8}; denoted AN), albite (NaAlSi{sub 3}O{sub 8}; denoted AB), and diopside (CaMgSi{sub 2}O{sub 6}; denoted DI) were held at 1450°C for 2 h and then quenched to ambient pressure and temperature. Major-element as well as Ca and Mg isotope profiles were measured on the recovered quenched glasses. In both experiments, Ca diffuses rapidly with respect to Si. In the AB–AN experiment, D{sub Ca}/D{sub Si} ~ 20 and the efficiency of isotope separation for Ca is much greater than in natural liquid experiments where D{sub Ca}/D{sub Si} ~ 1. In the AB–DI experiment, D{sub Ca}/D{sub Si} ~ 6 and the efficiency of isotope separation is between that of the natural liquid experiments and the AB–AN experiment. In the AB–DI experiment, D{sub Mg}/D{sub Si} ~ 1 and the efficiency of isotope separation for Mg is smaller than it is for Ca yet similar to that observed for Mg in natural liquids. The results from the experiments reported here, in combination with results from natural volcanic liquids, show clearly that the efficiency of diffusive separation of Ca isotopes is systematically related to the solvent-normalized diffusivity—the ratio of the diffusivity of the cation (D{sub Ca}) to the diffusivity of silicon (D{sub Si}). The results on Ca isotopes are consistent with available data on Fe, Li, and Mg isotopes in silicate liquids, when considered in terms of the parameter D{sub cation}/D{sub Si}. Cations diffusing in aqueous solutions display a similar relationship between isotopic separation efficiency and D{sub cation} =D{sub H 2 O} , although the efficiencies are smaller than in silicate liquids. Our empirical relationship provides a tool for predicting the magnitude of diffusive isotopic effects in many geologic environments and a basis for a more comprehensive theory of isotope separation in liquid solutions. We present a conceptual model for the relationship between diffusivity and liquid structure that is consistent with available data

    Alpha-2-Macroglobulin Is Acutely Sensitive to Freezing and Lyophilization: Implications for Structural and Functional Studies.

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    Alpha-2-macroglobulin is an abundant secreted protein that is of particular interest because of its diverse ligand binding profile and multifunctional nature, which includes roles as a protease inhibitor and as a molecular chaperone. The activities of alpha-2-macroglobulin are typically dependent on whether its conformation is native or transformed (i.e. adopts a more compact conformation after interactions with proteases or small nucleophiles), and are also influenced by dissociation of the native alpha-2-macroglobulin tetramer into stable dimers. Alpha-2-macroglobulin is predominately present as the native tetramer in vivo; once purified from human blood plasma, however, alpha-2-macroglobulin can undergo a number of conformational changes during storage, including transformation, aggregation or dissociation. We demonstrate that, particularly in the presence of sodium chloride or amine containing compounds, freezing and/or lyophilization of alpha-2-macroglobulin induces conformational changes with functional consequences. These conformational changes in alpha-2-macroglobulin are not always detected by standard native polyacrylamide gel electrophoresis, but can be measured using bisANS fluorescence assays. Increased surface hydrophobicity of alpha-2-macroglobulin, as assessed by bisANS fluorescence measurements, is accompanied by (i) reduced trypsin binding activity, (ii) increased chaperone activity, and (iii) increased binding to the surfaces of SH-SY5Y neurons, in part, via lipoprotein receptors. We show that sucrose (but not glycine) effectively protects native alpha-2-macroglobulin from denaturation during freezing and/or lyophilization, thereby providing a reproducible method for the handling and long-term storage of this protein.Early Career Fellowship from the National Health and Medical Research Council GNT1012521(A.R.W.); Wellcome Trust Programme Grant (J.R.K., C.M.D.) 094425/Z/10/Z; Samsung GRO Grant (M.R.W.)This is the final version of the article. It first appeared from PLoS via http://dx.doi.org/10.1371/journal.pone.013003
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