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Based on a doctoral dissertation, this paper describes a study of why displays of books increase use. Two hypotheses were tested using standard pretest-posttest experimental designs at two small Illinois public libraries. Increased accessibility and visibility were found to be causes, while narrowing the browser's choice was not. (Author/EM)

The development of a nearly defect-free reticle blank is an important challenge facing extreme ultraviolet lithography (EUVL). The core element of an EUVL reticle blank is the reflective Mo/Si multilayer film, and deposition of Mo/Si on very small substrate defects can result in critical Mo/Si phase defects. In this article we present a method for repairing Mo/Si multilayer film phase defects in EUVL reticle blanks. An electron beam is used to deposit energy in the immediate vicinity of the defect, producing a small local contraction of the layer thicknesses due to silicide formation at the Mo/Si interfaces. We show in simulations that this contraction can significantly reduce the original structural deformation. We also present experimental results showing that it is possible to use an electron beam to controllably produce depressions in Mo/Si with nanometer-scale depths, and that this can be achieved without significantly impairing the reflective properties of the Mo/Si multilayer films. © 2002 American Institute of Physics. [ABSTRACT FROM AUTHOR]

Although beta-amyloid (Abeta) plaques are a primary diagnostic criterion for Alzheimer's disease, this pathology is commonly observed in the brains of non-demented older individuals. To explore the importance of this pathology in the absence of dementia, we compared levels of amyloid deposition (via 'Pittsburgh Compound-B' (PIB) positron emission tomography (PET) imaging) to hippocampus volume (HV) and episodic memory (EM) in three groups: (i) normal controls (NC) from the Berkeley Aging Cohort (BAC NC, n = 20); (ii) normal controls (NC) from the Alzheimer's disease neuroimaging initiative (ADNI NC, n = 17); and (iii) PIB+ mild cognitive impairment subjects from the ADNI (ADNI PIB+ MCI, n = 39). Age, gender and education were controlled for in each statistical model, and HV was adjusted for intracranial volume (aHV). In BAC NC, elevated PIB uptake was significantly associated with smaller aHV (P = 0.0016) and worse EM (P = 0.0086). Within ADNI NC, elevated PIB uptake was significantly associated with smaller aHV (P = 0.047) but not EM (P = 0.60); within ADNI PIB+ MCI, elevated PIB uptake was significantly associated with both smaller aHV (P = 0.00070) and worse EM (P = 0.046). To further understand these relationships, a recursive regression procedure was conducted within all ADNI NC and PIB+ MCI subjects (n = 56) to test the hypothesis that HV mediates the relationship between Abeta and EM. Significant correlations were found between PIB index and EM (P = 0.0044), PIB index and aHV (P < 0.0001), as well as between aHV and EM (P < 0.0001). When both aHV and PIB were included in the same model to predict EM, aHV remained significant (P = 0.0015) whereas PIB index was no longer significantly associated with EM (P = 0.50). These results are consistent with a model in which Abeta deposition, hippocampal atrophy, and EM occur sequentially in elderly subjects, with Abeta deposition as the primary event in this cascade. This pattern suggests that declining EM in older individuals may be caused by Abeta-induced hippocampus atrophy. [ABSTRACT FROM AUTHOR]

The chronic mild stress (CMS) procedure was developed in rodents to target anhedonia, the core symptom of depressive melancholia. Stress exposure has been shown to induce a variety of physiological, biochemical and behavioral alterations associated with depression, although its anhedonic consequences as indexed by either sucrose intake and preference or thresholds for brain stimulation reward are less reliably observed. In the present study, we assessed the effects of six weeks of CMS on the latter measure in two strains of male and female rats subsequently challenged with an acute psychophysical stressor, forced swimming; their behavior in the swimming cylinder was evaluated on two consecutive days. While brain stimulation reward thresholds and response rates were unchanged by CMS exposure, significant differences in forced swim behaviors were observed between male control and CMS groups. In particular, male Long Evans rats with a history of CMS showed the largest decrease in the duration of active behaviors on the second test day, a pattern less evident in the Sprague-Dawley strain of rats, or in any of the female groups. The results suggest that the effects of depressogenic manipulations are strain and gender dependent, with male Long Evans rats most susceptible, as demonstrated by the selective reduction of struggling behaviors. Inclusion of multiple measures, including the forced swim test, would provide a better understanding of the psychopathological profile engendered by chronic exposure to mild stressors and its genetic specificity. [ABSTRACT FROM AUTHOR]

Captopril (12.5-25 mg b.d.) was compared with placebo in a double-blind, cross-over study in elderly, hypertensive subjects. Sixteen patients, aged between 65 and 80 years, were studied. The mean baseline blood pressure off treatment was 204.7 +/- 24.5/111.8 +/- 11.1 mmHg. In the 14 patients who completed the study, captopril significantly reduced the systolic and diastolic pressures compared with baseline (P less than 0.001) and compared with placebo (P less than 0.01). The fall in blood pressures was significantly greater at 4 weeks than at 2 weeks (P less than 0.001). No significant change in blood pressure was noted from baseline whilst on placebo. No significant serious side-effects were encountered during the study. We conclude that captopril would appear to be an effective antihypertensive agent which can be safely used in the elderly. [ABSTRACT FROM AUTHOR]

Twenty-three patients of greater than 70 years of age, with proven urinary tract infections were treated with 200 mg of enoxacin twice daily. Serial blood samples were taken on day 1 and peak and trough levels on days 3 and 5. Enoxacin and oxo-enoxacin plasma levels were measured. The mean plasma half-lives of enoxacin and the oxo-metabolite were 6.1 h and 6.7 h respectively. The 2 h plasma level of enoxacin increased from a mean of 1.5 mg/l on day 1 to 2.65 mg/l on day 3 and 2.80 mg/l on day 5. No significant accumulation of the oxo-metabolite (as judged by the 2 h level) occurred. No alteration in enoxacin dosing in the elderly compared with that in younger patients is suggested. Eighty-five per cent of the patients were cured of their infection and no significant adverse advents were noted. [ABSTRACT FROM AUTHOR]

Primary care physicians play an increasingly important role in the care of persons with HIV/AIDS due to the rising number and changing geographic distribution of persons infected with HIV/AIDS. The study explored the relationship between barriers to health services and the experience and willingness of primary care physicians to care for persons with HIV/AIDS. The study was based on a random survey of primary care physicians in South Carolina. The results indicate that although primary care physicians' willingness to treat persons with HIV/AIDS is significantly associated with many self-reported barriers (i.e., financial, structural, knowledge, and attitudinal), their HIV/AID care experience was most significantly correlated with self-reported knowledge that overrides financial and structural barriers. The results emphasize the importance of programs and policy initiatives aimed at enhancing the primary care physicians' knowledge level and improving their attitudes related to HIV/AIDS. [ABSTRACT FROM AUTHOR]