Combined Atomic Force Microscope and Volumetric Light Sheet System for Correlative Force and Fluorescence Mechanobiology Studies

The central goals of mechanobiology are to understand how cells generate force and how they respond to environmental mechanical stimuli. A full picture of these processes requires high-resolution, volumetric imaging with time-correlated force measurements. Here we present an instrument that combines an open-top, single-objective light sheet fluorescence microscope with an atomic force microscope (AFM), providing simultaneous volumetric imaging with high spatiotemporal resolution and high dynamic range force capability (10 pN – 100 nN). With this system we have captured lysosome trafficking, vimentin nuclear caging, and actin dynamics on the order of one second per single-cell volume. To showcase the unique advantages of combining Line Bessel light sheet imaging with AFM, we measured the forces exerted by a macrophage during FcɣR-mediated phagocytosis while performing both sequential two-color, fixed plane and volumetric imaging of F-actin. This unique instrument allows for a myriad of novel studies investigating the coupling of cellular dynamics and mechanical forces

The integrated Sachs-Wolfe Effect -- Large Scale Structure Correlation

We discuss the correlation between late-time integrated Sachs-Wolfe (ISW) effect in the cosmic microwave background (CMB) temperature anisotropies and the large scale structure of the local universe. This correlation has been proposed and studied in the literature as a probe of the dark energy and its physical properties. We consider a variety of large scale structure tracers suitable for a detection of the ISW effect via a cross-correlation. In addition to luminous sources, we suggest the use of tracers such as dark matter halos or galaxy clusters. A suitable catalog of mass selected halos for this purpose can be constructed with upcoming wide-field lensing and Sunyaev-Zel'dovich (SZ) effect surveys. With multifrequency data, the presence of the ISW-large scale structure correlation can also be investigated through a cross-correlation of the frequency cleaned SZ and CMB maps. While convergence maps constructed from lensing surveys of the large scale structure via galaxy ellipticities are less correlated with the ISW effect, lensing potentials that deflect CMB photons are strongly correlated and allow, probably, the best mechanism to study the ISW-large scale structure correlation with CMB data alone.Comment: 10 Pages, PRD submitte

A comparison of the usage of anal verge and dentate line in measuring distances within the rectum

Introduction: The anal verge is key in determining measurement-based suitability for neoadjuvant radiotherapy in rectal cancer. The dentate line is a distinct anatomic landmark and may permit more accurate measurement for rectal lesions. This study aimed to establish measurative ranges for distances of the rectal valves from the dentate line and the anal verge and to compare variability between the two. Methods: Patients (n = 104) undergoing colonoscopy and sigmoidoscopy were prospectively accrued. The distances of rectal valves were measured from the anal verge and the dentate line respectively by using a vector subtraction-based approach. Distances were correlated with gender, age and body mass index. Standard deviation was the measure of variability. Results: The gross topography of the rectum was remarkably consistent with three valves identifiable in the majority (99 of 104) of patients. The median distance between the dentate line and the anal verge was 2.0 cm. The distances of each rectal valve (proximal to distal) to the anal verge and dentate line were 11.4 ± 2.0 cm, 8.6 ± 2.0 cm, 6.0 ± 1.7 cm and 9.1 ± 1.6 cm, 6.3 ± 1.6 cm, 3.7 ± 1.5 cm, respectively. Betweengroup variability was minimally reduced when using the dentate line as a reference point. Obesity was associated with an increased distance of the proximal rectal valve from the anal verge and the dentate line (p = 0.004 and 0.015 respectively). Conclusions: Rectal valve anatomy is remarkably consistent. Both dentate line and anal verge are reliable landmarks from which distances can be measured within the rectum

Developing Cultural Self-Awareness: The First Step in Values Clarification for Early Interventionists

This article presents a discussion of the need for early interventionists to develop awareness of certain cultural assumptions underlying their practice. A wide range of literature on cultural differences is used to identify five areas of potential dissonance between professionals and families from culturally diverse backgrounds: interpretations of the meaning of disability; concepts of family structure and identity; goals of education; parent-child interaction, and communication style. It is argued that awareness of one's own cultural beliefs in these areas is an essential first step in developing effective collaboration with culturally different families