Effects of gemfibrozil and ciprofibrate on plasma levels of tissue-type plasminogen activator, plasminogen activator inhibitor-1 and fibrinogen in hyperlipidaemic patients

Evaluation of fibrate treatment in humans has focused primarily on its anti-lipidaemic effects. A potentially favourable haemostasis-modulating activity of fibrates has also been recognized but the data are not consistent. We sought to learn more about this variability by examining the effects of gemfibrozil and ciprofibrate on plasma levels of tissue-type plasminogen activator (t-PA), plasminogen activator inhibitor-1 (PAI-1) and fibrinogen in primary hyperlipidaemic patients after six and twelve weeks of treatment using different assay systems for PAI-1 and fibrinogen. Although both fibrates effectively lowered triglyceride and cholesterol levels, no effect on the elevated baseline antigen levels of t-PA and PAI-1 was observed after fibrate treatment. However, both fibrates influenced plasma fibrinogen levels, albeit in a different way. Fibrinogen antigen levels were elevated by 17.6% (p <0.05) and 24.3% (p <0.001) with gemfibrozil after six and twelve weeks, respectively, whereas with ciprofibrate there was no effect. Using a Clauss functional assay with either a mechanical end point or a turbidity-based end point, no significant change in fibrinogen levels was seen after six weeks of gemfibrozil treatment. However, after twelve weeks, gemfibrozil enhanced functional fibrinogen levels by 7.2% (p <0.05) as assessed by the Clauss mechanical assay, but decreased functional fibrinogen levels by 12.5% (p <0.0001) when a Clauss assay based on turbidity was used. After six or twelve weeks of ciprofibrate treatment, functional fibrinogen levels were decreased by 10.1% (p <0.001) and 10.5% (p <0.0001), respectively on the basis of Clauss mechanical and by 14.2% (p <0.001) and 28.2% (p <0.0001), respectively with the Clauss turbidimetric assay. A remarkable and consistent finding with both fibrates was the decrease in functionality of fibrinogen as assessed by the ratio of functional fibrinogen (determined by either of the two Clauss assays) to fibrinogen antigen. Taken together, our results indicate that at least part of the variability in the effects of fibrates on haemostatic parameters can be explained by intrinsic differences between various fibrates, by differences in treatment period and/or by the different outcomes of various assay systems. Interestingly, the two fibrates tested both reduced the functionality of fibrinogen.     

Minimax control of a process in a linear uncertain-stochastic system with incomplete data

Consideration is given to the control problem in a linear stochastic differential system where constant noise intensities in equations of state and observation are prescribed only accurate within the membership of some known sets. For control optimization, an integral root-mean-square performance criterion is used. The problem is solved by the transition to a dual one, which makes it possible to prove the existence of a saddle point of the criterion and obtain an explicit expression for the minimax control operator as functions of the solution to the dual problem. To solve the latter, an iteration algorithm is proposed; the convergence of the algorithm is proved and investigated by a model example.     

Effects of note-taking on perceived counselor social influence during a career counseling session.

Examined the effects of counselor note-taking behavior on participants' impressions of a counselor during a career counseling session. A total of 140 participants (70 men and 70 women) rated 1 of 2 videotapes designed to credibly simulate a real career counseling interview. Note-taking was the independent variable. Results of this study suggest that whether a counselor is observed in a note-taking or non-note-taking condition has no significant effect on perceived counselor expertness, attractiveness, or trustworthiness. However, there was a significantly greater willingness of the participants to see the counselor who refrained from note-taking. Results offer tentative suggestions for those counselors who choose to take notes during a career counseling session. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Five channel WDM soliton pulse generation using sinusoidally drivenelectroabsorption modulators in 16×1 laser/modulator array

Five wavelength multiplexed pulse streams are generated in an integrated 16×1 laser modulator array by sinusoidally driving five of the potential 16 electroabsorption modulators. At a repetition rate of 2.5 GHz, near transform-limited pulses spaced in wavelength over 7.6 nm are observed. Pseudorandom coding of one channel is achieved by applying an electrical RZ data signal to the modulator     

Endocrine disorders in critically ill children

Endocrine disorders in critically ill infants and children can be the manifestation of an existing but previously unrecognized condition, or hormonal derangements precipitated by deleterious effects on endocrine function of a critical illness or its prescribed therapy. To achieve successful resolution of these crises, a general understanding of various endocrine dysfunctions, clinical symptomatology, diagnosis, and medical and nursing management is essential.     

Training analysis of adaptive interference suppression fordirect-sequence code-division multiple-access systems

This paper studies the transient behavior of an adaptive near-far resistant receiver for direct-sequence (DS) code-division multiple-access (CDMA) known as the minimum mean-squared error (MMSE) receiver. This receiver structure is known to be near-far resistant and yet does not require the large amounts of side information that are typically required for other near-far resistant receivers. In fact, this receiver only requires code timing on the one desired signal. The MMSE receiver uses an adaptive filter which is operated in a manner similar to adaptive equalizers. Initially there is a training period where the filter locks onto the signal that is sending a known training sequence. After training, the system can then switch to a decision-directed mode and send actual data. This work examines the length of the training period needed as a function of the number of interfering users and the severity of the near-far problem. A standard least mean-square (LMS) algorithm is used to adapt the filter and so the trade-off between convergence and excess mean-squared error is studied. It is found that in almost all cases a step size near 1.0/(total input power) gives the best speed of convergence with a reasonable excess mean-squared error. Also, it is shown that the MMSE receiver can tolerate a 30-40 dB near-far problem without excessively long convergence time     

On the Achievable Delay Margin Using LTI Control for Unstable Plants

Handling delays in control systems is difficult and is of long-standing interest. It is well known that, given a finite-dimensional linear time-invariant (FDLTI) plant and controller forming a strictly proper stable feedback connection, closed-loop stability will be maintained under a small delay in the feedback loop, although most closed loop systems become unstable for large delays. One previously unsolved fundamental problem in this context is whether, for a given FDLTI plant, an arbitrarily large delay margin can be achieved using LTI control. Here, we adopt a frequency domain approach and demonstrate that, for a strictly proper real rational plant, there is a uniform upper bound on the delay that can be tolerated when using an LTI controller, if and only if the plant has at least one closed right half plane pole not at the origin. We also give several explicit upper bounds on the achievable delay margin, and, in some special cases, demonstrate that these bounds are tight.