State variations in the newborn and mother–infant interaction during breast feeding: Some sex differences.

30 male and 33 female newborns were observed being breast-fed in the maternity ward. The conditional probabilities of various maternal and infant behaviors were studied when the infant was in 1 of 4 states: asleep, drowsy, fussy, and crying. Although male dyads showed more interactive activity on the asleep end of the scale, female dyads showed more interactive activity on the awake end of the scale. These interaction episodes were characterized by greater physical proximity in male dyads and more social interaction in female dyads. Although male neonates spent less time than females in the fussy state, when they were in this state, they seemed to be more agitated than the females. A relatively high proportion of simultaneous vocalization was observed in dyads of both sexes during the fussy state. Results are qualified by the great individual differences observed among the neonates in the amount of time spent in each of the states. (15 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Support for psychologists in the population and family planning areas.

Describes the sources (federal and private) and extent of financial support for population research, training, and services among psychologists. An analysis is provided of critical comments made by reviewers concerning behavioral–social science population research proposals. Discussion includes research design and measurement techniques. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

The effects of shoulder load and pinch force on electromyographic activity and blood flow in the forearm during a pinch task

The object of the current study was to determine whether static contraction of proximal musculature has an effect on the blood flow more distally in the upper extremity. Static contractions of muscles in the neck shoulder region at three levels (relaxed, shoulders elevated and shoulders elevated loaded with 4.95 kg each) were combined with intermittent pinch forces at 0, 10 and 25% of the maximum voluntary contraction (MVC). Blood flow to the forearm was measured with Doppler ultrasound. Myoelectric activity of the forearm and neck-shoulder muscles was recorded to check for the workload levels. Across all levels of shoulder load, blood flow increased significantly with increasing pinch force (21% at 10% MVC and by 44% at 25% MVC). Blood flow was significantly affected by shoulder load, with the lowest blood flow at the highest shoulder load. Interactions of pinch force and shoulder load were not significant. The myoelectric activity of forearm muscles increased with increasing pinch force. The activation of the trapezius muscle decreased with increasing pinch force and increased with increasing shoulder load. The precise mechanisms accounting for the influence of shoulder load remains unclear. The results of this study indicate that shoulder load might influence blood flow to the forearm.     

Temporal decoding by phase-locked loops: unique features of circuit-level implementations and their significance for vibrissal information processing

Rhythmic active touch, such as whisking, evokes a periodic reference spike train along which the timing of a novel stimulus, induced, for example, when the whiskers hit an external object, can be interpreted. Previous work supports the hypothesis that the whisking-induced spike train entrains a neural implementation of a phase-locked loop (NPLL) in the vibrissal system. Here we extend this work and explore how the entrained NPLL decodes the delay of the novel, contact-induced stimulus and facilitates object localization. We consider two implementations of NPLLs, which are based on a single neuron or a neural circuit, respectively, and evaluate the resulting temporal decoding capabilities. Depending on the structure of the NPLL, it can lock in either a phase- or co-phase-sensitive mode, which is sensitive to the timing of the input with respect to the beginning of either the current or the next cycle, respectively. The co-phase-sensitive mode is shown to be unique to circuit-based NPLLs. Concentrating on temporal decoding in the vibrissal system of rats, we conclude that both the nature of the information processing task and the response characteristics suggest that the computation is sensitive to the co-phase. Consequently, we suggest that the underlying thalamocortical loop should implement a circuit-based NPLL.     

On the in vitro and in vivo properties of four locked nucleic acid nucleotides incorporated into an anti-H-Ras antisense oligonucleotide

Locked nucleic acid (beta-D-LNA) monomers are conformationally restricted nucleotides bearing a methylene 2'-O, 4'-C linkage that have an unprecedented high affinity for matching DNA or RNA. In this study, we compared the in vitro and in vivo properties of four different LNAs, beta-D-amino LNA (amino-LNA), beta-D-thio LNA (thio-LNA), beta-D-LNA (LNA), and its stereoisomer alpha-L-LNA in an antisense oligonucleotide (ODN). A well-known antisense ODN design against H-Ras was modified at the 5'- and 3'-ends with the different LNA analogues (LNA-DNA-LNA gapmer design). The resulting gapmers were tested in cancer-cell cultures and in a nude-mouse model bearing prostate tumor xenografts. The efficacy in target knockdown, the biodistribution, and the ability to inhibit tumor growth were measured. All anti H-Ras ODNs were very efficient in H-Ras mRNA knockdown in vitro, reaching maximum effect at concentrations below 5 nM. Moreover, the anti-H-Ras ODN containing alpha-L-LNA had clearly the highest efficacy in H-Ras knockdown. All LNA types displayed a great stability in serum. ODNs containing amino-LNA showed an increased uptake by heart, liver, and lungs as compared to the other LNA types. Both alpha-L-LNA and LNA gapmer ODNs had a high efficacy of tumor-growth inhibition and were nontoxic at the tested dosages. Remarkably, in vivo tumor-growth inhibition could be observed at dosages as low as 0.5 mg kg(-1) per day. These results indicate that alpha-L-LNA is a very promising member of the family of LNA analogues in antisense applications.     

The sex pheromone glands ofDermacentor variabilis (Say) andDermacentor andersoni stiles

Evidence is presented indicating the presence of the tick sex pheromone, 2,6-dichlorophenol in lipid droplets in the foveal glands ofDermacentor variabilis (Say) andDermacentor andersoni Stiles. The pheromone appears to be dissolved in the lipid droplets. The droplets consist of neutral lipids, mostly triacylglycerides and cholesterol esters. The esterified fatty acid profiles of foveal gland triacylgylcerides are different from those of other tissues examined or reported for other ticks. The percentage of shorter chain, mostly saturated fatty acids were decreased, while the longer chain polyunsaturated fatty acids were increased. The biological advantages of lipid solution for storage, translocation, and release of the sex pheromone from the female tick are discussed.Supported by grant AI 10986, from the National Institute of Allergy and Infectious Diseases, National Institutes of Health, U.S. Public Health Service, Department of Health, Education and Welfare, Bethesda, Maryland.     

The avrami index and the fractal dimension in vegetable oil crystallization

The behavior of the Avrami plot during TAG crystallization was studied by DSC and rheological measurements in oil blends of palm stearin (26 and 80%) in sesame oil, using different crystallization temperatures (T _Cr ^o) attained under several cooling rate conditions (1, 10, and 30°C/min). In the same way, the relationship between the growth mechanisms of TAG, measured by the Avrami index (n), and the mass fractal dimension (D) of the crystal network was investigated. This last parameter was measured as TAG crystallized in the oil blend under isothermal conditions. Results showed that TAG crystallization in a vegetable oil involves the process of TAG lamellar development, nucleation, and crystal growth. Each event occurred at a different rate and extent as affected by cooling rate and T _Cr ^o, and as a function of crystallization time under isothemal conditions at a given cooling rate. Within this framework, we proposed that n calculated from the second region of the Avrami plot is a parameter mainly associated with crystal growth, whereas n from the first region is associated more with nucleation. On the other hand, changes in D values followed the different polymorphic states developed by TAG as a function of T _Cr ^o. Additionally, it was shown that, independent of the concentration of palm stearin in the oil blend, at cooling rates of 1 and 10°C/min the increase in n from ∼3 to ∼4 produced a curvilinear increase in D from ∼1.75 to ∼3.0. The growth mechanism of the TAG crystals (i.e., n), also affected the magnitude of D. However different behavior was observed in the n-D relationship when n<2.7 and at 30°C/min.     

Electric current density distribution in planar solid tumor and its surrounding healthy tissue generated by an electrode elliptic array used in electrotherapy

The knowledge of the electric current density distribution generated by an electrode array is very useful in electrotherapy for tumor treatment. We propose an innovative mathematical approach that takes into account planar solid tumor elliptic geometry, electrical differences between it and its surrounding healthy tissue, and positioning of the electrodes with respect to tumor-surrounding healthy tissue interface. We show the distributions of the electric current density in leading order and first correction terms in a heterogeneous planar medium formed by two regions (tumor and its surrounding healthy tissue) in function of these parameters. The results show that when electrodes are completely inserted in tumor and/or its conductivity is higher than that of its surrounding healthy tissue, the electric current density lines concentrate more in tumor and its tumor-surrounding healthy tissue interface. No significant differences are reported between the electric current density distributions in leading-order and first-order correction for each parameter investigated. However, norm of this physical magnitude reveals that these distributions are different when the ratio between radius of the electrodes and radius of the tumor is less than 0.8. We conclude that the analytical modeling presented in this study is of practical interest because it provides a convenient way to visualize the electric current density distributions generated by an electrode elliptic array in order to efficiently destroy the localized planar tumors with the minimum damage to organism, through an increase of the potential applied to the electrodes, the tumor conductivity with respect to its surrounding healthy tissue and insertion of all electrodes into tumor.