Govindasamy Balasekaran

Comparison of maximal oxygen consumption between black and white prepubertal and pubertal children.

The purpose of this investigation was to determine whether maximal oxygen consumption (VO2max) differed between two selected groups of black and white children and whether a difference existed to determine whether it was related to hematologic profiles, body composition, and/or physical activity/inactivity level. Forty-five prepubertal and 42 pubertal, clinically normal black and white children participated. Dual-energy x-ray absorptiometry was used to determine body composition. A computed tomography scan of the abdomen was used to determine visceral adipose tissue and s.c. adipose tissue. Daily physical activity/inactivity was assessed by questionnaire. Black prepubertal and pubertal children had lower VO2max values when compared with white children (28.8 ± 7.8 versus 35.0 ± 6.5 mL · kg−1 · min−1, p < 0.01; 33.7 ± 6.4 versus 40.4 ± 10.2 mL · kg−1 · min−1, p < 0.05; respectively). Black prepubertal and pubertal children had lower Hb concentrations ([Hb]) and hematocrits than white children (prepubertal: 12.1 ± 0.5 versus 12.8 ± 0.9 g/dL, p < 0.001; 35.6 ± 1.4 versus 37.4 ± 2.3%, p < 0.01, respectively; pubertal: 13.0 ± 0.9 versus 13.6 ± 0.7 g/dL, p < 0.05; 37.7 ± 2.5 versus 39.5 ± 2.1%, p < 0.05, respectively). In conclusion, these findings indicate that black prepubertal and pubertal children had lower VO2max when compared with their white peers matched for age, pubertal stage, and body mass index. This difference in VO2max could be attributed at least in part to comparatively lower [Hb] and more sedentary lifestyle in the black children. Further investigations should study Hb flow rate (a function of [Hb] × maximal cardiac output) in black and white children as it relates to VO2max.

Comparison of body composition with bioelectric impedance (BIA) and dual energy X-ray absorptiometry (DEXA) among Singapore Chinese.

The purpose of the study was to determine the agreement of bioelectric impedance (BIA) with dual energy X-ray absorptiometry (DEXA) among Singapore Chinese adults. Hundred subjects [63 healthy males (age: 25.2±0.5 yrs; weight: 69.7±1.9 kg; BMI: 22.8±0.4 kg m⁻²) and 37 females (age: 22.9±0.3 yrs; weight: 51.8±0.8 kg; BMI: 20.2±0.4 kg m⁻²)] were selected and body fat percentage (%BF) was measured by DEXA and BIA. Paired t test and coefficient of correlation statistics were utilized to compare the relationship between %BF(BIA) and %BF(DEXA). Bland and Altman plot was employed to investigate the agreement of %BF(BIA) with %BF(DEXA). The limits of agreement between different methods were defined as mean (M; bias)±1.96SD of the difference between the methods (95% confidence interval; CI). %BF(BIA), when compared to %BF(DEXA), revealed non-significant underestimation of %BF in females (24.1%<24.4%, p>0.05) and significant overestimation in males (15.5%<17.7%, p<0.01). There was good absolute agreement between %BF(BIA) and %BF(DEXA) among the whole cohort (1.3±6.9%) as well as among both genders (male: 2.2±6.7%, female: -0.3±6.1%) due to small mean differences between both methods. However, wider limits of agreement were revealed for %BF(BIA) among whole cohort and as well as on gender basis. The results indicate a good agreement between BIA and DEXA in measuring %BF among Singapore Chinese adults, but may not be a suitable method of measuring %BF for clinical purposes among this population due to wider limits of agreement.

RECHOKe: A Scheme for Detection, Control and Punishment of Malicious Flows in IP Networks

In this paper, we are proposing a scheme called RECHOKe (REpeatedly CHOose and keep for malicious flows, REpeatedly CHOose and Kill for non-malicious flows) to be used for detecting, controlling and punishing of malicious flows in IP networks. It is an extension of xCHOKe, CHOKe and RED-PD schemes, combining both CHOKe hit and RED drop/mark histories, to detect, control and punish these flows more accurately while providing better protection to non-malicious flows. However, unlike xCHOKe and CHOKe, RECHOKe does not drop packets during CHOKe hits; thereby eliminating the complexity of dropping or marking randomly selected packets already queued and the unreliability of CHOKe hits. We analyze xCHOKe and RECHOKe in detail using ns-2 and show that RECHOKe performs better than RED, CHOKe and xCHOKe which are limited in what they can achieve as malicious flows get much more than their fair share and non-malicious flows get mistakenly penalized.

Physiological Adaptations to Training in Competitive Swimming: A Systematic Review

Abstract The purpose of this systematic review was to summarize longitudinal studies on swimming physiology and get implications for daily practice. A computerized search of databases according to the PRISMA statement was employed. Studies were screened for eligibility on inclusion criteria: (i) present two testing points; (ii) on swimming physiology; (iii) using adult elite swimmers; (iv) no case-studies or with small sample sizes. Two independent reviewers used a checklist to assess the methodological quality of the studies. Thirty-four studies selected for analysis were gathered into five main categories: blood composition (n=7), endocrine secretion (n=11), muscle biochemistry (n=7), cardiovascular response (n=8) and the energetic profile (n=14). The mean quality index was 10.58 ± 2.19 points demonstrating an almost perfect agreement between reviewers (K = 0.93). It can be concluded that the mixed findings in the literature are due to the diversity of the experimental designs. Micro variables obtained at the cellular or molecular level are sensitive measures and demonstrate overtraining signs and health symptoms. The improvement of macro variables (i.e. main physiological systems) is limited and may depend on the athletes’ training background and experience.

Analyzing the accuracy of CHOKe hits, CHOKe misses and CHOKe-RED drops

CHOKe, xCHOKe and RECHOKe are preferential dropping schemes that have been proposed for detection, control and punishment of malicious flows at routers in IP networks. They use CHOKe hits, CHOKe misses and/or CHOKe-RED drops to carry out these tasks. In this paper we investigate the accuracy of malicious flow detection by using these hits, misses and drops (using ns-2). We also point out the unreliability of CHOKe hits and misses, when compared to CHOKe-RED drops, as they affect TCP-friendly flows adversely. By doing so, we present two variations of CHOKe called Half1 and Half2 to improve CHOKe and compare them with CHOKe. Half1 and Half2 outperform CHOKe when the combined rates of malicious flows are less or greater than the link capacity respectively.

Receiver Window Modified Random Early Detection queues with RECHOKe

In this paper, we are proposing RCUBE (Receiver Window Modified Random Early Detection queues with RECHOKe) which combines the advantages of both Receiver Window Modification (RWM) and RECHOKe schemes. By using the RECHOKe scheme, RCUBE easily identifies malicious flows by using CHOKe hit and CHOKe-RED histories, by requiring only a small amount of information, approximately proportional to the order of magnitude of malicious flows. By using the RWM scheme, we reduce the average TCP queue sizes in the queues and in doing so, not only make it easier to identify malicious flows using RECHOKe but also reduce the queuing delay resulting in significant improvements in one-way end-to-end packet delays, delay jitter, throughput and number of dropped packets for TCP-friendly flows. We analyze xCHOKe, RECHOKe and RCUBE in detail and show that RCUBE using both RWM and RECHOKe easily outperforms RED, either use alone or with RECHOKe, xCHOKe and CHOKE, in identifying, controlling and punishing malicious flows and in protecting TCP-friendly flows. Other proposed schemes either did not perform as well or incur too much overhead.

Fitness Index on Physical Fitness, Obesity and Dietary Intake of Youths in Singapore

The purpose of this study was to compare health-related fitness variables between boys and girls in Singapore. 762 and 694 13-year old Singaporean boys and girls (respectively) participated in this study. Anthropometrical measurements were taken and participants performed the Progressive Aerobic Cardiovascular Endurance Run, sit-and-reach, handgrip strength, and sit-up tests. Questionnaires regarding their lifestyle and dietary habits were also completed. Results found that boys were significantly stronger than girls, whereas girls were significantly more flexible. In general, obesity rates in Singapore are kept at a low percentage, although youths should participate in higher amounts of physical activity and exercise. It is recommended that youths consume more nutrients and reduce their intake of night snacks, desserts, and fried food in their daily diet. If this health trend continues lifelong, there may be a low risk of cardiovascular disease

Determination Of Maximal Oxygen Consumption For Different Categories Of Fitness Utilizing The Astrand Modified Running Protocol: 1664 Board #317 June 2, 8: 00 AM - 9: 30 AM.

Millions of athletes participate in the sport of track and field annually. Coaches at all levels are interested in identifying the athletes who have the potential to become top performers. While a number of tests have been used to analyze performance potential in running events, similar tests for jumping events do not exist. PURPOSE: The aim of this study was to determine whether standing vertical jump test results could be used to predict performance in long jump, triple jump, and high jump events in track and field. METHODS: Fifty-seven Division II student athletes (27 males, 34 females) agreed to participate. Pre-season vertical jump scores were recorded by coaches. Season-best performances in long jump, triple jump and high jump were collected from meet results. Regression analysis was used to determine the relationship between vertical jump and performance in the various jumping events and to develop prediction equations. Institutional Review Board (IRB) approval was granted for this study. RESULTS: Vertical jump was shown to account for 72% of the variability in the long jump, 71% of the variability in the triple jump, and 51% of the variability in the high jump. These relationships were significant (p<.01). CONCLUSIONS: There is a correlation between vertical jump scores and track and field jumping performance. While other variables will also contribute to success in the jumping events, this simple test could be used by coaches as one predictor of performance potential.

Clump Sort: A Stable Alternative to Heap Sort for Sorting Medical Data

Sorting data sets are a thoroughly researched field. Several sorting algorithms have been introduced and these include Bubble, Insertion, Selection, Shell, Quick, Merge and Heap. In this paper, we present a novel sorting algorithm,named Clump Sort, to take advantage of ordered segments already present in medical data sets. It succeeds in sorting the medical data considerably better than all the sorts except when using totally non-clumped data. In this test using totally nonclumped data, Heap sort does only slightly better than Clump sort. However, Clump sort has the advantage of being a stable sort as the original order of equal elements is preserved whereas in Heap sort, it is not since it does not guarantee that equal elements will appear in their original order after sorting. As such, Clump Sort will have considerably better data cache performance with both clumped and non-clumped data, outperforming Heap Sort on a modern desktop PC, because it accesses the elements in order. Sorting equal elements in the correct order is essential for sorting medical data.

History of the IEEE Shreveport Section, Its Struggles and Recent Revival

The IEEE Shreveport Section, a section member of IEEE Region 5, was formed in 1947. It had served engineers in Southwestern Arkansas, Northeast Texas, and North Louisiana down to Natchitoches County and is ideally defined as a small section. Geographically, it is at a disadvantage since its members are spread out throughout the section. Since its founding, the IEEE Shreveport Section struggled to exist due to its geographical disadvantage. This presentation covers the history of the IEEE Shreveport Section, its struggles and recent revival due to new initiates that are being undertaken that suits our unique situation. Keywords; IEEE Shrevport Section; History; IEEE Region 5; IEEE-USA