9,121 research outputs found
Topic supervised non-negative matrix factorization
Topic models have been extensively used to organize and interpret the
contents of large, unstructured corpora of text documents. Although topic
models often perform well on traditional training vs. test set evaluations, it
is often the case that the results of a topic model do not align with human
interpretation. This interpretability fallacy is largely due to the
unsupervised nature of topic models, which prohibits any user guidance on the
results of a model. In this paper, we introduce a semi-supervised method called
topic supervised non-negative matrix factorization (TS-NMF) that enables the
user to provide labeled example documents to promote the discovery of more
meaningful semantic structure of a corpus. In this way, the results of TS-NMF
better match the intuition and desired labeling of the user. The core of TS-NMF
relies on solving a non-convex optimization problem for which we derive an
iterative algorithm that is shown to be monotonic and convergent to a local
optimum. We demonstrate the practical utility of TS-NMF on the Reuters and
PubMed corpora, and find that TS-NMF is especially useful for conceptual or
broad topics, where topic key terms are not well understood. Although
identifying an optimal latent structure for the data is not a primary objective
of the proposed approach, we find that TS-NMF achieves higher weighted Jaccard
similarity scores than the contemporary methods, (unsupervised) NMF and latent
Dirichlet allocation, at supervision rates as low as 10% to 20%
Anna Marie D\u27Amico
Dr. D’Amico entered Jefferson Medical College in 1968 after spending three years as a biology major at Catholic University of America in Washington D.C. After graduating from Jefferson in 1972 she did her internship and residency at Wilmington General Hospital before going into practice on her own in 1976. Dr. D’Amico retired from practice in 2007. Since then she has volunteered at the Claymont Family Health Clinic, a clinic for the uninsured, and from 2009-2011 she was the Medical Director of Planned Parenthood of Delaware. Most recently she is the Medical Director of a new medical spa.
Dr. D’Amico has been professionally involved in ACOG, the American Congress of Obstetricians and Gynecologists, for more than twenty years and has held a variety of leadership positions in the organization, most notably as the first woman District III Chair from 2004-2007.https://jdc.jefferson.edu/oral_histories/1007/thumbnail.jp
Ion-water clusters, bulk medium effects, and ion hydration
Thermochemistry of gas-phase ion-water clusters together with estimates of
the hydration free energy of the clusters and the water ligands are used to
calculate the hydration free energy of the ion. Often the hydration
calculations use a continuum model of the solvent. The primitive quasichemical
approximation to the quasichemical theory provides a transparent framework to
anchor such efforts. Here we evaluate the approximations inherent in the
primitive quasichemical approach and elucidate the different roles of the bulk
medium. We find that the bulk medium can stabilize configurations of the
cluster that are usually not observed in the gas phase, while also
simultaneously lowering the excess chemical potential of the ion. This effect
is more pronounced for soft ions. Since the coordination number that minimizes
the excess chemical potential of the ion is identified as the optimal or most
probable coordination number, for such soft ions, the optimum cluster size and
the hydration thermodynamics obtained without account of the bulk medium on the
ion-water clustering reaction can be different from those observed in
simulations of the aqueous ion. The ideas presented in this work are expected
to be relevant to experimental studies that translate thermochemistry of
ion-water clusters to the thermodynamics of the hydrated ion and to evolving
theoretical approaches that combine high-level calculations on clusters with
coarse-grained models of the medium
Cultures and Communities in the Virtual World: Beginning the Exploration
Most of today's college students grew up as part of the Net Generation(Cooke-Plagwitz, 2009), and pedagogues may assume that motivatedstudents use technologies outside of class to improve their target languageskills. However, little research has been conducted to see how studentsactually use technology to engage with foreign cultures and communitiesbeyond the classroom setting. This exploratory study draws from bothquantitative and qualitative data sets to reveal the ways first-semesterstudents use technology to learn about German-speaking cultures andcommunities, and using Dörnyei's L2 Motivational Self System (2005 &2009), also shows how students' out-of-class learning via technologyrelates to their diverse motivations as language learners. Discussionincludes suggestions for exploring cultures and communities throughdigital tools both within and beyond the classroom setting
Investigation of smooth specimen scc test procedures; variations in environment, specimen size, stressing frame, and stress state
The variables studied in the stress-corrosion cracking performance of high strength aluminum alloys were: (1) corrosiveness of the environment, (2) specimen size and stiffness of the stressing system, (3) interpretation of transgranular cracking, and (4) interaction of the state of stress and specimen orientation in a product with an anisotropic grain structure. It was shown that the probability of failure and time to fracture for a specimen loaded in direct tension are influenced by corrosion pattern, the stressing assembly stiffness, and the notch tensile strength of the alloy. Results demonstrate that the combination of a normal tension stress and a shear stress acting on the plane of maximum susceptibility in a product with a highly directional grain cause the greatest tendency for stress-corrosion cracking
Differential Effects of Reduced Foot Sole Sensitivity and Nerve Conduction Velocity on Postural Control and Functional Gait
INTRODUCTION: Peripheral neuropathy is characterized by a loss of foot sole sensitivity and slowed nerve conduction velocity. Individuals with peripheral neuropathy have decreased postural control ability and functional gait performance. No research was found that differentiated the effects of the main symptoms of peripheral neuropathy on postural control and functional gait. PURPOSE: The purpose of this study was to assess the differential effects of reduced foot sole sensitivity and slowed nerve conduction velocity on postural control and functional gait. METHODS: Two main clinical symptoms, H-index and foot sole sensitivity were evaluated among 35 participants. Outcome variables are the center of pressure standard deviation in the anteroposterior direction (SDAP) and the center of pressure average velocity (Vavg) during 30 seconds eyes open quiet standing, 6-minute walk distance (6MWD), and timed-up-and-go duration (TUG). RESULTS: Participants were separated into three groups symptomologically: Less affected (LA, 73±2 years old, 68.4±3.5kg, 1.62±0.02m, H-index: 89.7±3.4, range 78.0-109.4, cm2/ms2, Foot sole sensitivity score: 8.6±0.5, range 6-10), moderately affected (MA, 74±2 years old, 77.2±4.1kg, 1.65±0.02m, H-index: 60.2±3.4, range 42.8-76-6, cm2/ms2, Foot sole sensitivity score: 8.7±0.5, range 6-10), and severely affected (SA, 73±1 years old, 95.2±6.5kg, 1.73±0.03m, H-index: 61.8±2.1, range 45.6-75.5, cm2/ms2, Foot sole sensitivity score: 2.2±0.6, range 0-5). Multivariate analysis revealed significant group differences (
The Elementary School Climate and Teacher Self-Esteem: A Study of Potential Relationship
The factors of self-esteem and the school climate have been independently studied for over a century and have been found as universal factors of importance. This study investigates the potential relationship between teacher self-esteem and the school climate. Fifty-nine elementary school teachers at public schools in the Midwest participated in a survey consisting of demographic information, self-esteem assessment, and a school climate inventory. The findings showed a moderate relationship between teacher self-esteem and the school climate. Additional sub-categories of relationships and teaching learning indicated moderate relationships with teacher self-esteem. These findings lead to suggestions for improving factors in the school climate including incorporating a positive-based intervention and support program. Suggestions for implementing inclusive and person-centered policies and procedures at school level, local, state, and federal levels and development of growth-based evaluations and supports for new teachers are explored. Other suggestions include additional research and testing on the newly designed school climate inventory which Cronbach\u27s alpha of .863 indicated high reliability and further research on the multi-factored relationship between teacher self-esteem and the school climate
Occupational Burnout and the Causes, Predisposing Factors, Consequences, and Prevention Strategies
Occupational burnout is a common dilemma for employees working in long term careers. It is characterized by exhaustion, cynicism, and lowered efficiency, and it progresses through three stages. Burnout is caused by the increase of demands and the loss of resources. Sleep impairment is also significantly associated with burnout, and also has been shown to hinder the recovery. Lack of balance between work and personal life, as well as perception of stressful events can lead to developing feelings of burnout. External regulation has been associated with a person being more susceptible to develop burnout. Other personal characteristics, such as inability to handle stress, pessimism, and frequently feeling fatigued can result in a person being more susceptible to burnout. Failing to address feelings of burnout properly can result in a variety of negative consequences in the workplace, home life, and personal health. Employees can prevent burnout by balancing their work lives with their personal lives, and keep up with their personal health. In the workplace, employees should reevaluate their goals regularly and prioritize their tasks into manageable lists. Being aware of the predisposition, causes, and symptoms of occupational burnout will help us to recognize and prevent it, and help employees to feel more motivated and accomplished in their careers
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