Pseudo-precocious puberty in a male patient and the melatonin-testosterone relationship

We describe a 14 year-old boy with a pineal germ cell tumor which secreted beta HCG. Serum testosterone levels were markedly elevated with concomitant decreased LH secretion. 24-h serum melatonin levels were suppressed and lacked the normal nocturnal rise. Pineal radiation therapy was followed by tumor regression and the diminution of beta HCG stimulated testosterone, which in turn inhibited melatonin and LH. When beta HCG and testosterone were normalized after tumor radiation, a recovery of normal melatonin and LH secretory pattern occurred. These results indicate that circulating testosterone down-regulates pineal melatonin.     

Sleep patterns of children sleeping in residential care, in kibbutz dormitories and at home--a comparative study

The present study compares sleep patterns of two groups of children sleeping away from their families, in residential care (n = 31, age 3.7 +/- 1.7 years) and kibbutz (n = 29, age 3.7 +/- 1.8 years) dormitories, with age-matched children sleeping at home (n = 21, age 3.7 +/- 1.8 years). Sleep was monitored by wrist-worn actigraphs for three consecutive nights and assessed by sleep questionnaires, which were completed by parents of the kibbutz children and caretakers at residential care. Children in the residential care settled to sleep significantly earlier and slept longer than those children living in a kibbutz or at home. The longest period of uninterrupted sleep was more extended for children sleeping at home, compared to those sleeping in communal dormitories. Correlation analysis between various assessments of sleep and waking behaviors revealed a different pattern for kibbutz and residential care children. For the kibbutz children, there were significant correlations between difficulties falling asleep and various attributes of daytime tiredness. Conversely, in the residential care, difficulties falling asleep were significantly and positively correlated with parameters associated with daytime alertness. This pattern of correlations and the actigraphic data indicate that difficulties in falling asleep for children in residential care are probably a consequence of being put to bed too early and according to a rigid schedule, and not the result of emotional factors.     

The impact of Arabic morphological segmentation on broad-coverage English-to-Arabic statistical machine translation

Morphologically rich languages pose a challenge for statistical machine translation (SMT). This challenge is magnified when translating into a morphologically rich language. In this work we address this challenge in the framework of a broad-coverage English-to-Arabic phrase based statistical machine translation (PBSMT). We explore the largest-to-date set of Arabic segmentation schemes ranging from full word form to fully segmented forms and examine the effects on system performance. Our results show a difference of 2.31 BLEU points averaged over all test sets between the best and worst segmentation schemes indicating that the choice of the segmentation scheme has a significant effect on the performance of an English-to-Arabic PBSMT system in a large data scenario. We show that a simple segmentation scheme can perform as well as the best and more complicated segmentation scheme. An in-depth analysis on the effect of segmentation choices on the components of a PBSMT system reveals that text fragmentation has a negative effect on the perplexity of the language models and that aggressive segmentation can significantly increase the size of the phrase table and the uncertainty in choosing the candidate translation phrases during decoding. An investigation conducted on the output of the different systems, reveals the complementary nature of the output and the great potential in combining them.     

Aesthetics and usability of in-vehicle navigation displays

This research evaluates the aesthetics and usability of various in-vehicle electronic navigation map configurations. Study 1 adapted the aesthetics scale (Lavie and Tractinsky, 2004) to accommodate evaluations of map displays. Study 2 examined map displays that vary in the amount of data presented, their abstraction level and color schema, using objective and subjective usability measures. Maps with minimal detail produced best performances and highest evaluations. Abstractions were found to be advantageous when combined with reduced amount of detail and specific color schemas. Moderate abstractions were sufficient for obtaining the desired benefits. The color schema mainly affected the objective measures, pointing to the importance of good contrast between the cursor and the map colors. Study 3 further examined map schemas. Color schemas again had no effect on the perceptions of aesthetics and usability. Overall, similar results and high correlations were found for the perceived aesthetics and usability scales, indicating the connection between perceived aesthetics and usability. Lower correlations were found between the actual usability (performance) and the aesthetics scale. Finally, users’ usability evaluations were not always in line with their actual performance, pointing to the importance of using objective usability measures.     

Iterative estimation of eigenmodes for acoustic cavities

In this paper, a stochastic estimation method of the number of eigenvalues of nonlinear eigenproblem (initially proposed by Maeda et al., JSIAM Letters 3, 61-64, (2011)) is employed iteratively in order to identify eigenvalues of acoustic cavities. Applied to several discretization formulations of the Helmholtz equation, the proposed approach handles complex acoustic cavities. Specific developments are carried out concerning the approximation of the stochastic estimator for the solved kernels. The method's accuracy is illustrated with academic nonlinear eigenproblems with various boundary conditions. In particular, a sphere problem with constant surface impedance is solved and validated by comparison with results issued from a finite element method software.     

Constituents of Withania Somnifera Dun. Part X The Structure of Withanolide D

Withanolide D, the major component of the leaves of Withania somnifera chemotype II, is a steroidal lactone of the withanolide type, isomeric with withaferin A. It has been identified as 5, 6β-epoxy-4β, 20α-dihydroxy-1-oxo-(5β)witha-2, 24-dienolide. The structure has been elucidated by NMR measurements and by chemical degradation to 4β-acetoxy-5,6β-epoxy (5β) pregnan-1, 20-dione.     

A mixed-mode damage model for delamination growth applied to a new woven composite

In this paper, delamination initiation and propagation of reinforced fibrous composite laminate, in single and mixed mode, are numerically predicted by taking into account the existence of imperfect interfaces between the plies. The bonding conditions between layers are characterised by jumps in displacements which are proportional to the traction stresses. In order to describe the interface damage an approach based on the indirect use of fracture mechanics considering a softening stress-relative displacements law is presented. The accuracy of the predictions is evaluated in single-mode delamination tests, in the mixed-mode bending test, and in a structural configuration consisting of the debonding of a new woven laminated composite reinforced by particles of date cores for orthopedic use. The interface is regarded as being a whole of several interfacial bonds. Each bond is supposed to be made up of three stiffnesses acting in the three directions.     

Limit cycles in fixed beds operated in alternating modes

Fixed beds, exchanging mass or energy with a flowing fluid according to a linear phenomenological law, are considered. When the plant is alternated periodically between two sets of operating conditions, the state of the fixed bed converges to a limit cycle. The nature of this cycle is explored for co-current and counter-current operation.     

Tamoxifen activates cellular phospholipase C and D and elicits protein kinase C translocation

This epidemiological study focuses on cognitive change related to psychotropic drug use in a population-based sample of subjects aged 65 and over. Cognitive functioning was assessed in 1982 and 1988 by the Short Portable Mental Status by Pfeiffer, and cognitive decline was defined as an increase of more than 2 errors in 1988 relative to the 1982 assessment. Psychotropic drugs were classified into benzodiazepines and non-benzodiazepines. For both medications, four patterns of intake were considered: no use reported at both interviews, continuous use at both interviews, temporary use at the 1982 interview and new use at the 1988 interview. Depressive symptomatology was assessed by the Center for Epidemiologic Studies Depression Scale. The analysis was performed on 1200 subjects with no or minimal impairment at baseline for whom complete data were available. Univariate analyses showed cognitive decline associated with gender, level of education and new medical condition; it was also related to depressive symptomatology and psychotropic drug use. These two factors were the most strongly associated with decrease in performance in multivariate analyses. Cognitive decline differed according to class of psychotropic drugs and pattern of use: benzodiazepine temporary users exhibited a lower risk compared with never users (OR = 0.23, p = 0.056), non-benzodiazepine new users a higher risk (OR = 5.02, p < 0.001). Despite the simple measures of cognitive functioning and psychopathology, and the approximation in pattern of psychotropic drug use, these results emphasize the importance of considering psychotropic drugs in studies of cognitive decline in elderly subjects.     

The role of perceptual load in negative priming.

Negative priming (NP) effects from irrelevant distractors were assessed as a function of perceptual load in the processing of prime targets. Participants searched for a target letter among a varying number of nontarget letters in the center of the display and ignored an irrelevant peripheral distractor. NP from this distractor was found to depend on the relevant search set size, decreasing as this set size was increased. The authors conclude that exhausting attention in relevant processing reduces irrelevant processing (e.g., N. Lavie, 1995), leaving less distractor processing to produce NP. This conclusion is consistent with recent reactive inhibition views for NP (e.g., G. Houghton, S. P. Tipper, B. Weaver, & D. I. Shore, 1996). (PsycINFO Database Record (c) 2010 APA, all rights reserved)