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PubMed1979

[Lysine requirement of fattening boars in respect to their performance. 1. Influence of the consumption of energy and amino acids on the fattening performance].

With a total number of 157 boars 9 feeding variants with different levels of energy and amino acids were checked. The weight increase per fattening day and the energy and lysine expenditure per kg live weight increase were determined. The insufficient supply with lysine had negative effects on the live weight increase and the energy expenditure during the whole fattening period. Between the variantes with a high supply with amino acids (120%) and the supply according to standard (100%) no significant differences concerning the live weight increase could be ascertained up to 90 kg live weight. Between 90 and 120 kg live weight the animals in the variant with medium energy level and 120% lysine supply achieved significantly higher increases than those in the standard variant. Up to 90 kg live weight the energy expenditure for all groups amounted to 2,08 kEFs (energetic feed units for pigs) per kg live weight increase. The most suitable results were achieved by the animals which received the variants rich in energy (1,760 resp. 1,770 kEFs per kg live weight increase). Above the 90 kg live weight limit the energy expenditure rose considerably, remained however under 2,000 kEFs per kg live weight increase for the boars of the variant with medium energy level and 120% lysine supply as well as for the variant rich in energy and 100% lysine supply. The lysine expenditure in the first variant amounted to 25.1 g per kg live weight increase and for the variant rich in energy to 20.6 g lysine per kEFs.

Amino Acids↗
PubMed1976

[Studies on the strength and the cutting performance of dental canal reamer. (III) Cutting performance and torsional fracture (author's transl)].

Characteristics of cutting torque and fracture strength of pulp canal reamers are important problems as for the severity used at many of dental cutting tools. And it is the most difficult problems that reamers are cutting tools to be used for magnification of root canals. So, this paper makes a report on the measurements of reamer's section and dimension of the under hole, which are required for cutting test, and on the safety of characteristics of dental canal reamers. Diameter of under hole are determined by the relationship of reamer's section. And these results of measurements are compared with the Japanese Industrial Standard values and we discussed the probabilities of the clearance of these dimensions. Cutting torque of reamers are measured with twisting test machine of our making. Concerning the safety of fractures, we apply the theoretical analysis for the fracture to torque of bite tips and estimated the fracture torque of cutting section of reamers. And probablity of twisting fracture of reamers are existed about from one half to one-fifth values for the dental reamers of practical used.

Dental Instruments↗
PubMed1979

[Reaction performance, motor coordination performance and findings in hypertensive patients under diisopropylamine and reserpine therapy].

In 64 male hypertonics the reaction and coordination functions and the condition were standardized and compared before and after a four weeks ambulatory treatment with diisopropylamine (3 times 200 mg a day) and reserpine (3 times 0.25 mg a day). The two medicaments achieved good blood pressure reducing effects. Since in reserpine the therapeutic effect later appeared, fatigue and need for sleep were more frequent and continuous, in older patients still after a treatment of four weeks right and temporary reactions decreased, wrong reaction increased and the aim accelerated, is concluded that here in particular in the behaviour of older people more frequently a longer lasting disturbance is probable.

Adult↗
PubMed2026

Effects of Blood Flow Restriction Training at Different Levels of Arterial Occlusion Pressure on Body Composition and Athletic Performance in Youth Soccer Players: A Randomized Controlled Trial.

This study aimed to investigate the effects of low-load blood flow restriction training (BFRT) performed at different levels of arterial occlusion pressure (AOP) on body composition, maximal strength, and athletic performance in youth soccer players. Twenty-four male youth soccer players were randomly assigned to 40% AOP group, 60% AOP group, or control group. Participants in the BFRT groups performed lower-limb resistance training at 30% of one-repetition maximum (1RM) under the corresponding pressure conditions, whereas the control group trained without BFR. Training was conducted three times per week for six weeks. Body composition, back squat 1RM, countermovement jump (CMJ), T-test, and 30-m sprint performance were assessed before and after the intervention. Results showed that lower-limb muscle mass increased significantly in both the 40% AOP group (mean change = 0.55 kg, 95% CI: 0.13 to 0.97 kg, P = 0.010) and the 60% AOP group (mean change = 0.83 kg, 95% CI: 0.37 to 1.29 kg, P < 0.001), with the 60% AOP group showing significantly greater gains than the control group (between-group difference = 1.48 kg, 95% CI: 0.40 to 2.56 kg, P = 0.008). Back squat 1RM improved significantly in both the 40% AOP group (mean change = 6.50 kg, 95% CI: 3.90 to 9.10 kg, P < 0.001) and the 60% AOP group (mean change = 9.25 kg, 95% CI: 6.75 to 11.75 kg, P < 0.001), with the 60% AOP group demonstrating superior strength gains compared with the 40% AOP group (between-group difference = 2.94 kg, 95% CI: 0.20 to 5.68 kg, P = 0.048). CMJ height and T-test performance improved significantly in both the 40% AOP group (CMJ: mean change = 2.07 cm, 95% CI: 0.80 to 3.34 cm, P = 0.002; T-test: mean change = -0.23 s, 95% CI: -0.35 to -0.11 s, P = 0.001) and the 60% AOP group (CMJ: mean change = 2.65 cm, 95% CI: 1.00 to 4.30 cm, P = 0.003; T-test: mean change = -0.26 s, 95% CI: -0.38 to -0.14 s, P < 0.001), with no significant differences between the two BFRT groups (all P > 0.05). No significant changes were observed in 30-m sprint performance across groups (all P > 0.05). This study showed that six weeks of low-load (30% 1RM) blood flow restriction training performed at both 40% and 60% AOP was associated with improvements in lower-limb muscle mass, squat strength, and selected aspects of athletic performance in youth soccer players, compared with low-load training without BFR. While both pressure levels elicited comparable improvements in CMJ and agility performance, training at 60% AOP was associated with greater adaptations in lower-limb muscle mass and squat strength, with no additional benefits observed for 30-m sprint performance.

Humans↗
PubMed1979

Performance and acquisition of serial position sequences by pigeons as measures of behavioral toxicity.

A procedure has been developed to measure the repeated acquisition of serial position sequences and to study the effects of drugs and toxic chemicals on the behavior generated by the procedure. Thus far experiments using the procedure have shown: (1) Performance schedules generate lower error rates than corresponding acquisition schedules: (2) Addition of a reset contingency further decreases errors under both performance and acquisition schedules: (3) Chained acquisition and performance schedules generate lower error rates than corresponding tandem acquisition and performance schedules: (4) Chained acquisition and performance schedules produce behavior that usually is more sensitive to drugs than corresponding tandem acquisition and performance schedules: (5) Acquisition schedules produce behavior that usually is more sensitive to drugs than corresponding performance schedules: and (6) Lead is an exception in that it produced clearer effects under a chained performance schedule with a reset contingency than under a corresponding acquisition schedule. The greater sensitivity to drug effects of behavior under acquisition schedules than behavior under performance schedules and of behavior under chained schedules may be a function of the baseline error rates, rather than the behavioral processes of acquisition, performance, and stimulus control.

Animals↗
PubMed2023

Evaluating the impact of modeling choices on the performance of integrated genetic and clinical models.

The value of genetic information for improving the performance of clinical risk prediction models has yielded variable conclusions. Many methodological decisions have the potential to contribute to differential results across studies. Here, we performed multiple modeling experiments integrating clinical and demographic data from electronic health records (EHR) and genetic data to understand which decision points may affect performance. Clinical data in the form of structured diagnostic codes, medications, procedural codes, and demographics were extracted from two large independent health systems and polygenic risk scores (PRS) were generated across all patients with genetic data in the corresponding biobanks. Crohn's disease was used as the model phenotype based on its substantial genetic component, established EHR-based definition, and sufficient prevalence for model training and testing. We investigated the impact of PRS integration method, as well as choices regarding training sample, model complexity, and performance metrics. Overall, our results show that including PRS resulted in higher performance by some metrics but the gain in performance was only robust when combined with demographic data alone. Improvements were inconsistent or negligible after including additional clinical information. The impact of genetic information on performance also varied by PRS integration method, with a small improvement in some cases from combining PRS with the output of a clinical model (late-fusion) compared to its inclusion an additional feature (early-fusion). The effects of other modeling decisions varied between institutions though performance increased with more compute-intensive models such as random forest. This work highlights the importance of considering methodological decision points in interpreting the impact on prediction performance when including PRS information in clinical models.

Preprint↗
PubMed2026

The Effectiveness of Passive Half-Time Interventions on Simulated Second-Half Performance in Elite Youth Soccer Players.

The half-time period in soccer provides a potentially important window to implement short-duration interventions aimed at maintaining second-half performance. However, passive rest has been associated with a decline in subsequent physical and technical performance. While re-warm-up strategies are well studied, little is known about the efficacy of technology-based, passive recovery modalities, device-supported interventions that require minimal active movement or physical exertion from the athlete, during half-time intervals. This study examined whether percussive therapy, electrical muscle stimulation, and pneumatic compression can mitigate second-half performance decline in male adolescent soccer players. Forty-three academy-level players (17.5 &#xb1; 0.6 years) completed a simulated soccer protocol including the Loughborough Soccer Pass Test (LSPT), repeated 20-meter sprints, and completed Total Quality of Recovery (TQR) assessments before and after half-time. Participants were randomized into one of four intervention groups during the 15-minute half-time interval: Passive Rest (CON), Percussive Therapy (Theragun Pro; TG), EMS (PowerDot; PD), and Pneumatic Compression (RecoveryAir; COMP). Linear mixed-effects models assessed Time &#xd7; Condition interactions for performance and recovery outcomes. Passive half-time rest led to significant deterioration in technical skill, sprint performance, and perceived recovery (p < .05) for the control group. TG and PD significantly improved technical performance (LSPT scores) compared to the control group (d = 0.65 and 0.72, respectively; p < .01). Furthermore, TG and COMP were effective at maintaining 20-meter sprint times (d = 0.58 and 0.49; p < .01), whereas the control group experienced significant slowing. Perceived recovery (TQR) scores significantly declined in the CON group from First Half to Second Half (16.5 &#xb1; 2.2 to 11.1 &#xb1; 2.3. However, this decline was significantly attenuated in all intervention groups: TG (17.5 &#xb1; 1.9 to 14.2 &#xb1; 1.9), PD (17.3 &#xb1; 1.9 to 15.1 &#xb1; 1.9), and COMP (17.6 &#xb1; 1.9 to 15.9 &#xb1; 2.0). Short-duration passive interventions during half-time can mitigate performance decline in adolescent soccer players. TG and EMS appear most effective for preserving technical skills, while COMP may support perceived recovery. These findings highlight practical strategies for optimizing in-game performance and inform evidence-based half-time protocols.

Humans↗
PubMedDate not supplied

Behavioral correlates of denervation and reinnervation of the hippocampal formation of the rat: recovery of alternation performance following unilateral entorhinal cortex lesions.

Following unilateral lesions of the entorhinal cortex (E.C.) of the rat, cells in the dentate gyrus which have been deprived of their normal ipsilateral input are reinnervated in part by axons from the contralateral E.C. The proliferation of this crossed projection occurs largely between 8 and 12 days postlesion. The present experiments analyze changes in alternation behavior which occur during this period of afferent proliferation. Rats were trained to alternate responses (L-R) in a T-maze for food reward. Bilateral E.C. lesions resulted in a persistent deficit in alternation performance which did not recover after over 50 days of postoperative testing. Unilateral E.C. lesions, however, resulted in a transient deficit in alternation which recovered over time to preoperative levels. For example, animals permitted a 10-day recovery before the initiation of postlesion testing exhibited no more of a performance deficit than following a 10-day no-training period alone. However, animals permitted only a 3-day postoperative recovery were impaired in the alternation task until 10-12 days postlesion, despite daily training. Thus, recovery of performance following unilateral lesions was dependent on postlesion time rather than the amount of testing/retraining. Since bilateral lesions resulted in a persistent performance deficit while unilateral lesions resulted in a deficit with recovery, we hypothesize that behavioral recovery might be related to the reinnervation of the dentate gyrus by the contralateral E.C. To test this hypothesis, secondary lesions were placed in operated-recovered animals. Secondary lesions of the surviving E.C. resulted in a deficit in alternation performance similar to that following one stage bilateral lesions. In addition, secondary lesions of the dorsal psalterium (the fiber tract which carries the corssed E.C.-dentate projections) also disrupted performance in operated-recovered animals. Primary lesions of the dorsal psalterium alone had only slight and transient effects on alternation performance, however. Thus, the time course of the recovery, the results following bilateral lesions, and the results of secondary lesions are all consistent with the hypothesis that recovery of alternation performance following unilateral E.C. lesions may depend upon the reinnervation of the dentate gyrus by the contralateral E.C.

Afferent Pathways↗
PubMedDate not supplied

Peak velocities in height and mental performance. A longitudinal study of schoolchildren aged 10-14 years.

The relationship between spurts in height and in mental performance was studied by following a sample of Swedish urban schoolchildren from age 10 to 14 years. The children were grouped into early, average and late maturers with peak height velocity age (PHV age) as the criterion. A mental arithmetic test was administered once a year from grade 3 to 7 inclusive (10-14 years). Gain/year and level of performance were analysed both for a pure longitudinal sample (examined every year) and for mixed longitudinal samples. Early- and average-maturing girls had a maximum gain/year in performance about one year earlier than late-maturing girls. In boys, only early maturers seemed to have a peak in performance gain. Results from mixed longitudinal analysis indicated that gain/year curves were different for girls and boys. In level of performance, late-maturing girls were inferior to average and early maturers. No differences between maturity groups were found for boys. Girls were superior to boys in grade 5 (age 12) and grade 6 (age 13) in level of performance. Social background had a great impact on level of mental performance measured by this test. The relative influence of physical maturation and social background on level of mental performance was approximated as the ratio of the mean difference in test scores between early and late maturers to the mean difference between social group I + II and social group III. The ratio fluctuated over the grades 3 through 7; physical maturity seemed to have the greatest effect in grade 5 (age 12) for girls and in grade 7 (age 14) for boys.

Adolescent↗
PubMed1979

WAIS performance for different age groups of hypertensive and control subjects during the administration of a diuretic.

This study examined the effects of age and hypertension on WAIS performance. Previous studies have reported that hypertension adversely affects cognitive functioning, but few have considered the influence of hypertension on discrete age groups. Hypertension was found to be negatively associated with WAIS Verbal scores for younger (21 to 39 years) but not older (45 to 65 years) subjects. Further, younger subjects attained higher WAIS Performance scores than did older subjects. Medication history was not associated with performance levels for hypertensives, nor was performance of controls influenced by whether or not they were tested while on a diuretic. When WAIS Performance scores were analyzed for subjects matched on WAIS Verbal scores across age (21 to 39 vs 45 to 65 years) and blood pressure (normotensive vs hypertensive), a significant age by blood pressure interaction was found. The effect of blood pressure on Performance scores was found to be greater for younger than for older subjects. The association between plasma renin activity (PRA) level and WAIS Performance scores was also examined. Contrary to previous findings PRA was not related to Performance scores. The results are discussed in the context of previous hypertension research and their implications for comparisons across age levels.

Adult↗
PubMed1979

Effect of the antihistamines, brompheniramine maleate and triprolidine hydrochloride, on performance in man.

1 Effects of brompheniramine maleate (4 and 12 mg) and triprolidine hydrochloride (2.5 and 10 mg) on visuo-motor coordination, and on subjective assessments of performance, well-being and sleep were each studied in six subjects at 0.5, 1.5, 3.0, 5.0 and 7.0 h after ingestion. The doses refer to immediate and sustained release preparations respectively. 2. Triprolidine hydrochloride (2.5 mg) had an immediate effect on performance which persisted to 3.0 h, and the sustained release preparation (10 mg) impaired performance from 1.5 to 5.0 h. Brompheniramine maleate (4 mg) impaired performance from 1.5 to 3.0 h, and the sustained release preparation (12 mg) impaired performance at 1.5 h. There were no consistent changes in the subjective assessments of performance, or of well-being and sleep. 3. The studies emphasize the variable effects of antihistamines on performance, and suggest that effects on performance of sustained release preparations may be similar to those of the usual form. Sustained release preparations may provide an advantage in clinical practice if the antihistaminic activity is prolonged.

Adult↗
PubMed2026

Increasing gut short-chain fatty acids protects intestinal barrier function but does not spare muscle glycogen or impact aerobic performance.

Animal studies suggest gut microbiota-derived short-chain fatty acids (SCFA) provide an intestinal barrier-protecting, glycogen-sparing energy source that increases aerobic endurance performance, but confirmation in humans is needed. This study aimed to determine whether increasing colonic SCFA availability impacts intestinal barrier function, substrate metabolism, muscle glycogen and aerobic performance in healthy adults. Using a randomized, double-blind, crossover design 12 active men (age 18-30&#xa0;years;40.0&#xa0;&#xb1;&#xa0;7.1&#xa0;mL/kg/min) performed prescribed exercise and consumed a provided diet supplemented with acetylated and butyrylated high-amylose maize starch engineered to deliver SCFA to the colon (HAMS-A/B) or low-amylose maize starch (LAMS) for 7 days, separated by a 2 week washout. Indirect calorimetry, stable isotopes and blood, muscle and urine biomarkers were measured on intervention day 8 while participants completed 90&#xa0;min of steady-state cycle ergometry (ExSS; 60 &#xb1; 5%) followed by a 5&#xa0;km treadmill time trial. HAMS-A/B, relative to LAMS, increased faecal and serum SCFA. Multiple markers of intestinal barrier damage and permeability were lower, and the respiratory exchange ratio during ExSS was higher (0.02 [95% confidence interval (CI): 0.01, 0.03], Ptreatment&#xa0;<&#xa0;0.001) following HAMS-A/B versus LAMS. However no between-treatment difference in glucose turnover, muscle glycogen depletion (14&#xa0;&#xb5;mol/kg/g dry wt. [95% CI: -116, 143], Pinteractio n&#xa0;=&#xa0;0.613) or TT performance (5&#xa0;s [95%CI: -44, 54], Ptreatment&#xa0;=&#xa0;0.816) was observed. Increasing colonic and circulating SCFA modestly altered substrate oxidation and preserved intestinal barrier function during endurance exercise. However effects were not sufficient to spare muscle glycogen or increase aerobic endurance performance, leaving the practical relevance unclear and underscoring challenges inherent in translating promising preclinical findings to humans. KEY POINTS: Animal studies suggest gut microbiota-derived short-chain fatty acids (SCFA) provide an intestinal barrier-protecting, glycogen-sparing energy source that increases aerobic endurance performance, but confirmation in humans is lacking. A gut microbiota-targeted dietary supplementation strategy was used to deliver SCFA to the colon and successfully increased colonic and systemic SCFA concentrations in healthy, physically active adults before and during an endurance exercise bout and aerobic performance test. Increasing colonic and systemic SCFA availability preserved intestinal barrier function but did not impact glucose turnover, alter protein expression in muscle or spare muscle glycogen during endurance exercise. Increasing colonic and systemic SCFA availability did not impact aerobic endurance performance.

Humans↗