Force-extension curves (FECs), which quantify the response of a variety of biomolecules subject to mechanical force (f), are often quantitatively fit using worm-like chain (WLC) or freely jointed chain (FJC) models. These models predict that the chain extension, x, normalized by the contour length increases linearly at small f and at high forces scale as x ~ (1 - f(-α)), where α = 0.5 for WLC a...

The wormlike-chain (WLC) model is widely used to describe the energetics of DNA bending. Motivated by recent experiments, alternative, so-called subelastic chain models were proposed that predict a lower elastic energy of highly bent DNA conformations. Until now, no unambiguous verification of these models has been obtained because probing the elasticity of DNA on short length scales remains ch...

Employed workers often have family responsibilities such as childcare or homemaking. This dual burden may increase work-related health problems, particularly if there are conflicts between work and family responsibilities. This study assessed whether difficulty in work-life balance is associated with musculoskeletal disorders (MSD) among Korean employees. Data from the population-based Korean W...

Compared the effects of 2 psychotherapies based on divergent conceptualizations of depression in later life. Seventy-five older adults diagnosed with major depressive disorder were assigned randomly to problem-solving therapy (PST), reminiscence therapy (RT), or a waiting-list control (WLC) condition. Participants in PST and RT were provided with 12 weekly sessions of group treatment. Dependent...

Based on experiments with the locust olfactory system, we demonstrate that model sensory neural networks with lateral inhibition can generate stimulus specific identity-temporal patterns in the form of stimulus-dependent switching among small and dynamically changing neural ensembles (each ensemble being a group of synchronized projection neurons). Networks produce this switching mode of dynami...

The movement of many animals may follow Lévy patterns. The underlying generating neuronal dynamics of such a behavior is unknown. In this paper we show that a novel discovery of multifractality in winnerless competition (WLC) systems reveals a potential encoding mechanism that is translatable into two dimensional superdiffusive Lévy movements. The validity of our approach is tested on a conduct...

We present a powerful experimental tool and analysis for characterization of two-photon absorption (2PA) spectra. We demonstrate this method with ZnS and then apply it to organic dyes in solution. We also compare the results with those from other methods such as two-photon fluorescence spectroscopy. This femtosecond pump-probe method uses a white-light continuum (WLC) as the probe to produce a ...

We study the possibility of realizing white light cavities (WLCs)—cavities which essentially resonate over a continuous band and not at discrete frequencies, by utilizing linearly chirped Bragg reflectors (LCBGs) for phase compensation. Analytical and numerical analyses show that this goal cannot be achieved because the reflection of a specific frequency by a LCBG cannot be modeled as occurring...

We present an experimental technique along with the method of data analysis to give nondegenerate two-photon absorption (2PA) spectra. We use a femtosecond pump pulse and a white-light continuum (WLC) probe to rapidly generate the 2PA spectra of a variety of materials. In order to analyze data taken with this method, the spectral and temporal characteristics of the WLC must be known, along with...