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991.
Hydrophilic gums have been shown to improve the shelf‐life stability of frozen doughs during long periods of frozen storage. The objective of this research was to determine the effect of gums on starch and protein characteristics of frozen doughs using electron microscopy and electrophoresis studies. Frozen doughs, supplemented with three levels of gum arabic, carboxy methyl cellulose (CMC), kappa (κ) carrageenan, and locust bean gum, were studied after day 1 and after 4, 8, 12, and 16 weeks of frozen storage. Changes in the ultra structure of the frozen doughs were investigated, as well as the solubilities and composition of dough proteins by SDS‐PAGE. Scanning electron micrographs of doughs evaluated on day 0 (unfrozen) showed starch granules securely embedded in the gluten matrix. However, after 8 and 16 weeks of frozen storage, the frozen control dough without the gum additives clearly showed damage to the gluten network, and the starch granules appeared to be separated from the gluten. Doughs with locust bean gum and gum arabic showed better retention of the gluten network compared with the frozen control evaluated after different periods of storage. The SDS‐soluble protein content increased while residue protein content decreased as the frozen storage time increased. After each frozen storage period, the control dough without the gum additive had the highest amount of SDS‐soluble proteins and the lowest amount of residue proteins when compared with the doughs treated with gums. κ‐Carrageenan and locust bean gum had the lowest amount of SDS‐soluble proteins compared with doughs with CMC and gum arabic. The frozen control had the lowest amount of residue proteins at any particular time of frozen storage. κ‐Carrageenan treated doughs had the highest amount of residue proteins, followed by doughs with locust bean gum. Doughs with gum arabic and CMC had the lowest amount of residue proteins but still higher than the control doughs.  相似文献   
992.
Information is presented on the nature, extent and spatial distribution of waterlogged areas and salt-affected soils, derived through systematic visual interpretation of standard false colour composite (FCC) prints on a 1:100 000 scale generated from the Indian Remote Sensing Satellite (IRS-1B) Linear Imaging Self-scanning Sensor (LISS-I) and Landsat–Thematic Mapper (TM) data for the Nagarjunsagar Right Bank Canal Command Area, Andhra Pradesh. A total of 1710 ha of land in the coastal region has been found to be waterlogged. Salt-affected soils cover an area of 42 800 ha, with saline–sodic soils covering 28 480 ha emerging as the dominant category. To make optimal use of these lands and to prevent further degradation both preventive and ameliorative measures have been advocated. © 1998 John Wiley & Sons, Ltd.  相似文献   
993.
A green atmosphere and interaction with nature (plants and flowers) can considerably improve the human senses and sanity by decreasing the stress associated with anxiety, depression, neurotic impairment, and other psychologic symptoms. The current paper reports a therapeutic horticultural study’s findings regarding the effect of indoor foliage plants and flower arrangements on health prospects of surgical patients. Two surgical wards, ward A (with foliage plants and arranged flowers) and ward B (without foliage plants and flowers), were selected for the study. A total of 270 patients were randomly assigned to either ward to give 135 patients in each. Patients admitted to ward A had significantly more optimistic and promising health improvements than those in ward B. Provision of foliage plants and flower arrangements to the patients in ward A resulted in shorter postoperative stays, lower intake of analgesics, lower pain intensity, less stress fatigue, and improved vital signs (blood pressure, heart rate, respiration rate, body temperature) as compared to patients in ward B. Moreover, analyses showed that patients in ward A had a stronger psychologic frame of mind regarding their recovery from surgery and had more positive emotions and feelings regarding their stay in the hospital. They also felt that the ward atmosphere was more calming, pleasant, and satisfactory. Additionally, small group discussions and focal interviews with ward doctors and nurses confirmed the findings of the questionnaire that foliage plants & flower arrangements create a cherished environment in the ward, reduce patients’ stress, improve medical and psychologic status of patients, and also conveye positive messages of the hospital. These findings confirm the therapeutic value of horticultural activities, particularly in surgical patients in a stressed hospital setting.  相似文献   
994.
In the present study, juvenile (live body weight, 54.3 ± 8.2 g), preadult (live body weight, 822.5 ± 33.9 g), and adult (live body weight, 1,562.8 ± 41.8 g) pacu, Piaractus mesopotamicus, were used to estimate their dietary essential amino acid (EAA) requirements using the whole-body amino acid (AA) pattern. The results showed that whole-body moisture, crude protein, total lipid, and ash contents expressed on a wet weight basis (%) were significantly different among the studied growth phases. No significant differences were observed in the dietary EAA requirements estimated for the three growth phases of pacu. These dietary EAA requirements were found to be different than those previously estimated for the same fish through its muscle AA pattern. Based on whole-body EAA to total EAA ratios {A/E ratios; [(each EAA/total EAA) × 1,000]}, EAA requirements were estimated to be histidine (0.42%), arginine (1.36%), threonine (0.82%), valine (0.90%), methionine (0.45%), isoleucine (0.83%), leucine (1.29%), phenylalanine (0.74%), lysine (1.64%), and tryptophan (0.14%) for pacu. These estimated requirements may serve as a reference line in the formulation of practical and experimental diets until dose–response-based optimum EAA requirements are available for pacu.  相似文献   
995.
The dietary folic acid requirement of fingerling Catla catla (3.4 ± 0.17 g; 7.6 ± 0.41 cm) was evaluated by feeding casein–gelatin‐based isonitrogenous (350 g/kg crude protein) and isocaloric (16.72 kJ/g GE) diets containing different concentrations of folic acid (0, 0.2, 0.4, 0.6, 0.8, 1.0, 2.0 mg/kg) to triplicate groups to apparent satiation at 08:00, 12:30 and 17:30 hr for 16 weeks. Absolute weight gain (AWG; 40.07 g/fish), specific growth rate (SGR; 2.25%), feed conversion ratio (FCR; 1.53), protein retention efficiency (PRE; 31.42%) and protein gain (PG; 6.74) improved significantly (p < .05) with increasing folic acid levels up to 0.4 mg/kg diet and then reached a plateau. However, maximum liver folic acid concentration increased up to 0.6 mg/kg diet. Dietary folic acid levels also significantly affected (p < .05) body composition of fish. No significant change (p > .05) in haematological parameters except in fish fed folic acid‐free diet was noted. Antioxidant and immune parameters increased with increasing concentration of dietary folic acid up to 0.4 mg/kg diet. Broken‐line regression analysis of AWG, FCR, PRE, PG, HCT and liver folic acid concentrations of fingerling C. catla against dietary folic acid levels indicated optimum growth, FCR, PRE, PG, HCT and liver folic acid saturation ranging between 0.22 and 0.56 mg/kg diet, respectively.  相似文献   
996.
An 8-week growth trial was conducted to assess the effect of dietary protein on growth, feed utilization, protein retention efficiency, and body composition of young Heteropneustes fossilis (10.02 ± 0.09 g; 9.93 ± 0.07 cm). Isocaloric (4.15 kcal g−1, GE) diets with varying levels of protein (25, 30, 35, 40, 45, and 50% of the diet) were fed near to satiation to triplicate groups of fish. Optimum dietary protein was determined by analyzing live weight gain (LWG%), feed conversion ratio (FCR), protein efficiency ratio (PER), specific growth rate (SGR%), and protein retention efficiency (PRE%) data. Maximum LWG% (167), best FCR (1.42), PER (1.75), SGR (1.76), and PRE (31.7%) were evident in fish fed 40% protein diet (Diet 4). Body protein data also supported the above level. However, second-degree polynomial regression analysis of the above data indicated that inclusion of dietary protein in the range of 40–43% is optimum for the growth of young H. fossilis.  相似文献   
997.
The purpose of the article is to investigate the effects of water-saving irrigation on weed infestation and diversity in paddy fields; a two-year field experiment was conducted in Gaoyou Irrigation District, China. The responses of two irrigation treatments, controlled irrigation (CI) and traditional irrigation (TI), were observed and compared. The irrigation water use, yield, weed density, coverage ratio, height, species richness, density, dominant species, Shannon–Wiener index, and Pielou index were examined to analyze the water productivity, weed infestation, and diversity in paddy fields under the two treatments. The results showed that the water conditions were similar before the late tillering stage, and thereafter the CI fields were alternatively dry and wet with shallow standing water and low soil water content, while the TI fields were mostly continuously flooded by deep standing water and high soil water content. Irrigation water use for CI was 46.8% lower than TI. The CI treatment reduced weed density by 38.0%, decreased coverage ratio by 13.8%, and resulted in a 39.0% increase in weed height. Fewer species were found in CI fields than TI fields. The Shannon–Wiener index decreased by 11.5%, and the Pielou index increased by 3.2%. The changed water regime under CI not only impeded the growth of dominant species but also placed the whole weed community at a relatively stable level with reduced weed density. Meanwhile, aquatic weeds were well controlled; however, semi-aquatic weeds became the dominant species. In general, CI effectively reduced the risk of weed outbreaks, and weed diversity also decreased when it reduced irrigation water use.  相似文献   
998.
Natural antioxidants applied as feed additives can improve not only animals’ health and overall performance but also increase their resistance to environmental stress such as heat stress, bad housing conditions, diseases, etc. Marine organisms, for example seaweeds – red, brown, and green macroalgae contain a plethora of biologically active substances, including phenolic compounds, polysaccharides, pigments, vitamins, micro- and macroelements, and proteins known for their antioxidant activity, which can help in the maintenance of appropriate redox status in animals and show pleiotropic effects for enhancing good health, and productivity. The dysregulated production of free radicals is a marked characteristic of several clinical conditions, and antioxidant machinery plays a pivotal role in scavenging the excessive free radicals, thereby preventing and treating infections in animals. Supplementation of seaweeds to animal diet can boost antioxidant activity, immunity, and the gut environment. Dietary supplementation of seaweeds can also enhance meat quality due to the deposition of marine-derived antioxidant components in muscles. The use of natural antioxidants in the meat industry is a practical approach to minimize or prevent lipid oxidation. However, overconsumption of seaweeds, especially brown macroalgae, should be avoided because of their high iodine content. An important point to consider when including seaweeds in animal feed is their variable composition which depends on the species, habitat, location, harvest time, growing conditions such as nutrient concentration in water, light intensity, temperature, etc. This review highlights the beneficial applications of seaweeds and their extracted compounds, which have antioxidant properties as feed additives and impact animal health and production.  相似文献   
999.
Indian major carp, Cirrhinus mrigala fingerling (3.85 ± 0.50 cm, 0.50 ± 0.02 g) were fed isonitrogenous and isocaloric diets (40% CP, 4.28 kcal g−1, GE) containing casein, gelatin and crystalline amino acids with graded levels of L- methionine (0.50, 0.75, 1.00, 1.25, 1.50 and 2.00 g/ 100 g, dry diet) with 1.00% cystine fixed, to determine its dietary methionine requirement. A feeding trial was conducted in triplicate for six weeks. Diets were fed twice a day at 0800 and 1600 h at 5% of body weight/day. The ration size and feeding regime were worked out prior to the start of the feeding trial. Weight gain (158%) and food conversion ratio (1.45) were significantly (P < 0.05) higher in fish fed diet containing 1.00% methionine with 1.00% cystine fixed. Second degree polynomial regression analysis of the weight gain data indicated the dietary methionine requirement to be 1.20 g/100 g of dry diet, corresponding to 3.00% of dietary protein. Second degree polynomial regression analysis was also employed to determine the relationship between food conversion ratio (FCR) and dietary methionine levels which indicated that the best FCR occurred at approximately 1.20% dietary methionine level. Carcass composition of fish fed diet containing graded levels of methionine varied significantly (P < 0.05) except carcass ash content which showed insignificant (P > 0.05) differences among the dietary methionine levels. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   
1000.
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