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The purpose of this investigation was to determine the effect of different lifting cadences on the ground reaction force (GRF) during the squat exercise. Squats performed with greater acceleration will produce greater inertial forces; however, it is not well understood how different squat cadences affect GRF. The hypotheses were that faster squat cadences would result in greater peak GRF and that the contributions of the body and barbell, both of equivalent mass, to total system inertial force would not be different. Six experienced male subjects (31 [+ or -] 4 years, 180 [+ or -] 9 cm, 88.8 [+ or -] 13.3 kg) performed 3 sets of 3 squats using 3 different cadences (fast cadence [FC] = 1-second descent/1-second ascent; medium cadence [MC] = 3-second descent/1-second ascent; and slow cadence [SC] = 4-second descent/2-second ascent) while lifting a barbell mass equal to their body mass. Ground reaction force and velocity sensor data were used to calculate inertial force contributions of both the body and barbell to total inertial force. Peak GRF were significantly higher in FC squats compared to MC (p = 0.0002) and SC (p = 0.0002). Ranges of GRF were also significantly higher in FC compared to MC (p < 0.05) and higher in MC compared to SC (p < 0.05). The inertial forces associated with the body were larger than those associated with the barbell, regardless of cadence. Faster squat cadences result in significantly greater peak GRF as a result of the inertia of the system. This study demonstrates that GRF was more dependent on descent cadence than on ascent cadence and that researchers should not use a single point on the body to approximate the location of the center of mass during squat exercise analysis. Key Words velocity, inertial forces, weight training, resistive exercise

Treadmill exercise is commonly used for aerobic and anaerobic conditioning. During nonmotorized treadmill exercise, the subject must provide the power necessary to drive the treadmill belt. The purpose of this study was to determine what factors affected the time to fatigue on a pair of nonmotorized treadmills. Twenty subjects (10 men/10 women) attempted to complete 5 minutes of locomotion during separate trials at 3.22, 4.83, 6.44, 8.05, 9.66, and 11.27 km x h(1). Total exercise time ([less than or equal to] 5 minutes) was recorded. Exercise time was converted to the number of 15-second intervals completed. Peak oxygen uptake (V[O.sub.2]) was measured using a graded exercise test on a standard treadmill, and anthropometric measures were collected from each subject before their entrance into the study. A Cox proportional hazards regression model was used to determine significant predictive factors in a multivariate analysis. Treadmill speed and absolute peak V[O.sub.2] were found to be significant predictors of exercise time, but there was no effect of anthropometric characteristics. Gender was found to be a predictor of treadmill time, but this was likely attributable to a higher peak V[O.sub.2] in men than in women. The results were not affected by the type of treadmill tested in this study. Coaches and therapists should consider the cardiovascular fitness of an athlete or client when prescribing target speed because these factors are related to the total exercise time that can be achieved on a nonmotorized treadmill.

SUMMARY Background HLAMatchmaker has been used in the Irish Blood Transfusion Service ( IBTS) to select platelets for HLA-alloimmunised, platelet refractory thrombocytopaenic patients since 2006. Although available since 2002, only three studies have been published supporting the programme's effectiveness for this indication. Objectives We sought to examine increments to HLA-matched platelets ( HMPs) at various matchmaker scores and to examine the impact of transfusing older platelets and ABO-mismatched platelets to this patient group. Methods/Materials A total of 20 consecutive HLA-alloimmunised thrombocytopaenic patients were retrospectively studied. Data collected included: pre- and post-transfusion platelet count, indication for transfusion, HLAMatchmaker score, age of unit and degree of ABO mismatch. Data were also collected on the last 3 U of ( RDPs). The Mann-Whitney U-test was used to compare increments between transfusion episodes of random donor platelets ( RDPs) vs HMPs with matchmaker scores <3, 4-7 or >8. Results Increments at <2 h were available for 63 transfusion episodes. Increments at 2-24 h were available for 93 transfusion episodes. Increments were higher when transfusing HMPs than when transfusing RDPs. Increments for HMPs that were ABO mismatched were no different than for ABO-identical units, with the exception of late increments post-transfusing HMPs with a major ABO mismatch. Age of platelets did not influence increments. Conclusion The use of HLAMatchmaker to select platelet units for thrombocytopaenic HLA-alloimmunised patients produced satisfactory platelet increments. When providing HLAMatchmaker-selected HMPs, ABO mismatch and the use of platelet units that are up to 7 days old should be permissible. [ABSTRACT FROM AUTHOR]

Congenital microvillous atrophy (CMVA) is the leading cause of neonatal secretory diarrhoea with onset either in the first 72 hours of life (early onset) or at 6-8 weeks after birth (late onset). To date over 30 cases have been reported worldwide. The prognosis for this life threatening condition continues to be poor. Therapeutic agents like somatostatin and epidermal growth factor are either ineffective or of marginal benefit. Overall five year survival after small bowel transplantation is currently approximately 50%. The following brief review is aimed towards helping neonatologists/perinatologists in the early diagnosis, and management of CMVA and in counselling the parents appropriately. [ABSTRACT FROM AUTHOR]

The article profiles Franz Julius Biltz who was a pioneer of religious group Lutheran Church-Missouri Synod. Biltz reportedly participated in the Saxon immigration as an orphan from 1838 to 1839 and served as the pastor of St. Paul's Lutheran Church in Concordia, Missouri. ALso discussed are Biltz's academic background, his role in alleviating the grief of community members, and ministry.

The protein calexcitin was originally identified in molluscan photoreceptor neurons as a 20 kDa molecule which was up-regulated and phosphorylated following a Pavlovian conditioning protocol. Subsequent studies showed that calexcitin regulates the voltage-dependent potassium channel and the calcium-dependent potassium channel as well as causing the release of calcium ions from the endoplasmic reticulum (ER) by binding to the ryanodine receptor. A crystal structure of calexcitin from the squid Loligo pealei showed that the fold is similar to that of another signalling protein, calmodulin, the N- and C-terminal domains of which are known to separate upon calcium binding, allowing interactions with the target protein. Phosphorylation of calexcitin causes it to translocate to the cell membrane, where its effects on membrane excitability are exerted and, accordingly, L. pealei calexcitin contains two protein kinase C phosphorylation sites (Thr61 and Thr188). Thr-to-Asp mutations which mimic phosphorylation of the protein were introduced and crystal structures of the corresponding single and double mutants were determined, which suggest that the C-terminal phosphorylation site (Thr188) exerts the greatest effects on the protein structure. Extensive NMR studies were also conducted, which demonstrate that the wild-type protein predominantly adopts a more open conformation in solution than the crystallographic studies have indicated and, accordingly, normal-mode dynamic simulations suggest that it has considerably greater capacity for flexible motion than the X-ray studies had suggested. Like calmodulin, calexcitin consists of four EF-hand motifs, although only the first three EF-hands of calexcitin are involved in binding calcium ions; the C-terminal EF-hand lacks the appropriate amino acids. Hence, calexcitin possesses two functional EF-hands in close proximity in its N-terminal domain and one functional calcium site in its C-terminal domain. There is evidence that the protein has two markedly different affinities for calcium ions, the weaker of which is most likely to be associated with binding of calcium ions to the protein during neuronal excitation. In the current study, site-directed mutagenesis has been used to abolish each of the three calcium-binding sites of calexcitin, and these experiments suggest that it is the single calcium-binding site in the C-terminal domain of the protein which is likely to have a sensory role in the neuron. [ABSTRACT FROM AUTHOR]