Well-formedness judgment: A comparison of offline and online performance in Broca's aphasics

0na eg rcarmitimcaal tfieca tcuorem opfr ethhee nospieornat iodneafli cdietf i(nAitiCoDn )o ft hthaet frequently co-occurs with Broca’s aphasia is above-chance performance on well-formedness judgment tasks for many syntactic constructions, but impaired performance where syntactic binding of traces to their antecedents occurs. However, the methodologies used to establish this aspect of the performance profile of the ACD have been predominantly offline. Offline well-formedness tasks entail extralinguistic processing (e.g. perception, attention, short-term memory, conscious reflection) in varying amounts and the influence of such processes on parsing mechanisms is yet to be fully established. In order to (a) further understand the role of extra-linguistic processing on parsing, and (b) gain a more direct insight into the online nature of parsing in Broca’s aphasia, 8 subjects underwent a series of wellformedness judgment investigations using both offline and online test batteries. The sentence types and error types used were motivated by three current theories about the nature of the ACD, namely, the Trace-Based Account (Grodzinsky, 2000), the Mapping Hypothesis (Linebarger et al., 1983) and Capacity proposals (e.g. Frazier & Friederici, 1991). The results from the present investigation speak directly to the three aforementioned theories and also demonstrate the important role that extralinguistic processing plays during offline assessment. The clinical implications of the different outcomes from the offline vs. online tasks are also discussed.

Comparison of adsorption capacity of p-Cresol & p-Nitrophenol by activated carbon in single and double solute

Adsorption of p-Cresol and p-Nitrophenol by untreated activated carbon in single and multisolute solutions was carried out at 301 K and at controlled pH conditions. In acidic conditions, well below the pK(a) of both solutes, it was observed that the adsorbate solubility and the electron density of aromatic rings influenced the extent of adsorption by affecting the extent of London dispersion forces. The fitted parameters obtained from single-solute Langmuir equation show that Q(max) and the adsorption affinity of carbon for the compound with low pK(a) decrease more significantly. In higher solution pH conditions, on the other hand, it was found that electrostatic forces played a significant role on the extent of adsorption. The presence of another compound decreases Q(max) and the adsorption affinity of carbon for the principal compound. The effect of pH, on the carbon surface and on the solute molecules, must be considered. Adsorption of the solute at higher pH values was found to be dependent on the concentration of anionic form of the solute. The isotherm data were fitted to the Langmuir isotherm equation for both single and double solute solutions.

Comparison of two population pharmacokinetic programs, NONMEM and P-PHARM, for tacrolimus

Objectives: To compare the population modelling programs NONMEM and P-PHARM during investigation of the pharmacokinetics of tacrolimus in paediatric liver-transplant recipients. Methods: Population pharmacokinetic analysis was performed using NONMEM and P-PHARM on retrospective data from 35 paediatric liver-transplant patients receiving tacrolimus therapy. The same data were presented to both programs. Maximum likelihood estimates were sought for apparent clearance (CL/F) and apparent volume of distribution (V/F). Covariates screened for influence on these parameters were weight, age, gender, post-operative day, days of tacrolimus therapy, transplant type, biliary reconstructive procedure, liver function tests, creatinine clearance, haematocrit, corticosteroid dose, and potential interacting drugs. Results: A satisfactory model was developed in both programs with a single categorical covariate - transplant type - providing stable parameter estimates and small, normally distributed (weighted) residuals. In NONMEM, the continuous covariates - age and liver function tests - improved modelling further. Mean parameter estimates were CL/F (whole liver) = 16.3 1/h, CL/F (cut-down liver) = 8.5 1/h and V/F = 565 1 in NONMEM, and CL/F = 8.3 1/h and V/F = 155 1 in P-PHARM. Individual Bayesian parameter estimates were CL/F (whole liver) = 17.9 +/- 8.8 1/h, CL/F (cutdown liver) = 11.6 +/- 18.8 1/h and V/F = 712 792 1 in NONMEM, and CL/F (whole liver) = 12.8 +/- 3.5 1/h, CL/F (cut-down liver) = 8.2 +/- 3.4 1/h and V/F = 221 1641 in P-PHARM. Marked interindividual kinetic variability (38-108%) and residual random error (approximately 3 ng/ml) were observed. P-PHARM was more user friendly and readily provided informative graphical presentation of results. NONMEM allowed a wider choice of errors for statistical modelling and coped better with complex covariate data sets. Conclusion: Results from parametric modelling programs can vary due to different algorithms employed to estimate parameters, alternative methods of covariate analysis and variations and limitations in the software itself.

Comparison of an ELISA and an LC/MS/MS method for measuring tacrolimus concentrations and making dosage decisions in transplant recipients

This study compared an enzyme-linked immunosorbent assay (ELISA) to a liquid chromatography-tandem mass spectrometry (LC/MS/MS) technique for measurement of tacrolimus concentrations in adult kidney and liver transplant recipients, and investigated how assay choice influenced pharmacokinetic parameter estimates and drug dosage decisions. Tacrolimus concentrations measured by both ELISA and LC/MS/MS from 29 kidney (n = 98 samples) and 27 liver (n = 97 samples) transplant recipients were used to evaluate the performance of these methods in the clinical setting. Tacrolimus concentrations measured by the two techniques were compared via regression analysis. Population pharmacokinetic models were developed independently using ELISA and LC/MS/MS data from 76 kidney recipients. Derived kinetic parameters were used to formulate typical dosing regimens for concentration targeting. Dosage recommendations for the two assays were compared. The relation between LC/MS/MS and ELISA measurements was best described by the regression equation ELISA = 1.02 . (LC/MS/MS) + 0.14 in kidney recipients, and ELISA = 1.12 . (LC/MS/MS) - 0.87 in liver recipients. ELISA displayed less accuracy than LC/MS/MS at lower tacrolimus concentrations. Population pharmacokinetic models based on ELISA and LC/MS/MS data were similar with residual random errors of 4.1 ng/mL and 3.7 ng/mL, respectively. Assay choice gave rise to dosage prediction differences ranging from 0% to 30%. ELISA measurements of tacrolimus are not automatically interchangeable with LC/MS/MS values. Assay differences were greatest in adult liver recipients, probably reflecting periods of liver dysfunction and impaired biliary secretion of metabolites. While the majority of data collected in this study suggested assay differences in adult kidney recipients were minimal, findings of ELISA dosage underpredictions of up to 25% in the long term must be investigated further.

Ultra-high-temperature (UHT) treatment of milk: comparison of direct and indirect modes of heating

UHT processing of milk and its subsequent storage causes several changes which affect the shelf-life of UHT milk although it remains 'commercially sterile'. These changes include whey protein denaturation, protein-protein interaction, lactose-protein interaction, isomerisation of lactose, Maillard browning, sulphydryl compound formation, formation of a range of carbonyl and other flavoursome compounds, and formation of insoluble substances. They ultimately reduce the quality and limit the shelf life of UHT milk through development of off-flavours, fat separation, age gelation and sedimentation. The extent of these changes depends on many factors, a major one being the type of UHT heating. This review compares the effect heating milk by direct and indirect modes on various aspects of processing and quality of UHT milk.

EMG activity of trunk muscles and torque output during isometric axial rotation exertion: a comparison between back pain patients and matched controls

Abnormal patterns of trunk muscle activity could affect the biomechanics of spinal movements and result in back pain. The present study aimed to examine electromyographic (EMG) activity of abdominal and back muscles as well as triaxial torque output during isometric axial rotation at different exertion levels in back pain patients and matched controls. Twelve back pain patients and 12 matched controls performed isometric right and left axial rotation at 100%, 70%, 50%, and 30% maximum voluntary contractions in a standing position. Surface EMG activity of rectus abdominis, external oblique, internal oblique, latissimus dorsi, iliocostalis lumborum and multifidus were recorded bilaterally. The primary torque in the transverse plane and the coupling torques in sagittal and coronal planes were measured. Results showed that there was a trend (P = 0.08) of higher flexion coupling torque during left axial rotation exertion in back pain patients. Higher activity for external oblique and lower activity for multifidus was shown during left axial rotation exertion in back pain group when compared to the control group. In right axial rotation, back pain patients exhibited lesser activity of rectus abdominis at higher levels of exertion when compared with matched controls. These findings demonstrated that decreased activation of one muscle may be compensated by overactivity in other muscles. The reduced levels of activity of the multifidus muscle during axial rotation exertion in back pain patients may indicate that spinal stability could be compromised. Future studies should consider these alternations in recruitment patterns in terms of spinal stability and internal loading. The findings also indicate the importance of training for coordination besides the strengthening of trunk muscles during rehabilitation process. (C) 2002 Orthopaedic Research Society. Published by Elsevier Science Ltd. All rights reserved.

Comparison of lumbar range of movement and lumbar lordosis in back pain patients and matched controls

Inconclusive findings have been shown in previous studies comparing lumbar range of movement (LROM) and lumbar lordosis between back pain patients and healthy subjects. In these studies, confounding variables such as age, gender, height, obesity, and pain level were usually not well controlled. The present study aimed to compare LROM and lumbar lordosis between back pain patients and matched controls. Fifteen male back pain patients and 15 age-, height-, obesity-, and physical activity-matched male controls were investigated. To minimize the effect of pain on the measurements, only patients with minimal or no pain at the time of testing were included in the study. Inclinometer technique was used for the evaluation of LROM in flexion, extension and lateral flexion as well as lumbar lordosis. A lumbar rotameter was used for measuring axial rotation. Pelvic motion was limited by a pelvic restraint device during LROM measurements. Results showed that there were no significant differences between the back pain and control groups in flexion, extension, lateral flexion and axial rotation LROM and also in lumbar lordosis. This may indicate that when a back pain patient is not in pain, LROM and lumbar lordosis may not be the measures that distinguish between back pain patients and subjects without back pain.

Comparison between human and animal isolates of Shiga toxin-producing Escherichia coli O157 from Australia

There is very little human disease associated with enterohaemorrhagic Escherichia coli O157 in Australia even though these organisms are present in the animal population. A group of Australian isolates of E. coli O157:H7 and O157:H- from human and animal sources were tested for the presence of virulence markers and compared by XbaI DNA macrorestriction analysis using pulsed-field gel electrophoresis (PFGE). Each of 102 isolates tested contained the gene eae which encodes the E. coli attaching and effacing factor and all but one carried the enterohaemolysin gene, ehxA, found on the EHEC plasmid. The most common Shiga toxin gene carried was stx(2c), either alone (16%) or in combination with stx(1) (74%) or stx(2) (3%) PFGE grouped the isolates based on H serotype and some clusters were source specific. Australian E. coli O157:H7 and H- isolates from human, animal and meat sources carry all the virulence markers associated with EHEC disease in humans therefore other factors must be responsible for the low rates of human infection in Australia.

Mathematical modelling of schistosomiasis japonica: comparison of control strategies in the People's Republic of China

We present the first mathematical model on the transmission dynamics of Schistosoma japonicum. The work extends Barbour's classic model of schistosome transmission. It allows for the mammalian host heterogeneity characteristic of the S. japonicum life cycle, and solves the problem of under-specification of Barbour's model by the use of Chinese data we are collecting on human-bovine transmission in the Poyang Lake area of Jiangxi Province in China. The model predicts that in the lake/marshland areas of the Yangtze River basin: (1) once-early mass chemotherapy of humans is little better than twice-yearly mass chemotherapy in reducing human prevalence. Depending on the heterogeneity of prevalence within the population, targeted treatment of high prevalence groups, with lower overall coverage, can be more effective than mass treatment with higher overall coverage. Treatment confers a short term benefit only, with prevalence rising to endemic levels once chemotherapy programs are stopped (2) depending on the relative contributions of bovines and humans, bovine treatment can benefit humans almost as much as human treatment. Like human treatment, bovine treatment confers a short-term benefit. A combination of human and bovine treatment will dramatically reduce human prevalence and maintains the reduction for a longer period of time than treatment of a single host, although human prevalence rises once treatment ceases; (3) assuming 75% coverage of bovines, a bovine vaccine which acts on worm fecundity must have about 75% efficacy to reduce the reproduction rate below one and ensure mid-term reduction and long-term elimination of the parasite. Such a vaccination program should be accompanied by an initial period of human treatment to instigate a short-term reduction in prevalence, following which the reduction is enhanced by vaccine effects; (4) if the bovine vaccine is only 45% efficacious (the level of current prototype vaccines) it will lower the endemic prevalence, but will not result in elimination. If it is accompanied by an initial period of human treatment and by a 45% improvement in human sanitation or a 30% reduction in contaminated water contact by humans, elimination is then possible. (C) 2002 Elsevier Science B.V. All rights reserved.