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PubMed2006

Inequity in mental health care under Canadian universal health coverage.

OBJECTIVE: Previous research has produced conflicting evidence about socioeconomic disparities in mental health care under universal health coverage in Canada. This study sought to determine equity in the delivery of ambulatory services from psychiatrists and family physicians for mental health problems in this setting. METHODS: Outpatient billing claims and neighborhood socioeconomic status were examined with cross-sectional analysis. The study area consisted of the central southern portion of the city of Toronto, Ontario, including the city's downtown core. This urban setting is an economically and culturally diverse area. A total of 1,221 homogeneous enumeration areas (local neighborhoods) were surveyed, and data were examined for the 746,141 residents of these areas who had had a health visit in 2000. Rates of mental health visits to family physicians and psychiatrists were compared across socioeconomic quintiles. Socioeconomic status was determined according to educational attainment in the enumeration area. RESULTS: Claimants from neighborhoods with the highest socioeconomic status were 1.6 times as likely as those from neighborhoods with the lowest socioeconomic status to use psychiatric care. Among persons who received care from a psychiatrist, claimants from neighborhoods with the highest socioeconomic status had significantly more psychiatric claims than those from neighborhoods with the lowest socioeconomic status. No significant gradients were found for either sex for any use of mental health care provided by family physicians. Among females, service users from the highest socioeconomic areas had more mental health visits to family physicians than those from the lowest socioeconomic areas. CONCLUSIONS: Marked socioeconomic disparities were found in the use of care from a psychiatrist. Unlimited coverage of physician-provided mental health care is insufficient to fairly distribute services to those most in need.

Adult↗
PubMed1984

Evaluation of a colorimetric test for the determination of alpha-amylase with p-nitrophenylheptaoside as substrate.

A continuous method for the determination of alpha-amylase activity with a defined substrate has been published by Rauscher et al. in Berichte der Osterreichischen Gesellschaft für Klinische Chemie 4, 150 (1981). It offers the following advantages: good practicability, easy adaptation to analysers and short incubation time. Twenty-one laboratories took part in a multicentric study on this method, working with different instruments and manual procedures at three temperatures. Additionally, all laboratories participated in a laboratory improvement program, in order to discriminate systematic from accidental errors. Data on imprecision, linearity, interferences and comparability of the method have been presented at a workshop. The resulting coefficients of variation for imprecision in series as well as from day to day were 0.6-6.3% and 1.3-7.7%, respectively. No interferences from bilirubin, glucose, maltose and 37 selected drugs were found. The results from the described method correlate well with those from an UV-test (substrate: maltoheptaose); compared with other methods, however, the expected systematic deviations were observed. Reference values for 25, 30 and 37 degrees C are indicated in this report.

Colorimetry↗
PubMed2005

Superheated water chromatography of low molecular weight polyethylene glycols with ultraviolet detection.

Superheated water chromatography (SWC) with ultraviolet detection was applied to the separation of low molecular weight polyethylene glycols (PEGs). PEG oligomers could be detected sensitively when the detection wavelength was set at 190 nm. The effect of column temperature on the separation of PEG oligomers was investigated. The elution time of all PEG oligomers decreased with increase in the column temperature; linear relationships were obtained between ln k and 1/T. A temperature-programmed SWC separation enabled the baseline separation of a PEG 200 sample within 50 min.

Journal Article↗
PubMed1991

Mapping DNA by stochastic relaxation: schedule for optimal annealing.

The analysis of the various cooling schedules for the simulated annealing algorithm is made towards the restriction map construction. Algorithm behaviour under control of three different cost functions is considered and the discrete cost function is found to handle successfully experimental data with realistic error sizes. A program using this function has been derived from the algorithm to construct linear and circular DNA maps.

Algorithms↗
PubMed1996

Phenotypic relationship of yield and type scores from first lactation with herd life and profitability.

Milk records from Ayrshire, Brown Swiss, Guernsey, Jersey, and Milking Shorthorn cows that first calved between 18 and 35 mo were combined with scores for linear type traits collected before 43 mo during first lactation to study herd life and lifetime profitability. Profitability (discounted relative net income) was the value of milk, calves, and cow salvage minus fixed costs, operating costs, and cow depreciation costs. Cows were included if they appeared only in a single herd and if the herd remained on test for 72 mo after birth date of the cow. Phenotypic correlations were computed for milk and fat yields and for 14 type traits during first lactation with nine variables for lifetime performance from 3895 Ayrshire, 7997 Brown Swiss, 20,179 Guernsey, 71,731 Jersey, and 628 Milking Shorthorn cows. Multiple correlations for predicting discounted relative net income for the four breeds with the most data were 0.43 to 0.46 from milk and fat yields (linear and quadratic effects) during first lactation, 0.11 to 0.29 from final score, and 0.21 to 0.33 from all type traits. Type scores had considerably less predictive ability than yield during first lactation for predicting profitability and had limited predictability after yield was included. Final score increased multiple correlations only 0.00 to 0.02 above that for yield for the same four breeds. Final score plus 13 type traits (linear, quadratic, and interaction effects) increased multiple correlations only 0.02 to 0.04 above that for yield. Because of the limited value of some of the linear type traits, an effort should be initiated to eliminate them from programs of breed associations.

Aging↗
PubMedDate not supplied

Population pharmacokinetics of cisplatin in patients with advanced ovarian cancer during intraperitoneal hyperthermia chemotherapy.

The objective of this study was to determine the pharmacokinetic profile of total platinum administered by hyperthermic peritoneal perfusion (HPP) in 16 patients with ovarian cancer. The patients had a performance status of lIIalpha/b/c on the FIGO scale. They received 60, 80 or 100 mg of cisplatin. The percent of cisplatin remaining in the body after the peritoneum was emptied averaged 65% (41.7-85.4%). The average ratio between peritoneal drug concentrations and plasma concentrations was 73. A Bayesian estimation of individual phamacokinetic parameters was carried out using the non-linear mixed-effect modeling approach as implemented in the NONMEM computer program. A two-compartment model with an additional peritoneal cavity compartment was used to fit the data. Large interindividual variability of the pharmacokinetic parameters occurred The maximum platinum concentration in plasma was reached between 1 and 1.5 hours after the beginning of administration; it ranged from 0.37 to 1.7 microg/ml (1.9 to 8.72 microM). The elimination half-life was 80 hours (48-152 hours and the area under the plasma concentration time curve normalized to a 100 mg cisplatin dose was 79 mg/liter x hours. The simultaneous fit of perfusate and plasma concentrations allowed us to estimate the percent of cisplatin that reached the systemic circulation at about 20%. At time infinity, the urinary cisplatin recovery accounted for only 20% of the administered dose. The results in this study showed that a high proportion of the cisplatin dose was absorbed by target tumor cells. In spite of the advanced disease of patients at the time of HPP, 37.5% of them were still alive three years after HPP (ie., 3-6 years after cancer diagnosis) and 12.5%, 7 years after HPP (i.e., 8 years after cancer diagnosis).

Adult↗
PubMed2004

[Study on thermo-sensitive intelligent targeting type drug carriers (II) microcapsules with grafted thermo-sensitive gates].

Environmental stimuli-responsive microcapsules are getting more and more interests because of their potential applications in site-specific and time- and rate-programmed controlled-release. In this study, thermo-responsive microcapsules with linear grafted poly(N-isopropylacrylamide) (PNIPAM) gates on the inner pore surface were prepared, and the thermo-responsive controlled-release experiments were carried out. Interfacial polymerization was introduced to prepare polyamide porous microcapsules, and plasma-graft pore-filling polymerization was used to graft PNIPAM into the pore of the microcapsule membranes. The experimental results showed that PNIPAM-grafted microcapsules were featured with thermo-responsiveness due to the thermoresponsive swollen-shrunken property of PNIPAM chains grafted on the inner pore surface of the microcapsule membrane. At temperatures below the lower critical solution temperature (LCST), the linear grafted PNIPAM chains on the inner pore surface were in the swollen state, and the pores in the membrane were closed and the solute molecules were restrained to pass, as a result the release rate was low. In contrast, the grafted PNIPAM chains were in the shrunken state at temperatures above the LCST, and therefore the pores in the membrane were open, and a high release rate was the result.

Acrylic Resins↗
PubMedDate not supplied

A programmable variable waveshape generator for electrosurgical research.

A variable waveform electrosurgical unit (VWESU) was designed and used for electrosurgical research. The design criteria included the ability to modulate the amplitude of a sinusoidal carrier on a cycle-by-cycle basis, output power equivalent to commercial generators, and provision for varying the output impedance. These were realized with a microprocessor-controlled variable waveform generator which allows the user to program waveforms into memory with a set of simple descriptive commands, a linear power amplifier, and a custom output transformer. The contents of the memory are directly pipelined to a set of analog switches, which modulate the radio-frequency carrier with one of eight amplitude levels, thereby bypassing the speed limitations of the microprocessor.

Biomedical Engineering↗
PubMed1979

Calibration and monitoring of spectrometers and spectrophotometers.

We have delineated some of the factors affecting the performance of spectrometers and spectrophotometers in the clinical laboratory and have presented some of the methods for verifying that these instruments are functioning properly. At a minimum, every laboratory should perform periodic inspections of spectrometric functions to check wavelength calibration, linearity of detector response, and stray radiation. Only through such an inspection program can a laboratory ensure that these instruments are not contributing to inaccurate analytical results.

Color↗
PubMed1983

High pressure liquid chromatographic determination of putrefactive amines in foods.

A high pressure liquid chromatographic (HPLC) procedure is described for determining the following putrefactive amines: histamine, tyramine, putrescine, cadaverine, tryptamine, and beta-phenylethylamine. The amines were extracted from tuna or cheese with methanol. Further cleanup was performed by sequential extractions with butanol and HCl. The acid extract was dried, and residues were derivatized with dansyl chloride. HPLC separations were performed on an Ultrasphere-ODS column at 33 degrees C. A gradient elution program was used; the total elution time was less than 17 min. Linear standard curves with high correlation coefficients were obtained. The procedure allowed good recoveries of histamine, tyramine, putrescine, and cadaverine; recoveries of tryptamine and beta-phenylethylamine were lower but constant. With this method, some swiss cheese samples were found to contain considerable amounts of histamine, tyramine, putrescine, cadaverine, and beta-phenylethylamine. Canned tuna samples had very low levels of these amines. Since the presence of amines at high levels has been associated with tuna decomposition, this method may be useful in identifying decomposed fish.

Amines↗
PubMedDate not supplied

[Critical evaluation of P-C test parameters in screening pelvic musculature activity].

The P-C test was performed on 296 unselected women to verify if its parameters were all useful for a screening program: the 0-5 contraction strength score resulted unnecessarily too elaborated, a linear relationship was always seen between muscular endurance and contraction strength, muscular exhaustion was never detected during the testing, antagonist muscular synergies were observed only in some of the patients with low contraction strength score; marked agonist synergies were never detected. For screening purpose therefore could be sufficient to evaluate only the contraction strength identifying three levels of its activity: no activity, low activity, good activity.

Biomechanical Phenomena↗
PubMed1998

Saccadic probability influences motor preparation signals and time to saccadic initiation.

One must be prudent when selecting potential saccadic targets because the eyes can only move to one location at a time, yet movements must occur quickly enough to permit interaction with a rapidly changing world. This process of efficiently acquiring relevant targets may be aided by advanced planning of a movement toward an upcoming target whose location is gathered via environmental cues or situational experience. We studied how saccadic reaction times (SRTs) and early pretarget neuronal activity covaried as a function of saccadic probability. Monkeys performed a saccadic task in which the probability of the required saccade being directed into the response field of a neuron varied systematically between blocks of trials. We recorded simultaneously the early pretarget activity of saccade-related neurons in the intermediate layers of the superior colliculus. We found that, as the likelihood of the saccade being generated into the response field of the neuron increased, the level of neuronal activity preceding target presentation also increased. Our data suggest that this early activity codes motor preparation because its activity was related to not only the metrics but also the timing of the saccade, with 94% (29/31) of the neurons tested having significant negative correlations between discharge rate and SRT. This view is supported by cases in which exceptionally high levels of pretarget activity were associated with anticipatory saccades into the response field of a neuron that occurred in advance of the target being presented. This study demonstrates how situational experience can expedite motor behavior via the advanced preparation of motor programs.

Animals↗
PubMed2004

Applications of hierarchical linear models for evaluations of health interventions: demystifying the methods and interpretations of multilevel models.

Despite the wide availability of statistical programs designed to deal with longitudinal data from a multilevel perspective, many applied researchers remain unfamiliar with the benefits of this methodology, particularly for the evaluation of interventions. The authors present an example of multilevel modeling as part of the analysis of evaluation data from an HIV intervention study. Strategies for understanding multilevel models using longitudinal (panel) data are demonstrated and discussed. The authors illustrate how multiple linear regression models provide a convenient conceptual background to understanding how hierarchical linear models can be developed and interpreted. Multilevel analysis results are compared and contrasted with typical approaches through general linear models for repeated-measures data. Analyses are presented using the SPSS and HLM 5 software.

Analysis of Variance↗
PubMed2007

Doses and LET spectra in the beam of 12C with energy 500 MeV amu-1.

This paper describes the results of experimental studies performed at the Joint Institute for Nuclear Research (JINR) in a (12)C ion beam with the primary nominal energy 500 MeV amu(-1). Data measured by means of a diamond detector and a spectrometer of linear energy transfer (LET) based on chemically etched track detectors are presented, analysed and discussed. LET spectra are also calculated by program SRIM.

Animals↗
PubMedDate not supplied

Toward generating simpler QSAR models: nonlinear multivariate regression versus several neural network ensembles and some related methods.

In this study we want to test whether a simple modeling procedure used in the field of QSAR/QSPR can produce simple models that will be, at the same time, as accurate as robust Neural Network Ensemble (NNE) ones. We present results of application of two procedures for generating/selecting simple linear and nonlinear multiregression (MR) models: (1) method for selecting the best possible MR models (named as CROMRsel) and (2) Genetic Function Approximation (GFA) method from the Cerius2 program package. The obtained MR models are strictly compared with several NNE models. For the comparison we selected four QSAR data sets previously studied by NNE (Tetko et al. J. Chem. Inf. Comput. Sci. 1996, 36, 794-803. Kovalishyn et al. J. Chem. Inf. Comput. Sci. 1998, 38, 651-659.): (1) 51 benzodiazepine derivatives, (2) 37 carboquinone derivatives, (3) 74 pyrimidines, and (4) 31 antimycin analogues. These data sets were parameterized with 7, 6, 27, and 53 descriptors, respectively. Modeled properties were anti-pentylenetetrazole activity, antileukemic activity, inhibition constants to dihydrofolate reductase from MB1428 E. coli, and antifilarial activity, respectively. Nonlinearities were introduced into the MR models through 2-fold and/or 3-fold cross-products of initial (linear) descriptors. Then, using the CROMRsel and GFA programs (J. Chem. Inf. Comput. Sci. 1999, 39, 121-132) the sets of I (I < or = 8, in this paper) the best descriptors (according to the fit and leave-one-out correlation coefficients) were selected for multiregression models. Two classes of models were obtained: (1) linear or nonlinear MR models which were generated starting from the complete set of descriptors, and (2) nonlinear MR models which were generated starting from the same set of descriptors that was used in the NNE modeling. In addition, the descriptor selection method from CROMRsel was compared with the GFA method included in the QSAR module of the Cerius2 program. For each data set it has been found that the MR models have better cross-validated statistical parameters than the corresponding NNE models and that CROMRsel selects somewhat better MR models than the GFA method. MR models are also much simpler than NNEs, which is the important surprising fact, and, additionally, express calculated dependencies in a functional form. Moreover, MR models were shown to be better than all other models obtained by different methods on the same data sets ("old" multivariate regressions, functional-link-net models, back-propagation neural networks, genetic algorithm, and partial least squares models). This study also indicated that the robust NNE models cannot generate good models when applied on small data sets, suggesting that it is perhaps better to apply robust methods (like NNE ones) on larger data sets.

Journal Article↗
PubMed1995

A multisite study of client outcomes in assertive community treatment.

OBJECTIVE: This study examined outcomes of clients admitted to assertive community treatment programs simultaneously implemented at six sites in northeastern Indiana. METHODS: A total of 212 clients at risk for psychiatric rehospitalization were assessed at baseline and at six-month intervals for 18 months after admission to assertive community treatment programs. Data on rehospitalization, quality of life, and level of functioning were compared using t tests. Progressive improvement was also examined by linear trend analysis. RESULTS: Frequency of psychiatric hospitalization was reduced by one-third and the number of inpatient days by 50 percent after admission to the program. Improvements were progressive, with continued reductions over the 18-month period. Progressive improvements also occurred in quality of life as measured by both client and staff ratings. Case managers rated clients as having improved family and social support, increased self-reliance and independence, and improved daily living skills. Clients reported significantly more legal problems, which may have been an artifact of increased monitoring during treatment. A key element of the programs' success was the position of clinical coordinator, important functions of which are described. CONCLUSIONS: Results of this study provide support for wide-scale dissemination of assertive community treatment as an effective form of community care for persons with serious mental illness.

Activities of Daily Living↗
PubMed2004

Retention indexes for temperature-programmed gas chromatography of polychlorinated biphenyls.

A noninteger retention index was defined based on a series of PCB internal standards, namely congeners 8 (2,4'-dichlorobiphenyl), 31 (2,4',5-trichlorobiphenyl), 44 (2,2',3,5'-tetrachlorobiphenyl), 101 (2,2',4,5,5'-pentachlorobiphenyl), 138 (2,2',3,4,4',5'-hexachlorobiphenyl), 180 (2,2',3,4,4',5,5'-heptachlorobiphenyl), and 194 (2,2',3,3',4,4',5,5'-octachlorobiphenyl). These retention index markers are common congeners present in technical mixtures and most environmental samples, and they show a linear dependence of retention time on the number of chlorine atoms, in the temperature-programmed analysis. The index values are calculated with a single regression equation instead of the Van den Dool and Kratz equation. The retention indexes of all 209 PCBs on two commonly used columns (DB-XLB and DB-5), as well as on a supplementary column of DB-17 in capillary gas chromatography, were determined using this system. The reliability of the retention index is quite good, with the average 95% confidence limits for three measurements on each PCB being +/-0.1 index unit under the same chromatographic conditions and +/-0.4 index unit under different column head pressures. The effect of heating rate of the programmed runs on the retention index was also investigated. The inversion of the elution order of some congener pairs on the DB-XLB column for different temperature heating rates was observed. Our index values were compared with those of Castello and Testini.

Chromatography, Gas↗
PubMed1998

Control of grip force when tilting objects: effect of curvature of grasped surfaces and applied tangential torque.

When we manipulate objects in everyday tasks, there are variations in the shape of the grasped surfaces, and the loads that potentially destabilize the grasp include time-varying linear forces and torques tangential to the grasped surfaces. Previous studies of the control of fingertip forces for grasp stability have dealt principally with flat grip surfaces and linear force loads. Here, we studied the regulation of grip force with changes in curvature of grasped surfaces and changes in tangential torque applied by the index finger and thumb when humans lifted an object and rotated it about the horizontal grip axis through an angle of 65 degrees. The curvatures of the matched pair of spherical surfaces varied from -50 m-1 (concave with radius 20 mm) to 200 m-1 (convex with radius 5 mm). The applied tangential torque at the orientation of 65 degrees was varied sixfold. Regardless of the values of curvature and end torque, grip force and tangential torque were coordinated, increasing in parallel throughout the tilt with an approximately linear relationship; the slope of the line increased progressively with increasing surface curvature. This parametric scaling of grip force was directly related to the minimum grip force required to prevent rotational slip, resulting in an adequate safety margin against slip in all cases. We conclude that surface curvature parametrically influences grip force regulation when the digits are exposed to torsional loads. Furthermore, the sensorimotor programs that control the grip force apparently predict the effect of the total load comprising linear forces and tangential torques.

Adult↗