International Races Research Articles

Blood testing in biathlon: observation of hematocrit values during competitive periods 1994-1997.

The International Biathlon Union, through its own Medical Commission, has undertaken a three-year program aimed at identifying the hematocrit levels of athletes who participate in biathlons. The purpose was to check for hematocrit levels exceeding normal physiological values as well as for any significant modifications within individuals during the course of the competitive season. All of the athletes registered in international biathlon races were, therefore, subjected to venous blood sampling (1 cc) three times a year prior to competition, in the days preceding two World Cup races (December and January) and the World Championships (February). The blood was centrifuged, the micro-hematocrit determined, and the value (rendered anonymous) recorded. This procedure was repeated for three consecutive competitive seasons (Dec. 1994-Feb. 1995, Dec. 1995-Feb. 1996, Dec. 1996-Feb. 1997). During this three-year period, the collected data showed a significant lowering of the average hematocrit level. In fact, from the first February sampling to the third February sampling, the average hematocrit value for the male population dropped from 48.04 +/- 2.36 to 46.33 +/- 1.91, and for the female population from 44.05 +/- 2.44 to 42.52 +/- 1.92. Even the distribution of the absolute hematocrit values was modified from the first to the third competitive season, especially for the February sampling, with a > or = 50% reduction for males and a > or = 48% reduction for females.

PREDICTION OF SWIMMING COMPETTTIVE PERFORMANCE THROUGH LACTATE TESTING PROCEDURES

190 The purpose of the present study was to evaluate the interrelationship between blood lactate concentration (BLa) and swimming competitive performance. We have selected 40 international level swimming races, in order to establish the relationship between swimming performance and blood lactate concentration. Every swimmer performed a protocolar progressive lactate swimming test 48 hours after they have competed and based in the same distance and technique utilised in the race, in order to establish in each case the difference between real post-effort blood lactate concentration and post-effort blood lactate concentration predicted throughout blood lactate testing, the individual blood lactate profile accumulation (IBLPA). Blood samples were analysed by enzymatic method Boheringer Mannheim® The results of the study did not reveal any correlation between BLa and swimming competitive performance. Since it was not possible to establish a relationship between competition performance and the correspondent associated blood lactate concentration, we can conclude that blood lactate post-effort isolated values are meaningless. The IBLPA reflects a metabolic profile with no stability in temporal terms, since the specificity, based on the coefficient correlation values (Pearson, p <.05), is stronger in relation to swimming competition distances performed very near (48 hours) the protocolar determination of the IBLPA, justifying his importance in the training process monitoring. The IBLPA has a elevated predictive value in the mainly aerobic events, based in the non-significant difference between predicted and real post-effort BLa (T test). In the mainly anaerobic events we found a significant difference between predicted and real post-effort BLa (“t” paired test, p<.01), confirming that the information derived from IBLPA concerns to the aerobic adaptations of the swimmer.

Pathogenic Variability inPyricularia griseaat a Rice Blast "Hot Spot" Breeding Site in Eastern Colombia

Forty-five international races of Pyricularia grisea, representing all nine race groups, were identified in a «hot spot» breeding site (Santa Rosa) in Colombia, with the largest number included in the IA group. The international race system did not fully describe the virulence spectrum of the isolates, since several races could be further differentiated into different pathotypes when local commercial cultivars were used as differentials. Compatibility was present in the pathogen population for at least 13 known resistance genes and resistance sources tested. Frequency of virulent phenotypes on the 42 cultivars tested ranged from 0.0 to 0.86, with no cultivar susceptible to all isolates. The lowest compatibility frequencies were associated with combinations of resistance genes

Physiological and Biomechanical Aspects of Rowing

The drag force on a racing shell increases with the square of velocity corresponding to a 3.2 power increase in energy expenditure. However, the metabolic cost increases with only an approximately 2.4 power function of shell velocity. During international races the metabolic cost corresponds to an oxygen uptake of 6.7 to 7.0 L/min over 6.5 min. The relative anaerobic contribution to 6.5 min of 'all-out' rowing has not been determined but is estimated to range from 21 to 30%. Because of the large muscle mass involved in rowing, blood variables reach extreme values: adrenaline 19 nmol/L; noradrenaline 74 nmol/L; pH 7.1; and bicarbonate 9.8 mmol/L. Because of the static component of the rowing stroke at the catch, blood pressure increases to near 200mm Hg, and the heart of oarsmen has adapted to this load by increasing wall thickness and internal diameters. The maximal oxygen uptake of oarsmen may reach 6.6 L/min and ventilation 243 L/min. Arterial oxygen tension decreases by 20mm Hg during 'all-out' rowing corresponding to a decrease in pulmonary diffusion capacity. A force of approximately 800 to 900N is developed on the oar. Force generation during rowing is relatively slow, 0.3 to 0.4 sec. Oarsmen are strongest in low velocity movement with 70 to 75% slow twitch fibres in skeletal muscle. Data indicate that rowing technique and training may improve explaining why results become approximately 0.7 sec faster per year.

Pathogenic race and mating type of Pyricularia oryzae from Soviet Union, China, Nepal, Thailand, Indonesia and Colombia.

A total of 130 isolates of Pyricularia oryzae from 6 countries were tested for the identification of pathogenic race and mating type. The number of races identified from country of origin was, Soviet Union-3 Japanese races [3 international races], China-7 [9], Nepal-2 [2], Thailand-3 [2], Indonesia-4 [4], and Colombia-5 [12]. The reaction of these races identified by means of Japanese and international rice cultivars did not always correspond. About 40% of the isolates used were of untetermined pathogenic race, because of inconsistent host reaction. The phenotypic variability in pathogenic reaction could be due to the heterogeneity of the differential rice cultivars as well as to the pathogenic change of the blast fungus itself. The presence of both mating types was confirmed in the isolates from China and Colombia, but in the Russian and Nepalese collection mating type A was only detected. On the other hand, all of the Indonesian isolates used were of mating type a.

Conidium Ontogeny in Pyricularia1

AbstractConidium ontogeny of twenty‐three isolates of Pyricularia (including international races, some nutritional, coloured mutants and isolates obtained from cultivated and wild species of Gramineae) was studied. Among them, sixteen isolates were found to be of typical blastic type of conidiogenesis characteristic of the genus Pyricularia. Three coloured mutants and an international race showed gangliar type of conidiogenesis. However, two races and one nutritional mutant showed both the types.Most of the isolates tested are morphologically indistinguishable and potentially pathogenic with the respective hosts and on differential cultivars. Possible alteration of morphogenetic pattern of conidiogenesis by mutation and temperature response is suggested.

Physician Skis for Fitness, Races for Reward.

Milton Hanson was looking forward to a five-month cross-country skiing vacation, but the challenge of ski racing induced him to enter a series of international races.

A computational method for fitting Richardson equations of arms races

Several mathematical models have been developed for describing international arms races, military conflicts, and other interactions between nations. A crucial question is whether or not such equations can be fitted to actual data. If the answer is in the affirmative, then there are tremendous opportunities for prediction and planning. We present a mathematical and computational method for estimating not only parameters in dynamical models of armament races, but also a complete set of unknown initial conditions. Computational results show the comple feasibility of the quasilinearization method, but further investigation is needed to determine capabilities and limitations of this new approach.

Studies on the inheritance of leaf blast resistance in rice

Studies on the inheritance of leaf blast resistance in seven differential varieties of rice tested against two Indian isolates of the international races IA-11 add ID-1 ofPyricularia oryzae Cav. under standardized experimental conditions revealed the presence of three dominant genes, one each in Zenith. Tetep and Ginga conferring resistance to IA-11 and two, one each in Zenith and Tetep, to the race ID-1. The genes of Zenith were independent of those of Tetep. C.l. 5309 possessed inhibitory genes inhibiting the resistance of Zenith but not of Telep. Mode of segregation of resistance o Norin 20 to the race IA-11 was found to be anamolous. Studies on the crosses among susecptible varieties showed the existence of dominant genes conferring susceptibility, two each in P.I. 180061 and Yakeiko. This is a new feature of the present studies and its utility in evolving homozygous recessive resistant varieties have been pointed out.

Pedestrianism and the Struggle for the Sir John Astley Belt, 1878–1879

Abstract During the eighth decade of the nineteenth century, the American sporting scene was enriched by a series of five fabulous international pedestrian races. Sir John Astley, the English sporting baron, inaugurated the transatlantic six-day and six-night marathon races. These quintuple struggles roused nationalistic pride and sporting blood on two continents, were witnessed by tens of thousands, and resulted in feats of unprecedented human endurance.

U.S.-Japan cooperative research on the international pathogenic races of the rice blast fungus, Piricularia oryzae Cav., and their international differentials

Research studies were conducted in Japan and the United States under a 3-year cooperative project in order to select an international set of rice varieties for differentiating the pathogenic races of Piricularia oryzae. Initially, the 39 varieties comprising the former United States, Japan and Taiwan differentials were used. As the studies progressed, 12 candidate varieties were selected. A total of 59 races were differentiated through use of the 12 varieties. Eight of the 12 candidate varieties were selected as the final set of international differentiating varieties: Raminad Str. 3; Zenith; NP-125; Usen; Dular; Kanto 51; Sha-tiao-tsao-S; and Caloro. Among P. oryzae isolates from several rice-producing countries, 32 international races were characterized.

Differential reaction of potato hosts to foreign and domestic potato physiologic races of phytophthora infestans

The potato physiologic races of P. infestans and genes for resistance reported by Black in Scotland, Mastenbroek in the Netherlands, and Mills and Peterson in the United States were found to match or fall into a definite pattern of relationship. Ten distinct isolate groups identified from the reactions of the isolates on the three sets of differential hosts matched the international races 1; 2; 4; 1,2; 1.4; 2,4; 1,2.4; 1,3,4; and 2,3,4. Canadian isolates were identified as races 1,2; 1,2,3; 1,2,4; and 1,2,3,4. One West Virginia isolate was identified as race 3. These 13 different races together with 2 others (1,3 and 3,4) described by Black but not available for study, bring the total number of potato races of P. infestans found to fifteen. Only race 2,3 has not been found from the possible sixteen that can be identified on present differential hosts. The results confirm the interrelationship of genes and races reported in a joint paper by the above four authors. A few isolates gave reactions different from those described for them, but they reacted as one of the other races. Either the cultures were mis-labeled or changed while growing in pure culture. Therefore, the proposed international system of designating potato races of P. infestans and genes for resistance to these races appears to be a valid and workable one for the present.