Finite-size effects in surface tension: Thermodynamics and the Gaussian interface model

It has been suggested by Kayser that finite-size effects associated with capillary waves might play a significant role in some surface tension measurements; for capillary rise between plates a distance D apart, an effect varying as 1/D and apparently observable in measurements, was proposed. In reconsidering this problem, one must analyze the thermodynamics of finite-size corrections to surface tension. In particular, one sees that capillary rise between plates does not measure the interfacial free energy density but, rather, a derivative of the interfacial free energy with respect to a system dimension. The quantity needed to draw definite conclusions, the finite-size residual free energy, can be calculated within the harmonic or Gaussian capillary wave model in d spatial dimensions with the aid of Poisson summation techniques and should yield the correct leading asymptotic behavior. For d=3 and experimentally relevant parameter values, the results are independent of the short-wavelength cutoff needed in the model and can be checked against the theory of conformai covariance at two-dimensional critical points. It is found that the finite-size effects in capillary-rise measurements of surface tension vary as 1/D ² (with a universal coefficient) but are too small to be seen in current experiments.Invited paper presented at the Tenth Symposium on Thermophysical Properties, June 20–23, 1988, Gaithersburg, Maryland, U.S.A.     

Viewfinder Alignment

The viewfinder of a digital camera has traditionally been used for one purpose: to display to the user a preview of what is seen through the camera's lens. High quality cameras are now available on devices such as mobile phones and PDAs, which provide a platform where the camera is a programmable device, enabling applications such as online computational photography, computer vision‐based interactive gaming, and augmented reality. For such online applications, the camera viewfinder provides the user's main interaction with the environment. In this paper, we describe an algorithm for aligning successive viewfinder frames. First, an estimate of inter‐frame translation is computed by aligning integral projections of edges in two images. The estimate is then refined to compute a full 2D similarity transformation by aligning point features. Our algorithm is robust to noise, never requires storing more than one viewfinder frame in memory, and runs at 30 frames per second on standard smartphone hardware. We use viewfinder alignment for panorama capture, low‐light photography, and a camera‐based game controller.     

Tree-structured piecewise linear adaptive equalization

The use of a tree-structured piecewise linear filter as an adaptive equalizer is proposed. In the tree equalizer, each node in a tree is associated with a linear filter restricted to a polygonal domain, and each subtree is associated with a piecewise linear filter. A training sequence is used to adaptively update the filter coefficients and domains at each node, and to select the best subtree and corresponding piecewise linear filter. The tree-structured approach offers several advantages. First, it makes use of standard linear adaptive filtering techniques at each node to find the corresponding conditional linear filter. Second, it allows for efficient selection of the subtree and corresponding piecewise linear filter of appropriate complexity. Overall, the approach is computationally efficient and conceptually simple. Numerical experiments are performed to show the advantages of tree-structured piecewise linear and piecewise decision feedback equalizers over linear, polynomial, and decision feedback equalizers for the equalization of channels with severe intersymbol interference     

Converging measurement of horizontal and vertical individualism and collectivism.

The constructs of horizontal (H) and vertical (V) individualism (I) and collectivism (C) were theoretically defined and empirically supported. Study 1 confirmed, via factor analysis, that the 4 constructs, HI, V1, HC, and VC, which were previously found in the United States, which has an individualist culture, also were found in Korea which has a collectivist culture. Study 2 investigated multimethod-multitrait matrices measuring the constructs and generally supported their convergent and divergent validity. Study 3 showed how these 4 constructs relate to previously identified components by H. C. Triandis and colleagues. Study 4 showed the relationships of the measurement of the 4 constructs to some of the measures used by other researchers. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Spatial modeling for groundwater arsenic levels in North Carolina

To examine environmental and geologic determinants of arsenic in groundwater, detailed geologic data were integrated with well water arsenic concentration data and well construction data for 471 private wells in Orange County, NC, via a geographic information system. For the statistical analysis, the geologic units were simplified into four generalized categories based on rock type and interpreted mode of deposition/emplacement. The geologic transitions from rocks of a primary pyroclastic origin to rocks of volcaniclastic sedimentary origin were designated as polylines. The data were fitted to a left-censored regression model to identify key determinants of arsenic levels in groundwater. A Bayesian spatial random effects model was then developed to capture any spatial patterns in groundwater arsenic residuals into model estimation. Statistical model results indicate (1) wells close to a transition zone or fault are more likely to contain detectible arsenic; (2) welded tuffs and hydrothermal quartz bodies are associated with relatively higher groundwater arsenic concentrations and even higher for those proximal to a pluton; and (3) wells of greater depth are more likely to contain elevated arsenic. This modeling effort informs policy intervention by creating three-dimensional maps of predicted arsenic levels in groundwater for any location and depth in the area.     

Methotrexate treatment of idiopathic granulomatous hepatitis

OBJECTIVE: To test the efficacy and safety of low-dose oral pulse methotrexate therapy in patients with idiopathic granulomatous hepatitis who had complications of, did not respond to, or refused glucocorticoid therapy. DESIGN: Prospective case study. SETTING: Academic medical center hospital. PATIENTS: Seven patients with biopsy-proven, idiopathic granulomatous hepatitis who could not tolerate or were unresponsive to glucocorticoid therapy. INTERVENTION: Low-dose oral pulse methotrexate, 15 mg/wk. MEASUREMENTS: Temperature, symptoms, dose of concurrent glucocorticoids, biochemical tests of liver function, side effects of methotrexate, and assessment of liver biopsy specimens. RESULTS: All six febrile patients became afebrile within 3 months of starting methotrexate. Fatigue and anorexia improved in all patients. Glucocorticoid therapy was successfully discontinued within 6 months of starting methotrexate in four patients receiving prednisone at entry. Liver biopsy specimens were obtained again after methotrexate therapy and showed absence of granulomas in four of four patients. The minimum effective dose of methotrexate was 0.20 mg/kg body weight per week. No serious adverse effects and no failures to respond to methotrexate therapy were noted in this group of patients. In three patients, methotrexate therapy has been successfully tapered without signs or symptoms of recurrent disease. CONCLUSIONS: Low-dose oral pulse methotrexate was effective in treating patients with granulomatous hepatitis.     

The relationship of current psychiatric disorder to functional disability and distress in patients with inflammatory bowel disease

Although prior theories about psychiatric disorders causing inflammatory bowel disease (IBD) have largely been discredited, these same disorders have at times been associated with functional gastrointestinal symptoms such as those found in irritable bowel syndrome. Since functional gastrointestinal symptoms can also occur in patients with organic pathology, we hypothesized that a current psychiatric disorder might amplify or produce additional gastrointestinal symptoms in patients with organic gastrointestinal diseases such as IBD, leading to additive functional disability and decreased quality of life. This pilot study evaluated a sequential sample of 40 IBD patients using the NIMH Diagnostic Interview Schedule, structured interviews for functional gastrointestinal symptoms, and prior episodes of emotional, physical, and sexual abuse as well as self-report measures of personality and disability. We compared IBD patients with and without a current psychiatric disorder while controlling for disease severity. Eight patients with major depression were treated with antidepressants. Patients with a current psychiatric disorder had significantly higher 1) mean number of lifetime psychiatric diagnoses, 2) prevalence rates of prior sexual and physical victimization, and, 3) mean numbers of both gastrointestinal and other medically unexplained symptoms despite no differences in severity of IBD. Significant and trend level differences were apparent on several measures of functional disability. A regression analysis showed that number of psychiatric diagnoses, number of functional gastrointestinal symptoms, and dissociation scale scores significantly discriminated the groups. Treatment of current major depression decreased functional disability despite no objective changes in gastrointestinal disease severity. It was concluded that the presence of a current psychiatric disorder appears to alter the perception of disease severity in patients with IBD. Nonrecognition of the psychiatric disorder may lead to unnecessary and aggressive interventions for IBD patients such as medication changes, invasive testing, or surgery. The presence of a current psychiatric illness also appears to be associated with increased functional disability. Psychiatric evaluation and treatment, therefore, have an important role in the ongoing management of IBD patients with distressing gastrointestinal symptoms not directly attributable to their IBD.     

Clinical precision of the Rinne test

The precision of the Rinne test at 128-2048 Hz was studied in 100 ears with confirmed conductive pathologies. The number of negative (diagnostic) Rinnes decreased significantly with fall in frequency. While there were significantly more negative than positive Rinnes at 128 and 256 Hz, there were significantly more positive results at higher frequencies; indicating that the Rinne is not reliably diagnostic above 256 Hz. However, the possibility of vibrotactile responses must be remembered with low frequency tuning forks. Also, conductive lesions manifested as high tone air-bone gaps will not be identified with low frequency Rinne tests. Air-bone gaps of 25 to 40 dB, depending on frequency, are necessary for the Rinne to identify the presence of conductive components in most cases. Gaps of 25-30 dB for 128 Hz; 35-40 dB for 256 Hz; 55-60 dB for 512 Hz; and 45-50 dB for 1024 Hz, are necessary for the Rinne to meet a 75% correct detection criterion. The 2o48 Hz Rinne does not attain even chance detection. The Rinne test cannot be validly employed as a criterion against which other measures can be evaluated.     

The Psychologist in community mental health.

It is "our belief that the field of community mental health is a challenging and stimulating field for research oriented psychologists. We feel strongly that the identity of the psychologist may be best maintained through a scientist-professional model." Recommendations are made for the future training of psychologists in this field. The individual psychologist "must be assisted by adequate post-doctoral interdisciplinary training in a university setting." Major sections are: Maintenance of an Identity, Scientist and Professional, and Training the Scientist-Professional. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

The relevance of hypnotic susceptibility in the clinical context.

Comments that despite experimental evidence that hypnotic susceptibility is a relatively stable characteristic of the individual, and one that is difficult to modify, clinical investigators tend to see susceptibility as irrelevant to therapeutic outcome. Such investigators view motivational and interpersonal variables as more essential to the therapeutic change. The evidence for the clinical relevance of hypnotizability is sparse and contradictory. Most studies stem from medical hypnosis and indicate that susceptibility plays an important role in the successful treatment of such conditions as clinical pain, warts, and asthma. Two studies are reported that pursue a contrary finding reported by C. Perry and G. Mullen (see record 1976-30394-001), who found that susceptibility was unrelated to the successful treatment of a socially learned behavior (cigarette smoking). Both studies confirmed the earlier finding of a lack of relation. In Study 1, however, stepwise multiple regression analysis located 3 inventory items concerning the motivation of cigarette smokers. The combination of items was found to predict outcome for 67.39% of 46 clients treated either by hypnosis or by rapid smoking. The finding was replicated in Study 2, which utilized a combined hypnosis/rapid smoking technique and employed a different therapist. The outcome for 9 of the 13 quitters and 37 of the 62 nonquitters across the 2 studies could be predicted by the 3 motivational questionnaire variables. (59 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)