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The achieved results in the field of coherent optical frequency reflectometry (COFR) based on a source of frequency-tunable radiation of a new type—a fiber self-scanning laser—are reviewed. It was shown that the developed COFR can be used for the tasks of characterization of optical elements, sensors, vibration measurement, and gas analysis at lengths of several tens of meters with submillimeter spatial resolution. Prospects for the development of this trend are also discussed. [ABSTRACT FROM AUTHOR]

A module has been designed for automated acquisition and preliminary processing of optical signals from devices based on a fiber laser with frequency self-sweeping. The primary processing, i.e., pulse-by-pulse data normalization, is performed using a microcontroller. Signals are then transmitted to a personal computer for further processing in the form of the dependence of the signal amplitude on the pulse number. The optimal characteristics of the used analog-to-digital converter are as follows: the sampling rate is 5 MHz and the bit depth is at least 8 bits. The operation of the module was tested in an optical frequency reflectometer for interrogating fiber sensors. [ABSTRACT FROM AUTHOR]

Background- Most guidelines for treatment of hypertension recommend a blood pressure (BP) goal of <140/90 mm Hg, and a more aggressive goal of <130/80 mm Hg for patients with diabetes mellitus. However, in the recent Action to Control Cardiovascular Risk in Diabetes (ACCORD) trial, a lower BP was not beneficial. The optimal BP target in subjects with diabetes mellitus or those with impaired fasting glucose/glucose tolerance is therefore not well defined. Methods and Results- We performed PUBMED, EMBASE, and CENTRAL searches for randomized clinical trials from 1965 through October 2010 of antihypertensive therapy in patients with type 2 diabetes mellitus or impaired fasting glucose/impaired glucose tolerance that enrolled at least 100 patients with achieved systolic BP of <=135 mm Hg in the intensive BP control group and <=140 mm Hg in the standard BP control group, had a follow-up of at least 1 year, and evaluated macrovascular or microvascular events. We identified 13 randomized clinical trials enrolling 37 736 participants. Intensive BP control was associated with a 10% reduction in all-cause mortality (odds ratio, 0.90; 95% confidence interval, 0.83 to 0.98), a 17% reduction in stroke, and a 20% increase in serious adverse effects, but with similar outcomes for other macrovascular and microvascular (cardiac, renal, and retinal) events compared with standard BP control. The results were similar in a sensitivity analysis using a bayesian random-effects model. More intensive BP control (<=130 mm Hg) was associated with a greater reduction in stroke, but did not reduce other events. Meta-regression analysis showed continued risk reduction for stroke to a systolic BP of <120 mm Hg. However, at levels <130 mm Hg, there was a 40% increase in serious adverse events with no benefit for other outcomes. Conclusions- The present body of evidence suggests that in patients with type 2 diabetes mellitus/impaired fasting glucose/impaired glucose tolerance, a systolic BP treatment goal of 130 to 135 mm Hg is acceptable. However, with more aggressive goals (<130 mm Hg), we observed target organ heterogeneity in that the risk of stroke continued to fall, but there was no benefit regarding the risk of other macrovascular or microvascular (cardiac, renal and retinal) events, and the risk of serious adverse events even increased. [ABSTRACT FROM AUTHOR]

The first results are presented that demonstrate the applicability of a coherent optical frequency-domain reflectometer based on a self-sweeping fiber laser for sensing. An array of various fiber Bragg gratings (FBGs) was used as the sensing line. It is shown that FBGs with a reflection spectrum that lies outside the scan region of ​​our source can be used in the developed reflectometer. Using the frequency-domain reflectometry technique, it is possible to perform spatial separation of FBG sensors, even with the use of the same reflection wavelengths. The possibility of measuring the temperature has been experimentally demonstrated. [ABSTRACT FROM AUTHOR]