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31.
Two research studies were conducted to evaluate weed control in potato with dimethenamid and dimethenamid-p. No significant injury was observed from most applications of dimethenamid prior to potato emergence, but injury was 20% to 38% with dimethenamid when emerging potatoes were covered slightly by soil during “drag-off” and rain occurred within 24 h. Common lambsquarters (Chenopodium album L.) and common ragweed (Ambrosia artemisiifolia L.) control with dimethenamid preemergence (PRE) did not exceed 68%. Dimethenamid-p plus metribuzin or dimethenamid-p followed by (fb) rimsulfuron postemergence (POST) controlled common lambsquarters 95% to 96% and common ragweed 71% to 92%. Annual grass control was greater with S-metolachlor alone than with dimethenamid isomers alone. Broadleaf and grass control was similar with dimethenamid and dimethenamid-p.  相似文献   
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OBJECTIVE: To determine the effects of treatment with and without adjuvant radiation therapy on recurrence of ocular and adnexal squamous cell carcinoma (SCC) at specific anatomic locations in horses. DESIGN: Retrospective study. ANIMALS: 91 horses. PROCEDURES: Medical records of horses with histologically confirmed ocular and adnexal SCC evaluated from 1985 to 2002 were reviewed. Sex, breed, age, type of treatment, location, and recurrence of SCC were recorded. Two treatment groups determined by recurrence of SCCs treated with and without adjuvant radiation therapy were established. RESULTS: The anatomic site with the highest recurrence rate was the limbus (junction of the cornea and sclera) or bulbar conjunctiva (477%), independent of treatment group. There was a significant difference in recurrence rates of ocular and adnexal SCCs between the 2 treatment groups, independent of anatomic location. Recurrence rates of SCCs treated with and without adjuvant radiation therapy were 11.9% and 44.1%, respectively. Recurrence rates for SCCs of the eyelid, limbus or bulbar conjunctiva, and cornea treated with adjuvant radiation therapy were significantly different from those for SCCs treated without adjuvant radiation therapy. The most frequently represented anatomic site for ocular and adnexal SCCs was the eyelid (28.7%). Coat color, breed, and the interaction of age and breed had a significant effect on tumor recurrence regardless of treatment type and anatomic location. CONCLUSIONS AND CLINICAL RELEVANCE: Results indicated that ocular and adnexal SCCs treated with adjuvant radiation therapy had a significantly lower recurrence rate, compared with SCCs treated without adjuvant radiation therapy, independent of anatomic location.  相似文献   
33.
Arkansas Discovery Farms (ADFs) are private farms that collaborate with on-farm research, verification, and demonstration of farming's impact on the environment. We have nine ADFs representing livestock (broiler poultry and pasture grazed beef and sheep) and row crop agriculture (corn, cotton, rice, soybean, and wheat), where we collect water use and water quality data as a function of conservation management, using autosamplers equipped with edge-of-field H-flumes or weir flow structures, which measure and collect surface runoff. On the poultry farms, we are monitoring nutrient and sediment runoff originating immediately near poultry houses due to concerns with spillage of litter during bird removal and house clean out, as well as dust from tunnel ventilation. On a nearby farm we are assessing the impact of rotational grazing on water quality, soil organic matter, and soil health metrics. On the row crop farms we are assessing the impacts of conservation tillage and cover crops on soybean–corn rotations and cotton on nutrient and sediment runoff and the benefits of water harvesting and reuse of water conservation and quality. The information in this paper while preliminary, demonstrates how a state-wide on-farm demonstration program operates. Elevated nutrient and sediment runoff from around poultry production areas are decreased three-fold by directing runoff into ponds or through grassed waterways. While conservation tillage and cover crops do decrease nutrient and sediment runoff, no significant difference between conventional and conservation operations is yet to be realized. Importantly, ADF empowers farmers to proactively address environmental concerns. This paper discusses the development, guidance, principals, and goals of ADF and contrasts this with other farm monitoring projects, where the sources of nutrient impairment are the subject of ongoing litigation. Monitoring in divisive and transparent situations presents unique challenges with data ownership and release of findings, which can hinder productive outcomes of such monitoring.  相似文献   
34.
Ruett  Marius  Dalhaus  Tobias  Whitney  Cory  Luedeling  Eike 《Precision Agriculture》2022,23(5):1775-1800
Precision Agriculture - Many farmers hesitate to adopt new management strategies with actual or perceived risks and uncertainties. Especially in ornamental plant production, farmers often stick to...  相似文献   
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There are a number of correlations between the pathophysiology and behavioral expression of early Alzheimer disease in humans and age-related cognitive dysfunction in dogs and cats. Changes in social interaction and the reduced ability to cope with everyday situations are difficulties experienced in human, canine, and feline age-related cognitive decline. Anxiety, distress, and confusion commonly precede diagnosis. Information obtained from family members, carers, or owners may be key to identifying early behavioral markers and allowing early management or treatment.Environment may predispose to or protect from cognitive decline over time. Neuroinflammation associated with air pollution or excessive noise can lead to oxidative damage within the cerebrum and development of β-amyloid plaques. Targeted programs promoting mental exercise may be used to delay progression once clinical signs have been presented.Pharmacological interventions in humans have focused mainly on augmenting neuronal efficacy by using agents to increase the chemical communication, whereas in veterinary medicine cerebral vasodilators are commonly used. Preclinical and mildly impaired patients have limited options in human medicine, whereas there is a trend in veterinary medicine to offer targeted nutritional supplements that include antioxidants, L-carnitine, or omega-3 fatty acids.Comparing treatment options in species provides opportunities to identify new methods of controlling age-related cognitive decline.  相似文献   
37.
ABSTRACT

The growth of global aquaculture has put intense pressure on sources of fish oil and fishmeal for aquafeeds. The nutraceuticals industry has added further pressure on fish oils with high Omega-3 fatty acids. GM soybeans could provide substitutes in high Omega-3 soybean oil (STA oil), as well as soy protein concentrate (SPC). This article examines the technological and economic feasibility of substituting STA oil for one-half the fish oil in the diet of Seriola rivoliana, a species often destined for sushi markets. Previous studies have shown that the substitution results in no change in flesh quality or consumer acceptance. We find that the two feed technologies result in essentially identical growth pattern and feed consumption. Economic feasibility depends upon the price of STA oil being lower than the price of fish oil. Based on our market analysis, we estimate that STA oil will enter the market at a price about two-thirds of the fish oil price. The estimated cost savings at these prices are small, a 2.8% reduction in feed costs and 0.9% reduction in total costs. However, the potential global market for STA oil could be as much as 252 thousand metric tons annually, which would require soybean production equivalent to that from 1.63% of current U.S. soybean area.  相似文献   
38.
Baculoviruses are natural pathogens of insects which have been used as biopesticides. In contrast to many chemical agents, baculoviruses affect only a limited number of insects and so can be used to target particular insect species. Unfortunately, unless the host receives a very high virus dose, the insect continues to feed and causes damage to crops, because the virus takes several days to kill it. This lag is unacceptable in the protection of many crops, especially where cosmetic damage seriously reduces the value of a crop (e.g. fruit). Strategies have been devised recently to circumvent this problem. The baculovirus genome has been modified, using genetic engineering techniques, to incorporate foreign genes encoding insect-specific toxins, or hormones or enzymes. Expression of some of these genes in the virus-infected host insect has been shown to reduce both the feeding damage to crop plants and the time taken to kill the insect pest. The current status of this developing field is described, together with an assessment of the possible risks involved in using such genetically modified agents in the environment.  相似文献   
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40.
Copper profiles in the sediments of a mining-impacted lake   总被引:1,自引:0,他引:1  

Purpose  

The sediments of Torch Lake, located in Houghton County, MI, USA, have been impacted by copper mining activity. Remediation of the site has focused on immobilizing shoreline tailing deposits. However, a large amount of copper remains in the mining-sourced sediment, and high copper concentrations persist in surface sediments. This study analyzes sediment core and sediment trap data to determine the source of copper in the surface sediments.  相似文献   
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