Smoothing the Transition to Mandatory Electronic Theses

After a year of voluntary submissions, Caltech is requiring electronic thesis submission for all graduate students effective July 1, 2002. Website development, user education, collaboration between library and campus computing staff, and with faculty and the dean's office are all integral to the transition

Reports and Maps of the Geological Survey Released Only in the Open Files, 1966

There is a reference to the Espey "Some effects on urbanization on storm runoff, Waller Creek".Waller Creek Working Grou

Taking the Plunge: Requiring the ETD

It made sense for Caltech, the California Institute of Technology (a private, technically focused, U.S. university, http://www.caltech.edu), to go electronic when it comes to theses. It took, however, more than three years: From March 1999 when Prof. Ed Fox of the Virginia Technical University spoke at Caltech to July 2002 when ETDs became required for all PhD candidates. How was it done and what are the lessons learned

Capacity Constrained Routing Algorithms for Evacuation Route Planning

Efficient tools are needed to identify routes and schedules to evacuate affected populations to safety in face of natural disasters or terrorist attacks. Challenges arise due to violation of key assumptions (e.g. stationary ranking of alternative routes, Wardrop equilibrium) behind popular shortest path algorithms (e.g. Dijktra\u27s, A*) and microscopic traffic simulators (e.g. DYNASMART). Time-expanded graphs (TEG) based mathematical programming paradigm does not scale up to large urban scenarios due to excessive duplication of transportation network across time-points. We present a new approach, namely Capacity Constrained Route Planner (CCRP), advancing ideas such as Time-Aggregated Graph (TAG) and an ATST function to provide earliest-Arrival-Time given any Start-Time. Laboratory experiments and field use in Twincities for DHS scenarios (e.g. Nuclear power plant, terrorism) show that CCRP is much faster than the state of the art. A key Transportation Science insight suggests that walking the first mile, when appropriate, may speed-up evacuation by a factor of 2 to 3 for many scenarios. Geographic Information Science (e.g. Time Geography) contributions include a novel representation (e.g. TAG) for spatio-temporal networks. Computer Science contributions include graph theory limitations (e.g. non-stationary ranking of routes, non-FIFO behavior) and scalable algorithms for traditional routing problems in time-varying networks, as well as new problems such as identifying the best start-time (for a given arrival-time deadline) to minimize travel-time

Bear Facts

https://openspace.dmacc.edu/banner_news/1465/thumbnail.jp

Bear Facts

https://openspace.dmacc.edu/banner_news/1465/thumbnail.jp

Quasi-experimental study designs series-paper 6: risk of bias assessment.

OBJECTIVES: Rigorous and transparent bias assessment is a core component of high-quality systematic reviews. We assess modifications to existing risk of bias approaches to incorporate rigorous quasi-experimental approaches with selection on unobservables. These are nonrandomized studies using design-based approaches to control for unobservable sources of confounding such as difference studies, instrumental variables, interrupted time series, natural experiments, and regression-discontinuity designs. STUDY DESIGN AND SETTING: We review existing risk of bias tools. Drawing on these tools, we present domains of bias and suggest directions for evaluation questions. RESULTS: The review suggests that existing risk of bias tools provide, to different degrees, incomplete transparent criteria to assess the validity of these designs. The paper then presents an approach to evaluating the internal validity of quasi-experiments with selection on unobservables. CONCLUSION: We conclude that tools for nonrandomized studies of interventions need to be further developed to incorporate evaluation questions for quasi-experiments with selection on unobservables

Differences in Gut Microbiome in Hospitalized Immunocompetent vs. Immunocompromised Children, Including Those With Sickle Cell Disease.

Background: Gut microbial diversity and composition play important roles in health. This cross-sectional study was designed to test the hypothesis that hospitalized children who may be relatively immunocompromised (IC), defined as those with cancer, sickle cell disease (SCD), transplantation, or receiving immunosuppressive therapy) would have decreased microbial diversity, increased Clostridioides difficile colonization and different species composition compared to non-immunocompromised (Non-IC) children admitted to the same pediatric unit. Methods: A stool sample was obtained within 72 h of admission to a single unit at The Children\u27s Hospital at Montefiore, Bronx, NY from March 2016 to February 2017 and the microbiome assessed by 16S rRNA sequencing. C. difficile colonization was assessed by glutamate dehydrogenase antigen and toxin polymerase chain reaction assays. Results: Stool samples were obtained from 69 IC (32 SCD, 19 cancer, 9 transplantation and 9 other) and 37 Non-IC patients. There were no significant differences in microbial alpha diversity and C. difficile colonization comparing IC vs. non-IC patients. Lower alpha diversity, however, was independently associated with the use of proton pump inhibitors or antibiotics, including prophylactic penicillin in patients with SCD. Differences in specific species abundances were observed when comparing IC vs. non-IC patients, particularly children with SCD. Non-IC patients had increased abundance of commensals associated with health including Alistipes putredinis, Alistipes ihumii, Roseburia inulinivorans, Roseburia intestinalis, and Ruminococcus albus (p \u3c 0.005). Conclusions: Antibiotics and proton pump inhibitors, which were more commonly used in IC children, were identified as risk factors for lower microbial diversity. Non-IC patients had higher abundance of several bacterial species associated with health. Longitudinal studies are needed to determine the clinical significance of these differences in gut microbiome

How effects on health equity are assessed in systematic reviews of interventions.

BACKGROUND: Enhancing health equity has now achieved international political importance with endorsement from the World Health Assembly in 2009.  The failure of systematic reviews to consider effects on health equity is cited by decision-makers as a limitation to their ability to inform policy and program decisions.  OBJECTIVES: To systematically review methods to assess effects on health equity in systematic reviews of effectiveness. SEARCH STRATEGY: We searched the following databases up to July 2 2010: MEDLINE, PsychINFO, the Cochrane Methodology Register, CINAHL, Education Resources Information Center, Education Abstracts, Criminal Justice Abstracts, Index to Legal Periodicals, PAIS International, Social Services Abstracts, Sociological Abstracts, Digital Dissertations and the Health Technology Assessment Database. We searched SCOPUS to identify articles that cited any of the included studies on October 7 2010. SELECTION CRITERIA: We included empirical studies of cohorts of systematic reviews that assessed methods for measuring effects on health inequalities. DATA COLLECTION AND ANALYSIS: Data were extracted using a pre-tested form by two independent reviewers. Risk of bias was appraised for included studies according to the potential for bias in selection and detection of systematic reviews.  MAIN RESULTS: Thirty-four methodological studies were included.  The methods used by these included studies were: 1) Targeted approaches (n=22); 2) gap approaches (n=12) and gradient approach (n=1).  Gender or sex was assessed in eight out of 34 studies, socioeconomic status in ten studies, race/ethnicity in seven studies, age in seven studies, low and middle income countries in 14 studies, and two studies assessed multiple factors across health inequity may exist.Only three studies provided a definition of health equity. Four methodological approaches to assessing effects on health equity were identified: 1) descriptive assessment of reporting and analysis in systematic reviews (all 34 studies used a type of descriptive method); 2) descriptive assessment of reporting and analysis in original trials (12/34 studies); 3) analytic approaches (10/34 studies); and 4) applicability assessment (11/34 studies). Both analytic and applicability approaches were not reported transparently nor in sufficient detail to judge their credibility. AUTHORS' CONCLUSIONS: There is a need for improvement in conceptual clarity about the definition of health equity, describing sufficient detail about analytic approaches (including subgroup analyses) and transparent reporting of judgments required for applicability assessments in order to assess and report effects on health equity in systematic reviews