3,136 research outputs found

    ANALISIS FAKTOR-FAKTOR YANG MEMPENGARUHI PRODUKSI IKAN BANDENG DI KOTA BANDA ACEH

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    ABSTRAKPenelitian ini bertujuan untuk mengetahui faktor-faktor yang mempengaruhi produksi ikan bandeng di Kota Banda Aceh. Penelitian ini dilakukan menggunakan metode survey dan pengambilan sampelnya dengan teknik sampel acak sederhana Simple Random Sampling.Lokasi penelitian dilakukan di Kota Banda Aceh, yaitu Kecamatan Syiah Kuala, Meuraxa, Kuta Alam, dan Kuta Raja. Waktu Penelitian dilaksanakan pada bulan Oktober 2013 sampai dengan Juli 2014. Model yang digunakan dalam penelitian ini adalah menggunakan model analisis kuantitatif untuk mengetahui Faktor-faktor yang mempengaruhi produksi ikan bandeng di Kota Banda Aceh yaitu tenaga kerja, luas tambak, jumlah nener, dan penggunaan pupuk..Untuk menguji hubungan antara variabel faktor-faktor yang mempengaruhi produksi ikan bandeng di Kota Banda Aceh, digunakan uji statistik dengan menggunakan uji T, F, dan R2.Hasil penelitian ini dapat disimpulkan bahwa secara serempak faktor , tenaga kerja, luas tambak, jumlah nener, dan jumlah pupuk berpengaruh nyata terhadap produksi ikan bandeng di Kota Banda Aceh. Secara parsial faktor jumlah nener berpengaruh nyata terhadap produksi ikan bandeng di Kota Banda Aceh. Sedangkan faktor tenaga kerja, luas tambak dan jumlah pupuk tidak berpengaruh nyata terhadap produksi ikan bandeng di Kota Banda Aceh.Kata Kunci: Ikan bandeng, analisis produksiABSTRACTThis research aims to determine the factors that affect fish production in the city of Banda Aceh. This research was conducted using a survey method and sampling with simple random sampling techniques.Location of the research conducted in the city of Banda Aceh , the District Syiah KuaLa, Meuraxa, Kuta Alam, and Kuta Raja. Time research conducted in October 2013 to July 2014 model used in this research was to use quantitative analysis model to determine the factors that affect milkfish production in Banda Aceh, namely labor, large farms, the amount of milkfish, and use of fertilizers.For Examine the relationship between the variable factors that affect milkfish production in Banda Aceh, used statistical tests using T test, F, and R2.The results of this research it can be concluded that the factors simultaneously, labor, large ponds, milkfish amount, and the amount of fertilizer significantly affect milkfish production in the city of Banda Aceh. Partially factors significantly affect the amount of milkfish fry production of milkfish in Banda Aceh. While the labor factor, vast farms and the amount of fertilizer had no significant effect on the production of milkfish in Banda Aceh .Keywords: Milkfish, production analysisBanda Ace

    Variable parameters for a single exponential model of photovoltaic modules in crystalline-silicon

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    The correct approximation of parallel resistance (Rp) and series resistance (Rs) poses a major challenge for the single diode model of the photovoltaic module (PV). The bottleneck behind the limited accuracy of the model is the static estimation of resistive parameters. This means that Rp and Rs, once estimated, usually remain constant for the entire operating range of the same weather condition, as well as for other conditions. Another contributing factor is the availability of only standard test condition (STC) data in the manufacturer’s datasheet. This paper proposes a single-diode model with dynamic relations of Rp and Rs. The relations not only vary the resistive parameters for constant/distinct weather conditions but also provide a non-iterative solution. Initially, appropriate software is used to extract the data of current-voltage (I-V) curves from the manufacturer’s datasheet. By using these raw data and simple statistical concepts, the relations for Rp and Rs are designed. Finally, it is proved through root mean square error (RMSE) analysis that the proposed model holds a one-tenth advantage over numerous recently proposed models. Simultaneously, it is low complex, iteration-free (0 to voltage in maximum power point Vmpp range), and requires less computation time to trace the I-V curve

    Lesson learned from the recovery of an orphan source inside a maritime cargo: analysis of the nuclear instrumentations used, and measures realized during the operations

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    In this paper, the authors analyze the case study of the recovery of an orphan source of 60Co inside a maritime cargo full of metal wastes in the Italian Harbor of Genova carried out by the Italian Fire Fighters. Orphan radioactive sources or Radiological Dispersal Devices are a critical security issue in large geographical areas, and they result in a safety concern for people who may become accidentally exposed to ionizing radiation. The abandonment of orphan sources can usually be related to three factors: human errors, cost reasons (in order to avoid the payment of disposal procedures), or malevolent purposes (like the production of dirty bombs). The present data concern the nuclear safety measures implemented during the recovery event and the pool of procedures carried out in order to reduce the risks for the involved harbor operators. Following data collection and analysis, an important lesson about the management of such events and scenarios can be learned

    MOLECULAR CHARACTERISATION OF A NOVEL ADP-RIBOSYLATING PUTATIVE TOXIN OF NEISSERIA MENINGITIDIS

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    Molecular characterisation of a novel ADP-ribosylating putative toxin of Neisseria meningitidis VEGGIi D, *BALDUCCI E, MASIGNANI V, DI MARCELLO F, SAVINO S, ARICO’ B, COMANDUCCI M, PIZZA M, RAPPUOLI R IRIS, Chiron SpA, Via Fiorentina 1, 53100 Siena Italy; *Dipartimento Scienze morfologiche e Biochimiche Comparate, Università degli Studi di Camerino, Camerino, Italy Session: Surface antigens Introduction: By computer analysis on the Neisseria meningitidis (serogroup B, MC 58 strain) genome sequence, a protein with a feature similar to known bacterial ADP-ribosylating toxins (CT produced by Vibrio cholerae, LT by Escherichia coli and PT by Bordetella pertussis) has been identified. Enzymatic assay has shown that this protein (NM-ADPRT) possesses both NAD glycohydrolase and ADP-ribosyltransferase activity. In this study we describe the identification of the putative catalytic residues, their site-directed mutagenesis, and the resulting activity of the mutants. Materials and methods: The novel NM-ADPRT and the correspondent mutants, were expressed in E. coli as C-terminus His-tag protein fusions. Site-directed mutagenesis was performed using the Multi Site-Directed Mutagenesis Kit (QuikChange). Recombinant NM-ADPRT forms were purified from E. coli in their soluble form by metal chelate affinity chromatography. Both the wild-type and the mutants were assayed for their ADP-ribosylation and NAD-glycohydolase activites, using [adenine –U-14C] NAD and agmatine as ADP-ribose acceptor. Antisera against NM-ADPRT and the mutant derivatives were obtained by immunization of CD1 mice. 20μg of each recombinant protein were given i.p. together with CFA for the first dose and IFA for the second (day 21) and the third (day 35) booster doses. Blood sample were taken on days 34 and 49. Immune sera were used in western blot and tested in a bactericidal assay. Results and discussion: On the basis of sequence homology of NM-ADPRT with LT, CT and PT we have identified the putative residues involved in enzymatic activity. These residues have been changed by site-directed mutagenesis and the purified mutant toxins have been tested for both ADP-ribosylating and NAD-glycohydrolase activities. Interestingly, some of the mutants show reduced or abolished enzymatic activity indicating that the identified residues play a role in catalysis. Antisera against the wild-type and mutant toxins have bactericidal activity. The titers induced by two mutants were higher than those induced by the wild-type form. These data suggest that the mutations introduced could influence not only the enzymatic activity but also the in vivo stability of the toxin. Conclusion: A novel ADP-ribosyltransferase has been identified in meningococcus B. Catalytic residues have been predicted by sequence homology and their role in catalysis has been confirmed by site-directed mutagenesis. These molecules are also able to induce a bactericidal response

    Spectrometer for X-ray emission experiments at FERMI free-electron-laser

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    A portable and compact photon spectrometer to be used for photon in-photon out experiments, in particular x-ray emission spectroscopy, is presented. The instrument operates in the 25\u2013800 eV energy range to cover the full emissions of the FEL1 and FEL2 stages of FERMI. The optical design consists of two interchangeable spherical varied-lined-spaced gratings and a CCD detector. Different input sections can be accommodated, with/without an entrance slit and with/without an additional relay mirror, that allow to mount the spectrometer in different end-stations and at variable distances from the target area both at synchrotron and at free-electron-laser beamlines. The characterization on the Gas Phase beamline at ELETTRA Synchrotron (Italy) is presented

    Structural and biochemical characterization of NarE, an iron-containing ADP-ribosyltransferase from Neisseria meningitidis.

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    Abstract NarE is a 16 kDa protein identified from Neisseria meningitidis, one of the bacterial pathogens responsible for meningitis. NarE belongs to the family of ADP-ribosyltransferases (ADPRT) and catalyzes the transfer of ADP-ribose moieties to arginine residues in target protein acceptors. Many pathogenic bacteria utilize ADP-ribosylating toxins to modify and alter essential functions of eukaryotic cells. NarE is further the first ADPRT which could be shown to bind iron through a Fe-S center, which is crucial for the catalytic activity. Here we present the NMR solution structure of NarE, which shows structural homology to other ADPRTs. Using NMR titration experiments we could identify from Chemical Shift Perturbation data both the NAD binding site, which is in perfect agreement with a consensus sequence analysis between different ADPRTs, as well as the iron coordination site, which consists of 2 cysteines and 2 histidines. This atypical iron coordination is also capable to bind zinc. These results could be fortified by site-directed mutagenesis of the catalytic region, which identified two functionally crucial residues. We could further identify a main interaction region of NarE with antibodies using two complementary methods based on antibody immobilization, proteolytic digestion, and mass spectrometry. This study combines structural and functional features of NarE providing for the first time a characterization of an iron-dependent ADPRT
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