Self-interference fluorescence microscopy: three dimensional fluorescence imaging without depth scanning

We present a new method for high-resolution, three-dimensional fluorescence imaging. In contrast to beam-scanning confocal microscopy, where the laser focus must be scanned both laterally and axially to collect a volume, we obtain depth information without the necessity of depth scanning. In this method, the emitted fluorescence is collected in the backward direction and is sent through a phase plate that encodes the depth information into the phase of a spectrally resolved interference pattern. We demonstrate that decoding this phase information allows for depth localization accuracy better than 4 μm over a 500 μm depth-of-field. In a high numerical aperture configuration with a much smaller depth of field, a localization accuracy of tens of nanometers can be achieved. This approach is ideally suited for miniature endoscopes, where space limitations at the endoscope tip render depth scanning difficult. We illustrate the potential for 3D visualization of complex biological samples by constructing a threedimensional volume of the microvasculature of ex vivo murine heart tissue from a single 2D scan. © 2012 Optical Society of America

High speed miniature motorized endoscopic probe for optical frequency domain imaging

We present a miniature motorized endoscopic probe for Optical Coherence Tomography with an outer diameter of 1.65 mm and a rotation speed of 3,000-12,500 rpm. This is the smallest motorized high speed OCT probe to our knowledge. The probe has a motorized distal end which provides a significant advantage over proximally driven probes since it does not require a drive shaft to transfer the rotational torque to the distal end of the probe and functions without a fiber rotary junction. The probe has a focal Full Width at Half Maximum of 9.6 μm and a working distance of 0.47 mm. We analyzed the non uniform rotation distortion and found a location fluctuation of only 1.87° in repeated measurements of the same object. The probe was integrated in a high-speed Optical Frequency Domain Imaging setup at 1310 nm to acquire images from ex vivo pig lung tissue through the working channel of a human bronchoscope. © 2012 Optical Society of America

Evaluation of a standardized test protocol to measure wheelchair-specific anaerobic and aerobic exercise capacity in healthy novices on an instrumented roller ergometer

This study aims to evaluate whether a test protocol with standardized and individualized resistance settings leads to valid wheelchair Wingate tests (WAnT) and graded exercise tests (GXT) in healthy novices. Twenty able-bodied individuals (10M/10F, age 23 ± 2 years, body mass 72 ± 11 kg) performed an isometric strength test, sprint test, WAnT and GXT on a wheelchair ergometer. Using a previously developed set of regression equations, individuals' isometric strength outcome was used to estimate the WAnT result (P30est), from which an effective individual WAnT resistance was derived. The subsequently measured WAnT outcome (P30meas) was used to estimate the GXT outcome (POpeakest) and to scale the individual GXT resistance steps. Estimated and measured outcomes were compared. The WAnT protocol was considered valid when maximal velocity did not exceed 3 m·s-1; the GXT protocol was considered valid when test duration was 8-12 min. P30est did not significantly differ from P30meas, while one participant did not have a valid WanT, as maximal velocity exceeded 3 m·s-1. POpeakest was 10% higher than POpeakmeas, and six participants did not reach a valid GXT: five participants had a test duration under 8 min and one participant over 12 min. The isometric strength test can be used to individually scale the WAnT protocol. The WAnT outcome scaled the protocol for the GXT less accurately, resulting in mostly shorter-than-desired test durations. In conclusion, the evaluated standardized and individualized test protocol was valid for the WAnT but less valid for the GXT among a group of novices. Before implementing the standardized individual test protocol on a broader scale, e.g. among paralympic athletes, it should be evaluated among different athletic wheelchair-dependent populations

Validation of an activity monitor for children who are partly or completely wheelchair-dependent

Background: Children who are wheelchair-dependent are at risk for developing unfavorable physical behavior; therefore, assessment, monitoring and efforts to improve physical behavior should start early in life. VitaMove is an accelerometer-based activity monitor and can be used to detect and distinguish different categories of physical behavior, including activities performed in a wheelchair and activities using the legs. The purpose of this study was to assess the validity of the VitaMove activity monitor to quantify physical behavior in children who are partly or completely wheelchair-dependent. Methods: Twelve children with spina bifida (SB) or cerebral palsy (CP) (mean age, 14 ±4 years) performed a series of wheelchair activities (wheelchair protocol) and, if possible, activities using their legs (n = 5, leg protocol). Activities were performed at their own home or school. In children who were completely wheelchair-dependent, VitaMove monitoring consisted of one accelerometer-based recorder attached to the sternum and one to each wrist. For children who were partly ambulatory, an additional recorder was attached to each thigh. Using video-recordings as a reference, primary the total duration of active behavior, including wheeled activity and leg activity, and secondary agreement, sensitivity and specificity scores were determined. Results: Detection of active behaviour with the VitaMove activity monitor showed absolute percentage errors of 6% for the wheelchair protocol and 10% for the leg protocol. For the wheelchair protocol, the mean agreement was 84%, sensitivity was 80% and specificity was 85%. For the leg protocol, the mean agreement was 83%, sensitivity was 78% and specificity was 90%. Validity scores were lower in severely affected children with CP. Conclusions: The VitaMove activity monitor is a valid device to quantify physical behavior in children who are partly or completely wheelchair-dependent, except for severely affected children and for bicycling

Integrable Hierarchy for Multidimensional Toda Equations and Topological-Anti-topological Fusion

The negative symmetry flows are incorporated into the Riemann-Hilbert problem for the homogeneous $A_m$-hierarchy and its $\hat{gl} (m+1, C)$ extension. A loop group automorphism of order two is used to define a sub-hierarchy of $\hat{gl} (m+1, C)$ hierarchy containing only the odd symmetry flows. The positive and negative flows of the $\pm 1$ grade coincide with equations of the multidimensional Toda model and of topological-anti-topological fusion.Comment: 24+1 pages, some minus signs correcte

Supporting older patients in making healthcare decisions: The effectiveness of decision aids; A systematic review and meta-analysis

Objective: To systematically review randomized controlled trials and clinical controlled trials evaluating the effectiveness of Decision Aids (DAs) compared to usual care or alternative interventions for older patients facing treatment, screening, or care decisions.Methods: A systematic search of several databases was conducted. Eligible studies included patients ≥ 65 years or reported a mean of ≥ 70 years. Primary outcomes were attributes of the choice made and decision making process, user experience and ways in which DAs were tailored to older patients. Meta-analysis was conducted, if possible, or outcomes were synthesized descriptively.Results: Overall, 15 studies were included. Using DAs were effective in increasing knowledge (SMD 0.90; 95% CI [0.48, 1.32]), decreasing decisional conflict (SMD −0.15; 95% CI [−0.29, −0.01]), improving patient-provider communication (RR 1.67; 95% CI [1.21, 2.29]), and preparing patients to make an individualized decision (MD 35.7%; 95% CI [26.8, 44.6]). Nine studies provided details on how the DA was tailored to older patients.Conclusion: This review shows a number of favourable results for the effectiveness of DAs in decision making with older patients.Practice implications: Current DAs can be used to support shared decision making with older patients when faced with treatment, screening or care decisions

Aflibercept in the Treatment of Metastatic Colorectal Cancer

Colorectal cancer is the third most common cancer in the US. In recent decades, an improved understanding of the role of the angiogenesis pathway in colorectal cancer has led to advancements in treatment. Bevacizumab has been shown to improve the progression-free survival and overall survival when combined with cytotoxic chemotherapy in patients with metastatic colorectal cancer, and at present is the only antiangiogenesis agent approved for the treatment of this cancer. Aflibercept is a novel angiogenesis-targeting agent, and has demonstrated efficacy in treating metastatic colorectal cancer in a recent randomized Phase III trial. Here we review the role of angiogenesis in the tumorigenesis of colorectal cancer, strategies for targeting angiogenesis, and the clinical development of aflibercept

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