Search results for "force"
showing 10 items of 3423 documents
Some recent results on the compressive and flexural behaviour of composite members
2005
Experiemntal results from compression and flexural tests on steel tubulare columns having circular or rectangular transverse cross-section and infilled with plain or fiber reinforced concrete (FRC) are analysez. for composite members differenti lengths and different dimensions of transverse cross-section were considered in order to assess the influence on behavior in flexure and in compression.The fiber investigated with different percentage were syntetic, carbon and deformed steel fibers. The constituent materials were characterised through compressive and split tests on conconcrete cylinders. Load.shortning and load-delection curves were determined including the sotnening response. Simpli…
Reliability of measurements during countermovement jump assessments: Analysis of performance across subphases
2020
The aim of this study was to examine the reliability of performance measures in the different phases and sub-phases of the countermovement jump (CMJ). Seventeen male athletes competing at a regional level completed 204 valid trails consisting of the execution of maximal hands-on-waist CMJs performed on a force platform. The vertical ground reaction force (VGRF) data obtained at a sampling frequency of 1000 Hz were used to calculate performance-derived variables and determine key points and jump sub-phases. The relative reliability of 92 variables was assessed using the intraclass correlation coefficient (ICC) from a two-way mixed effects model analyzing the time, force, power, velocity, and…
Acute neuromuscular and endocrine responses and recovery to single session combined endurance and strength loadings: ‘Order effect’ in untrained youn…
2013
The purpose of this study was to investigate acute neuromuscular and endocrine responses and recovery to a single session of combined endurance and strength loading using two loading orders. Forty-two men were demographically matched to perform a single session of combined endurance+strength (E+S) or strength+endurance (S+E) loading. The strength loading was conducted on a leg press and included sets of power, maximal strength and hypertrophic loads with an overall duration of 30 minutes. The endurance loading was conducted on a bike ergometer and performed by continuous cycling over 30min at 65% of subject’s individual maximal Watts. Both loading conditions led to significant acute reducti…
Recognition of briefly presented familiar and unfamiliar faces
2009
Early processing stages in the perception of familiar and unfamiliar faces were studied in four experiments by varying the type of available facial information in a four alternative forced choice recognition task. Both reaction time and recognition accuracy served as dependent measures. The observed data revealed an asymmetry in processing familiar and unfamiliar faces. A markedly weak inversion effect and strong blurring effect suggest a limited usage of spatial relations within early processing stages of unfamiliar faces. Recognition performance for whole familiar faces did not deteriorate due to blurring or the presentation of isolated internal features, suggesting a low level of represe…
Concentric force enhancement during human movement
2001
In order to understand the possible mechanisms contributing to enhanced concentric performance in stretch-shortening cycle exercises in vivo the present study examined knee extension torque, EMG activity and fascicle length of the vastus lateralis muscle in maximal and submaximal human movements. Maximal concentric knee extensions (120 s-1) were done after pre-stretch and pre-isometric conditions by nine volunteers. During shortening at the knee angle of 115 (180 = extended) the knee extension torque was found to be greater in pre-stretch condition (272 vs. 248 Nm, p < 0.05) although the torque level prior to shortening was smaller than in pre-isometric condition (268 vs. 314 Nm, p< 0.05…
La suprema giurisdizione nella Sardegna moderna. Travagli della Real Audiencia (1564-1651)
2019
The institution of the Real Audiencia in the kingdom of Sardinia since the 1560s is part of a wider process which saw the rise and development of royal supreme courts of justice in several European countries of the early modern period. In fact, major State formation processes all around Europe required that monarchs increased their control on local authorities and that new increasingly centralised systems of judicial review gained precedence over all particular jurisdictions, feudal as well as municipal. This brought about a dramatic transformation in the field of criminal law enforcement and administration of justice.
Influence of organic material and sample parameters on the surface potential in Kelvin probe measurements
2019
Financial support provided by ERDF 1.1.1.1 activity project Nr. 1.1.1.1/16/A/046 “Application assessment of novel organic materials by prototyping of photonic devices” as well as Scientific Research Project for Students and Young Researchers Nr. SJZ2016/20 realized at the Institute of Solid State Physics, University of Latvia is greatly acknowledged.
Disguised Employment - The Nature of Forced Entrepreneurship
2007
Present labor markets are in the wind of change. A widely made distinction between employees and individual contractors has been challenged. The study discusses abductively, i.e. both conceptually and empirically, the nature of being a responsible employer. Consequently, the two central concepts are: a) responsibility and b) employment relationship. The empirical research task is: Why does disguised employment exist? Question of the research is: What is disguised employment as forced entrepreneurship? The approach is qualitative and abductive, which in this case means a two-way dialogue between the findings gained from literature and interviews. For this exploration, twelve open and unstruc…
Synthesis, structure and photophysical properties of a highly luminescent terpyridine-diphenylacetylene hybrid fluorophore and its metal complexes
2014
A new fluorescent terpyridyl-diphenylacetylene hybrid fluorophore 4'-[4-{(4-methoxyphenyl)ethynyl}phenyl]-2,2':6',2''-terpyridine, L, was synthesized via Sonogashira cross-coupling of 4'-(4-bromophenyl)-2,2':6',2''-terpyridine and 4-ethynylanisole in the presence of Pd(PPh3)4/CuI as a catalyst. The solid state structure of L shows a trans arrangement of pyridine nitrogen atoms along the interannular bond in the terpyridine domain. Five transition metal complexes of L, {[FeL2](CF3SO3)2 (1), [ZnL2](ClO4)2 (2), [CdL2](ClO4)2 (3), [RuL2](PF6)2 (4), and PtMe3IL (5)}, have also been synthesized and characterized by spectroscopic methods and single crystal X-ray analysis. The X-ray crystal structu…
Orientation and molecular contacts of melatonin confined into AOT and lecithin reversed micellar systems
2008
Abstract The state of increasing amounts of melatonin (MLT) confined in dry AOT or lecithin reversed micelles dispersed in CCl 4 has been investigated by UV–vis and 1 H NMR spectroscopies. The experimental results are consistent with MLT totally entrapped in reversed micelles, as a consequence of specific melatonin/surfactant interaction; the main driving force of the MLT solubilization in the core of reversed micelles is the establishment of H-bonding between the MLT NH groups (both indolic and amidic) and the head group of surfactants. The short contacts deduced from intermolecular NOEs are accounted for by favourable interactions between the surfactant's polar head and the H7–NH–H2 fragm…