Nylon Bolting Cloth Research Articles

Zooplankton Abundance and Growth of Carps in Farm-Ponds of Different Agro-Climatic Zones of Karnataka

Availability of planktons / natural fish food plays an important role in getting better growth of fish from farm ponds. Study was carried out to evaluate the zooplankton community and growth performance of Carp fishes in farm ponds of coastal and malnad agro-climatic regions of Karnataka. All the ponds were manured with cowdung and poultry manure @ 2000 kg/ha. for the production of planktons. Catla, Rohu and common carp fingerlings were stocked in all the ponds @ 10,000 nos. /ha in 1:1:1 ratio and fishes were fed with groundnut oil cake and rice bran (in 1:1 ratio) @ 5% of the body weight every day. The water samples from all the ponds were collected and filtered for zooplanktons using nylon bolting cloth (60 µm). The growth of fishes in terms of weight was recorded. The analyzed zooplankton planktons were classified into 5 class’s viz., Rotifera, Protozoa, Copepoda, Cladocera and Ostracod. Among zooplanktons observed, copepod contributed maximum to zooplankton community followed by rotifers, cladocerans and ostracod. In coastal ponds the average maximum number of zooplankton 10,368 Cells/m3 and minimum number of 176 Cells/m3 were observed. In Malnad ponds the average maximum number of zooplankton 21,797 Cells/m3 and minimum number of 1579 Cells/m3 were observed. The average maximum growth of Catla, Rohu and Common carp was observed in coastal ponds were 884.42, 640.1 and 692.27 gms respectively and in Malnad farm ponds 1080.71, 954.19 and 1023.18 gms respectively. Use of cowdung and poultry manure in combination was found useful for getting better growth in farm ponds of both the regions.

Immobilization of Aspergillus sp. on nylon bolting cloth for production of xylanase

Aspergillus sp. 5 and Aspergillus sp. 44, isolated from compost manure, were immobilized on a 400-mesh nylon bolting cloth. In shake flasks under a given set of conditions, the immobilization resulted in an absolutely clear residual broth, when compared with that containing freely suspended cells confirming complete adherence of the cells. It was found that this method of immobilization was simple and had no detrimental effects on the growth or activity of the cells. The enzyme productivity of immobilized Aspergillus sp. 5 was 1.68-fold higher than that of freely suspended cells, while for the case of Aspergillus sp. 44 the difference in productivity between freely suspended and immobilized cells was not significant. In repeated batch fermentation of both immobilized Aspergillus sp. 5 and Aspergillus sp. 44, the same biocatalyst yielded 103.93%, 97.02%, 51.8% and 97.52%, 72.08% xylanase activity in consecutive cycles.

The effect of management protocols for juvenile carp ( Cyprinus carpio) culture on life history responses of a zooplankton food source, Moina micrura (Kurz.)

Three systems of carp ( Cyprinus carpio) culture (live food system, manured system, and control system) were used to examine environmentally dependent life history characteristics of zooplankton, Moina micrura. Twelve culture tubes with one neonate of M. micrura per tube and covered by nylon bolting cloth of 75 μm mesh size were suspended in situ in each culture system. Each culture tube was examined daily to evaluate life history patterns. Time to first reproduction ranged from 4 to 7 days in the control and manured systems and 3 to 5 days in the live food system. Mean longevity, net reproductive rate, average generation time, as well as total offspring production per female, were distinctly higher for the live food system than for the manured or control systems. Interactions between chemical oxygen demand, dissolved oxygen, phosphate levels and primary productivity resulting in optimal conditions were responsible for large variations in life history characteristics of M. micrura among the culture systems.

Sieving Techniques in Palynological Sample Processing with Special Reference to the MRA System

Sieving Techniques in Palynological Sample Processing with Special Reference to the MRA System

Alzheimer paired helical filaments: bulk isolation, solubility, and protein composition.

A method has been developed for the bulk isolation of Alzheimer neurofibrillary tangles (ANT) of paired helical filaments (PHF) from histopathologically confirmed cases of Alzheimer disease/senile dementia of the Alzheimer type (AD/SDAT). The fresh or frozen autopsied cerebral cortex affected with Alzheimer neurofibrillary changes is dissociated by homogenization and sieving through nylon bolting cloth and the ANT are separated by a combination of sucrose discontinuous density gradient centrifugation, glass bead column chromatography, and sodium dodecyl sulfate (SDS) treatment. The isolated ANT produce red-green birefringence when viewed through polarized light after staining with Congo red. Ultrastructurally, the isolated PHF are well preserved and have the dimensions of the PHF seen in situ. Two major Populations of ANT which exist in different proportions in AD/SDAT brains are identified on the basis of their solubility in SDS. The ANT I and the ANT II are soluble and insoluble respectively on treatment with 2% SDS at room temperature for 5 min. Solubilization of the ANT II requires several repeated extractions with a solution containing 10% each of SDS and beta-mercaptoethanol (BME) at 100 degrees C for 10 min. Sonication of the ANT II greatly facilitates their solubilization. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) of the isolated ANT reveals the presence of two major polypeptides with molecular weights (MW) of 62,000 and 57,000, several minor polypeptides with MW below 57,000, and a significant amount of material not entering the stacking and the resolving gels. Re-electrophoresis of polypeptides extracted from various areas of the resolving gel or of the material which does not enter the gel generates the same polypeptide profile as on the first gel, suggesting that the PHF material which does not enter the gel may result from the reaggregation of the polypeptides that enter the resolving gel. None of the polypeptides that enter the resolving gel. None of the polpeptides observed in the isolated PHF comigrate in the SDS-PAGE with any of the neurofilament polypeptides, tubulin, actin, or myosin.

Studies on neurotransmitter-stimulated phospholipid metabolism with cerebral tissue suspensions: A possible biochemical correlate of synaptogenesis in normal and undernourished rats

The phenomenon of neurotransmitter-stimulated incorporation of 32Pi into phosphatidic acid and inositol phosphatides (neurotransmitter effect) in developing brain was studied in vitro as a possible measure of synaptogenesis. While the neurotransmitter effect was not observed with brain homogenates, highly consistent and significant effects were noted with brain tissue suspensions obtained by passing the tissue through nylon bolting cloth. The magnitude of the effect decreased with the increase in mesh number. Maximum stimulations obtained with the 33 mesh adult brain cortex preparations (mean±S.E.M. of6experiments) were203 ± 8%, 316 ± 11 % and150 ± 8% with 10 −3 M acetylcholine (ACh) + 10 −3 M eserine; 10 −2 M norepinephrine (NE) and 10 −2 M serotonin (5-HT), respectively. Experiments with developing rat brain at 7, 14 and 21 days of age showed that the neurotransmitter effects due to ACh, NE and 5-HT increase progressively in different regions of the brain but that there are marked regional differences. It is suggested that the neurotransmitter effect is a valid biochemical correlate of synaptogenesis. In rats undernourished from birth t0 21 days of age, by increasing the litter size, the neurotransmitter effect with ACh, NE or 5-HT was not altered in the cortex but was significantly reduced in the brain stem. In cerebellum the effects due to ACh and NE were significantly altered, while that with 5-HT was unaffected. It is concluded that cholinergic, adrenergic and serotonergic synapses are relatively unaffected in the cortex but are significantly affected in the brain stem by undernutrition. In the cerebellum of undernourished rats the adrenergic and cholinergic, but not serotonergic systems, are altered.

Photosynthesis and light and dark respiration in freshwater algae

Rates of gas exchange were measured for cultures of Chlorella pyrenoidosa, Chlamydomonas reinhardtii, and Anabaena flos-aquae, which were suspended in moist air on an artificial leaf made with nylon bolting cloth. A 14CO2–12CO2 technique was used to measure net and gross photosynthesis and light and dark respiration in air or nitrogen. Rates of gas exchange on the artificial leaf were equal to maximum rates obtainable for the same algae suspended in culture medium. Rates were stable, and the artificial leaf could be maintained for many hours.The algae did not exhibit conventional photorespiration. However, they did have a variable rate of light respiration that frequently equalled, but did not exceed, the rate of dark respiration. This light respiration appeared to be a continuation of normal dark respiration in light. It was affected by CO2 concentration, declining to zero if the cells were illuminated in the absence of CO2. Unlike higher plants, recent photosynthate is not a substrate of light respiration in these algae.

Uptake and relase of (14C)adenine derivatives at beds of mammalian cortical synaptosomes in a superfusion system.

Abstract(1) Synaptosomal fractions from guinea pig neocortical dispersions prepared in sucrose solutions were deposited from saline media as ‘beds’ on nylon bolting cloth. When incubated with 0.5–10 μm‐[14C]adenine or adenosine in glucose bicarbonate salines, uptake of 14C from adenosine proceeded at about four times the rate of uptake of [14C]adenine. This contrasted with the relative uptake of the two compounds to neocortical tissue slices or to beds made from mitochondrial fractions, where uptake was similar with the two precursors. Uptake of both precursors to synaptosome beds was much greater than uptake of inosine.(2) Synaptosome beds, [14C]adenosine‐loaded, contained 88 per cent of the 14C as 5′‐adenine nucleotides, the remainder being present as cyclic AMP, inosine, hypoxanthine and adenosine. When superfused, the 14C output consisted mainly of adenosine, inosine and hypoxanthine, with some 7 per cent of 5′‐nucleotides and 4 per cent of cyclic AMP.(3) Electrical pulses and the addition of 50 mm‐KCl each increased the efflux of 14C from superfused [14C]adenosine‐loaded beds. The superfusates issuing after excitation contained the same 14C‐labelled compounds as issued before, with a small increase in the proportional yield of adenosine. The additional output of 14C following electrical pulses was diminished by about 50 per cent by 0.5 μm‐tetrodotoxin while that following KCl was not affected; it was however prevented when the superfusing fluids were free of Ca2+.

Comparative Effectiveness of the Standard Surber Sampler and a Hydraulic Modification for Estimating Bottom Fauna Populations

FOR MORE THAN 30 YEARS, aquatic biologists have been using the Surber [10] square-foot bottom sampler to obtain qualitative and quantitative measurements of stream bottom fauna. This sampler consists of two brass frames, each 1 foot square, hinged together so that they form a right angle when extended. One frame then fits over the square foot of streambed to be sampled, and the other is provided with a net into which organisms drift as they are dislodged from the streambed. The net generally is constructed from 23-mesh silk or nylon bolting cloth. In practice, the biologist hand stirs the bottom material within the square-foot area to a depth of a few inches. The dislodged organisms then drift into the collecting net. A major disadvantage of this procedure is the time required to obtain a thorough scrubbing of the substrate. A lesser disadvantage, that of the numbing effect on hands and arms after long periods of exposure to cold water, can be partially overcome by full-arm-length rubber gauntlets. Fishery biologists have used hydraulic units for the past several years to sample salmon eggs and preemergent fry in streambed gravels [7]. These samplers consist of a portable centrifugal pump (usually mounted on a packboard or a small raft), a water_ intake hose, and an outlet or exhaust hose, terminating in a 3-foot length of pipe. A jet of mixed air and water, regulated in force by the pump throttle, is controlled by aiming the pipe into the sample area. This water force loosens and stirs up gravel and the associated fish and invertebrate life, which wash down into a collecting net immediately below the sample area. At times, numerous aquatic insects and other bottom organisms have been observed in these egg and fry samples.

Ribonucleic acid synthesis in nuclei isolated from Musca domestica

Nuclei isolated from adult houseflies by centrifugation in 2.2 M sucrose-3 m M CaCl 2 and filtration through 10-μm. pore nylon bolting cloth have an RNA/DNA ratio of 3.08. This ratio is 4.05 in nuclei isolated from larval tissues. Nuclei catalyse the incorporation of labelled nucleoside triphosphates into acid-insoluble RNA. The RNA polymerase of nuclei depends on the presence of four nucleoside triphosphates and either Mn 2+ or Mg 2+. RNA synthesis is inhibited by DNase, RNase, and actinomycin D. DDT added in vitro has no effect on the polymerase activity. The reaction product from nuclei isolated from adult insects and in the presence of Mg 2+ is high in adenine and uridine, with a U/G ratio of 1.77. In the presence of Mn 2+ the U/G ratio decreases to 1.33. The product from larval nuclei in the presence of Mg 2+ is high in guanine, whereas in the presence of Mn 2+ it is high in uridine. Nuclear preparations from insects pretreated with DDT have a higher polymerase activity than control preparations. The increase in activity is only evident during the first hour of treatment.

Hippelates collusor (Diptera: Chloropidae) as a Host for Four Species of Parasitic Hymenoptera in Southern California

During 1961–62 four hymenopterous parasites of the eye gnat, Hippelates collusor (Townsend), were discovered in the semiarid agricultural regions of southern California. These parasites were found by field-exposing host Hippelates pupae for several days between discs of nylon bolting cloth for predator protection. Three of the parasites, Phaenopria occidentalis Fouts, Spalangia drosophilae Ashmead, and Eupteromalus nidulans Thomson, were successfully cultured in the laboratory and also studied in field releases. The fourth, Trichopria n. sp., died before propagation could be attempted. In field releases of parasites S. drosophilae was the most efficient species in seeking Hippelates pupae in the environments studied.

A Colchicine, Hypotonic Citrate, Squash Sequence for Mammalian Chromosomes

The method was developed for bone marrow of mice but is applicable to other tissues and other species of small mammals. Mice are injected intraperitoneally with 0.5 ml of 0.025% colchicine solution and killed 1 hr afterwards. The femurs are dissected out rapidly, the epiphyses are removed, and the marrow is washed out of the shafts by warm hypotonic sodium citrate solution from a hypodermic syringe. Gentle aspiration of the marrow into and out of the syringe converts it into a fine suspension. The suspension is kept in the citrate solution at 37°C for 10 min. Connective tissue and bony spicules are removed by centrifuging through Nylon bolting cloth in a bacterial filtration tube, before fixing in acetic-alcohol (1:3) and staining by the standard Feulgen procedure. The cells are concentrated for each change of reagent by centrifuging slowly. The advantages of colchicine pretreatment and of working with cell suspensions are emphasized.