ERIC Educational Resources Information Center
Seamster, Christina Lambert
2016-01-01
According to Molnar (2014), full time virtual school education lacks a measurement tool that accurately measures effective virtual teacher practice. Using both qualitative and quantitative methods, the current study sought to understand the common practices among full time K-8 virtual school teachers, the extent to which teachers believed such…
Ethical Climate, Organizational Commitment, and Job Satisfaction of Full-Time Faculty Members
ERIC Educational Resources Information Center
Moore, Heather Louise
2012-01-01
The purpose of this quantitative study was to better understand the relationship of perceived ethical climate on the organizational commitment and job satisfaction of full-time faculty members in institutions of higher education. Full-time faculty members are the forefront employees of any educational institution, and they have a direct impact on…
Thoma, Brent; Camorlinga, Paola; Chan, Teresa M; Hall, Andrew Koch; Murnaghan, Aleisha; Sherbino, Jonathan
2018-01-01
Quantitative research is one of the many research methods used to help educators advance their understanding of questions in medical education. However, little research has been done on how to succeed in publishing in this area. We conducted a scoping review to identify key recommendations and reporting guidelines for quantitative educational research and scholarship. Medline, ERIC, and Google Scholar were searched for English-language articles published between 2006 and January 2016 using the search terms, "research design," "quantitative," "quantitative methods," and "medical education." A hand search was completed for additional references during the full-text review. Titles/abstracts were reviewed by two authors (BT, PC) and included if they focused on quantitative research in medical education and outlined reporting guidelines, or provided recommendations on conducting quantitative research. One hundred articles were reviewed in parallel with the first 30 used for calibration and the subsequent 70 to calculate Cohen's kappa coefficient. Two reviewers (BT, PC) conducted a full text review and extracted recommendations and reporting guidelines. A simple thematic analysis summarized the extracted recommendations. Sixty-one articles were reviewed in full, and 157 recommendations were extracted. The thematic analysis identified 86 items, 14 categories, and 3 themes. Fourteen quality evaluation tools and reporting guidelines were found. Discussion This paper provides guidance for junior researchers in the form of key quality markers and reporting guidelines. We hope that quantitative researchers in medical education will be informed by the results and that further work will be done to refine the list of recommendations.
Community, know thyself: caring about place.
Sally Duncan
2000-01-01
Traditional scientific assessments have limitations in providing full understanding of the potential impacts forest management has on communities. Much of the knowledge communities have of themselves is inaccessible to quantitative methods but can be provided through participatory processes, or what is termed "civic science." Self-assessment by communities,...
Quantitative Literacy: Geosciences and Beyond
NASA Astrophysics Data System (ADS)
Richardson, R. M.; McCallum, W. G.
2002-12-01
Quantitative literacy seems like such a natural for the geosciences, right? The field has gone from its origin as a largely descriptive discipline to one where it is hard to imagine failing to bring a full range of mathematical tools to the solution of geological problems. Although there are many definitions of quantitative literacy, we have proposed one that is analogous to the UNESCO definition of conventional literacy: "A quantitatively literate person is one who, with understanding, can both read and represent quantitative information arising in his or her everyday life." Central to this definition is the concept that a curriculum for quantitative literacy must go beyond the basic ability to "read and write" mathematics and develop conceptual understanding. It is also critical that a curriculum for quantitative literacy be engaged with a context, be it everyday life, humanities, geoscience or other sciences, business, engineering, or technology. Thus, our definition works both within and outside the sciences. What role do geoscience faculty have in helping students become quantitatively literate? Is it our role, or that of the mathematicians? How does quantitative literacy vary between different scientific and engineering fields? Or between science and nonscience fields? We will argue that successful quantitative literacy curricula must be an across-the-curriculum responsibility. We will share examples of how quantitative literacy can be developed within a geoscience curriculum, beginning with introductory classes for nonmajors (using the Mauna Loa CO2 data set) through graduate courses in inverse theory (using singular value decomposition). We will highlight six approaches to across-the curriculum efforts from national models: collaboration between mathematics and other faculty; gateway testing; intensive instructional support; workshops for nonmathematics faculty; quantitative reasoning requirement; and individual initiative by nonmathematics faculty.
ERIC Educational Resources Information Center
Klinkenberg, Laurel Beth
2013-01-01
In recent years, community colleges have come into the spotlight nationally in terms of their potential to assist in the revitalization of the economy. This has resulted in an increased need for community colleges to understand more fully the factors that influence student persistence. The purpose of this quasi-experimental study was to…
Full 3-D OCT-based pseudophakic custom computer eye model
Sun, M.; Pérez-Merino, P.; Martinez-Enriquez, E.; Velasco-Ocana, M.; Marcos, S.
2016-01-01
We compared measured wave aberrations in pseudophakic eyes implanted with aspheric intraocular lenses (IOLs) with simulated aberrations from numerical ray tracing on customized computer eye models, built using quantitative 3-D OCT-based patient-specific ocular geometry. Experimental and simulated aberrations show high correlation (R = 0.93; p<0.0001) and similarity (RMS for high order aberrations discrepancies within 23.58%). This study shows that full OCT-based pseudophakic custom computer eye models allow understanding the relative contribution of optical geometrical and surgically-related factors to image quality, and are an excellent tool for characterizing and improving cataract surgery. PMID:27231608
Full-range public health leadership, part 1: quantitative analysis.
Carlton, Erik L; Holsinger, James W; Riddell, Martha; Bush, Heather
2015-01-01
Workforce and leadership development are central to the future of public health. However, public health has been slow to translate and apply leadership models from other professions and to incorporate local perspectives in understanding public health leadership. This study utilized the full-range leadership model in order to examine public health leadership. Specifically, it sought to measure leadership styles among local health department directors and to understand the context of leadership in local health departments. Leadership styles among local health department directors (n = 13) were examined using survey methodology. Quantitative analysis methods included descriptive statistics, boxplots, and Pearson bivariate correlations using SPSS v18.0. Self-reported leadership styles were highly correlated to leadership outcomes at the organizational level. However, they were not related to county health rankings. Results suggest the preeminence of leader behaviors and providing individual consideration to staff as compared to idealized attributes of leaders, intellectual stimulation, or inspirational motivation. Holistic leadership assessment instruments such as the multifactor leadership questionnaire can be useful in assessing public health leaders' approaches and outcomes. Comprehensive, 360-degree reviews may be especially helpful. Further research is needed to examine the effectiveness of public health leadership development models, as well as the extent that public health leadership impacts public health outcomes.
Gomez-Ramirez, Jaime; Sanz, Ricardo
2013-09-01
One of the most important scientific challenges today is the quantitative and predictive understanding of biological function. Classical mathematical and computational approaches have been enormously successful in modeling inert matter, but they may be inadequate to address inherent features of biological systems. We address the conceptual and methodological obstacles that lie in the inverse problem in biological systems modeling. We introduce a full Bayesian approach (FBA), a theoretical framework to study biological function, in which probability distributions are conditional on biophysical information that physically resides in the biological system that is studied by the scientist. Copyright © 2013 Elsevier Ltd. All rights reserved.
Chandel, Shubham; Soni, Jalpa; Ray, Subir kumar; Das, Anwesh; Ghosh, Anirudha; Raj, Satyabrata; Ghosh, Nirmalya
2016-01-01
Information on the polarization properties of scattered light from plasmonic systems are of paramount importance due to fundamental interest and potential applications. However, such studies are severely compromised due to the experimental difficulties in recording full polarization response of plasmonic nanostructures. Here, we report on a novel Mueller matrix spectroscopic system capable of acquiring complete polarization information from single isolated plasmonic nanoparticle/nanostructure. The outstanding issues pertaining to reliable measurements of full 4 × 4 spectroscopic scattering Mueller matrices from single nanoparticle/nanostructures are overcome by integrating an efficient Mueller matrix measurement scheme and a robust eigenvalue calibration method with a dark-field microscopic spectroscopy arrangement. Feasibility of quantitative Mueller matrix polarimetry and its potential utility is illustrated on a simple plasmonic system, that of gold nanorods. The demonstrated ability to record full polarization information over a broad wavelength range and to quantify the intrinsic plasmon polarimetry characteristics via Mueller matrix inverse analysis should lead to a novel route towards quantitative understanding, analysis/interpretation of a number of intricate plasmonic effects and may also prove useful towards development of polarization-controlled novel sensing schemes. PMID:27212687
A literature review of quantitative indicators to measure the quality of labor and delivery care.
Tripathi, Vandana
2016-02-01
Strengthening measurement of the quality of labor and delivery (L&D) care in low-resource countries requires an understanding of existing approaches. To identify quantitative indicators of L&D care quality and assess gaps in indicators. PubMed, CINAHL Plus, and Embase databases were searched for research published in English between January 1, 1990, and October 31, 2013, using structured terms. Studies describing indicators for L&D care quality assessment were included. Those whose abstracts contained inclusion criteria underwent full-text review. Study characteristics, including indicator selection and data sources, were extracted via a standard spreadsheet. The structured search identified 1224 studies. After abstract and full-text review, 477 were included in the analysis. Most studies selected indicators by using literature review, clinical guidelines, or expert panels. Few indicators were empirically validated; most studies relied on medical record review to measure indicators. Many quantitative indicators have been used to measure L&D care quality, but few have been validated beyond expert opinion. There has been limited use of clinical observation in quality assessment of care processes. The findings suggest the need for validated, efficient consensus indicators of the quality of L&D care processes, particularly in low-resource countries. Copyright © 2015 International Federation of Gynecology and Obstetrics. Published by Elsevier Ireland Ltd. All rights reserved.
Statistical thermodynamics unveils the dissolution mechanism of cellobiose.
Nicol, Thomas W J; Isobe, Noriyuki; Clark, James H; Shimizu, Seishi
2017-08-30
In the study of the cellulose dissolution mechanism opinion is still divided. Here, the solution interaction components of the most prominent hypotheses for the driving force of cellulose dissolution were evaluated quantitatively. Combining a rigorous statistical thermodynamic theory and cellobiose solubility data in the presence of chloride salts, whose cations progress in the Hofmeister series (KCl, NaCl, LiCl and ZnCl 2 ), we have shown that cellobiose solubilization is driven by the preferential accumulation of salts around the solutes which is stronger than cellobiose hydration. Yet contrary to the classical chaotropy hypothesis, increasing salt concentration leads to cellobiose dehydration in the presence of the strongest solubilizer ZnCl 2 . However, thanks to cellobiose dehydration, cellobiose-salt interaction still remains preferential despite weakening salt accumulation. Based on such insights, the previous hypotheses based on hydrophobicity and polymer charging have also been evaluated quantitatively. Thus, our present study successfully paved a way towards identifying the basic driving forces for cellulose solubilization in a quantitative manner for the first time. When combined with unit additivity methods this quantitative information could lead to a full understanding of cellulose solubility.
Leadership and Culture-Building in Schools: Quantitative and Qualitative Understandings.
ERIC Educational Resources Information Center
Sashkin, Marshall; Sashkin, Molly G.
Understanding effective school leadership as a function of culture building through quantitative and qualitative analyses is the purpose of this paper. The two-part quantitative phase of the research focused on statistical measures of culture and leadership behavior directed toward culture building in the school. The first quantitative part…
Physiologic Basis for Understanding Quantitative Dehydration Assessment
2012-01-01
Perspective Physiologic basis for understanding quantitative dehydration assessment1–4 Samuel N Cheuvront, Robert W Kenefick, Nisha Charkoudian, and...Michael N Sawka ABSTRACT Dehydration (body water deficit) is a physiologic state that can have profound implications for human health and performance...review the physiologic basis for understanding quantitative dehydration as- sessment. We highlight how phenomenologic interpretations of de- hydration
Live cell refractometry using Hilbert phase microscopy and confocal reflectance microscopy.
Lue, Niyom; Choi, Wonshik; Popescu, Gabriel; Yaqoob, Zahid; Badizadegan, Kamran; Dasari, Ramachandra R; Feld, Michael S
2009-11-26
Quantitative chemical analysis has served as a useful tool for understanding cellular metabolisms in biology. Among many physical properties used in chemical analysis, refractive index in particular has provided molecular concentration that is an important indicator for biological activities. In this report, we present a method of extracting full-field refractive index maps of live cells in their native states. We first record full-field optical thickness maps of living cells by Hilbert phase microscopy and then acquire physical thickness maps of the same cells using a custom-built confocal reflectance microscope. Full-field and axially averaged refractive index maps are acquired from the ratio of optical thickness to physical thickness. The accuracy of the axially averaged index measurement is 0.002. This approach can provide novel biological assays of label-free living cells in situ.
Live Cell Refractometry Using Hilbert Phase Microscopy and Confocal Reflectance Microscopy†
Lue, Niyom; Choi, Wonshik; Popescu, Gabriel; Yaqoob, Zahid; Badizadegan, Kamran; Dasari, Ramachandra R.; Feld, Michael S.
2010-01-01
Quantitative chemical analysis has served as a useful tool for understanding cellular metabolisms in biology. Among many physical properties used in chemical analysis, refractive index in particular has provided molecular concentration that is an important indicator for biological activities. In this report, we present a method of extracting full-field refractive index maps of live cells in their native states. We first record full-field optical thickness maps of living cells by Hilbert phase microscopy and then acquire physical thickness maps of the same cells using a custom-built confocal reflectance microscope. Full-field and axially averaged refractive index maps are acquired from the ratio of optical thickness to physical thickness. The accuracy of the axially averaged index measurement is 0.002. This approach can provide novel biological assays of label-free living cells in situ. PMID:19803506
Hogstrom, L. J.; Guo, S. M.; Murugadoss, K.; Bathe, M.
2016-01-01
Brain function emerges from hierarchical neuronal structure that spans orders of magnitude in length scale, from the nanometre-scale organization of synaptic proteins to the macroscopic wiring of neuronal circuits. Because the synaptic electrochemical signal transmission that drives brain function ultimately relies on the organization of neuronal circuits, understanding brain function requires an understanding of the principles that determine hierarchical neuronal structure in living or intact organisms. Recent advances in fluorescence imaging now enable quantitative characterization of neuronal structure across length scales, ranging from single-molecule localization using super-resolution imaging to whole-brain imaging using light-sheet microscopy on cleared samples. These tools, together with correlative electron microscopy and magnetic resonance imaging at the nanoscopic and macroscopic scales, respectively, now facilitate our ability to probe brain structure across its full range of length scales with cellular and molecular specificity. As these imaging datasets become increasingly accessible to researchers, novel statistical and computational frameworks will play an increasing role in efforts to relate hierarchical brain structure to its function. In this perspective, we discuss several prominent experimental advances that are ushering in a new era of quantitative fluorescence-based imaging in neuroscience along with novel computational and statistical strategies that are helping to distil our understanding of complex brain structure. PMID:26855758
Understanding Pre-Quantitative Risk in Projects
NASA Technical Reports Server (NTRS)
Cooper, Lynne P.
2011-01-01
Standard approaches to risk management in projects depend on the ability of teams to identify risks and quantify the probabilities and consequences of these risks (e.g., the 5 x 5 risk matrix). However, long before quantification does - or even can - occur, and long after, teams make decisions based on their pre-quantitative understanding of risk. These decisions can have long-lasting impacts on the project. While significant research has looked at the process of how to quantify risk, our understanding of how teams conceive of and manage pre-quantitative risk is lacking. This paper introduces the concept of pre-quantitative risk and discusses the implications of addressing pre-quantitative risk in projects.
QACD: A method for the quantitative assessment of compositional distribution in geologic materials
NASA Astrophysics Data System (ADS)
Loocke, M. P.; Lissenberg, J. C. J.; MacLeod, C. J.
2017-12-01
In order to fully understand the petrogenetic history of a rock, it is critical to obtain a thorough characterization of the chemical and textural relationships of its mineral constituents. Element mapping combines the microanalytical techniques that allow for the analysis of major- and minor elements at high spatial resolutions (e.g., electron microbeam analysis) with 2D mapping of samples in order to provide unprecedented detail regarding the growth histories and compositional distributions of minerals within a sample. We present a method for the acquisition and processing of large area X-ray element maps obtained by energy-dispersive X-ray spectrometer (EDS) to produce a quantitative assessment of compositional distribution (QACD) of mineral populations within geologic materials. By optimizing the conditions at which the EDS X-ray element maps are acquired, we are able to obtain full thin section quantitative element maps for most major elements in relatively short amounts of time. Such maps can be used to not only accurately identify all phases and calculate mineral modes for a sample (e.g., a petrographic thin section), but, critically, enable a complete quantitative assessment of their compositions. The QACD method has been incorporated into a python-based, easy-to-use graphical user interface (GUI) called Quack. The Quack software facilitates the generation of mineral modes, element and molar ratio maps and the quantification of full-sample compositional distributions. The open-source nature of the Quack software provides a versatile platform which can be easily adapted and modified to suit the needs of the user.
Understanding quantitative research: part 1.
Hoe, Juanita; Hoare, Zoë
This article, which is the first in a two-part series, provides an introduction to understanding quantitative research, basic statistics and terminology used in research articles. Critical appraisal of research articles is essential to ensure that nurses remain up to date with evidence-based practice to provide consistent and high-quality nursing care. This article focuses on developing critical appraisal skills and understanding the use and implications of different quantitative approaches to research. Part two of this article will focus on explaining common statistical terms and the presentation of statistical data in quantitative research.
Biomarkers: Delivering on the expectation of molecularly driven, quantitative health.
Wilson, Jennifer L; Altman, Russ B
2018-02-01
Biomarkers are the pillars of precision medicine and are delivering on expectations of molecular, quantitative health. These features have made clinical decisions more precise and personalized, but require a high bar for validation. Biomarkers have improved health outcomes in a few areas such as cancer, pharmacogenetics, and safety. Burgeoning big data research infrastructure, the internet of things, and increased patient participation will accelerate discovery in the many areas that have not yet realized the full potential of biomarkers for precision health. Here we review themes of biomarker discovery, current implementations of biomarkers for precision health, and future opportunities and challenges for biomarker discovery. Impact statement Precision medicine evolved because of the understanding that human disease is molecularly driven and is highly variable across patients. This understanding has made biomarkers, a diverse class of biological measurements, more relevant for disease diagnosis, monitoring, and selection of treatment strategy. Biomarkers' impact on precision medicine can be seen in cancer, pharmacogenomics, and safety. The successes in these cases suggest many more applications for biomarkers and a greater impact for precision medicine across the spectrum of human disease. The authors assess the status of biomarker-guided medical practice by analyzing themes for biomarker discovery, reviewing the impact of these markers in the clinic, and highlight future and ongoing challenges for biomarker discovery. This work is timely and relevant, as the molecular, quantitative approach of precision medicine is spreading to many disease indications.
NASA Astrophysics Data System (ADS)
McDaniel, Mark A.; Stoen, Siera M.; Frey, Regina F.; Markow, Zachary E.; Hynes, K. Mairin; Zhao, Jiuqing; Cahill, Michael J.
2016-12-01
The existing literature indicates that interactive-engagement (IE) based general physics classes improve conceptual learning relative to more traditional lecture-oriented classrooms. Very little research, however, has examined quantitative problem-solving outcomes from IE based relative to traditional lecture-based physics classes. The present study included both pre- and post-course conceptual-learning assessments and a new quantitative physics problem-solving assessment that included three representative conservation of energy problems from a first-semester calculus-based college physics course. Scores for problem translation, plan coherence, solution execution, and evaluation of solution plausibility were extracted for each problem. Over 450 students in three IE-based sections and two traditional lecture sections taught at the same university during the same semester participated. As expected, the IE-based course produced more robust gains on a Force Concept Inventory than did the lecture course. By contrast, when the full sample was considered, gains in quantitative problem solving were significantly greater for lecture than IE-based physics; when students were matched on pre-test scores, there was still no advantage for IE-based physics on gains in quantitative problem solving. Further, the association between performance on the concept inventory and quantitative problem solving was minimal. These results highlight that improved conceptual understanding does not necessarily support improved quantitative physics problem solving, and that the instructional method appears to have less bearing on gains in quantitative problem solving than does the kinds of problems emphasized in the courses and homework and the overlap of these problems to those on the assessment.
Cyclic reconstruction of 4D retinal blood flow with pulse synchronization
NASA Astrophysics Data System (ADS)
Schmoll, Tilman; Lasser, Theo; Leitgeb, Rainer A.
2009-02-01
Doppler OCT systems allow nowadays to visualize quantitative and qualitative angiographic maps of retinal tissue. We equipped the instrument with a pulse oximeter and recorded the pulse synchronously with the resonant Doppler flow data. Recombination of tomograms according to the heart beat cycles yields full volumes for each cycle instant. We believe such multi-dimensional functional information and the ability to monitor dynamic processes over time to open exciting perspectives that ultimately contribute to a better understanding of retinal physiology and patho-physiology in-vivo.
ERIC Educational Resources Information Center
Campbell, Corbin M.
2017-01-01
This article describes quantitative observation as a method for understanding college educational experiences. Quantitative observation has been used widely in several fields and in K-12 education, but has had limited application to research in higher education and student affairs to date. The article describes the central tenets of quantitative…
Sibling recurrence and the genetic epidemiology of autism
Constantino, John N.; Zhang, Yi; Frazier, Thomas; Abbacchi, Anna M.; Law, Paul
2010-01-01
Objective Although the symptoms of autism exhibit quantitative distributions in nature, estimates of recurrence risk in families have never previously considered or incorporated quantitative characterization of the autistic phenotype among siblings. Method We report the results of quantitative characterization of 2,920 children from 1,235 families participating in a national volunteer register who met the criteria of having at least one child clinically-affected by an autism spectrum disorder (ASD) and at least one full biological sibling. Results The occurrence of a traditionally-defined ASD in an additional child occurred in 10.9% of the families. An additional 20% of non-ASD-affected siblings had a history of language delay, half of whom had exhibited autistic qualities of speech. Quantitative characterization using the Social Responsiveness Scale (SRS) supported previously-reported aggregation of a wide range of subclinical (quantitative) autistic traits among otherwise unaffected children in multiple-incidence families, and a relative absence of quantitative autistic traits among siblings in single-incidence autism families. Girls whose standardized severity ratings fell above a first percentile severity threshold (relative to the general population distribution) were significantly less likely to have elicited community diagnoses than their male counterparts. Conclusions These data suggest that, depending on how it is defined, sibling recurrence in ASD may exceed previously-published estimates, and varies as a function of family type. The results support differences in mechanisms of genetic transmission between simplex and multiplex autism, and advance current understanding of the genetic epidemiology of autism. PMID:20889652
CCTV Coverage Index Based on Surveillance Resolution and Its Evaluation Using 3D Spatial Analysis
Choi, Kyoungah; Lee, Impyeong
2015-01-01
We propose a novel approach to evaluating how effectively a closed circuit television (CCTV) system can monitor a targeted area. With 3D models of the target area and the camera parameters of the CCTV system, the approach produces surveillance coverage index, which is newly defined in this study as a quantitative measure for surveillance performance. This index indicates the proportion of the space being monitored with a sufficient resolution to the entire space of the target area. It is determined by computing surveillance resolution at every position and orientation, which indicates how closely a specific object can be monitored with a CCTV system. We present full mathematical derivation for the resolution, which depends on the location and orientation of the object as well as the geometric model of a camera. With the proposed approach, we quantitatively evaluated the surveillance coverage of a CCTV system in an underground parking area. Our evaluation process provided various quantitative-analysis results, compelling us to examine the design of the CCTV system prior to its installation and understand the surveillance capability of an existing CCTV system. PMID:26389909
Quantitative evaluation of 3D images produced from computer-generated holograms
NASA Astrophysics Data System (ADS)
Sheerin, David T.; Mason, Ian R.; Cameron, Colin D.; Payne, Douglas A.; Slinger, Christopher W.
1999-08-01
Advances in computing and optical modulation techniques now make it possible to anticipate the generation of near real- time, reconfigurable, high quality, three-dimensional images using holographic methods. Computer generated holography (CGH) is the only technique which holds promise of producing synthetic images having the full range of visual depth cues. These realistic images will be viewable by several users simultaneously, without the need for headtracking or special glasses. Such a data visualization tool will be key to speeding up the manufacture of new commercial and military equipment by negating the need for the production of physical 3D models in the design phase. DERA Malvern has been involved in designing and testing fixed CGH in order to understand the connection between the complexity of the CGH, the algorithms used to design them, the processes employed in their implementation and the quality of the images produced. This poster describes results from CGH containing up to 108 pixels. The methods used to evaluate the reconstructed images are discussed and quantitative measures of image fidelity made. An understanding of the effect of the various system parameters upon final image quality enables a study of the possible system trade-offs to be carried out. Such an understanding of CGH production and resulting image quality is key to effective implementation of a reconfigurable CGH system currently under development at DERA.
Resource theory of non-Gaussian operations
NASA Astrophysics Data System (ADS)
Zhuang, Quntao; Shor, Peter W.; Shapiro, Jeffrey H.
2018-05-01
Non-Gaussian states and operations are crucial for various continuous-variable quantum information processing tasks. To quantitatively understand non-Gaussianity beyond states, we establish a resource theory for non-Gaussian operations. In our framework, we consider Gaussian operations as free operations, and non-Gaussian operations as resources. We define entanglement-assisted non-Gaussianity generating power and show that it is a monotone that is nonincreasing under the set of free superoperations, i.e., concatenation and tensoring with Gaussian channels. For conditional unitary maps, this monotone can be analytically calculated. As examples, we show that the non-Gaussianity of ideal photon-number subtraction and photon-number addition equal the non-Gaussianity of the single-photon Fock state. Based on our non-Gaussianity monotone, we divide non-Gaussian operations into two classes: (i) the finite non-Gaussianity class, e.g., photon-number subtraction, photon-number addition, and all Gaussian-dilatable non-Gaussian channels; and (ii) the diverging non-Gaussianity class, e.g., the binary phase-shift channel and the Kerr nonlinearity. This classification also implies that not all non-Gaussian channels are exactly Gaussian dilatable. Our resource theory enables a quantitative characterization and a first classification of non-Gaussian operations, paving the way towards the full understanding of non-Gaussianity.
ERIC Educational Resources Information Center
Murtonen, Mari
2015-01-01
University research education in many disciplines is frequently confronted by problems with students' weak level of understanding of research concepts. A mind map technique was used to investigate how students understand central methodological concepts of empirical, theoretical, qualitative and quantitative. The main hypothesis was that some…
Mars Science Laboratory (MSL) : the US 2009 Mars rover mission
NASA Technical Reports Server (NTRS)
Palluconi, Frank; Tampari, Leslie; Steltzner, Adam; Umland, Jeff
2003-01-01
The Mars Science Laboratory mission is the 2009 United States Mars Exploration Program rover mission. The MSL Project expects to complete its pre-Phase A definition activity this fiscal year (FY2003), investigations in mid-March 2004, launch in 2009, arrive at Mars in 2010 during Northern hemisphere summer and then complete a full 687 day Mars year of surface exploration. MSL will assess the potential for habitability (past and present) of a carefully selected landing region on Mars by exploring for the chemical building blocks of life, and seeking to understand quantitatively the chemical and physical environment with which these components have interacted over the geologic history of the planet. Thus, MSL will advance substantially our understanding of the history of Mars and potentially, its capacity to sustain life.
Qualitative approaches to use of the RE-AIM framework: rationale and methods.
Holtrop, Jodi Summers; Rabin, Borsika A; Glasgow, Russell E
2018-03-13
There have been over 430 publications using the RE-AIM model for planning and evaluation of health programs and policies, as well as numerous applications of the model in grant proposals and national programs. Full use of the model includes use of qualitative methods to understand why and how results were obtained on different RE-AIM dimensions, however, recent reviews have revealed that qualitative methods have been used infrequently. Having quantitative and qualitative methods and results iteratively inform each other should enhance understanding and lessons learned. Because there have been few published examples of qualitative approaches and methods using RE-AIM for planning or assessment and no guidance on how qualitative approaches can inform these processes, we provide guidance on qualitative methods to address the RE-AIM model and its various dimensions. The intended audience is researchers interested in applying RE-AIM or similar implementation models, but the methods discussed should also be relevant to those in community or clinical settings. We present directions for, examples of, and guidance on how qualitative methods can be used to address each of the five RE-AIM dimensions. Formative qualitative methods can be helpful in planning interventions and designing for dissemination. Summative qualitative methods are useful when used in an iterative, mixed methods approach for understanding how and why different patterns of results occur. In summary, qualitative and mixed methods approaches to RE-AIM help understand complex situations and results, why and how outcomes were obtained, and contextual factors not easily assessed using quantitative measures.
NASA Astrophysics Data System (ADS)
Mayes, R.; Lyford, M. E.; Myers, J. D.
2009-12-01
The Quantitative Reasoning in STEM (QR STEM) project is a state level Mathematics and Science Partnership Project (MSP) with a focus on the mathematics and statistics that underlies the understanding of complex global scientific issues. This session is a companion session to the QR STEM: The Science presentation. The focus of this session is the quantitative reasoning aspects of the project. As students move from understandings that range from local to global in perspective on issues of energy and environment, there is a significant increase in the need for mathematical and statistical conceptual understanding. These understandings must be accessible to the students within the scientific context, requiring the special understandings that are endemic within quantitative reasoning. The QR STEM project brings together interdisciplinary teams of higher education faculty and middle/high school teachers to explore complex problems in energy and environment. The disciplines include life sciences, physics, chemistry, earth science, statistics, and mathematics. These interdisciplinary teams develop open ended performance tasks to implement in the classroom, based on scientific concepts that underpin energy and environment. Quantitative reasoning is broken down into three components: Quantitative Literacy, Quantitative Interpretation, and Quantitative Modeling. Quantitative Literacy is composed of arithmetic concepts such as proportional reasoning, numeracy, and descriptive statistics. Quantitative Interpretation includes algebraic and geometric concepts that underlie the ability to interpret a model of natural phenomena which is provided for the student. This model may be a table, graph, or equation from which the student is to make predictions or identify trends, or from which they would use statistics to explore correlations or patterns in data. Quantitative modeling is the ability to develop the model from data, including the ability to test hypothesis using statistical procedures. We use the term model very broadly, so it includes visual models such as box models, as well as best fit equation models and hypothesis testing. One of the powerful outcomes of the project is the conversation which takes place between science teachers and mathematics teachers. First they realize that though they are teaching concepts that cross their disciplines, the barrier of scientific language within their subjects restricts students from applying the concepts across subjects. Second the mathematics teachers discover the context of science as a means of providing real world situations that engage students in the utility of mathematics as a tool for solving problems. Third the science teachers discover the barrier to understanding science that is presented by poor quantitative reasoning ability. Finally the students are engaged in exploring energy and environment in a manner which exposes the importance of seeing a problem from multiple interdisciplinary perspectives. The outcome is a democratic citizen capable of making informed decisions, and perhaps a future scientist.
Goebel, Allison
2011-01-01
The waves of popular protest sweeping contemporary South Africa are inadequately explained by anti-globalisation, anti-neoliberal and even anti-government sentiments and analysis. Attention to the gendered dynamics of township life, including the nature of households, gender relations and the critical importance of social welfare provisions to poor women and their households, yields a revised understanding of protests and movements. The Durban-based shack-dwellers' movement Abahlali baseMjondolo is used to illustrate these points, as are original quantitative and qualitative data from urban townships in KwaZulu-Natal.
O'Connell, Thomas S; Bedford, K Juliet A; Thiede, Michael; McIntyre, Di
2015-06-09
A key element of the global drive to universal health coverage is ensuring access to needed health services for everyone, and to pursue this goal in an equitable way. This requires concerted efforts to reduce disparities in access through understanding and acting on barriers facing communities with the lowest utilisation levels. Financial barriers dominate the empirical literature on health service access. Unless the full range of access barriers are investigated, efforts to promote equitable access to health care are unlikely to succeed. This paper therefore focuses on exploring the nature and extent of non-financial access barriers. We draw upon two structured literature reviews on barriers to access and utilization of maternal, newborn and child health services in Ghana, Bangladesh, Vietnam and Rwanda. One review analyses access barriers identified in published literature using qualitative research methods; the other in published literature using quantitative analysis of household survey data. We then synthesised the key qualitative and quantitative findings through a conjoint iterative analysis. Five dominant themes on non-financial access barriers were identified: ethnicity; religion; physical accessibility; decision-making, gender and autonomy; and knowledge, information and education. The analysis highlighted that non-financial factors pose considerable barriers to access, many of which relate to the acceptability dimension of access and are challenging to address. Another key finding is that quantitative research methods, while yielding important findings, are inadequate for understanding non-financial access barriers in sufficient detail to develop effective responses. Qualitative research is critical in filling this gap. The analysis also indicates that the nature of non-financial access barriers vary considerably, not only between countries but also between different communities within individual countries. To adequately understand access barriers as a basis for developing effective strategies to address them, mixed-methods approaches are required. From an equity perspective, communities with the lowest utilisation levels should be prioritised and the access barriers specific to that community identified. It is, therefore, critical to develop approaches that can be used at the district level to diagnose and act upon access barriers if we are to pursue an equitable path to universal health coverage.
The Quantitative Preparation of Future Geoscience Graduate Students
NASA Astrophysics Data System (ADS)
Manduca, C. A.; Hancock, G. S.
2006-12-01
Modern geoscience is a highly quantitative science. In February, a small group of faculty and graduate students from across the country met to discuss the quantitative preparation of geoscience majors for graduate school. The group included ten faculty supervising graduate students in quantitative areas spanning the earth, atmosphere, and ocean sciences; five current graduate students in these areas; and five faculty teaching undergraduate students in the spectrum of institutions preparing students for graduate work. Discussion focused in four key ares: Are incoming graduate students adequately prepared for the quantitative aspects of graduate geoscience programs? What are the essential quantitative skills are that are required for success in graduate school? What are perceived as the important courses to prepare students for the quantitative aspects of graduate school? What programs/resources would be valuable in helping faculty/departments improve the quantitative preparation of students? The participants concluded that strengthening the quantitative preparation of undergraduate geoscience majors would increase their opportunities in graduate school. While specifics differed amongst disciplines, a special importance was placed on developing the ability to use quantitative skills to solve geoscience problems. This requires the ability to pose problems so they can be addressed quantitatively, understand the relationship between quantitative concepts and physical representations, visualize mathematics, test the reasonableness of quantitative results, creatively move forward from existing models/techniques/approaches, and move between quantitative and verbal descriptions. A list of important quantitative competencies desirable in incoming graduate students includes mechanical skills in basic mathematics, functions, multi-variate analysis, statistics and calculus, as well as skills in logical analysis and the ability to learn independently in quantitative ways. Calculus, calculus-based physics, chemistry, statistics, programming and linear algebra were viewed as important course preparation for a successful graduate experience. A set of recommendations for departments and for new community resources includes ideas for infusing quantitative reasoning throughout the undergraduate experience and mechanisms for learning from successful experiments in both geoscience and mathematics. A full list of participants, summaries of the meeting discussion and recommendations are available at http://serc.carleton.edu/quantskills/winter06/index.html. These documents, crafted by a small but diverse group can serve as a starting point for broader community discussion of the quantitative preparation of future geoscience graduate students.
Addison, Prue F E; Flander, Louisa B; Cook, Carly N
2017-08-01
Protected area management effectiveness (PAME) evaluation is increasingly undertaken to evaluate governance, assess conservation outcomes and inform evidence-based management of protected areas (PAs). Within PAME, quantitative approaches to assess biodiversity outcomes are now emerging, where biological monitoring data are directly assessed against quantitative (numerically defined) condition categories (termed quantitative condition assessments). However, more commonly qualitative condition assessments are employed in PAME, which use descriptive condition categories and are evaluated largely with expert judgement that can be subject to a range of biases, such as linguistic uncertainty and overconfidence. Despite the benefits of increased transparency and repeatability of evaluations, quantitative condition assessments are rarely used in PAME. To understand why, we interviewed practitioners from all Australian marine protected area (MPA) networks, which have access to long-term biological monitoring data and are developing or conducting PAME evaluations. Our research revealed that there is a desire within management agencies to implement quantitative condition assessment of biodiversity outcomes in Australian MPAs. However, practitioners report many challenges in transitioning from undertaking qualitative to quantitative condition assessments of biodiversity outcomes, which are hampering progress. Challenges include a lack of agency capacity (staff numbers and money), knowledge gaps, and diminishing public and political support for PAs. We point to opportunities to target strategies that will assist agencies overcome these challenges, including new decision support tools, approaches to better finance conservation efforts, and to promote more management relevant science. While a single solution is unlikely to achieve full evidence-based conservation, we suggest ways for agencies to target strategies and advance PAME evaluations toward best practice. Copyright © 2017 Elsevier Ltd. All rights reserved.
Biokinetics of zinc oxide nanoparticles: toxicokinetics, biological fates, and protein interaction
Choi, Soo-Jin; Choy, Jin-Ho
2014-01-01
Biokinetic studies of zinc oxide (ZnO) nanoparticles involve systematic and quantitative analyses of absorption, distribution, metabolism, and excretion in plasma and tissues of whole animals after exposure. A full understanding of the biokinetics provides basic information about nanoparticle entry into systemic circulation, target organs of accumulation and toxicity, and elimination time, which is important for predicting the long-term toxic potential of nanoparticles. Biokinetic behaviors can be dependent on physicochemical properties, dissolution property in biological fluids, and nanoparticle–protein interaction. Moreover, the determination of biological fates of ZnO nanoparticles in the systemic circulation and tissues is critical in interpreting biokinetic behaviors and predicting toxicity potential as well as mechanism. This review focuses on physicochemical factors affecting the biokinetics of ZnO nanoparticles, in concert with understanding bioavailable fates and their interaction with proteins. PMID:25565844
Roberts, David W; Patlewicz, Grace; Kern, Petra S; Gerberick, Frank; Kimber, Ian; Dearman, Rebecca J; Ryan, Cindy A; Basketter, David A; Aptula, Aynur O
2007-07-01
The goal of eliminating animal testing in the predictive identification of chemicals with the intrinsic ability to cause skin sensitization is an important target, the attainment of which has recently been brought into even sharper relief by the EU Cosmetics Directive and the requirements of the REACH legislation. Development of alternative methods requires that the chemicals used to evaluate and validate novel approaches comprise not only confirmed skin sensitizers and non-sensitizers but also substances that span the full chemical mechanistic spectrum associated with skin sensitization. To this end, a recently published database of more than 200 chemicals tested in the mouse local lymph node assay (LLNA) has been examined in relation to various chemical reaction mechanistic domains known to be associated with sensitization. It is demonstrated here that the dataset does cover the main reaction mechanistic domains. In addition, it is shown that assignment to a reaction mechanistic domain is a critical first step in a strategic approach to understanding, ultimately on a quantitative basis, how chemical properties influence the potency of skin sensitizing chemicals. This understanding is necessary if reliable non-animal approaches, including (quantitative) structure-activity relationships (Q)SARs, read-across, and experimental chemistry based models, are to be developed.
Statistical genetics and evolution of quantitative traits
NASA Astrophysics Data System (ADS)
Neher, Richard A.; Shraiman, Boris I.
2011-10-01
The distribution and heritability of many traits depends on numerous loci in the genome. In general, the astronomical number of possible genotypes makes the system with large numbers of loci difficult to describe. Multilocus evolution, however, greatly simplifies in the limit of weak selection and frequent recombination. In this limit, populations rapidly reach quasilinkage equilibrium (QLE) in which the dynamics of the full genotype distribution, including correlations between alleles at different loci, can be parametrized by the allele frequencies. This review provides a simplified exposition of the concept and mathematics of QLE which is central to the statistical description of genotypes in sexual populations. Key results of quantitative genetics such as the generalized Fisher’s “fundamental theorem,” along with Wright’s adaptive landscape, are shown to emerge within QLE from the dynamics of the genotype distribution. This is followed by a discussion under what circumstances QLE is applicable, and what the breakdown of QLE implies for the population structure and the dynamics of selection. Understanding the fundamental aspects of multilocus evolution obtained through simplified models may be helpful in providing conceptual and computational tools to address the challenges arising in the studies of complex quantitative phenotypes of practical interest.
Federal Register 2010, 2011, 2012, 2013, 2014
2010-03-22
...-depth understanding of individuals' attitudes, beliefs, motivations, and feelings than do quantitative... and as a qualitative research tool have three major purposes: To obtain information that is useful for developing variables and measures for quantitative studies, To better understand people's attitudes and...
The Solar Dynamics Observatory
NASA Technical Reports Server (NTRS)
Pesnell, William D.
2008-01-01
The Solar Dynamics Observatory (SDO) is the first Space Weather Mission in NASA's Living With a Star Program. SDO's main goal is to understand, driving towards a predictive capability, those solar variations that influence life on Earth and humanity's technological systems. The past decade has seen an increasing emphasis on understanding the entire Sun, from the nuclear reactions at the core to the development and loss of magnetic loops in the corona. SDO's three science investigations (HMI, AIA, and EVE) will determine how the Sun's magnetic field is generated and structured, how this stored magnetic energy is released into the heliosphere and geospace as the solar wind, energetic particles, and variations in the solar irradiance. SDO will return full-disk Dopplergrams, full-disk vector magnetograms, full-disk images at nine EIUV wavelengths, and EUV spectral irradiances, all taken at a rapid cadence. This means you can 'observe the database' to study events, but we can also move forward in producing quantitative models of what the Sun is doing today. SDO is scheduled to launch in 2008 on an Atlas V rocket from the Kennedy Space Center, Cape Canaveral, Florida. The satellite will fly in a 28 degree inclined geosynchronous orbit about the longitude of New Mexico, where a dedicated Ka-band ground station will receive the 150 Mbps data flow. How SDO data will transform the study of the Sun and its affect on Space Weather studies will be discussed.
Estimation of masonry mechanical characteristics by ESPI fringe interpretation
NASA Astrophysics Data System (ADS)
Facchini, M.; Zanetta, P.; Binda, L.; Roberti, G. Mirabella; Tiraboschi, C.
Electronic speckle pattern interferometry (ESPI) can be a powerful tool for efficient non-destructive testing and evaluation of micro-deformations of masonry materials and structures. Unlike traditional transducers, ESPI requires no direct contact with the object, and the full-field visualisation it offers provides for a better understanding of the surface behaviour. This paper describes an in-plane deformation inspection system which has been built up for an automatic acquisition of interferograms at different stages of a test. The system is applied to the evaluation of some mechanical characteristics of masonry components. Qualitative and quantitative results are obtained and an overall discussion is presented.
Modeling inelastic phonon scattering in atomic- and molecular-wire junctions
NASA Astrophysics Data System (ADS)
Paulsson, Magnus; Frederiksen, Thomas; Brandbyge, Mads
2005-11-01
Computationally inexpensive approximations describing electron-phonon scattering in molecular-scale conductors are derived from the nonequilibrium Green’s function method. The accuracy is demonstrated with a first-principles calculation on an atomic gold wire. Quantitative agreement between the full nonequilibrium Green’s function calculation and the newly derived expressions is obtained while simplifying the computational burden by several orders of magnitude. In addition, analytical models provide intuitive understanding of the conductance including nonequilibrium heating and provide a convenient way of parameterizing the physics. This is exemplified by fitting the expressions to the experimentally observed conductances through both an atomic gold wire and a hydrogen molecule.
Simulation of FRET dyes allows quantitative comparison against experimental data
NASA Astrophysics Data System (ADS)
Reinartz, Ines; Sinner, Claude; Nettels, Daniel; Stucki-Buchli, Brigitte; Stockmar, Florian; Panek, Pawel T.; Jacob, Christoph R.; Nienhaus, Gerd Ulrich; Schuler, Benjamin; Schug, Alexander
2018-03-01
Fully understanding biomolecular function requires detailed insight into the systems' structural dynamics. Powerful experimental techniques such as single molecule Förster Resonance Energy Transfer (FRET) provide access to such dynamic information yet have to be carefully interpreted. Molecular simulations can complement these experiments but typically face limits in accessing slow time scales and large or unstructured systems. Here, we introduce a coarse-grained simulation technique that tackles these challenges. While requiring only few parameters, we maintain full protein flexibility and include all heavy atoms of proteins, linkers, and dyes. We are able to sufficiently reduce computational demands to simulate large or heterogeneous structural dynamics and ensembles on slow time scales found in, e.g., protein folding. The simulations allow for calculating FRET efficiencies which quantitatively agree with experimentally determined values. By providing atomically resolved trajectories, this work supports the planning and microscopic interpretation of experiments. Overall, these results highlight how simulations and experiments can complement each other leading to new insights into biomolecular dynamics and function.
Quantitative theory of hydrophobic effect as a driving force of protein structure
Perunov, Nikolay; England, Jeremy L
2014-01-01
Various studies suggest that the hydrophobic effect plays a major role in driving the folding of proteins. In the past, however, it has been challenging to translate this understanding into a predictive, quantitative theory of how the full pattern of sequence hydrophobicity in a protein shapes functionally important features of its tertiary structure. Here, we extend and apply such a phenomenological theory of the sequence-structure relationship in globular protein domains, which had previously been applied to the study of allosteric motion. In an effort to optimize parameters for the model, we first analyze the patterns of backbone burial found in single-domain crystal structures, and discover that classic hydrophobicity scales derived from bulk physicochemical properties of amino acids are already nearly optimal for prediction of burial using the model. Subsequently, we apply the model to studying structural fluctuations in proteins and establish a means of identifying ligand-binding and protein–protein interaction sites using this approach. PMID:24408023
Quantitative Methods in Psychology: Inevitable and Useless
Toomela, Aaro
2010-01-01
Science begins with the question, what do I want to know? Science becomes science, however, only when this question is justified and the appropriate methodology is chosen for answering the research question. Research question should precede the other questions; methods should be chosen according to the research question and not vice versa. Modern quantitative psychology has accepted method as primary; research questions are adjusted to the methods. For understanding thinking in modern quantitative psychology, two epistemologies should be distinguished: structural-systemic that is based on Aristotelian thinking, and associative-quantitative that is based on Cartesian–Humean thinking. The first aims at understanding the structure that underlies the studied processes; the second looks for identification of cause–effect relationships between the events with no possible access to the understanding of the structures that underlie the processes. Quantitative methodology in particular as well as mathematical psychology in general, is useless for answering questions about structures and processes that underlie observed behaviors. Nevertheless, quantitative science is almost inevitable in a situation where the systemic-structural basis of behavior is not well understood; all sorts of applied decisions can be made on the basis of quantitative studies. In order to proceed, psychology should study structures; methodologically, constructive experiments should be added to observations and analytic experiments. PMID:21833199
Quantitative methods in psychology: inevitable and useless.
Toomela, Aaro
2010-01-01
Science begins with the question, what do I want to know? Science becomes science, however, only when this question is justified and the appropriate methodology is chosen for answering the research question. Research question should precede the other questions; methods should be chosen according to the research question and not vice versa. Modern quantitative psychology has accepted method as primary; research questions are adjusted to the methods. For understanding thinking in modern quantitative psychology, two epistemologies should be distinguished: structural-systemic that is based on Aristotelian thinking, and associative-quantitative that is based on Cartesian-Humean thinking. The first aims at understanding the structure that underlies the studied processes; the second looks for identification of cause-effect relationships between the events with no possible access to the understanding of the structures that underlie the processes. Quantitative methodology in particular as well as mathematical psychology in general, is useless for answering questions about structures and processes that underlie observed behaviors. Nevertheless, quantitative science is almost inevitable in a situation where the systemic-structural basis of behavior is not well understood; all sorts of applied decisions can be made on the basis of quantitative studies. In order to proceed, psychology should study structures; methodologically, constructive experiments should be added to observations and analytic experiments.
Roberts, Lynne D.; Castell, Emily
2016-01-01
In Australia the tradition of conducting quantitative psychological research within a positivist framework has been challenged, with calls made for the inclusion of the full range of qualitative and quantitative methodologies within the undergraduate psychology curriculum. Despite this, the undergraduate psychology curriculum in most Australian universities retains a strong focus on teaching quantitative research methods. Limited research has examined attitudes toward qualitative research held by undergraduate psychology students taught within a positivist framework, and whether these attitudes are malleable and can be changed through teaching qualitative methodologies. Previous research has suggested that students from strong quantitative backgrounds experience some cognitive dissonance and greater difficulties in learning qualitative methods. In this article we examine 3rd year undergraduate psychology students’ attitudes to qualitative research prior to commencing and upon completion of a qualitative research unit. All students had previously completed two 13 weeks units of study in quantitative research methods. At Time 1, 63 students (84.1% female) completed online surveys comprising attitudinal measures. Key themes to emerge from student comments were that qualitative research was seen as an alternative approach, representing a paradigmatic shift that was construed by some students advantageous for meeting future professional and educative goals. Quantitative measures of attitudes to qualitative research were associated with general attitudes toward research, and psychology-specific epistemological beliefs. Changes in attitudes following completion of the qualitative research methods unit were in the hypothesized direction, but non-significant (small effect sizes). The findings increase our understanding of psychology students’ attitudes toward qualitative research and inform our recommendations for teaching research methods within the undergraduate psychology curriculum. PMID:27242602
Roberts, Lynne D; Castell, Emily
2016-01-01
In Australia the tradition of conducting quantitative psychological research within a positivist framework has been challenged, with calls made for the inclusion of the full range of qualitative and quantitative methodologies within the undergraduate psychology curriculum. Despite this, the undergraduate psychology curriculum in most Australian universities retains a strong focus on teaching quantitative research methods. Limited research has examined attitudes toward qualitative research held by undergraduate psychology students taught within a positivist framework, and whether these attitudes are malleable and can be changed through teaching qualitative methodologies. Previous research has suggested that students from strong quantitative backgrounds experience some cognitive dissonance and greater difficulties in learning qualitative methods. In this article we examine 3rd year undergraduate psychology students' attitudes to qualitative research prior to commencing and upon completion of a qualitative research unit. All students had previously completed two 13 weeks units of study in quantitative research methods. At Time 1, 63 students (84.1% female) completed online surveys comprising attitudinal measures. Key themes to emerge from student comments were that qualitative research was seen as an alternative approach, representing a paradigmatic shift that was construed by some students advantageous for meeting future professional and educative goals. Quantitative measures of attitudes to qualitative research were associated with general attitudes toward research, and psychology-specific epistemological beliefs. Changes in attitudes following completion of the qualitative research methods unit were in the hypothesized direction, but non-significant (small effect sizes). The findings increase our understanding of psychology students' attitudes toward qualitative research and inform our recommendations for teaching research methods within the undergraduate psychology curriculum.
Subscale Test Program for the Orion Conical Ribbon Drogue Parachute
NASA Technical Reports Server (NTRS)
Sengupta, Anita; Stuart, Phil; Machin, Ricardo; Bourland, Gary; Schwing, Allen; Longmire, Ellen; Henning, Elsa; Sinclair, Rob
2011-01-01
A subscale wind tunnel test program for Orion's conical ribbon drogue parachute is under development. The desired goals of the program are to quantify aerodynamic performance of the parachute in the wake of the entry vehicle, including understanding of the coupling of the parachute and command module dynamics, and an improved understanding of the load distribution within the textile elements of the parachute. The test program is ten percent of full scale conducted in a 3x2.1 m (10x7 ft) closed loop subsonic wind tunnel. The subscale test program is uniquely suited to probing the aerodynamic and structural environment in both a quantitative and qualitative manner. Non-intrusive diagnostics, including Particle Image Velocimetry for wake velocity surveys, high speed pressure transducers for canopy pressure distribution, and a high speed photogrammetric reconstruction, will be used to quantify the parachute's performance.
ERIC Educational Resources Information Center
Luyt, Russell
2012-01-01
A framework for quantitative measurement development, validation, and revision that incorporates both qualitative and quantitative methods is introduced. It extends and adapts Adcock and Collier's work, and thus, facilitates understanding of quantitative measurement development, validation, and revision as an integrated and cyclical set of…
Clough, Dagmar; Råberg, Lars
2014-12-01
Host specificity is a fundamental property of parasites. Whereas most studies focus on measures of specificity on host range, only few studies have considered quantitative aspects such as infection intensity or prevalence. The relative importance of these quantitative aspects is still unclear, mainly because of methodological constraints, yet central to a precise assessment of host specificity. Here, we assessed simultaneously two quantitative measures of host specificity of Heligmosomoides glareoli and Heligmosomoides polygyrus polygyrus infections in sympatric rodent hosts. We used standard morphological techniques as well as real-time quantitative PCR and sequencing of the rDNA ITS2 fragment to analyse parasite infection via faecal sample remains. Although both parasite species are thought to be strictly species-specific, we found morphologically and molecularly validated co- and cross-infections. We also detected contrasting patterns within and between host species with regard to specificity for prevalence and intensity of infection. H. glareoli intensities were twofold higher in bank voles than in yellow-necked mice, but prevalence did not differ significantly between species (33 vs. 18%). We found the opposite pattern in H. polygyrus infections with similar intensity levels between host species but significantly higher prevalence in mouse hosts (56 vs. 10%). Detection rates were higher with molecular tools than morphological methods. Our results emphasize the necessity to consider quantitative aspects of specificity for a full view of a parasites' capacity to replicate and transmit in hosts and present a worked example of how modern molecular tools help to advance our understanding of selective forces in host-parasite ecology and evolution.
Understanding Quantitative and Qualitative Research in Early Childhood Education.
ERIC Educational Resources Information Center
Goodwin, William L.; Goodwin, Laura D.
This book describes the research process in order to facilitate understanding of the process and its products, especially as they pertain to early childhood education. It examines both quantitative and qualitative research methods, emphasizing ways in which they can be used together to fully study a given phenomenon or topic. Chapter 1 examines…
ERIC Educational Resources Information Center
Haque, Mohammad Mahfujul; Little, David C.; Barman, Benoy K.; Wahab, Md. Abdul
2010-01-01
Purpose: The purpose of the study was to understand the adoption process of ricefield based fish seed production (RBFSP) that has been developed, promoted and established in Northwest Bangladesh. Design/Methodology/Approach: Quantitative investigation based on regression analysis and qualitative investigation using semi-structured interview were…
Writing for Understanding: The Effect of Using Informational Writing on Student Science Achievement
ERIC Educational Resources Information Center
Parson, Atiya
2013-01-01
The purpose of this quantitative study was to investigate whether or not informational writing in the science curriculum would impact fifth grade students' science achievement and conceptual understanding. The population of this study came from a metropolitan school district in the state of Georgia for school year 2012-2013. The quantitative data…
Validating multiplexes for use in conjunction with modern interpretation strategies.
Taylor, Duncan; Bright, Jo-Anne; McGoven, Catherine; Hefford, Christopher; Kalafut, Tim; Buckleton, John
2016-01-01
In response to requests from the forensic community, commercial companies are generating larger, more sensitive, and more discriminating STR multiplexes. These multiplexes are now applied to a wider range of samples including complex multi-person mixtures. In parallel there is an overdue reappraisal of profile interpretation methodology. Aspects of this reappraisal include 1. The need for a quantitative understanding of allele and stutter peak heights and their variability, 2. An interest in reassessing the utility of smaller peaks below the often used analytical threshold, 3. A need to understand not just the occurrence of peak drop-in but also the height distribution of such peaks, and 4. A need to understand the limitations of the multiplex-interpretation strategy pair implemented. In this work we present a full scheme for validation of a new multiplex that is suitable for informing modern interpretation practice. We predominantly use GlobalFiler™ as an example multiplex but we suggest that the aspects investigated here are fundamental to introducing any multiplex in the modern interpretation environment. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.
Ley, P
1985-04-01
Patients frequently fail to understand what they are told. Further, they frequently forget the information given to them. These factors have effects on patients' satisfaction with the consultation. All three of these factors--understanding, memory and satisfaction--have effects on the probability that a patient will comply with advice. The levels of failure to understand and remember and levels of dissatisfaction are described. Quantitative estimates of the effects of these factors on non-compliance are presented.
NASA Astrophysics Data System (ADS)
Li, Chunhui; Guan, Guangying; Huang, Zhihong; Wang, Ruikang K.; Nabi, Ghulam
2015-03-01
By combining with the phase sensitive optical coherence tomography (PhS-OCT), vibration and surface acoustic wave (SAW) methods have been reported to provide elastography of skin tissue respectively. However, neither of these two methods can provide the elastography in full skin depth in current systems. This paper presents a feasibility study on an optical coherence elastography method which combines both vibration and SAW in order to give the quantitative mechanical properties of skin tissue with full depth range, including epidermis, dermis and subcutaneous fat. Experiments are carried out on layered tissue mimicking phantoms and in vivo human forearm and palm skin. A ring actuator generates vibration while a line actuator were used to excited SAWs. A PhS-OCT system is employed to provide the ultrahigh sensitive measurement of the generated waves. The experimental results demonstrate that by the combination of vibration and SAW method the full skin bulk mechanical properties can be quantitatively measured and further the elastography can be obtained with a sensing depth from ~0mm to ~4mm. This method is promising to apply in clinics where the quantitative elasticity of localized skin diseases is needed to aid the diagnosis and treatment.
Effects of the local structure dependence of evaporation fields on field evaporation behavior
DOE Office of Scientific and Technical Information (OSTI.GOV)
Yao, Lan; Marquis, Emmanuelle A., E-mail: emarq@umich.edu; Withrow, Travis
2015-12-14
Accurate three dimensional reconstructions of atomic positions and full quantification of the information contained in atom probe microscopy data rely on understanding the physical processes taking place during field evaporation of atoms from needle-shaped specimens. However, the modeling framework for atom probe microscopy has only limited quantitative justification. Building on the continuum field models previously developed, we introduce a more physical approach with the selection of evaporation events based on density functional theory calculations. This model reproduces key features observed experimentally in terms of sequence of evaporation, evaporation maps, and depth resolution, and provides insights into the physical limit formore » spatial resolution.« less
The Solar Dynamics Observatory: Your Eye On The Sun
NASA Technical Reports Server (NTRS)
Pesnell, William Dean
2008-01-01
The Sun hiccups and satellites die. That is what NASA's Living With a Star Program is all about. The Solar Dynamics Observatory (SDO) is the first Space Weather Mission in LWS. SDO's main goal is to understand, driving towards a predictive capability, those solar variations that influence life on Earth and humanity's technological systems. The past decade has seen an increasing emphasis on understanding the entire Sun, from the nuclear reactions at the core to the development and loss of magnetic loops in the corona. SDO's three science investigations (HMI, AIA, and EVE) will determine how the Sun's magnetic field is generated and structured, how this stored magnetic energy is released into the heliosphere and geospace as the solar wind, energetic particles, and variations in the solar irradiance. SDO will return full-disk Dopplergrams, full-disk vector magnetograms, full-disk images at nine E/UV wavelengths, and EUV spectral irradiances, all taken at a rapid cadence. This means you can "observe the database" to study events, but we can also move forward in producing quantitative models of what the Sun is doing today. SDO is scheduled to launch in 2008 on an Atlas V rocket from the Kennedy Space Center, Cape Canaveral, Florida. The satellite will fly in a 28 degree inclined geosynchronous orbit about the longitude of New Mexico, where a dedicated Ka-band ground station will receive the 150 Mbps data flow. How SDO data will transform the study of the Sun and its affect on Space Weather studies will be discussed.
Hakkaart, Xavier D V; Pronk, Jack T; van Maris, Antonius J A
2017-01-01
Understanding microbial growth and metabolism is a key learning objective of microbiology and biotechnology courses, essential for understanding microbial ecology, microbial biotechnology and medical microbiology. Chemostat cultivation, a key research tool in microbial physiology that enables quantitative analysis of growth and metabolism under tightly defined conditions, provides a powerful platform to teach key features of microbial growth and metabolism. Substrate-limited chemostat cultivation can be mathematically described by four equations. These encompass mass balances for biomass and substrate, an empirical relation that describes distribution of consumed substrate over growth and maintenance energy requirements (Pirt equation), and a Monod-type equation that describes the relation between substrate concentration and substrate-consumption rate. The authors felt that the abstract nature of these mathematical equations and a lack of visualization contributed to a suboptimal operative understanding of quantitative microbial physiology among students who followed their Microbial Physiology B.Sc. courses. The studio-classroom workshop presented here was developed to improve student understanding of quantitative physiology by a set of question-guided simulations. Simulations are run on Chemostatus, a specially developed MATLAB-based program, which visualizes key parameters of simulated chemostat cultures as they proceed from dynamic growth conditions to steady state. In practice, the workshop stimulated active discussion between students and with their teachers. Moreover, its introduction coincided with increased average exam scores for questions on quantitative microbial physiology. The workshop can be easily implemented in formal microbial physiology courses or used by individuals seeking to test and improve their understanding of quantitative microbial physiology and/or chemostat cultivation.
ERIC Educational Resources Information Center
Burdett, Kimberli R.
2013-01-01
The purpose of this study was to gain a better understanding of how current internet-based resources are affecting the college choice process. An explanatory mixed methods design was used, and the study involved collecting qualitative data after a quantitative phase to explain the quantitative data in greater depth. An additional study was…
An Exploratory Analysis of the Navy Personnel Support Delivery Model
2017-09-01
technology-competent generation. Our efforts are focused on providing a quantitative effort to understanding past trends in Personnel Support Detachment (PSD... quantitative effort to understanding past trends in Personnel Support Detachment (PSD) and Customer Service Desk (CSD) transactions that may aid manpower...56 xiv THIS PAGE INTENTIONALLY LEFT BLANK xv LIST OF TABLES Table 1. Final Dataset Column Names and Descriptions
Khan, Munawwar A.; Patel, Poojabahen G.; Ganesh, Arpitha G.; Rais, Naushad; Faheem, Sultan M.; Khan, Shams T.
2018-01-01
Introduction: Anaerobic digestion for methane production comprises of an exceptionally diverse microbial consortium, a profound understanding about which is still constrained. In this study, the methanogenic archaeal communities in three full-scale anaerobic digesters of a Municipal Wastewater Treatment Plant were analyzed by Fluorescence in situ hybridization and quantitative real-time Polymerase Chain Reaction (qPCR) technique. Methods & Materials: Fluorescence in situ hybridization (FISH) was performed to detect and quantify the methanogenic Archaea in the sludge samples whereas qPCR was carried out to support the FISH analysis. Multiple probes targeting domain archaea, different orders and families of Archaea were used for the studies. Results and Discussion: In general, the aceticlastic organisms (Methanosarcinaceae & Methanosaetaceae) were more abundant than the hydrogenotrophic organisms (Methanobacteriales, Methanomicrobiales, Methanobacteriaceae & Methanococcales). Both FISH and qPCR indicated that family Methanosaetaceae was the most abundant suggesting that aceticlastic methanogenesis is probably the dominant methane production pathway in these digesters. Conclusion: Future work involving high-throughput sequencing methods and correlating archaeal communities with the main operational parameters of anaerobic digesters will help to obtain a better understanding of the dynamics of the methanogenic archaeal community in wastewater treatment plants in United Arab Emirates (UAE) which in turn would lead to improved performance of anaerobic sludge digesters. PMID:29785219
USDA-ARS?s Scientific Manuscript database
Classical quantitative genetics aids crop improvement by providing the means to estimate heritability, genetic correlations, and predicted responses to various selection schemes. Genomics has the potential to aid quantitative genetics and applied crop improvement programs via large-scale, high-thro...
Longo, Christopher J; Fitch, Margaret; Grignon, Michel; McAndrew, Alison
2016-11-01
This research informs existing work by examining the full scope of out-of-pocket costs and lost income, patients' private insurance behaviors, and their overall management of finances during their cancer treatment. The intent was to gain a deeper understanding of patient circumstances and the related costs. Participant qualitative interviews were conducted in person during outpatient clinic visits or by telephone and were recorded between June 2011 and July 2012. Interviews were transcribed verbatim and subjected to a descriptive qualitative analysis. The research team collaborated early in the process (after three subjects were enrolled) to develop a preliminary coding framework. The coding framework was modified to incorporate additional emerging content until saturation of data was evident. Transcripts were coded using the qualitative software NVivo version 9.0. Fifteen patients agreed to participate in the study and 14 completed the interview (seven breast, three colorectal, two lung, and two prostate). Consistent with existing published work, participants expressed concerns regarding expenses related to medications, complementary/alternative medicines, devices, parking and travel. These concerns were exacerbated if patients did not have insurance or lost insurance coverage due to loss of work. Although many acknowledged in hindsight that additional insurance would have helped, they also recognized that at the time of their diagnoses, it was not a viable option. Previously unidentified categorical costs identified in this study included modifications to housing arrangements or renovations, special clothing, fitness costs and the impact of an altered diet. We confirmed the results of earlier Canadian quantitative work. Additionally, cost categories not previously explored were identified, which will facilitate the development of an improved and more comprehensive quantitative questionnaire for future research. Many patients indicated that supplemental health insurance would have made their cancer journey less stressful, highlighting existing gaps in the government funded health care system.
Nelson, Geoffrey; Macnaughton, Eric; Goering, Paula
2015-11-01
Using the case of a large-scale, multi-site Canadian Housing First research demonstration project for homeless people with mental illness, At Home/Chez Soi, we illustrate the value of qualitative methods in a randomized controlled trial (RCT) of a complex community intervention. We argue that quantitative RCT research can neither capture the complexity nor tell the full story of a complex community intervention. We conceptualize complex community interventions as having multiple phases and dimensions that require both RCT and qualitative research components. Rather than assume that qualitative research and RCTs are incommensurate, a more pragmatic mixed methods approach was used, which included using both qualitative and quantitative methods to understand program implementation and outcomes. At the same time, qualitative research was used to examine aspects of the intervention that could not be understood through the RCT, such as its conception, planning, sustainability, and policy impacts. Through this example, we show how qualitative research can tell a more complete story about complex community interventions. Copyright © 2015 Elsevier Inc. All rights reserved.
Measuring Quantum Coherence with Entanglement.
Streltsov, Alexander; Singh, Uttam; Dhar, Himadri Shekhar; Bera, Manabendra Nath; Adesso, Gerardo
2015-07-10
Quantum coherence is an essential ingredient in quantum information processing and plays a central role in emergent fields such as nanoscale thermodynamics and quantum biology. However, our understanding and quantitative characterization of coherence as an operational resource are still very limited. Here we show that any degree of coherence with respect to some reference basis can be converted to entanglement via incoherent operations. This finding allows us to define a novel general class of measures of coherence for a quantum system of arbitrary dimension, in terms of the maximum bipartite entanglement that can be generated via incoherent operations applied to the system and an incoherent ancilla. The resulting measures are proven to be valid coherence monotones satisfying all the requirements dictated by the resource theory of quantum coherence. We demonstrate the usefulness of our approach by proving that the fidelity-based geometric measure of coherence is a full convex coherence monotone, and deriving a closed formula for it on arbitrary single-qubit states. Our work provides a clear quantitative and operational connection between coherence and entanglement, two landmark manifestations of quantum theory and both key enablers for quantum technologies.
Jet measurements in heavy ion physics
NASA Astrophysics Data System (ADS)
Connors, Megan; Nattrass, Christine; Reed, Rosi; Salur, Sevil
2018-04-01
A hot, dense medium called a quark gluon plasma (QGP) is created in ultrarelativistic heavy ion collisions. Early in the collision, hard parton scatterings generate high momentum partons that traverse the medium, which then fragment into sprays of particles called jets. Understanding how these partons interact with the QGP and fragment into final state particles provides critical insight into quantum chromodynamics. Experimental measurements from high momentum hadrons, two particle correlations, and full jet reconstruction at the Relativistic Heavy Ion Collider (RHIC) and the Large Hadron Collider (LHC) continue to improve our understanding of energy loss in the QGP. Run 2 at the LHC recently began and there is a jet detector at RHIC under development. Now is the perfect time to reflect on what the experimental measurements have taught us so far, the limitations of the techniques used for studying jets, how the techniques can be improved, and how to move forward with the wealth of experimental data such that a complete description of energy loss in the QGP can be achieved. Measurements of jets to date clearly indicate that hard partons lose energy. Detailed comparisons of the nuclear modification factor between data and model calculations led to quantitative constraints on the opacity of the medium to hard probes. However, while there is substantial evidence for softening and broadening jets through medium interactions, the difficulties comparing measurements to theoretical calculations limit further quantitative constraints on energy loss mechanisms. Since jets are algorithmic descriptions of the initial parton, the same jet definitions must be used, including the treatment of the underlying heavy ion background, when making data and theory comparisons. An agreement is called for between theorists and experimentalists on the appropriate treatment of the background, Monte Carlo generators that enable experimental algorithms to be applied to theoretical calculations, and a clear understanding of which observables are most sensitive to the properties of the medium, even in the presence of background. This will enable us to determine the best strategy for the field to improve quantitative constraints on properties of the medium in the face of these challenges.
ERIC Educational Resources Information Center
Marrus, Natasha; Faughn, Carley; Shuman, Jeremy; Petersen, Steve E.; Constantino, John N.; Povinelli, Daniel J.; Pruett, John R., Jr.
2011-01-01
Objective: Comparative studies of social responsiveness, an ability that is impaired in autism spectrum disorders, can inform our understanding of both autism and the cognitive architecture of social behavior. Because there is no existing quantitative measure of social responsiveness in chimpanzees, we generated a quantitative, cross-species…
Development and Measurement of Preschoolers' Quantitative Knowledge
ERIC Educational Resources Information Center
Geary, David C.
2015-01-01
The collection of studies in this special issue make an important contribution to our understanding and measurement of the core cognitive and noncognitive factors that influence children's emerging quantitative competencies. The studies also illustrate how the field has matured, from a time when the quantitative competencies of infants and young…
Brewster, Zachary W; Rusche, Sarah Nell
2012-01-01
Despite popular claims that racism and discrimination are no longer salient issues in contemporary society, members of racially underrepresented groups continue to experience disparate treatment in everyday public interactions. The context of full-service restaurants is one such public setting wherein African Americans, in particular, encounter racial prejudices and discriminatory treatment. To further understand the pervasiveness of such anti-Black attitudes and actions within the restaurant context, this article analyzes primary survey data derived from a community sample of servers (N = 200). Participants were asked a series of questions ascertaining information about the racial climate of their workplaces. Findings reveal substantial server negativity toward African Americans' tipping and dining behaviors. Racialized discourse and discriminatory behaviors are also shown to be quite common in the restaurant context. The anti-Black attitudes and actions that the authors document in this research are illustrative of the continuing significance of race in contemporary society, and the authors encourage further research on this relatively neglected area of inquiry.
Generation time, life history and the substitution rate of neutral mutations.
Lehtonen, Jussi; Lanfear, Robert
2014-11-01
Our understanding of molecular evolution is hampered by a lack of quantitative predictions about how life-history (LH) traits should correlate with substitution rates. Comparative studies have shown that neutral substitution rates vary substantially between species, and evidence shows that much of this diversity is associated with variation in LH traits. However, while these studies often agree, some unexplained and contradictory results have emerged. Explaining these results is difficult without a clear theoretical understanding of the problem. In this study, we derive predictions for the relationships between LH traits and substitution rates in iteroparous species by using demographic theory to relate commonly measured life-history traits to genetic generation time, and by implication to neutral substitution rates. This provides some surprisingly simple explanations for otherwise confusing patterns, such as the association between fecundity and substitution rates. The same framework can be applied to more complex life histories if full life-tables are available. © 2014 The Author(s) Published by the Royal Society. All rights reserved.
Brewster, Zachary W
2012-01-01
Despite popular claims that racism and discrimination are no longer salient issues in contemporary society, racial minorities continue to experience disparate treatment in everyday public interactions. The context of full-service restaurants is one such public setting wherein racial minority patrons, African Americans in particular, encounter racial prejudices and discriminate treatment. To further understand the causes of such discriminate treatment within the restaurant context, this article analyzes primary survey data derived from a community sample of servers (N = 200) to assess the explanatory power of one posited explanation—statistical discrimination. Taken as a whole, findings suggest that while a statistical discrimination framework toward understanding variability in servers’ discriminatory behaviors should not be disregarded, the framework’s explanatory utility is limited. Servers’ inferences about the potential profitability of waiting on customers across racial groups explain little of the overall variation in subjects’ self-reported discriminatory behaviors, thus suggesting that other factors not explored in this research are clearly operating and should be the focus of future inquires.
GAO, L.; HAGEN, N.; TKACZYK, T.S.
2012-01-01
Summary We implement a filterless illumination scheme on a hyperspectral fluorescence microscope to achieve full-range spectral imaging. The microscope employs polarisation filtering, spatial filtering and spectral unmixing filtering to replace the role of traditional filters. Quantitative comparisons between full-spectrum and filter-based microscopy are provided in the context of signal dynamic range and accuracy of measured fluorophores’ emission spectra. To show potential applications, a five-colour cell immunofluorescence imaging experiment is theoretically simulated. Simulation results indicate that the use of proposed full-spectrum imaging technique may result in three times improvement in signal dynamic range compared to that can be achieved in the filter-based imaging. PMID:22356127
Student Experiments on the Effects of Dam Removal on the Elwha River
NASA Astrophysics Data System (ADS)
Sandland, T. O.; Grack Nelson, A. L.
2006-12-01
The National Center for Earth Surface Dynamics (NCED) is an NSF funded Science and Technology Center devoted to developing a quantitative, predictive science of the ecological and physical processes that define and shape rivers and river networks. The Science Museum of Minnesota's (SMM) Earthscapes River Restoration classes provide k-12 students, teachers, and the public opportunities to explore NCED concepts and, like NCED scientists, move from a qualitative to a quantitative-based understanding of river systems. During a series of classes, students work with an experimental model of the Elwha River in Washington State to gain an understanding of the processes that define and shape river systems. Currently, two large dams on the Elwha are scheduled for removal to restore salmon habitat. Students design different dam removal scenarios to test and make qualitative observations describing and comparing how the modeled system evolves over time. In a following session, after discussing the ambiguity of the previous session's qualitative data, student research teams conduct a quantitative experiment to collect detailed measurements of the system. Finally, students interpret, critique, and compare the data the groups collected and ultimately develop and advocate a recommendation for the "ideal" dam removal scenario. SMM is currently conducting a formative evaluation of River Restoration classes to improve their educational effectiveness and guide development of an educator's manual. As of August 2006, pre- and post-surveys have been administered to 167 students to gauge student learning and engagement. The surveys have found the program successful in teaching students why scientists use river models and what processes and phenomena are at work in river systems. Most notable is the increase in student awareness of sediment in river systems. A post-visit survey was also administered to 20 teachers who used the models in their classrooms. This survey provided feedback about teachers' experience with the program and will help inform the development of a future educator's manual. All teachers found the program to be effective at providing opportunities for students to make qualitative observations and most (95%) found the program effective at providing students opportunities to make quantitative measurements. A full summary of evaluation results will be shared at the meeting.
The integration of creative drama into science teaching
NASA Astrophysics Data System (ADS)
Arieli, Bracha (Bari)
This study explored the inclusion of creative drama into science teaching as an instructional strategy for enhancing elementary school students' understanding of scientific concepts. A treatment group of sixth grade students was taught a Full Option Science System (FOSS) science unit on Mixtures and Solutions with the addition of creative drama while a control group was taught using only the FOSS teaching protocol. Quantitative and qualitative data analyses demonstrated that students who studied science through creative drama exhibited a greater understanding of scientific content of the lessons and preferred learning science through creative drama. Treatment group students stated that they enjoyed participating in the activities with their friends and that the creative drama helped them to better understand abstract scientific concepts. Teachers involved with the creative drama activities were positively impressed and believed creative drama is a good tool for teaching science. Observations revealed that creative drama created a positive classroom environment, improved social interactions and self-esteem, that all students enjoyed creative drama, and that teachers' teaching style affected students' use of creative drama. The researcher concluded that the inclusion of creative drama with the FOSS unit enhanced students' scientific knowledge and understanding beyond that of the FOSS unit alone, that both teachers and students reacted positively to creative drama in science and that creative drama requires more time.
Su, Rui; Wang, Xinchen; Hou, Changming; Yang, Meiling; Huang, Keke; Chen, Huanwen
2017-09-01
Rapid qualitative and quantitative analysis of solid samples (e.g., pharmaceutical preparations) by using a small and low-resolution mass spectrometer without MS/MS function is still a challenge in ambient pressure ionization mass spectrometric analysis. Herein, a practically efficient method termed microwave-enhanced in-source decay (MEISD) using microwave plasma torch desorption ionization coupled with time-of-flight mass spectrometry (MPTDI-TOF MS) was developed for fast analysis of pharmaceutical tablets using a miniature TOF mass spectrometer without tandem mass function. The intensity of ISD fragmentation was evaluated under different microwave power values. Several factors, including desorption distance and time that might affect the signal intensity and fragmentation, were systematically investigated. It was observed that both the protonated molecular ions and major fragment ions from the active ingredients in tablets could be found in the full-scan mass spectra in positive ion mode, which were comparable to those obtained by a commercial LTQ-XL ion trap mass spectrometer. The structures of the ingredients could be elucidated in detail using the MEISD method, which promotes our understanding of the desorption/ionization processes in microwave plasma torch (MPT). Quantitative analysis of 10 tablets was achieved by full-scan MPTDI-TOF MS with low limit of detection (LOD, 0.763 mg/g), acceptable relative standard deviation (RSD < 7.33%, n =10), and 10 s for each tablet, showing promising applications in high throughput screening of counterfeit drugs. Graphical Abstract ᅟ.
NASA Astrophysics Data System (ADS)
Su, Rui; Wang, Xinchen; Hou, Changming; Yang, Meiling; Huang, Keke; Chen, Huanwen
2017-09-01
Rapid qualitative and quantitative analysis of solid samples (e.g., pharmaceutical preparations) by using a small and low-resolution mass spectrometer without MS/MS function is still a challenge in ambient pressure ionization mass spectrometric analysis. Herein, a practically efficient method termed microwave-enhanced in-source decay (MEISD) using microwave plasma torch desorption ionization coupled with time-of-flight mass spectrometry (MPTDI-TOF MS) was developed for fast analysis of pharmaceutical tablets using a miniature TOF mass spectrometer without tandem mass function. The intensity of ISD fragmentation was evaluated under different microwave power values. Several factors, including desorption distance and time that might affect the signal intensity and fragmentation, were systematically investigated. It was observed that both the protonated molecular ions and major fragment ions from the active ingredients in tablets could be found in the full-scan mass spectra in positive ion mode, which were comparable to those obtained by a commercial LTQ-XL ion trap mass spectrometer. The structures of the ingredients could be elucidated in detail using the MEISD method, which promotes our understanding of the desorption/ionization processes in microwave plasma torch (MPT). Quantitative analysis of 10 tablets was achieved by full-scan MPTDI-TOF MS with low limit of detection (LOD, 0.763 mg/g), acceptable relative standard deviation (RSD < 7.33%, n =10), and 10 s for each tablet, showing promising applications in high throughput screening of counterfeit drugs. [Figure not available: see fulltext.
ERIC Educational Resources Information Center
Matthews, Kelly E.; Adams, Peter; Goos, Merrilyn
2015-01-01
In this study, the Science Student Skills Inventory was used to gain understanding of student perceptions about their quantitative skills and compare perceptions of cohorts graduating before and after the implementation of a new science curriculum intent on developing quantitative skills. The study involved 600 responses from final-year…
Doing Quantitative Research in Education with SPSS
ERIC Educational Resources Information Center
Muijs, Daniel
2004-01-01
This book looks at quantitative research methods in education. The book is structured to start with chapters on conceptual issues and designing quantitative research studies before going on to data analysis. While each chapter can be studied separately, a better understanding will be reached by reading the book sequentially. This book is intended…
Multiblob coarse-graining for mixtures of long polymers and soft colloids
NASA Astrophysics Data System (ADS)
Locatelli, Emanuele; Capone, Barbara; Likos, Christos N.
2016-11-01
Soft nanocomposites represent both a theoretical and an experimental challenge due to the high number of the microscopic constituents that strongly influence the behaviour of the systems. An effective theoretical description of such systems invokes a reduction of the degrees of freedom to be analysed, hence requiring the introduction of an efficient, quantitative, coarse-grained description. We here report on a novel coarse graining approach based on a set of transferable potentials that quantitatively reproduces properties of mixtures of linear and star-shaped homopolymeric nanocomposites. By renormalizing groups of monomers into a single effective potential between a f-functional star polymer and an homopolymer of length N0, and through a scaling argument, it will be shown how a substantial reduction of the to degrees of freedom allows for a full quantitative description of the system. Our methodology is tested upon full monomer simulations for systems of different molecular weight, proving its full predictive potential.
Polak, Louisa; Green, Judith
2015-04-01
A large literature informs guidance for GPs about communicating quantitative risk information so as to facilitate shared decision making. However, relatively little has been written about how patients utilise such information in practice. To understand the role of quantitative risk information in patients' accounts of decisions about taking statins. This was a qualitative study, with participants recruited and interviewed in community settings. Semi-structured interviews were conducted with 34 participants aged >50 years, all of whom had been offered statins. Data were analysed thematically, using elements of the constant comparative method. Interviewees drew frequently on numerical test results to explain their decisions about preventive medication. In contrast, they seldom mentioned quantitative risk information, and never offered it as a rationale for action. Test results were spoken of as objects of concern despite an often-explicit absence of understanding, so lack of understanding seems unlikely to explain the non-use of risk estimates. Preventive medication was seen as 'necessary' either to treat test results, or because of personalised, unequivocal advice from a doctor. This study's findings call into question the assumption that people will heed and use numerical risk information once they understand it; these data highlight the need to consider the ways in which different kinds of knowledge are used in practice in everyday contexts. There was little evidence from this study that understanding probabilistic risk information was a necessary or valued condition for making decisions about statin use. © British Journal of General Practice 2015.
Research philosophy: towards an understanding.
Crossan, Frank
2003-01-01
In this paper, Frank Crossan argues that the distinction between quantitative and qualitative philosophies and research methods is sometimes overstated, and that triangulation of methods in contemporary research is common. It is, therefore, important to understand the strengths and weaknesses of each approach, and this paper aims to provide the novice researcher with a basis for developing that understanding. A descriptive analysis of the philosophies of positivism and post-positivist thinking in relation to research methodology is presented both as an introduction to the philosophical basis of research, and as a sound basis from which to discuss the 'quantitative-qualitative' debate.
17 CFR 244.100 - General rules regarding disclosure of non-GAAP financial measures.
Code of Federal Regulations, 2010 CFR
2010-04-01
... (2) A reconciliation (by schedule or other clearly understandable method), which shall be quantitative for historical non-GAAP measures presented, and quantitative, to the extent available without...
Ohtsuki, Sumio; Hirayama, Mio; Ito, Shingo; Uchida, Yasuo; Tachikawa, Masanori; Terasaki, Tetsuya
2014-06-01
The blood-brain barrier (BBB) is formed by brain capillary endothelial cells linked together via complex tight junctions, and serves to prevent entry of drugs into the brain. Multiple transporters are expressed at the BBB, where they control exchange of materials between the circulating blood and brain interstitial fluid, thereby supporting and protecting the CNS. An understanding of the BBB is necessary for efficient development of CNS-acting drugs and to identify potential drug targets for treatment of CNS diseases. Quantitative targeted proteomics can provide detailed information on protein expression levels at the BBB. The present review highlights the latest applications of quantitative targeted proteomics in BBB research, specifically to evaluate species and in vivo-in vitro differences, and to reconstruct in vivo transport activity. Such a BBB quantitative proteomics approach can be considered as pharmacoproteomics.
TU-B-304-02: Quantitative FMEA of TG-142
DOE Office of Scientific and Technical Information (OSTI.GOV)
O’Daniel, J.
2015-06-15
Although published in 2009, the AAPM TG-142 report on accelerator quality assurance still proves a challenge for full clinical implementation. The choice of methodologies to satisfy TG-142 requirements is critical to a successful application. Understanding the philosophy of TG-142 can help in creating an institution-specific QA practice that is both efficient and effective. The concept of maintaining commissioned beam profiles is still found confusing. The physicist must also consider technologies not covered by TG-142 (i.e. arc therapy techniques). On the horizon is TG-198 report on implementing TG-142. Although the community still lacks a final TG-100 report, performing a failure-mode -and-effectsmore » analysis and statistical process control analysis to determine the institution-specific clinical impact of each TG-142 test may be useful for identifying trends for pro-active surveillance. Learning Objectives: To better understand the confusing and controversial aspects of TG-142. To understand what is still missing from TG-142 and how to account for these tests in clinical practice To describe which QA tests in TG-142 yield the largest potential clinical result if not discovered.« less
ERIC Educational Resources Information Center
Huang, Shu Rong; Palmer, Peter T.
2017-01-01
This paper describes a method for determination of trihalomethanes (THMs) in drinking water via solid-phase microextraction (SPME) GC/MS as a means to develop and improve student understanding of the use of GC/MS for qualitative and quantitative analysis. In the classroom, students are introduced to SPME, GC/MS instrumentation, and the use of MS…
ERIC Educational Resources Information Center
Flanagan, K. M.; Einarson, J.
2017-01-01
In a world filled with big data, mathematical models, and statistics, the development of strong quantitative skills is becoming increasingly critical for modern biologists. Teachers in this field must understand how students acquire quantitative skills and explore barriers experienced by students when developing these skills. In this study, we…
ERIC Educational Resources Information Center
McLafferty, Charles L., Jr.; Slate, John R.; Onwuegbuzie, Anthony J.
2010-01-01
Quantitative research dominates published literature in the helping professions. Mixed methods research, which integrates quantitative and qualitative methodologies, has received a lukewarm reception. The authors address the iterative separation that infuses theory, praxis, philosophy, methodology, training, and public perception and propose a…
Quantitative Assays for RAS Pathway Proteins and Phosphorylation States
The NCI CPTAC program is applying its expertise in quantitative proteomics to develop assays for RAS pathway proteins. Targets include key phosphopeptides that should increase our understanding of how the RAS pathway is regulated.
US Consumers' Understanding of Nutrition Labels in 2013: The Importance of Health Literacy.
Persoskie, Alexander; Hennessy, Erin; Nelson, Wendy L
2017-09-28
We examined US adults' understanding of a Nutrition Facts panel (NFP), which requires health literacy (ie, prose, document, and quantitative literacy skills), and the association between label understanding and dietary behavior. Data were from the Health Information National Trends Survey, a nationally representative survey of health information seeking among US adults (N = 3,185) conducted from September 6, 2013, through December 30, 2013. Participants viewed an ice cream nutrition label and answered 4 questions that tested their ability to apply basic arithmetic and understanding of percentages to interpret the label. Participants reported their intake of sugar-sweetened soda, fruits, and vegetables. Regression analyses tested associations among label understanding, demographic characteristics, and self-reported dietary behaviors. Approximately 24% of people could not determine the calorie content of the full ice-cream container, 21% could not estimate the number of servings equal to 60 g of carbohydrates, 42% could not estimate the effect on daily calorie intake of foregoing 1 serving, and 41% could not calculate the percentage daily value of calories in a single serving. Higher scores for label understanding were associated with consuming more vegetables and less sugar-sweetened soda, although only the association with soda consumption remained significant after adjusting for demographic factors. Many consumers have difficulty interpreting nutrition labels, and label understanding correlates with self-reported dietary behaviors. The 2016 revised NFP labels may address some deficits in consumer understanding by eliminating the need to perform certain calculations (eg, total calories per package). However, some tasks still require the ability to perform calculations (eg, percentage daily value of calories). Schools have a role in teaching skills, such as mathematics, needed for nutrition label understanding.
Karlberg, Micael; von Stosch, Moritz; Glassey, Jarka
2018-03-07
In today's biopharmaceutical industries, the lead time to develop and produce a new monoclonal antibody takes years before it can be launched commercially. The reasons lie in the complexity of the monoclonal antibodies and the need for high product quality to ensure clinical safety which has a significant impact on the process development time. Frameworks such as quality by design are becoming widely used by the pharmaceutical industries as they introduce a systematic approach for building quality into the product. However, full implementation of quality by design has still not been achieved due to attrition mainly from limited risk assessment of product properties as well as the large number of process factors affecting product quality that needs to be investigated during the process development. This has introduced a need for better methods and tools that can be used for early risk assessment and predictions of critical product properties and process factors to enhance process development and reduce costs. In this review, we investigate how the quantitative structure-activity relationships framework can be applied to an existing process development framework such as quality by design in order to increase product understanding based on the protein structure of monoclonal antibodies. Compared to quality by design, where the effect of process parameters on the drug product are explored, quantitative structure-activity relationships gives a reversed perspective which investigates how the protein structure can affect the performance in different unit operations. This provides valuable information that can be used during the early process development of new drug products where limited process understanding is available. Thus, quantitative structure-activity relationships methodology is explored and explained in detail and we investigate the means of directly linking the structural properties of monoclonal antibodies to process data. The resulting information as a decision tool can help to enhance the risk assessment to better aid process development and thereby overcome some of the limitations and challenges present in QbD implementation today.
Lorenz, Kim; Cohen, Barak A.
2012-01-01
Quantitative trait loci (QTL) with small effects on phenotypic variation can be difficult to detect and analyze. Because of this a large fraction of the genetic architecture of many complex traits is not well understood. Here we use sporulation efficiency in Saccharomyces cerevisiae as a model complex trait to identify and study small-effect QTL. In crosses where the large-effect quantitative trait nucleotides (QTN) have been genetically fixed we identify small-effect QTL that explain approximately half of the remaining variation not explained by the major effects. We find that small-effect QTL are often physically linked to large-effect QTL and that there are extensive genetic interactions between small- and large-effect QTL. A more complete understanding of quantitative traits will require a better understanding of the numbers, effect sizes, and genetic interactions of small-effect QTL. PMID:22942125
Quantitative proteomics to study carbapenem resistance in Acinetobacter baumannii
Tiwari, Vishvanath; Tiwari, Monalisa
2014-01-01
Acinetobacter baumannii is an opportunistic pathogen causing pneumonia, respiratory infections and urinary tract infections. The prevalence of this lethal pathogen increases gradually in the clinical setup where it can grow on artificial surfaces, utilize ethanol as a carbon source. Moreover it resists desiccation. Carbapenems, a β-lactam, are the most commonly prescribed drugs against A. baumannii. Resistance against carbapenem has emerged in Acinetobacter baumannii which can create significant health problems and is responsible for high morbidity and mortality. With the development of quantitative proteomics, a considerable progress has been made in the study of carbapenem resistance of Acinetobacter baumannii. Recent updates showed that quantitative proteomics has now emerged as an important tool to understand the carbapenem resistance mechanism in Acinetobacter baumannii. Present review also highlights the complementary nature of different quantitative proteomic methods used to study carbapenem resistance and suggests to combine multiple proteomic methods for understanding the response to antibiotics by Acinetobacter baumannii. PMID:25309531
ERIC Educational Resources Information Center
Kara, Nuri
2018-01-01
The purpose of this study was to investigate university students' thoughts and practices concerning digital citizenship. An explanatory mixed methods design was used, and it involved collecting qualitative data after a quantitative phase in order to follow up on the quantitative data in more depth. In the first quantitative phase of the study, a…
Density Relaxation of Liquid-Vapor Critical Fluids Examined in Earth's Gravity
NASA Technical Reports Server (NTRS)
Wilkinson, R. Allen
2000-01-01
This work shows quantitatively the pronounced differences between the density equilibration of very compressible dense fluids in Earth's gravity and those in microgravity. The work was performed onsite at the NASA Glenn Research Center at Lewis Field and is complete. Full details are given in references 1 and 2. Liquid-vapor critical fluids (e.g., water) at their critical temperature and pressure, are very compressible. They collapse under their own weight in Earth's gravity, allowing only a thin meniscus-like layer with the critical pressure to survive. This critical layer, however, greatly slows down the equilibration process of the entire sample. A complicating feature is the buoyancy-driven slow flows of layers of heavier and lighter fluid. This work highlights the incomplete understanding of the hydrodynamics involved in these fluids.
Morales-Rivas, Lucia; González-Orive, Alejandro; Garcia-Mateo, Carlos; Hernández-Creus, Alberto; Caballero, Francisca G; Vázquez, Luis
2015-11-25
The full understanding of the deformation mechanisms in nanostructured bainite requires the local characterization of its mechanical properties, which are expected to change from one phase, bainitic ferrite, to another, austenite. This study becomes a challenging process due to the bainitic nanostructured nature and high Young's modulus. In this work, we have carried out such study by means of the combination of AFM-based techniques, such as nanoindentation and Peak Force Quantitative Nanomechanical Mapping (PF-QNM) measurements. We have addressed critically the limits and advantages of these techniques and been able to measure some elastoplastic parameters of both phases. Specifically, we have analyzed by PF-QNM two nanostructured bainitic steels, with a finer and a coarser structure, and found that both phases have a similar Young's modulus.
Coupling Processes Between Atmospheric Chemistry and Climate
NASA Technical Reports Server (NTRS)
Ko, Malcolm K. W.; Weisenstein, Debra; Shia, Run-Lie; Sze, N. D.
1998-01-01
The overall objective of this project is to improve the understanding of coupling processes between atmospheric chemistry and climate. Model predictions of the future distributions of trace gases in the atmosphere constitute an important component of the input necessary for quantitative assessments of global change. We will concentrate on the changes in ozone and stratospheric sulfate aerosol, with emphasis on how ozone in the lower stratosphere would respond to natural or anthropogenic changes. The key modeling tools for this work are the AER 2-dimensional chemistry-transport model, the AER 2-dimensional stratospheric sulfate model, and the AER three-wave interactive model with full chemistry. We will continue developing our three-wave model so that we can help NASA determine the strength and weakness of the next generation assessment models.
Coupling Processes Between Atmospheric Chemistry and Climate
NASA Technical Reports Server (NTRS)
Ko, M. K. W.; Weisenstein, Debra; Shia, Run-Lie; Sze, N. D.
1998-01-01
The overall objective of this project is to improve the understanding of coupling processes between atmospheric chemistry and climate. Model predictions of the future distributions of trace gases in the atmosphere constitute an important component of the input necessary for quantitative assessments of global change. We will concentrate on the changes in ozone and stratospheric sulfate aerosol, with emphasis on how ozone in the lower stratosphere would respond to natural or anthropogenic changes. The key modeling tools for this work are the AER two-dimensional chemistry-transport model, the AER two-dimensional stratospheric sulfate model, and the AER three-wave interactive model with full chemistry. We will continue developing our three-wave model so that we can help NASA determine the strength and weakness of the next generation assessment models.
NASA Astrophysics Data System (ADS)
Janssen, Paul; Wouters, Steinar H. W.; Cox, Matthijs; Koopmans, Bert
2013-11-01
In recent years, it was discovered that the current through an organic semiconductor, sandwiched between two non-magnetic electrodes, can be changed significantly by applying a small magnetic field. This surprisingly large magnetoresistance effect, often dubbed as organic magnetoresistance (OMAR), has puzzled the young field of organic spintronics during the last decade. Here, we present a detailed study on the voltage and temperature dependence of OMAR, aiming to unravel the lineshapes of the magnetic field effects and thereby gain a deeper fundamental understanding of the underlying microscopic mechanism. Using a full quantitative analysis of the lineshapes, we are able to extract all linewidth parameters and the voltage and temperature dependencies are explained with a recently proposed trion mechanism. Moreover, explicit microscopic simulations show a qualitative agreement to the experimental results.
NASA Astrophysics Data System (ADS)
Rosenberg, Peter; Shi, Hao; Zhang, Shiwei
2017-12-01
We present an ab initio, numerically exact study of attractive fermions in square lattices with Rashba spin-orbit coupling. The ground state of this system is a supersolid, with coexisting charge and superfluid order. The superfluid is composed of both singlet and triplet pairs induced by spin-orbit coupling. We perform large-scale calculations using the auxiliary-field quantum Monte Carlo method to provide the first full, quantitative description of the charge, spin, and pairing properties of the system. In addition to characterizing the exotic physics, our results will serve as essential high-accuracy benchmarks for the intense theoretical and especially experimental efforts in ultracold atoms to realize and understand an expanding variety of quantum Hall and topological superconductor systems.
Addison, P F E; Flander, L B; Cook, C N
2015-02-01
Protected area management agencies are increasingly using management effectiveness evaluation (MEE) to better understand, learn from and improve conservation efforts around the globe. Outcome assessment is the final stage of MEE, where conservation outcomes are measured to determine whether management objectives are being achieved. When quantitative monitoring data are available, best-practice examples of outcome assessments demonstrate that data should be assessed against quantitative condition categories. Such assessments enable more transparent and repeatable integration of monitoring data into MEE, which can promote evidence-based management and improve public accountability and reporting. We interviewed key informants from marine protected area (MPA) management agencies to investigate how scientific data sources, especially long-term biological monitoring data, are currently informing conservation management. Our study revealed that even when long-term monitoring results are available, management agencies are not using them for quantitative condition assessment in MEE. Instead, many agencies conduct qualitative condition assessments, where monitoring results are interpreted using expert judgment only. Whilst we found substantial evidence for the use of long-term monitoring data in the evidence-based management of MPAs, MEE is rarely the sole mechanism that facilitates the knowledge transfer of scientific evidence to management action. This suggests that the first goal of MEE (to enable environmental accountability and reporting) is being achieved, but the second and arguably more important goal of facilitating evidence-based management is not. Given that many MEE approaches are in their infancy, recommendations are made to assist management agencies realize the full potential of long-term quantitative monitoring data for protected area evaluation and evidence-based management. Copyright © 2014 Elsevier Ltd. All rights reserved.
School Leadership that Builds Teacher Social Capital
ERIC Educational Resources Information Center
Minckler, Cheri Hoff
2014-01-01
This quantitative study explores the relationship between school leadership and the development and sustenance of teacher social capital. The literature review discusses aspects of leadership theory to elucidate understanding of how leadership influences teachers' working relationships. Quantitative methodology and analyses ascertain the…
Quantitative characterization of 3D deformations of cell interactions with soft biomaterials
NASA Astrophysics Data System (ADS)
Franck, Christian
In recent years, the importance of mechanical forces in directing cellular function has been recognized as a significant factor in biological and physiological processes. In fact, these physical forces are now viewed equally as important as biochemical stimuli in controlling cellular response. Not only do these cellular forces, or cell tractions, play an important role in cell migration, they are also significant to many other physiological and pathological processes, both at the tissue and organ level, including wound healing, inflammation, angiogenesis, and embryogenesis. A complete quantification of cell tractions during cell-material interactions can lead to a deeper understanding of the fundamental role these forces play in cell biology. Thus, understanding the function and role of a cell from a mechanical framework can have important implications towards the development of new implant materials and drug treatments. Previous research has contributed significant descriptions of cell-tissue interactions by quantifying cell tractions in two-dimensional environments; however, most physiological processes are three-dimensional in nature. Recent studies have shown morphological differences in cells cultured on two-dimensional substrates versus three-dimensional matrices, and that the intrinsic extracellular matrix interactions and migration behavior are different in three dimensions versus two dimensions. Hence, measurement techniques are needed to investigate cellular behavior in all three dimensions. This thesis presents a full-field imaging technique capable of quantitatively measuring cell traction forces in all three spatial dimensions, and hence addresses the need of a three-dimensional quantitative imaging technique to gain insight into the fundamental role of physical forces in biological processes. The technique combines laser scanning confocal microscopy (LSCM) with digital volume correlation (DVC) to track the motion of fluorescent particles during cell-induced or externally applied deformations. This method is validated by comparing experimentally measured non-uniform deformation fields near hard and soft spherical inclusions under uniaxial compression with the corresponding analytical solution. Utilization of a newly developed computationally efficient stretch-correlation and deconvolution algorithm is shown to improve the overall measurement accuracy, in particular under large deformations. Using this technique, the full three-dimensional substrate displacement fields are experimentally determined during the migration of individual fibroblast cells on polyacrylamide gels. This is the first study to show the highly three-dimensional structure of cell-induced displacement and traction fields. These new findings suggest a three-dimensional push-pull cell motility, which differs from the traditional theories based on two-dimensional data. These results provide new insight into the dynamic cell-matrix force exchange or mechanotransduction of migrating cells, and will aid in the development of new three-dimensional cell motility and adhesion models. As this study reveals, the mechanical interactions of cells and their extracellular matrix appear to be highly three-dimensional. It also shows that the LSCM-DVC technique is well suited for investigating the mechanics of cell-matrix interactions while providing a platform to access detailed information of the intricate biomechanical coupling for many cellular responses. Thus, this method has the capability to provide direct quantitative experimental data showing how cells interact with their surroundings in three dimensions and might stimulate new avenues of scientific thought in understanding the fundamental role physical forces play in regulating cell behavior.
Cobb, Joshua N; Declerck, Genevieve; Greenberg, Anthony; Clark, Randy; McCouch, Susan
2013-04-01
More accurate and precise phenotyping strategies are necessary to empower high-resolution linkage mapping and genome-wide association studies and for training genomic selection models in plant improvement. Within this framework, the objective of modern phenotyping is to increase the accuracy, precision and throughput of phenotypic estimation at all levels of biological organization while reducing costs and minimizing labor through automation, remote sensing, improved data integration and experimental design. Much like the efforts to optimize genotyping during the 1980s and 1990s, designing effective phenotyping initiatives today requires multi-faceted collaborations between biologists, computer scientists, statisticians and engineers. Robust phenotyping systems are needed to characterize the full suite of genetic factors that contribute to quantitative phenotypic variation across cells, organs and tissues, developmental stages, years, environments, species and research programs. Next-generation phenotyping generates significantly more data than previously and requires novel data management, access and storage systems, increased use of ontologies to facilitate data integration, and new statistical tools for enhancing experimental design and extracting biologically meaningful signal from environmental and experimental noise. To ensure relevance, the implementation of efficient and informative phenotyping experiments also requires familiarity with diverse germplasm resources, population structures, and target populations of environments. Today, phenotyping is quickly emerging as the major operational bottleneck limiting the power of genetic analysis and genomic prediction. The challenge for the next generation of quantitative geneticists and plant breeders is not only to understand the genetic basis of complex trait variation, but also to use that knowledge to efficiently synthesize twenty-first century crop varieties.
Shorey, Shefaly; Yang, Yen Yen; Ang, Emily
2018-06-01
The aim of this study was to systematically retrieve, critique and synthesize available evidence regarding the association between negative childbirth experiences and future reproductive decisions. A child's birth is often a joyous event; however, there is a proportion of women who undergo negative childbirth experiences that have long-term implications on their reproductive decisions. A systematic review of quantitative studies was undertaken using Joanna Briggs Institute's methods. A search was carried out in CINAHL Plus with Full Text, Embase, PsycINFO, PubMed, Scopus and Web of Science from January 1996 - July 2016. Studies that fulfilled the inclusion criteria were assessed by two independent reviewers using the Joanna Briggs Institute's Critical Appraisal Tools. Data were extracted under subheadings adapted from the institute's data extraction forms. Twelve studies, which examined either one or more influences of negative childbirth experiences, were identified. The included studies were either cohort or cross-sectional designs. Five studies observed positive associations between prior negative childbirth experiences and decisions to not have another child, three studies found positive associations between negative childbirth experiences and decisions to delay a subsequent birth and six studies concluded positive associations between negative childbirth experiences and maternal requests for caesarean section in subsequent pregnancies. To receive a holistic understanding on negative childbirth experiences, a suitable definition and validated measuring tools should be used to understand this phenomenon. Future studies or reviews should include a qualitative component and/or the exploration of specific factors such as cultural and regional differences that influence childbirth experiences. © 2018 John Wiley & Sons Ltd.
Deformation and Failure Mechanisms of Shape Memory Alloys
DOE Office of Scientific and Technical Information (OSTI.GOV)
Daly, Samantha Hayes
2015-04-15
The goal of this research was to understand the fundamental mechanics that drive the deformation and failure of shape memory alloys (SMAs). SMAs are difficult materials to characterize because of the complex phase transformations that give rise to their unique properties, including shape memory and superelasticity. These phase transformations occur across multiple length scales (one example being the martensite-austenite twinning that underlies macroscopic strain localization) and result in a large hysteresis. In order to optimize the use of this hysteretic behavior in energy storage and damping applications, we must first have a quantitative understanding of this transformation behavior. Prior resultsmore » on shape memory alloys have been largely qualitative (i.e., mapping phase transformations through cracked oxide coatings or surface morphology). The PI developed and utilized new approaches to provide a quantitative, full-field characterization of phase transformation, conducting a comprehensive suite of experiments across multiple length scales and tying these results to theoretical and computational analysis. The research funded by this award utilized new combinations of scanning electron microscopy, diffraction, digital image correlation, and custom testing equipment and procedures to study phase transformation processes at a wide range of length scales, with a focus at small length scales with spatial resolution on the order of 1 nanometer. These experiments probe the basic connections between length scales during phase transformation. In addition to the insights gained on the fundamental mechanisms driving transformations in shape memory alloys, the unique experimental methodologies developed under this award are applicable to a wide range of solid-to-solid phase transformations and other strain localization mechanisms.« less
Numerical Evaluation of Parameter Correlation in the Hartmann-Tran Line Profile
NASA Astrophysics Data System (ADS)
Adkins, Erin M.; Reed, Zachary; Hodges, Joseph T.
2017-06-01
The partially correlated quadratic, speed-dependent hard-collision profile (pCqSDHCP), for simplicity referred to as the Hartmann-Tran profile (HTP), has been recommended as a generalized lineshape for high resolution spectroscopy. The HTP parameterizes complex collisional effects such as Dicke narrowing, speed dependent narrowing, and correlations between velocity-changing and dephasing collisions, while also simplifying to simpler profiles that are widely used, such as the Voigt profile. As advanced lineshape profiles are adopted by more researchers, it is important to understand the limitations that data quality has on the ability to retrieve physically meaningful parameters using sophisticated lineshapes that are fit to spectra of finite signal-to-noise ratio. In this work, spectra were simulated using the HITRAN Application Programming Interface (HAPI) across a full range of line parameters. Simulated spectra were evaluated to quantify the precision with which fitted lineshape parameters can be determined at a given signal-to-noise ratio, focusing on the numerical correlation between the retrieved Dicke narrowing frequency and the velocity-changing and dephasing collisions correlation parameter. Tran, H., N. Ngo, and J.-M. Hartmann, Journal of Quantitative Spectroscopy and Radiative Transfer 2013. 129: p. 89-100. Tennyson, et al., Pure Appl. Chem. 2014, 86: p. 1931-1943. Kochanov, R.V., et al., Journal of Quantitative Spectroscopy and Radiative Transfer 2016. 177: p. 15-30. Tran, H., N. Ngo, and J.-M. Hartmann, Journal of Quantitative Spectroscopy and Radiative Transfer 2013. 129: p. 199-203.
Jun, Yong Woong; Wang, Taejun; Hwang, Sekyu; Kim, Dokyoung; Ma, Donghee; Kim, Ki Hean; Kim, Sungjee; Jung, Junyang; Ahn, Kyo Han
2018-06-05
Vesicles exchange its contents through membrane fusion processes-kiss-and-run and full-collapse fusion. Indirect observation of these fusion processes using artificial vesicles enhanced our understanding on the molecular mechanisms involved. Direct observation of the fusion processes in a real biological system, however, remains a challenge owing to many technical obstacles. We disclose a ratiometric two-photon probe offering real-time tracking of lysosomal ATP with quantitative information for the first time. By applying the probe to two-photon live-cell imaging technique, lysosomal membrane fusion process in cells has been directly observed along with the concentration of its content-lysosomal ATP. Results show that the kiss-and-run process between lysosomes proceeds through repeating transient interactions with gradual content mixing, whereas the full-fusion process occurs at once. Furthermore, it is confirmed that both the fusion processes proceed with conservation of the content. Such a small-molecule probe exerts minimal disturbance and hence has potential for studying various biological processes associated with lysosomal ATP. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Understanding Periodicity as a Process with Gestalt Structure.
ERIC Educational Resources Information Center
Shama, Gilli
1998-01-01
Presents a two-phase investigation of how Israeli students understand the concept of periodicity. Discusses related research with teachers and students (N=895) employing both qualitative and quantitative research methodologies. Concludes that students understand periodicity as a process. Students' errors and preferences are discussed with…
ERIC Educational Resources Information Center
Moore, Kristen E.
2014-01-01
This non-experimental quantitative study investigated two groups of adult students who received academic advising from full-time faculty advisors or full-time non-faculty advisors. Differences in student satisfaction on three measures related to advisor availability, accuracy and perceived support for student educational goals were studied based…
Law, Martin; Ma, Wang-Kei; Lau, Damian; Chan, Eva; Yip, Lawrance; Lam, Wendy
2016-03-01
To quantitatively evaluate the cumulative effective dose and associated cancer risk for scoliotic patients undergoing repetitive full spine radiography during their diagnosis and follow up periods. Organ absorbed doses of full spine exposed scoliotic patients at different age were computer simulated with the use of PCXMC software. Gender specific effective dose was then calculated with the ICRP-103 approach. Values of lifetime attributable cancer risk for patients exposed at different age were calculated for both patient genders and for Asian and Western population. Mathematical fitting for effective dose and for lifetime attributable cancer risk, as function of exposed age, was analytically obtained to quantitatively estimate patient cumulated effective dose and cancer risk. The cumulative effective dose of full spine radiography with posteroanterior and lateral projection for patients exposed annually at age between 5 and 30 years using digital radiography system was calculated as 15mSv. The corresponding cumulative lifetime attributable cancer risk for Asian and Western population was calculated as 0.08-0.17%. Female scoliotic patients would be at a statistically significant higher cumulated cancer risk than male patients under the same full spine radiography protocol. We demonstrate the use of computer simulation and analytic formula to quantitatively obtain the cumulated effective dose and cancer risk at any age of exposure, both of which are valuable information to medical personnel and patients' parents concern about radiation safety in repetitive full spine radiography. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.
Compatibility of Qualitative and Quantitative Methods: Studying Child Sexual Abuse in America.
ERIC Educational Resources Information Center
Phelan, Patricia
1987-01-01
Illustrates how the combined use of qualitative and quantitative methods were necessary in obtaining a clearer understanding of the process of incest in American society. Argues that the exclusive use of one methodology would have obscured important information. (FMW)
76 FR 27326 - Agency Forms Undergoing Paperwork Reduction Act Review
Federal Register 2010, 2011, 2012, 2013, 2014
2011-05-11
.... Proposed Project Quantitative Survey of Physician Practices in Laboratory Test Ordering and Interpretation... Control and Prevention (CDC). Background and Brief Description The Quantitative Survey of Physician... collection. The survey will be funded in full by the Office of Surveillance, Epidemiology, and Laboratory...
Saitou, Takashi; Imamura, Takeshi
2016-01-01
Cell cycle progression is strictly coordinated to ensure proper tissue growth, development, and regeneration of multicellular organisms. Spatiotemporal visualization of cell cycle phases directly helps us to obtain a deeper understanding of controlled, multicellular, cell cycle progression. The fluorescent ubiquitination-based cell cycle indicator (Fucci) system allows us to monitor, in living cells, the G1 and the S/G2/M phases of the cell cycle in red and green fluorescent colors, respectively. Since the discovery of Fucci technology, it has found numerous applications in the characterization of the timing of cell cycle phase transitions under diverse conditions and various biological processes. However, due to the complexity of cell cycle dynamics, understanding of specific patterns of cell cycle progression is still far from complete. In order to tackle this issue, quantitative approaches combined with mathematical modeling seem to be essential. Here, we review several studies that attempted to integrate Fucci technology and mathematical models to obtain quantitative information regarding cell cycle regulatory patterns. Focusing on the technological development of utilizing mathematics to retrieve meaningful information from the Fucci producing data, we discuss how the combined methods advance a quantitative understanding of cell cycle regulation. © 2015 Japanese Society of Developmental Biologists.
NASA Astrophysics Data System (ADS)
Burton, Mike
2015-07-01
Magmatic degassing plays a key role in the dynamics of volcanic activity and also in contributing to the carbon, water and sulphur volatile cycles on Earth. Quantifying the fluxes of magmatic gas emitted from volcanoes is therefore of fundamental importance in Earth Science. This has been recognised since the beginning of modern volcanology, with initial measurements of volcanic SO2 flux being conducted with COrrelation SPECtrometer instruments from the late seventies. While COSPEC measurements continue today, they have been largely superseded by compact grating spectrometers, which were first introduced soon after the start of the 21st Century. Since 2006, a new approach to measuring fluxes has appeared, that of quantitative imaging of the SO2 slant column amount in a volcanic plume. Quantitative imaging of volcanic plumes has created new opportunities and challenges, and in April 2013 an ESF-funded MeMoVolC workshop was held, with the objectives of bringing together the main research groups, create a vibrant, interconnected, community, and examine the current state of the art of this new research frontier. This special issue of sixteen papers within the Journal of Volcanology and Geothermal Research is the direct result of the discussions, intercomparisons and results reported in that workshop. The papers report on the volcanological objectives of the plume imaging community, the state of the art of the technology used, intercomparisons, validations, novel methods and results from field applications. Quantitative plume imaging of volcanic plumes is achieved by using both infrared and ultraviolet wavelengths, with each wavelength offering a different trade-off of strengths and weaknesses, and the papers in this issue reflect this wavelength flexibility. Gas compositions can also be imaged, and this approach offers much promise in the quantification of chemical processing within plumes. One of the key advantages of the plume imaging approach is that we can achieve gas flux measurements at 1-10 Hz frequencies, allowing direct comparisons with geophysical measurements, opening new, interdisciplinary opportunities to deepen our understanding of volcanological processes. Several challenges still can be improved upon, such as dealing with light scattering issues and full automation of data processing. However, it is clear that quantitative plume imaging will have a lasting and profound impact on how volcano observatories operate, our ability to forecast and manage volcanic eruptions, our constraints of global volcanic gas fluxes, and on our understanding of magma dynamics.
Mixed methods research - the best of both worlds?
van Griensven, Hubert; Moore, Ann P; Hall, Valerie
2014-10-01
There has been a bias towards quantitative research approaches within manual therapy, which may have resulted in a narrow understanding of manual therapy practice. The aim of this Masterclass is to make a contribution to the expansion of methodologies used in manual therapy enquiry by discussing mixed methods research (MMR), a methodology which utilises both qualitative and quantitative methods within a single study in order to provide more comprehensive insights. To review rationales for MMR, as well as some of the common design options and potential difficulties. The paper also discusses theoretical frameworks that have been used to underpin qualitative and quantitative research, and ongoing debates about the possibility of combining them. Complexities associated with health and manual therapy cannot always be investigated satisfactorily by using a single research method. Some issues require a more comprehensive understanding, which may be provided by combining the strengths of quantitative and qualitative methods in a mixed methods study. Copyright © 2014 Elsevier Ltd. All rights reserved.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Mezyk, Stephen P.; Mincher, Bruce J.; Nilsson, Mikael
This document is the final report for the Nuclear Energy Universities Program (NEUP) grant 10-910 (DE-AC07-05ID14517) “Alpha Radiolysis of Nuclear Solvent Extraction Ligands used for An(III) and Ln(III) Separations”. The goal of this work was to obtain a quantitative understanding of the impacts of both low Linear Energy Transfer (LET, gamma-rays) and high LET (alpha particles) radiation chemistry occurring in future large-scale separations processes. This quantitative understanding of the major radiation effects on diluents and ligands is essential for optimal process implementation, and could result in significant cost savings in the future.
Quantitative and qualitative methods in medical education research: AMEE Guide No 90: Part II.
Tavakol, Mohsen; Sandars, John
2014-10-01
Abstract Medical educators need to understand and conduct medical education research in order to make informed decisions based on the best evidence, rather than rely on their own hunches. The purpose of this Guide is to provide medical educators, especially those who are new to medical education research, with a basic understanding of how quantitative and qualitative methods contribute to the medical education evidence base through their different inquiry approaches and also how to select the most appropriate inquiry approach to answer their research questions.
Quantitative and qualitative methods in medical education research: AMEE Guide No 90: Part I.
Tavakol, Mohsen; Sandars, John
2014-09-01
Medical educators need to understand and conduct medical education research in order to make informed decisions based on the best evidence, rather than rely on their own hunches. The purpose of this Guide is to provide medical educators, especially those who are new to medical education research, with a basic understanding of how quantitative and qualitative methods contribute to the medical education evidence base through their different inquiry approaches and also how to select the most appropriate inquiry approach to answer their research questions.
USDA-ARS?s Scientific Manuscript database
Drinking water contaminated with microbial pathogens can cause outbreaks of infectious disease, and these outbreaks are traditionally studied using epidemiologic methods. Quantitative microbial risk assessment (QMRA) can predict – and therefore help prevent – such outbreaks, but it has never been r...
Stocker, Elena; Toschkoff, Gregor; Sacher, Stephan; Khinast, Johannes G
2014-11-20
The purpose of this study is to evaluate the use of computer simulations for generating quantitative knowledge as a basis for risk ranking and mechanistic process understanding, as required by ICH Q9 on quality risk management systems. In this specific publication, the main focus is the demonstration of a risk assessment workflow, including a computer simulation for the generation of mechanistic understanding of active tablet coating in a pan coater. Process parameter screening studies are statistically planned under consideration of impacts on a potentially critical quality attribute, i.e., coating mass uniformity. Based on computer simulation data the process failure mode and effects analysis of the risk factors is performed. This results in a quantitative criticality assessment of process parameters and the risk priority evaluation of failure modes. The factor for a quantitative reassessment of the criticality and risk priority is the coefficient of variation, which represents the coating mass uniformity. The major conclusion drawn from this work is a successful demonstration of the integration of computer simulation in the risk management workflow leading to an objective and quantitative risk assessment. Copyright © 2014. Published by Elsevier B.V.
Seniors' Online Communities: A Quantitative Content Analysis
ERIC Educational Resources Information Center
Nimrod, Galit
2010-01-01
Purpose: To examine the contents and characteristics of seniors' online communities and to explore their potential benefits to older adults. Design and Methods: Quantitative content analysis of a full year's data from 14 leading online communities using a novel computerized system. The overall database included 686,283 messages. Results: There was…
Army Profession: How Effective Leadership Reinforces an Ethos of Trust
2016-06-10
of organizational trust continues to elude researchers .”59 According to Häkkinen (2012) “most trust research has been done by using quantitative ...following in the first issue of the Journal of Trust Research . “We have to maintain a proper balance between quantitative and qualitative methods with...life context to understand trust in Army organizations required to answer the research questions. Additionally, the survey method is a quantitative
Phenomenological Models and Animations of Welding and their Impact
NASA Astrophysics Data System (ADS)
DebRoy, Tarasankar
Professor Robertson's recognized research on metallurgical thermodynamics and kinetics for over 40 years facilitated the emergence of rigorous quantitative understanding of many complex metallurgical processes. The author had the opportunity to work with Professor Robertson on liquid metals in the 1970s. This paper is intended to review the advances in the quantitative understanding of welding processes and weld metal attributes in recent decades. Over this period, phenomenological models have been developed to better understand and control various welding processes and the structure and properties of welded materials. Numerical models and animations of melting, solidification and the evolution of micro and macro-structural features will be presented to critically examine their impact on the practice of welding and the underlying science.
NASA Astrophysics Data System (ADS)
Singla, Neeru; Dubey, Kavita; Srivastava, Vishal; Ahmad, Azeem; Mehta, D. S.
2018-02-01
We developed an automated high-resolution full-field spatial coherence tomography (FF-SCT) microscope for quantitative phase imaging that is based on the spatial, rather than the temporal, coherence gating. The Red and Green color laser light was used for finding the quantitative phase images of unstained human red blood cells (RBCs). This study uses morphological parameters of unstained RBCs phase images to distinguish between normal and infected cells. We recorded the single interferogram by a FF-SCT microscope for red and green color wavelength and average the two phase images to further reduced the noise artifacts. In order to characterize anemia infected from normal cells different morphological features were extracted and these features were used to train machine learning ensemble model to classify RBCs with high accuracy.
Participatory ergonomics for psychological factors evaluation in work system design.
Wang, Lingyan; Lau, Henry Y K
2012-01-01
It is a well recognized understanding that workers whose voice needs to be heard should be actively encouraged as full participants and involved in the early design stages of new ergonomic work system which encompass the development and implementation of new tools, workplaces, technologies or organizations. This paper presents a novel participatory strategy to evaluate three key psychological factors which are respectively mental fatigue, spiritual stress, and emotional satisfaction in work system design based on a modified version of Participatory Ergonomics (PE). In specific, it integrates a PE technique with a formulation view by combining the parallel development of PE strategies, frameworks and functions throughout the coverage of the entire work system design process, so as to bridge the gap between qualitative and quantitative analysis of psychological factors which can cause adverse or advantageous effects on worker's physiological and behavioral performance.
A Study on the Effects of Ball Defects on the Fatigue Life in Hybrid Bearings
NASA Technical Reports Server (NTRS)
Tang, Ching-Yao; Foerster, Chad E.; O'Brien, Michael J.; Hardy, Brian S.; Goyal, Vinay K.; Nelson, Benjamin A.; Robinson, Ernest Y.; Ward, Peter C.; Hilton, Michael R.
2014-01-01
Hybrid ball bearings using silicon nitride ceramic balls with steel rings are increasingly being used in space mechanism applications due to their high wear resistance and long rolling contact fatigue life. However, qualitative and quantitative reports of the effects of ball defects that cause early fatigue failure are rare. We report on our approach to study these effects. Our strategy includes characterization of defects encountered in use, generation of similar defects in a laboratory setting, execution of full-scale bearing tests to obtain lifetimes, post-test characterization, and related finite-element modeling to understand the stress concentration of these defects. We have confirmed that at least one type of defect of appropriate size can significantly reduce fatigue life. Our method can be used to evaluate other defects as they occur or are encountered.
How Dark Are Radial Breathing Modes in Plasmonic Nanodisks?
Schmidt, Franz-Philipp; Losquin, Arthur; Hofer, Ferdinand; Hohenau, Andreas; Krenn, Joachim R; Kociak, Mathieu
2018-03-21
Due to a vanishing dipole moment, radial breathing modes in small flat plasmonic nanoparticles do not couple to light and have to be probed with a near-field source, as in electron energy loss spectroscopy (EELS). With increasing particle size, retardation gives rise to light coupling, enabling probing breathing modes optically or by cathodoluminescence (CL). Here, we investigate single silver nanodisks with diameters of 150-500 nm by EELS and CL in an electron microscope and quantify the EELS/CL ratio, which corresponds to the ratio of full to radiative damping of the breathing mode. For the investigated diameter range, we find the CL signal to increase by about 1 order of magnitude, in agreement with numerical simulations. Due to reciprocity, our findings corroborate former optical experiments and enable a quantitative understanding of the light coupling of dark plasmonic modes.
Durham, Justin; Raphael, Karen G.; Benoliel, Rafael; Ceusters, Werner; Michelotti, Ambra; Ohrbach, Richard
2015-01-01
This paper was initiated by a symposium, in which the present authors contributed, organised by the International RDC/TMD Consortium Network in March 2013. The purpose of the paper is to review the status of biobehavioural research – both quantitative and qualitative – related to orofacial pain with respect to the etiology, pathophysiology, diagnosis and management of orofacial pain conditions, and how this information can optimally be used for developing a structured orofacial pain classification system for research. In particular, we address: representation of psychosocial entities in classification systems, use of qualitative research to identify and understand the full scope of psychosocial entities and their interaction, and the usage of classification system for guiding treatment. We then provide recommendations for addressing these problems, including how ontological principles can inform this process. PMID:26257252
Morales-Rivas, Lucia; González-Orive, Alejandro; Garcia-Mateo, Carlos; Hernández-Creus, Alberto; Caballero, Francisca G.; Vázquez, Luis
2015-01-01
The full understanding of the deformation mechanisms in nanostructured bainite requires the local characterization of its mechanical properties, which are expected to change from one phase, bainitic ferrite, to another, austenite. This study becomes a challenging process due to the bainitic nanostructured nature and high Young’s modulus. In this work, we have carried out such study by means of the combination of AFM-based techniques, such as nanoindentation and Peak Force Quantitative Nanomechanical Mapping (PF-QNM) measurements. We have addressed critically the limits and advantages of these techniques and been able to measure some elastoplastic parameters of both phases. Specifically, we have analyzed by PF-QNM two nanostructured bainitic steels, with a finer and a coarser structure, and found that both phases have a similar Young’s modulus. PMID:26602631
Brain and cognitive-behavioural development after asphyxia at term birth.
de Haan, Michelle; Wyatt, John S; Roth, Simon; Vargha-Khadem, Faraneh; Gadian, David; Mishkin, Mortimer
2006-07-01
Perinatal asphyxia occurs in approximately 1-6 per 1000 live full-term births. Different patterns of brain damage can result, though the relation of these patterns to long-term cognitive-behavioural outcome remains under investigation. The hippocampus is one brain region that can be damaged (typically not in isolation), and this site of damage has been implicated in two different long-term outcomes, cognitive memory impairment and the psychiatric disorder schizophrenia. Factors in addition to the acute episode of asphyxia likely contribute to these specific outcomes, making prediction difficult. Future studies that better document long-term cognitive-behavioural outcome, quantitatively identify patterns of brain injury over development and consider additional variables that may modulate the impact of asphyxia on cognitive and behavioural function will forward the goals of predicting long-term outcome and understanding the mechanisms by which it unfolds.
NASA Technical Reports Server (NTRS)
Underwood, Lauren
2013-01-01
TiO2 coated surfaces demonstrated both visually through photographic representation, and quantitatively, through reflectance measurements that they improved upon the current state of cleanliness upon the surfaces that they were applied to. TiO2 has the potential to both maintain and increase building s sustainability and the overall appearance of cleanliness TiO2 coated slides degraded soot under UV light compared to soot samples on plain uncoated slides under the same conditions Degradation of soot by photocatalysis was far more apparent than degradation of soot by UV light alone This demonstration provides the foundation for a laboratory model that could be used to simulate real world applications for photocatalytic materials Additional research is required to better understand the full potential of TiO2
Studying Biology to Understand Risk: Dosimetry Models and Quantitative Adverse Outcome Pathways
Confidence in the quantitative prediction of risk is increased when the prediction is based to as great an extent as possible on the relevant biological factors that constitute the pathway from exposure to adverse outcome. With the first examples now over 40 years old, physiologi...
6 Principles for Quantitative Reasoning and Modeling
ERIC Educational Resources Information Center
Weber, Eric; Ellis, Amy; Kulow, Torrey; Ozgur, Zekiye
2014-01-01
Encouraging students to reason with quantitative relationships can help them develop, understand, and explore mathematical models of real-world phenomena. Through two examples--modeling the motion of a speeding car and the growth of a Jactus plant--this article describes how teachers can use six practical tips to help students develop quantitative…
Conceptions and Practices of Assessment: A Case of Teachers Representing Improvement Conception
ERIC Educational Resources Information Center
Azis, Astuti
2015-01-01
Despite numerous quantitative studies on teachers' conceptions and practices of assessment, little research exists regarding the unique assessment environment of Indonesia. This study uses both quantitative and qualitative data to examine how Indonesian junior high school teachers understand assessment and how their conceptions of assessment…
ERIC Educational Resources Information Center
Tan, Cheng Yong
2017-01-01
The present study reviewed quantitative empirical studies examining the relationship between cultural capital and student achievement. Results showed that researchers had conceptualized and measured cultural capital in different ways. It is argued that the more holistic understanding of the construct beyond highbrow cultural consumption must be…
Quantitative Experiments to Explain the Change of Seasons
ERIC Educational Resources Information Center
Testa, Italo; Busarello, Gianni; Puddu, Emanuella; Leccia, Silvio; Merluzzi, Paola; Colantonio, Arturo; Moretti, Maria Ida; Galano, Silvia; Zappia, Alessandro
2015-01-01
The science education literature shows that students have difficulty understanding what causes the seasons. Incorrect explanations are often due to a lack of knowledge about the physical mechanisms underlying this phenomenon. To address this, we present a module in which the students engage in quantitative measurements with a photovoltaic panel to…
USDA-ARS?s Scientific Manuscript database
Quantitative microbial risk assessment (QMRA) is a valuable complement to epidemiology for understanding the health impacts of waterborne pathogens. The approach works by extrapolating available data in two ways. First, dose-response data are typically extrapolated from feeding studies, which use ...
USDA-ARS?s Scientific Manuscript database
Glutathione (GSH) plays an important role in maintaining redox homeostasis inside cells. Currently, there are no methods available to quantitatively assess the GSH concentration in live cells. Live cell fluorescence imaging revolutionized the understanding of cell biology and has become an indispens...
ERIC Educational Resources Information Center
Haegele, Justin A.; Hodge, Samuel R.
2015-01-01
Emerging professionals, particularly senior-level undergraduate and graduate students in kinesiology who have an interest in physical education for individuals with and without disabilities, should understand the basic assumptions of the quantitative research paradigm. Knowledge of basic assumptions is critical for conducting, analyzing, and…
The Methodological Underdog: A Review of Quantitative Research in the Key Adult Education Journals
ERIC Educational Resources Information Center
Boeren, Ellen
2018-01-01
An examination of articles published in leading adult education journals demonstrates that qualitative research dominates. To better understand this situation, a review of journal articles reporting on quantitative research has been undertaken by the author of this article. Differences in methodological strengths and weaknesses between…
Federal Register 2010, 2011, 2012, 2013, 2014
2013-12-17
... collecting qualitative and quantitative information. To support the qualitative analysis, HRSA will conduct... sites in order to gain a deeper understanding of the program's implementation. Finally, quantitative... forms; and 3. Client satisfaction surveys. ORHP is seeking approval from OMB for the three methods of...
ERIC Educational Resources Information Center
Caglayan, Günhan
2013-01-01
This study is about prospective secondary mathematics teachers' understanding and sense making of representational quantities generated by algebra tiles, the quantitative units (linear vs. areal) inherent in the nature of these quantities, and the quantitative addition and multiplication operations--referent preserving versus referent…
Assessing Student Understanding of Physical Hydrology
NASA Astrophysics Data System (ADS)
Castillo, A. J.; Marshall, J.; Cardenas, M. B.
2012-12-01
Our objective is to characterize and assess upper division and graduate student thinking by developing and testing an assessment tool for a physical hydrology class. The class' learning goals are: (1) Quantitative process-based understanding of hydrologic processes, (2) Experience with different methods in hydrology, (3) Learning, problem solving, communication skills. These goals were translated into two measurable tasks asked of students in a questionnaire: (1) Describe the significant processes in the hydrological cycle and (2) Describe laws governing these processes. A third question below assessed the students' ability to apply their knowledge: You have been hired as a consultant by __ to (1) assess how urbanization and the current drought have affected a local spring and (2) predict what the effects will be in the future if the drought continues. What information would you need to gather? What measurements would you make? What analyses would you perform? Student and expert responses to the questions were then used to develop a rubric to score responses. Using the rubric, 3 researchers independently blind-coded the full set of pre and post artifacts, resulting in 89% inter-rater agreement on the pre-tests and 83% agreement on the post-tests. We present student scores to illustrate the use of the rubric and to characterize student thinking prior to and following a traditional course. Most students interpreted Q1 in terms of physical processes affecting the water cycle, the primary organizing framework for hydrology, as intended. On the pre-test, one student scored 0, indicating no response, on this question. Twenty students scored 1, indicating rudimentary understanding, 2 students scored a 2, indicating a basic understanding, and no student scored a 3. Student scores on this question improved on the post-test. On the 22 post-tests that were blind scored, 11 students demonstrated some recognition of concepts, 9 students showed a basic understanding, and 2 students had a full understanding of the processes linked to hydrology. Half the students had provided evidence of the desired understanding; however, half still demonstrated only a rudimentary understanding. Results on Q2 were similar. On the pre-test, 2 students scored 0, 21 students scored 1, indicating rudimentary understanding, 2 students scored a 2, and no student scored a 3. On the post-test, again approximately half the students achieved the desired understanding: 9 students showed some recognition of concepts, 12 students demonstrated a basic understanding; only one student exhibited full understanding. On Q3, no student scored 0, 9 scored 1, 15 scored 2 and 1 student scored 3. On the post-test, one student scored 1, 16 students scored 2, and 5 students scored 3. Students were significantly better at responding to Q3 (the application) as opposed to Q1 and Q2, which were more abstract. Research has shown that students are often better able to solve contextualized problems when they are unable to deal with more abstract tasks. This result has limitations including the small number of participants, all from one institution, and the fact that the rubric was still under development. Nevertheless, the high inter-rater agreement by a group of experts is significant; the rubric we developed is a potentially useful tool for assessment of learning and understanding physical hydrology. Supported by NSF CAREER grant (EAR-0955750).
The Tentativeness of Scientific Theories: Conceptions of Pre-Service Science Teachers
ERIC Educational Resources Information Center
Jain, Jasmine; Abdullah, Nabilah; Lim, Beh Kian
2014-01-01
The recognition of sound understanding of Nature of Science (NOS) in promoting scientific literacy among individuals has heightened the need to probe NOS conceptions among various groups. However, the nature of quantitative studies in gauging NOS understanding has left the understanding on few NOS aspects insufficiently informed. This paper aimed…
Understanding Bullying through the Eyes of Youth
ERIC Educational Resources Information Center
Pister, Rebecca
2014-01-01
As reports of bullying continue to make headlines, the push to understand the processes behind bullying behaviors continues to rise. While a great deal of research has been conducted to better understand the processes behind and the outcomes of bullying, the majority of these studies are quantitative in nature and very few involve qualitative…
Introductory science and mathematics education for 21st-Century biologists.
Bialek, William; Botstein, David
2004-02-06
Galileo wrote that "the book of nature is written in the language of mathematics"; his quantitative approach to understanding the natural world arguably marks the beginning of modern science. Nearly 400 years later, the fragmented teaching of science in our universities still leaves biology outside the quantitative and mathematical culture that has come to define the physical sciences and engineering. This strikes us as particularly inopportune at a time when opportunities for quantitative thinking about biological systems are exploding. We propose that a way out of this dilemma is a unified introductory science curriculum that fully incorporates mathematics and quantitative thinking.
The mathematics of cancer: integrating quantitative models.
Altrock, Philipp M; Liu, Lin L; Michor, Franziska
2015-12-01
Mathematical modelling approaches have become increasingly abundant in cancer research. The complexity of cancer is well suited to quantitative approaches as it provides challenges and opportunities for new developments. In turn, mathematical modelling contributes to cancer research by helping to elucidate mechanisms and by providing quantitative predictions that can be validated. The recent expansion of quantitative models addresses many questions regarding tumour initiation, progression and metastases as well as intra-tumour heterogeneity, treatment responses and resistance. Mathematical models can complement experimental and clinical studies, but also challenge current paradigms, redefine our understanding of mechanisms driving tumorigenesis and shape future research in cancer biology.
Simon, Ted W; Simons, S Stoney; Preston, R Julian; Boobis, Alan R; Cohen, Samuel M; Doerrer, Nancy G; Fenner-Crisp, Penelope A; McMullin, Tami S; McQueen, Charlene A; Rowlands, J Craig
2014-08-01
The HESI RISK21 project formed the Dose-Response/Mode-of-Action Subteam to develop strategies for using all available data (in vitro, in vivo, and in silico) to advance the next-generation of chemical risk assessments. A goal of the Subteam is to enhance the existing Mode of Action/Human Relevance Framework and Key Events/Dose Response Framework (KEDRF) to make the best use of quantitative dose-response and timing information for Key Events (KEs). The resulting Quantitative Key Events/Dose-Response Framework (Q-KEDRF) provides a structured quantitative approach for systematic examination of the dose-response and timing of KEs resulting from a dose of a bioactive agent that causes a potential adverse outcome. Two concepts are described as aids to increasing the understanding of mode of action-Associative Events and Modulating Factors. These concepts are illustrated in two case studies; 1) cholinesterase inhibition by the pesticide chlorpyrifos, which illustrates the necessity of considering quantitative dose-response information when assessing the effect of a Modulating Factor, that is, enzyme polymorphisms in humans, and 2) estrogen-induced uterotrophic responses in rodents, which demonstrate how quantitative dose-response modeling for KE, the understanding of temporal relationships between KEs and a counterfactual examination of hypothesized KEs can determine whether they are Associative Events or true KEs.
A visual understanding of optical rotation using corn syrup
NASA Astrophysics Data System (ADS)
Nixon, M.; Hughes, I. G.
2017-07-01
In this paper a visual demonstration of optical rotation is presented, with content appropriate for use in a lecture demonstration as well as quantitative techniques suitable for an undergraduate-laboratory experiment. Linearly polarised lasers of various wavelengths are propagated through a glass tube containing corn syrup. The rotation of the plane of polarisation of the light is visible with the naked eye, making the experiment dramatic and engaging and aiding understanding of the phenomenon of optical rotation. In addition, we present a simple approach to quantitatively analyse data using only equipment commonly found in undergraduate teaching laboratories.
Kinetic Methods for Understanding Linker Exchange in Metal-Organic Frameworks
NASA Astrophysics Data System (ADS)
Morabito, Joseph V.
Exchange reactions have enabled a new level of control in the rational, stepwise preparation of metal-organic framework (MOF) materials. However, their full potential is limited by a lack of understanding of the molecular mechanisms by which they occur. This dissertation describes our efforts to understand this important class of reactions in two parts. The first reports our use of a linker exchange process to encapsulate guest molecules larger than the limiting pore aperture of the MOF. The concept is demonstrated, along with evidence for guest encapsulation and its relation to a dissociative linker exchange process. The second part describes our development of the first quantitative kinetic method for studying MOF linker exchange reactions and our application of this method to understand the solvent dependence of the reaction of ZIF-8 with imidazole. This project involved the collection of the largest set of rate data available on any MOF linker exchange reaction. The combination of this dataset with small molecule encapsulation experiments allowed us to formulate a mechanistic model that could account for all the observed kinetic and structural data. By comparison with the kinetic behavior of complexes in solution, we were able to fit the kinetic behavior of ZIF-8 into the broader family of coordination compounds. Aside from the specific use that our kinetic data may have in predicting the reactivity of ZIF linker exchange, we hope that the conceptual bridges made between MOFs and related metal?organic compounds can help reveal underlying patterns in behavior and advance the field.
ERIC Educational Resources Information Center
Nishiyama, Takeshi; Suzuki, Masako; Adachi, Katsunori; Sumi, Satoshi; Okada, Kensuke; Kishino, Hirohisa; Sakai, Saeko; Kamio, Yoko; Kojima, Masayo; Suzuki, Sadao; Kanne, Stephen M.
2014-01-01
We comprehensively compared all available questionnaires for measuring quantitative autistic traits (QATs) in terms of reliability and construct validity in 3,147 non-clinical and 60 clinical subjects with normal intelligence. We examined four full-length forms, the Subthreshold Autism Trait Questionnaire (SATQ), the Broader Autism Phenotype…
NASA Astrophysics Data System (ADS)
Ponticorvo, A.; Rowland, R.; Yang, B.; Lertsakdadet, B.; Crouzet, C.; Bernal, N.; Choi, B.; Durkin, A. J.
2017-02-01
Burn wounds are often characterized by injury depth, which then dictates wound management strategy. While most superficial burns and full thickness burns can be diagnosed through visual inspection, clinicians experience difficulty with accurate diagnosis of burns that fall between these extremes. Accurately diagnosing burn severity in a timely manner is critical for starting the appropriate treatment plan at the earliest time points to improve patient outcomes. To address this challenge, research groups have studied the use of commercial laser Doppler imaging (LDI) systems to provide objective characterization of burn-wound severity. Despite initial promising findings, LDI systems are not commonplace in part due to long acquisition times that can suffer from artifacts in moving patients. Commercial LDI systems are being phased out in favor of laser speckle imaging (LSI) systems that can provide similar information with faster acquisition speeds. To better understand the accuracy and usefulness of commercial LSI systems in burn-oriented research, we studied the performance of a commercial LSI system in three different sample systems and compared its results to a research-grade LSI system in the same environments. The first sample system involved laboratory measurements of intralipid (1%) flowing through a tissue simulating phantom, the second preclinical measurements in a controlled burn study in which wounds of graded severity were created on a Yorkshire pig, and the third clinical measurements involving a small sample of clinical patients. In addition to the commercial LSI system, a research grade LSI system that was designed and fabricated in our labs was used to quantitatively compare the performance of both systems and also to better understand the "Perfusion Unit" output of commercial systems.
3D Printing and Digital Rock Physics for Geomaterials
NASA Astrophysics Data System (ADS)
Martinez, M. J.; Yoon, H.; Dewers, T. A.
2015-12-01
Imaging techniques for the analysis of porous structures have revolutionized our ability to quantitatively characterize geomaterials. Digital representations of rock from CT images and physics modeling based on these pore structures provide the opportunity to further advance our quantitative understanding of fluid flow, geomechanics, and geochemistry, and the emergence of coupled behaviors. Additive manufacturing, commonly known as 3D printing, has revolutionized production of custom parts with complex internal geometries. For the geosciences, recent advances in 3D printing technology may be co-opted to print reproducible porous structures derived from CT-imaging of actual rocks for experimental testing. The use of 3D printed microstructure allows us to surmount typical problems associated with sample-to-sample heterogeneity that plague rock physics testing and to test material response independent from pore-structure variability. Together, imaging, digital rocks and 3D printing potentially enables a new workflow for understanding coupled geophysical processes in a real, but well-defined setting circumventing typical issues associated with reproducibility, enabling full characterization and thus connection of physical phenomena to structure. In this talk we will discuss the possibilities that these technologies can bring to geosciences and present early experiences with coupled multiscale experimental and numerical analysis using 3D printed fractured rock specimens. In particular, we discuss the processes of selection and printing of transparent fractured specimens based on 3D reconstruction of micro-fractured rock to study fluid flow characterization and manipulation. Micro-particle image velocimetry is used to directly visualize 3D single and multiphase flow velocity in 3D fracture networks. Sandia National Laboratories is a multi-program laboratory managed and operated by Sandia Corporation, a wholly owned subsidiary of Lockheed Martin Corporation, for the U.S. Department of Energy's National Nuclear Security Administration under contract DE-AC04-94AL85000.
Interfacial self-healing of nanocomposite hydrogels: Theory and experiment
NASA Astrophysics Data System (ADS)
Wang, Qiming; Gao, Zheming; Yu, Kunhao
2017-12-01
Polymers with dynamic bonds are able to self-heal their fractured interfaces and restore the mechanical strengths. It is largely elusive how to analytically model this self-healing behavior to construct the mechanistic relationship between the self-healing properties (e.g., healed interfacial strength and equilibrium healing time) and the material compositions and healing conditions. Here, we take a self-healable nanocomposite hydrogel as an example to illustrate an interfacial self-healing theory for hydrogels with dynamic bonds. In the theory, we consider the free polymer chains diffuse across the interface and reform crosslinks to bridge the interface. We analytically reveal that the healed strengths of nanocomposite hydrogels increase with the healing time in an error-function-like form. The equilibrium self-healing time of the full-strength recovery decreases with the temperature and increases with the nanoparticle concentration. We further analytically reveal that the healed interfacial strength decreases with increasing delaying time before the healing process. The theoretical results quantitatively match with our experiments on nanosilica hydrogels, and also agree well with other researchers' experiments on nanoclay hydrogels. We expect that this theory would open promising avenues for quantitative understanding of the self-healing mechanics of various polymers with dynamic bonds, and offer insights for designing high-performance self-healing polymers.
Lien, W P; Lee, Y S; Chang, F Z; Chen, J J; Shieh, W B
1978-01-01
Quantitative one-plane cineangiocardiography in right anterior oblique position for evaluation of LV performance was carried out in 62 patients with various heart diseases and in 13 subjects with normal LV. Parameters for evaluating both pump and muscle performances were derived from volume and pressure measurements. Of 31 patients with either systolic hypertension or LV myocardial diseases (coronary artery disease or idiopathic cardiomyopathy), 14 had clinical evidence of LV failure before the study. It was found that mean VCF and EF were most sensitive indicators of impaired LV performance among the various parameters. There was a close correlation between mean VCF and EF, yet discordant changes of both parameters were noted in some patients. Furthermore, wall motion abnormalities were not infrequently observed in patients with coronary artery disease or primary cardiomyopathy. Therefore, assessment of at least three ejection properties (EF, mean VCF and wall motion abnormalities) are considered to be essential for full understanding of derangement of LV function in heart disease. This is especially true of patients with coronary artery disease. LV behavior in relation to different pathological stresses or lesions, such as chronic pressure or volume load, myocardial disease and mitral stenosis, was also studied and possible cause of impaired LV myocardial function in mitral stenosis was discussed.
Leng, Yumin; Qian, Sihua; Wang, Yuhui; Lu, Cheng; Ji, Xiaoxu; Lu, Zhiwen; Lin, Hengwei
2016-01-01
Multidimensional sensing offers advantages in accuracy, diversity and capability for the simultaneous detection and discrimination of multiple analytes, however, the previous reports usually require complicated synthesis/fabrication process and/or need a variety of techniques (or instruments) to acquire signals. Therefore, to take full advantages of this concept, simple designs are highly desirable. Herein, a novel concept is conceived to construct multidimensional sensing platforms based on a single indicator that has capability of showing diverse color/fluorescence responses with the addition of different analytes. Through extracting hidden information from these responses, such as red, green and blue (RGB) alterations, a triple-channel-based multidimensional sensing platform could consequently be fabricated, and the RGB alterations are further applicable to standard statistical methods. As a proof-of-concept study, a triple-channel sensing platform is fabricated solely using dithizone with assistance of cetyltrimethylammonium bromide (CTAB) for hyperchromicity and sensitization, which demonstrates superior capabilities in detection and identification of ten common heavy metal ions at their standard concentrations of wastewater-discharge of China. Moreover, this sensing platform exhibits promising applications in semi-quantitative and even quantitative analysis individuals of these heavy metal ions with high sensitivity as well. Finally, density functional theory calculations are performed to reveal the foundations for this analysis. PMID:27146105
ERIC Educational Resources Information Center
Schochet, Peter Z.; Puma, Mike; Deke, John
2014-01-01
This report summarizes the complex research literature on quantitative methods for assessing how impacts of educational interventions on instructional practices and student learning differ across students, educators, and schools. It also provides technical guidance about the use and interpretation of these methods. The research topics addressed…
Federal Register 2010, 2011, 2012, 2013, 2014
2010-11-30
..., motivations, and feelings than do quantitative studies. Focus groups serve the narrowly defined need for direct and informal opinion on a specific topic and as a qualitative research tool have three major... quantitative studies, To better understand consumers' attitudes and emotions in response to topics and concepts...
Lisa A. Schulte; David J. Mladenoff; Erik V. Nordheim
2002-01-01
We developed a quantitative and replicable classification system to improve understanding of historical composition and structure within northern Wisconsin's forests. The classification system was based on statistical cluster analysis and two forest metrics, relative dominance (% basal area) and relative importance (mean of relative dominance and relative density...
Federal Register 2010, 2011, 2012, 2013, 2014
2013-12-02
... quantitative studies. Focus groups serve the narrowly defined need for direct and informal opinion on a specific topic and as a qualitative research tool have three major purposes: To obtain information that is useful for developing variables and measures for quantitative studies, To better understand people's...
Federal Register 2010, 2011, 2012, 2013, 2014
2013-06-28
...' attitudes, beliefs, motivations, and feelings than do quantitative studies. Focus groups serve the narrowly defined need for direct and informal opinion on a specific topic and as a qualitative research tool have... quantitative studies, To better understand people's attitudes and emotions in response to topics and concepts...
ERIC Educational Resources Information Center
Ojala, Maria
2008-01-01
Theories about ambivalence, as well as quantitative and qualitative empirical approaches, are applied to obtain an understanding of recycling among young adults. A questionnaire was mailed to 422 Swedish young people. Regression analyses showed that a mix of negative emotions (worry) and positive emotions (hope and joy) about the environmental…
ERIC Educational Resources Information Center
Yoshikawa, Hirokazu; Weisner, Thomas S.; Kalil, Ariel; Way, Niobe
2008-01-01
Multiple methods are vital to understanding development as a dynamic, transactional process. This article focuses on the ways in which quantitative and qualitative methodologies can be combined to enrich developmental science and the study of human development, focusing on the practical questions of "when" and "how." Research situations that may…
ERIC Educational Resources Information Center
Frazier, Thomas W.; Ratliff, Kristin R.; Gruber, Chris; Zhang, Yi; Law, Paul A.; Constantino, John N.
2014-01-01
Understanding the factor structure of autistic symptomatology is critical to the discovery and interpretation of causal mechanisms in autism spectrum disorder. We applied confirmatory factor analysis and assessment of measurement invariance to a large ("N" = 9635) accumulated collection of reports on quantitative autistic traits using…
Search PNNL Home About Research Publications Jobs News Contacts Computational Biology and Bioinformatics , and engineering to transform the data into knowledge. This new quantitative, predictive biology is to empirical modeling and physics-based simulations. CBB research seeks to: Understand. Understanding
ERIC Educational Resources Information Center
Ojose, Bobby
2015-01-01
This study investigated proportional reasoning and the related concepts of decimal, percent, and ratio. In particular, the research focused on analyzing the gaps and understandings that grades 6, 7, and 8 students have and advanced factors for such gaps and understandings. The study employed a mixed method approach in which quantitative data was…
Beidas, Rinad S; Wolk, Courtney L Benjamin; Walsh, Lucia M; Evans, Arthur C; Hurford, Matthew O; Barg, Frances K
2014-11-23
Organizational factors impact the delivery of mental health services in community settings. Mixed-methods analytic approaches have been recommended, though little research within implementation science has explicitly compared inductive and deductive perspectives to understand their relative value in understanding the same constructs. The purpose of our study is to use two different paradigmatic approaches to deepen our understanding of organizational social context. We accomplish this by using a mixed-methods approach in an investigation of organizational social context in community mental health clinics. Nineteen agencies, representing 23 sites, participated. Enrolled participants included 130 therapists, 36 supervisors, and 22 executive administrators. Quantitative data was obtained via the Organizational Social Context (OSC) measure. Qualitative data, comprised of direct observation with spot sampling generated from agency visits, was coded using content analysis and grounded theory. The present study examined elements of organizational social context that would have been missed if only quantitative data had been obtained and utilized mixed methods to investigate if stratifying observations based on quantitative ratings from the OSC resulted in the emergence of differential themes. Four of the six OSC constructs were commonly observed in field observations (i.e., proficiency, rigidity, functionality, stress), while the remaining two constructs were not frequently observed (i.e., resistance, engagement). Constructs emerged related to organizational social context that may have been missed if only quantitative measurement was employed, including those around the physical environment, commentary about evidence-based practice initiatives, leadership, cultural diversity, distrust, and affect. Stratifying agencies by "best," "average," and "worst" organizational social context impacted interpretation for three constructs (affect, stress, and leadership). Results support the additive value of integrating inductive and deductive perspectives in implementation science research. This synthesis of approaches facilitated a more comprehensive understanding and interpretation of the findings than would have been possible if either methodology had been employed in isolation.
Carroll, Linda J; Rothe, J Peter
2010-09-01
Like other areas of health research, there has been increasing use of qualitative methods to study public health problems such as injuries and injury prevention. Likewise, the integration of qualitative and quantitative research (mixed-methods) is beginning to assume a more prominent role in public health studies. Likewise, using mixed-methods has great potential for gaining a broad and comprehensive understanding of injuries and their prevention. However, qualitative and quantitative research methods are based on two inherently different paradigms, and their integration requires a conceptual framework that permits the unity of these two methods. We present a theory-driven framework for viewing qualitative and quantitative research, which enables us to integrate them in a conceptually sound and useful manner. This framework has its foundation within the philosophical concept of complementarity, as espoused in the physical and social sciences, and draws on Bergson's metaphysical work on the 'ways of knowing'. Through understanding how data are constructed and reconstructed, and the different levels of meaning that can be ascribed to qualitative and quantitative findings, we can use a mixed-methods approach to gain a conceptually sound, holistic knowledge about injury phenomena that will enhance our development of relevant and successful interventions.
Physiologic basis for understanding quantitative dehydration assessment.
Cheuvront, Samuel N; Kenefick, Robert W; Charkoudian, Nisha; Sawka, Michael N
2013-03-01
Dehydration (body water deficit) is a physiologic state that can have profound implications for human health and performance. Unfortunately, dehydration can be difficult to assess, and there is no single, universal gold standard for decision making. In this article, we review the physiologic basis for understanding quantitative dehydration assessment. We highlight how phenomenologic interpretations of dehydration depend critically on the type (dehydration compared with volume depletion) and magnitude (moderate compared with severe) of dehydration, which in turn influence the osmotic (plasma osmolality) and blood volume-dependent compensatory thresholds for antidiuretic and thirst responses. In particular, we review new findings regarding the biological variation in osmotic responses to dehydration and discuss how this variation can help provide a quantitative and clinically relevant link between the physiology and phenomenology of dehydration. Practical measures with empirical thresholds are provided as a starting point for improving the practice of dehydration assessment.
Science Literacy's Neglected Twin: Numeracy
NASA Astrophysics Data System (ADS)
Follette, K.; McCarthy, D.
2014-07-01
Have introductory astronomy courses moved too far toward qualitative science? By itself, qualitative understanding, even deep appreciation, of the scientific endeavor is insufficient to engender scientific literacy. In order to interpret scientific information encountered in daily life and to distinguish it from pseudoscience, our students must also be quantitatively savvy. A scientifically literate citizen should be able to employ arithmetic, interpret numbers in context, read graphs and tables, and confidently incorporate numbers in writing. A gentle quantitative emphasis permeates our introductory astronomy courses to help our students become aware of their numerical deficits and appreciate the value of numerical thinking. This approach not only helps transform students into more well-informed citizens and capable problem solvers but also helps them achieve a deeper understanding of course material. We present data from an educational study that documents the extent of quantitative illiteracy and shows that improvements in attitude and achievement are possible.
Gatti, Giulia; Bianchi, Carlo Nike; Parravicini, Valeriano; Rovere, Alessio; Peirano, Andrea; Montefalcone, Monica; Massa, Francesco; Morri, Carla
2015-01-01
Understanding the effects of environmental change on ecosystems requires the identification of baselines that may act as reference conditions. However, the continuous change of these references challenges our ability to define the true natural status of ecosystems. The so-called sliding baseline syndrome can be overcome through the analysis of quantitative time series, which are, however, extremely rare. Here we show how combining historical quantitative data with descriptive ‘naturalistic’ information arranged in a chronological chain allows highlighting long-term trends and can be used to inform present conservation schemes. We analysed the long-term change of a coralligenous reef, a marine habitat endemic to the Mediterranean Sea. The coralligenous assemblages of Mesco Reef (Ligurian Sea, NW Mediterranean) have been studied, although discontinuously, since 1937 thus making available both detailed descriptive information and scanty quantitative data: while the former was useful to understand the natural history of the ecosystem, the analysis of the latter was of paramount importance to provide a formal measure of change over time. Epibenthic assemblages remained comparatively stable until the 1990s, when species replacement, invasion by alien algae, and biotic homogenisation occurred within few years, leading to a new and completely different ecosystem state. The shift experienced by the coralligenous assemblages of Mesco Reef was probably induced by a combination of seawater warming and local human pressures, the latter mainly resulting in increased water turbidity; in turn, cumulative stress may have favoured the establishment of alien species. This study showed that the combined analysis of quantitative and descriptive historical data represent a precious knowledge to understand ecosystem trends over time and provide help to identify baselines for ecological management. PMID:25714413
ERIC Educational Resources Information Center
Bray, Nathaniel J.; Williams, Laine
2017-01-01
This study examined communication satisfaction and organisational commitment for professional staff at an American Master's institution using two quantitative surveys: Downs and Hazen's Communication Satisfaction Questionnaire and Meyer and Allen's TCM Employee Commitment Survey. One hundred and sixty-eight full-time and part-time staff…
Using Performance Tasks to Improve Quantitative Reasoning in an Introductory Mathematics Course
ERIC Educational Resources Information Center
Kruse, Gerald; Drews, David
2013-01-01
A full-cycle assessment of our efforts to improve quantitative reasoning in an introductory math course is described. Our initial iteration substituted more open-ended performance tasks for the active learning projects than had been used. Using a quasi-experimental design, we compared multiple sections of the same course and found non-significant…
The SIV plasma viral load assay performed by the Quantitative Molecular Diagnostics Core (QMDC) utilizes reagents specifically designed to detect and accurately quantify the full range of SIV/SHIV viral variants and clones in common usage in the rese
Progress and Strategies for Testing of Materials for Solar Panels
DOE Office of Scientific and Technical Information (OSTI.GOV)
Kurtz, Sarah
Accelerated testing is key to confident launch of a new product. However, for new products like solar panels, the best approach is not always clear. The challenge for materials manufacturers is that test times can be long. Also, small-coupon testing may not predict the behavior in the full-size module, but testing of the full-size module is too expensive. As a result, solar panel test standards like IEC 61215 are useful, but are not sufficient. Material manufacturers have needed to define their own test protocols. This presentation will review some historical data (e.g., data show that manufacturers are making great progressmore » toward reducing encapsulant discoloration) and describe advances in material testing (for example, new techniques are being demonstrated on how to more quantitatively assess adhesion, detect tendency for delamination, and understand how encapsulant properties affect other properties like cracking of cells). The International PV Quality Assurance Task Force has been researching climate-specific weathering tests toward the goal of defining international standards that would simplify qualification and quality assurance testing for materials. The status of these tests and the strategies for how to organize these standards to best meet the needs of the industry will be discussed.« less
Kisely, Stephen; Kendall, Elizabeth
2011-08-01
Papers using qualitative methods are increasingly common in psychiatric journals. This overview is an introduction to critically appraising a qualitative paper for clinicians who are more familiar with quantitative methods. Qualitative research uses data from interviews (semi-structured or unstructured), focus groups, observations or written materials. Data analysis is inductive, allowing meaning to emerge from the data, rather than the more deductive, hypothesis centred approach of quantitative research. This overview compares and contrasts quantitative and qualitative research methods. Quantitative concepts such as reliability, validity, statistical power, bias and generalisability have qualitative equivalents. These include triangulation, trustworthiness, saturation, reflexivity and applicability. Reflexivity also shares features of transference. Qualitative approaches include: ethnography, action-assessment, grounded theory, case studies and mixed methods. Qualitative research can complement quantitative approaches. An understanding of both is useful in critically appraising the psychiatric literature.
Appraising Quantitative Research in Health Education: Guidelines for Public Health Educators
Hayes, Sandra C.; Scharalda, Jeanfreau G.; Stetson, Barbara; Jones-Jack, Nkenge H.; Valliere, Matthew; Kirchain, William R.; Fagen, Michael; LeBlanc, Cris
2010-01-01
Many practicing health educators do not feel they possess the skills necessary to critically appraise quantitative research. This publication is designed to help provide practicing health educators with basic tools helpful to facilitate a better understanding of quantitative research. This article describes the major components—title, introduction, methods, analyses, results and discussion sections—of quantitative research. Readers will be introduced to information on the various types of study designs and seven key questions health educators can use to facilitate the appraisal process. Upon reading, health educators will be in a better position to determine whether research studies are well designed and executed. PMID:20400654
Environmental Systems Microbiology of Contaminated Environments
DOE Office of Scientific and Technical Information (OSTI.GOV)
Sayler, Gary; Hazen, Terry C.
Environmental Systems Microbiology is well positioned to move forward in dynamic complex system analysis probing new questions and developing new insight into the function, robustness and resilience in response to anthropogenic perturbations. Recent studies have demonstrated that natural bacterial communities can be used as quantitative biosensors in both groundwater and deep ocean water, predicting oil concentration from the Gulf of Mexico Deep Water Horizon spill and from groundwater at nuclear production waste sites (16, 17, 25). Since the first demonstration of catabolic gene expression in soil remediation (34) it has been clear that extension beyond organismal abundance to process andmore » function of microbial communities as a whole using the whole suite of omic tools available to the post genomic era. Metatranscriptomics have been highlighted as a prime vehicle for understanding responses to environmental drivers (35) in complex systems and with rapidly developing metabolomics, full functional understanding of complex community biogeochemical cycling is an achievable goal. Perhaps more exciting is the dynamic nature of these systems and their complex adaptive strategies that may lead to new control paradigms and emergence of new states and function in the course of a changing environment.« less
How Dark Are Radial Breathing Modes in Plasmonic Nanodisks?
2017-01-01
Due to a vanishing dipole moment, radial breathing modes in small flat plasmonic nanoparticles do not couple to light and have to be probed with a near-field source, as in electron energy loss spectroscopy (EELS). With increasing particle size, retardation gives rise to light coupling, enabling probing breathing modes optically or by cathodoluminescence (CL). Here, we investigate single silver nanodisks with diameters of 150–500 nm by EELS and CL in an electron microscope and quantify the EELS/CL ratio, which corresponds to the ratio of full to radiative damping of the breathing mode. For the investigated diameter range, we find the CL signal to increase by about 1 order of magnitude, in agreement with numerical simulations. Due to reciprocity, our findings corroborate former optical experiments and enable a quantitative understanding of the light coupling of dark plasmonic modes. PMID:29607350
Challenges to Superfund Community Nutrition Programs in Kentucky
Gaetke, Lisa; Gaetke, Kara; Bowen, Christa
2008-01-01
Since 2000, the University of Kentucky's (UK's) Superfund Basic Research Program (SBRP) Community Outreach Core has provided support and guidance through Superfund Community Action through Nutrition (SCAN) programs, which meet the needs of individuals and communities affected by environmental contaminants. It has been shown that nutrition may modulate the toxicity of Superfund chemicals. SCAN programs integrate nutrition education, nutrition science research, and health communication to increase understanding of health risks associated with residing near Superfund sites. Two critical tasks must be accomplished. SCAN personnel must identify and recruit affected community members, and then, offer meaningful programs. Certain quantitative outcome measures and legal issues presented both challenges and opportunities. Community members preferred qualitative evaluation discussions, which showed increased knowledge and improved attitudes following SCAN programs. SCAN, in full partnership with affected communities, translates safe, effective nutrition information to reduce health risks associated with exposure to Superfund pollutants. PMID:18443657
Challenges to superfund community nutrition programs in kentucky.
Gaetke, Lisa; Gaetke, Kara; Bowen, Christa
2008-03-01
Since 2000, the University of Kentucky's (UK's) Superfund Basic Research Program (SBRP) Community Outreach Core has provided support and guidance through Superfund Community Action through Nutrition (SCAN) programs, which meet the needs of individuals and communities affected by environmental contaminants. It has been shown that nutrition may modulate the toxicity of Superfund chemicals. SCAN programs integrate nutrition education, nutrition science research, and health communication to increase understanding of health risks associated with residing near Superfund sites. Two critical tasks must be accomplished. SCAN personnel must identify and recruit affected community members, and then, offer meaningful programs. Certain quantitative outcome measures and legal issues presented both challenges and opportunities. Community members preferred qualitative evaluation discussions, which showed increased knowledge and improved attitudes following SCAN programs. SCAN, in full partnership with affected communities, translates safe, effective nutrition information to reduce health risks associated with exposure to Superfund pollutants.
Coupling Processes between Atmospheric Chemistry and Climate
NASA Technical Reports Server (NTRS)
Ko, M. K. W.; Weisenstein, Debra; Shia, Run-Lie; Sze, N. D.
1998-01-01
This is the third semi-annual report for NAS5-97039, covering January through June 1998. The overall objective of this project is to improve the understanding of coupling processes between atmospheric chemistry and climate. Model predictions of the future distributions of trace gases in the atmosphere constitute an important component of the input necessary for quantitative assessments of global change. We will concentrate on the changes in ozone and stratospheric sulfate aerosol, with emphasis on how ozone in the lower stratosphere would respond to natural or anthropogenic changes. The key modeling for this work are the AER 2-dimensional chemistry-transport model, the AER 2-dimensional stratospheric sulfate model, and the AER three-wave interactive model with full chemistry. We will continue developing our three-wave model so that we can help NASA determine the strengths and weaknesses of the next generation assessment models.
Local Infrasound Variability Related to In Situ Atmospheric Observation
NASA Astrophysics Data System (ADS)
Kim, Keehoon; Rodgers, Arthur; Seastrand, Douglas
2018-04-01
Local infrasound is widely used to constrain source parameters of near-surface events (e.g., chemical explosions and volcanic eruptions). While atmospheric conditions are critical to infrasound propagation and source parameter inversion, local atmospheric variability is often ignored by assuming homogeneous atmospheres, and their impact on the source inversion uncertainty has never been accounted for due to the lack of quantitative understanding of infrasound variability. We investigate atmospheric impacts on local infrasound propagation by repeated explosion experiments with a dense acoustic network and in situ atmospheric measurement. We perform full 3-D waveform simulations with local atmospheric data and numerical weather forecast model to quantify atmosphere-dependent infrasound variability and address the advantage and restriction of local weather data/numerical weather model for sound propagation simulation. Numerical simulations with stochastic atmosphere models also showed nonnegligible influence of atmospheric heterogeneity on infrasound amplitude, suggesting an important role of local turbulence.
Psychological contracts: a new strategy for retaining reduced-hour physicians.
Hartwell, Jennifer K
2010-01-01
As a retention strategy, healthcare organizations offer reduced-hour schedules to physicians seeking better work-family balance. However, this quantitative study of 94 full-time and reduced-hour female physicians in the Boston area found that working fewer hours helps physicians achieve better balance but does not improve their burnout or career satisfaction, or impact their intention to quit or leave the field of medicine. Instead, the findings demonstrate that psychological contract fulfillment, which reflects the subjective nature of the employment relationship, is more important than work hours, an objective job condition, in predicting intention to quit and these other outcomes. A fine-grained analysis is initiated uncovering the multidimensionality of the psychological contract construct. To integrate successful reduced-hour arrangements for physicians, medical managers are directed to the importance of understanding the composition of reduced-hour physicians' psychological contracts, specifically, their need to do challenging work, receive high levels of supervisor support, and promotion opportunities.
Unified Time and Frequency Picture of Ultrafast Atomic Excitation in Strong Laser Fields
NASA Astrophysics Data System (ADS)
Zimmermann, H.; Patchkovskii, S.; Ivanov, M.; Eichmann, U.
2017-01-01
Excitation and ionization in strong laser fields lies at the heart of such diverse research directions as high-harmonic generation and spectroscopy, laser-induced diffraction imaging, emission of femtosecond electron bunches from nanotips, self-guiding, filamentation and mirrorless lasing during propagation of light in atmospheres. While extensive quantum mechanical and semiclassical calculations on strong-field ionization are well backed by sophisticated experiments, the existing scattered theoretical work aiming at a full quantitative understanding of strong-field excitation lacks experimental confirmation. Here we present experiments on strong-field excitation in both the tunneling and multiphoton regimes and their rigorous interpretation by time dependent Schrödinger equation calculations, which finally consolidates the seemingly opposing strong-field regimes with their complementary pictures. Most strikingly, we observe an unprecedented enhancement of excitation yields, which opens new possibilities in ultrafast strong-field control of Rydberg wave packet excitation and laser intensity characterization.
Magnetohydrodynamic Turbulence and the Geodynamo
NASA Technical Reports Server (NTRS)
Shebalin, John V.
2014-01-01
The ARES Directorate at JSC has researched the physical processes that create planetary magnetic fields through dynamo action since 2007. The "dynamo problem" has existed since 1600, when William Gilbert, physician to Queen Elizabeth I, recognized that the Earth was a giant magnet. In 1919, Joseph Larmor proposed that solar (and by implication, planetary) magnetism was due to magnetohydrodynamics (MHD), but full acceptance did not occur until Glatzmaier and Roberts solved the MHD equations numerically and simulated a geomagnetic reversal in 1995. JSC research produced a unique theoretical model in 2012 that provided a novel explanation of these physical observations and computational results as an essential manifestation of broken ergodicity in MHD turbulence. Research is ongoing, and future work is aimed at understanding quantitative details of magnetic dipole alignment in the Earth as well as in Mercury, Jupiter and its moon Ganymede, Saturn, Uranus, Neptune, and the Sun and other stars.
ERIC Educational Resources Information Center
Smeyers, Paul
2008-01-01
Generally educational research is grounded in the empirical traditions of the social sciences (commonly called quantitative and qualitative methods) and is as such distinguished from other forms of scholarship such as theoretical, conceptual or methodological essays, critiques of research traditions and practices and those studies grounded in the…
Educational Software for Mapping Quantitative Trait Loci (QTL)
ERIC Educational Resources Information Center
Helms, T. C.; Doetkott, C.
2007-01-01
This educational software was developed to aid teachers and students in their understanding of how the process of identifying the most likely quantitative trait loci (QTL) position is determined between two flanking DNA markers. The objective of the software that we developed was to: (1) show how a QTL is mapped to a position on a chromosome using…
Understanding the Use of Rural Space: The Need for Multi-Methods
ERIC Educational Resources Information Center
Madsen, Lene M.; Adriansen, Hanne Kirstine
2004-01-01
Although the late 1990s saw increasing use of qualitative data in rural studies and a turn towards issues such as identities and the construction of rurality, many rural researchers still rely on a range of different methods and use both qualitative and quantitative data. However, the challenge of combining quantitative and qualitative data and…
Patterns, Probabilities, and People: Making Sense of Quantitative Change in Complex Systems
ERIC Educational Resources Information Center
Wilkerson-Jerde, Michelle Hoda; Wilensky, Uri J.
2015-01-01
The learning sciences community has made significant progress in understanding how people think and learn about complex systems. But less is known about how people make sense of the quantitative patterns and mathematical formalisms often used to study these systems. In this article, we make a case for attending to and supporting connections…
Before new, rapid quantitative PCR (qPCR) methods for recreational water quality assessment and microbial source tracking (MST) can be useful in a regulatory context, an understanding of the ability of the method to detect a DNA target (marker) when the contaminant soure has been...
The Relationship between Stress, Coping Style, and Academic Satisfaction: A Quantitative Study
ERIC Educational Resources Information Center
Hodge-Windover, Sheila T.
2017-01-01
College students experience a great deal of stress, which is associated with poor health and poor levels of academic satisfaction which can lead to low retention. The purpose of this quantitative correlational study was to investigate how stress and coping style predict academic satisfaction and understand how and if coping style moderates the…
USDA-ARS?s Scientific Manuscript database
Wheat quality is defined by culinary end-uses and processing characteristics. Wheat breeders are interested to identify quantitative trait loci for grain, milling, and end-use quality traits because it is imperative to understand the genetic complexity underlying quantitatively inherited traits to ...
A Quantitative Content Analysis of Mercer University MEd, EdS, and Doctoral Theses
ERIC Educational Resources Information Center
Randolph, Justus J.; Gaiek, Lura S.; White, Torian A.; Slappey, Lisa A.; Chastain, Andrea; Harris, Rose Prejean
2010-01-01
Quantitative content analysis of a body of research not only helps budding researchers understand the culture, language, and expectations of scholarship, it helps identify deficiencies and inform policy and practice. Because of these benefits, an analysis of a census of 980 Mercer University MEd, EdS, and doctoral theses was conducted. Each thesis…
Mielczarek, A T; Saunders, A M; Larsen, P; Albertsen, M; Stevenson, M; Nielsen, J L; Nielsen, P H
2013-01-01
Since 2006 more than 50 Danish full-scale wastewater treatment plants with nutrient removal have been investigated in a project called 'The Microbial Database for Danish Activated Sludge Wastewater Treatment Plants with Nutrient Removal (MiDas-DK)'. Comprehensive sets of samples have been collected, analyzed and associated with extensive operational data from the plants. The community composition was analyzed by quantitative fluorescence in situ hybridization (FISH) supported by 16S rRNA amplicon sequencing and deep metagenomics. MiDas-DK has been a powerful tool to study the complex activated sludge ecosystems, and, besides many scientific articles on fundamental issues on mixed communities encompassing nitrifiers, denitrifiers, bacteria involved in P-removal, hydrolysis, fermentation, and foaming, the project has provided results that can be used to optimize the operation of full-scale plants and carry out trouble-shooting. A core microbial community has been defined comprising the majority of microorganisms present in the plants. Time series have been established, providing an overview of temporal variations in the different plants. Interestingly, although most microorganisms were present in all plants, there seemed to be plant-specific factors that controlled the population composition thereby keeping it unique in each plant over time. Statistical analyses of FISH and operational data revealed some correlations, but less than expected. MiDas-DK (www.midasdk.dk) will continue over the next years and we hope the approach can inspire others to make similar projects in other parts of the world to get a more comprehensive understanding of microbial communities in wastewater engineering.
Correlation of Oxygenated Hemoglobin Concentration and Psychophysical Amount on Speech Recognition
NASA Astrophysics Data System (ADS)
Nozawa, Akio; Ide, Hideto
The subjective understanding on oral language understanding task is quantitatively evaluated by the fluctuation of oxygenated hemoglobin concentration measured by the near-infrared spectroscopy. The English listening comprehension test wihch consists of two difficulty level was executed by 4 subjects during the measurement. A significant correlation was found between the subjective understanding and the fluctuation of oxygenated hemoglobin concentration.
Analysis of a document/reporting system
NASA Technical Reports Server (NTRS)
Narrow, B.
1971-01-01
An in-depth analysis of the information system within the Data Processing Branch is presented. Quantitative measures are used to evaluate the efficiency and effectiveness of the information system. It is believed that this is the first documented study which utilizes quantitative measures for full scale system analysis. The quantitative measures and techniques for collecting and qualifying the basic data, as described, are applicable to any information system. Therefore this report is considered to be of interest to any persons concerned with the management design, analysis or evaluation of information systems.
Glauser, Gaétan; Grund, Baptiste; Gassner, Anne-Laure; Menin, Laure; Henry, Hugues; Bromirski, Maciej; Schütz, Frédéric; McMullen, Justin; Rochat, Bertrand
2016-03-15
A paradigm shift is underway in the field of quantitative liquid chromatography-mass spectrometry (LC-MS) analysis thanks to the arrival of recent high-resolution mass spectrometers (HRMS). The capability of HRMS to perform sensitive and reliable quantifications of a large variety of analytes in HR-full scan mode is showing that it is now realistic to perform quantitative and qualitative analysis with the same instrument. Moreover, HR-full scan acquisition offers a global view of sample extracts and allows retrospective investigations as virtually all ionized compounds are detected with a high sensitivity. In time, the versatility of HRMS together with the increasing need for relative quantification of hundreds of endogenous metabolites should promote a shift from triple-quadrupole MS to HRMS. However, a current "pitfall" in quantitative LC-HRMS analysis is the lack of HRMS-specific guidance for validated quantitative analyses. Indeed, false positive and false negative HRMS detections are rare, albeit possible, if inadequate parameters are used. Here, we investigated two key parameters for the validation of LC-HRMS quantitative analyses: the mass accuracy (MA) and the mass-extraction-window (MEW) that is used to construct the extracted-ion-chromatograms. We propose MA-parameters, graphs, and equations to calculate rational MEW width for the validation of quantitative LC-HRMS methods. MA measurements were performed on four different LC-HRMS platforms. Experimentally determined MEW values ranged between 5.6 and 16.5 ppm and depended on the HRMS platform, its working environment, the calibration procedure, and the analyte considered. The proposed procedure provides a fit-for-purpose MEW determination and prevents false detections.
ERIC Educational Resources Information Center
Imler, Bonnie; Eichelberger, Michelle
2014-01-01
When asked to print the full text of an article, many undergraduate college students print the abstract instead of the full text. This study seeks to determine the underlying cause(s) of this confusion. In this quantitative study, participants (n = 40) performed five usability tasks to assess ease of use and usefulness of five commercial library…
Jung, Jae-Hwang; Jang, Jaeduck; Park, Yongkeun
2013-11-05
We present a novel spectroscopic quantitative phase imaging technique with a wavelength swept-source, referred to as swept-source diffraction phase microscopy (ssDPM), for quantifying the optical dispersion of microscopic individual samples. Employing the swept-source and the principle of common-path interferometry, ssDPM measures the multispectral full-field quantitative phase imaging and spectroscopic microrefractometry of transparent microscopic samples in the visible spectrum with a wavelength range of 450-750 nm and a spectral resolution of less than 8 nm. With unprecedented precision and sensitivity, we demonstrate the quantitative spectroscopic microrefractometry of individual polystyrene beads, 30% bovine serum albumin solution, and healthy human red blood cells.
Comments on "Understanding Graduate Women's Reentry Experiences." Commentary.
ERIC Educational Resources Information Center
Lott, Bernice
1999-01-01
The case-study method used in "Understanding Graduate Women's Reentry Experiences" yielded personal information of considerable depth, but the conclusions drawn from the study are not all that different from those drawn from more quantitative investigations. Suggests that a multimethod approach is the best research strategy. (SLD)
Understanding how and why different communities engage with sustainability policies and actions is of critical importance for furthering implementation of innovative and conventional sustainability strategies. Despite this importance, an understanding of how and why communities a...
Abstracts versus Full Texts and Patents: A Quantitative Analysis of Biomedical Entities
NASA Astrophysics Data System (ADS)
Müller, Bernd; Klinger, Roman; Gurulingappa, Harsha; Mevissen, Heinz-Theodor; Hofmann-Apitius, Martin; Fluck, Juliane; Friedrich, Christoph M.
In information retrieval, named entity recognition gives the opportunity to apply semantic search in domain specific corpora. Recently, more full text patents and journal articles became freely available. As the information distribution amongst the different sections is unknown, an analysis of the diversity is of interest.
Using PAT to accelerate the transition to continuous API manufacturing.
Gouveia, Francisca F; Rahbek, Jesper P; Mortensen, Asmus R; Pedersen, Mette T; Felizardo, Pedro M; Bro, Rasmus; Mealy, Michael J
2017-01-01
Significant improvements can be realized by converting conventional batch processes into continuous ones. The main drivers include reduction of cost and waste, increased safety, and simpler scale-up and tech transfer activities. Re-designing the process layout offers the opportunity to incorporate a set of process analytical technologies (PAT) embraced in the Quality-by-Design (QbD) framework. These tools are used for process state estimation, providing enhanced understanding of the underlying variability in the process impacting quality and yield. This work describes a road map for identifying the best technology to speed-up the development of continuous processes while providing the basis for developing analytical methods for monitoring and controlling the continuous full-scale reaction. The suitability of in-line Raman, FT-infrared (FT-IR), and near-infrared (NIR) spectroscopy for real-time process monitoring was investigated in the production of 1-bromo-2-iodobenzene. The synthesis consists of three consecutive reaction steps including the formation of an unstable diazonium salt intermediate, which is critical to secure high yield and avoid formation of by-products. All spectroscopic methods were able to capture critical information related to the accumulation of the intermediate with very similar accuracy. NIR spectroscopy proved to be satisfactory in terms of performance, ease of installation, full-scale transferability, and stability to very adverse process conditions. As such, in-line NIR was selected to monitor the continuous full-scale production. The quantitative method was developed against theoretical concentration values of the intermediate since representative sampling for off-line reference analysis cannot be achieved. The rapid and reliable analytical system allowed the following: speeding up the design of the continuous process and a better understanding of the manufacturing requirements to ensure optimal yield and avoid unreacted raw materials and by-products in the continuous reactor effluent. Graphical Abstract Using PAT to accelerate the transition to continuous API manufacturing.
Murray, Peter D; Dobbels, Fabienne; Lonsdale, Daniel C; Harden, Paul N
2014-10-01
Young adult kidney patients are at an important stage of development when end-stage kidney disease (ESKD) may adversely influence progress in education and employment. This study is designed to assess the impact of ESKD on education and employment outcomes in young adults. This cross-sectional study was a mixed methods design. Education and career achievements in young adults with ESKD were recorded quantitatively using a questionnaire survey (n = 57): 14 of 57 representative participants were subsequently selected for semistructured interview. Questionnaire survey was conducted in 57 young adults (median age 25): 8.8% (n = 5) were predialysis; 14.0% (n = 8) dialysis; and 78.9% (n = 45) were kidney transplant recipients. Median school-leaving age was 16 (interquartile range = 15-19). Of 57 young adults, 10 (17.5%) were still studying, 43 (75.4%) had completed education, 34 (59.7%) were employed (23 full time and 11 part time), and 19 (33.3%) were unemployed. Twenty-seven of 45 transplanted patients were employed (60.0%). Of these 27, 21 were full time (77.8%). Five of eight dialysis patients were employed: only one of eight was full-time employed (12.5%). Themes impacting on education and employment included low energy levels, time missed, loss of self-esteem, and feelings of loneliness and isolation, which may progress to depression and recreational drug use. Lack of understanding from educators and employers resulting in lost work, and career ambitions changed or limited because of dialysis. Dialysis has a major negative impact on education and reduced employment rates of young adults. There is a general lack of understanding among educators and employers of the impact of ESKD. Low energy levels, lack of self-esteem, and depression are key factors. There is a need for health care providers to recognize this issue and invest in supporting young adults with ESKD. Copyright © 2014 Society for Adolescent Health and Medicine. Published by Elsevier Inc. All rights reserved.
Westergaard, David; Stærfeldt, Hans-Henrik; Tønsberg, Christian; Jensen, Lars Juhl; Brunak, Søren
2018-02-01
Across academia and industry, text mining has become a popular strategy for keeping up with the rapid growth of the scientific literature. Text mining of the scientific literature has mostly been carried out on collections of abstracts, due to their availability. Here we present an analysis of 15 million English scientific full-text articles published during the period 1823-2016. We describe the development in article length and publication sub-topics during these nearly 250 years. We showcase the potential of text mining by extracting published protein-protein, disease-gene, and protein subcellular associations using a named entity recognition system, and quantitatively report on their accuracy using gold standard benchmark data sets. We subsequently compare the findings to corresponding results obtained on 16.5 million abstracts included in MEDLINE and show that text mining of full-text articles consistently outperforms using abstracts only.
Westergaard, David; Stærfeldt, Hans-Henrik
2018-01-01
Across academia and industry, text mining has become a popular strategy for keeping up with the rapid growth of the scientific literature. Text mining of the scientific literature has mostly been carried out on collections of abstracts, due to their availability. Here we present an analysis of 15 million English scientific full-text articles published during the period 1823–2016. We describe the development in article length and publication sub-topics during these nearly 250 years. We showcase the potential of text mining by extracting published protein–protein, disease–gene, and protein subcellular associations using a named entity recognition system, and quantitatively report on their accuracy using gold standard benchmark data sets. We subsequently compare the findings to corresponding results obtained on 16.5 million abstracts included in MEDLINE and show that text mining of full-text articles consistently outperforms using abstracts only. PMID:29447159
Narayanaswamy, Bhavani E.
2013-01-01
The recently completed European Census of Marine Life, conducted within the framework of the global Census of Marine Life programme (2000–2010), markedly enhanced our understanding of marine biodiversity in European Seas, its importance within ecological systems, and the implications for human use. Here we undertake a synthesis of present knowledge of biodiversity in European Seas and identify remaining challenges that prevent sustainable management of marine biodiversity in one of the most exploited continents of the globe. Our analysis demonstrates that changes in faunal standing stock with depth depends on the size of the fauna, with macrofaunal abundance only declining with increasing water depth below 1000 m, whilst there was no obvious decrease in meiofauna with increasing depth. Species richness was highly variable for both deep water macro- and meio- fauna along latitudinal and longitudinal gradients. Nematode biodiversity decreased from the Atlantic into the Mediterranean whilst latitudinal related biodiversity patterns were similar for both faunal groups investigated, suggesting that the same environmental drivers were influencing the fauna. While climate change and habitat degradation are the most frequently implicated stressors affecting biodiversity throughout European Seas, quantitative understanding, both at individual and cumulative/synergistic level, of their influences are often lacking. Full identification and quantification of species, in even a single marine habitat, remains a distant goal, as we lack integrated data-sets to quantify these. While the importance of safeguarding marine biodiversity is recognised by policy makers, the lack of advanced understanding of species diversity and of a full survey of any single habitat raises huge challenges in quantifying change, and facilitating/prioritising habitat/ecosystem protection. Our study highlights a pressing requirement for more complete biodiversity surveys to be undertaken within contrasting habitats, together with investigations in biodiversity-ecosystem functioning links and identification of separate and synergistic/cumulative human-induced impacts on biodiversity. PMID:23527045
Narayanaswamy, Bhavani E; Coll, Marta; Danovaro, Roberto; Davidson, Keith; Ojaveer, Henn; Renaud, Paul E
2013-01-01
The recently completed European Census of Marine Life, conducted within the framework of the global Census of Marine Life programme (2000-2010), markedly enhanced our understanding of marine biodiversity in European Seas, its importance within ecological systems, and the implications for human use. Here we undertake a synthesis of present knowledge of biodiversity in European Seas and identify remaining challenges that prevent sustainable management of marine biodiversity in one of the most exploited continents of the globe. Our analysis demonstrates that changes in faunal standing stock with depth depends on the size of the fauna, with macrofaunal abundance only declining with increasing water depth below 1000 m, whilst there was no obvious decrease in meiofauna with increasing depth. Species richness was highly variable for both deep water macro- and meio- fauna along latitudinal and longitudinal gradients. Nematode biodiversity decreased from the Atlantic into the Mediterranean whilst latitudinal related biodiversity patterns were similar for both faunal groups investigated, suggesting that the same environmental drivers were influencing the fauna. While climate change and habitat degradation are the most frequently implicated stressors affecting biodiversity throughout European Seas, quantitative understanding, both at individual and cumulative/synergistic level, of their influences are often lacking. Full identification and quantification of species, in even a single marine habitat, remains a distant goal, as we lack integrated data-sets to quantify these. While the importance of safeguarding marine biodiversity is recognised by policy makers, the lack of advanced understanding of species diversity and of a full survey of any single habitat raises huge challenges in quantifying change, and facilitating/prioritising habitat/ecosystem protection. Our study highlights a pressing requirement for more complete biodiversity surveys to be undertaken within contrasting habitats, together with investigations in biodiversity-ecosystem functioning links and identification of separate and synergistic/cumulative human-induced impacts on biodiversity.
ERIC Educational Resources Information Center
Belue, Paul T.; Cavey, Laurie Overman; Kinzel, Margaret T.
2017-01-01
In this exploratory study, we examined the effects of a quantitative reasoning instructional approach to linear equations in two variables on community college students' conceptual understanding, procedural fluency, and reasoning ability. This was done in comparison to the use of a traditional procedural approach for instruction on the same topic.…
ERIC Educational Resources Information Center
Finch, Lauren E.; Hillyer, Margot M.; Leopold, Michael C.
2015-01-01
For most chemistry curricula, laboratory-based activities in quantitative and instrumental analysis continue to be an important aspect of student development/training, one that can be more effective if conceptual understanding is delivered through an inquiry-based process relating the material to relevant issues of public interest and student…
ERIC Educational Resources Information Center
Fry, Charles G.; Hofstetter, Heike; Bowman, Matthew D.
2017-01-01
Quantitative [superscript 13]C NMR provides a straightforward method of analyzing edible oils in undergraduate chemistry laboratories. [superscript 13]C spectra are relatively easy to understand, and are much simpler to analyze and workup than corresponding [superscript 1]H spectra. Average chain length, degree of saturation, and average…
Ezard, Thomas H.G.; Jørgensen, Peter S.; Zimmerman, Naupaka; Chamberlain, Scott; Salguero-Gómez, Roberto; Curran, Timothy J.; Poisot, Timothée
2014-01-01
Proficiency in mathematics and statistics is essential to modern ecological science, yet few studies have assessed the level of quantitative training received by ecologists. To do so, we conducted an online survey. The 937 respondents were mostly early-career scientists who studied biology as undergraduates. We found a clear self-perceived lack of quantitative training: 75% were not satisfied with their understanding of mathematical models; 75% felt that the level of mathematics was “too low” in their ecology classes; 90% wanted more mathematics classes for ecologists; and 95% more statistics classes. Respondents thought that 30% of classes in ecology-related degrees should be focused on quantitative disciplines, which is likely higher than for most existing programs. The main suggestion to improve quantitative training was to relate theoretical and statistical modeling to applied ecological problems. Improving quantitative training will require dedicated, quantitative classes for ecology-related degrees that contain good mathematical and statistical practice. PMID:24688862
Yoshikawa, Hirokazu; Weisner, Thomas S; Kalil, Ariel; Way, Niobe
2008-03-01
Multiple methods are vital to understanding development as a dynamic, transactional process. This article focuses on the ways in which quantitative and qualitative methodologies can be combined to enrich developmental science and the study of human development, focusing on the practical questions of "when" and "how." Research situations that may be especially suited to mixing qualitative and quantitative approaches are described. The authors also discuss potential choices for using mixed quantitative- qualitative approaches in study design, sampling, construction of measures or interview protocols, collaborations, and data analysis relevant to developmental science. Finally, they discuss some common pitfalls that occur in mixing these methods and include suggestions for surmounting them.
Energy Education: The Quantitative Voice
NASA Astrophysics Data System (ADS)
Wolfson, Richard
2010-02-01
A serious study of energy use and its consequences has to be quantitative. It makes little sense to push your favorite renewable energy source if it can't provide enough energy to make a dent in humankind's prodigious energy consumption. Conversely, it makes no sense to dismiss alternatives---solar in particular---that supply Earth with energy at some 10,000 times our human energy consumption rate. But being quantitative---especially with nonscience students or the general public---is a delicate business. This talk draws on the speaker's experience presenting energy issues to diverse audiences through single lectures, entire courses, and a textbook. The emphasis is on developing a quick, ``back-of-the-envelope'' approach to quantitative understanding of energy issues. )
Leung, Janet T Y; Shek, Daniel T L
2011-01-01
This paper examines the use of quantitative and qualitative approaches to study the impact of economic disadvantage on family processes and adolescent development. Quantitative research has the merits of objectivity, good predictive and explanatory power, parsimony, precision and sophistication of analysis. Qualitative research, in contrast, provides a detailed, holistic, in-depth understanding of social reality and allows illumination of new insights. With the pragmatic considerations of methodological appropriateness, design flexibility, and situational responsiveness in responding to the research inquiry, a mixed methods approach could be a possibility of integrating quantitative and qualitative approaches and offers an alternative strategy to study the impact of economic disadvantage on family processes and adolescent development.
Pepin, K.M.; Spackman, E.; Brown, J.D.; Pabilonia, K.L.; Garber, L.P.; Weaver, J.T.; Kennedy, D.A.; Patyk, K.A.; Huyvaert, K.P.; Miller, R.S.; Franklin, A.B.; Pedersen, K.; Bogich, T.L.; Rohani, P.; Shriner, S.A.; Webb, C.T.; Riley, S.
2014-01-01
Wild birds are the primary source of genetic diversity for influenza A viruses that eventually emerge in poultry and humans. Much progress has been made in the descriptive ecology of avian influenza viruses (AIVs), but contributions are less evident from quantitative studies (e.g., those including disease dynamic models). Transmission between host species, individuals and flocks has not been measured with sufficient accuracy to allow robust quantitative evaluation of alternate control protocols. We focused on the United States of America (USA) as a case study for determining the state of our quantitative knowledge of potential AIV emergence processes from wild hosts to poultry. We identified priorities for quantitative research that would build on existing tools for responding to AIV in poultry and concluded that the following knowledge gaps can be addressed with current empirical data: (1) quantification of the spatio-temporal relationships between AIV prevalence in wild hosts and poultry populations, (2) understanding how the structure of different poultry sectors impacts within-flock transmission, (3) determining mechanisms and rates of between-farm spread, and (4) validating current policy-decision tools with data. The modeling studies we recommend will improve our mechanistic understanding of potential AIV transmission patterns in USA poultry, leading to improved measures of accuracy and reduced uncertainty when evaluating alternative control strategies. PMID:24462191
NASA Astrophysics Data System (ADS)
Gan, Yanjun; Liang, Xin-Zhong; Duan, Qingyun; Choi, Hyun Il; Dai, Yongjiu; Wu, Huan
2015-06-01
An uncertainty quantification framework was employed to examine the sensitivities of 24 model parameters from a newly developed Conjunctive Surface-Subsurface Process (CSSP) land surface model (LSM). The sensitivity analysis (SA) was performed over 18 representative watersheds in the contiguous United States to examine the influence of model parameters in the simulation of terrestrial hydrological processes. Two normalized metrics, relative bias (RB) and Nash-Sutcliffe efficiency (NSE), were adopted to assess the fit between simulated and observed streamflow discharge (SD) and evapotranspiration (ET) for a 14 year period. SA was conducted using a multiobjective two-stage approach, in which the first stage was a qualitative SA using the Latin Hypercube-based One-At-a-Time (LH-OAT) screening, and the second stage was a quantitative SA using the Multivariate Adaptive Regression Splines (MARS)-based Sobol' sensitivity indices. This approach combines the merits of qualitative and quantitative global SA methods, and is effective and efficient for understanding and simplifying large, complex system models. Ten of the 24 parameters were identified as important across different watersheds. The contribution of each parameter to the total response variance was then quantified by Sobol' sensitivity indices. Generally, parameter interactions contribute the most to the response variance of the CSSP, and only 5 out of 24 parameters dominate model behavior. Four photosynthetic and respiratory parameters are shown to be influential to ET, whereas reference depth for saturated hydraulic conductivity is the most influential parameter for SD in most watersheds. Parameter sensitivity patterns mainly depend on hydroclimatic regime, as well as vegetation type and soil texture. This article was corrected on 26 JUN 2015. See the end of the full text for details.
Whear, Rebecca; Coon, Jo Thompson; Bethel, Alison; Abbott, Rebecca; Stein, Ken; Garside, Ruth
2014-10-01
To examine the impact of gardens and outdoor spaces on the mental and physical well-being of people with dementia who are resident in care homes and understand the views of people with dementia, their carers, and care home staff on the value of gardens and outdoor spaces. Systematic review. Fourteen databases were searched from inception to February 2013. Forward and backward citation chasing of included articles was conducted; 38 relevant organizations were contacted to identify unpublished reports. Titles, abstracts, and full texts were screened independently by 2 reviewers in a 2-stage process and were discussed with a third reviewer where necessary. Results were synthesized narratively. Seventeen studies were included: 9 quantitative, 7 qualitative, and 1 mixed methods. The quantitative studies were of poor quality but suggested decreased levels of agitation were associated with garden use. The views and experiences of the garden are discussed in relation to themes of how the garden was used, nature of interactions, impact/effect of the gardens, mechanisms/how the garden was thought to have an effect, and negatives (such as perception of the garden as a hazard and the limited staff time). There are promising impacts on levels of agitation in care home residents with dementia who spend time in a garden. Future research would benefit from a focus on key outcomes measured in comparable ways with a separate focus on what lies behind limited accessibility to gardens within the residential care setting. Copyright © 2014 AMDA – The Society for Post-Acute and Long-Term Care Medicine. Published by Elsevier Inc. All rights reserved.
ERIC Educational Resources Information Center
Huerta, Margarita; Tong, Fuhui; Irby, Beverly J.; Lara-Alecio, Rafael
2016-01-01
The authors of this quantitative study measured and compared the academic language development and conceptual understanding of fifth-grade economically disadvantaged English language learners (ELL), former ELLs, and native English-speaking (ES) students as reflected in their science notebook scores. Using an instrument they developed, the authors…
A Qualitative Approach to Understanding Audience's Perceptions of Creativity in Online Advertising
ERIC Educational Resources Information Center
McStay, Andrew
2010-01-01
In this paper I seek to inquire upon audience's perceptions of creativity in online advertising--a heretofore poorly understood area. This paper initially outlines current academic understanding of creativity in online advertising, mainly derived from quantitative assessments. It then advances a qualitative methodology including diary-interviews…
Using Algorithms in Solving Synapse Transmission Problems.
ERIC Educational Resources Information Center
Stencel, John E.
1992-01-01
Explains how a simple three-step algorithm can aid college students in solving synapse transmission problems. Reports that all of the students did not completely understand the algorithm. However, many learn a simple working model of synaptic transmission and understand why an impulse will pass across a synapse quantitatively. Students also see…
Advanced Quantitative Measurement Methodology in Physics Education Research
ERIC Educational Resources Information Center
Wang, Jing
2009-01-01
The ultimate goal of physics education research (PER) is to develop a theoretical framework to understand and improve the learning process. In this journey of discovery, assessment serves as our headlamp and alpenstock. It sometimes detects signals in student mental structures, and sometimes presents the difference between expert understanding and…
Cooperative Bacterial Growth Dynamics Predict the Evolution of Antibiotic Resistance
NASA Astrophysics Data System (ADS)
Artemova, Tatiana; Gerardin, Ylaine; Hsin-Jung Li, Sophia; Gore, Jeff
2011-03-01
Since the discovery of penicillin, antibiotics have been our primary weapon against bacterial infections. Unfortunately, bacteria can gain resistance to penicillin by acquiring the gene that encodes beta-lactamase, which inactivates the antibiotic. However, mutations in this gene are necessary to degrade the modern antibiotic cefotaxime. Understanding the conditions that favor the spread of these mutations is a challenge. Here we show that bacterial growth in beta-lactam antibiotics is cooperative and that the nature of this growth determines the conditions in which resistance evolves. Quantitative analysis of the growth dynamics predicts a peak in selection at very low antibiotic concentrations; competition between strains confirms this prediction. We also find significant selection at higher antibiotic concentrations, close to the minimum inhibitory concentrations of the strains. Our results argue that an understanding of the evolutionary forces that lead to antibiotic resistance requires a quantitative understanding of the evolution of cooperation in bacteria.
Distributed Stress Sensing and Non-Destructive Tests Using Mechanoluminescence Materials
NASA Astrophysics Data System (ADS)
Rahimi, Mohammad Reza
Rapid aging of infrastructure systems is currently pervasive in the US and the anticipated cost until 2020 for rehabilitation of aging lifeline will reach 3.6 trillion US dollars (ASCE 2013). Reliable condition or serviceability assessment is critically important in decision-making for economic and timely maintenance of the infrastructure systems. Advanced sensors and nondestructive test (NDT) methods are the key technologies for structural health monitoring (SHM) applications that can provide information on the current state of structures. There are many traditional sensors and NDT methods, for examples, strain gauges, ultrasound, radiography and other X-ray, etc. to detect any defect on the infrastructure. Considering that civil infrastructure is typically large-scale and exhibits complex behavior, estimation of structural conditions by the local sensing and NDT methods is a challenging task. Non-contact and distributed (or full-field) sensing and NDT method are desirable that can provide rich information on the civil infrastructure's state. Materials with the ability of emitting light, especially in the visible range, are named as luminescent materials. Mechanoluminescence (ML) phenomenon is the light emission from luminescent materials as a response of an induced mechanical stress. ML materials offer new opportunities for SHM that can directly visualize the stress and crack distributions on the surface of structures through ML light emission. Although material research for ML phenomena have been made substantially, applications of the ML sensors to full-field stress and crack visualization are still at infant stage and have yet to be full-fledged. Moreover, practical applications of the ML sensors for SHM of civil infrastructure have difficulties since numerous challenging problems (e.g. environmental effect) arise in actual applications. In order to realize a practical SHM system employing ML sensors, more research needs to be conducted, for examples, fundamental understandings of physics of ML phenomenon, method for quantitative stress measurements, calibration method for ML sensors, improvement of sensitivity, optimal manufacturing and design of ML sensors, environmental effects of ML phenomenon (e.g. temperature), image processing and analysis, etc. In this research, fundamental ML phenomena of two most promising ML sensing materials were experimentally studied and a methodology for full-field quantitative strain measurements, for the first time, was proposed along with a standardized calibration method. Characteristics and behavior of ML composites and thin films coated on the structure have been studied under various material tests including compression, tension, pure shear, bending, etc. In addition, ML emission sensitivity to the manufacturing parameters and experimental conditions was addressed in order to find optimal design the ML sensor. A phenomenological stress-optics transduction model for predicting the ML light intensity from a thin-film ML coating sensor subjected to in-plane stresses was proposed. A new full-field quantitative strain measuring methodology by ML thin film sensor was developed, for the first time, in order to visualize and measure the strain field. The results from the ML sensor were compared and verified by finite element simulation results. For NDT applications of ML sensors, experimental tests were conducted to visualize the cracks on structural surfaces and detect damages on structural components. In summary, this research proposes and realizes a new distributed stress sensor and NDT method using ML sensing materials. The proposed method is experimentally validated to be effective for stress measurement and crack visualizations. Successful completion of this research provides a leap toward a commercial light intensity-based optic sensor to be used as a new full-field stress measurement technology and NDT method.
JPEG2000 vs. full frame wavelet packet compression for smart card medical records.
Leehan, Joaquín Azpirox; Lerallut, Jean-Francois
2006-01-01
This paper describes a comparison among different compression methods to be used in the context of electronic health records in the newer version of "smart cards". The JPEG2000 standard is compared to a full-frame wavelet packet compression method at high (33:1 and 50:1) compression rates. Results show that the full-frame method outperforms the JPEG2K standard qualitatively and quantitatively.
Human systems immunology: hypothesis-based modeling and unbiased data-driven approaches.
Arazi, Arnon; Pendergraft, William F; Ribeiro, Ruy M; Perelson, Alan S; Hacohen, Nir
2013-10-31
Systems immunology is an emerging paradigm that aims at a more systematic and quantitative understanding of the immune system. Two major approaches have been utilized to date in this field: unbiased data-driven modeling to comprehensively identify molecular and cellular components of a system and their interactions; and hypothesis-based quantitative modeling to understand the operating principles of a system by extracting a minimal set of variables and rules underlying them. In this review, we describe applications of the two approaches to the study of viral infections and autoimmune diseases in humans, and discuss possible ways by which these two approaches can synergize when applied to human immunology. Copyright © 2012 Elsevier Ltd. All rights reserved.
Venkatakrishnan, K; Friberg, L E; Ouellet, D; Mettetal, J T; Stein, A; Trocóniz, I F; Bruno, R; Mehrotra, N; Gobburu, J; Mould, D R
2015-01-01
Despite advances in biomedical research that have deepened our understanding of cancer hallmarks, resulting in the discovery and development of targeted therapies, the success rates of oncology drug development remain low. Opportunities remain for objective dose selection informed by exposure-response understanding to optimize the benefit-risk balance of novel therapies for cancer patients. This review article discusses the principles and applications of modeling and simulation approaches across the lifecycle of development of oncology therapeutics. Illustrative examples are used to convey the value gained from integration of quantitative clinical pharmacology strategies from the preclinical-translational phase through confirmatory clinical evaluation of efficacy and safety. © 2014 American Society for Clinical Pharmacology and Therapeutics.
Yuan, Fu-song; Sun, Yu-chun; Xie, Xiao-yan; Wang, Yong; Lv, Pei-jun
2013-12-18
To quantitatively evaluate the artifacts appearance of eight kinds of common dental restorative materials, such as zirconia. For the full-crown tooth preparation of mandibular first molar, eight kinds of full-crowns, such as zirconia all-ceramic crown, glass ceramic crown, ceramage crown, Au-Pt based porcelain-fused-metal (PFM) crown, Pure Titanium PFM crown, Co-Cr PFM crown, Ni-Cr PFM crown, and Au-Pd metal crown were fabricated. And natural teeth in vitro were used as controls. These full-crown and natural teeth in vitro were mounted an ultraviolet-curable resin fixed plate. High resolution cone beam computed tomography (CBCT) was used to scan all of the crowns and natural teeth in vitro, and their DICOM data were imported into software MIMICS 10.0. Then, the number of stripes and the maximum diameters of artifacts around the full-crowns were evaluated quantitatively in two-dimensional tomography images. In the two-dimensional tomography images,the artifacts did not appear around the natural teeth in vitro, glass ceramic crown, and ceramage crown. But thr artifacts appeared around the zirconia all-ceramic and metal crown. The number of stripes of artifacts was five to nine per one crown. The maximum diameters of the artifacts were 2.4 to 2.6 cm and 2.2 to 2.7 cm. In the two-dimensional tomography images of CBCT, stripe-like and radical artifacts were caused around the zirconia all-ceramic crown and metal based porcelain-fused-metal crowns. These artifacts could lower the imaging quality of the full crown shape greatly. The artifact was not caused around the natural teeth in vitro, glass ceramic crown, and ceramage crown.
NASA Astrophysics Data System (ADS)
Shuang, Chen; Tie, Su; Yao-Bang, Zheng; Li, Chen; Ting-Xu, Liu; Ren-Bing, Li; Fu-Rong, Yang
2016-06-01
The aim of the present work is to quantitatively measure the hydroxyl radical concentration by using LIF (laser-induced fluorescence) in flame. The detailed physical models of spectral absorption lineshape broadening, collisional transition and quenching at elevated pressure are built. The fine energy level structure of the OH molecule is illustrated to understand the process with laser-induced fluorescence emission and others in the case without radiation, which include collisional quenching, rotational energy transfer (RET), and vibrational energy transfer (VET). Based on these, some numerical results are achieved by simulations in order to evaluate the fluorescence yield at elevated pressure. These results are useful for understanding the real physical processes in OH-LIF technique and finding a way to calibrate the signal for quantitative measurement of OH concentration in a practical combustor. Project supported by the National Natural Science Foundation of China (Grant No. 11272338) and the Fund from the Science and Technology on Scramjet Key Laboratory, China (Grant No. STSKFKT2013004).
NASA Astrophysics Data System (ADS)
Wang, Hui; Wang, Jian-Tao; Cao, Ze-Xian; Zhang, Wen-Jun; Lee, Chun-Sing; Lee, Shuit-Tong; Zhang, Xiao-Hong
2015-03-01
While the vapour-liquid-solid process has been widely used for growing one-dimensional nanostructures, quantitative understanding of the process is still far from adequate. For example, the origins for the growth of periodic one-dimensional nanostructures are not fully understood. Here we observe that morphologies in a wide range of periodic one-dimensional nanostructures can be described by two quantitative relationships: first, inverse of the periodic spacing along the length direction follows an arithmetic sequence; second, the periodic spacing in the growth direction varies linearly with the diameter of the nanostructure. We further find that these geometric relationships can be explained by considering the surface curvature oscillation of the liquid sphere at the tip of the growing nanostructure. The work reveals the requirements of vapour-liquid-solid growth. It can be applied for quantitative understanding of vapour-liquid-solid growth and to design experiments for controlled growth of nanostructures with custom-designed morphologies.
MECHANICS OF THE LUNG IN THE 20TH CENTURY
Mitzner, Wayne
2015-01-01
Major advances in respiratory mechanics occurred primarily in the latter half of the 20th century, and this is when much of our current understanding was secured. The earliest and ancient investigations involving respiratory physiology and mechanics were often done in conjunction with other scientific activities and often lacked the ability to make quantitative measurements. This situation changed rapidly in the 20th century, and this relatively recent history of lung mechanics has been greatly influenced by critical technological advances and applications, which have made quantitative experimental testing of ideas possible. From the spirometer of Hutchinson, to the pneumotachograph of Fleisch, to the measurement of esophageal pressure, to the use of the Wilhelmy balance by Clements, to the unassuming strain gauges for measuring pressure and rapid paper and electronic chart recorders, these enabling devices have generated numerous quantitative experimental studies with greatly increased physiologic understanding and validation of mechanistic theories of lung function in health and disease. PMID:23733695
NASA Astrophysics Data System (ADS)
Böttger, B.; Apel, M.; Santillana, B.; Eskin, D. G.
2013-08-01
Hot cracking is one of the major defects in continuous casting of steels, frequently limiting the productivity. To understand the factors leading to this defect, microstructure formation is simulated for a low-carbon and two high-strength low-alloyed steels. 2D simulation of the initial stage of solidification is performed in a moving slice of the slab using proprietary multiphase-field software and taking into account all elements which are expected to have a relevant effect on the mechanical properties and structure formation during solidification. To account for the correct thermodynamic and kinetic properties of the multicomponent alloy grades, the simulation software is online coupled to commercial thermodynamic and mobility databases. A moving-frame boundary condition allows traveling through the entire solidification history starting from the slab surface, and tracking the morphology changes during growth of the shell. From the simulation results, significant microstructure differences between the steel grades are quantitatively evaluated and correlated with their hot cracking behavior according to the Rappaz-Drezet-Gremaud (RDG) hot cracking criterion. The possible role of the microalloying elements in hot cracking, in particular of traces of Ti, is analyzed. With the assumption that TiN precipitates trigger coalescence of the primary dendrites, quantitative evaluation of the critical strain rates leads to a full agreement with the observed hot cracking behavior.
Zhu, Xin-Guang; Lynch, Jonathan P; LeBauer, David S; Millar, Andrew J; Stitt, Mark; Long, Stephen P
2016-05-01
A paradigm shift is needed and timely in moving plant modelling from largely isolated efforts to a connected community endeavour that can take full advantage of advances in computer science and in mechanistic understanding of plant processes. Plants in silico (Psi) envisions a digital representation of layered dynamic modules, linking from gene networks and metabolic pathways through to cellular organization, tissue, organ and whole plant development, together with resource capture and use efficiency in dynamic competitive environments, ultimately allowing a mechanistically rich simulation of the plant or of a community of plants in silico. The concept is to integrate models or modules from different layers of organization spanning from genome to phenome to ecosystem in a modular framework allowing the use of modules of varying mechanistic detail representing the same biological process. Developments in high-performance computing, functional knowledge of plants, the internet and open-source version controlled software make achieving the concept realistic. Open source will enhance collaboration and move towards testing and consensus on quantitative theoretical frameworks. Importantly, Psi provides a quantitative knowledge framework where the implications of a discovery at one level, for example, single gene function or developmental response, can be examined at the whole plant or even crop and natural ecosystem levels. © 2015 The Authors Plant, Cell & Environment Published by John Wiley & Sons Ltd.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Monteforte, Marianne; Estandarte, Ana K.; Chen, Bo
2016-06-23
High-energy X-ray Bragg coherent diffraction imaging (BCDI) is a well established synchrotron-based technique used to quantitatively reconstruct the three-dimensional morphology and strain distribution in nanocrystals. The BCDI technique has become a powerful analytical tool for quantitative investigations of nanocrystals, nanotubes, nanorods and more recently biological systems. BCDI has however typically failed for fine nanocrystals in sub-100?nm size regimes ? a size routinely achievable by chemical synthesis ? despite the spatial resolution of the BCDI technique being 20?30?nm. The limitations of this technique arise from the movement of nanocrystals under illumination by the highly coherent beam, which prevents full diffraction datamore » sets from being acquired. A solution is provided here to overcome this problem and extend the size limit of the BCDI technique, through the design of a novel stabilization method by embedding the fine nanocrystals into a silica matrix. Chemically synthesized FePt nanocrystals of maximum dimension 20?nm and AuPd nanocrystals in the size range 60?65?nm were investigated with BCDI measurement at beamline 34-ID-C of the APS, Argonne National Laboratory. Novel experimental methodologies to elucidate the presence of strain in fine nanocrystals are a necessary pre-requisite in order to better understand strain profiles in engineered nanocrystals for novel device development.« less
Monteforte, Marianne; Estandarte, Ana K; Chen, Bo; Harder, Ross; Huang, Michael H; Robinson, Ian K
2016-07-01
High-energy X-ray Bragg coherent diffraction imaging (BCDI) is a well established synchrotron-based technique used to quantitatively reconstruct the three-dimensional morphology and strain distribution in nanocrystals. The BCDI technique has become a powerful analytical tool for quantitative investigations of nanocrystals, nanotubes, nanorods and more recently biological systems. BCDI has however typically failed for fine nanocrystals in sub-100 nm size regimes - a size routinely achievable by chemical synthesis - despite the spatial resolution of the BCDI technique being 20-30 nm. The limitations of this technique arise from the movement of nanocrystals under illumination by the highly coherent beam, which prevents full diffraction data sets from being acquired. A solution is provided here to overcome this problem and extend the size limit of the BCDI technique, through the design of a novel stabilization method by embedding the fine nanocrystals into a silica matrix. Chemically synthesized FePt nanocrystals of maximum dimension 20 nm and AuPd nanocrystals in the size range 60-65 nm were investigated with BCDI measurement at beamline 34-ID-C of the APS, Argonne National Laboratory. Novel experimental methodologies to elucidate the presence of strain in fine nanocrystals are a necessary pre-requisite in order to better understand strain profiles in engineered nanocrystals for novel device development.
Application of Neutron Tomography in Culture Heritage research.
Mongy, T
2014-02-01
Neutron Tomography (NT) investigation of Culture Heritages (CH) is an efficient tool for understanding the culture of ancient civilizations. Neutron imaging (NI) is a-state-of-the-art non-destructive tool in the area of CH and plays an important role in the modern archeology. The NI technology can be widely utilized in the field of elemental analysis. At Egypt Second Research Reactor (ETRR-2), a collimated Neutron Radiography (NR) beam is employed for neutron imaging purposes. A digital CCD camera is utilized for recording the beam attenuation in the sample. This helps for the detection of hidden objects and characterization of material properties. Research activity can be extended to use computer software for quantitative neutron measurement. Development of image processing algorithms can be used to obtain high quality images. In this work, full description of ETRR-2 was introduced with up to date neutron imaging system as well. Tomographic investigation of a clay forged artifact represents CH object was studied by neutron imaging methods in order to obtain some hidden information and highlight some attractive quantitative measurements. Computer software was used for imaging processing and enhancement. Also the Astra Image 3.0 Pro software was employed for high precise measurements and imaging enhancement using advanced algorithms. This work increased the effective utilization of the ETRR-2 Neutron Radiography/Tomography (NR/T) technique in Culture Heritages activities. © 2013 Elsevier Ltd. All rights reserved.
Multimodality Data Integration in Epilepsy
Muzik, Otto; Chugani, Diane C.; Zou, Guangyu; Hua, Jing; Lu, Yi; Lu, Shiyong; Asano, Eishi; Chugani, Harry T.
2007-01-01
An important goal of software development in the medical field is the design of methods which are able to integrate information obtained from various imaging and nonimaging modalities into a cohesive framework in order to understand the results of qualitatively different measurements in a larger context. Moreover, it is essential to assess the various features of the data quantitatively so that relationships in anatomical and functional domains between complementing modalities can be expressed mathematically. This paper presents a clinically feasible software environment for the quantitative assessment of the relationship among biochemical functions as assessed by PET imaging and electrophysiological parameters derived from intracranial EEG. Based on the developed software tools, quantitative results obtained from individual modalities can be merged into a data structure allowing a consistent framework for advanced data mining techniques and 3D visualization. Moreover, an effort was made to derive quantitative variables (such as the spatial proximity index, SPI) characterizing the relationship between complementing modalities on a more generic level as a prerequisite for efficient data mining strategies. We describe the implementation of this software environment in twelve children (mean age 5.2 ± 4.3 years) with medically intractable partial epilepsy who underwent both high-resolution structural MR and functional PET imaging. Our experiments demonstrate that our approach will lead to a better understanding of the mechanisms of epileptogenesis and might ultimately have an impact on treatment. Moreover, our software environment holds promise to be useful in many other neurological disorders, where integration of multimodality data is crucial for a better understanding of the underlying disease mechanisms. PMID:17710251
Squitieri, Lee; Larson, Bradley P; Chang, Kate W C; Yang, Lynda J S; Chung, Kevin C
2013-12-01
To explore the quality of life (QOL) and patient expectations among adolescents with neonatal brachial plexus palsy (NBPP)and their parents using qualitative and quantitative approaches. A total of 18 adolescents (10-17 y) with residual NBPP impairment and their parents under went separate 1-hour tape-recorded semistructured interviews. We also collected quantitative physical examination measures and patient-rated outcome scores, specifically the Pediatric Outcomes Data Collection Instrument and the Child Health Questionnaire, to quantify the severity of each adolescent’s functional deficit and increase our understanding of QOL and patient expectations. Through qualitative analysis, we identified several patient- and system-dependent factors contributing to QOL, such as social impact and peer acceptance, emotional adjustment,aesthetic concerns and body image, functional limitations, physical and occupational therapy, finances, pain, and family dynamics. Despite residual impairment, most adolescents and their parents reported a good overall QOL according to quantitative outcome measures. Our study results showed that functional and aesthetic factors were responsible for most observed differences in QOL among NBPP adolescents. We also found that the Pediatric Outcomes Data Collection Instrument might be more sensitive than the Child Health Questionnaire in assessing patient expectations and QOL among this patient population. Understanding patient expectations and QOL in NBPP adolescents is essential for medical decision making and advancing care. Physical examination measurements alone may not be sufficient for measuring outcome, and knowledge regarding environmental factors and family dynamics is important for clinicians to consider when counseling families of children with NBPP and improving overall outcome. Prognostic IV.
ERIC Educational Resources Information Center
Rutledge, Michael L.; Mathis, Philip M.; Seipelt, Rebecca L.
2005-01-01
As students apply their knowledge of scientific concepts and of science as a method of inquiry, learning becomes relevant. This laboratory exercise is designed to foster students' understanding of the genetics of quantitative traits and of the nature of science as a method of inquiry by engaging them in a real-world business scenario. During the…
ERIC Educational Resources Information Center
Rodriguez-Barbero, A.; Lopez-Novoa, J. M.
2008-01-01
One of the problems that we have found when teaching human physiology in a Spanish medical school is that the degree of understanding by the students of the integration between organs and systems is rather poor. We attempted to remedy this problem by using a case discussion method together with the Quantitative Circulatory Physiology (QCP)…
ERIC Educational Resources Information Center
Mawanda, Haruna Juko
2012-01-01
The primary purpose of this nonexperimental, correlational, and descriptive quantitative study research was to gain an empirical understanding of the effects of transformational leadership and contingent reward as extrinsic motivation on employee satisfaction with leadership and leadership effectiveness in virtual team workplace environments.…
2017 Service Academy Gender Relations Focus Groups: Overview Report
2017-11-01
quantitative (survey) and qualitative (focus groups) assessment. Surveys provide an assessment of progress over time and a broad understanding of the...that were discussed across MSAs. Participants honed in on the comparatively low numbers of unwanted sexual contact (USC) for freshman and the relative...representative surveys are used to gain qualitative and quantitative feedback, respectively, from students and personnel at the Academies. This report
Dou, Shuping; Virostko, John; Greiner, Dale L.; Powers, Alvin C.; Liu, Guozheng
2016-01-01
Quantitative prediction of in vivo behavior using an in vitro assay would dramatically accelerate pharmaceutical development. However, studies quantitatively correlating in vivo properties with in vitro assay results are rare because of the difficulty in quantitatively understanding the in vivo behavior of an agent. We now demonstrate such a correlation as a case study based on our quantitative understanding of the in vivo chemistry. In an ongoing pretargeting project, we designed a trifunctional antibody (Ab) that concomitantly carried a biotin and a DNA analogue (hereafter termed MORF). The biotin and the MORF were fused into one structure prior to conjugation to the Ab for the concomitant attachment. Because it was known that avidin-bound Ab molecules leave the circulation rapidly, this design would theoretically allow complete clearance by avidin. The clearability of the trifunctional Ab was determined by calculating the blood MORF concentration ratio of avidin-treated Ab to non-avidin-treated Ab using mice injected with these compounds. In theory, any compromised clearability should be due to the presence of impurities. In vitro, we measured the biotinylated percentage of the Ab-reacting (MORF-biotin)⊃-NH2 modifier, by addition of streptavidin to the radiolabeled (MORF-biotin)⊃-NH2 samples and subsequent high-performance liquid chromatography (HPLC) analysis. On the basis of our previous quantitative understanding, we predicted that the clearability of the Ab would be equal to the biotinylation percentage measured via HPLC. We validated this prediction within a 3% difference. In addition to the high avidin-induced clearability of the trifunctional Ab (up to ~95%) achieved by the design, we were able to predict the required quality of the (MORF-biotin)⊃-NH2 modifier for any given in vivo clearability. This approach may greatly reduce the steps and time currently required in pharmaceutical development in the process of synthesis, chemical analysis, in vitro cell study, and in vivo validation. PMID:26103429
The Impact of Employment and Physical Activity on Academic Performance
ERIC Educational Resources Information Center
Andreopoulos, Giuliana Campanelli; Antoniou, Eliana; Panayides, Alexandros; Vassiliou, Evros
2008-01-01
Over the last twenty years, many contributions appeared on the relationship between working during school and academic performance using both quantitative and qualitative research methods. The obvious assumption is that a full time working student will show a lower academic performance relatively to a part time working student or a full time…
Learning Styles of Law Enforcement Officers: Does Police Work Affect How Officers Learn?
ERIC Educational Resources Information Center
Landry, John M.
2011-01-01
This quantitative study utilized the VARK learning style preference assessment instrument to examine how full-time sworn law enforcement officers learn and attempted to identify a predominant learning style preference among the participants. The primary question was: Which is the dominant learning style preference of full-time sworn law…
Factors that Predict Full-Time Community College Faculty Engagement in Online Instruction
ERIC Educational Resources Information Center
Akroyd, Duane; Patton, Bess; Bracken, Susan
2013-01-01
This study is a secondary quantitative analysis of the 2004 National Study of Postsecondary Faculty (NSOPF) data. It examines the ability of human capital, intrinsic rewards, extrinsic rewards, and gender/race demographics to predict full-time community college faculty teaching on-line courses. Findings indicate that those faculty with higher…
MO-E-12A-01: Quantitative Imaging: Techniques, Applications, and Challenges
DOE Office of Scientific and Technical Information (OSTI.GOV)
Jackson, E; Jeraj, R; McNitt-Gray, M
The first symposium in the Quantitative Imaging Track focused on the introduction of quantitative imaging (QI) by illustrating the potential of QI in diagnostic and therapeutic applications in research and patient care, highlighting key challenges in implementation of such QI applications, and reviewing QI efforts of selected national and international agencies and organizations, including the FDA, NCI, NIST, and RSNA. This second QI symposium will focus more specifically on the techniques, applications, and challenges of QI. The first talk of the session will focus on modalityagnostic challenges of QI, beginning with challenges of the development and implementation of QI applicationsmore » in single-center, single-vendor settings and progressing to the challenges encountered in the most general setting of multi-center, multi-vendor settings. The subsequent three talks will focus on specific QI challenges and opportunities in the modalityspecific settings of CT, PET/CT, and MR. Each talk will provide information on modality-specific QI techniques, applications, and challenges, including current efforts focused on solutions to such challenges. Learning Objectives: Understand key general challenges of QI application development and implementation, regardless of modality. Understand selected QI techniques and applications in CT, PET/CT, and MR. Understand challenges, and potential solutions for such challenges, for the applications presented for each modality.« less
Quantitative magnetic resonance imaging phantoms: A review and the need for a system phantom.
Keenan, Kathryn E; Ainslie, Maureen; Barker, Alex J; Boss, Michael A; Cecil, Kim M; Charles, Cecil; Chenevert, Thomas L; Clarke, Larry; Evelhoch, Jeffrey L; Finn, Paul; Gembris, Daniel; Gunter, Jeffrey L; Hill, Derek L G; Jack, Clifford R; Jackson, Edward F; Liu, Guoying; Russek, Stephen E; Sharma, Samir D; Steckner, Michael; Stupic, Karl F; Trzasko, Joshua D; Yuan, Chun; Zheng, Jie
2018-01-01
The MRI community is using quantitative mapping techniques to complement qualitative imaging. For quantitative imaging to reach its full potential, it is necessary to analyze measurements across systems and longitudinally. Clinical use of quantitative imaging can be facilitated through adoption and use of a standard system phantom, a calibration/standard reference object, to assess the performance of an MRI machine. The International Society of Magnetic Resonance in Medicine AdHoc Committee on Standards for Quantitative Magnetic Resonance was established in February 2007 to facilitate the expansion of MRI as a mainstream modality for multi-institutional measurements, including, among other things, multicenter trials. The goal of the Standards for Quantitative Magnetic Resonance committee was to provide a framework to ensure that quantitative measures derived from MR data are comparable over time, between subjects, between sites, and between vendors. This paper, written by members of the Standards for Quantitative Magnetic Resonance committee, reviews standardization attempts and then details the need, requirements, and implementation plan for a standard system phantom for quantitative MRI. In addition, application-specific phantoms and implementation of quantitative MRI are reviewed. Magn Reson Med 79:48-61, 2018. © 2017 International Society for Magnetic Resonance in Medicine. © 2017 International Society for Magnetic Resonance in Medicine.
Rao, Rohit T; Scherholz, Megerle L; Hartmanshenn, Clara; Bae, Seul-A; Androulakis, Ioannis P
2017-12-05
The use of models in biology has become particularly relevant as it enables investigators to develop a mechanistic framework for understanding the operating principles of living systems as well as in quantitatively predicting their response to both pathological perturbations and pharmacological interventions. This application has resulted in a synergistic convergence of systems biology and pharmacokinetic-pharmacodynamic modeling techniques that has led to the emergence of quantitative systems pharmacology (QSP). In this review, we discuss how the foundational principles of chemical process systems engineering inform the progressive development of more physiologically-based systems biology models.
A Quantitative Analysis of the Benefits of Prototyping Fixed-Wing Aircraft
2012-06-14
in then-year dollars. The RDT&E costs through FSD were provided in then-year dollars as a lump sum. Additionally, the cost of full capability ...development was available in then-year dollars as a lump sum. Full capability development was the RDT&E that continued after the completion of the FSD...contract, which ended in July 1984. In [31] [31], the authors stated that full capability development occurred through approximately 1990
Quantitative Resistance: More Than Just Perception of a Pathogen
2017-01-01
Molecular plant pathology has focused on studying large-effect qualitative resistance loci that predominantly function in detecting pathogens and/or transmitting signals resulting from pathogen detection. By contrast, less is known about quantitative resistance loci, particularly the molecular mechanisms controlling variation in quantitative resistance. Recent studies have provided insight into these mechanisms, showing that genetic variation at hundreds of causal genes may underpin quantitative resistance. Loci controlling quantitative resistance contain some of the same causal genes that mediate qualitative resistance, but the predominant mechanisms of quantitative resistance extend beyond pathogen recognition. Indeed, most causal genes for quantitative resistance encode specific defense-related outputs such as strengthening of the cell wall or defense compound biosynthesis. Extending previous work on qualitative resistance to focus on the mechanisms of quantitative resistance, such as the link between perception of microbe-associated molecular patterns and growth, has shown that the mechanisms underlying these defense outputs are also highly polygenic. Studies that include genetic variation in the pathogen have begun to highlight a potential need to rethink how the field considers broad-spectrum resistance and how it is affected by genetic variation within pathogen species and between pathogen species. These studies are broadening our understanding of quantitative resistance and highlighting the potentially vast scale of the genetic basis of quantitative resistance. PMID:28302676
Context Dependence of Students' Views about the Role of Equations in Understanding Biology
ERIC Educational Resources Information Center
Watkins, Jessica; Elby, Andrew
2013-01-01
Students' epistemological views about biology--their ideas about what "counts" as learning and understanding biology--play a role in how they approach their courses and respond to reforms. As introductory biology courses incorporate more physics and quantitative reasoning, student attitudes about the role of equations in biology become…
Does Delivery Format Make a Difference in Learning about Global and Cultural Understanding?
ERIC Educational Resources Information Center
Rawls, Janita; Hammons, Stacy A.
2016-01-01
This study assessed a learning outcome for nontraditional seniors who were in accelerated degree programs in both online and on-site formats. Using items from the National Survey of Student Engagement, researchers explored engagement with global understanding and cultural awareness. A quantitative, single-case analysis method was used to determine…
ERIC Educational Resources Information Center
Vela, Javier C.; Lenz, A. Stephen; Sparrow, Gregory Scott; Gonzalez, Stacey Lee
2017-01-01
Positive psychology is a useful framework to understand Mexican American adolescents' academic experiences. We used a quantitative, predictive design to explore how presence of meaning in life, search for meaning in life, subjective happiness, hope, and family importance influenced 131 Mexican American adolescents' college-going beliefs. We used…
ERIC Educational Resources Information Center
Hansen, John; Barnett, Michael; MaKinster, James; Keating, Thomas
2004-01-01
The increased availability of computational modeling software has created opportunities for students to engage in scientific inquiry through constructing computer-based models of scientific phenomena. However, despite the growing trend of integrating technology into science curricula, educators need to understand what aspects of these technologies…
ERIC Educational Resources Information Center
Berbary, Lisbeth A.
2012-01-01
While multiple and competing understandings of sororities exist in popular culture, academic research on sororities tends to homogenize the experience of sorority women, simplifying their existence to a quantitative understanding of specific behaviors such as those associated with binge drinking, eating disorders, and heterosexuality.…
Clock Work: How Tools for Time Mediate Problem Solving and Reveal Understanding
ERIC Educational Resources Information Center
Earnest, Darrell
2017-01-01
This article reports on elementary students' understanding of time in the context of common classroom manipulatives and notational systems. Students in Grades 2 (n = 72) and 4 (n = 72) participated in problem-solving interviews involving different clocks. Quantitative results revealed that students' performances were significantly different as a…
Understanding Cellular Respiration in Terms of Matter & Energy within Ecosystems
ERIC Educational Resources Information Center
White, Joshua S.; Maskiewicz, April C.
2014-01-01
Using a design-based research approach, we developed a data-rich problem (DRP) set to improve student understanding of cellular respiration at the ecosystem level. The problem tasks engage students in data analysis to develop biological explanations. Several of the tasks and their implementation are described. Quantitative results suggest that…
Resilience in Preschool Children--The Perspectives of Teachers, Parents and Children
ERIC Educational Resources Information Center
Miljevic-Ridicki, Renata; Plantak, Krešimir; Bouillet, Dejana
2017-01-01
The aim of this paper is to explore how parents, teachers and children in early years' education understand the concept of resilience. The paper analyses the understanding of the concept of resilience in a Croatian kindergarten using qualitative and quantitative research methods. The qualitative research consists of a thematic analysis of data…
Hammarlund-Udenaes, Margareta
2017-09-01
Microdialysis has contributed with very important knowledge to the understanding of target-specific concentrations and their relationship to pharmacodynamic effects from a systems pharmacology perspective, aiding in the global understanding of drug effects. This review focuses on the historical development of microdialysis as a method to quantify the pharmacologically very important unbound tissue concentrations and of recent findings relating to modeling microdialysis data to extrapolate from rodents to humans, understanding distribution of drugs in different tissues and disease conditions. Quantitative microdialysis developed very rapidly during the early 1990s. Method development was in focus in the early years including development of quantitative microdialysis, to be able to estimate true extracellular concentrations. Microdialysis has significantly contributed to the understanding of active transport at the blood-brain barrier and in other organs. Examples are presented where microdialysis together with modeling has increased the knowledge on tissue distribution between species, in overweight patients and in tumors, and in metabolite contribution to drug effects. More integrated metabolomic studies are still sparse within the microdialysis field, although a great potential for tissue and disease-specific measurements is evident.
1984-07-01
gather quantita- tive data on the flowering periods of various entomophilous plants at the study sites. Once the pollen relationships of the various bee...during 1983. For all hardwood species on study plots (i.e., test and control), bud burst, leaf out, full foliage, flowering , cambial activity, seed...value to megachilids e qualitative and quantitative determination of pertinent flowering phenologies o development of qualitative and quantitative
Determining the full costs of medical education in Thai Binh, Vietnam: a generalizable model.
Bicknell, W J; Beggs, A C; Tham, P V
2001-12-01
We summarize a model for determining the full cost of educating a medical student at Thai Binh Medical School in Vietnam. This is the first full-cost analysis of medical education in a low-income country in over 20 years. We emphasize policy implications and the importance of looking at the educational costs and service roles of the major health professions. In Vietnam fully subsidized medical education has given way to a system combining student-paid tuition and fees with decreased government subsidies. Full cost information facilitates resource management, setting tuition charges at a school and adjusting budget allocations between medical schools, teaching hospitals, and health centres. When linked to quality indicators, trends within and useful comparisons between schools are possible. Cost comparisons between different types of providers can assist policy-makers in judging the appropriateness of expenditures per graduate for nursing and allied health education versus physician education. If privatization of medical education is considered, cost analysis allows policy-makers to know the full costs of educating physicians including the subsidies required in clinical settings. Our approach is intuitively simple and provides useful, understandable new information to managers and policy-makers. The full cost per medical graduate in 1997 was 111 462 989 Vietnamese Dong (US$9527). The relative expenditure per Vietnamese physician educated was 2.8 times the expenditure in the United States when adjusted for GNP per capita. Preliminary findings suggest that, within Vietnam, the cost to educate a physician is 14 times the cost of educating a nurse. Given the direct costs of physician education, the lifetime earnings of physicians and the costs that physicians generate for the use of health services and supplies, it is remarkable that so little attention is paid to the costs of educating physicians. Studies of this type can provide the quantitative basis for vital human resource and health services policy considerations.
NASA Astrophysics Data System (ADS)
Arkebauer, T. J.; Walter-Shea, E. A.
2017-12-01
Vegetation indices, based on canopy spectral reflectance, are widely used to infer physical and biological characteristics of vegetation. Understanding the changes in remotely sensed signals as vegetation responds to its changing environment is essential for full assessment of canopy structure and function. Canopy-level reflectance has been measured at Nebraska AmeriFlux sites US-Ne1, US-Ne2 and US-Ne3 for most years since flux measurements were initiated in 2001. Tower-mounted spectral sensors provided 10-minute averaged reflectance (in PAR and NIR spectral regions) every half hour through the growing season for maize and soybean. Canopy reflectance varied over diurnal and seasonal time periods which led to variations in vegetation indices. One source of variation is due to the interaction of incident solar radiant energy with canopy structure (e.g., reflectance varies with changes in solar zenith angle and direct beam fraction, vegetative fraction, and leaf angle distribution). Another source of variation results from changes in canopy function (e.g., fluctuations in gross primary production and invocation of photoprotective mechanisms with plant stress). We present here a series of diurnal "patterns" of vegetation indices (including Normalized Difference Vegetation Index and Chlorophyll Index) for maize and soybean under mostly clear sky conditions. We demonstrate that diurnal patterns change as the LAI of the canopy changes through the course of the growing season in a somewhat predictable pattern from plant emergence (low vegetative cover) through peak green LAI (full vegetation cover). However, there are changes in the diurnal pattern that we have yet to fully understand; this variation in pattern may indicate variation in canopy function. Initially, we have explored the pattern changes qualitatively and are currently developing more quantitative approaches.
Pepin, K M; Spackman, E; Brown, J D; Pabilonia, K L; Garber, L P; Weaver, J T; Kennedy, D A; Patyk, K A; Huyvaert, K P; Miller, R S; Franklin, A B; Pedersen, K; Bogich, T L; Rohani, P; Shriner, S A; Webb, C T; Riley, S
2014-03-01
Wild birds are the primary source of genetic diversity for influenza A viruses that eventually emerge in poultry and humans. Much progress has been made in the descriptive ecology of avian influenza viruses (AIVs), but contributions are less evident from quantitative studies (e.g., those including disease dynamic models). Transmission between host species, individuals and flocks has not been measured with sufficient accuracy to allow robust quantitative evaluation of alternate control protocols. We focused on the United States of America (USA) as a case study for determining the state of our quantitative knowledge of potential AIV emergence processes from wild hosts to poultry. We identified priorities for quantitative research that would build on existing tools for responding to AIV in poultry and concluded that the following knowledge gaps can be addressed with current empirical data: (1) quantification of the spatio-temporal relationships between AIV prevalence in wild hosts and poultry populations, (2) understanding how the structure of different poultry sectors impacts within-flock transmission, (3) determining mechanisms and rates of between-farm spread, and (4) validating current policy-decision tools with data. The modeling studies we recommend will improve our mechanistic understanding of potential AIV transmission patterns in USA poultry, leading to improved measures of accuracy and reduced uncertainty when evaluating alternative control strategies. Copyright © 2013 The Authors. Published by Elsevier B.V. All rights reserved.
Full-Range Public Health Leadership, Part 2: Qualitative Analysis and Synthesis.
Carlton, Erik L; Holsinger, James W; Riddell, Martha C; Bush, Heather
2015-01-01
Public health leadership is an important topic in the era of U.S. health reform, population health innovation, and health system transformation. This study utilized the full-range leadership model in order to examine the public health leadership. We sought to understand local public health leadership from the perspective of local health department leaders and those who work with and for them. Public health leadership was explored through interviews and focus groups with directors (n = 4) and staff (n = 33) from local health departments. Qualitative analytic methods included reflexive journals, code-recode procedures, and member checking, with analysis facilitated by Atlas.ti v.6.0. Qualitative results supported and expanded upon previously reported quantitative findings. Leading by example and providing individual consideration to followers were found to be more important than other leader factors, such as intellectual stimulation, inspirational motivation, or idealized attributes of leaders. Having a clear and competent vision of public health, being able to work collaboratively with other community agencies, and addressing the current challenges to public health with creativity and innovation were also important findings. Idealized leadership behaviors and individual consideration should be the focus of student and professional development. Models that incorporate contextual considerations, such as the situational leadership model, could be utilized to ensure that optimal individual consideration is given to followers.
High Fidelity Simulation of Primary Atomization in Diesel Engine Sprays
NASA Astrophysics Data System (ADS)
Ivey, Christopher; Bravo, Luis; Kim, Dokyun
2014-11-01
A high-fidelity numerical simulation of jet breakup and spray formation from a complex diesel fuel injector at ambient conditions has been performed. A full understanding of the primary atomization process in fuel injection of diesel has not been achieved for several reasons including the difficulties accessing the optically dense region. Due to the recent advances in numerical methods and computing resources, high fidelity simulations of atomizing flows are becoming available to provide new insights of the process. In the present study, an unstructured un-split Volume-of-Fluid (VoF) method coupled to a stochastic Lagrangian spray model is employed to simulate the atomization process. A common rail fuel injector is simulated by using a nozzle geometry available through the Engine Combustion Network. The working conditions correspond to a single orifice (90 μm) JP-8 fueled injector operating at an injection pressure of 90 bar, ambient condition at 29 bar, 300 K filled with 100% nitrogen with Rel = 16,071, Wel = 75,334 setting the spray in the full atomization mode. The experimental dataset from Army Research Lab is used for validation in terms of spray global parameters and local droplet distributions. The quantitative comparison will be presented and discussed. Supported by Oak Ridge Associated Universities and the Army Research Laboratory.
Nieuwenhuijsen, Mark J; Khreis, Haneen; Verlinghieri, Ersilia; Mueller, Natalie; Rojas-Rueda, David
2017-06-01
Urban and transport planning have large impacts on public health, but these are generally not explicitly considered and/or quantified, partly because there are no comprehensive models, methods and tools readily available. Air pollution, noise, temperature, green space, motor vehicle crashes and physical activity are important pathways linking urban and transport planning and public health. For policy decision-making, it is important to understand and be able to quantify the full-chain from source through pathways to health effects and impacts to substantiate and effectively target actions. In this paper, we aim to provide an overview of recent studies on the health impacts related to urban and transport planning in cities, describe the need for novel participatory quantitative health impact assessments (HIA) and provide recommendations. To devise our searches and narrative, we were guided by a recent conceptual framework linking urban and transport planning, environmental exposures, behaviour and health. We searched PubMed, Web of Science, Science Direct, and references from relevant articles in English language from January 1, 1980, to November 1, 2016, using pre-defined search terms. The number of HIA studies is increasing rapidly, but there is lack of participatory integrated and full-chain HIA models, methods and tools. These should be based on the use of a systemic multidisciplinary/multisectorial approach and state-of-the-art methods to address questions such as what are the best, most feasible and needed urban and transport planning policy measures to improve public health in cities? Active citizen support and new forms of communication between experts and citizens and the involvement of all major stakeholders are crucial to find and successfully implement health promoting policy measures. We provided an overview of the current state-of-the art of HIA in cities and made recommendations for further work. The process on how to get there is as important and will provide answers to many crucial questions on e.g. how different disciplines can effectively work together, how to incorporate citizen and stakeholder opinion into quantitative HIA modelling for urban and transport planning, how different modelling and measurement methods can be effectively integrated, and whether a public health approach can bring about positive changes in urban and transport planning. Copyright © 2017. Published by Elsevier Ltd.
Quantitative proteomics in biological research.
Wilm, Matthias
2009-10-01
Proteomics has enabled the direct investigation of biological material, at first through the analysis of individual proteins, then of lysates from cell cultures, and finally of extracts from tissues and biopsies from entire organisms. Its latest manifestation - quantitative proteomics - allows deeper insight into biological systems. This article reviews the different methods used to extract quantitative information from mass spectra. It follows the technical developments aimed toward global proteomics, the attempt to characterize every expressed protein in a cell by at least one peptide. When applications of the technology are discussed, the focus is placed on yeast biology. In particular, differential quantitative proteomics, the comparison between an experiment and its control, is very discriminating for proteins involved in the process being studied. When trying to understand biological processes on a molecular level, differential quantitative proteomics tends to give a clearer picture than global transcription analyses. As a result, MS has become an even more indispensable tool for biochemically motivated biological research.
NASA Astrophysics Data System (ADS)
Wiskin, James; Klock, John; Iuanow, Elaine; Borup, Dave T.; Terry, Robin; Malik, Bilal H.; Lenox, Mark
2017-03-01
There has been a great deal of research into ultrasound tomography for breast imaging over the past 35 years. Few successful attempts have been made to reconstruct high-resolution images using transmission ultrasound. To this end, advances have been made in 2D and 3D algorithms that utilize either time of arrival or full wave data to reconstruct images with high spatial and contrast resolution suitable for clinical interpretation. The highest resolution and quantitative accuracy result from inverse scattering applied to full wave data in 3D. However, this has been prohibitively computationally expensive, meaning that full inverse scattering ultrasound tomography has not been considered clinically viable. Here we show the results of applying a nonlinear inverse scattering algorithm to 3D data in a clinically useful time frame. This method yields Quantitative Transmission (QT) ultrasound images with high spatial and contrast resolution. We reconstruct sound speeds for various 2D and 3D phantoms and verify these values with independent measurements. The data are fully 3D as is the reconstruction algorithm, with no 2D approximations. We show that 2D reconstruction algorithms can introduce artifacts into the QT breast image which are avoided by using a full 3D algorithm and data. We show high resolution gross and microscopic anatomic correlations comparing cadaveric breast QT images with MRI to establish imaging capability and accuracy. Finally, we show reconstructions of data from volunteers, as well as an objective visual grading analysis to confirm clinical imaging capability and accuracy.
Quantitative laser diagnostic and modeling study of C2 and CH chemistry in combustion.
Köhler, Markus; Brockhinke, Andreas; Braun-Unkhoff, Marina; Kohse-Höinghaus, Katharina
2010-04-15
Quantitative concentration measurements of CH and C(2) have been performed in laminar, premixed, flat flames of propene and cyclopentene with varying stoichiometry. A combination of cavity ring-down (CRD) spectroscopy and laser-induced fluorescence (LIF) was used to enable sensitive detection of these species with high spatial resolution. Previously, CH and C(2) chemistry had been studied, predominantly in methane flames, to understand potential correlations of their formation and consumption. For flames of larger hydrocarbon fuels, however, quantitative information on these small intermediates is scarce, especially under fuel-rich conditions. Also, the combustion chemistry of C(2) in particular has not been studied in detail, and although it has often been observed, its role in potential build-up reactions of higher hydrocarbon species is not well understood. The quantitative measurements performed here are the first to detect both species with good spatial resolution and high sensitivity in the same experiment in flames of C(3) and C(5) fuels. The experimental profiles were compared with results of combustion modeling to reveal details of the formation and consumption of these important combustion molecules, and the investigation was devoted to assist the further understanding of the role of C(2) and of its potential chemical interdependences with CH and other small radicals.
Wadephul, Franziska; Jones, Catriona; Jomeen, Julie
2016-06-08
Depression, anxiety and stress in the perinatal period can have serious, long-term consequences for women, their babies and their families. Over the last two decades, an increasing number of group interventions with a psychological approach have been developed to improve the psychological well-being of pregnant women. This systematic review examines interventions targeting women with elevated symptoms of, or at risk of developing, perinatal mental health problems, with the aim of understanding the successful and unsuccessful features of these interventions. We systematically searched online databases to retrieve qualitative and quantitative studies on psychological antenatal group interventions. A total number of 19 papers describing 15 studies were identified; these included interventions based on cognitive behavioural therapy, interpersonal therapy and mindfulness. Quantitative findings suggested beneficial effects in some studies, particularly for women with high baseline symptoms. However, overall there is insufficient quantitative evidence to make a general recommendation for antenatal group interventions. Qualitative findings suggest that women and their partners experience these interventions positively in terms of psychological wellbeing and providing reassurance of their 'normality'. This review suggests that there are some benefits to attending group interventions, but further research is required to fully understand their successful and unsuccessful features.
Atherton, K; Young, B; Salmon, P
2017-11-01
Clinical practice in haematological oncology often involves difficult diagnostic and treatment decisions. In this context, understanding patients' information needs and the functions that information serves for them is particularly important. We systematically reviewed qualitative and quantitative evidence on haematological oncology patients' information needs to inform how these needs can best be addressed in clinical practice. PsycINFO, Medline and CINAHL Plus electronic databases were searched for relevant empirical papers published from January 2003 to July 2016. Synthesis of the findings drew on meta-ethnography and meta-study. Most quantitative studies used a survey design and indicated that patients are largely content with the information they receive from physicians, however much or little they actually receive, although a minority of patients are not content with information. Qualitative studies suggest that a sense of being in a caring relationship with a physician allows patients to feel content with the information they have been given, whereas patients who lack such a relationship want more information. The qualitative evidence can help explain the lack of association between the amount of information received and contentment with it in the quantitative research. Trusting relationships are integral to helping patients feel that their information needs have been met. © 2017 John Wiley & Sons Ltd.
Quantitative Live-Cell Confocal Imaging of 3D Spheroids in a High-Throughput Format.
Leary, Elizabeth; Rhee, Claire; Wilks, Benjamin T; Morgan, Jeffrey R
2018-06-01
Accurately predicting the human response to new compounds is critical to a wide variety of industries. Standard screening pipelines (including both in vitro and in vivo models) often lack predictive power. Three-dimensional (3D) culture systems of human cells, a more physiologically relevant platform, could provide a high-throughput, automated means to test the efficacy and/or toxicity of novel substances. However, the challenge of obtaining high-magnification, confocal z stacks of 3D spheroids and understanding their respective quantitative limitations must be overcome first. To address this challenge, we developed a method to form spheroids of reproducible size at precise spatial locations across a 96-well plate. Spheroids of variable radii were labeled with four different fluorescent dyes and imaged with a high-throughput confocal microscope. 3D renderings of the spheroid had a complex bowl-like appearance. We systematically analyzed these confocal z stacks to determine the depth of imaging and the effect of spheroid size and dyes on quantitation. Furthermore, we have shown that this loss of fluorescence can be addressed through the use of ratio imaging. Overall, understanding both the limitations of confocal imaging and the tools to correct for these limits is critical for developing accurate quantitative assays using 3D spheroids.
Tutorial: Physics and modeling of Hall thrusters
NASA Astrophysics Data System (ADS)
Boeuf, Jean-Pierre
2017-01-01
Hall thrusters are very efficient and competitive electric propulsion devices for satellites and are currently in use in a number of telecommunications and government spacecraft. Their power spans from 100 W to 20 kW, with thrust between a few mN and 1 N and specific impulse values between 1000 and 3000 s. The basic idea of Hall thrusters consists in generating a large local electric field in a plasma by using a transverse magnetic field to reduce the electron conductivity. This electric field can extract positive ions from the plasma and accelerate them to high velocity without extracting grids, providing the thrust. These principles are simple in appearance but the physics of Hall thrusters is very intricate and non-linear because of the complex electron transport across the magnetic field and its coupling with the electric field and the neutral atom density. This paper describes the basic physics of Hall thrusters and gives a (non-exhaustive) summary of the research efforts that have been devoted to the modelling and understanding of these devices in the last 20 years. Although the predictive capabilities of the models are still not sufficient for a full computer aided design of Hall thrusters, significant progress has been made in the qualitative and quantitative understanding of these devices.
White, James L.; Newhouse, Rebecca J.; Zhang, Jin Z.; ...
2016-10-25
Alkali metal borohydrides can reversibly store hydrogen; however, the materials display poor cyclability, often times linked to occurrence of stable closo-polyborate intermediate species. In an effort to understand the role of such intermediates on the hydrogen storage properties of metal borohydrides, several alkali metal dodecahydro-closo-dodecaborate salts were isolated in anhydrous form and characterized by diffraction and spectroscopic techniques. Mixtures of Li 2B 12H 12, Na 2B 12H 12, and K 2B 12H 12 with the corresponding alkali metal hydrides were subjected to hydrogenation conditions known to favor partial or full reversibility in metal borohydrides. The stoichiometric mixtures of MH andmore » M 2B 12H 12 salts form the corresponding metal borohydrides MBH 4 (M=Li, Na, K) in almost quantitative yield at 100 MPa H 2 and 500 °C. In addition, stoichiometric mixtures of Li 2B 12H 12 and MgH 2 were found to form MgB 2 at 500 °C and above upon desorption in vacuum. The two destabilization strategies outlined above suggest that metal polyhydro-closo-polyborate species can be converted into the corresponding metal borohydrides or borides, albeit under rather harsh conditions of hydrogen pressure and temperature.« less
NASA Astrophysics Data System (ADS)
Monesi, C.; Meneghini, C.; Bardelli, F.; Benfatto, M.; Mobilio, S.; Manju, U.; Sarma, D. D.
2005-11-01
Hole-doped perovskites such as La1-xCaxMnO3 present special magnetic and magnetotransport properties, and it is commonly accepted that the local atomic structure around Mn ions plays a crucial role in determining these peculiar features. Therefore experimental techniques directly probing the local atomic structure, like x-ray absorption spectroscopy (XAS), have been widely exploited to deeply understand the physics of these compounds. Quantitative XAS analysis usually concerns the extended region [extended x-ray absorption fine structure (EXAFS)] of the absorption spectra. The near-edge region [x-ray absorption near-edge spectroscopy (XANES)] of XAS spectra can provide detailed complementary information on the electronic structure and local atomic topology around the absorber. However, the complexity of the XANES analysis usually prevents a quantitative understanding of the data. This work exploits the recently developed MXAN code to achieve a quantitative structural refinement of the Mn K -edge XANES of LaMnO3 and CaMnO3 compounds; they are the end compounds of the doped manganite series LaxCa1-xMnO3 . The results derived from the EXAFS and XANES analyses are in good agreement, demonstrating that a quantitative picture of the local structure can be obtained from XANES in these crystalline compounds. Moreover, the quantitative XANES analysis provides topological information not directly achievable from EXAFS data analysis. This work demonstrates that combining the analysis of extended and near-edge regions of Mn K -edge XAS spectra could provide a complete and accurate description of Mn local atomic environment in these compounds.
Heggen, Kristin Livelten; Pedersen, Hans Kristian; Andersen, Hilde Kjernlie; Martinsen, Anne Catrine T
2016-01-01
Background Iterative reconstruction can reduce image noise and thereby facilitate dose reduction. Purpose To evaluate qualitative and quantitative image quality for full dose and dose reduced head computed tomography (CT) protocols reconstructed using filtered back projection (FBP) and adaptive statistical iterative reconstruction (ASIR). Material and Methods Fourteen patients undergoing follow-up head CT were included. All patients underwent full dose (FD) exam and subsequent 15% dose reduced (DR) exam, reconstructed using FBP and 30% ASIR. Qualitative image quality was assessed using visual grading characteristics. Quantitative image quality was assessed using ROI measurements in cerebrospinal fluid (CSF), white matter, peripheral and central gray matter. Additionally, quantitative image quality was measured in Catphan and vendor’s water phantom. Results There was no significant difference in qualitative image quality between FD FBP and DR ASIR. Comparing same scan FBP versus ASIR, a noise reduction of 28.6% in CSF and between −3.7 and 3.5% in brain parenchyma was observed. Comparing FD FBP versus DR ASIR, a noise reduction of 25.7% in CSF, and −7.5 and 6.3% in brain parenchyma was observed. Image contrast increased in ASIR reconstructions. Contrast-to-noise ratio was improved in DR ASIR compared to FD FBP. In phantoms, noise reduction was in the range of 3 to 28% with image content. Conclusion There was no significant difference in qualitative image quality between full dose FBP and dose reduced ASIR. CNR improved in DR ASIR compared to FD FBP mostly due to increased contrast, not reduced noise. Therefore, we recommend using caution if reducing dose and applying ASIR to maintain image quality. PMID:27583169
Østerås, Bjørn Helge; Heggen, Kristin Livelten; Pedersen, Hans Kristian; Andersen, Hilde Kjernlie; Martinsen, Anne Catrine T
2016-08-01
Iterative reconstruction can reduce image noise and thereby facilitate dose reduction. To evaluate qualitative and quantitative image quality for full dose and dose reduced head computed tomography (CT) protocols reconstructed using filtered back projection (FBP) and adaptive statistical iterative reconstruction (ASIR). Fourteen patients undergoing follow-up head CT were included. All patients underwent full dose (FD) exam and subsequent 15% dose reduced (DR) exam, reconstructed using FBP and 30% ASIR. Qualitative image quality was assessed using visual grading characteristics. Quantitative image quality was assessed using ROI measurements in cerebrospinal fluid (CSF), white matter, peripheral and central gray matter. Additionally, quantitative image quality was measured in Catphan and vendor's water phantom. There was no significant difference in qualitative image quality between FD FBP and DR ASIR. Comparing same scan FBP versus ASIR, a noise reduction of 28.6% in CSF and between -3.7 and 3.5% in brain parenchyma was observed. Comparing FD FBP versus DR ASIR, a noise reduction of 25.7% in CSF, and -7.5 and 6.3% in brain parenchyma was observed. Image contrast increased in ASIR reconstructions. Contrast-to-noise ratio was improved in DR ASIR compared to FD FBP. In phantoms, noise reduction was in the range of 3 to 28% with image content. There was no significant difference in qualitative image quality between full dose FBP and dose reduced ASIR. CNR improved in DR ASIR compared to FD FBP mostly due to increased contrast, not reduced noise. Therefore, we recommend using caution if reducing dose and applying ASIR to maintain image quality.
Quantitative cell biology: the essential role of theory.
Howard, Jonathon
2014-11-05
Quantitative biology is a hot area, as evidenced by the recent establishment of institutes, graduate programs, and conferences with that name. But what is quantitative biology? What should it be? And how can it contribute to solving the big questions in biology? The past decade has seen very rapid development of quantitative experimental techniques, especially at the single-molecule and single-cell levels. In this essay, I argue that quantitative biology is much more than just the quantitation of these experimental results. Instead, it should be the application of the scientific method by which measurement is directed toward testing theories. In this view, quantitative biology is the recognition that theory and models play critical roles in biology, as they do in physics and engineering. By tying together experiment and theory, quantitative biology promises a deeper understanding of underlying mechanisms, when the theory works, or to new discoveries, when it does not. © 2014 Howard. This article is distributed by The American Society for Cell Biology under license from the author(s). Two months after publication it is available to the public under an Attribution–Noncommercial–Share Alike 3.0 Unported Creative Commons License (http://creativecommons.org/licenses/by-nc-sa/3.0).
Quantitative and statistical analysis Power grid topology of the Western Interconnection Energy storage for grid applications Research Interests Understanding the implications of high penetrations of renewable
ERIC Educational Resources Information Center
Salinas, Dino G.; Reyes, Juan G.
2015-01-01
Qualitative questions are proposed to assess the understanding of solubility and some of its applications. To improve those results, a simple quantitative problem on the precipitation of proteins is proposed.
State of reporting of primary biomedical research: a scoping review protocol
Mbuagbaw, Lawrence; Samaan, Zainab; Jin, Yanling; Nwosu, Ikunna; Levine, Mitchell A H; Adachi, Jonathan D; Thabane, Lehana
2017-01-01
Introduction Incomplete or inconsistent reporting remains a major concern in the biomedical literature. Incomplete or inconsistent reporting may yield the published findings unreliable, irreproducible or sometimes misleading. In this study based on evidence from systematic reviews and surveys that have evaluated the reporting issues in primary biomedical studies, we aim to conduct a scoping review with focuses on (1) the state-of-the-art extent of adherence to the emerging reporting guidelines in primary biomedical research, (2) the inconsistency between protocols or registrations and full reports and (3) the disagreement between abstracts and full-text articles. Methods and analyses We will use a comprehensive search strategy to retrieve all available and eligible systematic reviews and surveys in the literature. We will search the following electronic databases: Web of Science, Excerpta Medica Database (EMBASE), MEDLINE and Cumulative Index to Nursing and Allied Health Literature (CINAHL). Our outcomes are levels of adherence to reporting guidelines, levels of consistency between protocols or registrations and full reports and the agreement between abstracts and full reports, all of which will be expressed as percentages, quality scores or categorised rating (such as high, medium and low). No pooled analyses will be performed quantitatively given the heterogeneity of the included systematic reviews and surveys. Likewise, factors associated with improved completeness and consistency of reporting will be summarised qualitatively. The quality of the included systematic reviews will be evaluated using AMSTAR (a measurement tool to assess systematic reviews). Ethics and dissemination All findings will be published in peer-reviewed journals and relevant conferences. These results may advance our understanding of the extent of incomplete and inconsistent reporting, factors related to improved completeness and consistency of reporting and potential recommendations for various stakeholders in the biomedical community. PMID:28360252
Tateishi-Karimata, Hisae; Isono, Noburu; Sugimoto, Naoki
2014-01-01
The thermal stability and topology of non-canonical structures of G-quadruplexes and hairpins in template DNA were investigated, and the effect of non-canonical structures on transcription fidelity was evaluated quantitatively. We designed ten template DNAs: A linear sequence that does not have significant higher-order structure, three sequences that form hairpin structures, and six sequences that form G-quadruplex structures with different stabilities. Templates with non-canonical structures induced the production of an arrested, a slipped, and a full-length transcript, whereas the linear sequence produced only a full-length transcript. The efficiency of production for run-off transcripts (full-length and slipped transcripts) from templates that formed the non-canonical structures was lower than that from the linear. G-quadruplex structures were more effective inhibitors of full-length product formation than were hairpin structure even when the stability of the G-quadruplex in an aqueous solution was the same as that of the hairpin. We considered that intra-polymerase conditions may differentially affect the stability of non-canonical structures. The values of transcription efficiencies of run-off or arrest transcripts were correlated with stabilities of non-canonical structures in the intra-polymerase condition mimicked by 20 wt% polyethylene glycol (PEG). Transcriptional arrest was induced when the stability of the G-quadruplex structure (-ΔG°37) in the presence of 20 wt% PEG was more than 8.2 kcal mol(-1). Thus, values of stability in the presence of 20 wt% PEG are an important indicator of transcription perturbation. Our results further our understanding of the impact of template structure on the transcription process and may guide logical design of transcription-regulating drugs.
Cavallo, Cheryl L; Richter, Randy R
2004-01-01
Development of attitudes of physical therapists (PTs) toward physical therapist assistants (PTAs) begins during their professional education, and attitudes are influenced further by clinical experiences. The purpose of this study was to understand attitudes of student PTs toward PTAs. We surveyed 66 clinical intern students enrolled in an entry-level master of physical therapy program. PT students received the same survey before and after their full-time clinical internship. Eleven Likert scale items were used to assess students' attitudes toward PTAs in the areas of competence, financial remuneration, and job security. One item was designed to determine whether PT students' level of contact with PTAs influenced attitudes. A random sample of 13 (20.9%) students who returned surveys were asked to participate in a telephone interview designed to enrich the quantitative data. After item analysis, five of the scale items were eliminated from the analyses due to poor internal consistency. Cronbach's alpha of the remaining six scale items was 0.75. Survey results reveal that PT students maintain an overall positive attitude toward PTAs before and after full-time clinical internship. Qualitative interview data support this finding. Students' attitudes in specific areas of PTA competence were negative and positive, however. The negative attitude may have been based on the students' beliefs that PTAs are not competent to perform physical therapy in situations that are changing or unpredictable. Positive attitudes may have been reflective of the students' beliefs that PTAs are competent to implement established plans of care. Student ranking of four professional issues showed a significant difference before and after full-time clinical internships.
Tateishi-Karimata, Hisae; Isono, Noburu; Sugimoto, Naoki
2014-01-01
The thermal stability and topology of non-canonical structures of G-quadruplexes and hairpins in template DNA were investigated, and the effect of non-canonical structures on transcription fidelity was evaluated quantitatively. We designed ten template DNAs: A linear sequence that does not have significant higher-order structure, three sequences that form hairpin structures, and six sequences that form G-quadruplex structures with different stabilities. Templates with non-canonical structures induced the production of an arrested, a slipped, and a full-length transcript, whereas the linear sequence produced only a full-length transcript. The efficiency of production for run-off transcripts (full-length and slipped transcripts) from templates that formed the non-canonical structures was lower than that from the linear. G-quadruplex structures were more effective inhibitors of full-length product formation than were hairpin structure even when the stability of the G-quadruplex in an aqueous solution was the same as that of the hairpin. We considered that intra-polymerase conditions may differentially affect the stability of non-canonical structures. The values of transcription efficiencies of run-off or arrest transcripts were correlated with stabilities of non-canonical structures in the intra-polymerase condition mimicked by 20 wt% polyethylene glycol (PEG). Transcriptional arrest was induced when the stability of the G-quadruplex structure (−ΔGo 37) in the presence of 20 wt% PEG was more than 8.2 kcal mol−1. Thus, values of stability in the presence of 20 wt% PEG are an important indicator of transcription perturbation. Our results further our understanding of the impact of template structure on the transcription process and may guide logical design of transcription-regulating drugs. PMID:24594642
NASA Astrophysics Data System (ADS)
Alexander, M. Joan; Stephan, Claudia
2015-04-01
In climate models, gravity waves remain too poorly resolved to be directly modelled. Instead, simplified parameterizations are used to include gravity wave effects on model winds. A few climate models link some of the parameterized waves to convective sources, providing a mechanism for feedback between changes in convection and gravity wave-driven changes in circulation in the tropics and above high-latitude storms. These convective wave parameterizations are based on limited case studies with cloud-resolving models, but they are poorly constrained by observational validation, and tuning parameters have large uncertainties. Our new work distills results from complex, full-physics cloud-resolving model studies to essential variables for gravity wave generation. We use the Weather Research Forecast (WRF) model to study relationships between precipitation, latent heating/cooling and other cloud properties to the spectrum of gravity wave momentum flux above midlatitude storm systems. Results show the gravity wave spectrum is surprisingly insensitive to the representation of microphysics in WRF. This is good news for use of these models for gravity wave parameterization development since microphysical properties are a key uncertainty. We further use the full-physics cloud-resolving model as a tool to directly link observed precipitation variability to gravity wave generation. We show that waves in an idealized model forced with radar-observed precipitation can quantitatively reproduce instantaneous satellite-observed features of the gravity wave field above storms, which is a powerful validation of our understanding of waves generated by convection. The idealized model directly links observations of surface precipitation to observed waves in the stratosphere, and the simplicity of the model permits deep/large-area domains for studies of wave-mean flow interactions. This unique validated model tool permits quantitative studies of gravity wave driving of regional circulation and provides a new method for future development of realistic convective gravity wave parameterizations.
Quantitative documentation of a premenstrual flare of facial acne in adult women.
Lucky, Anne W
2004-04-01
To quantitatively document the presence and extent of a late luteal (premenstrual) acne flare in adult women. Case series. Subjects were recruited from a general community dermatology practice and by advertising. Adult women 18 to 44 years old with normal periods who were receiving no treatment for their acne. Acne lesion counts were surveyed over the follicular and luteal phases of 2 full menstrual cycles. Most (63%) of these women showed a 25% premenstrual increase in the number of inflammatory acne lesions. This is the first quantitative documentation of the presence and degree of premenstrual acne flares in adult women.
A review of presented mathematical models in Parkinson's disease: black- and gray-box models.
Sarbaz, Yashar; Pourakbari, Hakimeh
2016-06-01
Parkinson's disease (PD), one of the most common movement disorders, is caused by damage to the central nervous system. Despite all of the studies on PD, the formation mechanism of its symptoms remained unknown. It is still not obvious why damage only to the substantia nigra pars compacta, a small part of the brain, causes a wide range of symptoms. Moreover, the causes of brain damages remain to be fully elucidated. Exact understanding of the brain function seems to be impossible. On the other hand, some engineering tools are trying to understand the behavior and performance of complex systems. Modeling is one of the most important tools in this regard. Developing quantitative models for this disease has begun in recent decades. They are very effective not only in better understanding of the disease, offering new therapies, and its prediction and control, but also in its early diagnosis. Modeling studies include two main groups: black-box models and gray-box models. Generally, in the black-box modeling, regardless of the system information, the symptom is only considered as the output. Such models, besides the quantitative analysis studies, increase our knowledge of the disorders behavior and the disease symptoms. The gray-box models consider the involved structures in the symptoms appearance as well as the final disease symptoms. These models can effectively save time and be cost-effective for the researchers and help them select appropriate treatment mechanisms among all possible options. In this review paper, first, efforts are made to investigate some studies on PD quantitative analysis. Then, PD quantitative models will be reviewed. Finally, the results of using such models are presented to some extent.
Mid-Frequency Reverberation Measurements with Full Companion Environmental Support
2014-12-30
acoustic modeling is based on measured stratification and observed wave amplitudes on the New Jersey shelf during the SWARM experiment.3 Ray tracing is...wave model then gives quantitative results for the clutter. 2. Swarm NLIW model and ray tracing Nonlinear internal waves are very common on the...receiver in order to give quantitative clutter to reverberation. To picture the mechanism, a set of rays was launched from a source at range zero and
Early Understandings of Simple Food Chains: A Learning Progression for the Preschool Years
ERIC Educational Resources Information Center
Allen, Michael
2017-01-01
Aspects of preschoolers' ecological understandings were explored in a cross-age, quantitative study that utilised a sample of seventy-five 3- to 5-year-old children. Specifically, their concepts of feeding relationships were determined by presenting physical models of three-step food chains during structured interviews. A majority of children,…
ERIC Educational Resources Information Center
Schuchardt, Anita M.; Schunn, Christian D.
2016-01-01
Amid calls for integrating science, technology, engineering, and mathematics (iSTEM) in K-12 education, there is a pressing need to uncover productive methods of integration. Prior research has shown that increasing contextual linkages between science and mathematics is associated with student problem solving and conceptual understanding. However,…
ERIC Educational Resources Information Center
Muslihah, Oleh Eneng
2015-01-01
The research examines the correlation between the understanding of school-based management, emotional intelligences and headmaster performance. Data was collected, using quantitative methods. The statistical analysis used was the Pearson Correlation, and multivariate regression analysis. The results of this research suggest firstly that there is…
ERIC Educational Resources Information Center
Garcia, Gina A.; Huerta, Adrian H.; Ramirez, Jenesis J.; Patrón, Oscar E.
2017-01-01
As the number of Latino males entering college increases, there is a need to understand their unique leadership experiences. This study used a convergent parallel mixed methods design to understand what contexts contribute to Latino male undergraduate students' leadership development, capacity, and experiences. Quantitative data were gathered by…
ERIC Educational Resources Information Center
Matthews, Kelly E.; Belward, Shaun; Coady, Carmel; Rylands, Leanne; Simbag, Vilma
2016-01-01
Higher education policies are increasingly focused on graduate learning outcomes, which infer an emphasis on, and deep understanding of, curriculum development across degree programs. As disciplinary influences are known to shape teaching and learning activities, research situated in disciplinary contexts is useful to further an understanding of…
The Impact of Project-Based Learning on Fourth-Grade Students' Understanding in Reading
ERIC Educational Resources Information Center
Williams, Dana L.
2017-01-01
The purpose of this quantitative, non-experimental, descriptive study was to determine if participation in project-based learning developed the understanding students need to transfer their knowledge and skills to achieve higher composite and reading scores, as well as demonstrate the ability to read increasingly complex texts on the ACT Aspire as…
ERIC Educational Resources Information Center
Sasson, Ayelet
2017-01-01
Motivations for study abroad have been studied mostly from a quantitative point of view. This study attempted to understand those motivations through qualitative methodology, by getting "into the heads" of international students using a multiple case study approach. Participants were 15 Israeli Hebrew-speaking graduates. Data sources…
ERIC Educational Resources Information Center
Morrow, Jennifer Ann; Kelly, Stephanie; Skolits, Gary
2013-01-01
Understanding and conducting research is a complex, integral skill that needs to be mastered by both undergraduate and graduate students. Yet many students are reluctant and often somewhat apprehensive about undertaking research and understanding the underlying statistical methods used to evaluate research (Dauphinee, Schau, & Stevens, 1997).…
Educators' Understanding of the Mediation Role in the Classroom
ERIC Educational Resources Information Center
Ngidi, D. P.
2012-01-01
This study investigated educators' understanding of the mediation role in the classroom. A quantitative research approach was used in a survey of a sample of 261 participants. To this end, a questionnaire was used for collecting data. The Chi-square test was used to analyse data and to test the hypotheses of the study. The findings indicated that…
ERIC Educational Resources Information Center
Hernandez, Gabriel E.; Criswell, Brett A.; Kirk, Nancy J.; Sauder, Deborah G.; Rushton, Gregory T.
2014-01-01
In the past three decades, researchers have noted the limitations of a problem-solving approach that overemphasizes algorithms and quantitation and neglects student misconceptions and an otherwise qualitative, conceptual understanding of chemical phenomena. Since then, studies and lessons designed to improve student understanding of chemistry has…
ERIC Educational Resources Information Center
Bodzin, Alec M.; Fu, Qiong
2014-01-01
Climate change science is a challenging topic for student learning. This quantitative study examined the effectiveness of a geospatial curriculum approach to promote climate change science understandings in an urban school district with eighth-grade students and investigated whether teacher- and student-level factors accounted for students'…
3D Printing and Digital Rock Physics for the Geosciences
NASA Astrophysics Data System (ADS)
Martinez, M. J.; Yoon, H.; Dewers, T. A.
2014-12-01
Imaging techniques for the analysis of porous structures have revolutionized our ability to quantitatively characterize geomaterials. For example, digital representations of rock from CT images and physics modeling based on these pore structures provide the opportunity to further advance our quantitative understanding of fluid flow, geomechanics, and geochemistry, and the emergence of coupled behaviors. Additive manufacturing, commonly known as 3D printing, has revolutionized production of custom parts, to the point where parts might be cheaper to print than to make by traditional means in a plant and ship. Some key benefits of additive manufacturing include short lead times, complex shapes, parts on demand, zero required inventory and less material waste. Even subtractive processing, such as milling and etching, may be economized by additive manufacturing. For the geosciences, recent advances in 3D printing technology may be co-opted to print reproducible porous structures derived from CT-imaging of actual rocks for experimental testing. The use of 3D printed microstructure allows us to surmount typical problems associated with sample-to-sample heterogeneity that plague rock physics testing and to test material response independent from pore-structure variability. Together, imaging, digital rocks and 3D printing potentially enables a new workflow for understanding coupled geophysical processes in a real, but well-defined setting circumventing typical issues associated with reproducibility, enabling full characterization and thus connection of physical phenomena to structure. In this talk we will discuss the possibilities that the marriage of these technologies can bring to geosciences, including examples from our current research initiatives in developing constitutive laws for transport and geomechanics via digital rock physics. Sandia National Laboratories is a multi-program laboratory managed and operated by Sandia Corporation, a wholly owned subsidiary of Lockheed Martin Corporation, for the U.S. Department of Energy's National Nuclear Security Administration under contract DE-AC04-94AL85000.
NASA Astrophysics Data System (ADS)
Volpi, Giorgio; Riva, Federico; Frattini, Paolo; Battista Crosta, Giovanni; Magri, Fabien
2016-04-01
Thermal springs are widespread in the European Alps, where more than 80 geothermal sites are known and exploited. The quantitative assessment of those thermal flow systems is a challenging issue and requires accurate conceptual model and a thorough understanding of thermo-hydraulic properties of the aquifers. Accordingly in the last years, several qualitative studies were carried out to understand the heat and fluid transport processes driving deep fluids from the reservoir to the springs. Our work focused on thermal circulation and fluid outflows of the area around Bormio (Central Italian Alps), where nine geothermal springs discharge from dolomite bodies located close to a regional alpine thrust, called the Zebrù Line. At this site, water is heated in deep circulation systems and vigorously upwells at temperature of about 40°C. The aim of this paper is to explore the mechanisms of heat and fluid transport in the Bormio area by carrying out refined steady and transient three-dimensional finite element simulations of thermally-driven flow and to quantitatively assess the source area of the thermal waters. The full regional model (ca. 700 km2) is discretized with a highly refined triangular finite element planar grid obtained with Midas GTS NX software. The structural 3D features of the regional Zebrù thrust are built by interpolating series of geological cross sections using Fracman. A script was developed to convert and implement the thrust grid into FEFLOW mesh that comprises ca. 4 million elements. The numerical results support the observed discharge rates and temperature field within the simulated domain. Flow and temperature patterns suggest that thermal groundwater flows through a deep system crossing both sedimentary and metamorphic lithotypes, and a fracture network associated to the thrust system. Besides providing a numerical framework to simulate complex fractured systems, this example gives insights into the influence of deep alpine structures on groundwater circulation that underlies the development of many hydrothermal systems.
Cole, Scott N; Morrison, Catriona M; Barak, Ohr; Pauly-Takacs, Katalin; Conway, Martin A
2016-06-01
To examine the impact of memory accessibility on episodic future thinking. Single-case study of neurological patient HCM and an age-matched comparison group of neurologically Healthy Controls. We administered a full battery of tests assessing general intelligence, memory, and executive functioning. To assess autobiographical memory, the Autobiographical Memory Interview (Kopelman, Wilson, & Baddeley, 1990. The Autobiographical Memory Interview. Bury St. Edmunds, UK: Thames Valley Test Company) was administered. The Past Episodic and Future Episodic sections of Dalla Barba's Confabulation Battery (Dalla Barba, 1993, Cogn. Neuropsychol., 1, 1) and a specifically tailored Mental Time Travel Questionnaire were administered to assess future thinking in HCM and age-matched controls. HCM presented with a deficit in forming new memories (anterograde amnesia) and recalling events from before the onset of neurological impairment (retrograde amnesia). HCM's autobiographical memory impairments are characterized by a paucity of memories from Recent Life. In comparison with controls, two features of his future thoughts are apparent: Reduced episodic future thinking and outdated content of his episodic future thoughts. This article suggests neuropsychologists should look beyond popular conceptualizations of the past-future relation in amnesia via focussing on reduced future thinking. Investigating both the quantity and quality of future thoughts produced by amnesic patients may lead to developments in understanding the complex nature of future thinking disorders resulting from memory impairments. We highlight the clinical importance of examining the content of future thoughts in amnesic patients, rather than only its quantitative reduction. We propose an explanation of how quantitative and qualitative aspects of future thinking could be affected by amnesia. This could provide a useful approach to understand clinical cases of impaired prospection. Systematic group investigations are required to fully examine our hypothesis. Although the current study utilized typical future thinking measures, these may be limited and we highlight the need to develop clinically relevant measures of prospection. © 2015 The British Psychological Society.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Wu, Bingjing; Zhao, Jianlin, E-mail: jlzhao@nwpu.edu.cn; Wang, Jun
2013-11-21
We present a method for visually and quantitatively investigating the heat dissipation process of plate-fin heat sinks by using digital holographic interferometry. A series of phase change maps reflecting the temperature distribution and variation trend of the air field surrounding heat sink during the heat dissipation process are numerically reconstructed based on double-exposure holographic interferometry. According to the phase unwrapping algorithm and the derived relationship between temperature and phase change of the detection beam, the full-field temperature distributions are quantitatively obtained with a reasonably high measurement accuracy. And then the impact of heat sink's channel width on the heat dissipationmore » performance in the case of natural convection is analyzed. In addition, a comparison between simulation and experiment results is given to verify the reliability of this method. The experiment results certify the feasibility and validity of the presented method in full-field, dynamical, and quantitative measurement of the air field temperature distribution, which provides a basis for analyzing the heat dissipation performance of plate-fin heat sinks.« less
Genomic Quantitative Genetics to Study Evolution in the Wild.
Gienapp, Phillip; Fior, Simone; Guillaume, Frédéric; Lasky, Jesse R; Sork, Victoria L; Csilléry, Katalin
2017-12-01
Quantitative genetic theory provides a means of estimating the evolutionary potential of natural populations. However, this approach was previously only feasible in systems where the genetic relatedness between individuals could be inferred from pedigrees or experimental crosses. The genomic revolution opened up the possibility of obtaining the realized proportion of genome shared among individuals in natural populations of virtually any species, which could promise (more) accurate estimates of quantitative genetic parameters in virtually any species. Such a 'genomic' quantitative genetics approach relies on fewer assumptions, offers a greater methodological flexibility, and is thus expected to greatly enhance our understanding of evolution in natural populations, for example, in the context of adaptation to environmental change, eco-evolutionary dynamics, and biodiversity conservation. Copyright © 2017 Elsevier Ltd. All rights reserved.
Kumar, Jitendra; Hoffman, Forrest M.; Hargrove, William W.; ...
2016-08-23
Eddy covariance data from regional flux networks are direct in situ measurement of carbon, water, and energy fluxes and are of vital importance for understanding the spatio-temporal dynamics of the the global carbon cycle. FLUXNET links regional networks of eddy covariance sites across the globe to quantify the spatial and temporal variability of fluxes at regional to global scales and to detect emergent ecosystem properties. This study presents an assessment of the representativeness of FLUXNET based on the recently released FLUXNET2015 data set. We present a detailed high resolution analysis of the evolving representativeness of FLUXNET through time. Results providemore » quantitative insights into the extent that various biomes are sampled by the network of networks, the role of the spatial distribution of the sites on the network scale representativeness at any given time, and how that representativeness has changed through time due to changing operational status and data availability at sites in the network. To realize the full potential of FLUXNET observations for understanding emergent ecosystem properties at regional and global scales, we present an approach for upscaling eddy covariance measurements. Informed by the representativeness of observations at the flux sites in the network, the upscaled data reflects the spatio-temporal dynamics of the carbon cycle captured by the in situ measurements. In conclusion, this study presents a method for optimal use of the rich point measurements from FLUXNET to derive an understanding of upscaled carbon fluxes, which can be routinely updated as new data become available, and direct network expansion by identifying regions poorly sampled by the current network.« less
Art-Science-Technology collaboration through immersive, interactive 3D visualization
NASA Astrophysics Data System (ADS)
Kellogg, L. H.
2014-12-01
At the W. M. Keck Center for Active Visualization in Earth Sciences (KeckCAVES), a group of geoscientists and computer scientists collaborate to develop and use of interactive, immersive, 3D visualization technology to view, manipulate, and interpret data for scientific research. The visual impact of immersion in a CAVE environment can be extremely compelling, and from the outset KeckCAVES scientists have collaborated with artists to bring this technology to creative works, including theater and dance performance, installations, and gamification. The first full-fledged collaboration designed and produced a performance called "Collapse: Suddenly falling down", choreographed by Della Davidson, which investigated the human and cultural response to natural and man-made disasters. Scientific data (lidar scans of disaster sites, such as landslides and mine collapses) were fully integrated into the performance by the Sideshow Physical Theatre. This presentation will discuss both the technological and creative characteristics of, and lessons learned from the collaboration. Many parallels between the artistic and scientific process emerged. We observed that both artists and scientists set out to investigate a topic, solve a problem, or answer a question. Refining that question or problem is an essential part of both the creative and scientific workflow. Both artists and scientists seek understanding (in this case understanding of natural disasters). Differences also emerged; the group noted that the scientists sought clarity (including but not limited to quantitative measurements) as a means to understanding, while the artists embraced ambiguity, also as a means to understanding. Subsequent art-science-technology collaborations have responded to evolving technology for visualization and include gamification as a means to explore data, and use of augmented reality for informal learning in museum settings.
Miniaturization of Fresnel lenses for solar concentration: a quantitative investigation.
Duerr, Fabian; Meuret, Youri; Thienpont, Hugo
2010-04-20
Sizing down the dimensions of solar concentrators for photovoltaic applications offers a number of promising advantages. It provides thinner modules and smaller solar cells, which reduces thermal issues. In this work a plane Fresnel lens design is introduced that is first analyzed with geometrical optics. Because of miniaturization, pure ray tracing may no longer be valid to determine the concentration performance. Therefore, a quantitative wave optical analysis of the miniaturization's influence on the obtained concentration performance is presented. This better quantitative understanding of the impact of diffraction in microstructured Fresnel lenses might help to optimize the design of several applications in nonimaging optics.
A combined qualitative and quantitative procedure for the chemical analysis of urinary calculi
Hodgkinson, A.
1971-01-01
A better understanding of the physico-chemical principles underlying the formation of calculus has led to a need for more precise information on the chemical composition of stones. A combined qualitative and quantitative procedure for the chemical analysis of urinary calculi which is suitable for routine use is presented. The procedure involves five simple qualitative tests followed by the quantitative determination of calcium, magnesium, inorganic phosphate, and oxalate. These data are used to calculate the composition of the stone in terms of calcium oxalate, apatite, and magnesium ammonium phosphate. Analytical results and derived values for five representative types of calculi are presented. PMID:5551382
Design of 3-D adipospheres for quantitative metabolic study
Akama, Takeshi; Leung, Brendan M.; Labuz, Joseph M.; Takayama, Shuichi; Chun, Tae-Hwa
2017-01-01
Quantitative assessment of adipose mitochondrial activity is critical for better understanding of adipose tissue function in obesity and diabetes. While the two-dimensional (2-D) tissue culture method has been sufficient to discover key molecules that regulate adipocyte differentiation and function, the method is insufficient to determine the role of extracellular matrix (ECM) molecules and their modifiers, such as matrix metalloproteinases (MMPs), in regulating adipocyte function in three-dimensional (3-D) in vivo-like microenvironments. By using a 3-D hanging drop tissue culture system, we are able to produce scalable 3-D adipospheres that are suitable for quantitative mitochondrial study in 3-D microenvironment. PMID:28244051
General description and understanding of the nonlinear dynamics of mode-locked fiber lasers.
Wei, Huai; Li, Bin; Shi, Wei; Zhu, Xiushan; Norwood, Robert A; Peyghambarian, Nasser; Jian, Shuisheng
2017-05-02
As a type of nonlinear system with complexity, mode-locked fiber lasers are known for their complex behaviour. It is a challenging task to understand the fundamental physics behind such complex behaviour, and a unified description for the nonlinear behaviour and the systematic and quantitative analysis of the underlying mechanisms of these lasers have not been developed. Here, we present a complexity science-based theoretical framework for understanding the behaviour of mode-locked fiber lasers by going beyond reductionism. This hierarchically structured framework provides a model with variable dimensionality, resulting in a simple view that can be used to systematically describe complex states. Moreover, research into the attractors' basins reveals the origin of stochasticity, hysteresis and multistability in these systems and presents a new method for quantitative analysis of these nonlinear phenomena. These findings pave the way for dynamics analysis and system designs of mode-locked fiber lasers. We expect that this paradigm will also enable potential applications in diverse research fields related to complex nonlinear phenomena.
Murphy, Kevin G.; Jones, Nick S.
2018-01-01
Obesity is a major global public health problem. Understanding how energy homeostasis is regulated, and can become dysregulated, is crucial for developing new treatments for obesity. Detailed recording of individual behaviour and new imaging modalities offer the prospect of medically relevant models of energy homeostasis that are both understandable and individually predictive. The profusion of data from these sources has led to an interest in applying machine learning techniques to gain insight from these large, relatively unstructured datasets. We review both physiological models and machine learning results across a diverse range of applications in energy homeostasis, and highlight how modelling and machine learning can work together to improve predictive ability. We collect quantitative details in a comprehensive mathematical supplement. We also discuss the prospects of forecasting homeostatic behaviour and stress the importance of characterizing stochasticity within and between individuals in order to provide practical, tailored forecasts and guidance to combat the spread of obesity. PMID:29367240
Holzweber, Markus; Lippitz, Andreas; Krueger, Katharina; Jankowski, Joachim; Unger, Wolfgang E S
2015-03-24
The surfaces of polymeric dialyzer membranes consisting of polysulfone and polyvinylpyrrolidone were investigated regarding the lateral distribution and quantitative surface composition using time-of-flight secondary-ion-mass-spectrometry and x-ray photoelectron spectroscopy. Knowledge of the distribution and composition on the outer surface region is of utmost importance for understanding the biocompatibility of such dialyzer membranes. Both flat membranes and hollow fiber membranes were studied.
Electric and Magnetic Interactions
NASA Astrophysics Data System (ADS)
Chabay, Ruth W.; Sherwood, Bruce A.
1994-08-01
The curriculum has been restructured so that students will have the necessary fundamental understanding of charges and fields before going on to more complex issues. Qualitative reasoning and quantitative analysis are discussed equally in order to provide a meaningful conceptual framework within which the quantitative work makes more sense. Atomic-level analysis is stressed and electrostatics and circuits are unified. Desktop experiments can be conducted at home or in the classroom and are tightly integrated with the theoretical treatment.
Chemotherapy is used to treat most cancer patients, yet our understanding of factors that dictate response and resistance to such drugs remains limited. We report the generation of a quantitative chemical-genetic interaction map in human mammary epithelial cells charting the impact of the knockdown of 625 genes related to cancer and DNA repair on sensitivity to 29 drugs, covering all classes of chemotherapy.
Nearly every cancer patient is treated with chemotherapy yet our understanding of factors that dictate response and resistance to such agents remains limited. We report the generation of a quantitative chemical-genetic interaction map in human mammary epithelial cells that charts the impact of knockdown of 625 cancer and DNA repair related genes on sensitivity to 29 drugs, covering all classes of cancer chemotherapeutics.
Quantitative Resistance: More Than Just Perception of a Pathogen.
Corwin, Jason A; Kliebenstein, Daniel J
2017-04-01
Molecular plant pathology has focused on studying large-effect qualitative resistance loci that predominantly function in detecting pathogens and/or transmitting signals resulting from pathogen detection. By contrast, less is known about quantitative resistance loci, particularly the molecular mechanisms controlling variation in quantitative resistance. Recent studies have provided insight into these mechanisms, showing that genetic variation at hundreds of causal genes may underpin quantitative resistance. Loci controlling quantitative resistance contain some of the same causal genes that mediate qualitative resistance, but the predominant mechanisms of quantitative resistance extend beyond pathogen recognition. Indeed, most causal genes for quantitative resistance encode specific defense-related outputs such as strengthening of the cell wall or defense compound biosynthesis. Extending previous work on qualitative resistance to focus on the mechanisms of quantitative resistance, such as the link between perception of microbe-associated molecular patterns and growth, has shown that the mechanisms underlying these defense outputs are also highly polygenic. Studies that include genetic variation in the pathogen have begun to highlight a potential need to rethink how the field considers broad-spectrum resistance and how it is affected by genetic variation within pathogen species and between pathogen species. These studies are broadening our understanding of quantitative resistance and highlighting the potentially vast scale of the genetic basis of quantitative resistance. © 2017 American Society of Plant Biologists. All rights reserved.
NASA Astrophysics Data System (ADS)
Rachmawati, E.; Nurohman, S.; Widowati, A.
2018-01-01
This study aims to know: 1) the feasibility LKPD review of aspects of the didactic requirements, construction requirements, technical requirements and compliance with the Learning Cycle. 2) Increase understanding of learners with Learning Model Learning Cycle in SMP N 1 Wates in the form LKPD. 3) The response of learners and educators SMP N 1 Wates to quality LKPD Transportation Systems Beings. This study is an R & D with the 4D model (Define, Design, Develop and Disseminate). Data were analyzed using qualitative analysis and quantitative analysis. Qualitative analysis in the form of advice description and assessment scores from all validates that was converted to a scale of 4. While the analysis of quantitative data by calculating the percentage of materializing learning and achievement using the standard gain an increased understanding and calculation of the KKM completeness evaluation value as an indicator of the achievement of students understanding. the results of this study yield LKPD IPA model learning Cycle theme Transportation Systems Beings obtain 108.5 total scores of a maximum score of 128 including the excellent category (A). LKPD IPA developed able to demonstrate an improved understanding of learners and the response of learners was very good to this quality LKPD IPA.
Kaddi, Chanchala D.; Bennett, Rachel V.; Paine, Martin R. L.; Banks, Mitchel D.; Weber, Arthur L.; Fernández, Facundo M.; Wang, May D.
2016-01-01
Full characterization of complex reaction mixtures is necessary to understand mechanisms, optimize yields, and elucidate secondary reaction pathways. Molecular-level information for species in such mixtures can be readily obtained by coupling mass spectrometry imaging (MSI) with thin layer chromatography (TLC) separations. User-guided investigation of imaging data for mixture components with known m/z values is generally straightforward; however, spot detection for unknowns is highly tedious, and limits the applicability of MSI in conjunction with TLC. To accelerate imaging data mining, we developed DetectTLC, an approach that automatically identifies m/z values exhibiting TLC spot-like regions in MS molecular images. Furthermore, DetectTLC can also spatially match m/z values for spots acquired during alternating high and low collision-energy scans, pairing product ions with precursors to enhance structural identification. As an example, DetectTLC is applied to the identification and structural confirmation of unknown, yet significant, products of abiotic pyrazinone and aminopyrazine nucleoside analog synthesis. PMID:26508443
Flores-Huerta, S; Hernández-Montes, H; Argote, R M; Villalpando, S
1992-01-01
Although information about the pregnancy outcome of alcoholic mothers is relatively abundant, no information is available about the effects of ethanol consumption on the infant's postnatal growth. This investigation aims to describe the physical growth of 32 infants born to mothers accustomed to drinking pulque, a mild alcoholic beverage, on a daily basis during pregnancy and lactation and to quantitate the ethanol disposed through the milk, as well as to identify cases of newborns with fetal alcohol syndrome. No full-blown cases of the syndrome were found: birth weight was similar to their non-drinking counterpart, but the relative risk of newborns to drinking mothers to have a low birth weight was 3.39. Ethanol found in milk accounted for 40 mg/day available to the infant. The postnatal growth of infants of ethanol drinkers was similar to that of controls. Further studies on their mental development are required in order to understand the extent of the effects of such a habit.
Real-time individualized training vectors for experiential learning.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Willis, Matt; Tucker, Eilish Marie; Raybourn, Elaine Marie
2011-01-01
Military training utilizing serious games or virtual worlds potentially generate data that can be mined to better understand how trainees learn in experiential exercises. Few data mining approaches for deployed military training games exist. Opportunities exist to collect and analyze these data, as well as to construct a full-history learner model. Outcomes discussed in the present document include results from a quasi-experimental research study on military game-based experiential learning, the deployment of an online game for training evidence collection, and results from a proof-of-concept pilot study on the development of individualized training vectors. This Lab Directed Research & Development (LDRD)more » project leveraged products within projects, such as Titan (Network Grand Challenge), Real-Time Feedback and Evaluation System, (America's Army Adaptive Thinking and Leadership, DARWARS Ambush! NK), and Dynamic Bayesian Networks to investigate whether machine learning capabilities could perform real-time, in-game similarity vectors of learner performance, toward adaptation of content delivery, and quantitative measurement of experiential learning.« less
Understanding the LIGO GW150914 event
NASA Astrophysics Data System (ADS)
Naselsky, Pavel; Jackson, Andrew D.; Liu, Hao
2016-08-01
We present a simplified method for the extraction of meaningful signals from Hanford and Livingston 32 second data for the GW150914 event made publicly available by the LIGO collaboration, and demonstrate its ability to reproduce the LIGO collaboration's own results quantitatively given the assumption that all narrow peaks in the power spectrum are a consequence of physically uninteresting signals and can be removed. After the clipping of these peaks and return to the time domain, the GW150914 event is readily distinguished from broadband background noise. This simple technique allows us to identify the GW150914 event without any assumption regarding its physical origin and with minimal assumptions regarding its shape. We also confirm that the LIGO GW150914 event is uniquely correlated in the Hanford and Livingston detectors for the full 4096 second data at the level of 6-7 σ with a temporal displacement of τ = 6.9 ± 0.4 ms. We have also identified a few events that are morphologically close to GW150914 but less strongly cross correlated with it.
Magnon spectrum of the helimagnetic insulator Cu 2OSeO 3
Portnichenko, P. Y.; Romhányi, J.; Onykiienko, Y. A.; ...
2016-02-25
We report that complex low-temperature-ordered states in chiral magnets are typically governed by a competition between multiple magnetic interactions. The chiral-lattice multiferroic Cu 2OSeO 3 became the first insulating helimagnetic material in which a long-range order of topologically stable spin vortices known as skyrmions was established. Here we employ state-of-the-art inelastic neutron scattering to comprehend the full three-dimensional spin-excitation spectrum of Cu 2OSeO 3 over a broad range of energies. Distinct types of high- and low-energy dispersive magnon modes separated by an extensive energy gap are observed in excellent agreement with the previously suggested microscopic theory based on a modelmore » of entangled Cu 4 tetrahedra. The comparison of our neutron spectroscopy data with model spin-dynamical calculations based on these theoretical proposals enables an accurate quantitative verification of the fundamental magnetic interactions in Cu 2OSeO 3 that are essential for understanding its abundant low-temperature magnetically ordered phases.« less
Magnon spectrum of the helimagnetic insulator Cu2OSeO3
Portnichenko, P. Y.; Romhányi, J.; Onykiienko, Y. A.; Henschel, A.; Schmidt, M.; Cameron, A. S.; Surmach, M. A.; Lim, J. A.; Park, J. T.; Schneidewind, A.; Abernathy, D. L.; Rosner, H.; van den Brink, Jeroen; Inosov, D. S.
2016-01-01
Complex low-temperature-ordered states in chiral magnets are typically governed by a competition between multiple magnetic interactions. The chiral-lattice multiferroic Cu2OSeO3 became the first insulating helimagnetic material in which a long-range order of topologically stable spin vortices known as skyrmions was established. Here we employ state-of-the-art inelastic neutron scattering to comprehend the full three-dimensional spin-excitation spectrum of Cu2OSeO3 over a broad range of energies. Distinct types of high- and low-energy dispersive magnon modes separated by an extensive energy gap are observed in excellent agreement with the previously suggested microscopic theory based on a model of entangled Cu4 tetrahedra. The comparison of our neutron spectroscopy data with model spin-dynamical calculations based on these theoretical proposals enables an accurate quantitative verification of the fundamental magnetic interactions in Cu2OSeO3 that are essential for understanding its abundant low-temperature magnetically ordered phases. PMID:26911567
Draguta, Sergiu; Christians, Jeffrey A.; Morozov, Yurii V.; ...
2018-01-01
Hybrid perovskites represent a potential paradigm shift for the creation of low-cost solar cells. Current power conversion efficiencies (PCEs) exceed 22%. However, despite this, record PCEs are still far from their theoretical Shockley–Queisser limit of 31%. To increase these PCE values, there is a pressing need to understand, quantify and microscopically model charge recombination processes in full working devices. Here, we present a complete microscopic account of charge recombination processes in high efficiency (18–19% PCE) hybrid perovskite (mixed cation and methylammonium lead iodide) solar cells. We employ diffraction-limited optical measurements along with relevant kinetic modeling to establish, for the firstmore » time, local photoluminescence quantum yields, trap densities, trapping efficiencies, charge extraction efficiencies, quasi-Fermi-level splitting, and effective PCE estimates. Correlations between these spatially resolved parameters, in turn, allow us to conclude that intrinsic electron traps in the perovskite active layers limit the performance of these state-of-the-art hybrid perovskite solar cells.« less
Magnon spectrum of the helimagnetic insulator Cu2OSeO3.
Portnichenko, P Y; Romhányi, J; Onykiienko, Y A; Henschel, A; Schmidt, M; Cameron, A S; Surmach, M A; Lim, J A; Park, J T; Schneidewind, A; Abernathy, D L; Rosner, H; van den Brink, Jeroen; Inosov, D S
2016-02-25
Complex low-temperature-ordered states in chiral magnets are typically governed by a competition between multiple magnetic interactions. The chiral-lattice multiferroic Cu2OSeO3 became the first insulating helimagnetic material in which a long-range order of topologically stable spin vortices known as skyrmions was established. Here we employ state-of-the-art inelastic neutron scattering to comprehend the full three-dimensional spin-excitation spectrum of Cu2OSeO3 over a broad range of energies. Distinct types of high- and low-energy dispersive magnon modes separated by an extensive energy gap are observed in excellent agreement with the previously suggested microscopic theory based on a model of entangled Cu4 tetrahedra. The comparison of our neutron spectroscopy data with model spin-dynamical calculations based on these theoretical proposals enables an accurate quantitative verification of the fundamental magnetic interactions in Cu2OSeO3 that are essential for understanding its abundant low-temperature magnetically ordered phases.
NASA Astrophysics Data System (ADS)
Yi, Xiaoyan; Zhang, Huan; Liu, Guangxing
2014-05-01
Pelagic copepods play an important role in the marine food web. However, a full understanding of the ecological status of this zooplankton group depends on the careful study of their natural diets. In previous PCR-based copepod diet studies, we found many apostome ciliates that live symbiotically under the exoskeleton of the copepods, and their sequences were often over-represented in the 18S rRNA gene (18S rDNA) libraries. As a first step to address this issue, we designed three apostome ciliate 18S rDNA blocking primers, and tested their blocking efficiency against apostome ciliate 18s rDNA under various PCR conditions. Using a semi-quantitative PCR method, we optimized the conditions to efficiently amplify the 18S rDNA of the prey while simultaneously excluding the symbiotic apostome ciliates. This technique will facilitate PCR-based diet studies of copepods and other zooplankton in their natural environments.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Draguta, Sergiu; Christians, Jeffrey A.; Morozov, Yurii V.
Hybrid perovskites represent a potential paradigm shift for the creation of low-cost solar cells. Current power conversion efficiencies (PCEs) exceed 22%. However, despite this, record PCEs are still far from their theoretical Shockley–Queisser limit of 31%. To increase these PCE values, there is a pressing need to understand, quantify and microscopically model charge recombination processes in full working devices. Here, we present a complete microscopic account of charge recombination processes in high efficiency (18–19% PCE) hybrid perovskite (mixed cation and methylammonium lead iodide) solar cells. We employ diffraction-limited optical measurements along with relevant kinetic modeling to establish, for the firstmore » time, local photoluminescence quantum yields, trap densities, trapping efficiencies, charge extraction efficiencies, quasi-Fermi-level splitting, and effective PCE estimates. Correlations between these spatially resolved parameters, in turn, allow us to conclude that intrinsic electron traps in the perovskite active layers limit the performance of these state-of-the-art hybrid perovskite solar cells.« less
Smeal, Steven W; Schmitt, Margaret A; Pereira, Ronnie Rodrigues; Prasad, Ashok; Fisk, John D
2017-01-01
To expand the quantitative, systems level understanding and foster the expansion of the biotechnological applications of the filamentous bacteriophage M13, we have unified the accumulated quantitative information on M13 biology into a genetically-structured, experimentally-based computational simulation of the entire phage life cycle. The deterministic chemical kinetic simulation explicitly includes the molecular details of DNA replication, mRNA transcription, protein translation and particle assembly, as well as the competing protein-protein and protein-nucleic acid interactions that control the timing and extent of phage production. The simulation reproduces the holistic behavior of M13, closely matching experimentally reported values of the intracellular levels of phage species and the timing of events in the M13 life cycle. The computational model provides a quantitative description of phage biology, highlights gaps in the present understanding of M13, and offers a framework for exploring alternative mechanisms of regulation in the context of the complete M13 life cycle. Copyright © 2016 Elsevier Inc. All rights reserved.
ERIC Educational Resources Information Center
Nichols, Sarah K.
2012-01-01
Student retention is socially, politically, and financially important to educational institutions. This quantitative study explored the gap in research regarding the relationship between employment of part-time in lieu of full-time faculty and student retention. The campus climate exchange model (CCEM), served as the conceptual framework in this…
2012-01-01
Background Drug resistance in the malaria parasite Plasmodium falciparum severely compromises the treatment and control of malaria. A knowledge of the critical mutations conferring resistance to particular drugs is important in understanding modes of drug action and mechanisms of resistances. They are required to design better therapies and limit drug resistance. A mutation in the gene (pfcrt) encoding a membrane transporter has been identified as a principal determinant of chloroquine resistance in P. falciparum, but we lack a full account of higher level chloroquine resistance. Furthermore, the determinants of resistance in the other major human malaria parasite, P. vivax, are not known. To address these questions, we investigated the genetic basis of chloroquine resistance in an isogenic lineage of rodent malaria parasite P. chabaudi in which high level resistance to chloroquine has been progressively selected under laboratory conditions. Results Loci containing the critical genes were mapped by Linkage Group Selection, using a genetic cross between the high-level chloroquine-resistant mutant and a genetically distinct sensitive strain. A novel high-resolution quantitative whole-genome re-sequencing approach was used to reveal three regions of selection on chr11, chr03 and chr02 that appear progressively at increasing drug doses on three chromosomes. Whole-genome sequencing of the chloroquine-resistant parent identified just four point mutations in different genes on these chromosomes. Three mutations are located at the foci of the selection valleys and are therefore predicted to confer different levels of chloroquine resistance. The critical mutation conferring the first level of chloroquine resistance is found in aat1, a putative aminoacid transporter. Conclusions Quantitative trait loci conferring selectable phenotypes, such as drug resistance, can be mapped directly using progressive genome-wide linkage group selection. Quantitative genome-wide short-read genome resequencing can be used to reveal these signatures of drug selection at high resolution. The identities of three genes (and mutations within them) conferring different levels of chloroquine resistance generate insights regarding the genetic architecture and mechanisms of resistance to chloroquine and other drugs. Importantly, their orthologues may now be evaluated for critical or accessory roles in chloroquine resistance in human malarias P. vivax and P. falciparum. PMID:22435897
On the role of electron-driven processes in planetary atmospheres and comets
NASA Astrophysics Data System (ADS)
Campbell, L.; Brunger, M. J.
2009-11-01
After the presence of ionized layers in the Earth's atmosphere was inferred, it took 50 years to quantitatively understand them. The electron density could not be accounted for until Sir David Bates first suggested (along with Sir Harrie Massey) that the main electron-loss process was dissociative recombination with molecular ions, and he and colleagues then developed a theory to predict those rates of dissociative recombination. However, electron impact processes, particularly excitation, have been considered insignificant in most situations, in both planetary and cometary atmospheres. Here we describe cases where recent calculations have shown that electron impact excitation of molecules is important, suggesting that, just as in the time of Sir David Bates, electron-driven processes remain fundamental to our quantitative understanding of atmospheric and cometary phenomena.
Nonclassical Kinetics of Clonal yet Heterogeneous Enzymes.
Park, Seong Jun; Song, Sanggeun; Jeong, In-Chun; Koh, Hye Ran; Kim, Ji-Hyun; Sung, Jaeyoung
2017-07-06
Enzyme-to-enzyme variation in the catalytic rate is ubiquitous among single enzymes created from the same genetic information, which persists over the lifetimes of living cells. Despite advances in single-enzyme technologies, the lack of an enzyme reaction model accounting for the heterogeneous activity of single enzymes has hindered a quantitative understanding of the nonclassical stochastic outcome of single enzyme systems. Here we present a new statistical kinetics and exactly solvable models for clonal yet heterogeneous enzymes with possibly nonergodic state dynamics and state-dependent reactivity, which enable a quantitative understanding of modern single-enzyme experimental results for the mean and fluctuation in the number of product molecules created by single enzymes. We also propose a new experimental measure of the heterogeneity and nonergodicity for a system of enzymes.
Embryoids, organoids and gastruloids: new approaches to understanding embryogenesis
2017-01-01
ABSTRACT Cells have an intrinsic ability to self-assemble and self-organize into complex and functional tissues and organs. By taking advantage of this ability, embryoids, organoids and gastruloids have recently been generated in vitro, providing a unique opportunity to explore complex embryological events in a detailed and highly quantitative manner. Here, we examine how such approaches are being used to answer fundamental questions in embryology, such as how cells self-organize and assemble, how the embryo breaks symmetry, and what controls timing and size in development. We also highlight how further improvements to these exciting technologies, based on the development of quantitative platforms to precisely follow and measure subcellular and molecular events, are paving the way for a more complete understanding of the complex events that help build the human embryo. PMID:28292844
Plant hormone signaling during development: insights from computational models.
Oliva, Marina; Farcot, Etienne; Vernoux, Teva
2013-02-01
Recent years have seen an impressive increase in our knowledge of the topology of plant hormone signaling networks. The complexity of these topologies has motivated the development of models for several hormones to aid understanding of how signaling networks process hormonal inputs. Such work has generated essential insights into the mechanisms of hormone perception and of regulation of cellular responses such as transcription in response to hormones. In addition, modeling approaches have contributed significantly to exploring how spatio-temporal regulation of hormone signaling contributes to plant growth and patterning. New tools have also been developed to obtain quantitative information on hormone distribution during development and to test model predictions, opening the way for quantitative understanding of the developmental roles of hormones. Copyright © 2012 Elsevier Ltd. All rights reserved.
Artificial neural networks applied to quantitative elemental analysis of organic material using PIXE
NASA Astrophysics Data System (ADS)
Correa, R.; Chesta, M. A.; Morales, J. R.; Dinator, M. I.; Requena, I.; Vila, I.
2006-08-01
An artificial neural network (ANN) has been trained with real-sample PIXE (particle X-ray induced emission) spectra of organic substances. Following the training stage ANN was applied to a subset of similar samples thus obtaining the elemental concentrations in muscle, liver and gills of Cyprinus carpio. Concentrations obtained with the ANN method are in full agreement with results from one standard analytical procedure, showing the high potentiality of ANN in PIXE quantitative analyses.
Common-path digital holographic microscopy based on a beam displacer unit
NASA Astrophysics Data System (ADS)
Di, Jianglei; Zhang, Jiwei; Song, Yu; Wang, Kaiqiang; Wei, Kun; Zhao, Jianlin
2018-02-01
Digital holographic microscopy (DHM) has become a novel tool with advantages of full field, non-destructive, high-resolution and 3D imaging, which captures the quantitative amplitude and phase information of microscopic specimens. It's a well-established method for digital recording and numerical reconstructing the full complex field of wavefront of the samples with a diffraction-limited lateral resolution down to 0.3 μm depending on the numerical aperture of microscope objective. Meanwhile, its axial resolution through axial direction is less than 10 nm due to the interferometric nature in phase imaging. Compared with the typical optical configurations such as Mach-Zehnder interferometer and Michelson interferometer, the common-path DHM has the advantages of simple and compact configuration, high stability, and so on. Here, a simple, compact, and low-cost common-path DHM based on a beam displacer unit is proposed for quantitative phase imaging of biological cells. The beam displacer unit is completely compatible with commercial microscope and can be easily set up in the output port of the microscope as a compact independent device. This technique can be used to achieve the quantitative phase measurement of biological cells with an excellent temporal stability of 0.51 nm, which makes it having a good prospect in the fields of biological and medical science. Living mouse osteoblastic cells are quantitatively measured with the system to demonstrate its capability and applicability.
An experimental design for quantification of cardiovascular responses to music stimuli in humans.
Chang, S-H; Luo, C-H; Yeh, T-L
2004-01-01
There have been several researches on the relationship between music and human physiological or psychological responses. However, there are cardiovascular index factors that have not been explored quantitatively due to the qualitative nature of acoustic stimuli. This study proposes and demonstrates an experimental design for quantification of cardiovascular responses to music stimuli in humans. The system comprises two components: a unit for generating and monitoring quantitative acoustic stimuli and a portable autonomic nervous system (ANS) analysis unit for quantitative recording and analysis of the cardiovascular responses. The experimental results indicate that the proposed system can exactly achieve the goal of full control and measurement for the music stimuli, and also effectively support many quantitative indices of cardiovascular response in humans. In addition, the analysis results are discussed and predicted in the future clinical research.
ERIC Educational Resources Information Center
Selcuk, Gamze Sezgin
2011-01-01
The aim of this study is to investigate pre-service teachers' understanding of and difficulties with some core concepts in the special theory of relativity. The pre-service teachers (n = 185) from the Departments of Physics Education and Elementary Science Education at Dokuz Eylul University (in Turkey) participated. Both quantitative and…
ERIC Educational Resources Information Center
Al Khawaldeh, Suhaib
2015-01-01
The present study attempts to investigate the problems of understanding English ironic expressions M.A. of Applied Linguistics students at Mu'tah University in Jordan. This quantitative and qualitative study includes 15 of M.A. students of Applied Linguistics at Mu'tah University. The participants were selected randomly. Two research instruments…
ERIC Educational Resources Information Center
Harvey, Stephen; Cushion, Christopher J.; Wegis, Heidi M.; Massa-Gonzalez, Ada N.
2010-01-01
Background: Previous research examining the effectiveness of the Teaching Games for Understanding (TGfU) approach has been equivocal. This has been hampered by a dependence on a comparative (i.e., "which method is best?") theoretical framework. An alternative "practice-referenced" framework has the potential to examine the effectiveness of TGfU…
ERIC Educational Resources Information Center
Lunsford, M. Leigh; Rowell, Ginger Holmes; Goodson-Espy, Tracy
2006-01-01
We applied a classroom research model to investigate student understanding of sampling distributions of sample means and the Central Limit Theorem in post-calculus introductory probability and statistics courses. Using a quantitative assessment tool developed by previous researchers and a qualitative assessment tool developed by the authors, we…
The Pressure Available for Ground Cooling in Front of the Cowling of Air-cooled Airplane Engines
NASA Technical Reports Server (NTRS)
Stickle, George W; Joyner, Upshur T
1938-01-01
A study was made of the factors affecting the pressure available for ground cooling in front of a cowling. Most of the results presented were obtained with a set-up that was about one-third full scale. A number of isolated tests on four full-scale airplanes were made to determine the general applicability of the model results. The full-scale tests indicated that the model results may be applied qualitatively to full-scale design and quantitatively as a first approximation of the front pressure available for ground cooling.
Understanding Cytokine and Growth Factor Receptor Activation Mechanisms
Atanasova, Mariya; Whitty, Adrian
2012-01-01
Our understanding of the detailed mechanism of action of cytokine and growth factor receptors – and particularly our quantitative understanding of the link between structure, mechanism and function – lags significantly behind our knowledge of comparable functional protein classes such as enzymes, G protein-coupled receptors, and ion channels. In particular, it remains controversial whether such receptors are activated by a mechanism of ligand-induced oligomerization, versus a mechanism in which the ligand binds to a pre-associated receptor dimer or oligomer that becomes activated through subsequent conformational rearrangement. A major limitation to progress has been the relative paucity of methods for performing quantitative mechanistic experiments on unmodified receptors expressed at endogenous levels on live cells. In this article we review the current state of knowledge on the activation mechanisms of cytokine and growth factor receptors, critically evaluate the evidence for and against the different proposed mechanisms, and highlight other key questions that remain unanswered. New approaches and techniques have led to rapid recent progress in this area, and the field is poised for major advances in the coming years, which promises to revolutionize our understanding of this large and biologically and medically important class of receptors. PMID:23046381
Understanding online health information: Evaluation, tools, and strategies.
Beaunoyer, Elisabeth; Arsenault, Marianne; Lomanowska, Anna M; Guitton, Matthieu J
2017-02-01
Considering the status of the Internet as a prominent source of health information, assessing online health material has become a central issue in patient education. We describe the strategies available to evaluate the characteristics of online health information, including readability, emotional content, understandability, usability. Popular tools used in assessment of readability, emotional content and comprehensibility of online health information were reviewed. Tools designed to evaluate both printed and online material were considered. Readability tools are widely used in online health material evaluation and are highly covariant. Assessment of emotional content of online health-related communications via sentiment analysis tools is becoming more popular. Understandability and usability tools have been developed specifically for health-related material, but each tool has important limitations and has been tested on a limited number of health issues. Despite the availability of numerous assessment tools, their overall reliability differs between readability (high) and understandability (low). Approaches combining multiple assessment tools and involving both quantitative and qualitative observations would optimize assessment strategies. Effective assessment of online health information should rely on mixed strategies combining quantitative and qualitative evaluations. Assessment tools should be selected according to their functional properties and compatibility with target material. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.
... Time and International Normalized Ratio (PT/INR) PSEN1 Quantitative Immunoglobulins Red Blood Cell (RBC) Antibody Identification Red ... by a number of conditions other than malnutrition. Research is continuing in order to better understand the ...
Rohrbaugh, Michael J
2014-09-01
Social cybernetic (systemic) ideas from the early Family Process era, though emanating from qualitative clinical observation, have underappreciated heuristic potential for guiding quantitative empirical research on problem maintenance and change. The old conceptual wines we have attempted to repackage in new, science-friendly bottles include ironic processes (when "solutions" maintain problems), symptom-system fit (when problems stabilize relationships), and communal coping (when we-ness helps people change). Both self-report and observational quantitative methods have been useful in tracking these phenomena, and together the three constructs inform a team-based family consultation approach to working with difficult health and behavior problems. In addition, a large-scale, quantitatively focused effectiveness trial of family therapy for adolescent drug abuse highlights the importance of treatment fidelity and qualitative approaches to examining it. In this sense, echoing the history of family therapy research, our experience with juxtaposing quantitative and qualitative methods has gone full circle-from qualitative to quantitative observation and back again. © 2014 FPI, Inc.
Rohrbaugh, Michael J.
2015-01-01
Social cybernetic (systemic) ideas from the early Family Process era, though emanating from qualitative clinical observation, have underappreciated heuristic potential for guiding quantitative empirical research on problem maintenance and change. The old conceptual wines we have attempted to repackage in new, science-friendly bottles include ironic processes (when “solutions” maintain problems), symptom-system fit (when problems stabilize relationships), and communal coping (when we-ness helps people change). Both self-report and observational quantitative methods have been useful in tracking these phenomena, and together the three constructs inform a team-based family consultation (FAMCON) approach to working with difficult health and behavior problems. In addition, a large-scale, quantitatively focused effectiveness trial of family therapy for adolescent drug abuse highlights the importance of treatment fidelity and qualitative approaches to examining it. In this sense, echoing the history of family therapy research, our experience with juxtaposing quantitative and qualitative methods has gone full circle – from qualitative to quantitative observation and back again. PMID:24905101
Du, Qingzhang; Tian, Jiaxing; Yang, Xiaohui; Pan, Wei; Xu, Baohua; Li, Bailian; Ingvarsson, Pär K.; Zhang, Deqiang
2015-01-01
Economically important traits in many species generally show polygenic, quantitative inheritance. The components of genetic variation (additive, dominant and epistatic effects) of these traits conferred by multiple genes in shared biological pathways remain to be defined. Here, we investigated 11 full-length genes in cellulose biosynthesis, on 10 growth and wood-property traits, within a population of 460 unrelated Populus tomentosa individuals, via multi-gene association. To validate positive associations, we conducted single-marker analysis in a linkage population of 1,200 individuals. We identified 118, 121, and 43 associations (P< 0.01) corresponding to additive, dominant, and epistatic effects, respectively, with low to moderate proportions of phenotypic variance (R2). Epistatic interaction models uncovered a combination of three non-synonymous sites from three unique genes, representing a significant epistasis for diameter at breast height and stem volume. Single-marker analysis validated 61 associations (false discovery rate, Q ≤ 0.10), representing 38 SNPs from nine genes, and its average effect (R2 = 3.8%) nearly 2-fold higher than that identified with multi-gene association, suggesting that multi-gene association can capture smaller individual variants. Moreover, a structural gene–gene network based on tissue-specific transcript abundances provides a better understanding of the multi-gene pathway affecting tree growth and lignocellulose biosynthesis. Our study highlights the importance of pathway-based multiple gene associations to uncover the nature of genetic variance for quantitative traits and may drive novel progress in molecular breeding. PMID:25428896
THz Imaging of Skin Burn: Seeing the Unseen—An Overview
Dutta, Moumita; Bhalla, Amar S.; Guo, Ruyan
2016-01-01
Significance: This review article puts together all the studies performed so far in realizing terahertz (THz) spectra as a probing mechanism for burn evaluation, summarizing their experimental conditions, observations, outcomes, merits, and demerits, along with a comparative discussion of other currently used technologies to present the state of art in a condensed manner. The key features of this noncontact investigation technique like its precise burn depth analysis and the approaches it follows to convert the probed data into a quantitative measure have also been discussed in this article. Recent Advances: The current research developments in THz regime observed in device design technologies (like THz time domain spectrometer, quantum cascade THz lasers, THz single-photon detectors, etc.) and in understanding its unique properties (like nonionizing nature, penetrability through dry dielectrics, etc.) have motivated the research world to realize THz window as a potential candidate for burn detection. Critical Issues: Application of appropriate medical measure for burn injury is primarily subjective to proper estimation of burn depth. Tool modality distinguishing between partial and full-thickness burn contributing toward correct medical care is indeed awaited. Future Directions: The overview of THz imaging as a burn assessment tool as provided in this article will certainly help in further nurturing of this emerging diagnostic technique particularly in improving its detection and accompanied image processing methods so that the minute nuances captured by the THz beam can be correlated with the physiological–anatomical changes in skin structures, caused by burn, for better sensitivity, resolution, and quantitative analysis. PMID:27602253
West, Suzanne L; Squiers, Linda B; McCormack, Lauren; Southwell, Brian G; Brouwer, Emily S; Ashok, Mahima; Lux, Linda; Boudewyns, Vanessa; O'Donoghue, Amie; Sullivan, Helen W
2013-05-01
Under the Food, Drug, and Cosmetic Act, all promotional materials for prescription drugs must strike a fair balance in presentation of risks and benefits. How to best present this information is not clear. We sought to determine if the presentation of quantitative risk and benefit information in drug advertising and labeling influences consumers', patients', and clinicians' information processing, knowledge, and behavior by assessing available empirical evidence. We used PubMed for a literature search, limiting to articles published in English from 1990 forward. Two reviewers independently reviewed the titles and abstracts for inclusion, after which we reviewed the full texts to determine if they communicated risk/benefit information either: (i) numerically (e.g., percent) versus non-numerically (e.g., using text such as "increased risk") or (ii) numerically using different formats (e.g., "25% of patients", "one in four patients", or use of pictographs). We abstracted information from included articles into standardized evidence tables. The research team identified a total of 674 relevant publications, of which 52 met our inclusion criteria. Of these, 37 focused on drugs. Presenting numeric information appears to improve understanding of risks and benefits relative to non-numeric presentation; presenting both numeric and non-numeric information when possible may be best practice. No single specific format or graphical approach emerged as consistently superior. Numeracy and health literacy also deserve more empirical attention as moderators. Copyright © 2013 John Wiley & Sons, Ltd.
Automatic thermographic scanning with the creation of 3D panoramic views of buildings
NASA Astrophysics Data System (ADS)
Ferrarini, G.; Cadelano, G.; Bortolin, A.
2016-05-01
Infrared thermography is widely applied to the inspection of building, enabling the identification of thermal anomalies due to the presence of hidden structures, air leakages, and moisture. One of the main advantages of this technique is the possibility to acquire rapidly a temperature map of a surface. However, due to the actual low-resolution of thermal camera and the necessity of scanning surfaces with different orientation, during a building survey it is necessary to take multiple images. In this work a device based on quantitative infrared thermography, called aIRview, has been applied during building surveys to automatically acquire thermograms with a camera mounted on a robotized pan tilt unit. The goal is to perform a first rapid survey of the building that could give useful information for the successive quantitative thermal investigations. For each data acquisition, the instrument covers a rotational field of view of 360° around the vertical axis and up to 180° around the horizontal one. The obtained images have been processed in order to create a full equirectangular projection of the ambient. For this reason the images have been integrated into a web visualization tool, working with web panorama viewers such as Google Street View, creating a webpage where it is possible to have a three dimensional virtual visit of the building. The thermographic data are embedded with the visual imaging and with other sensor data, facilitating the understanding of the physical phenomena underlying the temperature distribution.
Bok, Jin Mo; Bae, Jong Ju; Choi, Han-Yong; Varma, Chandra M.; Zhang, Wentao; He, Junfeng; Zhang, Yuxiao; Yu, Li; Zhou, X. J.
2016-01-01
A profound problem in modern condensed matter physics is discovering and understanding the nature of fluctuations and their coupling to fermions in cuprates, which lead to high-temperature superconductivity and the invariably associated strange metal state. We report the quantitative determination of normal and pairing self-energies, made possible by laser-based angle-resolved photoemission measurements of unprecedented accuracy and stability. Through a precise inversion procedure, both the effective interactions in the attractive d-wave symmetry and the repulsive part in the full symmetry are determined. The latter is nearly angle-independent. Near Tc, both interactions are nearly independent of frequency and have almost the same magnitude over the complete energy range of up to about 0.4 eV, except for a low-energy feature at around 50 meV that is present only in the repulsive part, which has less than 10% of the total spectral weight. Well below Tc, they both change similarly, with superconductivity-induced features at low energies. Besides finding the pairing self-energy and the attractive interactions for the first time, these results expose the central paradox of the problem of high Tc: how the same frequency-independent fluctuations can dominantly scatter at angles ±π/2 in the attractive channel to give d-wave pairing and lead to angle-independent repulsive scattering. The experimental results are compared with available theoretical calculations based on antiferromagnetic fluctuations, the Hubbard model, and quantum-critical fluctuations of the loop-current order. PMID:26973872
Zheng, Dehong; Yao, Xiaoyan; Duan, Meng; Luo, Yufeng; Liu, Biao; Qi, Pengyuan; Sun, Ming; Ruan, Lifang
2016-01-01
Two-component signal transduction systems (TCSs) are widely used by bacteria to adapt to the environment. In the present study, StoS (stress tolerance-related oxygen sensor) and SreKRS (salt response kinase, regulator, and sensor) were found to positively regulate extracellular polysaccharide (EPS) production and swarming in the rice pathogen Xanthomonas oryzae pv. oryzae (Xoo). Surprisingly, the absence of stoS or sreKRS did not attenuate virulence. To better understand the intrinsic functions of StoS and SreKRS, quantitative proteomics isobaric tags for relative and absolute quantitation (iTRAQ) was employed. Consistent with stoS and sreK mutants exhibiting a similar phenotype, the signalling circuits of StoS and SreKRS overlapped. Carbohydrate metabolism proteins and chemotaxis proteins, which could be responsible for EPS and swarming regulation, respectively, were reprogrammed in stoS and sreK mutants. Moreover, StoS and SreKRS demonstrated moderate expression of the major virulence factor, hypersensitive response and pathogenicity (Hrp) proteins through the HrpG-HrpX circuit. Most importantly, Xoo equipped with StoS and SreKRS outcompetes strains without StoS or SreKRS in co-infected rice and grows outside the host. Therefore, we propose that StoS and SreKRS adopt a novel strategy involving the moderation of Hrp protein expression and the promotion of EPS and motility to adapt to the environment. PMID:26957113
Unternaehrer, E; Luers, P; Mill, J; Dempster, E; Meyer, A H; Staehli, S; Lieb, R; Hellhammer, D H; Meinlschmidt, G
2012-08-14
Environmentally induced epigenetic alterations are related to mental health. We investigated quantitative DNA methylation status before and after an acute psychosocial stressor in two stress-related genes: oxytocin receptor (OXTR) and brain-derived neurotrophic factor (BDNF ). The cross sectional study took place at the Division of Theoretical and Clinical Psychobiology, University of Trier, Germany and was conducted from February to August 2009. We included 83 participants aged 61-67 years. Thereof, 76 participants completed the full study procedure consisting of blood sampling before (pre-stress), 10 min after (post-stress) and 90 min after (follow-up) the Trier social stress test. We assessed quantitative DNA methylation of whole-blood cells using Sequenom EpiTYPER. Methylation status differed between sampling times in one target sequence of OXTR (P<0.001): methylation increased from pre- to post-stress (P=0.009) and decreased from post-stress to follow-up (P<0.001). This decrease was also found in a second target sequence of OXTR (P=0.034), where it lost statistical significance when blood cell count was statistically controlled. We did not detect any time-associated differences in methylation status of the examined BDNF region. The results suggest a dynamic regulation of DNA methylation in OXTR-which may in part reflect changes in blood cell composition-but not BDNF after acute psychosocial stress. This may enhance the understanding of how psychosocial events alter DNA methylation and could provide new insights into the etiology of mental disorders.
Kubota, Ken J; Chen, Jason A; Little, Max A
2016-09-01
For the treatment and monitoring of Parkinson's disease (PD) to be scientific, a key requirement is that measurement of disease stages and severity is quantitative, reliable, and repeatable. The last 50 years in PD research have been dominated by qualitative, subjective ratings obtained by human interpretation of the presentation of disease signs and symptoms at clinical visits. More recently, "wearable," sensor-based, quantitative, objective, and easy-to-use systems for quantifying PD signs for large numbers of participants over extended durations have been developed. This technology has the potential to significantly improve both clinical diagnosis and management in PD and the conduct of clinical studies. However, the large-scale, high-dimensional character of the data captured by these wearable sensors requires sophisticated signal processing and machine-learning algorithms to transform it into scientifically and clinically meaningful information. Such algorithms that "learn" from data have shown remarkable success in making accurate predictions for complex problems in which human skill has been required to date, but they are challenging to evaluate and apply without a basic understanding of the underlying logic on which they are based. This article contains a nontechnical tutorial review of relevant machine-learning algorithms, also describing their limitations and how these can be overcome. It discusses implications of this technology and a practical road map for realizing the full potential of this technology in PD research and practice. © 2016 International Parkinson and Movement Disorder Society. © 2016 International Parkinson and Movement Disorder Society.
THz Imaging of Skin Burn: Seeing the Unseen-An Overview.
Dutta, Moumita; Bhalla, Amar S; Guo, Ruyan
2016-08-01
Significance: This review article puts together all the studies performed so far in realizing terahertz (THz) spectra as a probing mechanism for burn evaluation, summarizing their experimental conditions, observations, outcomes, merits, and demerits, along with a comparative discussion of other currently used technologies to present the state of art in a condensed manner. The key features of this noncontact investigation technique like its precise burn depth analysis and the approaches it follows to convert the probed data into a quantitative measure have also been discussed in this article. Recent Advances: The current research developments in THz regime observed in device design technologies (like THz time domain spectrometer, quantum cascade THz lasers, THz single-photon detectors, etc.) and in understanding its unique properties (like nonionizing nature, penetrability through dry dielectrics, etc.) have motivated the research world to realize THz window as a potential candidate for burn detection. Critical Issues: Application of appropriate medical measure for burn injury is primarily subjective to proper estimation of burn depth. Tool modality distinguishing between partial and full-thickness burn contributing toward correct medical care is indeed awaited. Future Directions: The overview of THz imaging as a burn assessment tool as provided in this article will certainly help in further nurturing of this emerging diagnostic technique particularly in improving its detection and accompanied image processing methods so that the minute nuances captured by the THz beam can be correlated with the physiological-anatomical changes in skin structures, caused by burn, for better sensitivity, resolution, and quantitative analysis.
Evaluation of Historical and Projected Agricultural Climate Risk Over the Continental US
NASA Astrophysics Data System (ADS)
Zhu, X.; Troy, T. J.; Devineni, N.
2016-12-01
Food demands are rising due to an increasing population with changing food preferences, which places pressure on agricultural systems. In addition, in the past decade climate extremes have highlighted the vulnerability of our agricultural production to climate variability. Quantitative analyses in the climate-agriculture research field have been performed in many studies. However, climate risk still remains difficult to evaluate at large scales yet shows great potential of help us better understand historical climate change impacts and evaluate the future risk given climate projections. In this study, we developed a framework to evaluate climate risk quantitatively by applying statistical methods such as Bayesian regression, distribution fitting, and Monte Carlo simulation. We applied the framework over different climate regions in the continental US both historically and for modeled climate projections. The relative importance of any major growing season climate index, such as maximum dry period or heavy precipitation, was evaluated to determine what climate indices play a role in affecting crop yields. The statistical modeling framework was applied using county yields, with irrigated and rainfed yields separated to evaluate the different risk. This framework provides estimates of the climate risk facing agricultural production in the near-term that account for the full uncertainty of climate occurrences, range of crop response, and spatial correlation in climate. In particular, the method provides robust estimates of importance of irrigation in mitigating agricultural climate risk. The results of this study can contribute to decision making about crop choice and water use in an uncertain climate.
Holzweber, Markus; Lippitz, Andreas; Krueger, Katharina; Jankowski, Joachim; Unger, Wolfgang E. S.
2015-01-01
The surfaces of polymeric dialyzer membranes consisting of polysulfone and poly-vinylpyrrolidone were investigated regarding the lateral distribution and quantitative surface composition using time-of-flight secondary-ion-mass-spectrometry and x-ray photoelectron spectroscopy. Knowledge of the distribution and composition on the outer surface region is of utmost importance for understanding the biocompatibility of such dialyzer membranes. Both flat membranes and hollow fiber membranes were studied. PMID:25711334
1988-02-01
quantitatively miror pathway. Only two of the enzymes which process 8-endorphin have been firmly identified, peptide acetyltransferase and... quantitatively minor. This implied that perhaps peptide acetyltransferase is not a critical determinant of the bioactivity of B-endorphin in brain. If so...provided us with a more difinitive understanding of the role of processing enzyme regulation in the overall biochemical and cellular response of the
2016-01-05
is we made progress, ex post facto , in terms of methodology development towards what DARPA recently called for, namely “improve[ing] our understanding...for their bases of activity. Prior quantitative research , by the P.I. and by others, has shown that tribalism is an important incubator of Islamist...undergraduate students partook in the research , and were involved in conceptualization of problems, quantitative and qualitative research , coding of
NASA Astrophysics Data System (ADS)
Biswas, Deblina; Vasudevan, Srivathsan; Chen, George C. K.; Sharma, Norman
2017-02-01
Formation of blood clots, called thrombus, can happen due to hyper-coagulation of blood. Thrombi, while moving through blood vessels can impede blood flow, an important criterion for many critical diseases like deep vein thrombosis and heart attacks. Understanding mechanical properties of clot formation is vital for assessment of severity of thrombosis and proper treatment. However, biomechanics of thrombus is less known to clinicians and not very well investigated. Photoacoustic (PA) spectral response, a non-invasive technique, is proposed to investigate the mechanism of formation of blood clots through elasticity and also differentiate clots from blood. Distinct shift (increase in frequency) of the PA response dominant frequency during clot formation is reported. In addition, quantitative differentiation of blood clots from blood has been achieved through parameters like dominant frequency and spectral energy of PA spectral response. Nearly twofold increases in dominant frequency in blood clots compared to blood were found in the PA spectral response. Significant changes in energy also help in quantitatively differentiating clots from blood, in the blood. Our results reveal that increase in density during clot formation is reflected in the PA spectral response, a significant step towards understanding the mechanobiology of thrombus formation. Hence, the proposed tool, in addition to detecting thrombus formation, could reveal mechanical properties of the sample through quantitative photoacoustic spectral parameters.
Liu, Yan; Song, Yang; Madahar, Vipul; Liao, Jiayu
2012-03-01
Förster resonance energy transfer (FRET) technology has been widely used in biological and biomedical research, and it is a very powerful tool for elucidating protein interactions in either dynamic or steady state. SUMOylation (the process of SUMO [small ubiquitin-like modifier] conjugation to substrates) is an important posttranslational protein modification with critical roles in multiple biological processes. Conjugating SUMO to substrates requires an enzymatic cascade. Sentrin/SUMO-specific proteases (SENPs) act as an endopeptidase to process the pre-SUMO or as an isopeptidase to deconjugate SUMO from its substrate. To fully understand the roles of SENPs in the SUMOylation cycle, it is critical to understand their kinetics. Here, we report a novel development of a quantitative FRET-based protease assay for SENP1 kinetic parameter determination. The assay is based on the quantitative analysis of the FRET signal from the total fluorescent signal at acceptor emission wavelength, which consists of three components: donor (CyPet-SUMO1) emission, acceptor (YPet) emission, and FRET signal during the digestion process. Subsequently, we developed novel theoretical and experimental procedures to determine the kinetic parameters, k(cat), K(M), and catalytic efficiency (k(cat)/K(M)) of catalytic domain SENP1 toward pre-SUMO1. Importantly, the general principles of this quantitative FRET-based protease kinetic determination can be applied to other proteases. Copyright © 2011 Elsevier Inc. All rights reserved.
Using mixed methods when researching communities.
Ochieng, Bertha M N; Meetoo, Danny
2015-09-01
To argue for the use of mixed methods when researching communities. Although research involving minority communities is now advanced, not enough effort has been made to formulate methodological linkages between qualitative and quantitative methods in most studies. For instance, the quantitative approaches used by epidemiologists and others in examining the wellbeing of communities are usually empirical. While the rationale for this is sound, quantitative findings can be expanded with data from in-depth qualitative approaches, such as interviews or observations, which are likely to provide insights into the experiences of people in those communities and their relationships with their wellbeing. Academic databases including The Cochrane Library, MEDLINE, CINAHL, AMED, INTERNURSE, Science Direct, Web of Knowledge and PubMed. An iterative process of identifying eligible literature was carried out by comprehensively searching electronic databases. Using mixed-methods approaches is likely to address any potential drawbacks of individual methods by exploiting the strengths of each at the various stages of research. Combining methods can provide additional ways of looking at a complex problem and improve the understanding of a community's experiences. However, it is important for researchers to use the different methods interactively during their research. The use of qualitative and quantitative methods is likely to enrich our understanding of the interrelationship between wellbeing and the experiences of communities. This should help researchers to explore socio-cultural factors and experiences of health and healthcare practice more effectively.
Sun, Tie Gang; Xiao, Rong Bo; Cai, Yun Nan; Wang, Yao Wu; Wu, Chang Guang
2016-08-01
Quantitative assessment of urban thermal environment has become a focus for urban climate and environmental science since the concept of urban heat island has been proposed. With the continual development of space information and computer simulation technology, substantial progresses have been made on quantitative assessment techniques and methods of urban thermal environment. The quantitative assessment techniques have been developed to dynamics simulation and forecast of thermal environment at various scales based on statistical analysis of thermal environment on urban-scale using the historical data of weather stations. This study reviewed the development progress of ground meteorological observation, thermal infrared remote sensing and numerical simulation. Moreover, the potential advantages and disadvantages, applicability and the development trends of these techniques were also summarized, aiming to add fundamental knowledge of understanding the urban thermal environment assessment and optimization.
Rethinking health numeracy: a multidisciplinary literature review.
Ancker, Jessica S; Kaufman, David
2007-01-01
The purpose of this review is to organize various published conceptions of health numeracy and to discuss how health numeracy contributes to the productive use of quantitative information for health. We define health numeracy as the individual-level skills needed to understand and use quantitative health information, including basic computation skills, ability to use information in documents and non-text formats such as graphs, and ability to communicate orally. We also identify two other factors affecting whether a consumer can use quantitative health information: design of documents and other information artifacts, and health-care providers' communication skills. We draw upon the distributed cognition perspective to argue that essential ingredients for the productive use of quantitative health information include not only health numeracy but also good provider communication skills, as well as documents and devices that are designed to enhance comprehension and cognition.
Takamatsu, Daiko; Yoneyama, Akio; Asari, Yusuke; Hirano, Tatsumi
2018-02-07
A fundamental understanding of concentrations of salts in lithium-ion battery electrolytes during battery operation is important for optimal operation and design of lithium-ion batteries. However, there are few techniques that can be used to quantitatively characterize salt concentration distributions in the electrolytes during battery operation. In this paper, we demonstrate that in operando X-ray phase imaging can quantitatively visualize the salt concentration distributions that arise in electrolytes during battery operation. From quantitative evaluation of the concentration distributions at steady states, we obtained the salt diffusivities in electrolytes with different initial salt concentrations. Because of no restriction on samples and high temporal and spatial resolutions, X-ray phase imaging will be a versatile technique for evaluating electrolytes, both aqueous and nonaqueous, of many electrochemical systems.
Thompson, Debbe; Power, Thomas G.; Hughes, Sheryl O.
2015-01-01
Abstract Background: This study examined maternal understanding and acceptance of young children's ability to self-assess fullness using a mixed-methods approach. Methods: Twenty low-income mothers of 5- to 7-year-olds participated in this semistructured laboratory study. After consumption of a buffet dinner meal, mothers were asked to indicate their perception of their child's fullness level, and children were also asked to self-assess their fullness level. Results: Five of the 20 mothers in the study were initially correct in their assessment of their child's level of fullness. Half of the incorrect mothers were willing to change their rating when informed that the child's fullness rating was different than her own. Conclusions: Semistructured interview results provide suggestive evidence that some mothers believe they understand their child's fullness level better than their children. Given that mothers have the potential to override children's ability to self-regulate eating behavior, teaching mothers to understand and appreciate young children's ability to self-regulate eating is an important area for intervention. PMID:25692707
Quantitation of Met tyrosine phosphorylation using MRM-MS.
Meng, Zhaojing; Srivastava, Apurva K; Zhou, Ming; Veenstra, Timothy
2013-01-01
Phosphorylation has long been accepted as a key cellular regulator of cell signaling pathways. The recent development of multiple-reaction monitoring mass spectrometry (MRM-MS) provides a useful tool for measuring the absolute quantity of phosphorylation occupancy at pivotal sites within signaling proteins, even when the phosphorylation sites are in close proximity. Here, we described a targeted quantitation approach to measure the absolute phosphorylation occupancy at Y1234 and Y1235 of Met. The approach is utilized to obtain absolute occupancy of the two phosphorylation sites in the full-length recombinant Met. It is further applied to quantitate the phosphorylation state of these two sites in SNU-5 cells treated with a Met inhibitor.
Flipping interferometry and its application for quantitative phase microscopy in a micro-channel.
Roitshtain, Darina; Turko, Nir A; Javidi, Bahram; Shaked, Natan T
2016-05-15
We present a portable, off-axis interferometric module for quantitative phase microscopy of live cells, positioned at the exit port of a coherently illuminated inverted microscope. The module creates on the digital camera an interference pattern between the image of the sample and its flipped version. The proposed simplified module is based on a retro-reflector modification in an external Michelson interferometer. The module does not contain any lenses, pinholes, or gratings and its alignment is straightforward. Still, it allows full control of the off-axis angle and does not suffer from ghost images. As experimentally demonstrated, the module is useful for quantitative phase microscopy of live cells rapidly flowing in a micro-channel.
Combustion Processes in Hybrid Rocket Engines
NASA Technical Reports Server (NTRS)
Venkateswaran,S.; Merkle, C. L.
1996-01-01
In recent years, there has been a resurgence of interest in the development of hybrid rocket engines for advanced launch vehicle applications. Hybrid propulsion systems use a solid fuel such as hydroxyl-terminated polybutadiene (HTPB) along with a gaseous/liquid oxidizer. The performance of hybrid combustors depends on the convective and radiative heat fluxes to the fuel surface, the rate of pyrolysis in the solid phase, and the turbulent combustion processes in the gaseous phases. These processes in combination specify the regression rates of the fuel surface and thereby the utilization efficiency of the fuel. In this paper, we employ computational fluid dynamics (CFD) techniques in order to gain a quantitative understanding of the physical trends in hybrid rocket combustors. The computational modeling is tailored to ongoing experiments at Penn State that employ a two dimensional slab burner configuration. The coordinated computational/experimental effort enables model validation while providing an understanding of the experimental observations. Computations to date have included the full length geometry with and with the aft nozzle section as well as shorter length domains for extensive parametric characterization. HTPB is sed as the fuel with 1,3 butadiene being taken as the gaseous product of the pyrolysis. Pure gaseous oxygen is taken as the oxidizer. The fuel regression rate is specified using an Arrhenius rate reaction, which the fuel surface temperature is given by an energy balance involving gas-phase convection and radiation as well as thermal conduction in the solid-phase. For the gas-phase combustion, a two step global reaction is used. The standard kappa - epsilon model is used for turbulence closure. Radiation is presently treated using a simple diffusion approximation which is valid for large optical path lengths, representative of radiation from soot particles. Computational results are obtained to determine the trends in the fuel burning or regression rates as a function of the head-end oxidizer mass flux, G=rho(e)U(e), and the chamber pressure. Furthermore, computation of the full slab burner configuration has also been obtained for various stages of the burn. Comparisons with available experimental data from small scale tests conducted by General Dynamics-Thiokol-Rocketdyne suggest reasonable agreement in the predicted regression rates. Future work will include: (1) a model for soot generation in the flame for more quantitative radiative transfer modelling, (2) a parametric study of combustion efficiency, and (3) transient calculations to help determine the possible mechanisms responsible for combustion instability in hybrid rocket motors.
A Computational Model of Liver Iron Metabolism
Mitchell, Simon; Mendes, Pedro
2013-01-01
Iron is essential for all known life due to its redox properties; however, these same properties can also lead to its toxicity in overload through the production of reactive oxygen species. Robust systemic and cellular control are required to maintain safe levels of iron, and the liver seems to be where this regulation is mainly located. Iron misregulation is implicated in many diseases, and as our understanding of iron metabolism improves, the list of iron-related disorders grows. Recent developments have resulted in greater knowledge of the fate of iron in the body and have led to a detailed map of its metabolism; however, a quantitative understanding at the systems level of how its components interact to produce tight regulation remains elusive. A mechanistic computational model of human liver iron metabolism, which includes the core regulatory components, is presented here. It was constructed based on known mechanisms of regulation and on their kinetic properties, obtained from several publications. The model was then quantitatively validated by comparing its results with previously published physiological data, and it is able to reproduce multiple experimental findings. A time course simulation following an oral dose of iron was compared to a clinical time course study and the simulation was found to recreate the dynamics and time scale of the systems response to iron challenge. A disease state simulation of haemochromatosis was created by altering a single reaction parameter that mimics a human haemochromatosis gene (HFE) mutation. The simulation provides a quantitative understanding of the liver iron overload that arises in this disease. This model supports and supplements understanding of the role of the liver as an iron sensor and provides a framework for further modelling, including simulations to identify valuable drug targets and design of experiments to improve further our knowledge of this system. PMID:24244122
MO-G-12A-01: Quantitative Imaging Metrology: What Should Be Assessed and How?
DOE Office of Scientific and Technical Information (OSTI.GOV)
Giger, M; Petrick, N; Obuchowski, N
The first two symposia in the Quantitative Imaging Track focused on 1) the introduction of quantitative imaging (QI) challenges and opportunities, and QI efforts of agencies and organizations such as the RSNA, NCI, FDA, and NIST, and 2) the techniques, applications, and challenges of QI, with specific examples from CT, PET/CT, and MR. This third symposium in the QI Track will focus on metrology and its importance in successfully advancing the QI field. While the specific focus will be on QI, many of the concepts presented are more broadly applicable to many areas of medical physics research and applications. Asmore » such, the topics discussed should be of interest to medical physicists involved in imaging as well as therapy. The first talk of the session will focus on the introduction to metrology and why it is critically important in QI. The second talk will focus on appropriate methods for technical performance assessment. The third talk will address statistically valid methods for algorithm comparison, a common problem not only in QI but also in other areas of medical physics. The final talk in the session will address strategies for publication of results that will allow statistically valid meta-analyses, which is critical for combining results of individual studies with typically small sample sizes in a manner that can best inform decisions and advance the field. Learning Objectives: Understand the importance of metrology in the QI efforts. Understand appropriate methods for technical performance assessment. Understand methods for comparing algorithms with or without reference data (i.e., “ground truth”). Understand the challenges and importance of reporting results in a manner that allows for statistically valid meta-analyses.« less
Optical Ptychographic Microscope for Quantitative Bio-Mechanical Imaging
NASA Astrophysics Data System (ADS)
Anthony, Nicholas; Cadenazzi, Guido; Nugent, Keith; Abbey, Brian
The role that mechanical forces play in biological processes such as cell movement and death is becoming of significant interest to further develop our understanding of the inner workings of cells. The most common method used to obtain stress information is photoelasticity which maps a samples birefringence, or its direction dependent refractive indices, using polarized light. However this method only provides qualitative data and for stress information to be useful quantitative data is required. Ptychography is a method for quantitatively determining the phase of a samples complex transmission function. The technique relies upon the collection of multiple overlapping coherent diffraction patterns from laterally displaced points on the sample. The overlap of measurement points provides complementary information that significantly aids in the reconstruction of the complex wavefield exiting the sample and allows for quantitative imaging of weakly interacting specimens. Here we describe recent advances at La Trobe University Melbourne on achieving quantitative birefringence mapping using polarized light ptychography with applications in cell mechanics. Australian Synchrotron, ARC Centre of Excellence for Advanced Molecular Imaging.
FRONTIER FIELDS: HIGH-REDSHIFT PREDICTIONS AND EARLY RESULTS
DOE Office of Scientific and Technical Information (OSTI.GOV)
Coe, Dan; Bradley, Larry; Zitrin, Adi, E-mail: DCoe@STScI.edu
2015-02-20
The Frontier Fields program is obtaining deep Hubble and Spitzer Space Telescope images of new ''blank'' fields and nearby fields gravitationally lensed by massive galaxy clusters. The Hubble images of the lensed fields are revealing nJy sources (AB mag > 31), the faintest galaxies yet observed. The full program will transform our understanding of galaxy evolution in the first 600 million years (z > 9). Previous programs have yielded a dozen or so z > 9 candidates, including perhaps fewer than expected in the Ultra Deep Field and more than expected in shallower Hubble images. In this paper, we present high-redshift (z >more » 6) number count predictions for the Frontier Fields and candidates in three of the first Hubble images. We show the full Frontier Fields program may yield up to ∼70 z > 9 candidates (∼6 per field). We base this estimate on an extrapolation of luminosity functions observed between 4 < z < 8 and gravitational lensing models submitted by the community. However, in the first two deep infrared Hubble images obtained to date, we find z ∼ 8 candidates but no strong candidates at z > 9. We defer quantitative analysis of the z > 9 deficit (including detection completeness estimates) to future work including additional data. At these redshifts, cosmic variance (field-to-field variation) is expected to be significant (greater than ±50%) and include clustering of early galaxies formed in overdensities. The full Frontier Fields program will significantly mitigate this uncertainty by observing six independent sightlines each with a lensing cluster and nearby blank field.« less
Damage Assessment of a Full-Scale Six-Story wood-frame Building Following Triaxial shake Table Tests
John W. van de Lindt; Rakesh Gupta; Shiling Pei; Kazuki Tachibana; Yasuhiro Araki; Douglas Rammer; Hiroshi Isoda
2012-01-01
In the summer of 2009, a full-scale midrise wood-frame building was tested under a series of simulated earthquakes on the world's largest shake table in Miki City, Japan. The objective of this series of tests was to validate a performance-based seismic design approach by qualitatively and quantitatively examining the building's seismic performance in terms of...
Method for the Simultaneous Quantitation of Apolipoprotein E Isoforms using Tandem Mass Spectrometry
Wildsmith, Kristin R.; Han, Bomie; Bateman, Randall J.
2009-01-01
Using Apolipoprotein E (ApoE) as a model protein, we developed a protein isoform analysis method utilizing Stable Isotope Labeling Tandem Mass Spectrometry (SILT MS). ApoE isoforms are quantitated using the intensities of the b and y ions of the 13C-labeled tryptic isoform-specific peptides versus unlabeled tryptic isoform-specific peptides. The ApoE protein isoform analysis using SILT allows for the simultaneous detection and relative quantitation of different ApoE isoforms from the same sample. This method provides a less biased assessment of ApoE isoforms compared to antibody-dependent methods, and may lead to a better understanding of the biological differences between isoforms. PMID:19653990
The use of behavioural theories in end-of-life care research: A systematic review.
Scherrens, Anne-Lore; Beernaert, Kim; Robijn, Lenzo; Deliens, Luc; Pauwels, Nele S; Cohen, Joachim; Deforche, Benedicte
2018-06-01
It is necessary to understand behaviours that contribute to improvement in the quality of end-of-life care; use of behavioural theories allows identification of factors underlying end-of-life care behaviour, but little is known about the extent to which, and in what manner, these theories are used in an end-of-life care research context. To assess the number of end-of-life care studies that have used behavioural theories, which theories were used, to what extent main constructs were explored/measured and which behavioural outcomes were examined. We conducted a systematic review. The protocol was registered on PROSPERO (CRD42016036009). The MEDLINE (PubMed), PsycINFO, EMBASE, Web of Science and CINAHL databases were searched from inception to June 2017. We included studies aimed at understanding or changing end-of-life care behaviours and that explicitly referred to individual behavioural theories. We screened 2231 records by title and abstract, retrieved 43 full-text articles and included 31 studies - 27 quantitative (of which four (quasi-)randomised controlled trials) and four qualitative - for data extraction. More than half used the Theory of Planned Behaviour (9), the Theory of Reasoned Action (4) or the Transtheoretical Model (8). In 9 of 31 studies, the theory was fully used, and 16 of the 31 studies focussed on behaviours in advance care planning. In end-of-life care research, the use of behavioural theories is limited. As many behaviours can determine the quality of care, their more extensive use may be warranted if we want to better understand and influence behaviours and improve end-of-life care.
Catalysts at work: From integral to spatially resolved X-ray absorption spectroscopy
DOE Office of Scientific and Technical Information (OSTI.GOV)
Grunwaldt, Jan-Dierk; Kimmerle, Bertram; Baiker, Alfons
2009-09-25
Spectroscopic studies on heterogeneous catalysts have mostly been done in an integral mode. However, in many cases spatial variations in catalyst structure can occur, e.g. during impregnation of pre-shaped particles, during reaction in a catalytic reactor, or in microstructured reactors as the present overview shows. Therefore, spatially resolved molecular information on a microscale is required for a comprehensive understanding of theses systems, partly in ex situ studies, partly under stationary reaction conditions and in some cases even under dynamic reaction conditions. Among the different available techniques, X-ray absorption spectroscopy (XAS) is a well-suited tool for this purpose as the differentmore » selected examples highlight. Two different techniques, scanning and full-field X-ray microscopy/tomography, are described and compared. At first, the tomographic structure of impregnated alumina pellets is presented using full-field transmission microtomography and compared to the results obtained with a scanning X-ray microbeam technique to analyse the catalyst bed inside a catalytic quartz glass reactor. On the other hand, by using XAS in scanning microtomography, the structure and the distribution of Cu(0), Cu(I), Cu(II) species in a Cu/ZnO catalyst loaded in a quartz capillary microreactor could be reconstructed quantitatively on a virtual section through the reactor. An illustrating example for spatially resolved XAS under reaction conditions is the partial oxidation of methane over noble metal-based catalysts. In order to obtain spectroscopic information on the spatial variation of the oxidation state of the catalyst inside the reactor XAS spectra were recorded by scanning with a micro-focussed beam along the catalyst bed. Alternatively, full-field transmission imaging was used to efficiently determine the distribution of the oxidation state of a catalyst inside a reactor under reaction conditions. The new technical approaches together with quantitative data analysis and an appropriate in situ catalytic experiment allowed drawing important conclusions on the reaction mechanism, and the analytical strategy might be similarly applied in other case studies. The corresponding temperature profiles and the catalytic performance were measured by means of an IR-camera and mass spectrometric analysis. In a more advanced experiment the ignition process of the partial oxidation of methane was followed in a spatiotemporal manner which demonstrates that spatially resolved spectroscopic information can even be obtained in the subsecond scale.« less
Ramanathan, Ragu; Ghosal, Anima; Ramanathan, Lakshmi; Comstock, Kate; Shen, Helen; Ramanathan, Dil
2018-05-01
Evaluation of HPLC-high-resolution mass spectrometry (HPLC-HRMS) full scan with polarity switching for increasing throughput of human in vitro cocktail drug-drug interaction assay. Microsomal incubates were analyzed using a high resolution and high mass accuracy Q-Exactive mass spectrometer to collect integrated qualitative and quantitative (qual/quant) data. Within assay, positive-to-negative polarity switching HPLC-HRMS method allowed quantification of eight and two probe compounds in the positive and negative ionization modes, respectively, while monitoring for LOR and its metabolites. LOR-inhibited CYP2C19 and showed higher activity for CYP2D6, CYP2E1 and CYP3A4. Overall, LC-HRMS-based nontargeted full scan quantitation allowed to improve the throughput of the in vitro cocktail drug-drug interaction assay.
X-ray Topographic Methods and Application to Analysis of Electronic Materials
NASA Technical Reports Server (NTRS)
Mayo, W. E.; Liu, H. Y.; Chaudhuri, J.
1984-01-01
Three supplementary X-ray techniques new to semiconductor applications are discussed. These are the Computer Aided Rocking Curve Analyzer, the Divergent Beam Method and a new method based on enhanced X-ray flourescence. The first method is used for quantitative mapping of an elastic or plastic strain field while the other two methods are used only to measure elastic strains. The divergent beam method is used for measuring the full strain tensor while the microfluorescence method is useful for monitoring strain uniformity. These methods are discussed in detail and examples of their application is presented. Among these are determination of the full strain ellipsoid in state-of-the-art liquid phase epitaxy deposited III-V epitaxial films; mapping of the plastic strain concentrations in tensile deformed Si; and quantitative determination of damage in V3Si due to ion implantation.
Prioritization methodology for chemical replacement
NASA Technical Reports Server (NTRS)
Goldberg, Ben; Cruit, Wendy; Schutzenhofer, Scott
1995-01-01
This methodology serves to define a system for effective prioritization of efforts required to develop replacement technologies mandated by imposed and forecast legislation. The methodology used is a semi quantitative approach derived from quality function deployment techniques (QFD Matrix). QFD is a conceptual map that provides a method of transforming customer wants and needs into quantitative engineering terms. This methodology aims to weight the full environmental, cost, safety, reliability, and programmatic implications of replacement technology development to allow appropriate identification of viable candidates and programmatic alternatives.
APOE Genotyping, Cardiovascular Disease
... Time and International Normalized Ratio (PT/INR) PSEN1 Quantitative Immunoglobulins Red Blood Cell (RBC) Antibody Identification Red ... tests are most often done as part of research protocols to help understand the role of genetic ...
ERIC Educational Resources Information Center
File, Carter L.
2013-01-01
This study was undertaken to understand whether a community or technical college chief business officer's career line influenced the lived experience of job satisfaction. This mixed method study was conducted in a two-phase approach using the Explanatory Design: Participant Selection Model variant. An initial quantitative survey was conducted from…
ERIC Educational Resources Information Center
Faour, Malak Abou; Ayoubi, Zalpha
2018-01-01
This study investigated the effect of using (VL) on grade 10 students' conceptual understanding of the direct current electric circuit and their attitudes towards physics. The research used a quantitative experimental approach. The sample of the study was formed of 50 students of the tenth grade, aged 14 to 16 years old, of an official secondary…
ERIC Educational Resources Information Center
Arslan Buyruk, Arzu; Ogan Bekiroglu, Feral
2018-01-01
The focus of this study was to evaluate the impact of model-based inquiry on pre-service physics teachers' conceptual understanding of dynamics. Theoretical framework of this research was based on models-of-data theory. True-experimental design using quantitative and qualitative research methods was carried out for this research. Participants of…
Low-Energy Positron-Matter Interactions Using Trap-Based Beams
2002-06-24
qualitatively by the recent exploitation of nonneutral plasma physics techniques to produce antimatter plasmas and beams in new regimes of parameter space...a quantitative antimatter - matter chemistry, important not only in obtaining a fundamental understanding of nature, but also in using antimatter in...ANNIHILATION MEASUREMENTS The fate of all antimatter in our world is annihilation with ordinary matter. Thus understanding the details of these annihilation
A Study to Understand the Role of Visual Arts in the Teaching and Learning of Science
ERIC Educational Resources Information Center
Dhanapal, Saroja; Kanapathy, Ravi; Mastan, Jamilah
2014-01-01
This research was carried out to understand the role of visual arts in the teaching and learning of science among Grade 3 teachers and students. A mixture of qualitative and quantitative research design was used to discover the different perceptions of both teachers and students on the role of visual arts in science. The data for the research was…
ERIC Educational Resources Information Center
Motala, Shireen
2006-01-01
Through an analysis of recent quantitative data on equity and school funding in South Africa, this article aims to explicate the patterns and typology of inequality in post-apartheid South Africa, and to deepen our understanding of the construct of equity. It also aims to understand the application of equity in the context of public schooling…
ERIC Educational Resources Information Center
Hock, Tan Tong; Tarmizi, Rohani Ahmad; Yunus, Aida Suraya Md.; Ayub, Ahmad Fauzi
2015-01-01
This study was conducted using a new hybrid method of research which combined qualitative and quantitative designs to investigate the viewpoints of primary school students' conceptual understanding in learning geometry from the aspect of shapes and spaces according to van Hiele theory. Q-methodology is used in this research to find out what…
Harrar, Harpal; Myers, Simon; Ghanem, Ali M
2018-02-01
Patients often seek guidance from the aesthetic practitioners regarding treatments to enhance their 'beauty'. Is there a science behind the art of assessment and if so is it measurable? Through the centuries, this question has challenged scholars, artists and surgeons. This study aims to undertake a review of the evidence behind quantitative facial measurements in assessing beauty to help the practitioner in everyday aesthetic practice. A Medline, Embase search for beauty, facial features and quantitative analysis was undertaken. Inclusion criteria were studies on adults, and exclusions included studies undertaken for dental, cleft lip, oncology, burns or reconstructive surgeries. The abstracts and papers were appraised, and further studies excluded that were considered inappropriate. The data were extracted using a standardised table. The final dataset was appraised in accordance with the PRISMA checklist and Holland and Rees' critique tools. Of the 1253 studies screened, 1139 were excluded from abstracts and a further 70 excluded from full text articles. The remaining 44 were assessed qualitatively and quantitatively. It became evident that the datasets were not comparable. Nevertheless, common themes were obvious, and these were summarised. Despite measures of the beauty of individual components to the sum of all the parts, such as symmetry and the golden ratio, we are yet far from establishing what truly constitutes quantitative beauty. Perhaps beauty is truly in the 'eyes of the beholder' (and perhaps in the eyes of the subject too). This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .
Quantitative biology of single neurons
Eberwine, James; Lovatt, Ditte; Buckley, Peter; Dueck, Hannah; Francis, Chantal; Kim, Tae Kyung; Lee, Jaehee; Lee, Miler; Miyashiro, Kevin; Morris, Jacqueline; Peritz, Tiina; Schochet, Terri; Spaethling, Jennifer; Sul, Jai-Yoon; Kim, Junhyong
2012-01-01
The building blocks of complex biological systems are single cells. Fundamental insights gained from single-cell analysis promise to provide the framework for understanding normal biological systems development as well as the limits on systems/cellular ability to respond to disease. The interplay of cells to create functional systems is not well understood. Until recently, the study of single cells has concentrated primarily on morphological and physiological characterization. With the application of new highly sensitive molecular and genomic technologies, the quantitative biochemistry of single cells is now accessible. PMID:22915636
A collection of flow visualization techniques used in the Aerodynamic Research Branch
NASA Technical Reports Server (NTRS)
1984-01-01
Theoretical and experimental research on unsteady aerodynamic flows is discussed. Complex flow fields that involve separations, vortex interactions, and transonic flow effects were investigated. Flow visualization techniques are used to obtain a global picture of the flow phenomena before detailed quantitative studies are undertaken. A wide variety of methods are used to visualize fluid flow and a sampling of these methods is presented. It is emphasized that the visualization technique is a thorough quantitative analysis and subsequent physical understanding of these flow fields.
Quantitative Analysis of Cell Nucleus Organisation
Shiels, Carol; Adams, Niall M; Islam, Suhail A; Stephens, David A; Freemont, Paul S
2007-01-01
There are almost 1,300 entries for higher eukaryotes in the Nuclear Protein Database. The proteins' subcellular distribution patterns within interphase nuclei can be complex, ranging from diffuse to punctate or microspeckled, yet they all work together in a coordinated and controlled manner within the three-dimensional confines of the nuclear volume. In this review we describe recent advances in the use of quantitative methods to understand nuclear spatial organisation and discuss some of the practical applications resulting from this work. PMID:17676980
Turning around Newton's Second Law
ERIC Educational Resources Information Center
Goff, John Eric
2004-01-01
Conceptual and quantitative difficulties surrounding Newton's second law often arise among introductory physics students. Simply turning around how one expresses Newton's second law may assist students in their understanding of a deceptively simple-looking equation.
Risks, risk assessment and risk competence in toxicology.
Stahlmann, Ralf; Horvath, Aniko
2015-01-01
Understanding the toxic effects of xenobiotics requires sound knowledge of physiology and biochemistry. The often described lack of understanding pharmacology/toxicology is therefore primarily caused by the general absence of the necessary fundamental knowledge. Since toxic effects depend on exposure (or dosage) assessing the risks arising from toxic substances also requires quantitative reasoning. Typically public discussions nearly always neglect quantitative aspects and laypersons tend to disregard dose-effect-relationships. One of the main reasons for such disregard is the fact that exposures often occur at extremely low concentrations that can only be perceived intellectually but not by the human senses. However, thresholds in the low exposure range are often scientifically disputed. At the same time, ignorance towards known dangers is wide-spread. Thus, enhancing the risk competence of laypersons will have to be initially restricted to increasing the awareness of existing problems.
NASA Technical Reports Server (NTRS)
Mungas, Greg S.; Beegle, Luther W.; Boynton, John E.; Lee, Pascal; Shidemantle, Ritch; Fisher, Ted
2004-01-01
The Camera, Hand Lens, and Microscope Probe (CHAMP) will allow examination of martian surface features and materials (terrain, rocks, soils, samples) on spatial scales ranging from kilometers to micrometers, thus enabling both microscopy and context imaging with high operational flexibility. CHAMP is designed to allow the detailed and quantitative investigation of a wide range of geologic features and processes on Mars, leading to a better quantitative understanding of the evolution of the martian surface environment through time. In particular, CHAMP will provide key data that will help understand the local region explored by Mars Surface Laboratory (MSL) as a potential habitat for life. CHAMP will also support other anticipated MSL investigations, in particular by helping identify and select the highest priority targets for sample collection and analysis by the MSL's analytical suite.
Real time non invasive imaging of fatty acid uptake in vivo
Henkin, Amy H.; Cohen, Allison S.; Dubikovskaya, Elena A.; Park, Hyo Min; Nikitin, Gennady F.; Auzias, Mathieu G.; Kazantzis, Melissa; Bertozzi, Carolyn R.; Stahl, Andreas
2012-01-01
Detection and quantification of fatty acid fluxes in animal model systems following physiological, pathological, or pharmacological challenges is key to our understanding of complex metabolic networks as these macronutrients also activate transcription factors and modulate signaling cascades including insulin-sensitivity. To enable non-invasive, real-time, spatiotemporal quantitative imaging of fatty acid fluxes in animals, we created a bioactivatable molecular imaging probe based on long-chain fatty acids conjugated to a reporter molecule (luciferin). We show that this probe faithfully recapitulates cellular fatty acid uptake and can be used in animal systems as a valuable tool to localize and quantitate in real-time lipid fluxes such as intestinal fatty acid absorption and brown adipose tissue activation. This imaging approach should further our understanding of basic metabolic processes and pathological alterations in multiple disease models. PMID:22928772
Systems Biology in Immunology – A Computational Modeling Perspective
Germain, Ronald N.; Meier-Schellersheim, Martin; Nita-Lazar, Aleksandra; Fraser, Iain D. C.
2011-01-01
Systems biology is an emerging discipline that combines high-content, multiplexed measurements with informatic and computational modeling methods to better understand biological function at various scales. Here we present a detailed review of the methods used to create computational models and conduct simulations of immune function, We provide descriptions of the key data gathering techniques employed to generate the quantitative and qualitative data required for such modeling and simulation and summarize the progress to date in applying these tools and techniques to questions of immunological interest, including infectious disease. We include comments on what insights modeling can provide that complement information obtained from the more familiar experimental discovery methods used by most investigators and why quantitative methods are needed to eventually produce a better understanding of immune system operation in health and disease. PMID:21219182
Grinstein, Amir; Kodra, Evan; Chen, Stone; Sheldon, Seth; Zik, Ory
2018-01-01
Individuals must have a quantitative understanding of the carbon footprint tied to their everyday decisions to make efficient sustainable decisions. We report research of the innumeracy of individuals as it relates to their carbon footprint. In three studies that varied in terms of scale and sample, respondents estimate the quantity of CO2 released when combusting a gallon of gasoline in comparison to several well-known metrics including food calories and travel distance. Consistently, respondents estimated the quantity of CO2 from gasoline compared to other metrics with significantly less accuracy while exhibiting a tendency to underestimate CO2. Such relative absence of carbon numeracy of even a basic consumption habit may limit the effectiveness of environmental policies and campaigns aimed at changing individual behavior. We discuss several caveats as well as opportunities for policy design that could aid the improvement of people's quantitative understanding of their carbon footprint.
Bulk magnetic domain stability controls paleointensity fidelity
NASA Astrophysics Data System (ADS)
Paterson, Greig A.; Muxworthy, Adrian R.; Yamamoto, Yuhji; Pan, Yongxin
2017-12-01
Nonideal, nonsingle-domain magnetic grains are ubiquitous in rocks; however, they can have a detrimental impact on the fidelity of paleomagnetic records—in particular the determination of ancient magnetic field strength (paleointensity), a key means of understanding the evolution of the earliest geodynamo and the formation of the solar system. As a consequence, great effort has been expended to link rock magnetic behavior to paleointensity results, but with little quantitative success. Using the most comprehensive rock magnetic and paleointensity data compilations, we quantify a stability trend in hysteresis data that characterizes the bulk domain stability (BDS) of the magnetic carriers in a paleomagnetic specimen. This trend is evident in both geological and archeological materials that are typically used to obtain paleointensity data and is therefore pervasive throughout most paleomagnetic studies. Comparing this trend to paleointensity data from both laboratory and historical experiments reveals a quantitative relationship between BDS and paleointensity behavior. Specimens that have lower BDS values display higher curvature on the paleointensity analysis plot, which leads to more inaccurate results. In-field quantification of BDS therefore reflects low-field bulk remanence stability. Rapid hysteresis measurements can be used to provide a powerful quantitative method for preselecting paleointensity specimens and postanalyzing previous studies, further improving our ability to select high-fidelity recordings of ancient magnetic fields. BDS analyses will enhance our ability to understand the evolution of the geodynamo and can help in understanding many fundamental Earth and planetary science questions that remain shrouded in controversy.
Bulk magnetic domain stability controls paleointensity fidelity
Muxworthy, Adrian R.; Yamamoto, Yuhji; Pan, Yongxin
2017-01-01
Nonideal, nonsingle-domain magnetic grains are ubiquitous in rocks; however, they can have a detrimental impact on the fidelity of paleomagnetic records—in particular the determination of ancient magnetic field strength (paleointensity), a key means of understanding the evolution of the earliest geodynamo and the formation of the solar system. As a consequence, great effort has been expended to link rock magnetic behavior to paleointensity results, but with little quantitative success. Using the most comprehensive rock magnetic and paleointensity data compilations, we quantify a stability trend in hysteresis data that characterizes the bulk domain stability (BDS) of the magnetic carriers in a paleomagnetic specimen. This trend is evident in both geological and archeological materials that are typically used to obtain paleointensity data and is therefore pervasive throughout most paleomagnetic studies. Comparing this trend to paleointensity data from both laboratory and historical experiments reveals a quantitative relationship between BDS and paleointensity behavior. Specimens that have lower BDS values display higher curvature on the paleointensity analysis plot, which leads to more inaccurate results. In-field quantification of BDS therefore reflects low-field bulk remanence stability. Rapid hysteresis measurements can be used to provide a powerful quantitative method for preselecting paleointensity specimens and postanalyzing previous studies, further improving our ability to select high-fidelity recordings of ancient magnetic fields. BDS analyses will enhance our ability to understand the evolution of the geodynamo and can help in understanding many fundamental Earth and planetary science questions that remain shrouded in controversy. PMID:29187534
NASA Astrophysics Data System (ADS)
Chen, Hui; Tan, Chao; Lin, Zan; Wu, Tong
2018-01-01
Milk is among the most popular nutrient source worldwide, which is of great interest due to its beneficial medicinal properties. The feasibility of the classification of milk powder samples with respect to their brands and the determination of protein concentration is investigated by NIR spectroscopy along with chemometrics. Two datasets were prepared for experiment. One contains 179 samples of four brands for classification and the other contains 30 samples for quantitative analysis. Principal component analysis (PCA) was used for exploratory analysis. Based on an effective model-independent variable selection method, i.e., minimal-redundancy maximal-relevance (MRMR), only 18 variables were selected to construct a partial least-square discriminant analysis (PLS-DA) model. On the test set, the PLS-DA model based on the selected variable set was compared with the full-spectrum PLS-DA model, both of which achieved 100% accuracy. In quantitative analysis, the partial least-square regression (PLSR) model constructed by the selected subset of 260 variables outperforms significantly the full-spectrum model. It seems that the combination of NIR spectroscopy, MRMR and PLS-DA or PLSR is a powerful tool for classifying different brands of milk and determining the protein content.
Betancourt, T.S.; Meyers-Ohki, S.E.; Charrow, A.; Hansen, N.
2012-01-01
Background To date, research on mental health in HIV-affected children (children who have an HIV-positive caregiver or live with the virus themselves) has focused on risk factors associated with the disease. However, simultaneous identification of factors that contribute to resilience in the face of risks is also needed. A greater understanding of modifiable protective processes that contribute to resilience in the mental health of children affected by HIV can inform the design of interventions that bolster naturally-occurring supports and contribute to early prevention or better management of risks. Methods We reviewed the recent literature on mental health and resilience in children and adolescents affected by HIV/AIDS. Literature searches of PsycInfo and PubMed were conducted during July-December 2011 consistent with Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) standards. Qualitative and quantitative studies were included for review if primary research questions pertained to mental health and coping or protective processes in children and families affected by HIV/AIDS. All studies subject to full review were evaluated for quality using a modified Systematic Assessment of Quality in Observational Research (SAQOR) rating system. Results 171 unique studies were returned from online searches of the literature and bibliography mining. Of these, 29 were evaluated as pertaining directly to mental health and resilience in families and children living with HIV/AIDS. Eight studies presented qualitative analyses. Ten quantitative studies examined individual resources contributing to child resilience and four quantitative studies looked at family-level resources. Ten studies also investigated community-level interactions. Four presented findings from resilience-focused interventions. Conclusions There is a clear need for rigorous research on mental health and resilience in HIV-affected children and adolescents. The evidence base would greatly benefit from more standardized and robust approaches to thinking about resilience from an ecological perspective inclusive of resources at multiple levels and their interactions. PMID:22943414
The chicken genome: some good news and some bad news.
Dodgson, J B
2007-07-01
The sequencing of the chicken genome has generated a wealth of good news for poultry science. It allows the chicken to be a major player in 21st century biology by providing an entrée into an arsenal of new technologies that can be used to explore virtually any chicken phenotype of interest. The initial technological onslaught has been described in this symposium. The wealth of data available now or soon to be available cannot be explained by simplistic models and will force us to treat the inherent complexity of the chicken in ways that are more realistic but at the same time more difficult to comprehend. Initial single nucleotide polymorphism analyses suggest that broilers retain a remarkable amount of the genetic diversity of predomesticated Jungle Fowl, whereas commercial layer genomes display less diversity and broader linkage disequilibrium. Thus, intensive commercial selection has not fixed a genome rich in wide selective sweeps, at least within the broiler population. Rather, a complex assortment of combinations of ancient allelic diversity survives. Low levels of linkage disequilibrium will make association analysis in broilers more difficult. The wider disequilibrium observed in layers should facilitate the mapping of quantitative trait loci, and at the same time make it more difficult to identify the causative nucleotide change(s). In addition, many quantitative traits may be specific to the genetic background in which they arose and not readily transferable to, or detectable in, other line backgrounds. Despite the obstacles it presents, the genetic complexity of the chicken may also be viewed as good news because it insures that long-term genetic progress will continue via breeding using quantitative genetics, and it surely will keep poultry scientists busy for decades to come. It is now time to move from an emphasis on obtaining "THE" chicken genome sequence to obtaining multiple sequences, especially of foundation stocks, and a broader understanding of the full genetic and phenotypic diversity of the domesticated chicken.
Gilmer, Todd P; Katz, Marian L; Stefancic, Ana; Palinkas, Lawrence A
2013-01-01
Objective. This study examined variation in the implementation of California's Full Service Partnerships (FSPs), which are supported housing programs that do “whatever it takes” to improve outcomes among persons with serious mental illness who are homeless or at risk of homelessness. Data Sources/Setting. Ninety-three FSPs in California. Study Design. A mixed methods approach was selected to develop a better understanding of the complexity of the FSP programs. The design structure was a combined explanatory and exploratory sequential design (qual→QUAN→qual) where a qualitative focus group was used to develop a quantitative survey that was followed by qualitative site visits. The survey was used to describe the breadth of variation based on fidelity to the Housing First model, while the site visits were used to provide a depth of information on high- versus low-fidelity programs. Principal Findings. We found substantial variation in implementation among FSPs. Fidelity was particularly low along domains related with housing and service philosophy, indicating that many FSPs implemented a rich array of services but applied housing readiness requirements and did not adhere to consumer choice in housing. Conclusions. There remains room for improvement in the recovery-orientation of FSPs. Fortunately, we have identified several processes by which program managers and counties can increase the fidelity of their programs. PMID:24138021
White, Marc; Wagner, Shannon; Schultz, Izabela Z; Murray, Eleanor; Bradley, Susan M; Hsu, Vernita; McGuire, Lisa; Schulz, Werner
2013-01-01
A challenge facing stakeholders is the identification and translation of relevant high quality research to inform policy and practice. This study engaged academic and community stakeholders in conducting a best evidence-synthesis to enhance knowledge use. To identify modifiable workplace disability risk and protective factors across common health conditions impacting work-related absence. We searched MEDLINE, Embase, CINHAL, The Cochrane Library, PsycINFO, BusinessSourceComplete, and ABI/Inform from 2000 to 2011. Systematic reviews that employed quantitative, qualitative, or mixed methods of work-focused population were considered for inclusion. Two or more independent reviewers reviewed titles only, titles and abstracts, and/or full articles when assessing eligibility for inclusion. Selected articles underwent methodological screening. The search strategy, expert input and grey literature identified 2,467 unique records from which 142 full text articles underwent comprehensive review. Twenty-seven systematic reviews met eligibility criteria. Modifiable work factors found to have consistent evidence across two or more health conditions included lack of social support, increased physical demands at work, job strain, lack of supervisory support, increased psychological demands, low job satisfaction, low worker control of job, and poor leadership quality. The active engagement of stakeholders led to greater understanding of relevance of the study findings for community stakeholders and appreciation of the mutual benefits of collaboration.
Full-Range Public Health Leadership, Part 2: Qualitative Analysis and Synthesis
Carlton, Erik L.; Holsinger, James W.; Riddell, Martha C.; Bush, Heather
2015-01-01
Public health leadership is an important topic in the era of U.S. health reform, population health innovation, and health system transformation. This study utilized the full-range leadership model in order to examine the public health leadership. We sought to understand local public health leadership from the perspective of local health department leaders and those who work with and for them. Public health leadership was explored through interviews and focus groups with directors (n = 4) and staff (n = 33) from local health departments. Qualitative analytic methods included reflexive journals, code-recode procedures, and member checking, with analysis facilitated by Atlas.ti v.6.0. Qualitative results supported and expanded upon previously reported quantitative findings. Leading by example and providing individual consideration to followers were found to be more important than other leader factors, such as intellectual stimulation, inspirational motivation, or idealized attributes of leaders. Having a clear and competent vision of public health, being able to work collaboratively with other community agencies, and addressing the current challenges to public health with creativity and innovation were also important findings. Idealized leadership behaviors and individual consideration should be the focus of student and professional development. Models that incorporate contextual considerations, such as the situational leadership model, could be utilized to ensure that optimal individual consideration is given to followers. PMID:26217654
Variola virus topoisomerase: DNA cleavage specificity and distribution of sites in Poxvirus genomes.
Minkah, Nana; Hwang, Young; Perry, Kay; Van Duyne, Gregory D; Hendrickson, Robert; Lefkowitz, Elliot J; Hannenhalli, Sridhar; Bushman, Frederic D
2007-08-15
Topoisomerase enzymes regulate superhelical tension in DNA resulting from transcription, replication, repair, and other molecular transactions. Poxviruses encode an unusual type IB topoisomerase that acts only at conserved DNA sequences containing the core pentanucleotide 5'-(T/C)CCTT-3'. In X-ray structures of the variola virus topoisomerase bound to DNA, protein-DNA contacts were found to extend beyond the core pentanucleotide, indicating that the full recognition site has not yet been fully defined in functional studies. Here we report quantitation of DNA cleavage rates for an optimized 13 bp site and for all possible single base substitutions (40 total sites), with the goals of understanding the molecular mechanism of recognition and mapping topoisomerase sites in poxvirus genome sequences. The data allow a precise definition of enzyme-DNA interactions and the energetic contributions of each. We then used the resulting "action matrix" to show that favorable topoisomerase sites are distributed all along the length of poxvirus DNA sequences, consistent with a requirement for local release of superhelical tension in constrained topological domains. In orthopox genomes, an additional central cluster of sites was also evident. A negative correlation of predicted topoisomerase sites was seen relative to early terminators, but no correlation was seen with early or late promoters. These data define the full variola virus topoisomerase recognition site and provide a new window on topoisomerase function in vivo.
Knowles, David W; Biggin, Mark D
2013-01-01
Animals comprise dynamic three-dimensional arrays of cells that express gene products in intricate spatial and temporal patterns that determine cellular differentiation and morphogenesis. A rigorous understanding of these developmental processes requires automated methods that quantitatively record and analyze complex morphologies and their associated patterns of gene expression at cellular resolution. Here we summarize light microscopy-based approaches to establish permanent, quantitative datasets-atlases-that record this information. We focus on experiments that capture data for whole embryos or large areas of tissue in three dimensions, often at multiple time points. We compare and contrast the advantages and limitations of different methods and highlight some of the discoveries made. We emphasize the need for interdisciplinary collaborations and integrated experimental pipelines that link sample preparation, image acquisition, image analysis, database design, visualization, and quantitative analysis. Copyright © 2013 Wiley Periodicals, Inc.
Genetic interactions contribute less than additive effects to quantitative trait variation in yeast
Bloom, Joshua S.; Kotenko, Iulia; Sadhu, Meru J.; Treusch, Sebastian; Albert, Frank W.; Kruglyak, Leonid
2015-01-01
Genetic mapping studies of quantitative traits typically focus on detecting loci that contribute additively to trait variation. Genetic interactions are often proposed as a contributing factor to trait variation, but the relative contribution of interactions to trait variation is a subject of debate. Here we use a very large cross between two yeast strains to accurately estimate the fraction of phenotypic variance due to pairwise QTL–QTL interactions for 20 quantitative traits. We find that this fraction is 9% on average, substantially less than the contribution of additive QTL (43%). Statistically significant QTL–QTL pairs typically have small individual effect sizes, but collectively explain 40% of the pairwise interaction variance. We show that pairwise interaction variance is largely explained by pairs of loci at least one of which has a significant additive effect. These results refine our understanding of the genetic architecture of quantitative traits and help guide future mapping studies. PMID:26537231
Choi, Seo Yeon; Yang, Nuri; Jeon, Soo Kyung; Yoon, Tae Hyun
2014-09-01
In this study, we have demonstrated feasibility of a semi-quantitative approach for the estimation of cellular SiO2 nanoparticles (NPs), which is based on the flow cytometry measurements of their normalized side scattering intensity. In order to improve our understanding on the quantitative aspects of cell-nanoparticle interactions, flow cytometry, transmission electron microscopy, and X-ray fluorescence experiments were carefully performed for the HeLa cells exposed to SiO2 NPs with different core diameters, hydrodynamic sizes, and surface charges. Based on the observed relationships among the experimental data, a semi-quantitative cellular SiO2 NPs estimation method from their normalized side scattering and core diameters was proposed, which can be applied for the determination of cellular SiO2 NPs within their size-dependent linear ranges. © 2014 International Society for Advancement of Cytometry.
Analyzing 7000 texts on deep brain stimulation: what do they tell us?
Ineichen, Christian; Christen, Markus
2015-01-01
The enormous increase in numbers of scientific publications in the last decades requires quantitative methods for obtaining a better understanding of topics and developments in various fields. In this exploratory study, we investigate the emergence, trends, and connections of topics within the whole text corpus of the deep brain stimulation (DBS) literature based on more than 7000 papers (title and abstracts) published between 1991 to 2014 using a network approach. Taking the co-occurrence of basic terms that represent important topics within DBS as starting point, we outline the statistics of interconnections between DBS indications, anatomical targets, positive, and negative effects, as well as methodological, technological, and economic issues. This quantitative approach confirms known trends within the literature (e.g., regarding the emergence of psychiatric indications). The data also reflect an increased discussion about complex issues such as personality connected tightly to the ethical context, as well as an apparent focus on depression as important DBS indication, where the co-occurrence of terms related to negative effects is low both for the indication as well as the related anatomical targets. We also discuss consequences of the analysis from a bioethical perspective, i.e., how such a quantitative analysis could uncover hidden subject matters that have ethical relevance. For example, we find that hardware-related issues in DBS are far more robustly connected to an ethical context compared to impulsivity, concrete side-effects or death/suicide. Our contribution also outlines the methodology of quantitative text analysis that combines statistical approaches with expert knowledge. It thus serves as an example how innovative quantitative tools can be made useful for gaining a better understanding in the field of DBS.
Analyzing 7000 texts on deep brain stimulation: what do they tell us?
Ineichen, Christian; Christen, Markus
2015-01-01
The enormous increase in numbers of scientific publications in the last decades requires quantitative methods for obtaining a better understanding of topics and developments in various fields. In this exploratory study, we investigate the emergence, trends, and connections of topics within the whole text corpus of the deep brain stimulation (DBS) literature based on more than 7000 papers (title and abstracts) published between 1991 to 2014 using a network approach. Taking the co-occurrence of basic terms that represent important topics within DBS as starting point, we outline the statistics of interconnections between DBS indications, anatomical targets, positive, and negative effects, as well as methodological, technological, and economic issues. This quantitative approach confirms known trends within the literature (e.g., regarding the emergence of psychiatric indications). The data also reflect an increased discussion about complex issues such as personality connected tightly to the ethical context, as well as an apparent focus on depression as important DBS indication, where the co-occurrence of terms related to negative effects is low both for the indication as well as the related anatomical targets. We also discuss consequences of the analysis from a bioethical perspective, i.e., how such a quantitative analysis could uncover hidden subject matters that have ethical relevance. For example, we find that hardware-related issues in DBS are far more robustly connected to an ethical context compared to impulsivity, concrete side-effects or death/suicide. Our contribution also outlines the methodology of quantitative text analysis that combines statistical approaches with expert knowledge. It thus serves as an example how innovative quantitative tools can be made useful for gaining a better understanding in the field of DBS. PMID:26578908
Fuochi, G; Foà, C
2018-03-01
Quality of life, coping strategies, social support and self-efficacy are important psychosocial variables strongly affecting the experience of acute myocardial infarction (AMI) in women. To gain a more in-depth understanding of how coping strategies, self-efficacy, quality of life and social support shape women's adjustment to AMI. Mixed methods study. Quantitative data were collected through a standardised questionnaire on coping strategies, self-efficacy, quality of life and social support. Qualitative data stemmed from 57 semistructured interviews conducted with post-AMI female patients on related topics. Quantitative data were analysed with unpaired two-sample t-tests on the means, comparing women who experienced AMI (N = 77) with a control group of women who did not have AMI (N = 173), and pairwise correlations on the AMI sample. Qualitative data were grouped into coding families and analysed through thematic content analysis. Qualitative and quantitative results were then integrated, for different age groups. Quantitative results indicated statistically significant differences between women who experienced AMI and the control group: the former showed lower self-perceived health, perceived social support and social support coping, but greater self-efficacy, use of acceptance, avoidance and religious coping. Pairwise correlations showed that avoidance coping strategy was negatively correlated with quality of life, while the opposite was true for problem-oriented coping, perceived social support and self-efficacy. Qualitative results extended and confirmed quantitative results, except for coping strategies: avoidance coping seemed more present than reported in the standardised measures. Mixed methods provide understanding of the importance of social support, self-efficacy and less avoidant coping strategies to women's adjustment to AMI. Women need support from health professionals with knowledge of these topics, to facilitate their adaptation to AMI. © 2017 Nordic College of Caring Science.
Fostering a Sense of Wonder in the Science Classroom
NASA Astrophysics Data System (ADS)
Hadzigeorgiou, Yannis Petros
2012-10-01
This paper reports on a study undertaken with the primary aim of investigating the role of wonder in the learning process. The study was carried out by a 9th grade science teacher in collaboration with a university professor. The teacher taught two classrooms of 27 and 30 students respectively, by trying to evoke a sense of wonder only in one of them. To this end the teacher identified ideas and phenomena as potential sources of wonder and initiated the instruction through these ideas and phenomena. Observation and especially student optional journals were the main instruments of the research. A quantitative analysis of journal entries made by the students of both classrooms, provided evidence for higher involvement for the students—both males and females—of the classroom where the teacher evoked a sense of wonder. Also an analysis of students' comments provided evidence that wonder, experienced as astonishment and a shock of awareness can help students change their outlook on natural phenomena. Moreover two paper-and-pencil tests administered at the end of the school year provided additional evidence that wonder had an effect on students' ability to remember "wonder-full" ideas and also an effect on better understanding, of at least, three phenomena. This empirical evidence of better retention and understanding is evidence of the role of wonder as an attention catcher and generally of the role of affective factors in the learning process.
A systematic review of perceived barriers and motivators to physical activity after stroke.
Nicholson, Sarah; Sniehotta, Falko F; van Wijck, Frederike; Greig, Carolyn A; Johnston, Marie; McMurdo, Marion E T; Dennis, Martin; Mead, Gillian E
2013-07-01
Physical fitness is impaired after stroke, may contribute to disability, yet is amenable to improvement through regular physical activity. To facilitate uptake and maintenance of physical activity, it is essential to understand stroke survivors' perceived barriers and motivators. Therefore, we undertook a systematic review of perceived barriers and motivators to physical activity after stroke. Electronic searches of EMBASE, Medline, CINAHL, and PsychInfo were performed. We included peer-reviewed journal articles, in English, between 1 January 1966 and 30 August 2010 reporting stroke survivors' perceived barriers and motivators to physical activity. Searches identified 73,807 citations of which 57 full articles were retrieved. Six articles were included, providing data on 174 stroke survivors (range 10 to 83 per article). Two reported barriers and motivators, two reported only motivators, and two reported only barriers. Five were qualitative articles and one was quantitative. The most commonly reported barriers were lack of motivation, environmental factors (e.g. transport), health concerns, and stroke impairments. The most commonly reported motivators were social support and the need to be able to perform daily tasks. This review has furthered our understanding of the perceived barriers and motivators to physical activity after a stroke. This review will enable the development of tailored interventions to target barriers, while building upon perceived motivators to increase and maintain stroke survivors' physical activity. © 2012 The Authors. International Journal of Stroke © 2012 World Stroke Organization.
Qiao, Guang; Wen, Xiao-Peng; Zhang, Ting
2015-12-01
Light-harvesting chlorophyll a/b-binding proteins (LHCB) have been implicated in the stress response. In this study, a gene encoding LHCB in the pigeon pea was cloned and characterized. Based on the sequence of a previously obtained 327 bp Est, a full-length 793 bp cDNA was cloned using the rapid amplification of cDNA ends (RACE) method. It was designated CcLHCB1 and encoded a 262 amino acid protein. The calculated molecular weight of the CcLHCB1 protein was 27.89 kDa, and the theoretical isoelectric point was 5.29. Homology search and sequence multi-alignment demonstrated that the CcLHCB1 protein sequence shared a high identity with LHCB from other plants. Bioinformatics analysis revealed that CcLHCB1 was a hydrophobic protein with three transmembrane domains. By fluorescent quantitative real-time polymerase chain reaction (PCR), CcLHCB1 mRNA transcripts were detectable in different tissues (leaf, stem, and root), with the highest level found in the leaf. The expression of CcLHCB1 mRNA in the leaves was up-regulated by drought stimulation and AM inoculation. Our results provide the basis for a better understanding of the molecular organization of LCHB and might be useful for understanding the interaction between plants and microbes in the future.
West, Aaron C; Duchimaza-Heredia, Juan J; Gordon, Mark S; Ruedenberg, Klaus
2017-11-22
The quasi-atomic analysis of ab initio electronic wave functions in full valence spaces, which was developed in preceding papers, yields oriented quasi-atomic orbitals in terms of which the ab initio molecular wave function and energy can be expressed. These oriented quasi-atomic orbitals are the rigorous ab initio counterparts to the conceptual bond forming atomic hybrid orbitals of qualitative chemical reasoning. In the present work, the quasi-atomic orbitals are identified as bonding orbitals, lone pair orbitals, radical orbitals, vacant orbitals and orbitals with intermediate character. A program determines the bonding characteristics of all quasi-atomic orbitals in a molecule on the basis of their occupations, bond orders, kinetic bond orders, hybridizations and local symmetries. These data are collected in a record and provide the information for a comprehensive understanding of the synergism that generates the bonding structure that holds the molecule together. Applications to a series of molecules exhibit the complete bonding structures that are embedded in their ab initio wave functions. For the strong bonds in a molecule, the quasi-atomic orbitals provide quantitative ab initio amplifications of the Lewis dot symbols. Beyond characterizing strong bonds, the quasi-atomic analysis also yields an understanding of the weak interactions, such as vicinal, hyperconjugative and radical stabilizations, which can make substantial contributions to the molecular bonding structure.
NASA Astrophysics Data System (ADS)
Guan, Mingfu; Ahilan, Sangaralingam; Yu, Dapeng; Peng, Yong; Wright, Nigel
2018-01-01
Fine sediment plays crucial and multiple roles in the hydrological, ecological and geomorphological functioning of river systems. This study employs a two-dimensional (2D) numerical model to track the hydro-morphological processes dominated by fine suspended sediment, including the prediction of sediment concentration in flow bodies, and erosion and deposition caused by sediment transport. The model is governed by 2D full shallow water equations with which an advection-diffusion equation for fine sediment is coupled. Bed erosion and sedimentation are updated by a bed deformation model based on local sediment entrainment and settling flux in flow bodies. The model is initially validated with the three laboratory-scale experimental events where suspended load plays a dominant role. Satisfactory simulation results confirm the model's capability in capturing hydro-morphodynamic processes dominated by fine suspended sediment at laboratory-scale. Applications to sedimentation in a stormwater pond are conducted to develop the process-based understanding of fine sediment dynamics over a variety of flow conditions. Urban flows with 5-year, 30-year and 100-year return period and the extreme flood event in 2012 are simulated. The modelled results deliver a step change in understanding fine sediment dynamics in stormwater ponds. The model is capable of quantitatively simulating and qualitatively assessing the performance of a stormwater pond in managing urban water quantity and quality.
Li, Jun; Jiang, Bin; Song, Hongwei; ...
2015-04-17
Here, we survey the recent advances in theoretical understanding of quantum state resolved dynamics, using the title reactions as examples. It is shown that the progress was made possible by major developments in two areas. First, an accurate analytical representation of many high-level ab initio points over a large configuration space can now be made with high fidelity and the necessary permutation symmetry. The resulting full-dimensional global potential energy surfaces enable dynamical calculations using either quasi-classical trajectory or more importantly quantum mechanical methods. The second advance is the development of accurate and efficient quantum dynamical methods, which are necessary formore » providing a reliable treatment of quantum effects in reaction dynamics such as tunneling, resonances, and zero-point energy. The powerful combination of the two advances has allowed us to achieve a quantitatively accurate characterization of the reaction dynamics, which unveiled rich dynamical features such as steric steering, strong mode specificity, and bond selectivity. The dependence of reactivity on reactant modes can be rationalized by the recently proposed sudden vector projection model, which attributes the mode specificity and bond selectivity to the coupling of reactant modes with the reaction coordinate at the relevant transition state. The deeper insights provided by these theoretical studies have advanced our understanding of reaction dynamics to a new level.« less
NASA Astrophysics Data System (ADS)
Muenich, R. L.; Kalcic, M. M.; Teshager, A. D.; Long, C. M.; Wang, Y. C.; Scavia, D.
2017-12-01
Thanks to the availability of open-source software, online tutorials, and advanced software capabilities, watershed modeling has expanded its user-base and applications significantly in the past thirty years. Even complicated models like the Soil and Water Assessment Tool (SWAT) are being used and documented in hundreds of peer-reviewed publications each year, and likely more applied in practice. These models can help improve our understanding of present, past, and future conditions, or analyze important "what-if" management scenarios. However, baseline data and methods are often adopted and applied without rigorous testing. In multiple collaborative projects, we have evaluated the influence of some of these common approaches on model results. Specifically, we examined impacts of baseline data and assumptions involved in manure application, combined sewer overflows, and climate data incorporation across multiple watersheds in the Western Lake Erie Basin. In these efforts, we seek to understand the impact of using typical modeling data and assumptions, versus using improved data and enhanced assumptions on model outcomes and thus ultimately, study conclusions. We provide guidance for modelers as they adopt and apply data and models for their specific study region. While it is difficult to quantitatively assess the full uncertainty surrounding model input data and assumptions, recognizing the impacts of model input choices is important when considering actions at the both the field and watershed scales.
Hansen, Matthew; O’Brien, Kerth; Meckler, Garth; Chang, Anna Marie; Guise, Jeanne-Marie
2016-01-01
Mixed methods research has significant potential to broaden the scope of emergency care and specifically emergency medical services investigation. Mixed methods studies involve the coordinated use of qualitative and quantitative research approaches to gain a fuller understanding of practice. By combining what is learnt from multiple methods, these approaches can help to characterise complex healthcare systems, identify the mechanisms of complex problems such as medical errors and understand aspects of human interaction such as communication, behaviour and team performance. Mixed methods approaches may be particularly useful for out-of-hospital care researchers because care is provided in complex systems where equipment, interpersonal interactions, societal norms, environment and other factors influence patient outcomes. The overall objectives of this paper are to (1) introduce the fundamental concepts and approaches of mixed methods research and (2) describe the interrelation and complementary features of the quantitative and qualitative components of mixed methods studies using specific examples from the Children’s Safety Initiative-Emergency Medical Services (CSI-EMS), a large National Institutes of Health-funded research project conducted in the USA. PMID:26949970
Quantitative analysis on electrooculography (EOG) for neurodegenerative disease
NASA Astrophysics Data System (ADS)
Liu, Chang-Chia; Chaovalitwongse, W. Art; Pardalos, Panos M.; Seref, Onur; Xanthopoulos, Petros; Sackellares, J. C.; Skidmore, Frank M.
2007-11-01
Many studies have documented abnormal horizontal and vertical eye movements in human neurodegenerative disease as well as during altered states of consciousness (including drowsiness and intoxication) in healthy adults. Eye movement measurement may play an important role measuring the progress of neurodegenerative diseases and state of alertness in healthy individuals. There are several techniques for measuring eye movement, Infrared detection technique (IR). Video-oculography (VOG), Scleral eye coil and EOG. Among those available recording techniques, EOG is a major source for monitoring the abnormal eye movement. In this real-time quantitative analysis study, the methods which can capture the characteristic of the eye movement were proposed to accurately categorize the state of neurodegenerative subjects. The EOG recordings were taken while 5 tested subjects were watching a short (>120 s) animation clip. In response to the animated clip the participants executed a number of eye movements, including vertical smooth pursued (SVP), horizontal smooth pursued (HVP) and random saccades (RS). Detection of abnormalities in ocular movement may improve our diagnosis and understanding a neurodegenerative disease and altered states of consciousness. A standard real-time quantitative analysis will improve detection and provide a better understanding of pathology in these disorders.
Identifying the genes underlying quantitative traits: a rationale for the QTN programme.
Lee, Young Wha; Gould, Billie A; Stinchcombe, John R
2014-01-01
The goal of identifying the genes or even nucleotides underlying quantitative and adaptive traits has been characterized as the 'QTN programme' and has recently come under severe criticism. Part of the reason for this criticism is that much of the QTN programme has asserted that finding the genes and nucleotides for adaptive and quantitative traits is a fundamental goal, without explaining why it is such a hallowed goal. Here we outline motivations for the QTN programme that offer general insight, regardless of whether QTNs are of large or small effect, and that aid our understanding of the mechanistic dynamics of adaptive evolution. We focus on five areas: (i) vertical integration of insight across different levels of biological organization, (ii) genetic parallelism and the role of pleiotropy in shaping evolutionary dynamics, (iii) understanding the forces maintaining genetic variation in populations, (iv) distinguishing between adaptation from standing variation and new mutation, and (v) the role of genomic architecture in facilitating adaptation. We argue that rather than abandoning the QTN programme, we should refocus our efforts on topics where molecular data will be the most effective for testing hypotheses about phenotypic evolution.
Identifying the genes underlying quantitative traits: a rationale for the QTN programme
Lee, Young Wha; Gould, Billie A.; Stinchcombe, John R.
2014-01-01
The goal of identifying the genes or even nucleotides underlying quantitative and adaptive traits has been characterized as the ‘QTN programme’ and has recently come under severe criticism. Part of the reason for this criticism is that much of the QTN programme has asserted that finding the genes and nucleotides for adaptive and quantitative traits is a fundamental goal, without explaining why it is such a hallowed goal. Here we outline motivations for the QTN programme that offer general insight, regardless of whether QTNs are of large or small effect, and that aid our understanding of the mechanistic dynamics of adaptive evolution. We focus on five areas: (i) vertical integration of insight across different levels of biological organization, (ii) genetic parallelism and the role of pleiotropy in shaping evolutionary dynamics, (iii) understanding the forces maintaining genetic variation in populations, (iv) distinguishing between adaptation from standing variation and new mutation, and (v) the role of genomic architecture in facilitating adaptation. We argue that rather than abandoning the QTN programme, we should refocus our efforts on topics where molecular data will be the most effective for testing hypotheses about phenotypic evolution. PMID:24790125
Systems microscopy: an emerging strategy for the life sciences.
Lock, John G; Strömblad, Staffan
2010-05-01
Dynamic cellular processes occurring in time and space are fundamental to all physiology and disease. To understand complex and dynamic cellular processes therefore demands the capacity to record and integrate quantitative multiparametric data from the four spatiotemporal dimensions within which living cells self-organize, and to subsequently use these data for the mathematical modeling of cellular systems. To this end, a raft of complementary developments in automated fluorescence microscopy, cell microarray platforms, quantitative image analysis and data mining, combined with multivariate statistics and computational modeling, now coalesce to produce a new research strategy, "systems microscopy", which facilitates systems biology analyses of living cells. Systems microscopy provides the crucial capacities to simultaneously extract and interrogate multiparametric quantitative data at resolution levels ranging from the molecular to the cellular, thereby elucidating a more comprehensive and richly integrated understanding of complex and dynamic cellular systems. The unique capacities of systems microscopy suggest that it will become a vital cornerstone of systems biology, and here we describe the current status and future prospects of this emerging field, as well as outlining some of the key challenges that remain to be overcome. Copyright 2010 Elsevier Inc. All rights reserved.
Quantitative confirmation of diffusion-limited oxidation theories
DOE Office of Scientific and Technical Information (OSTI.GOV)
Gillen, K.T.; Clough, R.L.
1990-01-01
Diffusion-limited (heterogeneous) oxidation effects are often important for studies of polymer degradation. Such effects are common in polymers subjected to ionizing radiation at relatively high dose rate. To better understand the underlying oxidation processes and to aid in the planning of accelerated aging studies, it would be desirable to be able to monitor and quantitatively understand these effects. In this paper, we briefly review a theoretical diffusion approach which derives model profiles for oxygen surrounded sheets of material by combining oxygen permeation rates with kinetically based oxygen consumption expressions. The theory leads to a simple governing expression involving the oxygenmore » consumption and permeation rates together with two model parameters {alpha} and {beta}. To test the theory, gamma-initiated oxidation of a sheet of commercially formulated EPDM rubber was performed under conditions which led to diffusion-limited oxidation. Profile shapes from the theoretical treatments are shown to accurately fit experimentally derived oxidation profiles. In addition, direct measurements on the same EPDM material of the oxygen consumption and permeation rates, together with values of {alpha} and {beta} derived from the fitting procedure, allow us to quantitatively confirm for the first time the governing theoretical relationship. 17 refs., 3 figs.« less
Leal, Cristiano; Amaral, António Luís; Costa, Maria de Lourdes
2016-08-01
Activated sludge systems are prone to be affected by foaming occurrences causing the sludge to rise in the reactor and affecting the wastewater treatment plant (WWTP) performance. Nonetheless, there is currently a knowledge gap hindering the development of foaming events prediction tools that may be fulfilled by the quantitative monitoring of AS systems biota and sludge characteristics. As such, the present study focuses on the assessment of foaming events in full-scale WWTPs, by quantitative protozoa, metazoa, filamentous bacteria, and sludge characteristics analysis, further used to enlighten the inner relationships between these parameters. In the current study, a conventional activated sludge system (CAS) and an oxidation ditch (OD) were surveyed throughout a period of 2 and 3 months, respectively, regarding their biota and sludge characteristics. The biota community was monitored by microscopic observation, and a new filamentous bacteria index was developed to quantify their occurrence. Sludge characteristics (aggregated and filamentous biomass contents and aggregate size) were determined by quantitative image analysis (QIA). The obtained data was then processed by principal components analysis (PCA), cross-correlation analysis, and decision trees to assess the foaming occurrences, and enlighten the inner relationships. It was found that such events were best assessed by the combined use of the relative abundance of testate amoeba and nocardioform filamentous index, presenting a 92.9 % success rate for overall foaming events, and 87.5 and 100 %, respectively, for persistent and mild events.
ALA-induced PpIX spectroscopy for brain tumor image-guided surgery
NASA Astrophysics Data System (ADS)
Valdes, Pablo A.; Leblond, Frederic; Kim, Anthony; Harris, Brent T.; Wilson, Brian C.; Paulsen, Keith D.; Roberts, David W.
2011-03-01
Maximizing the extent of brain tumor resection correlates with improved survival and quality of life outcomes in patients. Optimal surgical resection requires accurate discrimination between normal and abnormal, cancerous tissue. We present our recent experience using quantitative optical spectroscopy in 5-aminolevulinic acid (ALA)-induced protoporphyrin IX (PpIX) fluorescence-guided resection. Exogenous administration of ALA leads to preferential accumulation in tumor tissue of the fluorescent compound, PpIX, which can be used for in vivo surgical guidance. Using the state of the art approach with a fluorescence surgical microscope, we have been able to visualize a subset of brain tumors, but the sensitivity and accuracy of fluorescence detection for tumor tissue with this system are low. To take full advantage of the biological selectivity of PpIX accumulation in brain tumors, we used a quantitative optical spectroscopy system for in vivo measurements of PpIX tissue concentrations. We have shown that, using our quantitative approach for determination of biomarker concentrations, ALA-induced PpIX fluorescence-guidance can achieve accuracies of greater than 90% for most tumor histologies. Here we show multivariate analysis of fluorescence and diffuse reflectance signals in brain tumors with comparable diagnostic performance to our previously reported quantitative approach. These results are promising, since they show that technological improvements in current fluorescence-guided surgical technologies and more biologically relevant approaches are required to take full advantage of fluorescent biomarkers, achieve better tumor identification, increase extent of resection, and subsequently, lead to improve survival and quality of life in patients.
(EGS) Geothermal resource assessment High pressure, high temperature reaction systems Research Interests EGS demonstration and deployment Advanced drilling systems research Thermodynamics and process Phenomenological Experimental Demonstrations to Quantitative Understanding." Journal of Supercritical Fluids
EDITORIAL: SPECTROSCOPIC IMAGING
A foremost goal in biology is understanding the molecular basis of single cell behavior, as well as cell interactions that result in functioning tissues. Accomplishing this goal requires quantitative analysis of multiple, specific macromolecules (e.g. proteins, ligands and enzyme...
Nuclear physics: Close encounters of the alpha kind
Quaglioni, Sofia
2015-12-02
Here, breakthrough calculations of collisions between two helium nuclei pave the way to a quantitative understanding of how the elements carbon and oxygen were made in stars — and to improved models of stellar evolution.
Qualitative versus quantitative methods in psychiatric research.
Razafsha, Mahdi; Behforuzi, Hura; Azari, Hassan; Zhang, Zhiqun; Wang, Kevin K; Kobeissy, Firas H; Gold, Mark S
2012-01-01
Qualitative studies are gaining their credibility after a period of being misinterpreted as "not being quantitative." Qualitative method is a broad umbrella term for research methodologies that describe and explain individuals' experiences, behaviors, interactions, and social contexts. In-depth interview, focus groups, and participant observation are among the qualitative methods of inquiry commonly used in psychiatry. Researchers measure the frequency of occurring events using quantitative methods; however, qualitative methods provide a broader understanding and a more thorough reasoning behind the event. Hence, it is considered to be of special importance in psychiatry. Besides hypothesis generation in earlier phases of the research, qualitative methods can be employed in questionnaire design, diagnostic criteria establishment, feasibility studies, as well as studies of attitude and beliefs. Animal models are another area that qualitative methods can be employed, especially when naturalistic observation of animal behavior is important. However, since qualitative results can be researcher's own view, they need to be statistically confirmed, quantitative methods. The tendency to combine both qualitative and quantitative methods as complementary methods has emerged over recent years. By applying both methods of research, scientists can take advantage of interpretative characteristics of qualitative methods as well as experimental dimensions of quantitative methods.
Algorithm-enabled partial-angular-scan configurations for dual-energy CT.
Chen, Buxin; Zhang, Zheng; Xia, Dan; Sidky, Emil Y; Pan, Xiaochuan
2018-05-01
We seek to investigate an optimization-based one-step method for image reconstruction that explicitly compensates for nonlinear spectral response (i.e., the beam-hardening effect) in dual-energy CT, to investigate the feasibility of the one-step method for enabling two dual-energy partial-angular-scan configurations, referred to as the short- and half-scan configurations, on standard CT scanners without involving additional hardware, and to investigate the potential of the short- and half-scan configurations in reducing imaging dose and scan time in a single-kVp-switch full-scan configuration in which two full rotations are made for collection of dual-energy data. We use the one-step method to reconstruct images directly from dual-energy data through solving a nonconvex optimization program that specifies the images to be reconstructed in dual-energy CT. Dual-energy full-scan data are generated from numerical phantoms and collected from physical phantoms with the standard single-kVp-switch full-scan configuration, whereas dual-energy short- and half-scan data are extracted from the corresponding full-scan data. Besides visual inspection and profile-plot comparison, the reconstructed images are analyzed also in quantitative studies based upon tasks of linear-attenuation-coefficient and material-concentration estimation and of material differentiation. Following the performance of a computer-simulation study to verify that the one-step method can reconstruct numerically accurately basis and monochromatic images of numerical phantoms, we reconstruct basis and monochromatic images by using the one-step method from real data of physical phantoms collected with the full-, short-, and half-scan configurations. Subjective inspection based upon visualization and profile-plot comparison reveals that monochromatic images, which are used often in practical applications, reconstructed from the full-, short-, and half-scan data are largely visually comparable except for some differences in texture details. Moreover, quantitative studies based upon tasks of linear-attenuation-coefficient and material-concentration estimation and of material differentiation indicate that the short- and half-scan configurations yield results in close agreement with the ground-truth information and that of the full-scan configuration. The one-step method considered can compensate effectively for the nonlinear spectral response in full- and partial-angular-scan dual-energy CT. It can be exploited for enabling partial-angular-scan configurations on standard CT scanner without involving additional hardware. Visual inspection and quantitative studies reveal that, with the one-step method, partial-angular-scan configurations considered can perform at a level comparable to that of the full-scan configuration, thus suggesting the potential of the two partial-angular-scan configurations in reducing imaging dose and scan time in the standard single-kVp-switch full-scan CT in which two full rotations are performed. The work also yields insights into the investigation and design of other nonstandard scan configurations of potential practical significance in dual-energy CT. © 2018 American Association of Physicists in Medicine.
Developing a global model of magnetospheric substorms
NASA Astrophysics Data System (ADS)
Kan, J. R.
1990-09-01
Competing models of magnetospheric substorms are discussed. The definitions of the three substorm phases are presented, and the advantages and drawbacks of the near-earth X-line model, magnetosphere-ionosphere coupling model, low-latitude boundary layer model, and thermal catastrophe model are examined. It is shown that the main challenge to achieving a quantitative understanding of the magnetospheric signatures of substorms is to understand the anomalous dissipation processes in collisionless plasmas.
ERIC Educational Resources Information Center
Walahoski, Jill
2013-01-01
This mixed methods case study was designed to assess the preparedness of former Nebraska 4-H participants to successfully transition and adjust to college. The study also sought to understand the way that students' experiences in Nebraska 4-H may have influenced their readiness to transition to college. The initial quantitative stage of this case…
Radio Studies of Coronal Holes.
1981-03-01
Withbroe (1978) has pointed out, "The transport of energy by thermal conduction into the transition zone is a primary coronal cooling mechanism." Thus, the...temperature and particle density gradients in the transition zone are of critical importance in understanding the energy balance of a coronal hole. The...coronal hole has been provided by Konp and Orrall (1977), but a quantitative understanding requires a detailed knowledge of the energy balance in the
ERIC Educational Resources Information Center
Hermoso, Katrina Virata
2013-01-01
The unique experiences of community college transfer students have not been explored at public, four-year universities. Most of the research on the experiences of community college students is based on quantitative research methods, which fail to provide a comprehensive understanding of the nature of students' lived experiences. This qualitative…
Squitieri, Lee; Larson, Bradley P.; Chang, Kate W-C.; Yang, Lynda J-S.; Chung, Kevin C.
2014-01-01
Purpose Quality of life (QOL) among adolescents with neonatal brachial plexus palsy (NBPP) is an important but unexplored topic. To date, few NBPP studies use comprehensive patient-reported outcome measures, and none specifically address the adolescent population. This study explores the long-term QOL and patient expectations among adolescents with NBPP using qualitative and quantitative approaches. Methods Eighteen adolescents with residual NBPP impairment between the ages of 10 to 17 years along with their parents were included in our study. Adolescents and their parents underwent separate one hour tape-recorded semi-structured interviews, which were audio recorded and transcribed. We also collected quantitative patient outcome measures to quantify the degree of each adolescent’s functional impairment and to increase our understanding of long-term quality of life and patient expectations. Results Thirteen females and five males with a mean age of 11.6 years participated in our study. Through qualitative analysis we identified the following factors contributing to overall QOL from the patient and parent perspective: social impact and peer acceptance, emotional adjustment, aesthetic concerns and body image, functional limitations, physical and occupational therapy, finances, pain, and family dynamics. Despite residual impairment, most adolescents and their parents reported a good overall QOL according to quantitative outcome measures, with adolescents reporting slightly higher QOL than their parents. However, both adolescents and their parents report relatively modest satisfaction with their current condition and express expectations for improvement in multiple areas. Discussion Understanding patient expectations and QOL in NBPP adolescents are essential for medical decision-making and advancing care. Our study results showed that functional and aesthetic factors were responsible for the majority of observed differences in QOL among NBPP adolescents. We also found that the PODCI might be more sensitive than the CHQ in assessing patient expectations and quality of life among this patient population. PMID:24416766
Skovgaard, Thomas; Bredahl, Thomas
2018-01-01
Introduction The benefits of physical activity for children’s health, both mental and physical, and its positive effects on academic achievement are well established. Research also emphasises that schools could provide a natural setting for regular physical activity. There is, however, a limited amount of knowledge about teachers’ views when it comes to integrating physical activity as part of teaching. The aim of this study is to understand teachers’ motivation for integrating physical activity as part of teaching and to assess their need for guidance and support. Methods and analysis The study uses an explanatory sequential mixed-methods design. Schools from across Denmark are included in the sample. The design comprises two separated phases—a quantitative and qualitative phase. The quantitative phase is guided by the self-determination theory where teachers’ motivation will be measured using the Work Task Motivation Scale for Teachers. The theory of scaffolding guides the qualitative phase, which consists of in-depth interviews with participants selected from the quantitative phase based on levels of motivation and on demographic information. In accordance with the study aims, the analysis of data will identify teachers’ internal and external levels of motivation. The purpose of the qualitative phase is to enhance understanding of teachers’ motivation and of their need for support in the use of physical activity in teaching. Ethics and dissemination All relevant ethics approvals have been acquired. All participants in this study will provide written informed consent prior to data collection. All data emerging from the quantitative and qualitative phase will be anonymised for analysis. Ethics approval was requested from the Regional Committee on Health Research Ethics for Southern Denmark approval ID S-20162000–40 and the Danish Data Protection Agency approval ID 16/15491). The study was deemed not notifiable by both authorities. Trial registration number NCT02894346; Pre-results. PMID:29540419
Knudsen, Louise Stjerne; Skovgaard, Thomas; Bredahl, Thomas
2018-03-14
The benefits of physical activity for children's health, both mental and physical, and its positive effects on academic achievement are well established. Research also emphasises that schools could provide a natural setting for regular physical activity. There is, however, a limited amount of knowledge about teachers' views when it comes to integrating physical activity as part of teaching. The aim of this study is to understand teachers' motivation for integrating physical activity as part of teaching and to assess their need for guidance and support. The study uses an explanatory sequential mixed-methods design. Schools from across Denmark are included in the sample. The design comprises two separated phases-a quantitative and qualitative phase. The quantitative phase is guided by the self-determination theory where teachers' motivation will be measured using the Work Task Motivation Scale for Teachers. The theory of scaffolding guides the qualitative phase, which consists of in-depth interviews with participants selected from the quantitative phase based on levels of motivation and on demographic information. In accordance with the study aims, the analysis of data will identify teachers' internal and external levels of motivation. The purpose of the qualitative phase is to enhance understanding of teachers' motivation and of their need for support in the use of physical activity in teaching. All relevant ethics approvals have been acquired. All participants in this study will provide written informed consent prior to data collection. All data emerging from the quantitative and qualitative phase will be anonymised for analysis. Ethics approval was requested from the Regional Committee on Health Research Ethics for Southern Denmark approval ID S-20162000-40 and the Danish Data Protection Agency approval ID 16/15491). The study was deemed not notifiable by both authorities. NCT02894346; Pre-results. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.
Highly linear, sensitive analog-to-digital converter
NASA Technical Reports Server (NTRS)
Cox, J.; Finley, W. R.
1969-01-01
Analog-to-digital converter converts 10 volt full scale input signal into 13 bit digital output. Advantages include high sensitivity, linearity, low quantitizing error, high resistance to mechanical shock and vibration loads, and temporary data storage capabilities.
19 CFR 206.34 - Contents of petition.
Code of Federal Regulations, 2014 CFR
2014-04-01
... paragraph (c) of this section; (e) Data showing injury. Quantitative data for each of the most recent 5 full... levels of expenditures for research and development; (iii) The extent to which the U.S. market is the...
19 CFR 206.34 - Contents of petition.
Code of Federal Regulations, 2012 CFR
2012-04-01
... paragraph (c) of this section; (e) Data showing injury. Quantitative data for each of the most recent 5 full... levels of expenditures for research and development; (iii) The extent to which the U.S. market is the...
19 CFR 206.34 - Contents of petition.
Code of Federal Regulations, 2013 CFR
2013-04-01
... paragraph (c) of this section; (e) Data showing injury. Quantitative data for each of the most recent 5 full... levels of expenditures for research and development; (iii) The extent to which the U.S. market is the...
Quantitative X-ray Differential Interference Contrast Microscopy
NASA Astrophysics Data System (ADS)
Nakamura, Takashi
Full-field soft x-ray microscopes are widely used in many fields of sciences. Advances in nanofabrication technology enabled short wavelength focusing elements with significantly improved spatial resolution. In the soft x-ray spectral region, samples as small as 12 nm can be resolved using micro zone-plates as the objective lens. In addition to conventional x-ray microscopy in which x-ray absorption difference provides the image contrast, phase contrast mechanisms such as differential phase contrast (DIC) and Zernike phase contrast have also been demonstrated These phase contrast imaging mechanisms are especially attractive at the x-ray wavelengths where phase contrast of most materials is typically 10 times stronger than the absorption contrast. With recent progresses in plasma-based x- ray sources and increasing accessibility to synchrotron user facilities, x-ray microscopes are quickly becoming standard measurement equipment in the laboratory. To further the usefulness of x-ray DIC microscopy this thesis explicitly addresses three known issues with this imaging modality by introducing new techniques and devices First, as opposed to its visible-light counterpart, no quantitative phase imaging technique exists for x-ray DIC microscopy. To address this issue, two nanoscale x-ray quantitative phase imaging techniques, using exclusive OR (XOR) patterns and zone-plate doublets, respectively, are proposed. Unlike existing x-ray quantitative phase imaging techniques such as Talbot interferometry and ptychography, no dedicated experimental setups or stringent illumination coherence are needed for quantitative phase retrieval. Second, to the best of our knowledge, no quantitative performance characterization of DIC microscopy exists to date. Therefore the imaging system's response to sample's spatial frequency is not known In order to gain in-depth understanding of this imaging modality, performance of x-ray DIC microscopy is quantified using modulation transfer function. A new illumination apparatus required for the transfer function analysis under partially coherent illumination is also proposed. Such a characterization is essential for a proper selection of DIC optics for various transparent samples under study. Finally, optical elements used for x-ray DIC microscopy are highly absorptive and high brilliance x-ray sources such as synchrotrons are generally needed for image contrast. To extend the use of x-ray DIC microscopy to a wider variety of applications, a high efficiency large numerical aperture optical element consisting of high reflective Bragg reflectors is proposed. Using Bragg reflectors, which have 70% ˜99% reflectivity at extreme ultraviolet and soft x-rays for all angles of glancing incidence, the first order focusing efficiency is expected to increase by ˜ 8 times compared to that of a typical Fresnel zone-plate. This thesis contributes to current nanoscale x-ray phase contrast imaging research and provides new insights for biological, material, and magnetic sciences
Enamel color changes following orthodontic treatment.
Pandian, Akshaya; Ranganathan, Sukanya; Padmanabhan, Sridevi
2017-01-01
To evaluate and compare the effect of various orthodontic bonding systems and clean up procedures on quantitative enamel colour change. A literature search was done to identify the studies that assessed the quantitative enamel colour change associated with the various bonding systems and cleanup procedures. Electronic database (Pub Med, Cochrane and Google Scholar) were searched. First stage screening was performed and the abstracts were selected according to the initial selection criteria. Full text articles were retrieved and analyzed during second stage screening. The bibliographies were reviewed to identify additional relevant studies. Sixteen full text articles were retrieved. Six were rejected because the methodology was different. There was significant enamel colour change following orthodontic bonding, debonding and clean up procedures. Self-etching primers produce less enamel colour change compared to conventional etching. Resin Modified GIC produces least colour change compared to other light cure and chemical cure systems. Polishing following the clean-up procedure reduces the colour change of the enamel.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Walker, Bennett N., E-mail: bennett.walker@fda.hhs.gov; Office of Device Evaluation, Center for Devices and Radiological Health, U.S. Food and Drug Administration, Silver Spring, Maryland 20993; James, Robert H.
Glare, glistenings, optical defects, dysphotopsia, and poor image quality are a few of the known deficiencies of intraocular lenses (IOLs). All of these optical phenomena are related to light scatter. However, the specific direction that light scatters makes a critical difference between debilitating glare and a slightly noticeable decrease in image quality. Consequently, quantifying the magnitude and direction of scattered light is essential to appropriately evaluate the safety and efficacy of IOLs. In this study, we introduce a full-angle scanning light scattering profiler (SLSP) as a novel approach capable of quantitatively evaluating the light scattering from IOLs with a nearlymore » 360° view. The SLSP method can simulate in situ conditions by controlling the parameters of the light source including angle of incidence. This testing strategy will provide a more effective nonclinical approach for the evaluation of IOL light scatter.« less
Solid-state NMR studies of proteins immobilized on inorganic surfaces
Shaw, Wendy J.
2014-10-29
Solid state NMR is the primary tool for studying the quantitative, site-specific structure, orientation, and dynamics of biomineralization proteins under biologically relevant conditions. Two calcium phosphate proteins, statherin and leucine rich amelogenin protein (LRAP), have been studied in depth and have different features, challenging our ability to extract design principles. More recent studies of the significantly larger full-length amelogenin represent a challenging but necessary step to ultimately investigate the full diversity of biomineralization proteins. Interactions of amino acids and silaffin peptide with silica are also being studied, along with qualitative studies of proteins interacting with calcium carbonate. Dipolar recoupling techniquesmore » have formed the core of the quantitative studies, yet, the need for isolated spin pairs makes this approach costly and time intensive. The use of multi-dimensional techniques is advancing, methodology which, despite its challenges with these difficult-to-study proteins, will continue to drive future advancements in this area.« less
Tang, L.; Sun, Y.; Buelow, D.; Gu, Z.; Caliendo, A. M.; Pounds, S.
2016-01-01
Given recent advances in the development of quantitative standards, particularly WHO international standards, efforts to better understand the commutability of reference materials have been made. Existing approaches in evaluating commutability include prediction intervals and correspondence analysis; however, the results obtained from existing approaches may be ambiguous. We have developed a “deviation-from-ideal” (DFI) approach to evaluate commutability of standards and applied it to the assessment of Epstein-Bar virus (EBV) load testing in four quantitative PCR assays, treating digital PCR as a reference assay. We then discuss advantages and limitations of the DFI approach as well as experimental design to best evaluate the commutability of an assay in practice. PMID:27076654
Quantitative imaging of mammalian transcriptional dynamics: from single cells to whole embryos.
Zhao, Ziqing W; White, Melanie D; Bissiere, Stephanie; Levi, Valeria; Plachta, Nicolas
2016-12-23
Probing dynamic processes occurring within the cell nucleus at the quantitative level has long been a challenge in mammalian biology. Advances in bio-imaging techniques over the past decade have enabled us to directly visualize nuclear processes in situ with unprecedented spatial and temporal resolution and single-molecule sensitivity. Here, using transcription as our primary focus, we survey recent imaging studies that specifically emphasize the quantitative understanding of nuclear dynamics in both time and space. These analyses not only inform on previously hidden physical parameters and mechanistic details, but also reveal a hierarchical organizational landscape for coordinating a wide range of transcriptional processes shared by mammalian systems of varying complexity, from single cells to whole embryos.
Measurement of student attitudes in first year engineering - A mixed methods approach
NASA Astrophysics Data System (ADS)
Malik, Qaiser Hameed
This research study focused on freshman attitudes towards engineering in a newly implemented cornerstone sequence that emphasized holistic design experiences. The students' initial attitudes and changes in these attitudes were examined with the explanatory mixed methods approach that allows a sequential examination of the target population with two methods, using two sets of data, to investigate the treatment effects. In the quantitative phase, the study compared changes in freshman attitude towards engineering, between the new 'design sequence' group (composed of freshmen in the cornerstone sequence) and the prior 'traditional sequence' group (composed of all other freshmen), over the course of one semester. The data were collected in fall 2008 at two time intervals and changes in the two groups' attitudes were examined with repeated measures analysis of covariance models. The analyses reported here include data from 389 students out of the total population of 722 freshmen. The analyses revealed that engineering freshmen joined the program with positive or strongly positive attitudes towards engineering. Those strong attitudes were durable and resistant to change. Students in the design sequence group had higher ACT scores, enjoyed math and science the most, and did not believe engineering to be an exact science. However, no appreciable time-group interaction was observed. To validate the quantitative results, an interview protocol was developed to investigate initial freshman attitudes and changes, if any, that took place as a result of the new cornerstone sequence. One-on-one interviews with a sample of ten students out of the population of 272 freshmen revealed that freshmen in the cornerstone sequence entered the program full of enthusiasm and idealism, and with strongly positive attitudes towards engineering. The strong motivational factors included parental/teacher influences, childhood motivations, and high school extra-curricular experiences. The participants appreciated the team work and problem solving aspects of engineering; however, they reported negative experiences in the cornerstone sequence. Interestingly, their overall perception about engineering was not affected by any of the negative experiences. The qualitative phase substantiated the belief that strong attitudes are harder to change; they are durable, they have impact, and they are not significantly affected by a short treatment. The results of this mixed methods study indicate that changing student attitudes may not be an easy task. One must develop a better understanding of student attitudes in order to improve understanding of the fine-grained details of curriculum and its implementation to be able to develop more effective cornerstone design courses. Clearly, tight and focused quantitative studies complemented with a qualitative component provide a much broader and deeper insight into the learning that takes place in freshman courses. This research also documents the use of a longitudinal study to track the design sequence group and observe their performance in their junior and senior years. This would provide a better understanding of the long term effects of the new sequence.
2013-01-01
Background Obtaining informed consent is a cornerstone of biomedical research, yet participants comprehension of presented information is often low. The most effective interventions to improve understanding rates have not been identified. Purpose To systematically analyze the random controlled trials testing interventions to research informed consent process. The primary outcome of interest was quantitative rates of participant understanding; secondary outcomes were rates of information retention, satisfaction, and accrual. Interventional categories included multimedia, enhanced consent documents, extended discussions, test/feedback quizzes, and miscellaneous methods. Methods The search spanned from database inception through September 2010. It was run on Ovid MEDLINE, Ovid EMBASE, Ovid CINAHL, Ovid PsycInfo and Cochrane CENTRAL, ISI Web of Science and Scopus. Five reviewers working independently and in duplicate screened full abstract text to determine eligibility. We included only RCTs. 39 out of 1523 articles fulfilled review criteria (2.6%), with a total of 54 interventions. A data extraction form was created in Distiller, an online reference management system, through an iterative process. One author collected data on study design, population, demographics, intervention, and analytical technique. Results Meta-analysis was possible on 22 interventions: multimedia, enhanced form, and extended discussion categories; all 54 interventions were assessed by review. Meta-analysis of multimedia approaches was associated with a non-significant increase in understanding scores (SMD 0.30, 95% CI, -0.23 to 0.84); enhanced consent form, with significant increase (SMD 1.73, 95% CI, 0.99 to 2.47); and extended discussion, with significant increase (SMD 0.53, 95% CI, 0.21 to 0.84). By review, 31% of multimedia interventions showed significant improvement in understanding; 41% for enhanced consent form; 50% for extended discussion; 33% for test/feedback; and 29% for miscellaneous.Multiple sources of variation existed between included studies: control processes, the presence of a human proctor, real vs. simulated protocol, and assessment formats. Conclusions Enhanced consent forms and extended discussions were most effective in improving participant understanding. Interventions of all categories had no negative impact on participant satisfaction or study accrual. Identification of best practices for studies of informed consent interventions would aid future systematic comparisons. PMID:23879694
Nishimura, Adam; Carey, Jantey; Erwin, Patricia J; Tilburt, Jon C; Murad, M Hassan; McCormick, Jennifer B
2013-07-23
Obtaining informed consent is a cornerstone of biomedical research, yet participants comprehension of presented information is often low. The most effective interventions to improve understanding rates have not been identified. To systematically analyze the random controlled trials testing interventions to research informed consent process. The primary outcome of interest was quantitative rates of participant understanding; secondary outcomes were rates of information retention, satisfaction, and accrual. Interventional categories included multimedia, enhanced consent documents, extended discussions, test/feedback quizzes, and miscellaneous methods. The search spanned from database inception through September 2010. It was run on Ovid MEDLINE, Ovid EMBASE, Ovid CINAHL, Ovid PsycInfo and Cochrane CENTRAL, ISI Web of Science and Scopus. Five reviewers working independently and in duplicate screened full abstract text to determine eligibility. We included only RCTs. 39 out of 1523 articles fulfilled review criteria (2.6%), with a total of 54 interventions. A data extraction form was created in Distiller, an online reference management system, through an iterative process. One author collected data on study design, population, demographics, intervention, and analytical technique. Meta-analysis was possible on 22 interventions: multimedia, enhanced form, and extended discussion categories; all 54 interventions were assessed by review. Meta-analysis of multimedia approaches was associated with a non-significant increase in understanding scores (SMD 0.30, 95% CI, -0.23 to 0.84); enhanced consent form, with significant increase (SMD 1.73, 95% CI, 0.99 to 2.47); and extended discussion, with significant increase (SMD 0.53, 95% CI, 0.21 to 0.84). By review, 31% of multimedia interventions showed significant improvement in understanding; 41% for enhanced consent form; 50% for extended discussion; 33% for test/feedback; and 29% for miscellaneous.Multiple sources of variation existed between included studies: control processes, the presence of a human proctor, real vs. simulated protocol, and assessment formats. Enhanced consent forms and extended discussions were most effective in improving participant understanding. Interventions of all categories had no negative impact on participant satisfaction or study accrual. Identification of best practices for studies of informed consent interventions would aid future systematic comparisons.
From Frozen Ties to Strategic Engagement: U.S.-Iranian Relationship in 2030
2015-05-01
rest xiv on the principle and practice of selective engagement, but with an understanding and direction to a more full-fledged strategic relationship...likely rest on the principle and practice of selective engagement, but with an understanding and direction to a more full-fledged strategic...occasionally rebuffed U.S. engagement at- tempts, citing Washington’s lack of respect. The lack of understanding in Washington of diverg- ing views of
Characteristics of Early Stages of Corrosion Fatigue in Aircraft Skin
DOT National Transportation Integrated Search
1996-02-01
SRI International is conducting research to characterize and quantitatively describe the early stages of corrosion fatigue in the fuselage skin of commercial aircraft. Specific objectives are to gain an improved deterministic understanding of the tra...
NASA Technical Reports Server (NTRS)
Asner, G. P.; Treuhaft, R. N.; Law, B. E.
2000-01-01
One of today's principle objecdtives of remote sensing is carbon accounting in the world's forests via biomass monitoring. Determining carbon sequestration by forest ecosystems requires understanding the carbon budgets of these ecosystems.
Dataglove measurement of joint angles in sign language handshapes
Eccarius, Petra; Bour, Rebecca; Scheidt, Robert A.
2012-01-01
In sign language research, we understand little about articulatory factors involved in shaping phonemic boundaries or the amount (and articulatory nature) of acceptable phonetic variation between handshapes. To date, there exists no comprehensive analysis of handshape based on the quantitative measurement of joint angles during sign production. The purpose of our work is to develop a methodology for collecting and visualizing quantitative handshape data in an attempt to better understand how handshapes are produced at a phonetic level. In this pursuit, we seek to quantify the flexion and abduction angles of the finger joints using a commercial data glove (CyberGlove; Immersion Inc.). We present calibration procedures used to convert raw glove signals into joint angles. We then implement those procedures and evaluate their ability to accurately predict joint angle. Finally, we provide examples of how our recording techniques might inform current research questions. PMID:23997644
Urban Multisensory Laboratory, AN Approach to Model Urban Space Human Perception
NASA Astrophysics Data System (ADS)
González, T.; Sol, D.; Saenz, J.; Clavijo, D.; García, H.
2017-09-01
An urban sensory lab (USL or LUS an acronym in Spanish) is a new and avant-garde approach for studying and analyzing a city. The construction of this approach allows the development of new methodologies to identify the emotional response of public space users. The laboratory combines qualitative analysis proposed by urbanists and quantitative measures managed by data analysis applications. USL is a new approach to go beyond the borders of urban knowledge. The design thinking strategy allows us to implement methods to understand the results provided by our technique. In this first approach, the interpretation is made by hand. However, our goal is to combine design thinking and machine learning in order to analyze the qualitative and quantitative data automatically. Now, the results are being used by students from the Urbanism and Architecture courses in order to get a better understanding of public spaces in Puebla, Mexico and its interaction with people.
Kodra, Evan; Chen, Stone; Sheldon, Seth; Zik, Ory
2018-01-01
Individuals must have a quantitative understanding of the carbon footprint tied to their everyday decisions to make efficient sustainable decisions. We report research of the innumeracy of individuals as it relates to their carbon footprint. In three studies that varied in terms of scale and sample, respondents estimate the quantity of CO2 released when combusting a gallon of gasoline in comparison to several well-known metrics including food calories and travel distance. Consistently, respondents estimated the quantity of CO2 from gasoline compared to other metrics with significantly less accuracy while exhibiting a tendency to underestimate CO2. Such relative absence of carbon numeracy of even a basic consumption habit may limit the effectiveness of environmental policies and campaigns aimed at changing individual behavior. We discuss several caveats as well as opportunities for policy design that could aid the improvement of people’s quantitative understanding of their carbon footprint. PMID:29723206
The memory remains: Understanding collective memory in the digital age
García-Gavilanes, Ruth; Mollgaard, Anders; Tsvetkova, Milena; Yasseri, Taha
2017-01-01
Recently developed information communication technologies, particularly the Internet, have affected how we, both as individuals and as a society, create, store, and recall information. The Internet also provides us with a great opportunity to study memory using transactional large-scale data in a quantitative framework similar to the practice in natural sciences. We make use of online data by analyzing viewership statistics of Wikipedia articles on aircraft crashes. We study the relation between recent events and past events and particularly focus on understanding memory-triggering patterns. We devise a quantitative model that explains the flow of viewership from a current event to past events based on similarity in time, geography, topic, and the hyperlink structure of Wikipedia articles. We show that, on average, the secondary flow of attention to past events generated by these remembering processes is larger than the primary attention flow to the current event. We report these previously unknown cascading effects. PMID:28435881
NASA Astrophysics Data System (ADS)
Tsuruoka, Masako; Shibasaki, Ryosuke; Box, Elgene O.; Murai, Shunji; Mori, Eiji; Wada, Takao; Kurita, Masahiro; Iritani, Makoto; Kuroki, Yoshikatsu
1994-08-01
In medical rehabilitation science, quantitative understanding of patient movement in 3-D space is very important. The patient with any joint disorder will experience its influence on other body parts in daily movement. The alignment of joints in movement is able to improve under medical therapy process. In this study, the newly developed system is composed of two non- metri CCD video cameras and a force plate sensor, which are controlled simultaneously by a personal computer. By this system time-series digital data from 3-D image photogrammetry, each foot pressure and its center position, is able to provide efficient information for biomechanical and mathematical analysis of human movement. Each specific and common points are indicated in any patient movement. This study suggests more various, quantitative understanding in medical rehabilitation science.
NASA Astrophysics Data System (ADS)
Zhang, Lin
2014-02-01
Educators design and create various technology tools to scaffold students' learning. As more and more technology designs are incorporated into learning, growing attention has been paid to the study of technology-based learning tool. This paper discusses the emerging issues, such as how can learning effectiveness be understood in relation to different technology features? And how can pieces of qualitative and quantitative results be integrated to achieve a broader understanding of technology designs? To address these issues, this paper proposes a meta-analysis method. Detailed explanations about the structure of the methodology and its scientific mechanism are provided for discussions and suggestions. This paper ends with an in-depth discussion on the concerns and questions that educational researchers might raise, such as how this methodology takes care of learning contexts.
Risks, risk assessment and risk competence in toxicology
Stahlmann, Ralf; Horvath, Aniko
2015-01-01
Understanding the toxic effects of xenobiotics requires sound knowledge of physiology and biochemistry. The often described lack of understanding pharmacology/toxicology is therefore primarily caused by the general absence of the necessary fundamental knowledge. Since toxic effects depend on exposure (or dosage) assessing the risks arising from toxic substances also requires quantitative reasoning. Typically public discussions nearly always neglect quantitative aspects and laypersons tend to disregard dose-effect-relationships. One of the main reasons for such disregard is the fact that exposures often occur at extremely low concentrations that can only be perceived intellectually but not by the human senses. However, thresholds in the low exposure range are often scientifically disputed. At the same time, ignorance towards known dangers is wide-spread. Thus, enhancing the risk competence of laypersons will have to be initially restricted to increasing the awareness of existing problems. PMID:26195922
Wang, Shuihua; Chen, Mengmeng; Li, Yang; Shao, Ying; Zhang, Yudong; Du, Sidan; Wu, Jane
2016-01-01
Dendritic spines are described as neuronal protrusions. The morphology of dendritic spines and dendrites has a strong relationship to its function, as well as playing an important role in understanding brain function. Quantitative analysis of dendrites and dendritic spines is essential to an understanding of the formation and function of the nervous system. However, highly efficient tools for the quantitative analysis of dendrites and dendritic spines are currently undeveloped. In this paper we propose a novel three-step cascaded algorithm-RTSVM- which is composed of ridge detection as the curvature structure identifier for backbone extraction, boundary location based on differences in density, the Hu moment as features and Twin Support Vector Machine (TSVM) classifiers for spine classification. Our data demonstrates that this newly developed algorithm has performed better than other available techniques used to detect accuracy and false alarm rates. This algorithm will be used effectively in neuroscience research.
Liu, Zhen; Li, Ping; Bian, Weiwei; Yu, Jingkai; Zhan, Jinhua
2016-01-01
Surface oxidation states of ultrafine particulate matter can influence the proinflammatory responses and reactive oxygen species levels in tissue. Surface active species of vehicle-emission soot can serve as electron transfer-mediators in mitochondrion. Revealing the role of surface oxidation state in particles-proteins interaction will promote the understanding on metabolism and toxicity. Here, the surface oxidation state was modeled by nitro/amino ligands on nanoparticles, the interaction with blood proteins were evaluated by capillary electrophoresis quantitatively. The nitro shown larger affinity than amino. On the other hand, the affinity to hemoglobin is 103 times larger than that to BSA. Further, molecular docking indicated the difference of binding intensity were mainly determined by hydrophobic forces and hydrogen bonds. These will deepen the quantitative understanding of protein-nanoparticles interaction from the perspective of surface chemical state. PMID:27181651
Geospatial Resource Access Analysis In Hedaru, Tanzania
NASA Astrophysics Data System (ADS)
Clark, Dylan G.; Premkumar, Deepak; Mazur, Robert; Kisimbo, Elibariki
2013-12-01
Populations around the world are facing increased impacts of anthropogenic-induced environmental changes and rapid population movements. These environmental and social shifts are having an elevated impact on the livelihoods of agriculturalists and pastoralists in developing countries. This appraisal integrates various tools—usually used independently— to gain a comprehensive understanding of the regional livelihood constraints in the rural Hedaru Valley of northeastern Tanzania. Conducted in three villages with different natural resources, using three primary methods: 1) participatory mapping of infrastructures; 2) administration of quantitative, spatially-tied surveys (n=80) and focus groups (n=14) that examined land use, household health, education, and demographics; 3) conducting quantitative time series analysis of Landsat- based Normalized Difference Vegetation Index images. Through various geospatial and multivariate linear regression analyses, significant geospatial trends emerged. This research added to the academic understanding of the region while establishing pathways for climate change adaptation strategies.
The memory remains: Understanding collective memory in the digital age.
García-Gavilanes, Ruth; Mollgaard, Anders; Tsvetkova, Milena; Yasseri, Taha
2017-04-01
Recently developed information communication technologies, particularly the Internet, have affected how we, both as individuals and as a society, create, store, and recall information. The Internet also provides us with a great opportunity to study memory using transactional large-scale data in a quantitative framework similar to the practice in natural sciences. We make use of online data by analyzing viewership statistics of Wikipedia articles on aircraft crashes. We study the relation between recent events and past events and particularly focus on understanding memory-triggering patterns. We devise a quantitative model that explains the flow of viewership from a current event to past events based on similarity in time, geography, topic, and the hyperlink structure of Wikipedia articles. We show that, on average, the secondary flow of attention to past events generated by these remembering processes is larger than the primary attention flow to the current event. We report these previously unknown cascading effects.
Quantitating T cell cross-reactivity for unrelated peptide antigens.
Ishizuka, Jeffrey; Grebe, Kristie; Shenderov, Eugene; Peters, Bjoern; Chen, Qiongyu; Peng, Yanchun; Wang, Lili; Dong, Tao; Pasquetto, Valerie; Oseroff, Carla; Sidney, John; Hickman, Heather; Cerundolo, Vincenzo; Sette, Alessandro; Bennink, Jack R; McMichael, Andrew; Yewdell, Jonathan W
2009-10-01
Quantitating the frequency of T cell cross-reactivity to unrelated peptides is essential to understanding T cell responses in infectious and autoimmune diseases. Here we used 15 mouse or human CD8+ T cell clones (11 antiviral, 4 anti-self) in conjunction with a large library of defined synthetic peptides to examine nearly 30,000 TCR-peptide MHC class I interactions for cross-reactions. We identified a single cross-reaction consisting of an anti-self TCR recognizing a poxvirus peptide at relatively low sensitivity. We failed to identify any cross-reactions between the synthetic peptides in the panel and polyclonal CD8+ T cells raised to viral or alloantigens. These findings provide the best estimate to date of the frequency of T cell cross-reactivity to unrelated peptides ( approximately 1/30,000), explaining why cross-reactions between unrelated pathogens are infrequently encountered and providing a critical parameter for understanding the scope of self-tolerance.
Quantitating T Cell Cross-Reactivity for Unrelated Peptide Antigens1
Ishizuka, Jeffrey; Grebe, Kristie; Shenderov, Eugene; Peters, Bjoern; Chen, Qiongyu; Peng, YanChun; Wang, Lili; Dong, Tao; Pasquetto, Valerie; Osroff, Carla; Sidney, John; Hickman, Heather; Cerundolo, Vincenzo; Sette, Alessandro; Bennink, Jack R.; McMchael, Andrew; Yewdell, Jonathan W.
2009-01-01
Quantitating the frequency of T cell cross-reactivity to unrelated peptides is essential to understanding T cell responses in infectious and autoimmune diseases. Here we used 15 mouse or human CD8+ T cell clones (11 antiviral, 4 anti-self) in conjunction with a large library of defined synthetic peptides to examine nearly 30,000 TCR-peptide MHC class I interactions for cross-reactions. We identified a single cross-reaction consisting of an anti-self TCR recognizing a poxvirus peptide at relatively low sensitivity. We failed to identify any cross-reactions between the synthetic peptides in the panel and polyclonal CD8+ T cells raised to viral or alloantigens. These findings provide the best estimate to date of the frequency of T cell cross-reactivity to unrelated peptides (∼1/30,000), explaining why cross-reactions between unrelated pathogens are infrequently encountered and providing a critical parameter for understanding the scope of self-tolerance. PMID:19734234
Systems Biology-Driven Hypotheses Tested In Vivo: The Need to Advancing Molecular Imaging Tools.
Verma, Garima; Palombo, Alessandro; Grigioni, Mauro; La Monaca, Morena; D'Avenio, Giuseppe
2018-01-01
Processing and interpretation of biological images may provide invaluable insights on complex, living systems because images capture the overall dynamics as a "whole." Therefore, "extraction" of key, quantitative morphological parameters could be, at least in principle, helpful in building a reliable systems biology approach in understanding living objects. Molecular imaging tools for system biology models have attained widespread usage in modern experimental laboratories. Here, we provide an overview on advances in the computational technology and different instrumentations focused on molecular image processing and analysis. Quantitative data analysis through various open source software and algorithmic protocols will provide a novel approach for modeling the experimental research program. Besides this, we also highlight the predictable future trends regarding methods for automatically analyzing biological data. Such tools will be very useful to understand the detailed biological and mathematical expressions under in-silico system biology processes with modeling properties.
Understanding neighbourhoods, communities and environments: new approaches for social work research.
Holland, Sally; Burgess, Stephen; Grogan-Kaylor, Andy; Delva, Jorge
2010-06-01
This article discusses some new ways in which social work research can explore the interaction between neighbourhoods and child and adult wellbeing. The authors note that social work practices are often criticised for taking an individualistic approach and paying too little attention to the service user's environment. The article uses examples of research projects from Chile, the United States of America and Wales, to discuss the use of spatially oriented research methods for understanding neighbourhood factors. Quantitative, qualitative and mixed methods approaches that are particularly appropriate for investigating social work relevant topics are discussed in turn, including quantitative and qualitative uses for geographical information systems (GIS), hierarchical linear modelling (HLM) for analysing spatially clustered data and qualitative mobile interviews. The article continues with a discussion of the strengths and limitations of using spatially orientated research designs in social work research settings and concludes optimistically with suggestions for future directions in this area.
Understanding Student Article Retrieval Behaviors: Instructional Implications
ERIC Educational Resources Information Center
Cook-Cottone, Catherine P.; Dutt-Doner, Karen; Schoen, David
2005-01-01
This study evaluates the use of full-text databases amongst 425 undergraduate and graduate students in western New York. A review of literature implicated convenience, time issues, article retrieval option knowledge, and the appreciation and understanding of research article quality as potential predictors of full-text reliance. These variables…
Modeling noisy resonant system response
NASA Astrophysics Data System (ADS)
Weber, Patrick Thomas; Walrath, David Edwin
2017-02-01
In this paper, a theory-based model replicating empirical acoustic resonant signals is presented and studied to understand sources of noise present in acoustic signals. Statistical properties of empirical signals are quantified and a noise amplitude parameter, which models frequency and amplitude-based noise, is created, defined, and presented. This theory-driven model isolates each phenomenon and allows for parameters to be independently studied. Using seven independent degrees of freedom, this model will accurately reproduce qualitative and quantitative properties measured from laboratory data. Results are presented and demonstrate success in replicating qualitative and quantitative properties of experimental data.
Epigenetics meets mathematics: towards a quantitative understanding of chromatin biology.
Steffen, Philipp A; Fonseca, João P; Ringrose, Leonie
2012-10-01
How fast? How strong? How many? So what? Why do numbers matter in biology? Chromatin binding proteins are forever in motion, exchanging rapidly between bound and free pools. How do regulatory systems whose components are in constant flux ensure stability and flexibility? This review explores the application of quantitative and mathematical approaches to mechanisms of epigenetic regulation. We discuss methods for measuring kinetic parameters and protein quantities in living cells, and explore the insights that have been gained by quantifying and modelling dynamics of chromatin binding proteins. Copyright © 2012 WILEY Periodicals, Inc.
MR Imaging-based Semi-quantitative Methods for Knee Osteoarthritis
JARRAYA, Mohamed; HAYASHI, Daichi; ROEMER, Frank Wolfgang; GUERMAZI, Ali
2016-01-01
Magnetic resonance imaging (MRI)-based semi-quantitative (SQ) methods applied to knee osteoarthritis (OA) have been introduced during the last decade and have fundamentally changed our understanding of knee OA pathology since then. Several epidemiological studies and clinical trials have used MRI-based SQ methods to evaluate different outcome measures. Interest in MRI-based SQ scoring system has led to continuous update and refinement. This article reviews the different SQ approaches for MRI-based whole organ assessment of knee OA and also discuss practical aspects of whole joint assessment. PMID:26632537
Liu, Tong; Song, Deli; Dong, Jianzeng; Zhu, Pinghui; Liu, Jie; Liu, Wei; Ma, Xiaohai; Zhao, Lei; Ling, Shukuan
2017-01-01
Myocardial fibrosis is an important part of cardiac remodeling that leads to heart failure and death. Myocardial fibrosis results from increased myofibroblast activity and excessive extracellular matrix deposition. Various cells and molecules are involved in this process, providing targets for potential drug therapies. Currently, the main detection methods of myocardial fibrosis rely on serum markers, cardiac magnetic resonance imaging, and endomyocardial biopsy. This review summarizes our current knowledge regarding the pathophysiology, quantitative assessment, and novel therapeutic strategies of myocardial fibrosis. PMID:28484397
Nayak, Satyaprakash; Sander, Oliver; Al‐Huniti, Nidal; de Alwis, Dinesh; Chain, Anne; Chenel, Marylore; Sunkaraneni, Soujanya; Agrawal, Shruti; Gupta, Neeraj
2018-01-01
Quantitative pharmacology (QP) applications in translational medicine, drug‐development, and therapeutic use were crowd‐sourced by the ASCPT Impact and Influence initiative. Highlighted QP case studies demonstrated faster access to innovative therapies for patients through 1) rational dose selection for pivotal trials; 2) reduced trial‐burden for vulnerable populations; or 3) simplified posology. Critical success factors were proactive stakeholder engagement, alignment on the value of model‐informed approaches, and utilizing foundational clinical pharmacology understanding of the therapy. PMID:29330855
Food activities and identity maintenance in old age: a systematic review and meta-synthesis.
Plastow, Nicola Ann; Atwal, Anita; Gilhooly, Mary
2015-01-01
Services provided to older people should be developed based on active ageing policies. Nutrition is one aspect of active ageing, but little is known about how food activities contribute to psychological well-being in later life. This is a systematic review of qualitative and quantitative research that answers the question 'What is known about the relationship between food activities and the maintenance of identities in old age?'. We followed the preferred reporting items for systematic reviews and meta-analyses guidelines and used quality assessment parameters to complete a systematic review and narrative synthesis. Academic Search Premier, MEDLINE, CINAHL Plus, and PsycINFO databases were searched. We initially identified 8016 articles, of which 167 full-text articles were screened for inclusion. Twenty-two articles were included in the review. There was moderate evidence from nine qualitative and two quantitative studies, of variable quality, that food activities contribute to the maintenance of women's gendered identities, the ethnic identities of men and women, and community identities. There was moderate evidence from 10 qualitative studies, of variable quality, that a change in food choice and deteriorating health changed food activity participation. These changes threatened identities. Most studies included both younger adults and older adults. In later life, there are many life experiences leading to change. Further research is needed to develop understanding of how identity and mental well-being are maintained, despite changes in everyday activities like cooking and eating. This may enable health care professionals to meet psychological needs alongside biological needs during nutritional interventions.
NASA Astrophysics Data System (ADS)
Barroso Peña, Alvaro; Grüner, Malte; Forbes, Taylor; Denz, Cornelia; Strassert, Cristian A.
2016-09-01
Antimicrobial Photodynamic Inactivation (PDI) represents an attractive alternative in the treatment of infections by antibiotic-resistant pathogenic bacteria. In PDI a photosensitizer (PS) is administered to the site of the biological target in order to generate cytotoxic singlet oxygen which reacts with the biological membrane upon application of harmless visible light. Established methods for testing the photoinduced cytotoxicity of PSs rely on the observation of the whole bacterial ensemble providing only a population-averaged information about the overall produced toxicity. However, for a deeper understanding of the processes that take place in PDI, new methods are required that provide simultaneous regulation of the ROS production, monitoring the subsequent damage induced in the bacteria cells, and full control of the distance between the bacteria and the center of the singlet oxygen production. Herein we present a novel method that enables the quantitative spatio-time-resolved analysis at the single cell level of the photoinduced damage produced by transparent microspheres functionalized with PSs. For this purpose, a methodology was introduced to monitor phototriggered changes with spatiotemporal resolution employing holographic optical tweezers and functional fluorescence microscopy. The defined distance between the photoactive particles and individual bacteria can be fixed under the microscope before the photosensitization process, and the photoinduced damage is monitored by tracing the fluorescence turn-on of a suitable marker. Our methodology constitutes a new tool for the in vitro design and analysis of photosensitizers, as it enables a quantitative response evaluation of living systems towards oxidative stress.
Almstrand, Robert; Daims, Holger; Persson, Frank; Sörensson, Fred
2013-01-01
In biofilms, microbial activities form gradients of substrates and electron acceptors, creating a complex landscape of microhabitats, often resulting in structured localization of the microbial populations present. To understand the dynamic interplay between and within these populations, quantitative measurements and statistical analysis of their localization patterns within the biofilms are necessary, and adequate automated tools for such analyses are needed. We have designed and applied new methods for fluorescence in situ hybridization (FISH) and digital image analysis of directionally dependent (anisotropic) multispecies biofilms. A sequential-FISH approach allowed multiple populations to be detected in a biofilm sample. This was combined with an automated tool for vertical-distribution analysis by generating in silico biofilm slices and the recently developed Inflate algorithm for coaggregation analysis of microbial populations in anisotropic biofilms. As a proof of principle, we show distinct stratification patterns of the ammonia oxidizers Nitrosomonas oligotropha subclusters I and II and the nitrite oxidizer Nitrospira sublineage I in three different types of wastewater biofilms, suggesting niche differentiation between the N. oligotropha subclusters, which could explain their coexistence in the same biofilms. Coaggregation analysis showed that N. oligotropha subcluster II aggregated closer to Nitrospira than did N. oligotropha subcluster I in a pilot plant nitrifying trickling filter (NTF) and a moving-bed biofilm reactor (MBBR), but not in a full-scale NTF, indicating important ecophysiological differences between these phylogenetically closely related subclusters. By using high-resolution quantitative methods applicable to any multispecies biofilm in general, the ecological interactions of these complex ecosystems can be understood in more detail. PMID:23892743
GiA Roots: software for the high throughput analysis of plant root system architecture.
Galkovskyi, Taras; Mileyko, Yuriy; Bucksch, Alexander; Moore, Brad; Symonova, Olga; Price, Charles A; Topp, Christopher N; Iyer-Pascuzzi, Anjali S; Zurek, Paul R; Fang, Suqin; Harer, John; Benfey, Philip N; Weitz, Joshua S
2012-07-26
Characterizing root system architecture (RSA) is essential to understanding the development and function of vascular plants. Identifying RSA-associated genes also represents an underexplored opportunity for crop improvement. Software tools are needed to accelerate the pace at which quantitative traits of RSA are estimated from images of root networks. We have developed GiA Roots (General Image Analysis of Roots), a semi-automated software tool designed specifically for the high-throughput analysis of root system images. GiA Roots includes user-assisted algorithms to distinguish root from background and a fully automated pipeline that extracts dozens of root system phenotypes. Quantitative information on each phenotype, along with intermediate steps for full reproducibility, is returned to the end-user for downstream analysis. GiA Roots has a GUI front end and a command-line interface for interweaving the software into large-scale workflows. GiA Roots can also be extended to estimate novel phenotypes specified by the end-user. We demonstrate the use of GiA Roots on a set of 2393 images of rice roots representing 12 genotypes from the species Oryza sativa. We validate trait measurements against prior analyses of this image set that demonstrated that RSA traits are likely heritable and associated with genotypic differences. Moreover, we demonstrate that GiA Roots is extensible and an end-user can add functionality so that GiA Roots can estimate novel RSA traits. In summary, we show that the software can function as an efficient tool as part of a workflow to move from large numbers of root images to downstream analysis.
Halley-Stott, R.P.; Pasque, V.; Astrand, C.; Miyamoto, K.; Simeoni, I.; Jullien, J.; Gurdon, J.B.
2010-01-01
Full-grown Xenopus oocytes in first meiotic prophase contain an immensely enlarged nucleus, the Germinal Vesicle (GV), that can be injected with several hundred somatic cell nuclei. When the nuclei of mammalian somatic cells or cultured cell lines are injected into a GV, a wide range of genes that are not transcribed in the donor cells, including pluripotency genes, start to be transcriptionally activated, and synthesize primary transcripts continuously for several days. Because of the large size and abundance of Xenopus laevis oocytes, this experimental system offers an opportunity to understand the mechanisms by which somatic cell nuclei can be reprogrammed to transcribe genes characteristic of oocytes and early embryos. The use of mammalian nuclei ensures that there is no background of endogenous maternal transcripts of the kind that are induced. The induced gene transcription takes place in the absence of cell division or DNA synthesis and does not require protein synthesis. Here we summarize new as well as established results that characterize this experimental system. In particular, we describe optimal conditions for transplanting somatic nuclei to oocytes and for the efficient activation of transcription by transplanted nuclei. We make a quantitative determination of transcript numbers for pluripotency and housekeeping genes, comparing cultured somatic cell nuclei with those of embryonic stem cells. Surprisingly we find that the transcriptional activation of somatic nuclei differs substantially from one donor cell-type to another and in respect of different pluripotency genes. We also determine the efficiency of an injected mRNA translation into protein. PMID:20123126
Yang, Dong-Ping; Robinson, P A
2017-04-01
A physiologically based corticothalamic model of large-scale brain activity is used to analyze critical dynamics of transitions from normal arousal states to epileptic seizures, which correspond to Hopf bifurcations. This relates an abstract normal form quantitatively to underlying physiology that includes neural dynamics, axonal propagation, and time delays. Thus, a bridge is constructed that enables normal forms to be used to interpret quantitative data. The normal form of the Hopf bifurcations with delays is derived using Hale's theory, the center manifold theorem, and normal form analysis, and it is found to be explicitly expressed in terms of transfer functions and the sensitivity matrix of a reduced open-loop system. It can be applied to understand the effect of each physiological parameter on the critical dynamics and determine whether the Hopf bifurcation is supercritical or subcritical in instabilities that lead to absence and tonic-clonic seizures. Furthermore, the effects of thalamic and cortical nonlinearities on the bifurcation type are investigated, with implications for the roles of underlying physiology. The theoretical predictions about the bifurcation type and the onset dynamics are confirmed by numerical simulations and provide physiologically based criteria for determining bifurcation types from first principles. The results are consistent with experimental data from previous studies, imply that new regimes of seizure transitions may exist in clinical settings, and provide a simplified basis for control-systems interventions. Using the normal form, and the full equations from which it is derived, more complex dynamics, such as quasiperiodic cycles and saddle cycles, are discovered near the critical points of the subcritical Hopf bifurcations.
Alexanders, Jenny; Anderson, Anna; Henderson, Sarah
2015-06-01
Research has demonstrated that incorporating psychological interventions within physiotherapy practice has numerous potential benefits. Despite this physiotherapists have reported feeling inadequately trained to confidently use such interventions in their day-to-day practice. To systematically review musculoskeletal physiotherapists' perceptions regarding the use of psychological interventions within physiotherapy practice. Eligible studies were identified through a rigorous search of AMED, CINAHL, EMBASE, MEDLINE and PsychINFO from January 2002 until August 2013. Full text qualitative, quantitative and mixed methodology studies published in English language investigating musculoskeletal physiotherapists' perceptions regarding their use of psychological interventions within physiotherapy practice. Included studies were appraised for risk of bias using the Critical Appraisal Skills Programme qualitative checklist. Meta-analysis was not possible due to study heterogeneity. Six studies, all with a low risk of bias, met the inclusion criteria. These studies highlighted that physiotherapists appreciate the importance of using psychological interventions within their practice, but report inadequate understanding and consequent underutilisation of these interventions. These results should be noted with some degree of caution due to various limitations associated with the included studies and with this review, including the use of a qualitative appraisal tool for mixed methodology/quantitative studies. These findings suggest that musculoskeletal physiotherapists are aware of the potential benefits of incorporating psychological interventions within their practice but feel insufficiently trained to optimise their use of such interventions; hence highlighting a need for further research in this area and a review of physiotherapist training. Copyright © 2014 Chartered Society of Physiotherapy. Published by Elsevier Ltd. All rights reserved.
Comprehensive genetic dissection of wood properties in a widely-grown tropical tree: Eucalyptus
2011-01-01
Background Eucalyptus is an important genus in industrial plantations throughout the world and is grown for use as timber, pulp, paper and charcoal. Several breeding programmes have been launched worldwide to concomitantly improve growth performance and wood properties (WPs). In this study, an interspecific cross between Eucalyptus urophylla and E. grandis was used to identify major genomic regions (Quantitative Trait Loci, QTL) controlling the variability of WPs. Results Linkage maps were generated for both parent species. A total of 117 QTLs were detected for a series of wood and end-use related traits, including chemical, technological, physical, mechanical and anatomical properties. The QTLs were mainly clustered into five linkage groups. In terms of distribution of QTL effects, our result agrees with the typical L-shape reported in most QTL studies, i.e. most WP QTLs had limited effects and only a few (13) had major effects (phenotypic variance explained > 15%). The co-locations of QTLs for different WPs as well as QTLs and candidate genes are discussed in terms of phenotypic correlations between traits, and of the function of the candidate genes. The major wood property QTL harbours a gene encoding a Cinnamoyl CoA reductase (CCR), a structural enzyme of the monolignol-specific biosynthesis pathway. Conclusions Given the number of traits analysed, this study provides a comprehensive understanding of the genetic architecture of wood properties in this Eucalyptus full-sib pedigree. At the dawn of Eucalyptus genome sequence, it will provide a framework to identify the nature of genes underlying these important quantitative traits. PMID:21651758
Food activities and identity maintenance in old age: a systematic review and meta-synthesis
Plastow, Nicola Ann; Atwal, Anita; Gilhooly, Mary
2015-01-01
Objectives: Services provided to older people should be developed based on active ageing policies. Nutrition is one aspect of active ageing, but little is known about how food activities contribute to psychological well-being in later life. This is a systematic review of qualitative and quantitative research that answers the question ‘What is known about the relationship between food activities and the maintenance of identities in old age?’. Methods: We followed the preferred reporting items for systematic reviews and meta-analyses guidelines and used quality assessment parameters to complete a systematic review and narrative synthesis. Academic Search Premier, MEDLINE, CINAHL Plus, and PsycINFO databases were searched. Results: We initially identified 8016 articles, of which 167 full-text articles were screened for inclusion. Twenty-two articles were included in the review. There was moderate evidence from nine qualitative and two quantitative studies, of variable quality, that food activities contribute to the maintenance of women's gendered identities, the ethnic identities of men and women, and community identities. There was moderate evidence from 10 qualitative studies, of variable quality, that a change in food choice and deteriorating health changed food activity participation. These changes threatened identities. Most studies included both younger adults and older adults. Conclusion: In later life, there are many life experiences leading to change. Further research is needed to develop understanding of how identity and mental well-being are maintained, despite changes in everyday activities like cooking and eating. This may enable health care professionals to meet psychological needs alongside biological needs during nutritional interventions. PMID:25373998
NASA Astrophysics Data System (ADS)
Yang, Dong-Ping; Robinson, P. A.
2017-04-01
A physiologically based corticothalamic model of large-scale brain activity is used to analyze critical dynamics of transitions from normal arousal states to epileptic seizures, which correspond to Hopf bifurcations. This relates an abstract normal form quantitatively to underlying physiology that includes neural dynamics, axonal propagation, and time delays. Thus, a bridge is constructed that enables normal forms to be used to interpret quantitative data. The normal form of the Hopf bifurcations with delays is derived using Hale's theory, the center manifold theorem, and normal form analysis, and it is found to be explicitly expressed in terms of transfer functions and the sensitivity matrix of a reduced open-loop system. It can be applied to understand the effect of each physiological parameter on the critical dynamics and determine whether the Hopf bifurcation is supercritical or subcritical in instabilities that lead to absence and tonic-clonic seizures. Furthermore, the effects of thalamic and cortical nonlinearities on the bifurcation type are investigated, with implications for the roles of underlying physiology. The theoretical predictions about the bifurcation type and the onset dynamics are confirmed by numerical simulations and provide physiologically based criteria for determining bifurcation types from first principles. The results are consistent with experimental data from previous studies, imply that new regimes of seizure transitions may exist in clinical settings, and provide a simplified basis for control-systems interventions. Using the normal form, and the full equations from which it is derived, more complex dynamics, such as quasiperiodic cycles and saddle cycles, are discovered near the critical points of the subcritical Hopf bifurcations.
Life Prediction Methodologies for Composite Materials
1992-01-31
that is at least a factor of two higher than the neat resin itself. * For tougher epoxies (bis- phenol A, Gic = 270 J/m 2), the two-phase toughening...particles and their blendability with the bis- phenol A resins have also been demonstrated by the researchers. There also appears to be the potential to have...and quantitative understanding of the effects of time on the failure processes, which is especially important for understanding thermoplastic resin and
All biology is computational biology.
Markowetz, Florian
2017-03-01
Here, I argue that computational thinking and techniques are so central to the quest of understanding life that today all biology is computational biology. Computational biology brings order into our understanding of life, it makes biological concepts rigorous and testable, and it provides a reference map that holds together individual insights. The next modern synthesis in biology will be driven by mathematical, statistical, and computational methods being absorbed into mainstream biological training, turning biology into a quantitative science.
NASA Astrophysics Data System (ADS)
Badica, P.; Awaji, S.; Oguro, H.; Nishijima, G.; Watanabe, K.
2006-04-01
Six Nb3Sn composite wires with different architectures ('central and near-the-edge reinforcement') were repeatedly in-plane bent at room temperature (in-plane 'pre-bending'). Breakage behaviour was revealed from scanning electron microscopy observations by semi-quantitative analysis of the filament crack formation and evolution. Cracks are formed in the transversal and longitudinal directions. Transversal cracks show some tolerance to the applied bending strain due to the fact that filaments are composite materials; residual Nb core can arrest development of a partial transversal crack initiated in the Nb3Sn outer part of the filament. Together with the density of cracks C and the evolution of this parameter with pre-bending strain, ɛpb, in different regions of the wire, R-ɛpb curves are important to understand breakage behaviour of the wires. R is the ratio (number of full transversal cracks)/(number of full transversal cracks + number of partial transversal cracks). Parameters C and R allow us to reveal and satisfactorily understand the wire architecture—breakage—critical current decay relationship when pre-bending treatment is applied. As a consequence, breakage criteria necessary to minimize Ic decay were defined and the positive influence of the reinforcement in preventing breakage was observed. It was also found that, in this regard, more Nb in the CuNb reinforcement, for the investigated wires, is better, if the heat treatment for the wire synthesis is performed at 670 °C for 96 h. A different heat treatment, 650 °C for 240 h, is less efficient in preventing filament breakage. Our results suggest the possibility of control and improvement of the breakage susceptibility of the filaments in the wires and, hence, of the bending Ic decay, through the wise design of the wire architecture (i.e. by correlating design with the choice of composing materials and heat treatments).
Health effects of exposure to second- and third-hand marijuana smoke: a systematic review
Holitzki, Hannah; Dowsett, Laura E.; Spackman, Eldon; Noseworthy, Tom; Clement, Fiona
2017-01-01
Background: Recreational marijuana has been legalized in 11 jurisdictions; Canada will legalize marijuana by July 2018. With this changing landscape, there is a need to understand the public health risks associated with marijuana to support patient-care provider conversations, harm-reduction measures and evidence-informed policy. The objective of this work was to summarize the health effects of exposure to second- and third-hand marijuana smoke. Methods: In this systematic review, we searched 6 databases from inception to October 2017. Abstract and full-text review was conducted in duplicate. Studies were included if they were human, in vivo or in vitro studies with more than 1 case reported in English or French, and reported original, quantitative data. Three outcomes were extracted: 1) cannabinoids and cannabinoid metabolites in bodily fluids, 2) self-reported psychoactive effects and 3) eye irritation and discomfort. Results: Of the 1701 abstracts identified, 60 proceeded to full-text review; the final data set contained 15 articles. All of the included studies were of good to poor quality as assessed with the Downs and Black checklist. There is evidence of a direct relation between the tetrahydrocannabinol content of marijuana and effects on those passively exposed. This relation is mediated by several environmental factors including the amount of smoke, ventilation, air volume, number of marijuana cigarettes lit and number of smokers present. No evidence was identified assessing exposure to third-hand marijuana smoke or the health effects of long-term exposure. Interpretation: Exposure to second-hand marijuana smoke leads to cannabinoid metabolites in bodily fluids, and people experience psychoactive effects after such exposure. Alignment of tobacco and marijuana smoking bylaws may result in the most effective public policies. More research is required to understand the impact of exposure to third-hand smoke and the health effects of long-term exposure to second-hand smoke. PMID:29192095
Health effects of exposure to second- and third-hand marijuana smoke: a systematic review.
Holitzki, Hannah; Dowsett, Laura E; Spackman, Eldon; Noseworthy, Tom; Clement, Fiona
2017-11-24
Recreational marijuana has been legalized in 11 jurisdictions; Canada will legalize marijuana by July 2018. With this changing landscape, there is a need to understand the public health risks associated with marijuana to support patient-care provider conversations, harm-reduction measures and evidence-informed policy. The objective of this work was to summarize the health effects of exposure to second- and third-hand marijuana smoke. In this systematic review, we searched 6 databases from inception to October 2017. Abstract and full-text review was conducted in duplicate. Studies were included if they were human, in vivo or in vitro studies with more than 1 case reported in English or French, and reported original, quantitative data. Three outcomes were extracted: 1) cannabinoids and cannabinoid metabolites in bodily fluids, 2) self-reported psychoactive effects and 3) eye irritation and discomfort. Of the 1701 abstracts identified, 60 proceeded to full-text review; the final data set contained 15 articles. All of the included studies were of good to poor quality as assessed with the Downs and Black checklist. There is evidence of a direct relation between the tetrahydrocannabinol content of marijuana and effects on those passively exposed. This relation is mediated by several environmental factors including the amount of smoke, ventilation, air volume, number of marijuana cigarettes lit and number of smokers present. No evidence was identified assessing exposure to third-hand marijuana smoke or the health effects of long-term exposure. Exposure to second-hand marijuana smoke leads to cannabinoid metabolites in bodily fluids, and people experience psychoactive effects after such exposure. Alignment of tobacco and marijuana smoking bylaws may result in the most effective public policies. More research is required to understand the impact of exposure to third-hand smoke and the health effects of long-term exposure to second-hand smoke. Copyright 2017, Joule Inc. or its licensors.
NASA Technical Reports Server (NTRS)
Kierein-Young, K. S.; Kruse, F. A.; Lefkoff, A. B.
1992-01-01
The Jet Propulsion Laboratory Airborne Synthetic Aperture Radar (JPL-AIRSAR) is used to collect full polarimetric measurements at P-, L-, and C-bands. These data are analyzed using the radar analysis and visualization environment (RAVEN). The AIRSAR data are calibrated using in-scene corner reflectors to allow for quantitative analysis of the radar backscatter. RAVEN is used to extract surface characteristics. Inversion models are used to calculate quantitative surface roughness values and fractal dimensions. These values are used to generate synthetic surface plots that represent the small-scale surface structure of areas in Death Valley. These procedures are applied to a playa, smooth salt-pan, and alluvial fan surfaces in Death Valley. Field measurements of surface roughness are used to verify the accuracy.
Quantitative three-dimensional photoacoustic tomography of the finger joints: an in vivo study
NASA Astrophysics Data System (ADS)
Sun, Yao; Sobel, Eric; Jiang, Huabei
2009-11-01
We present for the first time in vivo full three-dimensional (3-D) photoacoustic tomography (PAT) of the distal interphalangeal joint in a human subject. Both absorbed energy density and absorption coefficient images of the joint are quantitatively obtained using our finite-element-based photoacoustic image reconstruction algorithm coupled with the photon diffusion equation. The results show that major anatomical features in the joint along with the side arteries can be imaged with a 1-MHz transducer in a spherical scanning geometry. In addition, the cartilages associated with the joint can be quantitatively differentiated from the phalanx. This in vivo study suggests that the 3-D PAT method described has the potential to be used for early diagnosis of joint diseases such as osteoarthritis and rheumatoid arthritis.