Publications

Radial core/shell nanowires (NWs) represent an important class of nanoscale building blocks with substantial potential for exploring fundamental electronic properties and realizing novel device applications at the nanoscale. Here, we report the synthesis of crystalline silicon/amorphous silicon (Si/a-Si) core/shell NWs and studies of crossed Si/a-Si NW metal NW (Si/a-Si × M) devices and arrays. Room-temperature electrical measurements on single Si/a-Si × Ag NW devices exhibit bistable switching between high (off) and low (on) resistance states with well-defined switching threshold voltages, on/off ratios greater than 104, and current rectification in the on state. Temperature-dependent switching experiments suggest that rectification can be attributed to barriers to electric field-driven metal diffusion. Systematic studies of Si/a-Si × Ag NW devices show that (i) the bit size can be at least as small as 20 nm × 20 nm, (ii) the writing time is <100 ns, (iii) the retention time is >2 weeks, and (iv) devices can be switched >104 times without degradation in performance. In addition, studies of dense one-dimensional and two-dimensional Si/a-Si × Ag NW devices arrays fabricated on crystalline and plastic substrates show that elements within the arrays can be independently switched and read, and moreover that bends with radii of curvature as small as 0.3 cm cause little change in device characteristics. The Si/a-Si × Ag NW devices represent a highly scalable and promising nanodevice element for assembly and fabrication of dense nonvolatile memory and programmable nanoprocessors.

Additional file 12: Table S10. Results of functional enrichment analyses using genes linked to the CpGs with p-values &lt; 1-x10-4 in each of the models using Gene Ontology (GO) terms or Kyoto Encyclopedia of Genes and Genomes (KEGG) terms (FDR &lt;0.05).

Background The previously validated Healthy Heart Score effectively predicted the 20‐year risk of cardiovascular disease (CVD). We examine whether the Healthy Heart Score may extend to an association with total and cause‐specific mortality. Methods and results The prospective cohort study investigated 58 319 women (mean age 50.2 years) in the Nurses’ Health Study (1984–2010) and 29 854 in men (mean age 52.7 years) in the Health Professionals’ Follow‐up Study (1986–2010) free of cancer and CVD at baseline. The Healthy Heart Score included baseline current smoking; high body mass index; low physical activity; no or excessive alcohol intake; low intake of fruits and vegetables, cereal fiber, or nuts; and high intake of sugar‐sweetened beverages or red/processed meats. There were 19 122 total deaths. Compared with participants in the first quintile of the Healthy Heart Score (lowest CVD risk), participants in the fifth quintile (highest CVD risk) had a pooled hazard ratio of 2.26 (95% confidence interval [CI], 1.53–3.33) for total mortality; 2.85 (95 % CI, 1.92–4.23) for CVD mortality, and 2.14 (95% CI, 1.56–2.95) for cancer mortality. Participants in the fifth versus the first quintile also had significantly greater risk of death due to coronary heart disease (3.37; 95% CI, 2.16–5.25), stroke (1.75; 95% CI, 1.02–2.99), lung cancer (6.04; 95% CI, 2.78–13.13), breast cancer (1.45; 95% CI, 1.14–1.86), and colon cancer (1.51; 95% CI, 1.18–1.93). Conclusions The Healthy Heart Score, composed of 9 self‐reported, modifiable lifestyle predictors of CVD, is a potentially useful tool for the counseling of healthy lifestyles that was strongly associated with greater risk of all‐cause, CVD, and cancer mortality.

Endothelial cell spreading is mediated by the extracellular matrix (ECM), and it is the thought to be regulated by the binding of integrin receptors and the associated focal adhesions (FA). In the present study, we examined the relationship between FA formation and endothelial cell shape changes using microfabricated substrates patterned with islands of immobilized fibronectin (FN) surrounded by nonadhesive borders to control the degree of cell spreading. The amount of FA formation, as detected by the localized presence of vinculin and phosphotyrosine, increased in direct proportion to the degree of cell spreading. To determine whether the observed increase in FA formation was a direct result of more fibronectin in contact with spread cells, single cells were spread across multiple subcellular sized islands such that the size and spacing of the islands could vary cell spreading independently from the amount of cell-ECM contact. We found that total FA increased with cell spreading, regardless of the amount of ECM in contact with cells. The FAs formed on these substrates developed a structural directionality and quantity which correlated to the direction and magnitude of tensional stress in the actin cytoskeleton. Thus, global changes in cell shape regulate the local cytoskeletal tensions that drives FA formation.

An intuitive graphical interface that allows statistical analyses and visualizations of extensive data without any knowledge of dedicated statistical software or programming.EpiMetal is a single-page web application written in JavaScript, to be used via a modern desktop web browser.Standard epidemiological analyses and self-organizing maps for data-driven metabolic profiling are included. Multiple extensive datasets with an arbitrary number of continuous and category variables can be integrated with the software. Any snapshot of the analyses can be saved and shared with others via a www-link. We demonstrate the usage of EpiMetal using pilot data with over 500 quantitative molecular measures for each sample as well as in two large-scale epidemiological cohorts (N >10 000).The software usage exemplar and the pilot data are open access online at [http://EpiMetal.computationalmedicine.fi]. MIT licensed source code is available at the Github repository at [https://github.com/amergin/epimetal].

Submicrometer patterns of glasses on a substrate have been created using a type of soft lithography. The method, which is complementary to photolithography and rapid ion etching, is described and examples of applications are given. The Figure shows a scanning electron micrograph of a membrane of titanosilicate glass after an aqueous suspension of 2 μm beads had passed through it.

An investigation of asymptotic crack tip singular fields and their domain of validity is carried out for mode I cracks in solids characterized by the phenomenological strain gradient plasticity theory proposed by Fleck NA, Hutchinson JW. (Strain gradient plasticity. In: Hutchinson JW, Wu TY, editors. Advances in applied mechanics, vol. 33. New York: Academic Press, 1997. pp. 295–361.) Separable near-tip singular fields are determined where fields quantities depend on the radial and circumferential coordinates (r,θ) according to rpf θ . The singular field is completely dominated by the strain gradient contributions to the constitutive law. In addition to the asymptotic analysis, full field numerical solutions are obtained by a finite element method using elements especially suited to the higher order theory. It is found that the singular field provides a numerically accurate representation of the full field solution only within a distance from the tip that is a tiny fraction of the constitutive length parameter. The constitutive theory itself is not expected to be valid in this domain. Curiously, the normal traction acting across the extended crack line ahead of the crack tip is found to be compressive in the singular field. The conclusion which must be drawn is that the singular field has a tiny domain of mathematical validity (neglecting crack face interaction), but no domain of physical validity. The significant elevation of tractions ahead of the crack tip due to strain gradient hardening occurs at distances from the crack tip which are well outside this tiny domain in a region where the plasticity theory is expected to be applicable. The asymptotic singular fields are incapable of capturing the effect of traction elevation.

Background: There are various maternal prenatal biopsychosocial (BPS) predictors of birth weight, making it difficult to quantify their cumulative relationship. Methods: We studied two birth cohorts: Northern Finland Birth Cohort 1986 (NFBC1986) born in 1985-1986 and the Generation R Study (from the Netherlands) born in 2002-2006. In NFBC1986, we selected variables depicting BPS exposure in association with birth weight and performed factor analysis to derive latent constructs representing the relationship between these variables. In Generation R, the same factors were generated weighted by loadings of NFBC1986. Factor scores from each factor were then allocated into tertiles and added together to calculate a cumulative BPS score. In all cases, we used regression analyses to explore the relationship with birth weight corrected for sex and gestational age and additionally adjusted for other factors. Results: Factor analysis supported a four-factor structure, labelled closely to represent their characteristics as â € Factor1-BMI' (body mass index), â € Factor2-DBP' (diastolic blood pressure), â € Factor3-Socioeconomic-Obstetric-Profile' and â € Factor4-Parental-Lifestyle'. In both cohorts, â € Factor1-BMI' was positively associated with birth weight, whereas other factors showed negative association. â € Factor3-Socioeconomic-Obstetric-Profile' and â € Factor4-Parental-Lifestyle' had the greatest effect size, explaining 30% of the variation in birth weight. Associations of the factors with birth weight were largely driven by â € Factor1-BMI'. Graded decrease in birth weight was observed with increasing cumulative BPS score, jointly evaluating four factors in both cohorts. Conclusion: Our study is a proof of concept for maternal prenatal BPS hypothesis, highlighting the components snowball effect on birth weight in two different European birth cohorts.