Individual differences in intrinsic ankle stiffness and their relationship to body sway and ankle torque

When standing, intrinsic ankle stiffness is smaller when measured using large perturbations, when sway size is large, and when background torque is low. However, there is a large variation in individual intrinsic ankle stiffness. Here we determine if individual variation has consequences for postural control. We examined the relationship between ankle stiffness, ankle torque and body sway across different individuals. Ankle stiffness was estimated in 19 standing participants by measuring torque responses to small, brief perturbations. Perturbation sizes of 0.2 & 0.9 degrees (both lasting 140 ms) measured short- and long-range stiffness respectively, while participants either stood quietly on a fixed platform or were imperceptibly tilted to reduce stability (0.1 Hz sinusoid; 0.2 & 0.4 deg). The spontaneous body sway component (natural random relatively rapid postural adjustments) and background ankle torque were averaged from sections immediately before perturbations. The results show that, first, intrinsic ankle stiffness is positively associated with ankle torque, and that this relationship is stronger for long-range stiffness. Second, intrinsic ankle stiffness is negatively associated with body sway, but, in contrast to the relationship with torque, this relationship is stronger for short-range stiffness. We conclude that high short-range intrinsic ankle stiffness is associated with reduced spontaneous sway, although the causal relationship between these two parameters is unknown. These results suggest that, in normal quiet standing where sway is very small, the most important determinant of intrinsic ankle stiffness may be stillness. In less stable conditions, intrinsic ankle stiffness may be more dependent on ankle torque.

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DETRENDED FLUCTUATION ANALYSIS OF AUTOREGRESSIVE PROCESSES

Fluctuation and Noise Letters ◽

10.1142/s0219477507003908 ◽

2007 ◽

Vol 07 (03) ◽

pp. L249-L255 ◽

Cited By ~ 10

Author(s):

VASILE V. MORARIU ◽

LUIZA BUIMAGA-IARINCA ◽

CĂLIN VAMOŞ ◽

ŞTEFAN M. ŞOLTUZ

Keyword(s):

Long Range ◽

Detrended Fluctuation Analysis ◽

Short Range ◽

Interaction Constant ◽

Fluctuation Analysis ◽

Autoregressive Processes ◽

Long Range Correlations ◽

Correlation Exponent ◽

The Relationship ◽

Detrended Fluctuation

Autoregressive processes (AR) have typical short-range memory. Detrended Fluctuation Analysis (DFA) was basically designed to reveal long-range correlations in non stationary processes. However DFA can also be regarded as a suitable method to investigate both long-range and short-range correlations in non stationary and stationary systems. Applying DFA to AR processes can help understanding the non-uniform correlation structure of such processes. We systematically investigated a first order autoregressive model AR(1) by DFA and established the relationship between the interaction constant of AR(1) and the DFA correlation exponent. The higher the interaction constant the higher is the short-range correlation exponent. They are exponentially related. The investigation was extended to AR(2) processes. The presence of an interaction between distant terms with characteristic time constant in the series, in addition to a near by interaction will increase the correlation exponent and the range of correlation while the effect of a distant negative interaction will significantly decrease the range of interaction, only. This analysis demonstrate the possibility to identify an AR(1) model in an unknown DFA plot or to distinguish between AR(1) and AR(2) models.

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The Liberal, The Conservative, and the Pope

Worldview ◽

10.1017/s0084255900006367 ◽

1964 ◽

Vol 7 (11) ◽

pp. 13-15

Author(s):

Michael Novak

Keyword(s):

Civil Rights ◽

Long Range ◽

Short Range ◽

Present Position ◽

Moral Competence ◽

Moral Principles ◽

Political Statement ◽

Uncertain Future ◽

The Relationship

Both Catholics and non-Catholics attempt to enlist the Pope as a partisan of one or another political cause: disarmament, socialization, civil rights, aid for underdeveloped nations, the condemnation of a Hitler. The relationship between morality and politics, however, is ambiguous. Good men may well disagree about which long-range or short-range political programs are best calculated to serve man's moral interests. What, then, is the present position of the Catholic—liberal or conservative—when the Pope makes a moral-political statement about the issues of our time?In its general lines, the traditional answer to this question is simple enough. There are three elements to distinguish: (1) moral principles; (2) political programs; (3) concrete decisions. The Pope's moral competence extends most clearly to declarations about principles. In proportion as judgments about historical facts, present trends, and the yet uncertain future are involved in political programs, the Pope's competence becomes increasingly ambiguous; his is increasingly but one of many prophetic voices “crying in the wilderness.”

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A model for anteroposterior patterning of the vertebrate limb based on sequential long- and short-range Shh signalling and Bmp signalling

Development ◽

10.1242/dev.127.7.1337 ◽

2000 ◽

Vol 127 (7) ◽

pp. 1337-1348 ◽

Cited By ~ 6

Author(s):

G. Drossopoulou ◽

K.E. Lewis ◽

J.J. Sanz-Ezquerro ◽

N. Nikbakht ◽

A.P. McMahon ◽

...

Keyword(s):

Long Range ◽

Short Range ◽

Limb Bud ◽

Anteroposterior Patterning ◽

Dose Dependent Fashion ◽

Bmp Signalling ◽

High Level ◽

The Relationship ◽

Dose Dependent ◽

Digit Identity

It has been proposed that digit identity in chick limb bud is specified in a dose-dependent fashion by a long-range morphogen, produced by the polarising region. One candidate is Sonic hedgehog (Shh) protein, but it is not clear whether Shh acts long or short range or via Bmps. Here we dissect the relationship between Shh and Bmp signalling. We show that Shh is necessary not only for initiating bmp2 expression but also for sustaining its expression during the period when additional digits are being specified. We also show that we can reproduce much of the effect of Shh during this period by applying only Bmp2. We further demonstrate that it is Bmps that are responsible for digit specification by transiently adding Noggin or Bmp antibodies to limbs treated with Shh. In such limbs, multiple additional digits still form but they all have the same identity. We also explored time dependency and range of Shh signalling by examining ptc expression. We show that high-level ptc expression is induced rapidly when either Shh beads or polarising regions are grafted to a host limb. Furthermore, we find that high-level ptc expression is first widespread but later more restricted. All these data lead us to propose a new model for digit patterning. We suggest that Shh initially acts long range to prime the region of the limb competent to form digits and thus control digit number. Then later, Shh acts short range to induce expression of Bmps, whose morphogenetic action specifies digit identity.

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Introduction to methods of describing the forecast on the risk of failure to the means of transport

Research Works of Air Force Institute of Technology ◽

10.2478/v10041-012-0008-y ◽

2012 ◽

Vol 30 (1) ◽

pp. 119-127

Author(s):

Henryk Tomaszek ◽

Ryszard Kaleta ◽

Mariusz Zieja

Keyword(s):

Long Range ◽

Failure Rate ◽

Risk Of Failure ◽

The Relationship ◽

Preliminary Description

The paper is an attempt to describe the forecast on the risk of damages resulting from failures to the means of transport. It has been assumed that the product of the probability of failure (fault) occurrence and measures of effects thereof are to be used to estimate the risk. The below presented dependences that describe the risk of damages have been based on the failure rate. With the available literature as the basis, a preliminary description of the probability of a failure (fault) and the level of losses has been proposed. The paper gives dependences on short- and long-range risk forecasts. To determine the relationship for the probability of a failure (fault), the failure rate has been used.

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Structural basis of long-range to short-range synaptic transition in NHEJ

Nature ◽

10.1038/s41586-021-03458-7 ◽

2021 ◽

Author(s):

Siyu Chen ◽

Linda Lee ◽

Tasmin Naila ◽

Susan Fishbain ◽

Annie Wang ◽

...

Keyword(s):

Long Range ◽

Short Range ◽

Structural Basis

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Exergy analysis of a turboprop engine at different flight altitude and speeds using novel consideration

International Journal of Turbo and Jet Engines ◽

10.1515/tjj-2020-0017 ◽

2020 ◽

Vol 0 (0) ◽

Author(s):

Ali Dinc ◽

Yousef Gharbia

Keyword(s):

Fuel Consumption ◽

Thermal Efficiency ◽

Exergy Efficiency ◽

Specific Fuel Consumption ◽

Flight Altitude ◽

Fuel Flow ◽

Turboprop Engine ◽

Shaft Power ◽

Two Parameters ◽

The Relationship

Abstract In this study, exergy efficiency calculations of a turboprop engine were performed together with main performance parameters such as shaft power, specific fuel consumption, fuel flow, thermal efficiency etc., for a range of flight altitude (0–14 km) and flight speeds (0–0.6 Mach). A novel exergy efficiency formula was derived in terms of specific fuel consumption and it is shown that these two parameters are inversely proportional to each other. Moreover, a novel exergy efficiency and thermal efficiency relation was also derived. The relationship showed that these two parameters are linearly proportional to each other. Exergy efficiency of the turboprop engine was found to be in the range of 23–33%. Thermal efficiency of the turboprop engine was found to be around 25–35%. Exergy efficiency is higher at higher speeds and altitude where the specific fuel consumption is lower. Conversely, exergy efficiency of the engine is lower for lower speeds and altitude where the specific fuel consumption is higher.

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Comparison of short-range order in irradiated dysprosium titanates

npj Materials Degradation ◽

10.1038/s41529-021-00165-6 ◽

2021 ◽

Vol 5 (1) ◽

Author(s):

Roman Sherrod ◽

Eric C. O’Quinn ◽

Igor M. Gussev ◽

Cale Overstreet ◽

Joerg Neuefeind ◽

...

Keyword(s):

Long Range ◽

Short Range ◽

Structural Model ◽

Ion Irradiation ◽

Function Analysis ◽

Ion Beam ◽

Structural Response ◽

Heavy Ion ◽

Range Order ◽

Radiation Resistant

AbstractThe structural response of Dy2TiO5 oxide under swift heavy ion irradiation (2.2 GeV Au ions) was studied over a range of structural length scales utilizing neutron total scattering experiments. Refinement of diffraction data confirms that the long-range orthorhombic structure is susceptible to ion beam-induced amorphization with limited crystalline fraction remaining after irradiation to 8 × 1012 ions/cm2. In contrast, the local atomic arrangement, examined through pair distribution function analysis, shows only subtle changes after irradiation and is still described best by the original orthorhombic structural model. A comparison to Dy2Ti2O7 pyrochlore oxide under the same irradiation conditions reveals a different behavior: while the dysprosium titanate pyrochlore is more radiation resistant over the long-range with smaller degree of amorphization as compared to Dy2TiO5, the former involves more local atomic rearrangements, best described by a pyrochlore-to-weberite-type transformation. These results highlight the importance of short-range and medium-range order analysis for a comprehensive description of radiation behavior.

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Pervasive cooperative mutational effects on multiple catalytic enzyme traits emerge via long-range conformational dynamics

Nature Communications ◽

10.1038/s41467-021-21833-w ◽

2021 ◽

Vol 12 (1) ◽

Author(s):

Carlos G. Acevedo-Rocha ◽

Aitao Li ◽

Lorenzo D’Amore ◽

Sabrina Hoebenreich ◽

Joaquin Sanchis ◽

...

Keyword(s):

Long Range ◽

Fitness Landscape ◽

Conformational Dynamics ◽

P450 Monooxygenase ◽

Access Channel ◽

Long Range Interactions ◽

Limited Protein ◽

Dynamics Simulations ◽

The Relationship ◽

Single Enzyme

AbstractMultidimensional fitness landscapes provide insights into the molecular basis of laboratory and natural evolution. To date, such efforts usually focus on limited protein families and a single enzyme trait, with little concern about the relationship between protein epistasis and conformational dynamics. Here, we report a multiparametric fitness landscape for a cytochrome P450 monooxygenase that was engineered for the regio- and stereoselective hydroxylation of a steroid. We develop a computational program to automatically quantify non-additive effects among all possible mutational pathways, finding pervasive cooperative signs and magnitude epistasis on multiple catalytic traits. By using quantum mechanics and molecular dynamics simulations, we show that these effects are modulated by long-range interactions in loops, helices and β-strands that gate the substrate access channel allowing for optimal catalysis. Our work highlights the importance of conformational dynamics on epistasis in an enzyme involved in secondary metabolism and offers insights for engineering P450s.

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