Genetic and environmental influences on predictors of decline in daily functioning, including forced expiratory volume in 1 s (FEV1), forced vital capacity (FVC), handgrip, and five-times-sit-to-stand test (FTSST), have not been addressed in the aging Chinese population. We performed classical twin modeling on FEV1, FVC, handgrip, and FTSST in 379 twin pairs (240 MZ and 139 DZ) with median age of 50 years (40–80 years). Data were analyzed by fitting univariate and bivariate twin models to estimate the genetic and environmental influences on these measures of physical function. Heritability was moderate for FEV1, handgrip, and FTSST (55–60%) but insignificant for FVC. Only FVC showed moderate control, with shared environmental factors accounting for about 50% of the total variance. In contrast, all measures of pulmonary function and muscle strength showed modest influences from the unique environment (40–50%). Bivariate analysis showed highly positive genetic correlations between FEV1 and FVC (rG = 1.00), and moderately negative genetic correlations between FTSST and FEV1 (rG = −0.33) and FVC (rG = −0.42). FEV1 and FVC, as well as FEV1 and handgrip, displayed high common environmental correlations (rC = 1.00), and there were moderate correlations between FVC and handgrip (rC = 0.44). FEV1 and FVC showed high unique environmental correlations (rE = 0.76) and low correlations between handgrip and FEV1 (rE = 0.17), FVC (rE = 0.14), and FTSST (rE = −0.13) with positive or negative direction. We conclude that genetic factors contribute significantly to the individual differences in common indicators of daily functioning (FEV1, handgrip, and FTSST). FEV1 and FVC were genetically and environmentally correlated. Pulmonary function and FTSST may share similar sets of genes but in the negative direction. Pulmonary function and muscle strength may have a shared environmental background.

The genetic influences on aging-related phenotypes, including cognition and depression, have been well confirmed in the Western populations. We performed the first twin-based analysis on cognitive performance, memory and depression status in middle-aged and elderly Chinese twins, representing the world's largest and most rapidly aging population. The sample consisted of 384 twin pairs with a median age of 50 years. Cognitive function was measured using the Montreal Cognitive Assessment (MoCA) scale; memory was assessed using the revised Wechsler Adult Intelligence scale; depression symptomatology was evaluated by the self-reported 30-item Geriatric Depression (GDS-30)scale. Both univariate and multivariate twin models were fitted to the three phenotypes with full and nested models and compared to select the best fitting models. Univariate analysis showed moderate-to-high genetic influences with heritability 0.44 for cognition and 0.56 for memory. Multivariate analysis by the reduced Cholesky model estimated significant genetic (rG = 0.69) and unique environmental (rE = 0.25) correlation between cognitive ability and memory. The model also estimated weak but significant inverse genetic correlation for depression with cognition (-0.31) and memory (-0.28). No significant unique environmental correlation was found for depression with other two phenotypes. In conclusion, there can be a common genetic architecture for cognitive ability and memory that weakly correlates with depression symptomatology, but in the opposite direction.

Stability and transparency are two critical indices of bilateral teleoperation systems. The wave variable method is a conservative approach to robustly guarantee system passivity under arbitrary constant time delays. However, the wave-variable-based reflection is an intrinsic problem in this method because it can significantly degrade system transparency and disorient the operator's perception of the remote environment. In order to enhance both the transparency and the stability of bilateral teleoperation systems in the presence of large time delays, a new four-channel (4-CH) architecture is proposed which applies two modified wave-transformation controllers to reduce wave-based reflections. Transparency and stability of the proposed system are analyzed and the improvement in these when using this method is measured experimentally. Results clearly demonstrate that the proposed method can produce high transparency and stability even in the presence of large time delays.

We evaluated the genetic and environmental contributions to metabolic cardiovascular risk factors and their mutual associations. Eight metabolic factors (body mass index, waist circumference, waist-to-hip ratio, systolic blood pressure, diastolic blood pressure, total serum cholesterol, serum triglycerides, and serum uric acid) were measured in 508 twin pairs aged 8–17 years from the Qingdao Twin Registry, China. Linear structural equation models were used to estimate the heritability of these traits, as well as the genetic and environmental correlations between them. Among boys, body mass index and uric acid showed consistently high heritability (0.49–0.81), whereas other traits showed moderate to high common environmental variance (0.37–0.73) in children (8–12 years) and adolescents (13–17 years) except total cholesterol. For girls, moderate to high heritability (0.39–0.75) were obtained for six metabolic traits in children, while only two traits showed high heritability and others mostly medium to large common environmental variance in adolescents. Genetic correlations between the traits were strong in both boys and girls in children (rg = 0.64–0.99 between body mass index and diastolic blood pressure; rg = 0.71–1.00 between body mass index and waist circumference), but decreased for adolescent girls (rg = 0.51 between body mass index and waist-to-hip ratio; rg = 0.55 between body mass index and uric acid; rg = 0.61 between body mass index and systolic blood pressure). The effect of genetic factors on most metabolic traits decreased from childhood to adolescence. Both common genetic and specific environmental factors influence the mutual associations among most of the metabolic traits.

Organized nanostructures are formed after irradiation of layers of randomly aligned single-wall carbon nanotube (SWNT)-polymer composites by a Ti:Sapphire 775 nm laser with a 150 fs pulse at fluences near 0.1 J/cm2. At varying peak fluences morphology is seen where the tubes are ejected from the substrate or formed into long, parallel structures of SWNT’s. These structures have been created on both glass substrates and carbon grids. Transmission Electron Microscopy (TEM) and Scanning Electron Microscopy (SEM) investigation of the structures reveal that they are composed of bundled nanotubes typically 400 nm – 1 micron long. Large-area laser patterning of the film allows for structuring of the film without detrimental decreases in conductivity.

The purpose of the present study was to evaluate the effects of serum-starvation, contact-inhibition and roscovitine treatments on cell-cycle synchronization at the G0/G1 stage of ear skin fibroblasts isolated from transgenic cloned cattle. The developmental competence of re-cloned embryos was also examined. Our results showed that the proportion of G0/G1 cells from the serum-starved group at 3, 4 or 5 days was significantly higher compared with 1 or 2 days only (91.5, 91.7 and 93.5% versus 90.1 and 88.8%, respectively, p < 0.05); whilst there was no statistical difference among cells at 3, 4 or 5 days. For roscovitine-treated cells, the proportion of G0/G1 cells at 2, 3, 4 or 5 days was significantly higher than those treated for 1 day only (91.1, 90.1, 89.4 and 91.3% versus 86.51%, respectively, p < 0.05). The proportion of contact-inhibited G0/G1 cells rose significantly with treatment time, but was similar at 3, 4 and 5 days (89.4, 90.4, 91.4, 91.6 and 92.1%, respectively, p < 0.05). The efficiency of obtaining G0/G1 phase cells was lower when roscovitine treatment was employed to synchronize the cell cycle compared with the serum-starvation and contact-inhibition methods (89.7 versus 91.1% and 91.0%, p < 0.05). Moreover, obvious differences were observed in the rate of fused couplets and blastocysts (89.88 ± 2.70 versus 87.40 ± 5.13; 44.10 ± 8.62 versus 58.38 ± 13.28, respectively, p < 0.05), when nuclear transfer embryos were reconstructed using donors cells that had been serum starved or contact inhibited for 3 days. Our data indicate that 3 day treatment is feasible for harvesting sufficient G0/G1 cells to produce re-cloned transgenic bovine embryos, regardless of whether serum-starvation, contact-inhibition or roscovitine treatments are used as the synchronization methods.

When exposed to air at room temperature, Zn nanoparticles oxidize gradually to form crystalline ZnO shells with a thickness of a few nanometers. Electron diffraction and high-resolution lattice imaging revealed that the ZnO layer on the Zn {0001} surface is composed of many epitaxial domains with small rotation angles relative to the lattice of the Zn core. The oxidized Zn particle bends when irradiated by the electron beam in a transmission electron microscope. This is due to the increase of internal stress in the ZnO layer as a result of the realignment of adjacent domains under electron beam irradiation. Corrosion of Zn nanoparticles was observed and the scaling and spalling start to occur on the {1010} prismatic faces.

A cell-free mRNA decay assay has been adapted to permit the kinetics of 3′ → 5′ exoribonuclease activities to be monitored in real time. RNA probes containing 5′ caps and 3′ poly(A) tails generated by transcription in vitro are 3′ labeled using fluorescein-N6-ATP and poly(A) polymerase. Release of fluorescein-conjugated adenosine residues from the 3′ end of the RNA substrate is monitored by a time-dependent decrease in fluorescence anisotropy in the presence of cytosolic proteins. To demonstrate the utility of the assay, an RNA probe was constructed containing a fragment of the c-myc 3′ untranslated region and an 85-base poly(A) tail. Following 3′ fluorescein labeling, the rate of 3′-terminal adenosine excision was monitored in the presence of an S100 cytosolic extract prepared from K562 erythroleukemia cells. Removal of the fluorescein-tagged A residues resolved to a first-order decay function, allowing the rate constant and enzyme-specific activity to be determined in this extract. Further applications and advantages of this technology are discussed.

Monodisperse hematite cubes about 30nm in size have been prepared by aging a refluxing acidified aqueous solution of FeCl3 in an open vessel. The as grown nano cubes were determined to be single crystalline hematite in perfect cubic shapes using transmission electron microscope and electron diffraction. The nano cube is one of the equilibrium shapes of hematite, which is resumed to be formed by preferential growth in certain crystallographic directions through the species diffusion in the aqueous solutions.

Some self-assembly prototypes have been observed, such as the short range ordered buildup consisting of several brick-like hematite nano cubes and the nano box consisted of square plates of hematite nanocrystals. The drive force for the formation of the above assemblies is assumed to be the unique magnetic feature of the single crystalline hematite nano cubes.

The perfect shape and the self-assembly feature give a possibility to fabricate bulk ceramics orderly assembled using hematite nano cubes.

Gallium nitride and its alloys are the most promising materials for short wave light emitters. If high quality GaN single crystals can be prepared, the GaN base light emitters should be fabricated directly on the lattice-matched GaN substrate.

In this work, GaN crystals in nano and micro scale with definite faces have been prepared by dc arc discharge using gallium and N2+NH3 as starting materials. Transmission electron microscope, selected area diffraction, x-ray microanalysis of energy dispersive spectroscopy, and x-ray diffraction investigation of the as grown GaN crystals show that the well faceted crystals are single crystalline GaN in wurtzite structure having lattice constants a0=3.18Å and c0=5.18Å. The crystal size of stoichoimetric GaN in wurtzite structure depends on the partial pressure of nitrogen in the plasma. The maximum crystal size in this work is about several micrometers.