Human Force Exertion: The Significance of the Measure?

1989 ◽  
Vol 33 (18) ◽  
pp. 1201-1205 ◽  
Author(s):  
P. Y. Hennion ◽  
R. Mollard ◽  
A. Coblentz
Keyword(s):  
Basic Research ◽  
General Purpose ◽  
Individual Variability ◽  
Lower Limbs ◽  
Standard Protocol ◽  
Time Duration ◽  
Acceptable Solution ◽  
Young Males ◽  
Torque Wrench ◽  
The Stability

A basic research was conducted on a sample of twelve right-handed young males for pull actions of the upper limb on a gauge handle. The general purpose is to constitute an atlas of forces for french males, useful for ergonomics studies. Different conditions were tested before to select a standard protocol. Main difficulties concern the elimination of lower limbs contribution, the stability of the posture, the motivation of the subject and the choice of the parameters for the measure. Intra-individual variability in function of the protocols is in a range of 20-30%. With the usual standard protocol, this variability still remains if we try to evaluate maximal pull force during a week period. The interpretation of these data is not clear, and a more accurate definition of the measure is necessary before recommendations for normative data. Time duration of 5 seconds, real-time display of the force and maximal peak value seem to be an acceptable solution by comparison with a functional effort on a torque wrench that reflects a realistic action. It is proposed to use this procedure for the next experiments.

scholarly journals Influence of study model, baseline catalytic concentrations and analytical system on the stability of serum alanine aminotransferase

2020 ◽  
Vol 1 (2) ◽  
Author(s):  
Josep Miquel Bauça ◽  
Andrea Caballero ◽  
Carolina Gómez ◽  
Débora Martínez-Espartosa ◽  
Isabel García del Pino ◽  
...  
Keyword(s):  
Alanine Aminotransferase ◽  
Experimental Models ◽  
Individual Variability ◽  
Serum Samples ◽  
Multicentric Study ◽  
Different Temperatures ◽  
The Stability ◽  
Analytical System ◽  
Definition Of ◽  
Analytical Platforms

AbstractObjectivesThe stability of the analytes most commonly used in routine clinical practice has been the subject of intensive research, with varying and even conflicting results. Such is the case of alanine aminotransferase (ALT). The purpose of this study was to determine the stability of serum ALT according to different variables.MethodsA multicentric study was conducted in eight laboratories using serum samples with known initial catalytic concentrations of ALT within four different ranges, namely: <50 U/L (<0.83 μkat/L), 50–200 U/L (0.83–3.33 μkat/L), 200–400 U/L (3.33–6.67 μkat/L) and >400 U/L (>6.67 μkat/L). Samples were stored for seven days at two different temperatures using four experimental models and four laboratory analytical platforms. The respective stability equations were calculated by linear regression. A multivariate model was used to assess the influence of different variables.ResultsCatalytic concentrations of ALT decreased gradually over time. Temperature (−4%/day at room temperature vs. −1%/day under refrigeration) and the analytical platform had a significant impact, with Architect (Abbott) showing the greatest instability. Initial catalytic concentrations of ALT only had a slight impact on stability, whereas the experimental model had no impact at all.ConclusionsThe constant decrease in serum ALT is reduced when refrigerated. Scarcely studied variables were found to have a significant impact on ALT stability. This observation, added to a considerable inter-individual variability, makes larger studies necessary for the definition of stability equations.

scholarly journals Multi-year analyses on three populations reveal the first stable QTLs for tolerance to rain-induced fruit cracking in sweet cherry (Prunus avium L.)

2021 ◽  
Vol 8 (1) ◽  
Author(s):  
José Quero-García ◽  
Philippe Letourmy ◽  
José Antonio Campoy ◽  
Camille Branchereau ◽  
Svetoslav Malchev ◽  
...  
Keyword(s):  
Confidence Intervals ◽  
Sweet Cherry ◽  
Prunus Avium ◽  
Linear Models ◽  
Basic Research ◽  
Fruit Weight ◽  
Phenotypic Variance ◽  
Fruit Cracking ◽  
The Stability ◽  
Sweet Cherry Cultivars

AbstractRain-induced fruit cracking is a major problem in sweet cherry cultivation. Basic research has been conducted to disentangle the physiological and mechanistic bases of this complex phenomenon, whereas genetic studies have lagged behind. The objective of this work was to disentangle the genetic determinism of rain-induced fruit cracking. We hypothesized that a large genetic variation would be revealed, by visual field observations conducted on mapping populations derived from well-contrasted cultivars for cracking tolerance. Three populations were evaluated over 7–8 years by estimating the proportion of cracked fruits for each genotype at maturity, at three different areas of the sweet cherry fruit: pistillar end, stem end, and fruit side. An original approach was adopted to integrate, within simple linear models, covariates potentially related to cracking, such as rainfall accumulation before harvest, fruit weight, and firmness. We found the first stable quantitative trait loci (QTLs) for cherry fruit cracking, explaining percentages of phenotypic variance above 20%, for each of these three types of cracking tolerance, in different linkage groups, confirming the high complexity of this trait. For these and other QTLs, further analyses suggested the existence of at least two-linked QTLs in each linkage group, some of which showed confidence intervals close to 5 cM. These promising results open the possibility of developing marker-assisted selection strategies to select cracking-tolerant sweet cherry cultivars. Further studies are needed to confirm the stability of the reported QTLs over different genetic backgrounds and environments and to narrow down the QTL confidence intervals, allowing the exploration of underlying candidate genes.

Optimal Design of the Large-Diameter Spinning Torispherical Head

2012 ◽  
Vol 544 ◽  
pp. 194-199
Author(s):  
Di Zhang ◽  
Shui Ping Sheng ◽  
Zeng Liang Gao
Keyword(s):  
Finite Element ◽  
Optimal Design ◽  
Large Diameter ◽  
General Purpose ◽  
Design Tool ◽  
Crown Area ◽  
Finite Element Software ◽  
The Stability

Two important parameters of torispherical head that are (interior radius of spherical crown area) and r (interior radius of transition corner) have been optimized by the module of the large general-purpose finite-element software ANSYS, targeting the strength and stability of the head. This paper provides an optimized torispherical head, which improves the stability of the edge of the head with acceptable strength of the head. The procedure is generally applicable as a design tool for optimal design.

scholarly journals Isolation and Characterization of Lipase Inhibitory Activity from Solanum Tuberosum L (P08-040-19)

2019 ◽  
Vol 3 (Supplement_1) ◽  
Author(s):  
J Inkyu Lim ◽  
Dorsilla Anno Katimbwa
Keyword(s):  
Solanum Tuberosum L ◽  
Water Extract ◽  
Basic Research ◽  
Inhibition Activity ◽  
Funding Sources ◽  
Isolation And Characterization ◽  
Inhibitory Compound ◽  
The Stability ◽  
Basic Research Grant ◽  
Lipase Inhibition

Abstract Objectives The biochemical characteristics of the inhibitory compound to lipase isolated from potato was compared to the commercially available anti-obesity drug, Orlistat. Methods Lipase inhibitory compound was isolated from the water extract from potato by serial solvent extraction and chromatographic purifications. The lipase inhibition kinetics was assessed by double reciprocal Lineweaver-Burk plotting. the potency of lipase inhibition of the compound was compared with Orlistat using 4-MUO as a substrate. Results The lipase inhibitroy compound exhibited mixed type inhibition and high potency with an estimated IC50 of 216 ng/mL in the impure extract. The lipase inhibition activity of the compound is comparable to the commercially available anti-obesity drug, Orlistat, whose IC 50 was 0.4 ng/mL. The compound is stable at low pH (pH 2) and at boiling temperature for 1 h. Storage stability test showed that the compound is stable at least 4 weeks at RT. Conclusions Regarding the stability, solubility in water and lipase inhibition activity, the compound isolated from potato has a potential to be developed as a safe anti-obesity remedy. Funding Sources This study was funded by a basic research grant from Korean National Research Fund.

Stability Analysis of a Supercritical Water Natural Circulation Loop

2012 ◽  
Author(s):  
ZhongChun Li ◽  
JiYang Yu ◽  
XiaoMing Song
Keyword(s):  
Supercritical Water ◽  
Natural Circulation ◽  
Basic Research ◽  
Circulation Loop ◽  
Two Phase ◽  
Water Reactor ◽  
Natural Circulation Loop ◽  
The Stability ◽  
Engineering Physics ◽  
Supercritical Water Reactor

As a part of “supercritical water reactor basic research”, the stability of the natural circulation research plays an important role on the feasibility of supercritical water reactor and experiment research. In this paper, the stability of a supercritical water natural circulation loop built by Department of Engineering Physics, Tsinghua University was studied by numerical method. It was confirmed that the static or Ledinegg instability doesn’t occur in HACA system, and there are no instabilities existing when the inlet enthalpy is larger than critical enthalpy. Instability was observed by numerical way, which is similar to DWOs and PDOs in two phase natural circulation loop. The system parameters’ influence on the instability of supercritical natural circulation loop was studied.

Postural stability in one leg standing on dominant and non-dominant leg in professional soccer players

2017 ◽  
Vol 26 (77) ◽  
pp. 53-64 ◽  
Author(s):  
Przemysław Dębski ◽  
Jacek Mielańczyk ◽  
Rafał Gnat
Keyword(s):  
Postural Stability ◽  
Football Player ◽  
The Body ◽  
Lower Limbs ◽  
Soccer Players ◽  
Balance System ◽  
Professional Soccer ◽  
Sport Competition ◽  
Significant Difference ◽  
The Stability

Stability plays a key role in the sport competition in football. Synchronized operation stabilization of the lower limb and trunk of the support with the dynamic movement of the contralateral limbs allow you to perform tasks specific to the discipline, eg. variety kicking of the ball. Purpose. The aim of the study was to evaluate differences in the capabilities to maintain postural stability in standing on one leg dominant and non-dominant leg with professional players including grouping variables: age, height, weight, volume of training aimed at improving the stability and general internship of football player career. Although commonly assumed that the non-dominant leg is predisposed to act more effective support for the body, the work to date have failed to identify indicated differentiation. It should be noted, however, that they were carried out on small trials in people less active, or among amateur athletes. Basic procedures. The study involved 31 professional soccer players from 1 to 5 level of division. In order to assess postural stability, each of the test performed three times a standard stability test consisting of three 20-second attempt to maintain balance on one leg becoming dominant and non-dominant leg on stabilometric platform BIODEX Balance System. For each of the lower limbs test was repeated three times. Assessment were average angular range deflections platform in the two reference planes, and the volatility of these deflections. These parameters were treated as a measure of postural stability of the respondents. Main findings. In the whole group of patients, no statistically significant differences in the possibilities to maintain postural stability in standing on one leg dominant and non-dominant leg. No significant differences were also detected when considering grouping variables. Conclusions. The results do not indicate a significant difference in the ability to maintain postural stability in standing on one leg dominant and non-dominant leg in professional soccer players.

The Heredity of Biological Time and Population Genetics Diabetes, Lupus Erythematosus, and Peptic Ulcer

1970 ◽  
Vol 19 (4) ◽  
pp. 493-506 ◽  
Author(s):  
L. Gedda ◽  
G. Brenci
Keyword(s):  
Peptic Ulcer ◽  
Lupus Erythematosus ◽  
Individual Variability ◽  
Causal Factors ◽  
Biological Time ◽  
Physical Time ◽  
The Stability ◽  
The Individual ◽  
G Ratio ◽  
Mz Twins

SummaryThe phenomenon of life, in its individual and collective expressions, develops through a sequence of times resulting from the interference of biological with physical time. While physical time is uniform, the biological one differs from one individual to the other, except for MZ twins.The problem of biological time has been studied in physiology and informational genetics from the viewpoint of its succession of single times, although irrespective of the individual variability in their duration. This variability has already been shown by the authors to be hereditary, its inheritance being directly connected with the hereditary unit.Biological time corresponds to the duration of degradation (“chronon”) of the energy of stability (“ergon”) possessed by the gene and, by extension, to the total chronon of the genotypes underlying a given structure or function. Ergon and chronon are correlated index values, thereby constituting a system (“E/C system”).The individual variability of biological time depends on the A-T/G-G ratio in the DNA molecule, on the different amount of genie redundancy and on the different possibilities of repair of corresponding genes. The variability of these or possibly other causal factors determines the stability with respect to the environment in which the information operates, and especially to mutagenic agents.The authors apply the E/C model to epidemiologic data concerning diabetes, lupus erythematosus, and peptic ulcer, and verify the consistency of the experimental data with the theoretical model.

Characteristics of the boundary layer thermal structure at a coastal region of Adélie Land, East Antarctica

1998 ◽  
Vol 10 (1) ◽  
pp. 89-98 ◽  
Author(s):  
B. S. Gera ◽  
S. Argentini ◽  
G. Mastrantonio ◽  
A. Viola ◽  
A. Weill
Keyword(s):  
Boundary Layer ◽  
Thermal Structure ◽  
Coastal Region ◽  
Time Duration ◽  
Thermal Plumes ◽  
Doppler Sodar ◽  
Flow Intensity ◽  
Strong Winds ◽  
The Stability ◽  
Annual Distribution

The boundary layer thermal structure, observed through Doppler sodar, at Dumont d'Urville, has been analysed. Typical echograms of the spiky layers, wavy layers and thermal plumes, except for the eroding inversion, have been observed. The annual distribution of these thermal structures is presented. The spiky layers are observed to coincide with strong winds (mainly katabatic) flowing from the inner continent sector, 90°–180°. The upper boundary of the spiky layers is correlated to the wind direction; the maximum depths (more than 400 m) are confined to 60° wide span centred at 135°. The predominant waves and the spiky layers, tend to occur alternately in accordance with the relative dominance of the katabatic flow intensity and the stability conditions. The sodar signatures of these structures are examined in relation to the onset and dissipation time, duration and the seasonal distribution. Both waves and spiky layers occur at any hour of the day; their maximum occurrence is in winter months. The persistence of the waves varies from a couple of hours to a couple of days while the spiky layers can occur for periods even longer than 3–4 days. The characteristics of these phenomena are associated with the diurnal radiational cycle and the temperature contrast in proximity to the coast.

Parasitoids as biological control agents – a fundamental approach

Parasitology ◽  
1982 ◽  
Vol 84 (4) ◽  
pp. 241-268 ◽  
Author(s):  
J. K. Waage ◽  
M. P. Hassell
Keyword(s):  
Biological Control ◽  
Foraging Behaviour ◽  
Insect Pests ◽  
Basic Research ◽  
Larval Survival ◽  
Biological Control Agents ◽  
Inundative Release ◽  
Control Factors ◽  
The Stability ◽  
Parasitoid Foraging

SUMMARYThis review begins with a description of the parasitoid life-style and the ecological and evolutionary factors which generate the remarkable diversity of insect parasitoids. We then describe the various ways that parasitoids have been used in the biological control of insect pests, and survey their success to date. The use of parasitoids remains largely an art, aided by past experience of success and failure. A more fundamental approach, involving basic research and theory, has not as yet contributed significantly to practical biological control. We explore the potential for such a science of parasitoid use and review basic research on parasitoid ecology and evolution which is of particular relevance to biological control. Mathematical models are used to identify and examine those parasitoid and host attributes which lead to successful biological control. Factors such as parasitoid foraging behaviour, fecundity, larval survival and sex ratio are shown to be important in influencing the depression of host populations and/or the stability of host–parasitoid interactions after depression. Multiple release is discussed and a model for inundative release of parasitoids is explored.

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