Electrical injection of spin-polarized electrons into a semiconductor, large spin diffusion length, and an integration friendly platform are desirable ingredients for spin-based devices. Here we demonstrate lateral spin injection and detection in germanium nanowires, by using ferromagnetic metal contacts and tunnel barriers for contact resistance engineering. Using data measured from over 80 samples, we map out the contact resistance window for which lateral spin transport is observed, manifestly showing the conductivity matching required for spin injection. Our analysis, based on the spin diffusion theory, indicates that the spin diffusion length is larger than 100 mum in germanium nanowires at 4.2 K.

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Spectroscopic ellipsometry (SE) is applied to characterize Si columnar nanostructures. By employing effective medium approximation (EMA) theory, Si nanorods are treated as a graded layer with each sub‐layer modeled as a mixture of Si and voids with varying porosity fraction. In addition, the rigorous coupled‐wave analysis and finite‐element Green's function method were used in modeling Si nanorods as a stack of disks with varying diameters and thicknesses, and the calculations are in satisfactory agreement with the measurement results. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)

A B S T R A C TObjectives: Although the association between systemic infection and cardiovascular events has been identified, uncertainty remains regarding the incidence and prognosis of sepsis in acute myocardial infarction (AMI). The purpose of this research was to assess the impact of sepsis on survival after first AMI. Methods: This was a nationwide cohort study involving the analysis of data from the Taiwan National Health Insurance Research Database for the period 2000-2012, for patients with a primary diagnosis of first AMI. Among the 186 112 prospective patients, sepsis was diagnosed in 13 065 (7.0%). The propensity score matching technique was used to match 13 065 controls to the patients with sepsis and AMI with similar baseline characteristics. Cox proportional hazards regression models, including sepsis, percutaneous coronary intervention (PCI), and comorbidities, were performed to further evaluate the different influences on the mortality risk in patients hospitalized for first AMI. Results: Overall, the 12-year survival rate was lower in AMI patients with sepsis than in those without sepsis (log rank p-value <0.001); this was also shown in the different age and sex groups. The AMI patients with sepsis had a longer length of hospital stay than those without sepsis (32.5 days vs. 11.74 days, p < 0.001). In the Cox proportional hazards regression analysis, sepsis was an independent risk factor for mortality in patients after AMI (hazard ratio 1.78; 95% confidence interval 1.72-1.83). Interventional management with PCI or coronary artery bypass grafting improved survival in both the sepsis and non-sepsis patients after first AMI. Conclusions: In conclusion, sepsis significantly increased the mortality risk of patients after first AMI. PCI may improve the long-term survival of patients in comparison to those managed conservatively.

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