In vitro effects of urease inhibitors on rate of urea hydrolysis in soils

We studied the effect of urease inhibitors on the urea hydrolysis in some Sundanese soils belonging to the orders of Vertisol and Entisol. The hydrolysis showed a lag period of about 3 days and its rate (Y) per unit time (t) could be described by a two constants exponential equation of the general form Y = K₁t^K ₂. Statistical analysis showed that the intercept K₁ (rate of urea hydrolysis) was significantly affected by soil type rather than treatment. It seems that K₁ is associated with the soils' initial urease activity as it closely correlates with the Michaelis constant (km).The gradient, K₂, being significantly affected by soil type as well as treatment is probably associated with the induced urease activity with time and it, therefore, varied with variations in soils and treatments. Of the so-called urease inhibitors used in this study Ca(OH)₂, p-benzoquinone (PBQ) and orthophosphoric acid (OP) only PBQ reduced urea hydrolysis while the other chemicals have effects possibly related to modifying the soil pH. Inhibitor treated soils had substantial amounts of unacounted for N which was believed to be present, presumably, in the form of carbamate.Contribution from the Department of Biochemistry and Soil Science, Faculty of Agriculture, Shambat, Sudan.     

一种新的SDH开销处理方法

文章提出了一种较为实用的SDH系统方案，并在系统中采用了一种新型的、便于系统升级的开销处理方法，该系统已通过了电路实现和硬件的测试，     

Political correctness and academic principles: a reply to Simpson

The author discusses Christopher Simpson's (1996) article, 'Elisabeth Noelle-Neumann's 'Spiral of Silence' and the Historical Context of Communication Theory.' He questions the relevance of biographical data for the evaluation of scientific theories and methods, and analyzes the rhetorical structure of Simpson's arguments. He concludes that Simpson's claims about the influence of Noelle's biography on her scholarly work are not grounded in evidence.     

Narrative analysis of sexual etiquette in teenage magazines

Expanding on existing research on women's magazines, this essay examines the sexual etiquette developed in advice columns in magazines popular among teenage women. Over a span of 20 years, the advice has changed very little. Serving the rhetorical function of field guides and training manuals, teen magazines limit women's sociality and sexuality within narrowly defined heterosexual norms and practices. The rhetoric of sexual etiquette encourages young women to be sex objects and teachers of interpersonal communication rather than lovers, friends, and partners. Young women are being taught to subordinate self for others and to be contained.     

Progressive spastic paraparesis and adrenal insufficiency

A 10-year-old boy with progressive paraparesis, personality change, and seizures had laboratory evidence of adrenal insufficiency. Pathologic study showed cerebral edema, but no loss of myelin. Notable pathologic changes were limited to the spinal cord, where the corticospinal and spinocerebellar tracts were demyelinated. Lipid analysis of the brain was normal apart from the finding that galactocerebroside contained a higher proportion than normal of alpha-hydroxy fatty acids. We suggest that this case represents a distinct disease, differing importantly from adrenoleukodystrophy. The underlying defect appears to be in the early enzymatic pathway before cholesterol synthesis, although it is also possible that the defect is at the cell membrane.     

Transillumination of the skull in premature infants

Transillumination of the skull in infants is a simple technique which can be used to detect several major abnormalities of the central nervous system. The usefulness of transillumination has been limited, however, by the lack of standard techniques for its performance and by the absence of normal values, especially in premature infants. In healthy premature infants, there is a progressive increase in transillumination with increasing gestational age over three sites--the anterior fontanelle, the frontotemporal fossa, and the parieto-occipital eminence.     

Lymphocytic choriomeningitis from pet hamster exposure: a local public health experience

Eleven cases of hamster associated lymphocytic choriomeningitis occurred within a space of four months in Jefferson County, Alabama residents. A single Birmingham breeder was the source of the infected hamsters. Ten cases experienced an illness of one to three weeks duration with grippe-like symptoms being most frequent. Complaints of nine cases suggested meningeal involvement, and one was asymptomatic. All patients recovered uneventfully. Frequent hamster contact had occurred in most cases, although three individuals reported infrequent or room exposure to the animals. The holding of hamsters for observation prior to sale, random testing of all breeders' stock, and the distribution of printed information with each hamster sold are suggested as precautions against future outbreaks of this nature.