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We report a dramatic size effect on the morphology of Ge nanowires synthesized by low-temperature vapor-solid-solid (VSS) growth using a NiGe catalyst. Nanowires with diameter greater than 25 nm are <111>-oriented, have a high density of grown-in defects, and exhibit frequent kinking. However, nanowires with diameter below 25 nm are straight, despite also having a substantial density of crystal defects. The latter wires grow preferentially in the <110> direction. The absence of kinking in the small nanowires coincides with the observation of a low-energy, epitaxial NiGe/Ge interface. Our results show that the occurrence of (1) this solid-solid epitaxial interface and (2) the low-energy sidewall facets of the <110> wire orientation strongly bias the Ni-Ge binary system toward kink-free nanowire growth in the VSS regime. We further demonstrate that kinking in larger nanowires occurs via multiple twinning events facilitated by the slow growth and anisotropic catalyst/wire interfaces typical of VSS growth. Such effects are expected in other VSS systems where a range of nanowire morphologies are observed. [ABSTRACT FROM AUTHOR]

TiO2/Al2O3/Ge gate stacks have promising characteristics for future germanium-channel high-performance MOSFETs. In this letter, TiO2/Al2O3 bilayer high-k dielectrics with EOT 0.65 nm are demonstrated and used in Ge pMOSFETs for the first time, giving low subthreshold swing (71 mV/dec) and large on-state current (28 A/um). In addition, detailed investigations of these devices with two different gate metals - Al/W and Al/Pt - are performed for stable metal/TiO2 interfaces and EOT scaling. [ABSTRACT FROM AUTHOR]

Background: Genital Tuberculosis is a form of extrapulmonary tuberculosis, which if not diagnosed early can lead to complications. The objective of this study was to determine the sensitivity and specificity of Xpert Mycobacterium tuberculosis/rifampin (MTB/RIF) assay in genital tuberculosis (TB) in comparison with culture as a gold standard., Methods: The results of the Xpert MTB/RIF assay performed from January 2020 to August 2021 were compared with the results of culture by Mycobacterium Growth Indicator Tube (MGIT) 960., Results: Out of 75 specimens, fluorescent microscopy and liquid culture using MGIT and Xpert assay were positive in 3 (4%), 21 (28%), and 14 (18%), respectively. The sensitivity and specificity of the Xpert MTB/RIF assay were 66.67% and 100%. All smear-positive specimens were positive by culture and Xpert assay. Three specimens were positive by all the tests, i.e., microscopy, culture, and Xpert assay. Fifty-four specimens were negative by microscopy, culture, and Xpert assay. Discordance between the results of culture and Xpert assay was observed in seven specimens which were culture positive and Xpert assay negative. Three (21.42%) out of 21 culture-positive specimens showed monoresistance to rifampicin by Xpert MTB/RIF assay and culture drug susceptibility testing., Conclusion: Xpert MTB/RIF assay showed good sensitivity and specificity compared to liquid culture in genital TB. This test is easy to perform, provides results in 2 h, and can also detect rifampicin resistance, which is a surrogate marker for multidrug-resistant TB. Hence, the Xpert assay can be used under the National TB Elimination Program for early and rapid diagnosis of TB in endometrial specimens to prevent complications like infertility., Competing Interests: None

Behaviors are inextricably linked to internal state. We have identified a neural mechanism that links female sexual behavior with the estrus, the ovulatory phase of the estrous cycle. We find that progesterone-receptor (PR)-expressing neurons in the ventromedial hypothalamus (VMH) are active and required during this behavior. Activating these neurons, however, does not elicit sexual behavior in non-estrus females. We show that projections of PR+ VMH neurons to the anteroventral periventricular (AVPV) nucleus change across the 5-day mouse estrous cycle, with ∼3-fold more termini and functional connections during estrus. This cyclic increase in connectivity is found in adult females, but not males, and regulated by estrogen signaling in PR+ VMH neurons. We further show that these connections are essential for sexual behavior in receptive females. Thus, estrogen-regulated structural plasticity of behaviorally salient connections in the adult female brain links sexual behavior to the estrus phase of the estrous cycle., (Copyright © 2019 Elsevier Inc. All rights reserved.)