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61.
Separation of fiber from distillers dried grains with solubles (DDGS) provides two valuable coproducts: 1) enhanced DDGS with reduced fiber, increased fat and increased protein contents and 2) fiber. Recently, the elusieve process, a combination of sieving and elutriation was found to be effective in separating fiber from two commercial samples of DDGS (DDGS‐1 and DDGS‐2). Separation of fiber decreased the quantity of DDGS, but increased the value of DDGS by increasing protein content and produced a new coproduct with higher fiber content. Economic analysis was conducted to determine the payback period, net present value (NPV), and internal rate of return (IRR) of the elusieve process. The dependence of animal foodstuff prices on their protein content was determined. Equipment prices were obtained from industrial manufacturers. Relative to crude protein content of original DDGS, crude protein content of enhanced DDGS was higher by 8.0% for DDGS‐1 and by 6.3% for DDGS‐2. For a dry‐grind plant processing corn at the rate of 2,030 metric tonnes/day (80,000 bushels/day), increase in revenue due to the elusieve process would be $0.4 to 0.7M/year. Total capital investment for the elusieve process would be $1.4M and operating cost would be $0.1M/year. Payback period was estimated to be 2.5–4.6 years, NPV was $1.2–3.4M, and IRR was 20.5–39.5%.  相似文献   
62.
63.
本文利用模拟土柱试验研究了施用石灰和石膏对第四纪红粘土发育的红壤中元素淋溶过程的影响。结果表明,施用石灰后10cm土层中除Ca^2+以外的阳离子元素的淋失量减少,而SO4^2-和HCO3^-的淋失量增加;施用石膏后10cm土层中所有阳离子元素,特别是AI^3+的淋失量增加。红壤中Ca^2+的淋失以自由态为主,施用石膏后与SO4^2-结合的比例增加,不同处理中30cm土层处铝的淋失以自由态为离,10  相似文献   
64.
Two hypotheses that could explain increases in the biomass and production of lotic periphytic communities in acidified habitats were tested: 1) a greater bioavailability of P due to its greater release from sediments at low pH, and 2) utilization of S from the H2SO4 addition. The experiments were performed in semi-natural conditions by submitting the periphyton to either continuous or episodic acidification. The uptake of P and S by periphyton were determined at different times during the treatments. The increases in P and S uptake, in acidified habitats, are compatible with both hypotheses and could account for the increase in periphytic biomass and production.  相似文献   
65.
1. Fear‐related behaviour was measured in individually‐housed Japanese quail which had received either untreated drinking water (UDW) or a vitamin C solution (ascorbyl‐2‐polyphosphate, APP, 1 g L‐ascorbic acid/1) for 1 or 4 d. Behavioural tests were carried out at 24 or 27 d of age. Water consumption was measured daily and plasma ascorbic acid (AA) content was assayed after differential treatment for 1 or 4 d.

2. The quail in the APP treatment groups drank significantly more than did those receiving untreated drinking water.

3. Supplementation with APP raised plasma AA concentrations substantially above those found in UDW quail. The lower AA concentrations found after APP treatment for 4 d rather than one may have reflected either inter‐assay variation or limited intestinal absorption following excess ingestion.

4. Quail treated with APP showed less home‐cage avoidance of a novel object and shorter tonic immobility fear reactions than did the UDW birds. The UDW quail showed remarkably similar avoidance and TI scores on test days 1 and 4. Conversely, continued treatment with APP further reduced avoidance scores but, although TI durations fell slightly with continued treatment there were no significant day effects.

5. It was concluded that APP supplementation can reduce underlying fearfulness but that it may not be necessary to continue treatment for longer than 24 h immediately prior to a known frightening event.  相似文献   

66.
A consecutive series of cases of dogs and cats with locked jaw syndrome (inability to open or close the mouth) are reported in this study. Dogs were significantly overrepresented (84.0%) and adult dogs were more frequently affected (81.0%). Temporomandibular joint ankylosis due to fracture was the most common cause (54.0%) of locked jaw syndrome. Additional potential causes of locked jaw syndrome are masticatory muscle myositis, neoplasia, trigeminal nerve paralysis and central neurological lesions, temporomandibular joint luxation and dysplasia, osteoarthritis, retrobulbar abscess, tetanus, and severe ear disease. Treatment of locked jaw is directed towards the primary cause. It is important to treat the tonic spasm in order to minimize periarticular fibrosis. Surgical intervention is recommended for temporomandibular joint ankylosis. Masticatory muscle myositis treatment is initiated by gradually opening the mouth, with medical treatment based on immunosuppressive therapy. Fracture and masticatory muscle myositis are associated with a relatively good prognosis in regard to short-term outcome as compared to animals with central neurologic lesions or osteosarcoma which have a poor prognosis.  相似文献   
67.
ABSTRACT

Thirty-one strawberry genotypes were evaluated for supporting the reproductive success of the strawberry aphid (Chaetosiphon fragaefolii), a vector of several strawberry viruses. A pure colony of C. fragaefolii was initiated from eggs collected from field strawberry leaves in Fall 2013. In Spring 2014 greenhouse-grown strawberry plants with four to five leaves were placed in screened cages (16 genotypes/cage) and five aphids were placed on each plant. After 30–32 days, the number of aphids in each of four developmental stages was counted on each plant. Total aphid numbers/plant ranged from a mean of 33 on Fragaria chiloensis CFRA 48 (PI 551459) to 279 on F. × ananassa ‘AAC Lila’. Cultivars with relatively low numbers of aphids included ‘Bounty’ (106 aphids), ‘Mira’ (114 aphids), and ‘Annapolis’ (115 aphids). This experiment, part of a larger project on aphids and virus diseases associated with the cultivated strawberry, will inform decisions in the strawberry breeding program.  相似文献   
68.
Maize prolamin (zein), together with starch, hydroxypropyl methylcellulose, sugar, salt, yeast and water can form wheat-like cohesive, extensible, viscoelastic dough when mixed above room temperature (e.g. 40 °C). This dough is capable of holding gas. However, it is excessively extensible, and when used for hearth-type rolls, it tends to become flat. Bench-scale defatting of zein with chloroform at room temperature significantly (P < 0.05) improved specific volume (4.5 ml/g vs. 3.3 ml/g) and shape of the rolls (width-to-height 2.0 vs. 3.9). The total lipid content determined by accelerated solvent extraction (100 °C, 69 bar, chloroform), however, only decreased from 8.0 to 6.6% due to this bench-scale defatting. Staining experiments with Naphthol Blue Black suggested that bench-scale defatting removed surface lipids from the zein particles, and thus facilitated their aggregation. Aggregation experiments with zein and water at 40 °C, and laser scanning confocal microscopy with zein-starch dough confirmed that zein particles aggregated more easily when surface-defatted. Dynamic oscillatory temperature sweeps demonstrated that surface-defatting lowered the temperature at which protein cross-linking occurred by 2 °C. This research can help to produce superior gluten-free bread and could also possibly contribute to the better understanding of wheat dough.  相似文献   
69.
Dietary protein and energy utilization were compared in three Pangasiid species of high economical interest for fish farming in South‐East Asia. Feeding experiments were performed during 4 weeks on Pangasius bocourti, P. djambal and P. hypophthalmus fingerlings, 6.68, 7.69 and 6.41 g mean mass, respectively. A high‐protein diet containing mostly fishmeal was designed to provide proteins without energy limitation. Growth response, variation in body composition and nutrient utilization were compared for fish receiving variable amounts of diet corresponding to increasing protein supply, 0, 5, 15, 25, 35 and 45 g kg?1 day?1. The highest specific growth rate was observed for P. bocourti (6.0% day?1), followed by P. djambal (5.6) and P. hypothalamus (4.1). Pangasius djambal exhibited the highest protein deposition rate, whereas P. bocourti was characterized by a high fat deposition rate even with a low feeding rate. Lower performance was obtained with P. hypophthalmus.  相似文献   
70.
This research focuses on the overall extraction process of alkylresorcinols (ARs) from uncooked grains and baked products that have been processed with wheat, corn, rice, and white flour. Previously established extraction methods developed by Ross and colleagues, as well as a semiautomated method involving accelerated solvent extraction (ASE), were applied to extract ARs within freshly ground samples. For extraction of alkylresorcinols, nonpolar solvents such as ethyl acetate have been recommended for the extraction of uncooked foods, and polar solvents such as 1-propanol:water (3:1 v/v) have been recommended for the extraction of baked foods that contain rye, wheat, or other starch-rich grains. A comparison of AR extraction methods has been investigated with the application of gas chromatography and a flame ionization detector (GC-FID) to quantify the AR content. The goal of this research was to compare the rapid accelerated solvent extraction of the alkylresorcinols (ASE-AR) method to the previous manual AR extraction methods. Results for this study as well as the investigation of the overall efficiency of ASE-AR extraction with the use of a spiking study indicated that it can be comparable to current extraction methods but with less time required. Furthermore, the extraction time for ASE (approximately 40 min) is much more convenient and less tedious and time-consuming than previously established methods, which range from 5 h for processed foods to 24 h for raw grains.  相似文献   
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