Aquaculture Techniques for Crappie,Pomoxis spp., Culture

Extensive crappie, Pomoxis spp., culture has been practiced for decades, however, knowledge of crappie aquaculture methods is limited. The following review synthesizes existing research on crappie aquaculture and identifies knowledge gaps where further research is needed. Topics such as life history, tank culture, feeding, reproduction and spawning, larval rearing, transport and harvest, triploidy, hybridization, and out‐of‐season spawning were reviewed. The outcome is a better understanding of hindrances preventing crappie aquaculture development in the past, particularly tank culture and induced spawning techniques, and specific research objectives with potential to enhance recreational and commercial production.     

Review of chromatographic methods for chloramphenicol residues in milk, eggs, and tissues from food-producing animals

Although chloramphenicol is not approved for use in food-producing animals in the United States, this broad spectrum antibiotic has been widely used to treat diseases in such animals including the lactating dairy cow. Extremely low ophthalmologic doses of chloramphenicol are known to cause aplastic anemia in humans. The residues in meat, milk, and eggs intended for human consumption cause particular public health concern because the bone marrow aplasia is not dose dependent. Furthermore, chloramphenicol, a known inhibitor of protein synthesis, also retards erythropoiesis, a condition that is dose dependent and may cause allergic hypersensitivity reactions. This paper is a review of sensitive methods that use gas, liquid, thin layer, and simple column chromatography as both determinative and cleanup steps for detecting and quantitating chloramphenicol in edible animal tissues, milk, and eggs.     

Laboratory and on‐farm evaluation of low‐cost salt mixtures for use during salinity acclimation and the nursery phase of Pacific white shrimp (Litopenaeus vannamei)

The current study evaluates the efficacy of a low‐cost salt mixture (LCSM) to replace expensive reconstituted sea salt (RSS) in the salinity acclimation and nursery phase of Pacific white shrimp under laboratory and farm conditions. LCSM was formulated to yield sodium, potassium, calcium and magnesium concentrations closely comparable to that of diluted seawater. Laboratory‐based nursery trials were conducted at 2, 6 and 15 g/L salinities, incrementally replacing RSS with LCSM (25%, 50%, 75% and 100%) at four replicates per treatment. Thirty postlarvae were reared for 7 days in 24‐L aquaria during the 2 and 6 g/L trials, while the nursery trial for 15 g/L salinity was conducted for 21 days with 400 postlarvae stocked in 150‐L tanks. On‐farm evaluation of LCSM was carried out in two tank‐based systems installed on levees adjacent to shrimp production ponds. RSS was incrementally replaced with LCSM (0%, 50%, 75% and 100%) and 100 postlarvae stocked into each 800‐L tank. Salinity acclimation was done from 30 g/L to 6 or 1.5 g/L within 2–3 days by pumping water from adjacent shrimp production ponds. Following salinity acclimation, the S4 system maintained flow‐through at 1.5 g/L, while N10 system was maintained static at 6 g/L salinity. At the conclusion, no significant differences were observed for either survival or growth of shrimp postlarvae between RSS and LCSM treatments at all salinities examined. Results reflect the potential use of LCSM to replace RSS, which could be an excellent solution to bring down the cost of production in inland shrimp aquaculture.     

A high-resolution radiation hybrid map of the human genome draft sequence

We have constructed a physical map of the human genome by using a panel of 90 whole-genome radiation hybrids (the TNG panel) in conjunction with 40,322 sequence-tagged sites (STSs) derived from random genomic sequences as well as expressed sequences. Of 36,678 STSs on the TNG radiation hybrid map, only 3604 (9.8%) were absent from the unassembled draft sequence of the human genome. Of 20,030 STSs ordered on the TNG map as well as the assembled human genome draft sequence and the Celera assembled human genome sequence, 36% of the STSs had a discrepant order between the working draft sequence and the Celera sequence. The TNG map order was identical to one of the two sequence orders in 60% of these discrepant cases.     

Alteration of stimulus-specific guard cell calcium oscillations and stomatal closing in Arabidopsis det3 mutant

Cytosolic calcium oscillations control signaling in animal cells, whereas in plants their importance remains largely unknown. In wild-type Arabidopsis guard cells abscisic acid, oxidative stress, cold, and external calcium elicited cytosolic calcium oscillations of differing amplitudes and frequencies and induced stomatal closure. In guard cells of the V-ATPase mutant det3, external calcium and oxidative stress elicited prolonged calcium increases, which did not oscillate, and stomatal closure was abolished. Conversely, cold and abscisic acid elicited calcium oscillations in det3, and stomatal closure occurred normally. Moreover, in det3 guard cells, experimentally imposing external calcium-induced oscillations rescued stomatal closure. These data provide genetic evidence that stimulus-specific calcium oscillations are necessary for stomatal closure.     

Antibody to nuclear material eluted from isolated spleen vessels in systemic lupus erythematosus

Splenic blood vessels were isolated from surrounding cells by treatment with trypsin and the use of ultrasound. This procedure retained vascular-bound immunoglobulins which were recovered by acid elution of vessels isolated from a patient with systemic lupus erythematosus. These eluted immunoglobulins reacted with material from cell nuclei as demonstrated by immunofluorescence.     

木霉菌对大豆幼苗生长的影响及在根部定殖研究

分析木霉菌MM35、MM7、MM8、MM9、ZT1、ZT2对大豆幼苗生长的影响,其中MM7、ZT1和ZT2的孢子悬浮液在104cfu·mL-1和105cfu·mL-1的浓度下对大豆发芽不会产生影响,其代谢产物对大豆发芽没有抑制作用.盆栽试验表明:木霉菌MM7不对大豆幼苗产生致病性,且使株高增加13%.盆栽灭菌条件下研究木霉MM7在大豆根部定殖能力表明:木霉菌MM7可随大豆主根和侧根的生长而不断繁殖,且在土壤表面以下0～5 cm大豆根际土壤中MM7孢子数量明显高于5～10 cm和10～15 cm的土层,随着生育时间的延长,不同土层大豆主根和侧根表面木霉菌数量均可在12 d～22 d之间达到最高值,在根的表面形成保护层,对于大豆苗期病原菌起到一定抑制作用.