Plankton Management for Fish Culture Ponds

In the culture of larval fish of various species, e.g., walleye (Stizostedion vitreum), hybrid striped bass (Morone saxatilis X M. chrysops) and sunfish (Lepomis spp.), management of the zooplankton forage base is critical to successful transition of larvae to the fingerling stage. In addition, information regarding the relative status of plankton (zooplankton and phytoplankton) communities gives insight into water quality parameters and the possible success or failure of the culture season. The dynamic characteristics of zooplankton populations have led researchers to use particular fertilization techniques and speciesspecific zooplankton inoculations in culture ponds (Colura and Matlock 1983; Geiger 1983a; Farquhar 1984; Turner 1984; Geiger et al. 1985). The intent of these management techniques was to maintain high densities of desirable zooplankton species in culture ponds until fish were harvested or able to consume commercial feeds

Pond Culture of Hybrid Striped Bass in the North Central Region

Striped bass (Morone saxatilis) have been commercially harvested for many years, however wild stocks have declined due to environmental degradation, habitat loss and overfishing. The U.S. wild fishery of striped bass was 6.8 million kg (15 million lbs.) in 1973, but declined to less than 0.2 million kg (0.5 million lbs.) in 1990. In the past few years striped bass populations have started to rebound due to restrictions on their harvest, but are unlikely to approach the 1973 levels. In response to decreased commercial catches, the striped bass and its hybrids have been commercially produced in ponds, raceways, and tanks to fulfill the established commercial markets. The 1995 aquaculture production was 4 million kg (9 million lbs.)

Spatial variability of 14C reservoir effects in Tibetan Plateau lakes

Abstract HKT-ISTP 2013 B

Altered Proliferation, Synthetic Activity, and Differentiation of Cultured Human sebocytes in the Absence of Vitamin A and Their Modulation by Synthetic Retinoids

Human sebocytes maintained in medium containing delipidized serum were studied for ultrastructural characteristics, cell proliferation, lipid synthesis, immunophenotype, and keratin expression before and after the addition of the synthetic retinoids isotretinoin and acitretin (10-8 - 10-5 M).Compared to the properties of sebocytes cultured in normal sebocyte medium (1–2 × 10-7 M vitamin A), the use of delipidized serum (undetectable amounts of vitamin A) resulted in prominent decrease of i) proliferation; ii) number of intracellular lipid droplets and synthesis of total lipids, especially triglycerides, squalene, and wax esters; and iii) labeling with monoclonal antibodies identifying progressive and late-stage sebocyte differentiation. Intercellular spaces narrowed and cell-to-cell contacts were established by abundant desmosomes. Lanosterol was induced. Keratins 14, 16, 17, and 18 were upregulated and the keratin 16: keratin 4 ratio, negatively correlating with sebocyte differentiation, increased.Addition of isotretinoin and acitretin exerted a biphasic effect. At concentrations ≤ 10-7 M, both compounds enhanced sebocyte proliferation and synthesis of total lipids, especially triglycerides and cholesterol, and decreased Ianosterol, keratin 16, and the keratin 16: keratin 4 ratio. In contrast, retinoid concentrations > 10-7 M inhibited sebocyte proliferation in a dose-dependent manner.Our findings indicate that vitamin A is essential for proliferation, synthetic activity, and differentiation of human sebocytes in vitro. Synthetic retinoids partially reinstate the altered functions of sebocytes maintained in medium containing delipidized serum. In contrast to the previously shown isotretinoin-specific response of cultured sebocytes in the presence of vitamin A, similar effects of isotretinoin and acitretin were obtained in its absence. This suggests different interactions of synthetic retinoids with vitamin A, possibly influencing their efficacy on the sebacceous gland

Correlations of Heavy Quarks Produced at Large Hadron Collider

We study the correlations of heavy quarks produced in relativistic heavy ion collisions and find them to be quite sensitive to the effects of the medium and the production mechanisms. In order to put this on a quantitative footing, as a first step, we analyze the azimuthal, transverse momentum, and rapidity correlations of heavy quark-anti quark ($Q\overline{Q}$) pairs in $pp$ collisions at $\cal{O}$($\alpha_{s}^{3}$). This sets the stage for the identification and study of medium modification of similar correlations in relativistic collision of heavy nuclei at the Large Hadron Collider. Next we study the additional production of charm quarks in heavy ion collisions due to multiple scatterings, {\it viz.}, jet-jet collisions, jet-thermal collisions, and thermal interactions. We find that these give rise to azimuthal correlations which are quite different from those arising from prompt initial production at leading order and at next to leading order.Comment: 26 pages, 15 figures. Three new figures added, comparison to experimental data included, abstract and discussion expande

Abstracts of contributed papers. Sixth international conference on high- energy physics and nuclear structure, Santa Fe and Los Alamos, NM, June 9--14, 1975

Abstracts of contributed papers are assembled under the following headings (number denotes the number of abstracts in the section): pi p and pi d interactions (10); $pi$ nucleus theory (33); intermediate isobar calculations (8); $pi$-nucleus interactions (25); stopping muons (44); exotic atoms and condensed nuclear states (28); nucleus-nucleus interactions (31); nuclear structure and hypernuclei (7); nucleon-nucleon interactions (24); e- and $gamma$- nucleus interactions (29); weak interactions (17); high energy collisions (13); heavy ions (22); instrumentation (8). (SDF

Strangeness, Charm and Beauty in Quark Matter: SQM 2007 Experimental Overview

This paper aims at providing an experimental overview of the Strangeness in Quark Matter 2007 ConferenceComment: Proceedings of Strangeness in Quark Matter 2007, submitted to Journal of Physics