Publications by authors named "Victor Lange"

Hexagonal Si Ge with suitable alloy composition promises to become a new silicon compatible direct bandgap family of semiconductors. Theoretical calculations, however, predict that the binary end point of this family, the bulk hex-Ge crystal, is only weakly dipole active. This is in contrast to hex-Si Ge , where translation symmetry is broken by alloy disorder, permitting efficient light emission.

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Silicon is indisputably the most advanced material for scalable electronics, but it is a poor choice as a light source for photonic applications, due to its indirect band gap. The recently developed hexagonal SiGe semiconductor features a direct bandgap at least for x > 0.65, and the realization of quantum heterostructures would unlock new opportunities for advanced optoelectronic devices based on the SiGe system.

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Monolithic integration of silicon-based electronics and photonics could open the door toward many opportunities including on-chip optical data communication and large-scale application of light-based sensing devices in healthcare and automotive; by some, it is considered the Holy Grail of silicon photonics. The monolithic integration is, however, severely hampered by the inability of Si to efficiently emit light. Recently, important progress has been made by the demonstration of efficient light emission from direct-bandgap hexagonal SiGe (hex-SiGe) alloy nanowires.

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Introduction: Forced-air warming (FAW) is a commonly used method of patient warming to reduce perioperative hypothermia and minimize associated surgical complications.

Objectives: The primary objective of this study was to demonstrate even when properly managed, FAW units may contribute to greater environmental bacterial load and infection risk.

Methods: A study conducted in 2018 revealed that FAW contamination occurs more than expected in the surgical environment.

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Silicon crystallized in the usual cubic (diamond) lattice structure has dominated the electronics industry for more than half a century. However, cubic silicon (Si), germanium (Ge) and SiGe alloys are all indirect-bandgap semiconductors that cannot emit light efficiently. The goal of achieving efficient light emission from group-IV materials in silicon technology has been elusive for decades.

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Background: Investigation into personal health has become focused on conditions at an increasingly local level, while response rates have declined and complicated the process of collecting data at an individual level. Simultaneously, social media data have exploded in availability and have been shown to correlate with the prevalence of certain health conditions.

Objective: Facebook likes may be a source of digital data that can complement traditional public health surveillance systems and provide data at a local level.

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We investigated eyewear contamination levels in the operating room to assess infection risk and inform protocol development. Microbial contamination after use was found in 37.7% of disposable and 94.

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