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This study tested assumptions and conclusions reached in an earlier confirmatory factor analysis (CFA) study of the social competence (SC) construct for preschool children. Two samples (total N = 408; a new Portuguese sample and one from US samples that had participated in the original study) contributed data. Seven SC indicators were tested for mean differences across age, sex, and sample. Significant sex differences were found for peer acceptance (favoring girls) and for initiating affectively neutral interactions (boys had higher rates), and the sex by sample interaction also was significant for initiating interactions (i.e., effect significant only in the Portuguese sample). In CFAs, the hypothesized structure of SC fits the data and was invariant across sample and age within sample in both measurement and structural tests. The model was invariant at the measurement level for sex within sample tests, but not at the structural level. The results replicate and extend understandings of SC reported in the original study. (Contains 4 tables and 1 figure.)

The evolutionary rationale offered by Bowlby implies that secure base relationships are common in child-caregiver dyads and thus, child secure behavior observable across diverse social contexts and cultures. This study offers a test of the universality hypothesis. Trained observers in nine countries used the Attachment Q-set to describe the organization of children's behavior in naturalistic settings. Children (N = 547) were 10-72 months old. Child development experts (N = 81) from all countries provided definitions of optimal child secure base use. Findings indicate that children from all countries use their mother as a secure base. Children's organization of secure base behavior was modestly related to each other both within and across countries. Experts' descriptions of the optimally attached child were highly similar across cultures.

Attachment research suggests that children with secure attachments are more able to construct meaningful relationships with peers. Few studies, however, have attempted to map early attachment security to the formation and maintenance of preschool friendships. Special attention has been paid to affiliative relationships (particularly friendships) because these are presumed to be of special importance with respect to a number of developmental outcomes and social adjustment indices. This study examined the relations between mother-child and father-child attachment relationships using the attachment Q-sort (AQS) and the number of reciprocated friendships of preschool children. Thirty-five mother-child and father-child dyads from bi-parental families participated in the study. Children were between 29 and 38 months of age for the first assessment. The organisation of children's secure base behaviour with both parents was assessed from separate observations of the child and parent at home. Subsequently, sociometric measures were used at four years of age to determine peer preferences. The correlation between the independent AQS scores for fathers and mothers was positive and significant (r = 0.51, p less than 0.05). Thus, there was consistency in child secure base behaviour across visits with each parent. Bivariate correlation and regression analyses showed a significant positive relation between AQS security with fathers (but not with mothers) and the number of reciprocated friendships (r = 0.43, p less than 0.05). Regression analyses indicated that AQS security with fathers remained a significant predictor of friendships even when AQS security with mothers was controlled. These findings may indicate a distinct relational effect of interaction quality with the father. (Contains 2 tables.)

Morphogenesis and remodeling of bone involve synthesis of bone matrix by osteoblasts and coordinate resorption of bone by osteoclasts. Defective bone remodeling caused by altered osteoclast activity underlies a multitude of osteopenic disorders. Receptor activator of NF-[kappa]B (RANK) and its ligand RANKL have been identified as essential factors involved in osteoclast development and bone remodeling, but their mechanism and interacting factors have not been fully characterized. Here we report that the molecular adapter Grb-2-associated binder-2 (Gab2) associates with RANK and mediates RANK-induced activation of NF-[kappa]B, Akt and Jnk. Inactivation of the gene encoding Gab2 in mice results in osteopetrosis and decreased bone resorption as a result of defective osteoclast differentiation. We also show that Gab2 has a crucial role in the differentiation of human progenitor cells into osteoclasts. We have thus identified a new, key regulatory scaffold molecule, Gab2, that controls select RANK signaling pathways and is essential for osteoclastogenesis and bone homeostasis., Author(s): Teiji Wada (corresponding author) [1]; Tomoki Nakashima [1]; Antonio J Oliveira-dos-Santos [2]; Juerg Gasser [3]; Hiromitsu Hara [1]; Georg Schett [4]; Josef M Penninger (corresponding author) [1] The accumulation [...]

Research has been conducted on the PI3K/PTEN signaling pathways. The study of cardiomycete-specific inactivation of tumor suppressor PTEN leading to cardiac contractility disease has been carried out and the role of PTEN in cardiomyocyte hypertrophy and GPCR signaling and the functions of PI3K/PTEN pathway in heart muscle contractility modulation are discussed.

Author(s): Michael A. Crackower [1, 2, 3]; Renu Sarao [1, 4, 5]; Gavin Y. Oudit [3, 5, 6, 7]; Chana Yagil [8]; Ivona Kozieradzki [1, 4]; Sam E. Scanga [9]; [...]

Results demonstrate that the calcium-sensing protein DREAM is involved in pain processing. Mutants lacking this protein respond poorly to acute thermal, mechanical, and visceral pain as well as to chronic neuropathic and inflammatory pain.

The process of morphogenesis and remodelling of bone is controlled physiologically with the synthesis of bone matrix by osteoblasts and resorption of bone by osteoclasts. It has been found that the new TNF-family molecule osteoprotegerin ligand (OPGL) can activate mature osteoclasts and mediate osteoclastogenesis in the presence of colony-stimulating factor-1 (CSF-1). Studies have shown that the molecule is an important factor in early differentiation of thymocytes and B-cell precursors, and opgl-1- mice were found to lack lymph nodes.

In this work, a simple, fast and dry method for the fabrication of a thermochromic product with a high load of VO2(M1) consisting of the controlled heat treatment of pure vanadium nanoparticles in air is presented. After a complete design of experiments, it is concluded that the most direct way to attain the maximum transformation of V into VO2(M1) consists of one cycle with a fast heating ramp of 42 °C s−1, followed by keeping 700 °C for 530–600 seconds, and a subsequent cooling at 0.05 °C s−1. Careful examination of these results lead to a second optimum, even more suitable for industrial production (quicker and less energy‐intensive because of its lower temperatures and shorter times), consisting of subjecting V to two consecutive cycles of temperatures and times (625 °C for 5 minutes) with similar preheating (42 °C s−1) but a much faster postcooling (∼ 8 °C s−1). These green reactions only use the power for heating a tube open to atmosphere and a vanadium precursor; without assistance of reactive gases or catalysts, and no special vacuum or pressure requirements. The best products present similar thermochromic properties but higher thermal stability than commercial VO2 particles. These methods can be combined with VO2 doping. [ABSTRACT FROM AUTHOR]

The ecological modulation affects sex roles in a natural population of the blenniid fish, Salaria pavo. The female initiation of mating predominates over male intra-sexual competition, active courtship and developed epigamic characters in males. More than one female of S. pavo comes to the nest and each female mates with different males during the breeding season. The males are selective in admitting the females to the nest. The ability of females to spawn determines the male courtship behavior for the nest sites.

Regulators of G protein signaling (RGS) proteins accelerate the GTPase activity of G[Alpha] protein subunits in vitro, negatively regulating G protein-coupled receptor signaling. The physiological role of mammalian RGS proteins is largely unknown. The RGS family member rgs2 was cloned as an immediate early response gene up-regulated in T lymphocytes after activation. To investigate the role of RGS2 in vivo, we generated rgs2-deficient mice. We show that targeted mutation of rgs2 in mice leads to reduced T cell proliferation and IL-2 production, which translates in an impaired antiviral immunity in vivo. Interestingly, rgs[2.sup.-/-] mice also display increased anxiety responses and decreased male aggression in the absence of cognitive or motor deficits. RGS2 also controls synaptic development and basal electrical activity in hippocampal CA1 neurons. Thus, RGS2 plays an important role in T cell activation, synapse development in the hippocampus, and emotive behaviors.