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We investigate the use of self-tracking data and unsupervised mixed-membership models to phenotype endometriosis. Endometriosis is a systemic, chronic condition of women in reproductive age and, at the same time, a highly enigmatic condition with no known biomarkers to monitor its progression and no established staging. We leverage data collected through a self-tracking app in an observational research study of over 2,800 women with endometriosis tracking their condition over a year and a half (456,900 observations overall). We extend a classical mixed-membership model to accommodate the idiosyncrasies of the data at hand (i.e., the multimodality of the tracked variables). Our experiments show that our approach identifies potential subtypes that are robust in terms of biases of self-tracked data (e.g., wide variations in tracking frequency amongst participants), as well as to variations in hyperparameters of the model. Jointly modeling a wide range of observations about participants (symptoms, quality of life, treatments) yields clinically meaningful subtypes that both validate what is already known about endometriosis and suggest new findings., Comment: As presented in Machine Learning for Healthcare 2018, https://www.mlforhc.org/2018-conference/

The DEPFET collaboration develops highly granular, ultra-transparent active pixel detectors for high-performance vertex reconstruction at future collider experiments. The characterization of detector prototypes has proven that the key principle, the integration of a first amplification stage in a detector-grade sensor material, can provide a comfortable signal to noise ratio of over 40 for a sensor thickness of 50-75 $\mathrm{\mathbf{\mu m}}$. ASICs have been designed and produced to operate a DEPFET pixel detector with the required read-out speed. A complete detector concept is being developed, including solutions for mechanical support, cooling and services. In this paper the status of DEPFET R & D project is reviewed in the light of the requirements of the vertex detector at a future linear $\mathbf{e^+ e^-}$ collider., Comment: 10 pages

We consider planning problems on a punctured Euclidean spaces, $\mathbb{R}^D - \widetilde{\mathcal{O}}$, where $\widetilde{\mathcal{O}}$ is a collection of obstacles. Such spaces are of frequent occurrence as configuration spaces of robots, where $\widetilde{\mathcal{O}}$ represent either physical obstacles that the robots need to avoid (e.g., walls, other robots, etc.) or illegal states (e.g., all legs off-the-ground). As state-planning is translated to path-planning on a configuration space, we collate equivalent plannings via topologically-equivalent paths. This prompts finding or exploring the different homology classes in such environments and finding representative optimal trajectories in each such class. In this paper we start by considering the problem of finding a complete set of easily computable homology class invariants for $(N-1)$-cycles in $(\mathbb{R}^D - \widetilde{\mathcal{O}})$. We achieve this by finding explicit generators of the $(N-1)^{st}$ de Rham cohomology group of this punctured Euclidean space, and using their integrals to define cocycles. The action of those dual cocycles on $(N-1)$-cycles gives the desired complete set of invariants. We illustrate the computation through examples. We further show that, due to the integral approach, this complete set of invariants is well-suited for efficient search-based planning of optimal robot trajectories with topological constraints. Finally we extend this approach to computation of invariants in spaces derived from $(\mathbb{R}^D - \widetilde{\mathcal{O}})$ by collapsing subspace, thereby permitting application to a wider class of non-Euclidean ambient spaces., Comment: 28 pages

We approach the problem of the computation of persistent homology for large datasets by a divide-and-conquer strategy. Dividing the total space into separate but overlapping components, we are able to limit the total memory residency for any part of the computation, while not degrading the overall complexity much. Locally computed persistence information is then merged from the components and their intersections using a spectral sequence generalizing the Mayer-Vietoris long exact sequence. We describe the Mayer-Vietoris spectral sequence and give details on how to compute with it. This allows us to merge local homological data into the global persistent homology. Furthermore, we detail how the classical topology constructions inherent in the spectral sequence adapt to a persistence perspective, as well as describe the techniques from computational commutative algebra necessary for this extension. The resulting computational scheme suggests a parallelization scheme, and we discuss the communication steps involved in this scheme. Furthermore, the computational scheme can also serve as a guideline for which parts of the boundary matrix manipulation need to co-exist in primary memory at any given time allowing for stratified memory access in single-core computation. The spectral sequence viewpoint also provides easy proofs of a homology nerve lemma as well as a persistent homology nerve lemma. In addition, the algebraic tools we develop to approch persistent homology provide a purely algebraic formulation of kernel, image and cokernel persistence (D. Cohen-Steiner, H. Edelsbrunner, J. Harer, and D. Morozov. Persistent homology for kernels, images, and cokernels. In Proceedings of the twentieth Annual ACM-SIAM Symposium on Discrete Algorithms, pages 1011-1020. Society for Industrial and Applied Mathematics, 2009.), Comment: 15 pages, 10 figures, submitted to the ACM Symposium on Computational Geometry

Many processes must complete in the presence of failures. Different systems respond to task failure in different ways. The system may resume a failed task from the failure point (or a saved checkpoint shortly before the failure point), it may give up on the task and select a replacement task from the ready queue, or it may restart the task. The behavior of systems under the first two scenarios is well documented, but the third ({\em RESTART}) has resisted detailed analysis. In this paper we derive tight asymptotic relations between the distribution of {\em task times} without failures to the {\em total time} when including failures, for any failure distribution. In particular, we show that if the task time distribution has an unbounded support then the total time distribution $H$ is always heavy-tailed. Asymptotic expressions are given for the tail of $H$ in various scenarios. The key ingredients of the analysis are the Cram\'er--Lundberg asymptotics for geometric sums and integral asymptotics, that in some cases are obtained via Tauberian theorems and in some cases by bare-hand calculations.

The Information Acquisition Preference Inventory was used to examine cognitive styles in relationship to students' use of study tasks and to assess subjects' preferred ways of learning and problem solving. The inventory, which has students rank words describing their own learning behavior, identifies four distinctive learning preference modes: concrete sequential (CS), concrete random (CR), abstract sequential (AS), and abstract random (AR). A study skills survey completed by 40 students enrolled in a college reading and study skills course indicated that the concrete sequential learner was predominant among the students sampled. Not only were 46% of the students exhibiting one learning preference (concrete sequential learners), but 79% of the double dominant learners had a CS mixture. As for study techniques, the greatest number of learners in all categories reported using personal schedules "sometimes," with the next largest number using schedules "almost always." Most students reported using the textbook study system "sometimes," and the Cornell note-taking method and mapping techniques "very little" or "never." Results also indicated that the concrete random learners used the study techniques somewhat more than did the other students. (Appendixes include the study skills survey and the Information Acquisition Preference Inventory.) (HOD)

This paper considers what can be done to shape an educational system that meets the needs of all students; it then recommends such a system to replace the existing situation in which certain students are labeled as "handicapped" and placed in separate programs. In evaluating the current situation, the paper examines existing educational practices for students with handicaps, focusing on provisions and implementation of Public Law 94-142, funding, referral and assessment, student placement in the least restrictive environment, and program outcomes. Intermediate strategies are presented for bridging the gap between special and general education to create a unified system. These strategies include, among others, strengthening the holding power of general education and making funds available to meet student needs, regardless of categorical labels or location of services provided. A vision of the future calls for such reforms as: viewing handicap as a social construct, recognizing various types of intelligences, framing the student's "problem" as a mismatch between learning needs and the instructional system, involving parents as partners, focusing on student achievement as the critical outcome, and improving educational productivity. Changes that can be accomplished within the present legislative situation are outlined. (JDD)

This study was performed to assess the effect of field independence/dependence on the successful use of mapping or outlining to take notes from textbooks. Success was measured in terms of student performance on a comprehension test and thoroughness of notetaking. The study sample of 38 students enrolled in reading and study skills courses at a community college in Western Pennsylvania was divided into three groups: a group who received training in mapping/networking, a group who received training in outlining/paraphrasing, and a control group that received no training in notetaking. In the first class session, students were taught either the mapping or outlining procedure and were told to take notes on a passage for homework. Two days later, students evaluated and discussed their homework assignment in small groups. A week later, students were given the Group Embedded Figures Test (GEFT) to assess relative field independence/dependence and were tested on the text material. In the final stage of the process, two raters assessed the thoroughness of the students' notes. Study findings included the following: (1) there were no statistically significant differences between the experimental groups in terms of mean scores on the comprehension test or thoroughness of notes; (2) field-independent students had higher mean test scores using the mapping technique, while field-dependent students had higher scores using outlining; and (3) while there was a significant positive correlation between the GEFT scores of students in the mapping group and their comprehension test scores, there was no similar correlation for students in the outlining group. Based on study findings, teachers were urged to guide students into the notetaking technique best suited to them. (JMC)

Expanding on a 1987 article, the authors argue that inclusion provides all students with education that is both individual and integrated. They stress that the inclusionary model should be part of the school restructuring debate and that special education should be viewed as a matter of social justice and equity. (SK)

This publication contains critical analyses of filmstrips dealing with five major world areas: Russia and East Europe, Latin America, Africa, Asia, and the Near East. The filmstrips are for use in elementary and secondary classrooms. One hundred and fifty filmstrips produced between 1970 and the present and available from commercial publishers and distributors were chosen for inclusion. Each filmstrip was reviewed by at least two persons, one with expertise in the content area and one with expertise in curriculum and instruction. The evaluations are organized by area under study and by grade level within each area. Bibliographical data provided for each entry includes title of filmstrip, publisher, publication date, grade level, and filmstrip components. The evaluation contains a description of the filmstrip's subject matter and major themes, a critical evaluation of the strengths and weaknesses of the filmstrip, and a discussion of the Teacher's Guide. The evaluation instrument utilized is included. This publication is the second stage of the Multicultural Education Project of the UCLA Curriculum Inquiry Center which was established to further multicultural studies in the K-12 area. In the first stage of the project, center staff developed annotated bibliographies of print and nonprint learning materials dealing with the five major world areas. (Author/RM)

The implementation of a 10-day Israeli-designed comprehensive pre-elementary education training course for untrained teachers in Singapore is described in this report. The course was designed (1) to provide untrained teachers with experience in setting up an educational environment, (2) to provide trained teachers with the opportunity to share skills, ideas, and materials, and to create a pedagogical center, and (3) to offer trained teachers the opportunity to train the untrained teachers. In addition to a general overview of early childhood education, topics discussed in the workshops include children's learning processes, the teacher's role, the curriculum and curriculum development, content and teaching techniques, creative expression, organizing the physical environment, managing group processes, and working with parents and the community. The orientation period experienced by the Israeli trainers is described, the day by day course schedule is presented, and other descriptive materials related to the implementation and evaluation of the training workshops are provided. A list of participants and a course evaluation form are appended. (Author/RH)

Apollo 11 lunar samples organic compounds analysis by mass spectroscopy, gas and liquid chromatography and nuclear magnetic resonance

Operating parameters and separation of nucleotides on pellicular ion exchangers investigated by liquid chromatographic system

Multichannel photoionization of atomic systems obtained with dipole approximation assuming LS COUPLING, using wave functions

Complex organic compounds analysis by fast- electrical-scanning high resolution mass spectrometry and gas chromatography

System, incorporating Teflon membrane, to selectively remove carrier gas from column effluent prior to entry into mass spectrometer

High resolution mass spectra obtained from fast magnetic scans of gas chromatographic effluents

Fast scan high resolution mass spectrometer system for use with gas chromatography instrumentation

Relative rate constants for energy transfer from excited argon atoms to various organic molecules

Energy transfer between molecules and excited atoms - quenching of excited argon atoms formed by beta radiation from tritium source and low energy electron impact

Xenon and krypton as carrier gases in a highly sensitive ionization system, for detection of permanent gases and organic vapors, by gas chromatography

Argon metastable atoms in ionization of organic molecules

Xenon and krypton as carrier gases for highly sensitive detection system for gas chromatography