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At least 19 recordsLinked to original sources
PubMed1999

Response of lactating dairy cows to steam-flaked sorghum, steam-flaked corn, or steam-rolled corn and protein sources of differing degradability.

Protein sources with different degradabilities were fed to 48 lactating Holstein cows receiving 37 or 39% of dietary dry matter as steam-flaked sorghum (360 g/L), steam-flaked corn (360 g/L), or steam-rolled corn (490 g/L) in a 3 x 2 factorial arrangement of treatments. Cows were fed an alfalfa-based diet with 7% soybean meal or 5% of an animal-marine protein blend and 37 or 39% grain. Although not significant, cows fed flaked grain yielded a mean of 1.5 kg/d more milk than did those fed rolled grain. Gross feed efficiency was not affected by grain processing or protein source, but diets with the animal-marine protein blend had 9% higher estimated net energy for lactation than did diets with soybean meal. The greater gains in body weight and increased digestibility of the diets with the animal-marine protein blend verify the higher energy concentration of those diets. Yield of milk protein was increased by flaked grain or the animal-marine protein blend, and flaked grain increased percentages of lactose and solids nonfat. Increasing the ratio of rumen-degradable starch to rumen-degradable protein increased milk protein content and yield linearly and increased contents of lactose and solids nonfat. A linear response of dry matter, organic matter, crude protein, and starch digestibilities was observed as the ratio of rumen-degradable starch to rumen-degradable protein increased. These data show improved performance of dairy cows fed a high rumen-undegradable protein source with diets high in rumen-degradable starch from steam-processed grains.

Animal Feed↗
PubMed2002

Splanchnic and mammary nitrogen metabolism by dairy cows fed steam-rolled or steam-flaked corn.

Objectives were to determine net release or uptake of a-amino N, ammonia N, and urea N across portal-drained viscera, liver, splanchnic, and mammary tissues of lactating Holstein cows (n = 6; 109 +/- 9 d in milk) fed alfalfa hay-based total mixed rations (TMR) containing 40% steam-rolled or steam-flaked corn grain. The TMR were offered at 12-h intervals in a crossover design. Blood samples were obtained from indwelling catheters in portal, hepatic, and mammary veins and mesenteric or costo abdominal arteries, every 2 h for each cow and diet. Steam-flaked compared with steam-rolled corn greatly increased in vitro starch hydrolysis (56 vs. 34%). Daily intake of dry matter (18.4 +/- 0.4 kg/d), starch, N, and net energy for lactation by cows were not altered by processing corn; neither were daily yield of milk (29.1 +/- 0.7 kg/d), fat-corrected milk, nor fat-corrected milk per dry matter intake. Steam-flaking tended to increase percent milk protein (2.97 vs. 2.82%; P = 0.07), but not yield, and decrease percent lactose (4.83 vs. 4.94) but not yield. Portal and hepatic blood flows were not affected by diet, nor were net absorption of alpha-amino N and ammonia N. Steam-flaking compared with steam-rolling increased urea N cycling to portal-drained viscera (212 vs. 87 g/d) by 140%, estimated mammary uptake and extraction ratio of alpha-amino N. Flaking versus rolling of corn improved N utilization in dairy cows by increasing urea cycling to the gut and uptake of a-amino N by the mammary gland. Higher mammary uptake of alpha-amino N (78 vs. 50 g/d) by dairy cows fed steam-flaked corn tended to increase milk protein content and may explain the previously observed effects of cows fed steam-flaked versus steam-rolled corn.

Animal Feed↗
PubMed1998

Effects of ground, steam-flaked, and steam-rolled corn grains on performance of lactating cows.

Five types of processed corn were compared to determine the effects of processing on lactational performance and nutrient digestibilities in dairy cows. Forty lactating Holstein cows averaging 160 +/- 60 d in milk were randomly divided into five groups on the basis of pretreatment milk yields and were fed diets containing 40% corn grain for 56 d. Treatments were 1) finely ground corn, 2) coarsely ground corn, 3) steam-flaked corn at a low density, 4) steam-flaked corn at a medium density, and 5) steam-rolled corn. Cows fed the diet containing steam-flaked corn at a medium density had a higher milk yield (37.1 kg/d) than did cows fed the diets containing coarsely ground corn, steam-flaked corn at a low density, or steam-rolled corn; cows fed the diet containing finely ground corn had an intermediate milk yield (35.5 kg/d). Efficiency of feed utilization was greater, and dry matter intake was lower, for cows fed the diet containing finely ground corn than for cows fed the other diets. The fat content of milk was higher for cows fed the diets containing coarsely ground corn and steam-rolled corn than for cows fed the diet containing steam-flaked corn at a medium density. Milk protein and SNF contents and yields of protein, lactose, and SNF did not differ among diets. Apparent starch digestibilities in the total digestive tract were lower for diets containing coarsely ground corn (87.4%) and steam-rolled corn (91.3%) than for the other diets (X = 96.3%). Milk yield was highest for cows fed the diet containing steam-flaked corn with a medium density. Fine grinding resulted in the greatest efficiency of feed utilization.

Animal Feed↗
PubMed1997

Effect of steam-flaked or steam-rolled corn with or without Aspergillus oryzae in the diet on performance of dairy cows fed during hot weather.

The objective of this study was to determine the effects of steam-rolled versus steam-flaked corn in the diet with or without the addition of a culture of Aspergillus oryzae on the performance of high producing dairy cows during hot summer weather. Thirty-two Holstein cows averaging 92 (+/- 60) d in milk were fed a pretreatment diet for 21 d followed by a 70-d experimental period in a completely randomized block design with a 2 x 2 factorial arrangement of treatments. Diets were 1) steam-flaked corn plus 3 g/d of A. oryzae, 2) steam-flaked corn, 3) steam-rolled corn plus 3 g/d of A. oryzae, and 4) steam-rolled corn. Intake was not affected significantly by grain processing or addition of A. oryzae. Compared with effects from steam-rolled corn in the diet, steam-flaked corn increased milk production; percentage of milk protein; yields of milk protein, lactose, and SNF; and the efficiency of conversion of dry matter to fat-corrected milk. Addition of A. oryzae tended to increase protein percentage and increased the percentage of SNF. Changes in body weight and body condition score tended to be higher, and somatic cell count tended to be lower, for cows fed the flaked corn than for cows fed the rolled corn. No interactions were significant. Treatments did not affect rectal temperatures or respiration rates; however, high mean values measured at 1400 h once weekly indicated thermal stress. These data show improved milk production from cows fed steam-flaked corn but not from those fed diets supplemented with A. oryzae.

Animal Feed↗
PubMed2002

A theoretical model of air and steam co-injection to prevent the downward migration of DNAPLs during steam-enhanced extraction.

When steam is injected into soil containing a dense volatile non-aqueous phase liquid contaminant the DNAPL vaporized within the heated soil region condenses and accumulates ahead of the steam condensation front. If enough DNAPL accumulates, gravitational forces can overcome trapping forces allowing the liquid contaminant to flow downward. By injecting air with steam, a portion of the DNAPL vapor remains suspended in equilibrium with the air, decreasing liquid contaminant accumulation ahead of the steam condensation front, and thus reducing the possibility of downward migration. In this work, a one-dimensional theoretical model is developed to predict the injection ratio of air to steam that will prevent the accumulation of volatile DNAPLs. The contaminated region is modeled as a one-dimensional homogeneous porous medium with an initially uniform distribution of a single component contaminant. Mass and energy balances are combined to determine the injection ratio of air to steam that eliminates accumulation of the contaminant ahead of the steam condensation front, and hence reduces the possibility of downward migration. The minimum injection ratio that eliminates accumulation is defined as the optimum injection ratio. Example calculations are presented for three DNAPLs, carbon tetrachloride (CCl4), trichloroethylene (TCE), and perchloroethylene (PCE). The optimum injection ratio of air to steam is shown to depend on the initial saturation and the volatility of the liquid contaminant. Numerical simulation results are presented to validate the model, and to illustrate downward migration for ratios less than optimum. Optimum injection ratios determined from numerical simulations are shown to be in good agreement with the theoretical model.

Air↗
PubMed2002

Removal of NAPLs from the unsaturated zone using steam: prevention of downward migration by injecting mixtures of steam and air.

Steam injection for remediation of porous media contaminated by nonaqueous phase liquids has been shown to be a potentially efficient technology. There is, however, concern that the technique may lead to downward migration of separate phase contaminant. In this work, a modification of the steam injection technology is presented, where a mixture of steam and air was injected. In two-dimensional experiments with unsaturated porous medium contaminated with nonaqueous phase liquids, it was demonstrated how injection of pure steam lead to severe downward migration. Similar experiments, where steam and air were injected simultaneously, resulted in practically no downward migration and still rapid cleanup was achieved. The processes responsible for the prevention of downward migration when injecting steam-air mixtures were analyzed using a nonisothermal multiphase flow and transport model. Hereby, three mechanisms were identified and it was demonstrated how the effectiveness of these mechanisms depended on the air-to-steam mixing ratio.

Air↗
PubMed1986

Comparative thermoresistance of two biological indicators for monitoring steam autoclaves. 3. Comparison performed at 121 degrees C in a hospital prevacuum steam sterilizer.

According to Pharmacopoea Nordica, steam autoclaves should be regularly monitored by a specific Swedish preparation of Bacillus stearothermophilus spores. If another biological indicator (BI) is used for such a control, it should first be calibrated against the Swedish BI (SBI) and the two BIs should be equally thermoresistant. Attest No. 1262 BI (ABI) has previously been shown to be more thermoresistant than the SBI at 134 degrees C, saturated steam. The purpose of the present study was to compare the thermoresistance of the SBI and the ABI at 121 degrees C, saturated steam and prevacuum. Seven hundred and twenty units of each BI were heat-exposed in an Emmer 760 litre prevacuum, pressure-pulsing steam autoclave. After prevacuum with steam injection (manual or automatic preconditioning), the following incremental heat exposure times were used in triplicate (20 simultaneously tested units of each BI in each cycle) according to a randomized scheme: 5, 6 1/2, 8, 9 1/2, 11, 12 1/2, 14 and 15 min. The intra-chamber pressure and temperature were continuously monitored throughout the test and equilibration cycles. The heat-exposed BI units were cultivated and read as recommended by the manufacturers. SBI and ABI showed a survival-time of 8 min and 11 min respectively, and a kill-time between 14 min and 15 min for both BIs. Thus, the ABI had the narrower survival-kill window. Probit analysis testing of the results showed that the difference in thermoresistance, at 121 degrees C, saturated steam and prevacuum between Attest No. 1262 BI and the Swedish BI mentioned in Pharmacopea Nordica was not statistically significant.

Environmental Monitoring↗
PubMedDate not supplied

Endotoxin levels in steam and reservoirs of table-top steam sterilizers.

PURPOSE: To document endotoxin levels in "Statim" cassette sterilizer reservoirs and in steam delivered to the cassette in the unwrapped instrument cycle. To document endotoxin levels in sterilizer reservoir water using different management protocols. METHODS: Endotoxin levels were determined using the Limulus Amebocyte Lysate test. Endotoxin preparations were from Escherichia coli and Ralstonia pickettii. All samples were collected in depyrogenated glassware and stored at -20 degrees C until assayed. RESULTS: The majority of water samples contained < 1.0 Endotoxin Unit (EU)/ml. The highest level found in sterilizers in clinical use was 5.3 EU/ml. Endotoxin was not detected in steam condensate within the limits of the assay. When the endotoxin level in the reservoir water was experimentally enhanced to 200 EU/ml, cassette steam condensate endotoxin levels were from 0.5% to 5% of the reservoir level. Daily and weekly emptying of the cassette reservoir consistently yielded low endotoxin levels as did monthly emptying, but with the latter there was a trend toward higher levels that favors weekly emptying as a precautionary measure. CONCLUSIONS: Endotoxin levels in the reservoirs of 23 sterilizers involving 240 samplings were never high enough to yield detectable endotoxin levels in steam in the sterilizer cassette. Regular weekly emptying of sterilizer reservoirs would eliminate the risk of endotoxin transfer during steam sterilization.

Ambulatory Care↗
PubMed1975

[Determination of the true digestibility of amino acids in variously prepared potatoes in growing pigs. 1. Freshly steamed potatoes and silage made from steamed potatoes].

Freshly Steamed Potatoes of 6 varieties were investigated. With 3 varieties the true N and amino acid digestibilities were found to be in good agreement, while great variations were found in potatoes of the other 3 varities so that it appears to be a matter of some doubt whether the true amino acid digestibility could, in the case of potatoes, be reliably derived from data on the true N digestibility. Differences in the true amino acid digestibility data were found between the varities of potatoes grown in different years. A positive trend was found to exist in the relationship between the absolute amino acid content and true digestibility. The true lysine digestibility of freshly steamed potatoes varies between 76-90%, the average percentage being about 80%. The true methionine digestibility was found to vary within still wider limits, although the average percentages was also about 80%. Values established for the true cystine digestibility ranged from 80% to 90%. The true amino acid digestibility data did not provide a sufficiently reliable basis for making conclusions as to the existence of a limiting amino acid. Both the lowest value for true digestibility and the greatest variations were found in the case of the amino acids alanine, tyrosine, and methionine. It was observed that silage made from steamed potatoes had a lower true digestibility of N than steamed fresh potatoes although the value for true amino acid digestibility were the same, with the exception of methionine and cystine.

Amino Acids↗
PubMed2003

Propane oxidation and steam reforming over Pd/LaFe(0.8) Co(0.2) O3 catalyst: effects of the reactant composition and steam.

The effects of reactant composition and steam on propane combustion over Pd/LaFe(0.8) Co(0.2) O3 catalyst were investigated. Propane conversion and the oxidation state of palladium were strongly affected by the redox ratio of reactants. Higher propane conversion could be obtained under rich conditions and explained as a complex balance between oxidation and steam reforming. Water produced in the oxidation could promote the propane conversion by steam reforming. However, the presence excess steam would bring about inhibition.

Catalysis↗
PubMed1987

Sterilization. Steam sterilizers and steam sterilizer standards--Australia.

The objectives that I have adopted for my contribution are: To describe the "environment" surrounding steam sterilization in Australian Hospitals; To describe the origin and features of current Australian steam sterilizer Standards; and To discuss some directions for future changes to hospital steam sterilization in Australia.

Australia↗
PubMed1975

Steam sterilization: a comparison of Steam-Clox and some european biological indicators.

Results of a study of the reaction of a chemical indicator (Steam-Clox) and of two biological indicators exposed to steam sterilization with varying amounts of air introduced with the steam, indicate that the chemical indicator is capable of detecting significantly smaller amounts of air than either of the biological indicators tested.

Indicators and Reagents↗
PubMed1979

[On the importance of the steam trap to the efficient sterilization of solutions in stored blood bottles by saturated steam under pressure (author's transl)].

Biological tests with soil samples were performed to fix the sterilization time for a new steam sterilizer. These tests yielded repeatedly positive spore findings despite modifications of the conditions of sterilization. Having excluded a series of possible sources of trouble, the authors stated that the quality of the steam was the assignable cause. After restoration of the functionality of the steam traps, the biological tests yielded negative results also under normal conditions of sterilization.

Drug Packaging↗
PubMed1985

Comparative thermoresistance of two biological indicators for monitoring steam autoclaves. 2. Comparison performed at 134 degrees C in a hospital prevacuum steam sterilizer.

The thermoresistance of various lots of two biological indicators (BIs) for steam sterilization control, a Scandinavian BI (SBI) and the Attest BI (ABI), were compared during sterilization cycles in a hospital prevacuum (pressure-pulsing) steam autoclave at 134 degrees C, saturated steam. ABI No. 1242, ABI No. 1262 (its replacement) and incremental heat exposure times between 0 s and 180 s were used. The intrachamber temperature and pressure were continuously measured and monitored throughout the sterilization cycles. The results showed that both of the ABIs were more thermoresistant than the SBI, giving 33.1% (ABI No. 1242), 18.9% (ABI No. 1262), and 0% (SBI) autoclave survivors. Because the time needed to reach 134 degrees C (preconditioning time) increased as the day progressed, and varied from day to day, correlation between individual incremental heat exposure times and the number of surviving BI units was not possible. Standardized test conditions are necessary for a true comparison of BIs.

Biological Assay↗
PubMed1999

Performance and nutrient digestibility by dairy cows treated with bovine somatotropin and fed diets with steam-flaked sorghum or steam-rolled corn during early lactation.

This study compared effects of exogenous bovine somatotropin (bST) on the performance of early lactation cows fed diets differing in ruminally degradable starch. Thirty-two Holstein cows (24 multiparous) in early lactation (5 d in milk) were divided into four groups and fed diets containing 39% grain as steam-flaked sorghum or steam-rolled corn with or without exogenous bST for 90 d. Grain processing did not affect dry matter intake as a percentage of body weight or yields of milk, but steam-rolled corn improved efficiency of feed utilization during the first 45 d of the study. Cows receiving bST had lower dry matter intake during the first 45 d of treatment. Milk yield and efficiency of feed utilization were increased by bST treatment, and milk yield response was greater during the first half than during the second half of the study. Milk composition and yield of milk components did not differ among treatments. Flaked sorghum increased in vitro starch hydrolysis and digestibilities of dry matter, organic matter, and starch, but neither method of grain processing nor bST affected digestibilities of crude protein, acid detergent fiber, or neutral detergent fiber. Grain type did not affect milk yield, and responses to bST were lower from 7 to 13 wk than from 1 to 6 wk prepartum.

Animal Nutritional Physiological Phenomena↗
PubMedDate not supplied

[Use of steam-oxygen tents with a universal steam generator and automatic control system in the treatment of acute stenosing laryngotracheitis in children].

To treat acute stenosing laryngotracheitis in acute respiratory viral infection in children an original method has been developed and used for 2 years in a special hospital department. The method implies treatment of children in steam-and-oxygen tents with a universal steam-moistening generator and automatic control system. A controlled study of 50 children with acute laryngeal stenosis degree I-III confirmed high efficacy of this method permitting improvement of blood oxygenation, gas composition, acid-base condition, reduction of acidosis, prevention of exicosis and brain edema. Warm humid atmosphere promoted better discharge of the secretion and better functioning of the ciliated epithelium. Combined treatment incorporating the tents in acute laryngeal stenoses reduced lethality in severe cases, number of intubations and tracheostomies, of complications resultant from parenteral administration of the drugs.

Acute Disease↗