29 research outputs found
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Cover crops and biochemical functional diversity in relation to nitrogen availability in soil
Nitrogen availability in agricultural soils from fertilizer, plant residue inputs, and soil organic matter has important implications beyond crop yield. Legume winter cover crops and one fourth the recommended N rate on sweet corn resulted in yields equivalent to those at the recommended rate in the Willamette Valley of western Oregon. Cereal rye winter crops absorbed an average of 40 kg N/ha that otherwise would have been leached, but did not effectively replace fertilizer N. Cereal rye as a cover crop therefore shows an ability to immobilize N from fertilizer. This was further confirmed in an experiment with "N labeled urea where results showed that N derived from fertilizer in sweet corn or cereal rye plant residue was less available for crop uptake and loss from the system than inorganic N or N directly immobilized from fertilizer. Losses of N from fertilizer ranged from 40 to 73% of that which was in the soil over winter. Mineralization of organic matter N is an important process in N availability, especially when cover crops are used to replace fertilizer. Finding a general indicator or predictor of N mineralization in soils would help in reducing fertilizer N costs and leaching of inorganic N that is applied in excess of crop needs. In a screening of 17 biological and chemical properties of 19 differently managed soils from around the state of Oregon, a model using total soil N and β-glucosidase activity provided the best model of mineralized N uptake by ryegrass. Biological activity is primarily responsible for the transformations that result in N availability in soils. Management of soils directly impacts soil biology, and results from multivariate analyses of biological and chemical parameters in differently managed soils showed that disturbance creates an overriding common biochemical state in soils. Beyond disturbance, vegetation and the nature of organic inputs also impart recognizable multivariate patterns in soils managed differently. These results suggest that indicators independent of soil type may be used to discern effects of management on agricultural soils
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INEXPENSIVE, OFF THE SHELF HYBRID MICROWAVE SYSTEM
A hybrid-heating microwave oven provides the energy to heat small 10-gram samples of spent metal tritide storage bed material to release tenaciously held decay product {sup 3}He. Complete mass balance procedures require direct measurement of added or produced gases on a tritide bed, and over 1100 C is necessary to release deep trapped {sup 3}He. The decomposition of non-radioactive CaCO{sub 3} and the quantitative measurement of CO{sub 2} within 3% of stoichiometry demonstrate the capabilities of the apparatus to capture generated (released) gases
Renal artery stenosis-when to screen, what to stent?
Renal artery stensosis (RAS) continues to be a problem for clinicians, with no clear consensus on how to investigate and assess the clinical significance of stenotic lesions and manage the findings. RAS caused by fibromuscular dysplasia is probably commoner than previously appreciated, should be actively looked for in younger hypertensive patients and can be managed successfully with angioplasty. Atheromatous RAS is associated with increased incidence of cardiovascular events and increased cardiovascular mortality, and is likely to be seen with increasing frequency. Evidence from large clinical trials has led clinicians away from recommending interventional revascularisation towards aggressive medical management. There is now interest in looking more closely at patient selection for intervention, with focus on intervening only in patients with the highest-risk presentations such as flash pulmonary oedema, rapidly declining renal function and severe resistant hypertension. The potential benefits in terms of improving hard cardiovascular outcomes may outweigh the risks of intervention in this group, and further research is needed
Neurobiology of rodent self-grooming and its value for translational neuroscience
Self-grooming is a complex innate behaviour with an evolutionarily conserved sequencing pattern and is one of the most frequently performed behavioural activities in rodents. In this Review, we discuss the neurobiology of rodent self-grooming, and we highlight studies of rodent models of neuropsychiatric disorders-including models of autism spectrum disorder and obsessive compulsive disorder-that have assessed self-grooming phenotypes. We suggest that rodent self-grooming may be a useful measure of repetitive behaviour in such models, and therefore of value to translational psychiatry. Assessment of rodent self-grooming may also be useful for understanding the neural circuits that are involved in complex sequential patterns of action.National Institutes of Health (U.S.) (Grant NS025529)National Institutes of Health (U.S.) (Grant HD028341)National Institutes of Health (U.S.) (Grant MH060379
Buckle.
Patent for a new and improved buckle. This design utilizes two separate tongues that run freely along a middle bar, which lengthens the life of the strap by distributing pressure and allowing for broken out, frayed, or otherwise worn holes to be circumvented for new ones
Vitamin D receptor expression in the embryonic rat brain
We are interested in determining whether low maternal vitamin D-3 affects brain development in utero. Whilst the vitamin D receptor (VDR) has been identified in embryonic rat brains, the timing and magnitude of its expression across the brain remains unclear. In this study we have quantitated VDR expression during development as well correlated the timing of its appearance with two vital developmental events, apoptosis and mitosis. Brains from embryonic rats (embryonic days 15-23) were examined. We show that the well-described increase in apoptotic cells and decrease in mitotic cells during development correlates with the appearance of the VDR in brain tissue. Given that vitamin D-3 regulates mitosis and apoptosis in non-neuronal tissue we speculate that the timing of VDR expression in embryonic brain may directly or indirectly mediate features of neuronal apoptosis and mitosis
Differential blood count in periodontal diseases. A preliminary report on blood obtained from the gingival tissues and the finger tip
DSM-Ill Diagnoses and Offenses in Committed Female Juvenile Delinquents
The relationship between juvenile delinquency and psychiatric disorders remains poorly understood. However, it is becoming more apparent that the spectrum of psychiatric illness present in juvenile delinquents is broader than once believed. Fifteen female juvenile delinquents committed to a residential treatment program were assessed for DSM-Ill diagnoses, using a structured diagnostic interview, the Diagnostic Interview for Children and Adolescents (DICA). A search of the literature revealed no other reports using the DICA in female juvenile delinquents. A broad spectrum of current and past diagnoses was discovered, including conduct disorder (10O0/0), substance abuse/dependence (87%), major depression (67%), and anxiety disorders (47%). The average number of lifetime diagnoses per subject was 4.7; current diagnoses averaged 3.4 per subject. Additionally, criminal and status offense records were obtained for each subject. No significant relationship was noted between diagnoses and categories of offense. These results add further evidence for the presence of frequent and severe psychiatric disturbances in this population, and the need for increased clinical and research efforts by the psychiatric community. The boundaries between psychiatric illness and the terms conduct disorder and delinquency remain poorly understood. Lewis er ul.' noted that the diagnosis of conduct disorder encompasses a multiplicity of signs and symptoms characteristic of other psychiatric disorders, and that often the difference between psychiatrically hospitalized adolescents and found that the psychopathology in a sample of delinquent and nondelinquent psychiatrically hospitalized adolescent boys was similarly severe. and that at one time the majority of the delinquents had been regarded as severely psychiatrically disturbed. These two reports point out the presence of multiple and serious psychiatric symptoms in youth with antisocial behavior. yet the investigators' reliance on past records to generate their data bases and the lack of a standard diagnostic classification system precluded the identification of valid and reliable psychiatri