313 research outputs found
Seasonal variation of chemical composition and fatty acid profile of ovary in wild common carp (Cyprinus carpio) of southeastern Caspian Sea
Chemical composition and fatty acid profile of common carp's gonad (ovary) were assessed. Protein, lipid, fatty acid profile and moisture content were determined during 4 seasons’ summer, autumn, winter in 2007 and spring in 2008. For each season 10 samples were examined. Average of gonadosomatic index in wild common carp was 7.53 ±5.02. Proximate composition of ovary during the study period showed the lipid at 8.06 ±2.20; protein at 23.26 ±4.85; and moisture at 67.12 ±3.85. The results showed lipid content of wild fish ovary increased from summer to spring (summer 6.875 ±0.53; autumn 7.07 ±2.12; winter 7.96 ±1.22; spring 9.44 ±3.62), protein content also increased from summer to spring (summer 12.920.09; autumn 23 ±1.32; winter 25.16 ±0.63; spring 27.11 ±0.63), moisture content decreased in this period (summer 75.235 ±1.75; autumn 68.25 ±2.28; winter 65.685 ±0.40; spring 63.43 ±0.11). Significant differences (P0.05). Saturated and polyunsaturated fatty acids increased from summer to spring (spawning season). The major fatty acids identified in common carp ovary were Oleic (C18:1), palmitic (C16:0), Docosahexanoic acid (C22:6 DHA), Palmitoleic (C16:1), Arachidonic, AA (C20:4), Stearic (C18:0), Eicosapentaenoic acid (C20:5 EPA) and Linoleic (C18:2) in all seasons. Lipid, protein and omega 3 PUFA increased during gonad maturation. It seems that these resources of energy are necessary for embryogenesis
Effect of extrinsic and intrinsic parameters on inulinase production by Aspergillus niger ATCC 20611
Background: Inulinase is a versatile enzyme from glycoside hydrolase
family which targets the \u3b2-2, 1 linkage of fructopolymers. In the
present study, the effect of medium composition and culture conditions
on inulinase production by Aspergillus niger ATCC 20611 was
investigated in shake-flasks. Results: The highest extracellular
inulinase (3199 U/ ml) was obtained in the presence of 25% (w/v)
sucrose, 0.5% (w/v) meat extract, 1.5% (w/v) NaNO3 and 2.5 mM (v/v)
Zn2+, at initial pH of 6.5, temperature 35\ubaC and 6% (v/v) of
spores suspension in the agitation speed of 100 rpm. Surfactants showed
an inhibitory effect on enzyme production. The optimum temperature for
inulinase activity was found to be 50\ubaC. TLC analysis showed the
presence of both exo- and endo-inulinase. Conclusion: Sucrose, Zn2+,
and aeration were found to be the most effective elements in inulinase
production by A. niger ATCC 20611. TLC analysis also showed that the
crude enzyme contained both endo and exoinulinases. The strain is
suggested as a potential candidate for industrial enzymatic production
of fructose from inulin
Observation of a charged charmoniumlike structure in at GeV
We study the process at a
center-of-mass energy of 4.26GeV using a 827pb data sample obtained with
the BESIII detector at the Beijing Electron Positron Collider. Based on a
partial reconstruction technique, the Born cross section is measured to be
pb. We observe a structure near the
threshold in the recoil mass spectrum, which we denote as the
. The measured mass and width of the structure are
MeV/c and MeV, respectively. Its
production ratio is determined to be . The first uncertainties
are statistical and the second are systematic.Comment: 7 pages, 4 figures, 1 table; version accepted to be published in PR
Search for C-parity violation in and
Using events recorded in
collisions at 3.686 GeV with the BESIII at the BEPCII collider, we
present searches for C-parity violation in and decays via . No significant
signals are observed in either channel. Upper limits on the branching fractions
are set to be and
at the 90\%
confidence level. The former is one order of magnitude more stringent than the
previous upper limit, and the latter represents the first limit on this decay
channel.Comment: 7 pages, 2 figure
Search for the Lepton Flavor Violation Process at BESIII
We search for the lepton-flavor-violating decay of the into an
electron and a muon using events
collected with the BESIII detector at the BEPCII collider. Four candidate
events are found in the signal region, consistent with background expectations.
An upper limit on the branching fraction of (90% C.L.) is obtained
Search for Baryonic Decays of \psi(3770) and \psi(4040)
By analyzing data samples of 2.9 fb^{-1} collected at \sqrt s=3.773 GeV, 482
pb^{-1} collected at \sqrt s=4.009 GeV and 67 pb^{-1} collected at \sqrt
s=3.542, 3.554, 3.561, 3.600 and 3.650 GeV with the BESIII detector at the
BEPCII storage ring, we search for \psi(3770) and \psi(4040) decay to baryonic
final states, including \Lambda\bar\Lambda\pi^+\pi^-, \Lambda \bar\Lambda\pi^0,
\Lambda\bar\Lambda\eta, \Sigma^+ \bar\Sigma^-, \Sigma^0 \bar\Sigma^0,
\Xi^-\bar\Xi^+ and \Xi^0\bar\Xi^0 decays. None are observed, and upper limits
are set at the 90% confidence level.Comment: 9 pages, 3 figure
Observation of at BESIII
Using events collected with the BESIII detector
at the BEPCII storage rings, we observe for the first time the process
,
with a significance of ( including systematic
uncertainties). The product branching fraction of is measured to be
, where the first error is statistical and the
second is systematic. This measurement provides information on the
production near threshold coupling to and improves the understanding
of the dynamics of decays to four body processes.Comment: 8 pages, 7 figure
Precision Measurement of the Mass of the Lepton
An energy scan near the pair production threshold has been performed
using the BESIII detector. About pb of data, distributed over four
scan points, was collected. This analysis is based on pair decays to
, , , , , , , and
final states, where denotes a charged or . The mass of the
lepton is measured from a maximum likelihood fit to the pair production
cross section data to be )
MeV/, which is currently the most precise value in a single measurement.Comment: 13 pages, 7 figure
Search for the radiative transitions and
By using a 2.92 fb data sample taken at GeV with
the BESIII detector operating at the BEPCII collider, we search for the
radiative transitions and
through the hadronic decays . No
significant excess of signal events above background is observed. We set upper
limits at a 90% confidence level for the product branching fractions to be
and
. Combining our result with world-average
values of , we find the
branching fractions
and at a 90%
confidence level.Comment: 10 pages, 4 figure
Observation of and a neutral charmoniumlike structure
Using data collected with the BESIII detector operating at the Beijing
Electron Positron Collider at center-of-mass energies of , 4.26,
and 4.36~GeV, we observe \EE\to \pphc for the first time. The Born cross
sections are measured and found to be about half of those of \EE\to
\pi^+\pi^-h_c within less than 2. In the mass spectrum, a
structure at 4.02~GeV/ is found. It is most likely to be the neutral
isospin partner of the \zcp^{\pm} observed in the process of \EE\to
\pi^+\pi^-h_c is found. A fit to the invariant mass spectrum, with
the width of the \zcpn fixed to that of its charged isospin partner and
possible interferences with non-\zcpn amplitudes neglected, gives a mass of
()~MeV/ for the \zcpn, where the first error is
statistical and the second systematic.Comment: 7 pages, 2 figure
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