Diagnosis of tuberculous spondylitis

Diagnosis of tuberculous spondylitis in adults, especially in the absence of kyphosis and a characteristic response to the load of the spine, is often very difficult. Barr (Bulk md., No. 10, 1923) advises in such cases to pay special attention to various "neuralgic" phenomena, unilateral increase in tendon reflexes and Babinsk'oro symptom, as well as to limited rigidity of the spinal muscles.

Chemical separation of acrylic color components enabling the identification of the pigment spectroscopic response

Acrylic colors are mixtures of several components that can be identified as pigments, binders, and fillers, so that, when analyzed, the characteristic response of the different components may not be recognizable. This limits the accuracy of spectroscopic techniques, nonetheless particularly useful as they are noninvasive and can be applied in situ on real artworks. Here, a method is proposed to chemically separate and identify the different components of acrylic colors, in order to be able to study their spectroscopic response separately, in particular by ultraviolet–visible–near-infrared diffuse reflectance. The results clearly show that the chemical and analytical method developed here is fully reliable, with the advantage of clearly separating the response of the different components without any change of their chromatic/chemical properties. As a case study, the new method is applied here to original acrylic colors used by the Italian artist Ico Parisi, in view of building a spectra database.

The characteristic response of domestic cats to plant iridoids allows them to gain chemical defense against mosquitoes

Domestic cats and other felids rub their faces and heads against catnip (Nepeta cataria) and silver vine (Actinidia polygama) and roll on the ground as a characteristic response. While this response is well known, its biological function and underlying mechanism remain undetermined. Here, we uncover the neurophysiological mechanism and functional outcome of this feline response. We found that the iridoid nepetalactol is the major component of silver vine that elicits this potent response in cats and other felids. Nepetalactol increased plasma β-endorphin levels in cats, while pharmacological inhibition of μ-opioid receptors suppressed the classic rubbing response. Rubbing behavior transfers nepetalactol onto the faces and heads of respondents where it repels the mosquito, Aedes albopictus. Thus, self-anointing behavior helps to protect cats against mosquito bites. The characteristic response of cats to nepetalactol via the μ-opioid system provides an important example of chemical pest defense using plant metabolites in nonhuman mammals.

Исследования фоточувствительности узкозонных и бесщелевых твердых растворов HgCdTe в терагерцовом и субтерагерцовом диапазоне частот

The photoresponse is investigated in the frequency range of 0.15–15 THz in HgCdTe epitaxial layers with a cadmium concentration from 15.2 to 19.2% grown by molecular-beam epitaxy. It is shown that narrow-gap and gapless HgCdTe solid solutions can be used as detectors of both terahertz and sub-terahertz radiation with a characteristic response time of 2–4 ns and with a sensitivity approaching n -InSb-based detectors widely used in this range.