Physical activity and the risk of ischemic stroke: A population-based longitudinal follow-up study in Taiwan (KCIS no. 43).

Lack of exercise is a leading risk factor for stroke, and it has been demonstrated that increasing physical activity (PA) can prevent ischemic stroke. However, there has been limited research on the relationship between ischemic stroke and PA, especially among Asian populations. This study therefore investigates whether the level of PA in the Taiwanese population affects its risk of first-ever ischemic stroke, utilizing screening data on 58,857 individuals collected by the Keelung Health Bureau between 2005 and 2012. These subjects were divided into three groups based on their weekly exercise frequency and duration, i.e., 1) a no PA (NPA) group, 2) a low PA (LPA) group (less than 90 min of exercise per week), and 3) a high PA (HPA) group (90 min or more of exercise per week). The results showed that, as compared to the NPA group, the adjusted hazard ratio for ischemic stroke in the LPA group was 0.86 (95 % CI, 0.78-0.95, p < 0.0001); and that in the HPA group, it was also 0.86 (95 % CI, 0.79-0.94, p < 0.0001). In other words, even engaging in PA for less than 90 min per week may lower the risk of first-ever ischemic stroke. Importantly, LPA is more accessible, more sustainable, and easier to promote for the general population than the 150 min per week recommended by the World Health Organization.

A rating of perceived exertion scale using facial expressions for conveying exercise intensity for children and young adults.

OBJECTIVES: To design a rating of perceived exertion (RPE) scale using facial expressions and assessed the validity of the scale for both children and young adults. DESIGN: Pearson moment-product correlation analysis was used to assess the correlation among heart rate (HR), RPE and pedaling workload. METHODS: Fifteen children and 15 young adults participated in the study. Each participant randomly performed 5 pedaling tests with one repetition based on their submaximal acceptable workloads. Under each load condition, participants pedaled on a cycle ergometer for 10min; subsequently, participants completed Borg category ratio (CR10) or facial RPE (FRPE) scale assessments. Participants' heart rates (HR) were used to compare their scores on the Borg CR10 and Facial RPE scales. RESULTS: The results show that both Borg CR10 and FRPE scales reflected different pedaling workload levels. For young adults, HR positively correlated with both RPE scores under the various workload levels (r=0.989 and 0.977, all p<0.005); for children, only FRPE scores were positively correlated with HR (r=0.908, p<0.05). In other words, FRPE scores effectively reflected the HR of children, whereas Borg CR10 scores did not. CONCLUSIONS: The children may not understand words as effectively as young adults did, however, they understand facial expressions. The FRPE scale proposed in this study may be available in some special cases because it can assess those who cannot comprehend the written words used for the scale.

Mechanical Stability of Flexible Graphene-Based Displays.

The mechanical behavior of a prototype touch panel display, which consists of two layers of CVD graphene embedded into PET films, is investigated in tension and under contact-stress dynamic loading. In both cases, laser Raman spectroscopy was employed to assess the stress transfer efficiency of the embedded graphene layers. The tensile behavior was found to be governed by the "island-like" microstructure of the CVD graphene, and the stress transfer efficiency was dependent on the size of graphene "islands" but also on the yielding behavior of PET at relatively high strains. Finally, the fatigue tests, which simulate real operation conditions, showed that the maximum temperature gradient developed at the point of "finger" contact after 80 000 cycles does not exceed the glass transition temperature of the PET matrix. The effect of these results on future product development and the design of new graphene-based displays are discussed.

Deformation of wrinkled graphene.

The deformation of monolayer graphene, produced by chemical vapor deposition (CVD), on a polyester film substrate has been investigated through the use of Raman spectroscopy. It has been found that the microstructure of the CVD graphene consists of a hexagonal array of islands of flat monolayer graphene separated by wrinkled material. During deformation, it was found that the rate of shift of the Raman 2D band wavenumber per unit strain was less than 25% of that of flat flakes of mechanically exfoliated graphene, whereas the rate of band broadening per unit strain was about 75% of that of the exfoliated material. This unusual deformation behavior has been modeled in terms of mechanically isolated graphene islands separated by the graphene wrinkles, with the strain distribution in each graphene island determined using shear lag analysis. The effect of the size and position of the Raman laser beam spot has also been incorporated in the model. The predictions fit well with the behavior observed experimentally for the Raman band shifts and broadening of the wrinkled CVD graphene. The effect of wrinkles upon the efficiency of graphene to reinforce nanocomposites is also discussed.

The cell end marker Tea4 regulates morphogenesis and pathogenicity in the basidiomycete fungus Ustilago maydis.

Positional cues localized to distinct cell domains are critical for the generation of cell polarity and cell morphogenesis. These cues lead to assembly of protein complexes that organize the cytoskeleton resulting in delivery of vesicles to sites of polarized growth. Tea4, an SH3 domain protein, was first identified in fission yeast, and is a critical determinant of the axis of polarized growth, a role conserved among ascomycete fungi. Ustilago maydis is a badiomycete fungus that exhibits a yeast-like form that is nonpathogenic and a filamentous form that is pathogenic on maize and teozintle. We are interested in understanding how positional cues contribute to generation and maintenance of these two forms, and their role in pathogenicity. We identified a homologue of fission yeast tea4 in a genetic screen for mutants with altered colony and cell morphology and present here analysis of Tea4 for the first time in a basidiomycete fungus. We demonstrate that Tea4 is an important positional marker for polarized growth and septum location in both forms. We uncover roles for Tea4 in maintenance of cell and neck width, cell separation, and cell wall deposition in the yeast-like form, and in growth rate, formation of retraction septa, growth reversal, and inhibition of budding in the filamentous form. We show that Tea4::GFP localizes to sites of polarized or potential polarized growth in both forms, as observed in ascomycete fungi. We demonstrate an essential role of Tea4 in pathogencity in the absence of cell fusion. Basidiomycete and ascomycete Tea4 homologues share SH3 and Glc7 domains. Tea4 in basidiomycetes has additional domains, which has led us to hypothesize that Tea4 has novel functions in this group of fungi.

Thermal properties of graphene-copper-graphene heterogeneous films.

We demonstrated experimentally that graphene-Cu-graphene heterogeneous films reveal strongly enhanced thermal conductivity as compared to the reference Cu and annealed Cu films. Chemical vapor deposition of a single atomic plane of graphene on both sides of 9 µm thick Cu films increases their thermal conductivity by up to 24% near room temperature. Interestingly, the observed improvement of thermal properties of graphene-Cu-graphene heterofilms results primarily from the changes in Cu morphology during graphene deposition rather than from graphene's action as an additional heat conducting channel. Enhancement of thermal properties of graphene-capped Cu films is important for thermal management of advanced electronic chips and proposed applications of graphene in the hybrid graphene-Cu interconnect hierarchies.

Fuz1, a MYND domain protein, is required for cell morphogenesis in Ustilago maydis.

Abstract: Ustilago maydis is a Basidiomycete fungus that exhibits a yeast-like nonpathogenic form and a dikaryotic filamentous pathogenic form. Generation of these two forms is controlled by two mating type loci, a and b. The fungus undergoes additional morphological transitions in the plant that result in formation of a third cell type, the teliospore. The fuz1 gene is necessary for this developmental program. Here we report cloning and sequencing of fuz1 and show that it contains an open reading frame with coding capacity for a protein of 1421 amino acids. The Fuz1 protein belongs to the family of MYND Zn finger domain proteins. We generate a null mutation in strains of opposite mating type and show that fuz1 is necessary for conjugation tube formation, a morphological transition that occurs in response to pheromones. We generate fuz1- diploid strains heterozygous at a and b and show that fuz1 is also necessary for postfusion events (maintenance of filamentous growth). We also demonstrate that fuz1 is necessary for cell morphogenesis of the yeast-like cell: normal cell length, location and number of septa, cell separation and constriction of the neck region. Fuz1 is also required for cell wall integrity and to prevent secretion of a dark pigment. We propose that the MYND domain may interact with different proteins to regulate cell morphogenesis.