539 research outputs found
Karakteristik Organoleptik Filet Ikan Patin (Pangasionodon Hypophthalmus) dari Tiga Lokasi Budidaya di Kabupaten Bogor
Hasil olahan ikan Patin (Pangasionodon hypophthalmus) pada umumnya dipasarkan dalam bentuk fillet, baik beku maupun berbalut tepung roti. Kualitas organoleptik fillet patin ini sangat dipengaruhi oleh berbagai faktor, diantaranya kualitas lingkungan perairan tempat budidaya ikan tersebut, baik fisika maupun kimia. Penelitian ini bertujuan untuk mengidentifikasi karakteristik organoleptik filet ikan patin secara sensori, yang diperoleh dari tiga lokasi budidaya dengan kualitas air yang berbeda di Kabupaten Bogor. Penelitian berlangsung mulai bulan Maret sampai dengan Juni 2013 bertempat di Desa Bantar Kemang, Desa Ciseeng, serta kolam praktek Pasir Jaya Jurusan Penyuluhan Perikanan. Parameter yang diamati terhadap fillet patin meliputi aroma, rasa, penampakan, serta tekstur. Adapun untuk parameter kualtas air terdiri dari suhu, pH, kecerahan, oksigen terlarut, nitrit, amoniak, serta amonium. Hasil penelitian menunjukkan bahwa nilai karakteristik organoleptik illet ikan patin untuk atribut aroma dan rasa dipengaruhi oleh kualitas air
Pertanggungjawaban Perusahaan Induk terhadap Perusahaan Anak dalam Hal Terjadinya Pencemaran Dan/atau Kerusakan Lingkungan Hidup
Group corporation as one of the effects of the fast growing economy, in the activities can also play a role in terms of pollution and/or environmental damage done by one or several subsidiaries. In this regard, the parent corporation may be subject to liability in certain cases where there is contamination and/or damage to the environment done by the subsidiary. Based on the results of research, it can be seen that the legal relationship between the parent corporation to the subsidiaries is the employment relationship or other relationship within the scope of work of the enterprise. The parent corporation may be subject to civil liability for pollution and/or environmental damage done by the subsidiary if the parent corporation controls the subsidiaries proven to perform actions within the scope of application of piercing the corporate veil. In addition, the parent corporation may also incur criminal liability if it is proved the parent corporation were also committing a crime of pollution and/or environmental damage done by the subsidiary. Based on this research, it is advisable to make a special provision of group companies in Limited Company Act. In addition, it should be prioritizing the use of criminal law in a law enforcement environment that affects the survival of human beings, as well as the need to increase the moral of businessmen for committing violations of environmental laws
Soluble expression, purification and characterization of the full length IS2 Transposase
<p>Abstract</p> <p>Background</p> <p>The two-step transposition pathway of insertion sequences of the IS<it>3 </it>family, and several other families, involves first the formation of a branched figure-of-eight (F-8) structure by an asymmetric single strand cleavage at one optional donor end and joining to the flanking host DNA near the target end. Its conversion to a double stranded minicircle precedes the second insertional step, where both ends function as donors. In IS<it>2</it>, the left end which lacks donor function in Step I acquires it in Step II. The assembly of two intrinsically different protein-DNA complexes in these F-8 generating elements has been intuitively proposed, but a barrier to testing this hypothesis has been the difficulty of isolating a full length, soluble and active transposase that creates fully formed synaptic complexes <it>in vitro </it>with protein bound to both binding and catalytic domains of the ends. We address here a solution to expressing, purifying and structurally analyzing such a protein.</p> <p>Results</p> <p>A soluble and active IS<it>2 </it>transposase derivative with GFP fused to its C-terminus functions as efficiently as the native protein in <it>in vivo </it>transposition assays. <it>In vitro </it>electrophoretic mobility shift assay data show that the partially purified protein prepared under native conditions binds very efficiently to cognate DNA, utilizing both N- and C-terminal residues. As a precursor to biophysical analyses of these complexes, a fluorescence-based random mutagenesis protocol was developed that enabled a structure-function analysis of the protein with good resolution at the secondary structure level. The results extend previous structure-function work on IS<it>3 </it>family transposases, identifying the binding domain as a three helix H + HTH bundle and explaining the function of an atypical leucine zipper-like motif in IS<it>2</it>. In addition gain- and loss-of-function mutations in the catalytic active site define its role in regional and global binding and identify functional signatures that are common to the three dimensional catalytic core motif of the retroviral integrase superfamily.</p> <p>Conclusions</p> <p>Intractably insoluble transposases, such as the IS<it>2 </it>transposase, prepared by solubilization protocols are often refractory to whole protein structure-function studies. The results described here have validated the use of GFP-tagging and fluorescence-based random mutagenesis in overcoming this limitation at the secondary structure level.</p
Radiation reaction and the self-force for a point mass in general relativity
A point particle of mass m moving on a geodesic creates a perturbation h, of
the spacetime metric g, that diverges at the particle. Simple expressions are
given for the singular m/r part of h and its quadrupole distortion caused by
the spacetime. Subtracting these from h leaves a remainder h^R that is C^1. The
self-force on the particle from its own gravitational field corrects the
worldline at O(m) to be a geodesic of g+h^R. For the case that the particle is
a small non-rotating black hole, an approximate solution to the Einstein
equations is given with error of O(m^2) as m approaches 0.Comment: 4 pages, RevTe
Are Post-Newtonian templates faithful and effectual in detecting gravitational signals from neutron star binaries?
We compute the overlap function between Post-Newtonian (PN) templates and
gravitational signals emitted by binary systems composed of one neutron star
and one point mass, obtained by a perturbative approach. The calculations are
performed for different stellar models and for different detectors, to estimate
how effectual and faithful the PN templates are, and to establish whether
effects related to the internal structure of neutron stars may possibly be
extracted by the matched filtering technique.Comment: 14 pages, 3 figures, accepted for publication in Phys. Rev.
Retarded coordinates based at a world line, and the motion of a small black hole in an external universe
In the first part of this article I present a system of retarded coordinates
based at an arbitrary world line of an arbitrary curved spacetime. The
retarded-time coordinate labels forward light cones that are centered on the
world line, the radial coordinate is an affine parameter on the null generators
of these light cones, and the angular coordinates are constant on each of these
generators. The spacetime metric in the retarded coordinates is displayed as an
expansion in powers of the radial coordinate and expressed in terms of the
world line's acceleration vector and the spacetime's Riemann tensor evaluated
at the world line. The formalism is illustrated in two examples, the first
involving a comoving world line of a spatially-flat cosmology, the other
featuring an observer in circular motion in the Schwarzschild spacetime. The
main application of the formalism is presented in the second part of the
article, in which I consider the motion of a small black hole in an empty
external universe. I use the retarded coordinates to construct the metric of
the small black hole perturbed by the tidal field of the external universe, and
the metric of the external universe perturbed by the presence of the black
hole. Matching these metrics produces the MiSaTaQuWa equations of motion for
the small black hole.Comment: 20 pages, revtex4, 2 figure
An approximate binary-black-hole metric
An approximate solution to Einstein's equations representing two
widely-separated non-rotating black holes in a circular orbit is constructed by
matching a post-Newtonian metric to two perturbed Schwarzschild metrics. The
spacetime metric is presented in a single coordinate system valid up to the
apparent horizons of the black holes. This metric could be useful in numerical
simulations of binary black holes. Initial data extracted from this metric have
the advantages of being linked to the early inspiral phase of the binary
system, and of not containing spurious gravitational waves.Comment: 20 pages, 1 figure; some changes in Sec. IV B,C and Sec.
Time-symmetric initial data for binary black holes in numerical relativity
We look for physically realistic initial data in numerical relativity which
are in agreement with post-Newtonian approximations. We propose a particular
solution of the time-symmetric constraint equation, appropriate to two
momentarily static black holes, in the form of a conformal decomposition of the
spatial metric. This solution is isometric to the post-Newtonian metric up to
the 2PN order. It represents a non-linear deformation of the solution of Brill
and Lindquist, i.e. an asymptotically flat region is connected to two
asymptotically flat (in a certain weak sense) sheets, that are the images of
the two singularities through appropriate inversion transformations. The total
ADM mass M as well as the individual masses m_1 and m_2 (when they exist) are
computed by surface integrals performed at infinity. Using second order
perturbation theory on the Brill-Lindquist background, we prove that the
binary's interacting mass-energy M-m_1-m_2 is well-defined at the 2PN order and
in agreement with the known post-Newtonian result.Comment: 27 pages, to appear in Phys. Rev.
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