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The objective of the study was to evaluate the efficacy of device-guided breathing to lower blood pressure (BP) in hypertensive type II diabetic patients. A randomized controlled trial was carried out in four urban family practice clinics in Israel. Non-insulin-dependent diabetic, hypertensive patients with uncontrolled BP, receiving antihypertensive therapy or those non-medicated were enrolled. Baseline characteristics of the 66 patients who completed the study (33 intervention and 33 control) were: 62% men, age 62+/-8 years (mean+/-s.d.); body mass index 29+/-5 kg/m2; systolic BP 148+/-11 mm Hg and diastolic BP 81+/-9 mm Hg. The intervention group used a device (RESPeRATE), which interactively guides the user towards slow and regular breathing by synchronizing respiration voluntarily to musical tones for 15 min daily for an 8-week period. The control group continued with their regular treatment. BP was measured in the clinic at baseline, after 4 weeks and at 8 weeks. Medication was unchanged for 4 weeks prior to and during the study period. The main outcome measure was the office BP change from baseline to the end of the 8-week period. BP was reduced in the treatment group (mean+/-s.e.) systolic -10.0+/-1.8 mm Hg and diastolic -3.6+/-1.3 mm Hg (P0.0001 and P0.01), but not in the controls +1.6+/-2.1 and -1.0+/-1.4 mm Hg P0.4 and P0.4, respectively. Test for between group difference P0.0001 and P=0.08. The subjects were highly compliant with the treatment, performing 75% of the requested exercise sessions. Greater BP reduction was observed with increased compliance with device usage (P=0.01 and P=0.001). It is concluded that self-treatment with device-guided breathing at home for 8 weeks by non-insulin-dependent diabetic patients was associated with a substantial reduction in office systolic BP.

We hypothesise that routinely applied short sessions of slow and regular breathing can lower blood pressure (BP). Using a new technology BIM (Breathe with Interactive Music), hypertensive patients were guided towards slow and regular breathing. The present study evaluates the efficacy of the BIM in lowering BP. We studied 33 patients (23M/10F), aged 25-75 years, with uncontrolled BP. Patients were randomised into either active treatment with the BIM (n = 18) or a control treatment with a Walkman (n = 15). Treatment at home included either musically-guided breathing exercises with the BIM or listening to quiet music played by a Walkman for 10 min daily for 8 weeks. BP and heart rate were measured both at the clinic and at home with an Omron IC BP monitor. Clinic BP levels were measured at baseline, and after 4 and 8 weeks of treatment. Home BP measurements were taken daily, morning and evening, throughout the study. The two groups were matched by initial BP, age, gender, body mass index and medication status. The BP change at the clinic was -7.5/-4.0 mm Hg in the active treatment group, vs -2.9/-1.5 mm Hg in the control group (P = 0.001 for systolic BP). Analysis of home-measured data showed an average BP change of -5.0/-2.7 mm Hg in the active treatment group and -1.2/+0.9 mm Hg in the control group. Ten out of 18 (56%) were defined as responders in the active treatment group but only two out of 14 (14%) in the control group (P = 0.02). Thus, breathing exercise guided by the BIM device for 10 min daily is an effective non-pharmacological modality to reduce BP.

Research has shown that both the support of anonymity and the use of appropriate incentives can lead to improved group performance. Anonymity enables a more open discussion resulting in a more critical analysis of a problem. Rewards can motivate individuals to cooperate, giving them the incentive to share valuable information with the group. Unfortunately, these two mechanisms are both dependent on the ability to identify the contributor. Anonymity hides the identity of the contributor, while the support of individualized, performance-based rewards requires the rewarding agent to be able to determine the identity of the contributor. This contradictory requirement has prevented the simultaneous used of anonymity and performance-based rewards in decision making. Using group decision support systems as a basis, this work identifies procedures to simultaneously support participant anonymity and performance-based rewards. Mechanisms based on public key encryption technologies are presented which make it possible to distribute individual rewards to anonymous contributors, guarantee that only the contributor can claim a reward for her contribution, verify that a reward has been distributed, and be able to deliver this reward in such a way that the identity of the anonymous contributor is protected. This is accomplished without the rewarding agent ever knowing the identity of the recipient.

This paper presents a new policy called the threshold priority policy (TPP) for assigning channels in cellular networks. The performance of TPP is compared with the performance of the well-known cutoff priority policy (CPP) and the nonprioritized complete sharing policy (CSP). Several numerical experiments are done for various values of offered load and portable mobility. The results are compared using three unified performance metrics which take into account the trade-off between new call blocking probability and the forced termination probability.

Laser photodissociation of respiratory proteins is followed by fast geminate recombination competing with escape of the oxygen molecule into the solvent. The escape rate from myoglobin or hemerythrin has been shown previously to exhibit a reciprocal power-law dependence on viscosity. We have reinvestigated oxygen escape from hemerythrin using a number of viscous cosolvents of varying molecular weight, from glycerol to dextrans up to 500 kDa. In isoviscous solutions, the strong viscosity dependence observed with small cosolvents is progressively reduced upon increasing the cosolvent's molecular weight and disappears at molecular weights greater than about 100 kDa. Thus, viscosity is not a suitable independent parameter to describe the data. The power of the viscosity dependence of the rate coefficient is shown here to be a function of the cosolvent's molecular weight, suggesting that local protein-solvent interactions rather than bulky viscosity are affecting protein dynamics.

A new approach to the joint selection of primary and secondary routes in a network with unreliable components is presented. The mathematical model captures the changes in the operational characteristics of the network as it adapts to failures. Lagrangian relaxation and subgradient optimization techniques are used to obtain good heuristic solutions to the problem, as well as lower bounds to be used as benchmarks against which the quality of the solution is assessed. Results of numerical experiments are reported, and directions for further enhancements of the model are discussed. >

International audience; In this paper, we propose a new sensor deployment strategy by considering both a probabilistic sensor detection model and a monitored area with geographical irregularity requirement of the sensed events. In this case, each point in the deployment field needs a specific minimum guarantee in event detection probability. The main objective is to find the minimum number of senors and their positions, in order to guarantee the requirement event detection threshold. Thus, we propose a new scalable deployment strategy based on virtual forces. The fundamental idea of our proposal is to adjust the number and the position of sensors according to virtual forces that must be computed for each sensor. The performance evaluation shows that our proposal obtained the best results compared to several other sensor deployment strategies founded in the literature.

The author develops a nonlinear formulation of the topological design problem, and obtains a Lagrangean relaxation of the problem. The Lagrangean solutions provide lower bounds on the optimal solutions, which are further improved using subgradient optimization procedures. Heuristics are developed for generating feasible solutions to the problem. The quality of solutions generated by this heuristic are compared to the lower bounds generated by the Lagrangean procedures on a set of test cases. >

To examine the efficacy of a new device, which slows and regularises breathing, as a non-pharmacological treatment of hypertension and thus to evaluate the contribution of breathing modulation in the blood pressure (BP) reduction.Randomised, double-blind controlled study, carried out in three urban family practice clinics in Israel.Sixty-five male and female hypertensives, either receiving antihypertensive drug therapy or unmedicated. Four patients dropped out at the beginning of the study.Self treatment at home, 10 minutes daily for 8 consecutive weeks, using either the device (n = 32), which guides the user towards slow and regular breathing using musical sound patterns, or a Walkman, with which patients listened to quiet music (n = 29). Medication was unchanged 2 months prior to and during the study period.Systolic BP, diastolic BP and mean arterial pressure (MAP) changes from baseline.BP reduction in the device group was significantly greater than a predetermined 'clinically meaningful threshold' of 10.0, 5.0 and 6.7 mm Hg for the systolic BP, diastolic BP and MAP respectively (P = 0.035, P = 0.0002 and P = 0.001). Treatment with the device reduced systolic BP, diastolic BP and MAP by 15.2, 10.0 and 11.7 mm Hg respectively, as compared to 11.3, 5.6 and 7.5 mm Hg (P = 0.14, P = 0.008, P = 0.03) with the Walkman. Six months after treatment had stopped, diastolic BP reduction in the device group remained greater than the 'threshold' (P0.02) and also greater than in the walkman group (P = 0.001).The device was found to be efficacious in reducing high BP during 2 months of self-treatment by patients at home. Breathing pattern modification appears to be an important component in this reduction.

The displacement‐displacement space time correlation functions are calculated for a cubic harmonic lattice embedded in a viscous fluid. For the one‐dimensional case we find a |t| type of behavior of the correlation functions at long times. This may lead to observable effects in the dynamic structure factors. A strong dependence of the static and dynamic structure factors both on the angle of scattering and on the orientation of the lattice, is found.

The problem of selecting a single route for each class of service and each pair of communicating nodes in an SNA network is considered. The nodes, links, sets of candidate routes, and traffic characteristics are given. The goal is to select a set of routes which minimizes the expected network end-to-end queueing and transmission delay. Queueing is modeled as a network of M/M/1 queues which leads to a nonlinear combinatorial optimization problem. Using Lagrangean relaxation and subgradient optimization techniques, we obtain a tight lower bound on the minimal expected delay as well as sets of feasible solutions for the problem. An experimental interactive system has been used to evaluate the procedure; very favorable results have been obtained on a variety of networks.

This paper presents a method for serial combination of truck trips to minimize the total cost of deadheading, subject to constraints on the allowed combinations. The problem is initially formulated as an integer transportation problem with extra compatibility constraints, and then reduced to a classical transportation problem. Modifications of the classical algorithm led to a fifty-fold reduction in computer time, and permit solution of a 1000 × 1000 problem in less than two minutes of computer time. Implementation of the method led to considerable cost savings over the older manual procedure.

The last few years have witnessed the intensive growth of computer communication networks. The need for nationwide and multination computer communication systems brought about the development of packet-switching networks such as the ARPANET. In this paper we examine a model for computer-to-computer communication via a satellite link. In each network, a single node, the satellite communication concentrator (SCC), manages the flow of information between the terminals in the network and the satellite link. The SCC buffers messages from the terminals and retransmits them over the satellite channel. Buffer space claimed by a message is made free only after the SCC receives an acknowledgment from the receiving network; transmission errors cause the buffer to retransmit the message. The statistical behavior of such a system is considered.

The effects of pH changes on the miniature endplate current (mepc) and on endplate current fluctuations (acetylcholine [ACh] noise) were examined at the neuromuscular junction in vitro in two species of frogs. In Rana pipiens the relationship between the decay time constant of the mepc (tau') and pH had a symmetrical bell shape; the value of tau' being largest at pH 7 and decreasing at more acid or more alkaline pH. In acid pH the mepc amplitude (A) decreased relative to its value at pH 7, and in alkaline pH A increased. In Rana ridibunda a narrower and asymmetric bell-shaped dependence of tau' on pH, having a maximum of pH 5.5, was found. The mepc amplitude was again reduced in acid pH but had a peak at pH 5.5. Also, its value at pH 9 was larger than at pH 7. These results were obtained with a number of different buffers and were not found to be sensitive to the nature of the buffer chosen. By performing ACh-noise analysis we found that in Rana pipiens at acid pH (5.5-5.0), the single channel conductance (gamma) and the single channel open time (tau) were significantly reduced relative to their value at pH 7. However, in Rana ridibunda at acid pH (5.4) gamma was unchanged and tau was markedly increased relative to their values at pH 7. The results can be explained quantitatively by electrostatic interaction between two fixed and titratable ionic groups and a mobile charge in the receptor molecule. The model fits the data for groups having pKs approximately 4.8 and approximately 9.8 for Rana pipiens and approximately 4.6 and approximately 6.3 for Rana ridibunda. The groups can be tentatively identified as amino acid residues; glutamic or aspartic and lysine or tyrosine for Rana pipiens; glutamic or aspartic and histidine for Rana ridibunda. The difference in the fitted values of the other model parameters for these two species can be attributed to differences in the spatial configuration of the charged groups.

The combined problem of selecting a primary route for each communicating pair and a capacity value for each link in computer communication networks is considered. The network topology and traffic characteristics are given: a set of candidate routes and of candidate capacities for each link are also available. The goal is to obtain the least costly feasible design where the costs include both capacity and queuing components. Lagrangean relaxation and subgradient optimization techniques were used to obtain verifiable solutions to the problem. The method was tested on several topologies, and in all cases good feasible solutions, as well as tight lower bounds, were obtained. The model can be generalized to deal with different classes of customers, characterized by different priorities, message lengths, and/or delay requirements. >

Given the set of intended transactions, the authors model the problem of choosing the most efficient decomposition of the universal set of attributes. Unlike other models which neglect the logical structure developed in database theory, the model developed incorporates it as part of a mathematical program. This provides a comprehensive and an integrated formulation for the combined logical and physical database design problem. The integrated problem and its epsilon -approximation schemes are shown to be NP-complete. An example shows the benefit of such an approach over more conventional ones. >

The displacement–displacement space–time correlation functions and the static and incoherent dynamic structure factors are calculated for a layered harmonic lattice. The continuous transition from 3D to 2D behavior of the various quantities as functions of the interlayer coupling is analyzed. Criteria for probing the 2D behavior are obtained along with suggestions and predictions for relevent scattering experiments.

This paper presents a model for designing the architecture of a distributed computing system of the type used to support the management and control activities of a large corporation. The input to the design process consists of two major data components describing the inputs and outputs to the information system and the relationships between them. Based on this information and the structure of communication and processing costs, an optimization model is formulated. It aggregates transactions in distributed databases, selects the locations in which those databases will be placed, assigns data sources to those databases, and selects for each report the report generation location. The problem is formulated as a combinatorial optimization problem and procedures are developed for computing lower bounds on the value of the optimal solution and heuristics for generating good feasible solutions for the problem. The procedures were tested on several examples and have generated good initial designs. Computational examples are presented to design problems including organizations with a hierarchical structure.

A general mathematical model for a network design problem with reliability constraints and a revised formulation which seems particularly appropriate for fiber-optics networks is presented. Upper and lower bounding procedures based on continuous relaxations of this modified formulation are described. Preliminary computational results are reported. Limited computational results indicate a good performance of the algorithm, producing a gap between lower and upper bounds that is sufficiently small for a branch-and-bound procedure to be applicable. >

The effect of viscosity on the rate of catalysis of carboxypeptidase A has been tested. By use of the tripeptide carbobenzoxy-l-alanyl-l-alanyl-l-alanine [Z(L-Ala)3] as substrate, it was shown that most of the effect on the hydrolysis rate caused by the presence of 30 or 40% methanol or glycerol in aqueous solution can be ascribed to a contribution of viscosity to the catalytic rate constant, kcat. Arrhenius plots of kcat in 30 and 40% glycerol or methanol are linear and almost parallel. When the rate constants are "corrected" for the viscosity of various media, the difference between the various Arrhenius plots is considerably reduced; it vanishes, within experimental error, when the effect of the dielectric constant of the solutions is taken into account as well. It is proposed that the viscosity of the medium can influence the rate-limiting step of the enzymic reaction, which is the rate of transitions over the energy barrier preceding product formation. According to the suggested mechanism, the enzyme--substrate complex can overcome this energy barrier by viscosity-dependent structural fluctuations. The quantitative agreement between the theory and the experimental results suggests that (a) due to the temperature dependence of the viscosity of the solution, the potential energy barrier of the reaction is about 5 kcal/mol lower than the observed activation energy and (b) information about the structural flexibility of the complex can be obtained by kinetic measurements.

The adiabatic compressibility of several globular proteins has been measured by using an ultrasonic technique in the frequency range 0.5 to 10 MHz. The contributions to the measured compressibility from the protein matrix and from surface processes involving ionization of side chains and solvation effects are discussed. The internal protein compressibility is very low, indicating the existence of "dynamic domains" which are tentatively assigned to secondary structure elements.

The information processing industry has shifted from the conventional mathematical computation to information management. Interactive use of a system with large data bases is now widespread, and the data base has become one of the key factors central to an overall system design. This, in turn, has prompted the development of new peripheral devices.

Capacitated spanning tree problems appear frequently as fundamental problems in many communication network design problems. An integer programming formulation and a new set of valid inequalities are presented for the linear characterization of the problem. A combination of a subgradient optimization procedure and an augmented Lagrangean-based procedure is used to generate tight lower bounds. The procedure begins with an explicit representation of a subset of the constraints, and the corresponding Lagrangean problem is solved. The solution is examined in order to identify implicit constraints that are violated. Those are added to the Lagrangean problem, forming an expanded problem, and an efficient dual ascent procedure is then applied. When no further improvement is possible through this procedure, a subgradient optimization procedure is invoked in order to further tighten the lower bound value. An exchange heuristic is applied to the nonfeasible Lagrangean solution, in an attempt to generate good feasible solutions to the problem. The procedure has been tested and has generated bounds that are significantly better than ones obtained through previously published procedures.

An interactive system for computer-assisted medical diagnosis is described. Medical experts are provided with a framework in which to translate the knowledge on which their decisions are based. The technique is based on simulating the physician's own diagnostic process. The approach taken allows consistency and completeness checks to be made, thereby achieving a high degree of reliability. Information related to a given specialty is described in terms of disorder patterns, clinical facts, and logical relationships among the clinical data. Laboratory results are processed by a subsystem which uses physician-supplied rules to establish validity and to interpret the test data with respect to their diagnostic significance. The system incorporates a dynamically generated questionnaire which provides efficient gathering of anamnestic, observational, and other clinical parameters. The physician is prompted for relevant patient data by an algorithm which assures that an almost minimal amount of information is requested. Simulation facilities allow the user to examine clustering phenomena among disorders, and an option is included that traces the logic of any decision taken to exclude candidates for a final diagnosis.

Time course measurements of the action of muscarinic antagonists were performed in the spontaneously beating carp atrium. Several high affinity drugs, which embody the quinuclidine structure were examined. The structural flexibility of these molecules was reflected in the dissociation of the drugs from the muscarinic receptor. The dissociation of rigid drugs was very much prolonged as compared to flexible drugs of the same affinity.

Analysis of the plethysmographic pulse volume contour in terms of "crest time", made in 1940-1960, revealed age dependence and clinically significant variations between health and disease, including arteriosclerosis, hypertension and various dermatoses. A new parameter--"minimum rise-time" (MRT) is suggested and defined from pulse volume contour. In health it was found to be age dependent using finger photoplethysmography. The MRT of the pulse volume is shown by a model 1) to be associated with the mechanical properties (viscoelasticity) of the vascular wall, 2) to approximate the MRT of the pulse pressure, and 3) to be free of ambiguities found in "crest time" and "half rise-time" previously used. The analysis suggests that the gradient of the MRT along peripheral vessels might be a clinical indication of variations in the mechanical properties of the vascular wall.

A differential method for the measurement of sound velocity in solutions is described. The instrument uses two identical acoustic resonators and a newly developed electronic measuring system. The sound velocity is determined with a relative accuracy of ≊3×10−6 over the entire frequency range 0.5–10 MHz. The instrument has been used to determine the compressibility of protein solutions and to study their velocity dispersion.

WE demonstrate here the feasibility of the observations of hydrodynamic instabilities in a lead acid battery during the discharge process. We use a system comprising two horizontal electrodes immersed in a transparent cell. The electrodes contain in the charged state porous PbO2, the ‘positive’ electrode, and porous Pb, the ‘negative’ electrode. The electrodes were prepared to commercial standards using common industrial processes.

The displacement–displacement space–time correlation functions and static and dynamic structure factors are calculated for a chainlike harmonic lattice. The continuous transition from 3D to 1D behavior of the various quantities as functions of the interchain coupling is analyzed. Criteria for probing the 1D behavior are obtained along with suggestions and predictions for relevent scattering experiments. Existing experimental results are found to be compatible with the theory.