Pharmacological action of anabolic steroids

Anabolic steroids (AS) are derivatives of androgen (testosterone and its close relatives). AS have been primarily developed for clinical use as anabolic agents with the expectation that they would be relatively less androgenic than testosterone and its close relatives. Various AS are applied to clinical use, but none is free from androgenic activity. Relation between chemical structure and anabolic-androgenic potency of various AS is summarized. AS action in erythropoiesis operates through increased porphyrin formation and production of erythropoietin. Mechanism of AS action in bone formation is suggested that AS potentiate intestinal 1.25(OH)2D receptors. Identification of androgen receptors in normal human osteoblast-like cells suggest that AS act directly on receptor-mediated mechanism. The other action of AS is briefly summarized.     

Digital implementation of bus clamped space vector modulation

Space vector modulation has recently become a popular PWM method of supplying a high performance drive. An adaptation of SVM modulation is presented here. This system is called bus clamped space vector modulation. This method has some practical advantages when compared to normal SVM. These include a reduced average switching frequency, easy digital implementation and asynchronous control and switching frequencies     

Frequency control techniques in coherent multichannel LAN's

This paper describes frequency control techniques for cold start and channel recognition functions in coherent multichannel local area networks. A Z-cut quartz etalon can be used to stabilize the optical transmitter frequencies. The capture range and the influence of humidity on a Fabry-Perot etalon are discussed. The frequency deviation of the optical transmitter was estimated to be less than ±1 GHz in the long term. A double AFC loop has been proposed for local LD frequency control. It showed a wide capture range of ±100 GHz. Coherent FDM receiver switching to the desired channel was demonstrated over a range from 0 to 40°C in an experiment     

Ultrasonic thin-walled tube wave structure for sensing devices

Theoretical and experimental investigations of thin-walled tube acoustic wave devices for gravimetric sensing applications are presented. Integrated sensor configurations have been demonstrated by employing a sol-gel processed thin piezoelectric lead zirconate titanate (PZT) film. This was coated coaxially on stainless steel tubes and interdigital transducers (IDT) fabricated as the transmitter and receiver on the curved tube surfaces. We have observed tube waves along both the axial and circumferential directions between 1 and 6.6 MHz. We have also analyzed the mass sensitivities of different modes propagating along the tubes and shown that high mass sensitivity can be achieved by keeping the tube wall thin     

Residual phase noise measurements of VHF, UHF, and microwavecomponents

The results of residual phase noise measurements on a number of VHF, UHF, and microwave amplifiers, both silicon (Si) bipolar junction transistor (BJT) and gallium arsenide (GaAs) field effect transistor (FET) based, electronic phase shifters, frequency dividers and multipliers, etc., which are commonly used in a wide variety of frequency source and synthesizer applications are presented. The measurement technique has also been used to evaluate feedback oscillator components, such as the loop and buffer amplifiers, which can play important roles in determining an oscillator's output phase noise spectrum (often in very subtle ways). While some information has previously been published related to component residual phase noise properties, it generally focused on the flicker noise levels of the devices under test, for carrier offset frequencies less than 10 kHz. The work reported herein makes use of an extremely low noise, 500 MHz surface acoustic wave resonator oscillator (SAWRO) test source for residual phase noise measurements, both close-to-and far-from-the-carrier. Using this SAWRO-based test source at 500 MHz, we have been able to achieve a measurement system phase noise floor of -184 dBc/Hz, or better, for carrier offset frequencies greater than 10 kHz, and a system flicker phase noise floor of -150 dBc/Hz, or better, at 1 Hz carrier offset. The paper discusses the results of detailed residual phase noise measurements performed on a number of components using this overall system configuration. Several interesting observations related to the residual phase noise properties of moderate to high power RF amplifiers, i.e., amplifiers with 1 dB gain compression points in the range of +20 to +33 dBm, are highlighted     

Assessment of alcohol consumption and alcoholism in the elderly

This study evaluates characteristics associated with alcohol consumption or alcohol-related problems in an elderly population, as detected by CAGE questionnaire and self-reported alcohol intake respectively. Data were obtained from a multidimensional study carried out in a community-dwelling population aged 70-75 (n = 1205, 389 males and 816 females) living in the city center of Brescia, in northern Italy. All information was gathered by self-report. Male gender, better mood, daily function, somatic health, not living alone, and being married were significantly associated with self-reported alcohol consumption. Male gender, poorer cognitive function, and income dissatisfaction were significantly associated with alcohol problems as detected by CAGE. Data suggest that self-report of alcohol intake, though intrinsically loaded with imperfect internal consistency, does not necessarily indicate risk of alcoholism; on the contrary, it can reveal the positive psychological attitude of the drinking habit. CAGE questionnaire, which is sensitive to alcohol related problems, is associated with poor psychosocial conditions.     

Rhodopsin mutations in autosomal dominant retinitis pigmentosa

Retinitis pigmentosa is an inherited progressive disease which is a major cause of blindness in western communities. It can be inherited as an autosomal dominant, autosomal recessive, or X-linked recessive disorder. In the autosomal dominant form (adRP), which comprises about 25% of total cases, approximately 30% of families have mutations in the gene encoding the rod photoreceptor-specific protein rhodopsin. This is the transmembrane protein which, when photoexcited, initiates the visual transduction cascade. So far, 41 single-base-pair (bp) substitutions, one two-bp substitution, and four deletions ranging from 3 to 42 bp have been identified in this gene. These mutations do not appear to be significantly clustered in a specific part of the protein, but occur in all three major domains, namely the intradiscal, transmembrane, and cytoplasmic regions. Different mutations appear to cause differences in the severity of the disease, though there is considerable variability in severity even within the same family, at least in certain of these mutations. Identification of all the mutations involved in rhodopsin-RP should allow accurate and early detection of affected individuals, informed genetic counselling, as well as furthering our knowledge of the disease process involved.