Individual Bags Research Articles

Cystic fibrosis genotyping by direct PCR analysis of Guthrie blood spots.

In the United States the most common cystic fibrosis (CF) alleles known are F508, G551D, G542X, R553X, and N1303K. These mutations comprise approximately 85% of U.S. CF alleles, and their detection along with analysis of XV-2C and KM-19 restriction fragment length polymorphisms (RFLPs) can enable the determination of CF status. To facilitate studies for determining CF carrier status, we developed methods to detect each of these mutations and RFLPs by direct PCR amplification of dried blood spots collected on newborn screening (Guthrie) cards. Following collection, samples were protected from contamination by individual plastic bags. One-mm2 segments of filter paper were added directly to 100-microliters PCR reactions containing 1/16 mM spermidine. Three initial cycles at 96 degrees C, then 55 degrees C, for 3 min were performed to free DNA and minimize inhibition by other related materials. Next, 1 unit of Taq polymerase was added and a 2-min extension was carried out at 72 degrees C, followed by 33 amplification cycles using denaturing, annealing, and extension temperatures and times optimal for each primer set. Then, 35 microliters of each reaction was run on 8% acrylamide gels directly or 1% agarose gels following digestion; genotypes were inferred by ethidium bromide staining of gels. Guthrie blood spots of 250 CF probands and their parents were screened and the frequencies of all five mutations as well as the XV-2C KM-19 RFLP haplotypes were determined.(ABSTRACT TRUNCATED AT 250 WORDS)

Extension of Muskmelon Storage through the Use of Hot Water Life Treatment and Polyethylene Wraps

Trials were conducted in California to evaluate techniques to extend storage life of netted muskmelons (Cucumis melo L.). The use of polyethylene bags, either as individual melon wraps or as liners for 18-kg commercial cartons, minimized water loss and associated deterioration of the fruit. Individual bags and carton liners were equally effective. A 3-minute dip in 60C water effectively checked surface mold development on wrapped fruits. Lower temperature and/or shorter exposure treatments were less effective. When applied in addition to hot water treatment, imazalil fungicide did not confer significant additional benefit. The combination of polyethylene bags and hot water treatment maintained high quality, marketable fruit for at least 28 days of storage at 3C,

Pilot and Field-Scale Uranium Lysimeter Studies at the Oak Ridge Y-12 Plant

ABSTRACTField- and pilot-scale uranium leaching facilities (lysimeters) have been constructed at the Oak Ridge Y-12 Plant to investigate the rate of uranium (U) leaching and the residual U concentration that can be expected when low level radioactive waste (LLW) is buried in landfills. Current plans are to load three large standard column lysimeters with compacted production trash (blotter, waste wipes, paper etc.) and apply groundwater to the surface of the lysimeters.Several issues had to be addressed before the field lysimeters could be loaded with the LLW. Predominate among these concerns was how to adequately characterize the waste placed in the lysimeters (∼ 10 yd3 waste per lysimeter) and how to effectively collect in situ leachate samples from compacted wasteforms in the absence of soil. Pilot scale studies revealed that monitoring individual bags (30 gal) of LLW with a waste curie monitor would be sufficient to determine the initial U loading and that conventional suction candles would perform adequately within the compacted waste for extended time periods if they are installed properly. In the pilot leaching studies, the highest U concentration (∼ 0.2 mg/l) in the leachate was observed during the first month of leaching, before active biological decomposition processes became dominant making the lysimeter anoxic. After the initial oxic flushing, U concentrations in the leachate became very low (mean = 0.021 mg/l).

The effect of dry matter content on the preservation of big hale grass silages made during the autumn on commercial farms in South Wales 1983‐87

AbstractA total of eighty‐nine big‐bale (BB) silages made on commercial farms in South Wales during the autumn in 1983‐87 were analysed to discern the effect of dry matter (DM) content on fermentation. Silages were made predominantly in late September, during fine weather from permanent pasture or perennial ryegrass pastures, which had not been grazed for 9 weeks. On average 7·8 ha of pasture were cut; most farmers attempted to pre‐wilt grass for an average of 36 h prior to ensilage in individual plastic bags. Silage making was usually completed within 4 d of starting to cut. Silage ammonia‐N content was inversely correlated with DM content. The results indicated that a DM content of about 280 g kg−1 was needed to produce well‐preserved silage with an ammonia‐N content of 100 g (kg total N)−1. Silages were, therefore, generally poorly preserved because the DM increase from wilting was only 2·3 g kg−1 h−1.

Optimization of plastic covers for stack silos

Recently introduced silage conservation methods rely on polyethylene film as a barrier against air infiltration. Round bale silage stored in 0·0100 cm thick individual bags requires about 5·5 kg of plastic per tonne of dry matter; stack silos covered with a 0·0150 cm thick film require 1·3 kg of plastic per tonne of dry matter. The quality of plastic used for stack silos is very important to limit respiration loss in the large mass being protected. A theoretical model is developed to predict the total cost of plastic and respiration losses due to air infiltration the film. The optimal thickness (at minimum cost) is derived as a function of storage period, silage density and dry matter content, film permeability, and the relative value of plastic and silage. Simulation results indicate that monthly respiration losses vary between 2·4 and 0·16% for polyethylene thicknesses between 0·0025 and 0·0400 cm. Experimental data from small silage bags showed monthly loss levels of 0·2% under a perfect seal and 0·7% under an imperfect seal (one hole of 1 cm diameter). The model predicted that commercially available thicknesses of 0·0100, 0·0150 and 0·0200 cm are optimal for storage periods of 3, 7 and 12 months respectively. The total cost curve is relatively flat near the optimal thickness; this suggests that it would be wise to choose the closest available size above rather than below the optimum to take advantage of the greater physical resistance to tear and puncture of thicker film.

Effect of enteral feeding bag composition and freezing and thawing upon vitamin stability in an enteral feeding solution.

The effect of enteral feeding bag composition and freezing and thawing upon the stability of riboflavin and vitamins A and E in an enteral feeding solution was tested. Feeding bags composed of either polyvinyl chloride or polyethylene were filled with an enteral feeding solution. The samples were frozen for 3 months, thawed in warm water, and allowed to stand in room temperature for 12 hr. Samples for vitamin analysis were obtained prior to freezing, upon thawing, and at 12 hr after thawing. No significant differences in vitamin stability due to bag composition or time were seen. These results support the viability of the concept of mixing large batches of enteral feeding solution, and freezing aliquots in individual feeding bags for later use.

Preparation of pooled cryoprecipitate for treatment of hemophilia A in a home care program.

Cryoprecipitate is used infrequently in home therapy for patients with hemophilia A since freezer storage is required and resuspension and pooling of thawed cryoprecipitate is cumbersome. We evaluated procedures for preparation of cryoprecipitate in an "open system" so that four to six bags of cryoprecipitate could be pooled after production and refrozen for home therapy. Factor VIII activity for pooled cryoprecipitate was 132 +/- 30 (mean +/- SD), 125 +/- 45, and 145 +/- 47 units per bag pooled in three separate studies. Cultures from cryoprecipitate pools and individual cryoprecipitate bags did not show contamination in the "open system" or with the water bath thawing procedure. The mean increment in factor VIII activity per unit per kg infused was 0.02 units per ml and the mean half-life was 10.5 hours in three patients with hemophilia A. Pooled cryoprecipitate was shown to be clinically efficacious and acceptable for use in home care programs for hemophilia A.

Nuclear structure in the light of modern particle physics

Within the framework of the conventional boson theory of nuclear matter, internal excitation of the nucleons plays a decisive rôle in the determination of nuclear binding. On the other hand, the existence of these excited states is due to the internal quark-gluon structure of the nucleons. It is pointed out that the bag models which describe this structure in a simplified way are in contradiction with the conventional nuclear theory. In order to find a way out of this discrepancy it is suggested that it might be worthwhile to investigate an “overall” bag structure of the nucleus in which the individual nucleon bags are to some extent dissolved into quark matter. The relatively strong internal excitation of the nucleons in conventional theory already points in this direction.

Cryopreserved red blood cells for pediatric transfusion. Frozen storage of small aliquots in polyvinyl chloride (PVC) plastic bags.

Human nonrejuvenated and rejuvenated red bood cells were prepared for cryopreservation and subsequent pediatric transfusion. Glycerol was added to the red blood cells in the primary polyvinyl chloride plastic collection bag to achieve a concentration of 40 per cent W/V. The red blood cells were concentrated by centrifugation, and the supernatant glycerol was discarded. Each glycerolized unit was divided into four equal aliquots in the individual 600-ml bags of a dry quadruple polyvinyl chloride plastic system, and each aliquot was frozen and stored at -80 C. After thawing, sodium chloride solutions were used to wash the aliquots in the IBM Blood Processor 2991-1 or 2991-2 or the Haemonetics Blood Processor 115, and the washed aliquots were stored in a sodium chloride-glucose-phosphate solution at 4 C for 24 hours. Freeze-thaw recovery of the red blood cells was about 97 per cent, and freeze-thaw-wash recovery was about 84 per cent. Twenty-four-hour posttransfusion survival values were about 92 per cent for both nonrejuvenated and indated-rejuvenated red blood cells. Nonrejuvenated red blood cells, those frozen within three to five days of collection without biochemical modification, had normal oxygen transport function at the time of transfusion; rejuvenated red blood cells, those biochemically treated with PIGPA Solution A after three to five days of storage at 4 C, had improved oxygen transport function at the time of transfusion.

Innovations in Ferroalloy Baghouse System Design

System design used by a typical ferroalloy producer is reviewed, with special emphasis on shaker cleaning of Nomex fabric in large structural baghouses. The use of air curtains at the furnace hoods, duct size venturi for flow measurement, and other techniques are described to permit evaluation of individual bags as well as complete compartments of bags. A unique hook-up of magnehelic gauges provides an instant assessment of the performance of each compartment to assist operators in achieving optimum operation. A critique on waste heat recovery, gas coolers, and induced draft fans on dirty gas service is included.

RATES OF DIGESTION OF SWALLOWED AND UNSWALLOWED DRIED GRASS IN THE RUMEN

Nylon bags containing samples of dried grass and of the same grass which had been chewed and impregnated with saliva were placed in the ventral rumen sacs of two steers. The rates of digestion of the dry matter, crude fiber, crude protein, and ash were measured by removing individual bags at various time intervals up to 72 hours. The amounts of dry matter, protein, and ash digested during the first hour were much greater than the amounts digested in any subsequent 1-hour period. This was attributed to an initial rapid leaching of soluble material. The digestion of the dry matter, protein, and ash in the swallowed grass during the first hour was considerably greater than in the unswallowed grass, and differences were still present 13 hours later. The digestion of the insoluble fiber was negligible until the fourth hour after the samples were placed in the rumen. Between the fourth and the fourteenth hours the digestion of the fiber in the swallowed grass was more rapid than that in the unswallowed grass. It was concluded that the crushing and ensalivation which occurs during the eating of dried grass increases its subsequent rate of digestion in the rumen.

Keeping Quality of Pacific Coast Dogfish. II

Pacific coast dogfish (Squalus suckleyi) were stored in individual polyethylene bags at 0, 5 and 10 °C; a control group of fish was iced. Viable bacterial counts, pH, ammonia and trimethylamine were determined daily. Pronounced ammoniacal odours were noted with only a few samples and were generally strongly masked by putrid odours.