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931.
Terahertz Emission: Terahertz Emission from Hybrid Perovskites Driven by Ultrafast Charge Separation and Strong Electron–Phonon Coupling (Adv. Mater. 11/2018) 下载免费PDF全文
932.
Lower C‐reactive protein and better hemodialysis survival are associated with regular exercise activity: Longitudinal outcomes from the ACTIVE‐ADIPOSE special study 下载免费PDF全文
Nancy G. Kutner PhD Rebecca Zhang MS Yijian Huang PhD George A. Kaysen MD PhD Jeanie Park MD 《Hemodialysis international. International Symposium on Home Hemodialysis》2016,20(3):473-483
Introduction Cross‐sectional and longitudinal studies in the general population have shown that a physically active lifestyle may have anti‐inflammatory properties, but evidence from studies conducted with maintenance hemodialysis (HD) patients is limited. Methods A multicenter prospective cohort of 755 HD participants aged 20–92 was evaluated in a USRDS special study 2009–2013. Kilocalories/week (kcal/week) of leisure time physical activity (LTPA) was estimated from the Minnesota Leisure Time Activity questionnaire. Predialysis serum samples were obtained concurrent with LTPA report date. Generalized estimating equations (GEE) examined association of participants’ LTPA and log‐normalized CRP across 24 months. Cox proportional hazards models investigated LTPA and survival over a median follow‐up of 718 days. Findings Baseline median CRP concentration was lower for participants with 500+ kcal/week LTPA vs. those with <500 kcal/week LTPA (3.4 mg/L vs. 4.6 mg/L; P = 0.03). Participants who reported lower LTPA (<500 kcal/week) at both baseline and 12 months had a borderline significant increase in CRP concentration (within‐group change 4.8 [1.9–10.4] to 5.8 [1.6–15.7]; P = 0.08). Lower LTPA was associated with higher log CRP over 24 months in adjusted GEE analyses (β coefficient = 0.16 [95% CI 0.02–0.31]; P = 0.03). 67/364 (18%) and 43/391 (11%) deaths occurred, respectively, among participants reporting <500 vs. 500+ kcal/week LTPA [adjusted mortality hazard ratio 1.63 (CI, 1.07, 2.47)]. Discussion The data suggest that increased estimated levels of LTPA, a physical activity/exercise opportunity widely applicable to HD patients, may be associated with lower CRP concentration as well as better survival outcome. 相似文献
933.
Judith L. Klavans Carolyn Sheffield Eileen Abels Jimmy Lin Rebecca Passonneau Tandeep Sidhu Dagobert Soergel 《Multimedia Tools and Applications》2009,42(1):115-138
In this paper, we present a system using computational linguistic techniques to extract metadata for image access. We discuss
the implementation, functionality and evaluation of an image catalogers’ toolkit, developed in the Computational Linguistics
for Metadata Building (CLiMB) research project. We have tested components of the system, including phrase finding for the
art and architecture domain, functional semantic labeling using machine learning, and disambiguation of terms in domain-specific
text vis a vis a rich thesaurus of subject terms, geographic and artist names. We present specific results on disambiguation
techniques and on the nature of the ambiguity problem given the thesaurus, resources, and domain-specific text resource, with
a comparison of domain-general resources and text. Our primary user group for evaluation has been the cataloger expert with
specific expertise in the fields of painting, sculpture, and vernacular and landscape architecture.
Judith L. Klavans is a Senior Research Scientist at the University of Maryland Institute for Advanced Computer Studies (UMIACS), and Principal Investigator on the Mellon-funded Computational Linguistics for Metadata Building (CLiMB) and IMLS-supported T3 research projects. Her research includes text-mining from corpora and dictionaries, disambiguation, and multilingual multidocument summarization. Previously, she directed the Center for Research on Information Access at Columbia University. Carolyn Sheffield holds an M.L.S. from the University of Maryland and her research interests include access issues surrounding visual and time-based materials. She designs, conducts and analyzes the CLiMB user studies and works closely with image catalogers to ensure that the CLiMB system reflects their needs and workflow. Eileen Abels is Masters’ Program Director and Professor in the College of Information Science and Technology at Drexel University. Prior to joining Drexel in January 2007, Dr. Abels spent more than 15 years at the College of Information Studies at the University of Maryland. Her research focuses on user needs and information behaviors. She works with a broad range of information users including translators, business school students and faculty, engineers, scientists, and members of the general public. Dr. Abels holds a PhD from the University of California, Los Angeles. Jimmy Lin’s research interests lie at the intersection of natural language processing and information retrieval. His work integrates knowledge- and data-driven approaches to address users’ information needs. Rebecca J. Passonneau is a Research Scientist at the Center for Computational Learning Systems, Columbia University. Her areas of interest include linking empirical research methods on corpora with computational models of language processing, the intersection of language and context in semantics and pragmatics, corpus design and analysis, and evaluation methods for NLP. Her current projects involve working with machine learning for the Consolidated Edison utility company, and designing an experimental dialog system to take patron book orders by phone for the Andrew Heiskell Braille and Talking Book library. Tandeep Sidhu is the Software Developer and Research Assistant for the CLiMB project. He is incharge of designing the CLiMB Toolkit as well as the NLP modules behind the Toolkit. He is currently pursuing his MS degree in Computer Science. Dagobert Soergel has been teaching information organization at the University of Maryland since 1970 and is an internationally known expert in Knowledge Organization Systems and in Digital Libraries. In the CLiMB project he served as general consultant and was specially involved in the design of study on the relationship between an image and cataloging terms assigned to it. 相似文献
Carolyn SheffieldEmail: |
Judith L. Klavans is a Senior Research Scientist at the University of Maryland Institute for Advanced Computer Studies (UMIACS), and Principal Investigator on the Mellon-funded Computational Linguistics for Metadata Building (CLiMB) and IMLS-supported T3 research projects. Her research includes text-mining from corpora and dictionaries, disambiguation, and multilingual multidocument summarization. Previously, she directed the Center for Research on Information Access at Columbia University. Carolyn Sheffield holds an M.L.S. from the University of Maryland and her research interests include access issues surrounding visual and time-based materials. She designs, conducts and analyzes the CLiMB user studies and works closely with image catalogers to ensure that the CLiMB system reflects their needs and workflow. Eileen Abels is Masters’ Program Director and Professor in the College of Information Science and Technology at Drexel University. Prior to joining Drexel in January 2007, Dr. Abels spent more than 15 years at the College of Information Studies at the University of Maryland. Her research focuses on user needs and information behaviors. She works with a broad range of information users including translators, business school students and faculty, engineers, scientists, and members of the general public. Dr. Abels holds a PhD from the University of California, Los Angeles. Jimmy Lin’s research interests lie at the intersection of natural language processing and information retrieval. His work integrates knowledge- and data-driven approaches to address users’ information needs. Rebecca J. Passonneau is a Research Scientist at the Center for Computational Learning Systems, Columbia University. Her areas of interest include linking empirical research methods on corpora with computational models of language processing, the intersection of language and context in semantics and pragmatics, corpus design and analysis, and evaluation methods for NLP. Her current projects involve working with machine learning for the Consolidated Edison utility company, and designing an experimental dialog system to take patron book orders by phone for the Andrew Heiskell Braille and Talking Book library. Tandeep Sidhu is the Software Developer and Research Assistant for the CLiMB project. He is incharge of designing the CLiMB Toolkit as well as the NLP modules behind the Toolkit. He is currently pursuing his MS degree in Computer Science. Dagobert Soergel has been teaching information organization at the University of Maryland since 1970 and is an internationally known expert in Knowledge Organization Systems and in Digital Libraries. In the CLiMB project he served as general consultant and was specially involved in the design of study on the relationship between an image and cataloging terms assigned to it. 相似文献
934.
Michael V. Yudelson Olga P. Medvedeva Rebecca S. Crowley 《User Modeling and User-Adapted Interaction》2008,18(4):349-382
Creating student models for Intelligent Tutoring Systems (ITS) in novel domains is often a difficult task. In this study,
we outline a multifactor approach to evaluating models that we developed in order to select an appropriate student model for
our medical ITS. The combination of areas under the receiver-operator and precision-recall curves, with residual analysis,
proved to be a useful and valid method for model selection. We improved on Bayesian Knowledge Tracing with models that treat
help differently from mistakes, model all attempts, differentiate skill classes, and model forgetting. We discuss both the
methodology we used and the insights we derived regarding student modeling in this novel domain.
相似文献
Rebecca S. Crowley (Corresponding author)Email: |
935.
Amay J. Bandodkar Jungil Choi Stephen P. Lee William J. Jeang Prophecy Agyare Philipp Gutruf Siqing Wang Rebecca A. Sponenburg Jonathan T. Reeder Stephanie Schon Tyler R. Ray Shulin Chen Sunita Mehta Savanna Ruiz John A. Rogers 《Advanced materials (Deerfield Beach, Fla.)》2019,31(32)
Comprehensive analysis of sweat chemistry provides noninvasive health monitoring capabilities that complement established biophysical measurements such as heart rate, blood oxygenation, and body temperature. Recent developments in skin‐integrated soft microfluidic systems address many challenges associated with standard technologies in sweat collection and analysis. However, recording of time‐dependent variations in sweat composition requires bulky electronic systems and power sources, thereby constraining form factor, cost, and modes of use. Here, presented are unconventional design concepts, materials, and device operation principles that address this challenge. Flexible galvanic cells embedded within skin‐interfaced microfluidics with passive valves serve as sweat‐activated “stopwatches” that record temporal information associated with collection of discrete microliter volumes of sweat. The result allows for precise measurements of dynamic sweat composition fluctuations using in situ or ex situ analytical techniques. Integrated electronics based on near‐field communication (NFC) protocols or docking stations equipped with standard electronic measurement tools provide means for extracting digital timing results from the stopwatches. Human subject studies of time‐stamped sweat samples by in situ colorimetric methods and ex situ techniques based on inductively coupled plasma mass spectroscopy (ICP‐MS) and chlorodimetry illustrate the ability to quantitatively capture time‐dynamic sweat chemistry in scenarios compatible with field use. 相似文献
936.
Utku M. Sonmez Stephen Coyle Rebecca E. Taylor Philip R. LeDuc 《Small (Weinheim an der Bergstrasse, Germany)》2020,16(16)
Soft lithography enables rapid microfabrication of many types of microsystems by replica molding elastomers into master molds. However, master molds can be very costly, hard to fabricate, vulnerable to damage, and have limited casting life. Here, an approach for the multiplication of master molds into monolithic thermoplastic sheets for further soft lithographic fabrication is introduced. The technique is tested with master molds fabricated through photolithography, mechanical micromilling as well as 3D printing, and the results are demonstrated. Microstructures with submicron feature sizes and high aspect ratios are successfully copied. The copying fidelity of the technique is quantitatively characterized and the microfluidic devices fabricated through this technique are functionally tested. This approach is also used to combine different master molds with up to 19 unique geometries into a single monolithic copy mold in a single step displaying the effectiveness of the copying technique over a large footprint area to scale up the microfabrication. This microfabrication technique can be performed outside the cleanroom without using any sophisticated equipment, suggesting a simple way for high‐throughput rigid monolithic mold fabrication that can be used in analytical chemistry studies, biomedical research, and microelectromechanical systems. 相似文献
937.
Fatemeh Naderi Mehr Dmitry Grigoriev Rebecca Heaton Joshua Baptiste Anthony J. Stace Nikolay Puretskiy Elena Besley Alexander Bker 《Small (Weinheim an der Bergstrasse, Germany)》2020,16(14)
A directed attractive interaction between predefined “patchy” sites on the surfaces of anisotropic microcolloids can provide them with the ability to self‐assemble in a controlled manner to build target structures of increased complexity. An important step toward the controlled formation of a desired superstructure is to identify reversible electrostatic interactions between patches which allow them to align with one another. The formation of bipatchy particles with two oppositely charged patches fabricated using sandwich microcontact printing is reported. These particles spontaneously self‐aggregate in solution, where a diversity of short and long chains of bipatchy particles with different shapes, such as branched, bent, and linear, are formed. Calculations show that chain formation is driven by a combination of attractive electrostatic interactions between oppositely charged patches and the charge‐induced polarization of interacting particles. 相似文献
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940.
Rader JS Malone JP Gross J Gilmore P Brooks RA Nguyen L Crimmins DL Feng S Wright JD Taylor N Zighelboim I Funk MC Huettner PC Ladenson JH Gius D Townsend RR 《Proteomics. Clinical applications》2008,2(12):1658-1669
Cervical cancer screening is ideally suited for the development of biomarkers due to the ease of tissue acquisition and the well-established histological transitions. Furthermore, cell and biologic fluid obtained from cervix samples undergo specific molecular changes that can be profiled. However, the ideal manner and techniques for preparing cervical samples remains to be determined. To address this critical issue a patient screening protein and nucleic acid collection protocol was established. RNAlater was used to collect the samples followed by proteomic methods to identify proteins that were differentially expressed in normal cervical epithelial versus cervical cancer cells. Three hundred ninety spots were identified via 2-D DIGE that were expressed at either higher or lower levels (>three-fold) in cervical cancer samples. These proteomic results were compared to genes in a cDNA microarray analysis of microdissected neoplastic cervical specimens to identify overlapping patterns of expression. The most frequent pathways represented by the combined dataset were: cell cycle: G2/M DNA damage checkpoint regulation; aryl hydrocarbon receptor signaling; p53 signaling; cell cycle: G1/S checkpoint regulation; and the ER stress pathway. HNRPA2B1 was identified as a biomarker candidate with increased expression in cancer compared to normal cervix and validated by Western blot. 相似文献