An elastomeric grating coupler

We report on a novel nondestructive and reversible method for coupling free space light to planar optical waveguides. In this method, an elastomeric grating is used to produce an effective refractive index modulation on the surface of the optical waveguide. The external elastomeric grating binds to the surface of the waveguide with van der Waals forces and makes conformal contact without any applied pressure. As a demonstration of the feasibility of the approach, we use it to measure the refractive index of a silicon oxynitride film. This technique is nondestructive, reversible, low cost and can easily be applied to the characterization of optical materials for integrated optics

Estimation over Communication Networks: Performance Bounds and Achievability Results

This paper considers the problem of estimation over communication networks. Suppose a sensor is taking measurements of a dynamic process. However the process needs to be estimated at a remote location connected to the sensor through a network of communication links that drop packets stochastically. We provide a framework for computing the optimal performance in the sense of expected error covariance. Using this framework we characterize the dependency of the performance on the topology of the network and the packet dropping process. For independent and memoryless packet dropping processes we find the steady-state error for some classes of networks and obtain lower and upper bounds for the performance of a general network. Finally we find a necessary and sufficient condition for the stability of the estimate error covariance for general networks with spatially correlated and Markov type dropping process. This interesting condition has a max-cut interpretation

Fully automated segmentation and tracking of the intima media thickness in ultrasound video sequences of the common carotid artery

Abstract—The robust identification and measurement of the intima media thickness (IMT) has a high clinical relevance because it represents one of the most precise predictors used in the assessment of potential future cardiovascular events. To facilitate the analysis of arterial wall thickening in serial clinical investigations, in this paper we have developed a novel fully automatic algorithm for the segmentation, measurement, and tracking of the intima media complex (IMC) in B-mode ultrasound video sequences. The proposed algorithm entails a two-stage image analysis process that initially addresses the segmentation of the IMC in the first frame of the ultrasound video sequence using a model-based approach; in the second step, a novel customized tracking procedure is applied to robustly detect the IMC in the subsequent frames. For the video tracking procedure, we introduce a spatially coherent algorithm called adaptive normalized correlation that prevents the tracking process from converging to wrong arterial interfaces. This represents the main contribution of this paper and was developed to deal with inconsistencies in the appearance of the IMC over the cardiac cycle. The quantitative evaluation has been carried out on 40 ultrasound video sequences of the common carotid artery (CCA) by comparing the results returned by the developed algorithm with respect to ground truth data that has been manually annotated by clinical experts. The measured IMTmean ± standard deviation recorded by the proposed algorithm is 0.60 mm ± 0.10, with a mean coefficient of variation (CV) of 2.05%, whereas the corresponding result obtained for the manually annotated ground truth data is 0.60 mm ± 0.11 with a mean CV equal to 5.60%. The numerical results reported in this paper indicate that the proposed algorithm is able to correctly segment and track the IMC in ultrasound CCA video sequences, and we were encouraged by the stability of our technique when applied to data captured under different imaging conditions. Future clinical studies will focus on the evaluation of patients that are affected by advanced cardiovascular conditions such as focal thickening and arterial plaques

Digital Community Voices Committee Initial Agenda

The overarching goal of this committee is to encourage dialogue around diversity education while encouraging a digital media literacy skillset. This committee will serve as a hub for different departments, associations, and individuals representing a wide spectrum of populations within the URI community and will serve to manage the program in a collegial manner. The Digital Community Voices Committee will utilize writing, the production of multimedia content, and educational digital media products (E-books, TV shorts, podcasts, DVDs, and streaming videos) that showcase diversity, inclusion and community of the URI community. The target audience for the program will be the URI community, prospective community members and the global community interested in issues of diversity. The works from this committee have the potential to engage current and future students to become more involved with the URI community and further connect through shared visions and experiences even before they get to URI. Agenda Items 1. Establishing how the committee will function and purpose. 2. Dana is currently sorting through over 1,000 hours of video he has shot to date at URI looking for programming we can immediately air on URI Campus TV and the RI Educational Network. This includes titles we should have available to discuss at our first meeting. 3. Order of titles to be digitized for URI Campus TV and the RI Educational Network (Local Access) 4. Opportunity for training for those on the committee to become Administers of the Community Equity & Diversity Digital Collections (CEDDC). 5. Establishing process and procedure for utilizing the CEDDC and television broadcasting for new and old programing. 6. Volunteers and/or ideas for future projects and programing. 7. People we would like to invite to be members to create stronger partnerships and make the committee sustainable

A review and critique of academic lab safety research

Over the past ten years, there have been several high-profile accidents in academic laboratories around the world, resulting in significant injuries and fatalities. The aftermath of these incidents is often characterized by calls for reflection and re-examination of the academic discipline’s approach to safety research and policy. However, the study of academic lab safety is still underdeveloped and necessary data about changes in safety attitudes and behaviours has not been gathered. This Review article critically examines the state of academic chemical safety research from a multifactorial stance, including research on the occurrence of lab accidents, contributors to lab accidents, the state of safety training research and the cultural barriers to conducting safety research and implementing safer lab practices. The Review concludes by delineating research questions that must be addressed to minimize future serious academic laboratory incidents as well as stressing the need for committed leadership from our research institutions

Attenuated Codon Optimality Contributes to Neural-Specific mRNA Decay in Drosophila.

Tissue-specific mRNA stability is important for cell fate and physiology, but the mechanisms involved are not fully understood. We found that zygotic mRNA stability in Drosophila correlates with codon content: optimal codons are enriched in stable transcripts associated with metabolic functions like translation, while non-optimal codons are enriched in unstable transcripts, including those associated with neural development. Bioinformatic analyses and reporter assays revealed that similar codons stabilize or destabilize mRNAs in the nervous system and other tissues, but the link between codon content and stability is attenuated in the nervous system. We confirmed that optimal codons are decoded by abundant tRNAs while non-optimal codons are decoded by less abundant tRNAs in embryos and in the nervous system. We conclude that codon optimality is a general determinant of zygotic mRNA stability, and attenuation of codon optimality allows trans-acting factors to exert greater influence over mRNA decay in the nervous system

Rancang Bangun Prototipe Knowledge Management System Bahan Ajar Guru dengan Model Seci dan Mvc : Studi Kasus Sdit Al-hikmah Cipayung Depok

The ability of an educational institution in terms of science and technology became one of the very important factors. Despite those two things then it should be accompanied by a qualified human resources and competitive. SDIT Al-Hikmah Cipayung Depok is an Islamic educational institution where the transfer of knowledge is still limited in the forum work meetings there has been no documentation or technology that saves teachers 'knowledge and experience in teaching. Knowledge Management System is the most effective way in tackling the problem and solution sharing and transfer of knowledge teachers at Al-Hikmah SDIT Cipayung Depok. The research method used was the establishment of the SECI model of knowledge, architectural design model application with MVC (Model-View-Controller), testing validation by Focus Group Discussion (FGD) method using a questionnaire, software testing and black box testing and software quality testing with ISO 9126. The result of the research is a Knowledge Management System as the technology transfer of knowledge that is one of the efforts in reducing the use of paper (paperless office), making the efficiency of time, effort and cost, and better documentation management in the SDIT Al-Hikmah Cipayung Depok

Tackling 3D ToF Artifacts Through Learning and the FLAT Dataset

Scene motion, multiple reflections, and sensor noise introduce artifacts in the depth reconstruction performed by time-of-flight cameras. We propose a two-stage, deep-learning approach to address all of these sources of artifacts simultaneously. We also introduce FLAT, a synthetic dataset of 2000 ToF measurements that capture all of these nonidealities, and allows to simulate different camera hardware. Using the Kinect 2 camera as a baseline, we show improved reconstruction errors over state-of-the-art methods, on both simulated and real data.Comment: ECCV 201

Antiresonance and Localization in Quantum Dynamics

The phenomenon of quantum antiresonance (QAR), i.e., exactly periodic recurrences in quantum dynamics, is studied in a large class of nonintegrable systems, the modulated kicked rotors (MKRs). It is shown that asymptotic exponential localization generally occurs for $\eta$ (a scaled $\hbar$) in the infinitesimal vicinity of QAR points $\eta_0$. The localization length $\xi_0$ is determined from the analytical properties of the kicking potential. This ``QAR-localization" is associated in some cases with an integrable limit of the corresponding classical systems. The MKR dynamical problem is mapped into pseudorandom tight-binding models, exhibiting dynamical localization (DL). By considering exactly-solvable cases, numerical evidence is given that QAR-localization is an excellent approximation to DL sufficiently close to QAR. The transition from QAR-localization to DL in a semiclassical regime, as $\eta$ is varied, is studied. It is shown that this transition takes place via a gradual reduction of the influence of the analyticity of the potential on the analyticity of the eigenstates, as the level of chaos is increased.Comment: To appear in Physical Review E. 51 pre-print pages + 9 postscript figure