Novel Homozygous Missense Variant in GJA3 Connexin Domain Causing Congenital Nuclear and Cortical Cataracts

Congenital cataracts (CC) are responsible for approximately one-tenth of childhood blindness cases globally. Here, we report an African American family with a recessively inherited form of CC. The proband demonstrated decreased visual acuity and bilateral cataracts, with nuclear and cortical cataracts in the right and left eye, respectively. Exome sequencing revealed a novel homozygous variant (c.563A > G; p.(Asn188Ser)) in GJA3, which was predicted to be pathogenic by structural analysis. Dominantly inherited variants in GJA3 are known to cause numerous types of cataracts in various populations. Our study represents the second case of recessive GJA3 allele, and the first report in African Americans. These results validate GJA3 as a bona fide gene for recessively inherited CC in humans.     

Surface behavior of blends of siloxane and siloxane-containing copolymers in poly(vinyl chloride)

X-ray photoelectron spectroscopy is used to reveal surface/bulk compositional relationships in blends of polydimethylsiloxane (PDMS) and PDMS/polycarbonate block copolymers in poly(vinyl chloride) (PVC). It is shown that the surface of PVC can be enriched in siloxane up to 60 at. % PDMS without visible indications of phase separation.     

Effect of active gas mixture composition on tribological behavior of coatings obtained by reactive magnetron sputtering of chromium in acetylene–nitrogen and acetylene–air gas mixtures

The tribological properties of chromium-based coatings deposited by reactive magnetron sputtering in argon–acetylene–nitrogen and argon–acetylene–air mixtures of different volume compositions have been studied. The coatings acquired in acetylene–nitrogen gas mixture have DLC structure and demonstrate high mechanical characteristics and low coefficient of friction values in dry friction. Although the coefficient of friction of these coatings has a tendency to decrease with the increasing nitrogen volume concentration in the mixture (until the values below 0.1 in dry friction in pair with silicon nitride), their performance diminishes at high contact pressures. This decrease was maximal for coatings deposited in acetylene–nitrogen gas mixture, with 80 vol % of nitrogen. The substitution of nitrogen with air is shown to considerably improve the performance, but a further increase in the air volume fraction above 85 vol % provokes a drastic decrease in the efficiency, especially at high contact pressures. The possible mechanisms of these effects and the abilities of their elimination are discussed, as well.     

A zeolite/polymer membrane for separation of ethanol-water azeotrope

A novel membrane effective in the separation of ethanol-water mixtures by pervaporation was made by combining zeolite NaA and poly(vinyl chloride) modified by 2-(2′-butoxyethoxy)ethyl thiolate. Under ambient conditions, a separation factor (α) of 29 and pervaporability (P) of 4 × 10^?4 g m^?1 h^?1 were obtained for the azeotropic mixture whereas, in the absence of zeolite, the respective values were 7 and 7 × 10^?5. A mechanism was proposed relating the preferential water transport at ≈? 50% zeolite content to an interfacial “phase” between the zeolite and the modified polymer.     

Behavior of the vorticity vector in a supersonic nonuniform swirl flow of a combustible gas behind a moving curvilinear shock or detonation wave

Expressions for components of the vorticity vector behind a curvilinear shock or detonation wave propagating in a supersonic nonuniform flow of a combustible gas are derived. Plane and axisymmetric gas flows are considered. The free stream in the general case is a vortex flow with a specified distribution of parameters. Formulas for the vorticity components in the plane of the flow for axisymmetric flows are found to have the same form as formulas for steady axisymmetric flows. As in the case of steady flows, the normal-to-wave component of vorticity is demonstrated to remain continuous across the discontinuity surface; in the case of axisymmetric flows, the ratio of the tangential component of vorticity aligned in the plane of the flow to density also remains continuous, though the quantities themselves become discontinuous. __________ Translated from Fizika Goreniya i Vzryva, Vol. 45, No. 2, pp. 68–75, March–April, 2008.     

Calculation of the parameters of pulsed laser welding of thin sheets of aluminium alloys

One of the main advantages of the MIG/MAG process is its high productivity. In most of the applications, positive polarity is used, due to its greater arc stability, generation of less splatter and formation of weld beads with suitable geometry. However, in some applications, there is a need for greater production capacity than that offered by conventional MIG/MAG welding. In the literature, it is stated that negative polarity provides a higher fusion rate than positive, despite leading to a high level of splatter and unsuitable formation of the weld bead. Unfortunately, there is not much information available on the effects of the process variables in this polarity, much less justification for such. Therefore, this work is an attempt to try to understand the reason why there is a higher deposit rate in negative polarity, as well as the related effect on the geometry of the weld beads. To do this, comparative MIG/MAG welds were produced in both positive and negative polarities, using two compositions of shielding gases at two current values. The transfer mode and the behaviour of the arc were analysed by synchronized profiling. The geometric profile of the weld bead was evaluated by means of metallographic procedures. From the results, which disagree in part with the current literature, it was seen that both the transfer mode as well as the morphology and the appearance of the weld bead are dependent on the composition of the shielding gas. To explain the phenomena inherent in the greater fusion rate of wire in DC ? , the suggestion is that the fact that arc scales the sides of the wire in this polarity may be the governing factor.     

First-level Dulkyn gravitational wave detector

The functional-block diagram of the Dulkyn gravitational wave detector is described.     

Simulation of scattering processes of optical radiation by nanodimensional structures

Mathematical simulation of the process of scattering of an optical wave by micro- or nano-scale structure on the basis of the vector equations of the electromagnetic field is performed. A rigorous analytic solution is obtained and the scattering problem solved by means of the method of finite elements.     

Perceived trustworthiness of knowledge sources: The moderating impact of relationship length.

Prior meta-analytic evidence has indicated no association between relationship length and perceived trustworthiness. Viewing trustors as information processors, the authors propose a model in which relationship length, although having no direct effect on perceived trustworthiness, moderates the association between perceived trustworthiness and the basis on which people decide to trust each other. Specifically, as trustors learn about others, they base their trust on different kinds of information (demographic similarity, trustworthy behavior, and shared perspective). Hierarchical multiple regression analyses of a field survey of supervisors and subordinates from 3 companies (N = 88) provide evidence consistent with this prediction: Perceived trustworthiness is associated with demographic similarity in newer relationships, with trustworthy behavior in relationships that are neither brand new nor old but in-between, and with shared perspective in older relationships. (PsycINFO Database Record (c) 2010 APA, all rights reserved)