Clinical breakage, slippage and acceptability of two commercial ultra-thin polyurethane male condoms compared to a commercial thin latex condom: a randomised, masked, 3 way crossover, multi centre controlled study (SAGCS 2).

Background: Although natural rubber latex remains dominant as the primary manufacturing material for male condoms synthetic materials first introduced in the early 1990s address many of the limitations of latex including the risk of allergies. Polyurethane elastomers allow condoms to be made significantly thinner to provide greater sensitivity and encourage greater use of condoms for contraception and STI prophylaxis. The primary objective of this Study was to evaluate the breakage, slippage and acceptability of two ultra-thin polyurethane condoms against a thin control latex male condom, designated latex C, in a randomized, cross over, masked, non-inferiority study.

Large-area periodically-poled lithium niobate wafer stacks optimized for high-energy narrowband terahertz generation.

Periodically-poled lithium niobate (PPLN) sources consisting of custom-built stacks of large-area wafers provide a unique opportunity to systematically study the multi-cycle terahertz (THz) generation mechanism as they are assembled layer-by-layer. Here we investigate and optimize the THz emission from PPLN wafer stacks as a function of wafer number, pump fluence, pulse duration and chirp, wafer separation, and pump focusing. Using 135 µm-thick, 2"-diameter wafers we generate high-energy, narrowband THz pulses with central frequencies up to 0.

No interface energy barrier and increased surface pinning in low temperature baked niobium.

Superconducting Radio-Frequency cavities are currently made out of niobium. Niobium cavities are limited by the magnetic field on the cavity walls due to the entry of vortices at the field of first vortex penetration, H[Formula: see text]. Low temperature baking in vacuum or low pressure gas atmosphere removes the strong decrease of the quality factor with accelerating gradient (high field Q-slope).

Surveying the Challenges to Improve Linear Accelerator-based Radiation Therapy in Africa: a Unique Collaborative Platform of All 28 African Countries Offering Such Treatment.

Radiation therapy is a critical component for curative and palliative treatment of cancer and is used in more than half of all patients with cancer. Yet there is a global shortage of access to this treatment, especially in Sub-Saharan Africa, where there is a shortage of technical staff as well as equipment. Linear accelerators (LINACs) offer state-of-the-art treatment, but this technology is expensive to acquire, operate and service, especially for low- and middle-income countries (LMICs), and often their harsh environment negatively affects the performance of LINACs, causing downtime.