The contingent smile: A meta-analysis of sex differences in smiling.

The authors present a meta-analysis of sex differences in smiling based on 448 effect sizes derived from 162 research reports. There was a statistically significant tendency for women and adolescent girls to smile more than men and adolescent boys (d=0.41). The authors hypothesized that sex differences in smiling would be larger when concerns about gender-appropriate behavior were made more conspicuous, situational constraints were absent or ambiguous, or emotion (especially negative) was salient. It was also predicted that the size of the sex difference in smiling would vary by culture and age. Moderator analysis supported these predictions. Although men tend to smile less than women, the degree to which this is so is contingent on rules and roles. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Conception d'une membrane filtrante a base d'alginate pour la concentration des virus hydriques

The isolation of traces of infectious agents in water supplies aims at ensuring the elaboration of qualitative and quantitative studies on the origin and the distribution of enteric viruses in aquatic media, and at obtaining adequate control in the estimation of water treatment efficiency. Among the research techniques of water viruses by concentration the use of soluble ultrafilters, composed of gelified alginate, guarantees water free from colloidal impurities and low in viral units. The use of small volumes of water then determines the functioning and the limits of application of the method of hyperfiltration through commercial alginate membrane.Study of the reduction of these experimental limitations is made in this work by a chemical alginate conditioning (introduction of soluble membranous additives such as sodium gluconate and the surface active agent Tween 80), which aims at modifying the filtering characteristics of the alginic membranes. Moreover the search for a bi-layered membrane, aiming simultaneously at an auto-induced filtrability of the unitary membranes and an efficient retention of the Poliovirus type 1, has led to a realization of the existence of stratification of alginate-sodium gluconate (superior membrane) and alginate-Tween 80 (inferior membrane) layers.The result of filtrability tests (using distilled water) shows that the filtering capacity of the pure 0.5% alginate unitary membranes (with a cumulative filtered volume of 101.), increases directly with an increase of the intramembranous concentration of sodium gluconate. The filtration output of pure 0.75% alginate membranes (51. filtered volume), stays critically constant for intramembranous Tween 80 concentrations <0.5%. The formation of membranous stratification by simple association of pure 0.5% with 0.75% alginic membranes, shows that the weak filtration rate of multiple alginate membrane is attributable to the cumulative loss of head through the bimembrane.Evaluation of the retention efficiency of the Poliomyelitis type 1 virus, by simple and two-phased ultrafiltration has shown that the use of a concentration of 0.75% sodium gluconate reduced the virus content of effluent from 0.5% alginate membranes, whereas a high concentration of 0.5% Tween 80 was unfavourable to viral retention in the single 0.75% alginate membranes. The recovery of virus collection from the layered pure and modified (0.75% sodium gluconate) alginate membranes, indicates a total absence of Poliovirus in the filtrate of the bimembranes.The special treatment of natural supply waters weakly contaminated (necessitating a concentration factor of or more than 500), might then be considered in order to estimate the efficiency of the removal of the colloidal impurities by layered alginic membranes containing 0.75% sodium gluconate. Moreover, promotion of hydrophobic polymer-virus interactions may be compatible with the conservation of a satisfactory permeability of membrane only for a weak concentration in surface-active non-ionic agent.     

Reciprocal subtraction differential RNA display: an efficient and rapid procedure for isolating differentially expressed gene sequences

A reciprocal subtraction differential RNA display (RSDD) approach has been developed that permits the rapid and efficient identification and cloning of both abundant and rare differentially expressed genes. RSDD comprises reciprocal subtraction of cDNA libraries followed by differential RNA display. The RSDD strategy was applied to analyze the gene expression alterations resulting during cancer progression as adenovirus-transformed rodent cells developed an aggressive transformed state, as documented by elevated anchorage-independence and enhanced in vivo oncogenesis in nude mice. This approach resulted in the identification and cloning of both known and a high proportion (>65%) of unknown sequences, including cDNAs displaying elevated expression as a function of progression (progression-elevated gene) and cDNAs displaying suppressed expression as a function of progression (progression-suppressed gene). Sixteen differentially expressed genes, including five unknown progression-elevated genes and six unknown progression-suppressed genes, have been characterized. The RSDD scheme should find wide application for the effective detection and isolation of differentially expressed genes.     

Higher Order Assembly of Virus‐like Particles (VLPs) Mediated by Multi‐valent Protein Linkers

Two‐ and three‐dimensional assembly of nanoparticles has generated significant interest because these higher order structures could exhibit collective behaviors/properties beyond those of the individual nanoparticles. Highly specific interactions between molecules, which biology exploits to regulate molecular assemblies such as DNA hybridization, often provide inspiration for the construction of higher order materials using bottom‐up approaches. In this study, higher order assembly of virus‐like particles (VLPs) derived from the bacteriophage P22 is demonstrated by using a small adaptor protein, Dec, which binds to symmetry specific sites on the P22 capsid. Two types of connector proteins, which have different number of P22 binding sites and different geometries (ditopic linker with liner geometry and tetratopic linker with tetrahedral geometry) have been engineered through either a point mutation of Dec or genetic fusion with another protein, respectively. Bulk assembly and layer‐by‐layer deposition of P22 VLPs from solution was successfully achieved using both of the engineered multi‐topic linker molecules, while Dec with only a single binding site does not mediate P22 assembly. Beyond the two types of linkers developed in this study, a wide range of different connector geometries could be envisioned using a similar engineering approach. This is a powerful strategy to construct higher order assemblies of VLP based nanomaterials.     

What are experts for?

Knowledge engineering is the term given to the process of developing expert systems and knowledge engineers are the people who acquire the requisite knowledge from experts and structure that knowledge into a useable computer program. As knowledge engineering becomes a more accepted technology, there is increasing concern about attendant social costs, such as job displacement or possible exploitation of experts. This paper reports on our efforts to explore this latter issue by scrutinizing how knowledge engineers think about the domain expert and the role that person plays in system development. To accomplish this aim, we asked several samples of novice engineers to write story completions to a preamble that describes a knowledge engineer encountering a reluctant expert who may be fearing job loss if the system is implemented. The resulting accounts were content-analysed for insights as to how novice system builders think about experts. The results indicate that experts are conceived more as a tool to be used rather than a person to be respected.Preparation of this chapter was supported by National Science Foundation Grant BNS 87-21882 to Marianne LaFrance.     

Altered cortical blood flow in HIV-seropositive individuals with and without dementia: a single photon emission computed tomography study

OBJECTIVE: To quantitatively demonstrate the pattern of cerebral perfusion abnormalities in HIV-1-infected individuals described as 'patchiness' or inhomogeneity in previous qualitative emission tomographic imaging studies. DESIGN: We aimed to create a quantitative measure of inhomogeneity in HIV-infected individuals. High-frequency variance in cortical profiles is an indication of inhomogeneity in the distribution of radiotracer in the cerebral cortex. Therefore, the study analysis was designed to enable the estimation of variance frequencies in cortical profiles. METHODS: Regional cerebral blood flow was examined in nine mildly demented and 10 cognitively normal HIV-1-seropositive individuals and eight seronegative normal controls using single photon emission computed tomography with the radiotracer [I-123]-N-isopropyl-p-iodoamphetamine. Quantitative analysis was performed using circumferential profiles of cerebral cortical perfusion. Fourier transform power spectra of the profiles were examined as an index of patchiness in tracer distribution. RESULTS: Normal controls were characterized by strong middle frequency and weak high-frequency power. Both HIV-1-infected groups showed a significant power shift from middle to high frequencies. CONCLUSIONS: Increased high-frequency variations in both HIV-1-infected groups indicates diffuse cortical perfusion changes compared with normal controls. This study suggests that there are cerebral bloodflow abnormalities in HIV-1-infected individuals both with and without clinically severe dementia.     

Conception d'une membrane filtrante a base d'alginate pour la concentration des virus hydriquesApplication of a multiple alginate filter method for the determination of water viruses concentration

The isolation of traces of infectious agents in water supplies aims at ensuring the elaboration of qualitative and quantitative studies on the origin and the distribution of enteric viruses in aquatic media, and at obtaining adequate control in the estimation of water treatment efficiency. Among the research techniques of water viruses by concentration the use of soluble ultrafilters, composed of gelified alginate, guarantees water free from colloidal impurities and low in viral units. The use of small volumes of water then determines the functioning and the limits of application of the method of hyperfiltration through commercial alginate membrane.Study of the reduction of these experimental limitations is made in this work by a chemical alginate conditioning (introduction of soluble membranous additives such as sodium gluconate and the surface active agent Tween 80), which aims at modifying the filtering characteristics of the alginic membranes. Moreover the search for a bi-layered membrane, aiming simultaneously at an auto-induced filtrability of the unitary membranes and an efficient retention of the Poliovirus type 1, has led to a realization of the existence of stratification of alginate-sodium gluconate (superior membrane) and alginate-Tween 80 (inferior membrane) layers.The result of filtrability tests (using distilled water) shows that the filtering capacity of the pure 0.5% alginate unitary membranes (with a cumulative filtered volume of 101.), increases directly with an increase of the intramembranous concentration of sodium gluconate. The filtration output of pure 0.75% alginate membranes (51. filtered volume), stays critically constant for intramembranous Tween 80 concentrations <0.5%. The formation of membranous stratification by simple association of pure 0.5% with 0.75% alginic membranes, shows that the weak filtration rate of multiple alginate membrane is attributable to the cumulative loss of head through the bimembrane.Evaluation of the retention efficiency of the Poliomyelitis type 1 virus, by simple and two-phased ultrafiltration has shown that the use of a concentration of 0.75% sodium gluconate reduced the virus content of effluent from 0.5% alginate membranes, whereas a high concentration of 0.5% Tween 80 was unfavourable to viral retention in the single 0.75% alginate membranes. The recovery of virus collection from the layered pure and modified (0.75% sodium gluconate) alginate membranes, indicates a total absence of Poliovirus in the filtrate of the bimembranes.The special treatment of natural supply waters weakly contaminated (necessitating a concentration factor of or more than 500), might then be considered in order to estimate the efficiency of the removal of the colloidal impurities by layered alginic membranes containing 0.75% sodium gluconate. Moreover, promotion of hydrophobic polymer-virus interactions may be compatible with the conservation of a satisfactory permeability of membrane only for a weak concentration in surface-active non-ionic agent.     

Obituary: Clara Mayo (1931-1981).

Obituary [Clara Mayo; 1931-1981]. When she died, Clara Mayo's teaching, researching, writing, and administering were very much in motion. Her primary goal, as always, was to understand and alleviate prejudice, sexism, and racism. Clara Mayo was a complete teacher, an indefatigable colleague, and a collaborator par excellence. In all three she urged us to be committed, and she showed us how to think and act with subtlety, passion, detachment, verve, and yes, with fun. Clara Mayo was committed to intellectual adventure and social justice, and in that she saw no contradiction and no end. (PsycINFO Database Record (c) 2010 APA, all rights reserved)