The mean velocity of two-state models of molecular motor

The motion of molecular motor is essential to the biophysical functioning of living cells. In principle, this motion can be regraded as a multiple chemical states process. In which, the molecular motor can jump between different chemical states, and in each chemical state, the motor moves forward or backward in a corresponding potential. So, mathematically, the motion of molecular motor can be described by several coupled one-dimensional hopping models or by several coupled Fokker-Planck equations. To know the basic properties of molecular motor, in this paper, we will give detailed analysis about the simplest cases: in which there are only two chemical states. Actually, many of the existing models, such as the flashing ratchet model, can be regarded as a two-state model. From the explicit expression of the mean velocity, we find that the mean velocity of molecular motor might be nonzero even if the potential in each state is periodic, which means that there is no energy input to the molecular motor in each of the two states. At the same time, the mean velocity might be zero even if there is energy input to the molecular motor. Generally, the velocity of molecular motor depends not only on the potentials (or corresponding forward and backward transition rates) in the two states, but also on the transition rates between the two chemical states

Implementation of mean-timing and subsequent logic functions on an FPGA

This article describes the implementation of a mean-timer and coincidence logic on a Virtex-5 FPGA for trigger purposes in a particle physics experiment. The novel feature is that the mean-timing and the coincidence logic are not synchronized with a clock which allows for a higher resolution of approximately 400 ps, not limited by a clock frequency.Comment: 15 pages, 11 figure

Crisis-Induced Social Conflicts in the European Union – Trade Union Perspectives: The Emergence of 'Crisis Corporatism' or the Failure of Corporatist Arrangements?

This paper aims to explore the role of labour and trade unions in the repeated shifts of crisis phenomena over the past years. It addresses the question why, confronted with the very profoundness of the crisis, they have failed to develop politically relevant and socially progressive strategies so far. The presented argument not only refers to structural power relations but in particular to the political struggles and processes in which more far-reaching ambitions have been knocked into shape. In that context, the focus is above all on economic stimulus packages, financial market regulation, and current budget consolidation. The paper will be organised as follows: It will start with some general problems of trade unions in generating sufficient power and organisational capacities against the background of the unfolding crisis within the European Union (EU). The next section empirically highlights these developments by discussing the cases of Germany, France, and Spain. The paper then concludes highlighting common challenges and chances, but also the difficulties to form new progressive European alliances

Changes in self-schema structure in cognitive therapy for major depressive disorder: a randomized clinical trial.

Negative cognitive structure (particularly for interpersonal content) has been shown in some research to persist past a current episode of depression and potentially to be a stable marker of vulnerability for depression (D. J. A. Dozois, 2007; D. J. A. Dozois & K. S. Dobson, 2001a). Given that cognitive therapy (CT) is highly effective for treating the acute phase of a depressive episode and that this treatment also reduces the risk of relapse and recurrence, it is possible that CT may alter these stable cognitive structures. In the current study, patients were randomly assigned to CT+ pharmacotherapy (n = 21) or to pharmacotherapy alone (n = 21). Both groups evidenced significant and similar reductions in level of depression (as measured with the Beck Depression Inventory-II and the Hamilton Rating Scale for Depression), as well as automatic thoughts and dysfunctional attitudes. However, group differences were found on cognitive organization in favor of individuals who received the combination of CT+ pharmacotherapy. The implications of these results for understanding mechanisms of change in therapy and the prophylactic nature of CT are discussed

Microtubule depolymerization by the kinesin-8 motor Kip3p: a mathematical model

Proteins from the kinesin-8 family promote microtubule (MT) depolymerization, a process thought to be important for the control of microtubule length in living cells. In addition to this MT shortening activity, kinesin 8s are motors that show plus-end directed motility on MTs. Here we describe a simple model that incorporates directional motion and destabilization of the MT plus end by kinesin 8. Our model quantitatively reproduces the key features of length-vs-time traces for stabilized MTs in the presence of purified kinesin 8, including length-dependent depolymerization. Comparison of model predictions with experiments suggests that kinesin 8 depolymerizes processively, i.e., one motor can remove multiple tubulin dimers from a stabilized MT. Fluctuations in MT length as a function of time are related to depolymerization processivity. We have also determined the parameter regime in which the rate of MT depolymerization is length dependent: length-dependent depolymerization occurs only when MTs are sufficiently short; this crossover is sensitive to the bulk motor concentration.Comment: 34 pages, 11 figure

Changes in Core Beliefs (Early Maladaptive Schemas) and Self-Representation in Cognitive Therapy and Pharmacotherapy for Depression

Randomized clinical trials suggest that cognitive therapy (CT) is comparable to antidepressant medication for the acute treatment of depression. Compelling data also indicate that CT has an added prophylactic benefit relative to pharmacotherapy (PT). The purpose of this study was to examine cognitive change in CT for depression. Participants (N = 42) met diagnostic criteria for a current major depressive episode and were randomly assigned to CT + PT or PT. Participants completed indices of depressive symptomatology, core beliefs (i.e., early maladaptive schemas), and self-attribute redundancy before and after therapy. Self-attribute redundancy was conceptualized as a form of schema organization and operationalized as the number of similar traits that permeate different aspects of self (e.g., as a partner, friend, employee). Treatment change was evident in both groups on self-reported core belief domains, with few between-group differences. Although no group differences were found on attribute redundancy at pre-treatment, there was a significant increase in positive redundancy at post-treatment favoring CT + PT. No group differences were found for negative content. These findings suggest that something about CT may uniquely impact self-representation and that CT may operate by bolstering compensatory schemas

The effects of financialisation and financial development on investment: Evidence from firm-level data in Europe

In this paper we estimate the effects of financialization on physical investment in selected western European countries using panel data based on the balance-sheets of publicly listed non-financial companies (NFCs) supplied by Worldscope for the period 1995-2015. We find robust evidence of an adverse effect of both financial payments (interests and dividends) and financial incomes on investment in fixed assets by the NFCs. This finding is robust for both the pool of all Western European firms and single country estimations. The negative impacts of financial incomes are non-linear with respect to the companies’ size: financial incomes crowd-out investment in large companies, and have a positive effect on the investment of only small, relatively more credit-constrained companies. Moreover, we find that a higher degree of financial development is associated with a stronger negative effect of financial incomes on companies’ investment. This finding challenges the common wisdom on ‘finance-growth nexus’. Our findings support the ‘financialization thesis’ that the increasing orientation of the non-financial sector towards financial activities is ultimately leading to lower physical investment, hence to stagnant or fragile growth, as well as long term stagnation in productivity

Scattering of Noncommutative Waves and Solitons in a Supersymmetric Chiral Model in 2+1 Dimensions

Interactions of noncommutative waves and solitons in 2+1 dimensions can be analyzed exactly for a supersymmetric and integrable U(n) chiral model extending the Ward model. Using the Moyal-deformed dressing method in an antichiral superspace, we construct explicit time-dependent solutions of its noncommutative field equations by iteratively solving linear equations. The approach is illustrated by presenting scattering configurations for two noncommutative U(2) plane waves and for two noncommutative U(2) solitons as well as by producing a noncommutative U(1) two-soliton bound state.Comment: 1+13 pages; v2: reference added, version published in JHE

Modeling the mental health service utilization decisions of university undergraduates: A discrete choice conjoint experiment

Objective: We modeled design factors influencing the intent to use a university mental health service. Participants: Between November 2012 and October 2014, 909 undergraduates participated. Method: Using a discrete choice experiment, participants chose between hypothetical campus mental health services. Results: Latent class analysis identified three segments. A Psychological/Psychiatric Service segment (45.5%) was most likely to contact campus health services delivered by psychologists or psychiatrists. An Alternative Service segment (39.3%) preferred to talk to peer-counselors who had experienced mental health problems. A Hesitant segment (15.2%) reported greater distress but seemed less intent on seeking help. They preferred services delivered by psychologists or psychiatrists. Simulations predicted that, rather than waiting for standard counseling, the Alternative Service segment would prefer immediate access to E-Mental health. The Usual Care and Hesitant segments would wait 6 months for standard counseling. Conclusions: E-Mental Health options could engage students who may not wait for standard services.This project was supported by the Jack Laidlaw Chair in Patient-Centered Health Care and a grant from the Canadian Health Services Research Foundation