Analysis of a new cross flow heat exchanger flow arrangement - Extension to several rows

The present paper presents a theoretical analysis of a cross flow heat exchanger with a new flow arrangement comprehending several tube rows. The thermal performance of the proposed flow arrangement is compared with the thermal performance of a typical counter cross flow arrangement that is used in chemical, refrigeration, automotive and air conditioning industries. The thermal performance comparison has been performed in terms of the following parameters: heat exchanger effectiveness and efficiency, dimensionless entropy generation, entransy dissipation number, and dimensionless local temperature differences. It is also shown that the uniformity of the temperature difference field leads to a higher thermal performance of the heat exchanger. In the present case this is accomplished thorough a different organization of the in-tube fluid circuits in the heat exchanger. The relation between the recently introduced "entransy dissipation number" and the conventional thermal effectiveness has been obtained in terms of the "number of transfer units". A case study has been solved to quantitatively to obtain the temperature difference distribution over two rows units involving the proposed arrangement and the counter cross flow one. It has been shown that the proposed arrangement presents better thermal performance regardless the comparison parameter. (C) 2012 Elsevier Masson SAS. All rights reserved.

A comparison of time-motion performance between age groups in judo matches

The aim of this study was to compare time-motion indicators during judo matches performed by athletes from different age groups. The following age groups were analysed: Pre-Juvenile (13-14 years, n=522), Juvenile (15-16 years, n 353); Junior (19 years, n = 349) and Senior (>20 years, n = 587). The time-motion indicators included: Total Combat Time, Standing Combat Time, Displacement Without Contact, Gripping Time, Groundwork Combat Time and Pause Time. Analysis of variance (ANOVA) one-way and the Tukey test, as well as the Kruskal-Wallis test and Mann-Whitney (for non-parametric data), were conducted, using P < 0.05 as significance level. The results showed that all analysed groups obtained a median of 7 (first quantile - 3, third quantile - 12) sequences of combat/pause cycles. In total time of combat, the result was: for Total Combat Time, Standing Combat Time and Gripping Time: Pre-Juvenile and Senior were significantly longer than Juvenile and Junior. Considering Displacement Without Contact, Junior was significantly longer than all other age groups. For Groundwork Combat Time, Senior was significantly longer than all other age groups and Pre-Juvenile was longer than Junior. These results can be used to improve the physiological performance in intermittent practices, as well as technicaltactical training during judo sessions.

Development and validation of a simple and sensitive high performance liquid chromatographic method for the simultaneous determination of anastrozole, bicalutamide, tamoxifen, and their synthetic impurities

A simple and sensitive analytical method for simultaneous determination of anastrozole, bicalutamide, and tamoxifen as well as their synthetic impurities, anastrozole pentamethyl, bicalutamide 3-fluoro-isomer, and tamoxifen e-isomer, was developed and validated by using high performance liquid chromatography (HPLC). The separation was achieved on a Symmetry (R) C-8 column (100 x 4.6 mm i.d., 3.5 mu m) at room temperature (+/- 24 degrees C), with a mobile phase consisting of acetonitrile/water containing 0.18% N,N dimethyloctylamine and pH adjusted to 3.0 with orthophosphoric acid (46.5/53.5, v/v) at a flow rate of 1.0 mL min(-1) within 20 min. The detection was made at a wavelength of 270 nm by using ultraviolet (UV) detector. No interference peaks from excipients and relative retention time indicated the specificity of the method. The calibration curve showed correlation coefficients (r) > 0.99 calculated by linear regression and analysis of variance (ANOVA). The limit of detection (LOD) and limit of quantitation (LOQ), respectively, were 2.2 and 6.7 mu g mL(-1) for anastrozole, 2.61 and 8.72 mu g mL(-1) for bicalutamide, 2.0 and 6.7 mu g mL(-1) for tamoxifen, 0.06 and 0.22 mu g mL(-1) for anastrozole pentamethyl, 0.02 and 0.07 mu g mL(-1) for bicalutamide 3-fluoro-isomer, and 0.002 and 0.007 mu g mL(-1) for tamoxifen e-isomer. Intraday and interday relative standard deviations (RSDs) were <2.0% (drugs) and <10% (degradation products) as well as the comparison between two different analysts, which were calculated by f test. (C) 2012 Elsevier B.V. All rights reserved.

Do muscle strengthening exercises improve performance in the 6-minute walk test in postmenopausal women?

Background: Walking speed seems to be related to aerobic capacity, lower limb strength, and functional mobility, however it is not clear whether there is a direct relationship between improvement in muscle strength and gait performance in early postmenopausal women. Objective: To evaluate the effect of muscle strengthening exercises on the performance of the 6-minute walk test in women within 5 years of menopause. Methods: The women were randomized into control group (n=31), which performed no exercise, and exercise group (n=27), which performed muscle strengthening exercises. The exercises were performed twice a week for 3 months. The exercise protocol consisted of warm-up, stretching, and strengthening of the quadriceps, hamstring, calf, tibialis anterior, gluteus maximus, and abdominal muscles, followed by relaxation. Muscular strength training started with 60% of 1MR (2 series of 10-15 repetitions), reaching 85% until the end of the 3-month period (4 series of 6 repetitions each). Results: The between-group comparisons pre- and post-intervention did not show any difference in distance walked, heart rate or blood pressure (p>0.05), but showed differences in muscle strength post-intervention, with the exercise group showing greater strength (p<0.05). In the within-group comparison, there were differences in final heart rate and quadriceps and hamstring strength pre- and post-intervention in the exercise group (p<0.05). Conclusion: The results suggest that muscle strengthening of the lower limbs did not improve performance in the 6-minute walk test in this population of postmenopausal women. Trial registration ACTRN12609001053213.

Comparison of Celsior and Perfadex lung preservation solutions in rat lungs subjected to 6 and 12 hours of ischemia using an ex-vivo lung perfusion system

OBJECTIVE: This study evaluated the performance of lungs that were preserved with different solutions (Celsior, Perfadex or saline) in an ex vivo rat lung perfusion system. METHODS: Sixty Wistar rats were anesthetized, anticoagulated and randomized into three groups (n = 20). The rats were subjected to antegrade perfusion via the pulmonary artery with Perfadex, Celsior, or saline, followed by 6 or 12 hours of ischemia (4 degrees C, n = 10 in each group). Respiratory mechanics, gas exchange and hemodynamics were measured at 10-minute intervals during the reperfusion of heart-lung blocks in an ex vivo system (IL2-Isolated Perfused Rat or Guinea Pig Lung System, Harvard Apparatus, Holliston, Massachusetts, USA; Hugo Sachs Elektronik, Germany) for 60 minutes. The lungs were prepared for histopathology and evaluated for edema following reperfusion. Group comparisons were performed using ANOVA and the Kruskal-Wallis test with a 5% level of significance. RESULTS: Gas exchange was not significantly different between lungs perfused with either Perfadex or Celsior at the same ischemic times, but it was very low in lungs that were preserved with saline. Airway resistance was greater in the lungs that were preserved for 12 hours. Celsior lungs that were preserved for 6 and 12 hours exhibited lower airway resistance (p = 0.01) compared to Perfadex lungs. Pulmonary artery pressure was not different between the groups, and no significant differences in histopathology and apoptosis were observed between the groups. CONCLUSIONS: Lungs that were preserved with Celsior or Perfadex exhibited similar gas exchange and histopathological findings. Airway resistance was slightly lower in the Celsior-preserved lungs compared with the Perfadex-preserved lungs.

Study of using marker assisted selection on a beef cattle breeding program by model comparison

A data set of a commercial Nellore beef cattle selection program was used to compare breeding models that assumed or not markers effects to estimate the breeding values, when a reduced number of animals have phenotypic, genotypic and pedigree information available. This herd complete data set was composed of 83,404 animals measured for weaning weight (WW), post-weaning gain (PWG), scrotal circumference (SC) and muscle score (MS), corresponding to 116,652 animals in the relationship matrix. Single trait analyses were performed by MTDFREML software to estimate fixed and random effects solutions using this complete data. The additive effects estimated were assumed as the reference breeding values for those animals. The individual observed phenotype of each trait was adjusted for fixed and random effects solutions, except for direct additive effects. The adjusted phenotype composed of the additive and residual parts of observed phenotype was used as dependent variable for models' comparison. Among all measured animals of this herd, only 3160 animals were genotyped for 106 SNP markers. Three models were compared in terms of changes on animals' rank, global fit and predictive ability. Model 1 included only polygenic effects, model 2 included only markers effects and model 3 included both polygenic and markers effects. Bayesian inference via Markov chain Monte Carlo methods performed by TM software was used to analyze the data for model comparison. Two different priors were adopted for markers effects in models 2 and 3, the first prior assumed was a uniform distribution (U) and, as a second prior, was assumed that markers effects were distributed as normal (N). Higher rank correlation coefficients were observed for models 3_U and 3_N, indicating a greater similarity of these models animals' rank and the rank based on the reference breeding values. Model 3_N presented a better global fit, as demonstrated by its low DIC. The best models in terms of predictive ability were models 1 and 3_N. Differences due prior assumed to markers effects in models 2 and 3 could be attributed to the better ability of normal prior in handle with collinear effects. The models 2_U and 2_N presented the worst performance, indicating that this small set of markers should not be used to genetically evaluate animals with no data, since its predictive ability is restricted. In conclusion, model 3_N presented a slight superiority when a reduce number of animals have phenotypic, genotypic and pedigree information. It could be attributed to the variation retained by markers and polygenic effects assumed together and the normal prior assumed to markers effects, that deals better with the collinearity between markers. (C) 2012 Elsevier B.V. All rights reserved.

Comparison of ultrasonography and histopathology for the diagnosis of endometritis in Holstein-Friesian cows

Reproductive diseases are a great barrier to dairy production, as they diminish fertility and cause economic loss. In this context, endometritis plays an important role. Different diagnostic techniques exist for endometritis that vary in sensitivity and specificity. This work aimed to evaluate and compare ultrasonographic and histopathological examinations, and combinations thereof, for the diagnosis of endometritis by determining their sensitivity, specificity, and kappa agreement coefficients using endometrial cytology as the gold standard. We developed an adaptive reading score to perform histological examination of the uterus. In this study, 76 Holstein-Friesian cows, 21 to 47 d postpartum, without vaginal catarrh were submitted to gynecological examinations, including ultrasonographic examination, an endometrial cytology examination, and a uterine biopsy. Our results indicate that ultrasonography is a practical and effective diagnostic method, and a combination of the determination of intrauterine fluid and cervical diameter was the most efficient ultrasonographic method, with 50% sensitivity and 88% specificity. Histopathological examination was a useful diagnostic method that provided rich detail on endometrial inflammation, and allowed evaluation of different components of the tissue such as the epithelium, lamina propria, endometrial glands, and blood vessels; this method had 44% sensitivity and 92% specificity for diagnosis of endometritis.

Quantitative comparison of mobility and gross motor function in Brazilian children with cerebral palsy

Background: Cerebral palsy (CP) presents changes in posture and movement as a core characteristic, which requires therapeutic monitoring during the habilitation or rehabilitation of children. Besides clinical treatment, it is fundamental that professionals use systems of evaluation to quantify the difficulties presented to the individual and assist in the organization of a therapeutic program. The aim of this study was to quantitatively verify the performance of children with spastic di-paresia type CP. Methods: The Pediatric Evaluation of Disability Inventory (PEDI) and Gross Motor Function Classification System (GMFM) tests were used and classification made through the GMFCS in the assessment of 7 patients with CP, 4 females and 3 males, average age of 9 years old. Results: According to GMFCS scales, 17% (n=1) were level II and 83% (n=6) were level III. The PEDI test and 88 GMFM items were used in the area of mobility. We observed that there was high correlation between mobility and gross motor function with Pearson's correlation coefficient =0.929) showing the likely impact of these areas in the functional skills and the quality of life of these patients. Conclusion: We suggest the impact of the limitation of the areas in functional skills and quality of life of these patients.

Comparison of multiple-input single-output single-user ultra-wideband systems with pre-distortion

This paper presents a performance analysis of a baseband multiple-input single-output ultra-wideband system over scenarios CM1 and CM3 of the IEEE 802.15.3a channel model, incorporating four different schemes of pre-distortion: time reversal, zero-forcing pre-equaliser, constrained least squares pre-equaliser, and minimum mean square error pre-equaliser. For the third case, a simple solution based on the steepest-descent (gradient) algorithm is adopted and compared with theoretical results. The channel estimations at the transmitter are assumed to be truncated and noisy. Results show that the constrained least squares algorithm has a good trade-off between intersymbol interference reduction and signal-to-noise ratio preservation, providing a performance comparable to the minimum mean square error method but with lower computational complexity. Copyright (C) 2011 John Wiley & Sons, Ltd.

Comparison between multiple sets and half-pyramid resistance exercise bouts for muscle damage profile

The present study compared the changes in markers of muscle damage after bouts of resistance exercise employing the Multiple-sets (MS) and Half-pyramid (HP) training systems. Ten healthy men (26.1 +/- 6.3 years), who had been involved in regular resistance training, performed MS and HP bouts, 14 days apart, in a randomised, counter-balanced manner. For the MS bout, participants performed three sets of maximum repetitions at 75%-1RM (i.e. 75% of a One Repetition Maximum) for the three exercises, starting with the bench press, followed by pec deck and decline bench press. For the HP bout, the participants performed three sets of maximum repetitions with 67%-1RM, 74%-1RM and 80%-1RM for the first, second and third sets, respectively, for the same three exercise sequences as the MS bout. The total volume of load lifted was equated between both bouts. Muscle soreness, plasma creatine kinase (CK) activity, myoglobin (Mb) and C-reactive protein (CRP) concentrations were assessed before and for three days after each exercise bout, and the changes over time were compared between MS and HP using two-way repeated measures ANOVA. Muscle soreness developed significantly (P<0.01) after both bouts, but no significant difference was observed between MS and HP. Plasma CK activity and Mb concentration increased significantly (P<0.01) without significant differences between bouts, and CRP concentration did not change significantly after either bout. These results suggest that the muscle damage profile is similar for MS and HP, probably due to the similar total volume of load lifted.

Reliability in kimono grip strength tests and comparison between elite and non-elite Brazilian jiu-jitsu players

Background and Study Aim: The grip strength endurance is important for Brazilian Jiu-Jitsu (BJJ). Thus, the aims of this study were: a) to test the reliability of two kimono grip strength tests named maximum static lift (MSL) and maximum number of repetitions (MNR) and b) to examine differences between elite and non-elite BJJ players in these tests. Material/Methods: Thirty BJJ players participated into two phases: "A" to test reliability and "B" to compare elite and non-elite. In phase A, twenty participants performed the MSL and, 15 min later, the MNR in two occasions with 24-h interval. In phase B, ten other BJJ practitioners (non-elite) and ten athletes (elite) performed the same tests. The intraclass correlation coefficient (ICC) two way fixed model (3,1), Bland-Altman plot and the limits of agreement were used to test reliability, correlation between the tests were evaluated by Pearson correlations and independent T test (P<0.05) was utilized to compare elite vs. non-elite. Results: The ICC was high for repeated measurements on different days of phase A (MSL: r=0.99 and MNR: r=0.97). Limits of agreement for time of suspension were -6.9 to 2.4-s, with a mean difference of -2.3 s (CI: -3.3 to -1.2-s), while for number of repetitions the limits of agreement were -2.9 to 2.3-rep, with a mean difference of -0.3-rep (CI: -0.9 to 0.3-rep). In phase B, elite presented better performance for both tests (P<0.05) compared to non-elite (56 +/- 10-s vs. 37 +/- 11-s in MSL and 15 +/- 4-rep vs. 8 +/- 3-rep in MNR). Moderate correlation were found between MSL and MNR for absolute values during test (r=0.475; p=0.034), and retest phases (r=0.489; p=0.029), while moderate and high correlations in the test (r=0.615; p=0.004) and retest phases (r=0.716; p=0.001) were found for relative values, respectively. Conclusions: These proposed tests are reliable and both static and dynamic grip strength endurance tests seem to differentiate BJJ athletes from different levels.

Selection of early-maturing sweet orange cultivars by performance indexes

The objective of this work was to select adequate early-maturing sweet orange cultivars for the fresh fruit market and for industrial processing using performance indexes. Performance indexes for citrus were established from data collected in an experiment carried out in the southwest region of the state of Sao Paulo, involving 12 early-maturing sweet orange cultivars. New results were obtained by identifying cultivars with superior characteristics. In a comparison with 'Hamlin' sweet orange, a standard early-maturing cultivar, 'Valencia 2' and 'Salustiana' were considered better materials for the fresh fruit market, whereas 'Westin' sweet orange was identified as a superior cultivar for orange juice processing.

Effects of acute physical exercise on executive functions: a comparison between aerobic and strength exercise

The aim of this study was to compare the effects of acute aerobic and strength exercises on selected executive functions. A counterbalanced, crossover, randomized trial was performed. Forty-two healthy women were randomly submitted to three different conditions: (1) aerobic exercise, (2) strength exercise, and (3) control condition. Before and after each condition, executive functions were measured by the Stroop Test and the Trail Making Test. Following the aerobic and strength sessions, the time to complete the Stroop "non-color word" and "color word" condition was lower when compared with that of the control session. The performance in the Trail Making Test was unchanged. In conclusion, both acute aerobic and strength exercises improve the executive functions. Nevertheless, this positive effect seems to be task and executive function dependent.

A novel XML document structure comparison framework based-on sub-tree commonalities and label semantics

XML similarity evaluation has become a central issue in the database and information communities, its applications ranging over document clustering, version control, data integration and ranked retrieval. Various algorithms for comparing hierarchically structured data, XML documents in particular, have been proposed in the literature. Most of them make use of techniques for finding the edit distance between tree structures, XML documents being commonly modeled as Ordered Labeled Trees. Yet, a thorough investigation of current approaches led us to identify several similarity aspects, i.e., sub-tree related structural and semantic similarities, which are not sufficiently addressed while comparing XML documents. In this paper, we provide an integrated and fine-grained comparison framework to deal with both structural and semantic similarities in XML documents (detecting the occurrences and repetitions of structurally and semantically similar sub-trees), and to allow the end-user to adjust the comparison process according to her requirements. Our framework consists of four main modules for (i) discovering the structural commonalities between sub-trees, (ii) identifying sub-tree semantic resemblances, (iii) computing tree-based edit operations costs, and (iv) computing tree edit distance. Experimental results demonstrate higher comparison accuracy with respect to alternative methods, while timing experiments reflect the impact of semantic similarity on overall system performance.

A General Latent Class Model for Performance Evaluation of Diagnostic Tests in the Absence of a Gold Standard: An Application to Chagas Disease

We propose a new general Bayesian latent class model for evaluation of the performance of multiple diagnostic tests in situations in which no gold standard test exists based on a computationally intensive approach. The modeling represents an interesting and suitable alternative to models with complex structures that involve the general case of several conditionally independent diagnostic tests, covariates, and strata with different disease prevalences. The technique of stratifying the population according to different disease prevalence rates does not add further marked complexity to the modeling, but it makes the model more flexible and interpretable. To illustrate the general model proposed, we evaluate the performance of six diagnostic screening tests for Chagas disease considering some epidemiological variables. Serology at the time of donation (negative, positive, inconclusive) was considered as a factor of stratification in the model. The general model with stratification of the population performed better in comparison with its concurrents without stratification. The group formed by the testing laboratory Biomanguinhos FIOCRUZ-kit (c-ELISA and rec-ELISA) is the best option in the confirmation process by presenting false-negative rate of 0.0002% from the serial scheme. We are 100% sure that the donor is healthy when these two tests have negative results and he is chagasic when they have positive results.