Thermal x-ray diffraction and near-field phase contrast imaging

NASA Astrophysics Data System (ADS)

Li, Zheng; Classen, Anton; Peng, Tao; Medvedev, Nikita; Wang, Fenglin; Chapman, Henry N.; Shih, Yanhua

2017-10-01

Using higher-order coherence of thermal light sources, the resolution power of standard x-ray imaging techniques can be enhanced. In this work, we applied the higher-order measurement to far-field x-ray diffraction and near-field phase contrast imaging (PCI), in order to achieve superresolution in x-ray diffraction and obtain enhanced intensity contrast in PCI. The cost of implementing such schemes is minimal compared to the methods that achieve similar effects by using entangled x-ray photon pairs.

Thermal x-ray diffraction and near-field phase contrast imaging

DOE PAGES

Li, Zheng; Classen, Anton; Peng, Tao; ...

2017-12-27

Using higher-order coherence of thermal light sources, the resolution power of standard x-ray imaging techniques can be enhanced. Here in this work, we applied the higher-order measurement to far-field x-ray diffraction and near-field phase contrast imaging (PCI), in order to achieve superresolution in x-ray diffraction and obtain enhanced intensity contrast in PCI. The cost of implementing such schemes is minimal compared to the methods that achieve similar effects by using entangled x-ray photon pairs.

Factors Influencing Achievement in Undergraduate Social Science Research Methods Courses: A Mixed Methods Analysis

ERIC Educational Resources Information Center

Markle, Gail

2017-01-01

Undergraduate social science research methods courses tend to have higher than average rates of failure and withdrawal. Lack of success in these courses impedes students' progression through their degree programs and negatively impacts institutional retention and graduation rates. Grounded in adult learning theory, this mixed methods study…

Evoked prior learning experience and approach to learning as predictors of academic achievement.

PubMed

Trigwell, Keith; Ashwin, Paul; Millan, Elena S

2013-09-01

In separate studies and research from different perspectives, five factors are found to be among those related to higher quality outcomes of student learning (academic achievement). Those factors are higher self-efficacy, deeper approaches to learning, higher quality teaching, students' perceptions that their workload is appropriate, and greater learning motivation. University learning improvement strategies have been built on these research results. To investigate how students' evoked prior experience, perceptions of their learning environment, and their approaches to learning collectively contribute to academic achievement. This is the first study to investigate motivation and self-efficacy in the same educational context as conceptions of learning, approaches to learning and perceptions of the learning environment. Undergraduate students (773) from the full range of disciplines were part of a group of over 2,300 students who volunteered to complete a survey of their learning experience. On completing their degrees 6 and 18 months later, their academic achievement was matched with their learning experience survey data. A 77-item questionnaire was used to gather students' self-report of their evoked prior experience (self-efficacy, learning motivation, and conceptions of learning), perceptions of learning context (teaching quality and appropriate workload), and approaches to learning (deep and surface). Academic achievement was measured using the English honours degree classification system. Analyses were conducted using correlational and multi-variable (structural equation modelling) methods. The results from the correlation methods confirmed those found in numerous earlier studies. The results from the multi-variable analyses indicated that surface approach to learning was the strongest predictor of academic achievement, with self-efficacy and motivation also found to be directly related. In contrast to the correlation results, a deep approach to learning was not related to academic achievement, and teaching quality and conceptions of learning were only indirectly related to achievement. Research aimed at understanding how students experience their learning environment and how that experience relates to the quality of their learning needs to be conducted using a wider range of variables and more sophisticated analytical methods. In this study of one context, some of the relations found in earlier bivariate studies, and on which learning intervention strategies have been built, are not confirmed when more holistic teaching-learning contexts are analysed using multi-variable methods. © 2012 The British Psychological Society.

Strategies for Increasing Academic Achievement in Higher Education

ERIC Educational Resources Information Center

Ensign, Julene; Woods, Amelia Mays

2014-01-01

Higher education today faces unique challenges. Decreasing student engagement, increasing diversity, and limited resources all contribute to the issues being faced by students, educators, and administrators alike. The unique characteristics and expectations that students bring to their professional programs require new methods of addressing…

Some methods for achieving more efficient performance of fuel assemblies

NASA Astrophysics Data System (ADS)

Boltenko, E. A.

2014-07-01

More efficient operation of reactor plant fuel assemblies can be achieved through the use of new technical solutions aimed at obtaining more uniform distribution of coolant over the fuel assembly section, more intense heat removal on convex heat-transfer surfaces, and higher values of departure from nucleate boiling ratio (DNBR). Technical solutions using which it is possible to obtain more intense heat removal on convex heat-transfer surfaces and higher DNBR values in reactor plant fuel assemblies are considered. An alternative heat removal arrangement is described using which it is possible to obtain a significantly higher power density in a reactor plant and essentially lower maximal fuel rod temperature.

Systemic Synthesis Questions [SSynQs] as Tools to Help Students to Build Their Cognitive Structures in a Systemic Manner

NASA Astrophysics Data System (ADS)

Hrin, Tamara N.; Fahmy, Ameen F. M.; Segedinac, Mirjana D.; Milenković, Dušica D.

2016-08-01

Many studies dedicated to the teaching and learning of organic chemistry courses have emphasized that high school students have shown significant difficulties in mastering the concepts of this discipline. Therefore, the aim of our study was to help students to overcome these difficulties by applying systemic synthesis questions, [SSynQs], as the instructional method in our intervention. This work shows that students from the group exposed to the new teaching method achieved higher scores on final testing than students from the control group, who were taught by the traditional method, when students' achievements in conventional, linear questions [LQs] and in [SSynQs] were studied. These results were followed by observation of lower levels of mental effort by students from the intervention group, and higher levels of mental effort in the control group, invested during solving both types of questions. This correlation between achievement and mental effort resulted in high instructional efficiency for the applied method in the intervention group, [SSynQs], and low instructional efficiency for the traditional teaching and learning method applied in the control group. A systemic triangular relation between achievement, mental effort, and instructional efficiency, established by each group and gender, emphasized that the application of [SSynQs] was more suited to female students than for male students because of [SSynQs] characteristics as teaching and learning tools and because of learning style and ability differences between genders.

Privacy Protection by Matrix Transformation

NASA Astrophysics Data System (ADS)

Yang, Weijia

Privacy preserving is indispensable in data mining. In this paper, we present a novel clustering method for distributed multi-party data sets using orthogonal transformation and data randomization techniques. Our method can not only protect privacy in face of collusion, but also achieve a higher level of accuracy compared to the existing methods.

A Comparison of Computer-Assisted Instruction and Tutorials in Hematology and Oncology.

ERIC Educational Resources Information Center

Garrett, T. J.; And Others

1987-01-01

A study comparing the effectiveness of computer-assisted instruction (CAI) and small group instruction found no significant difference in medical student achievement in oncology but higher achievement through small-group instruction in hematology. Students did not view CAI as more effective, but saw it as a supplement to traditional methods. (MSE)

Humanities & Arts to the Rescue of Science

ERIC Educational Resources Information Center

Papacosta, Pangratios

2007-01-01

The future of science may depend on how education responds to the growing negativism that students and the public show towards science. What is the value of our current teaching methods, if in helping students achieve higher test scores, they also generate a lifelong disdain of science? Achieving a positive attitude towards science must become a…

Changes in higher order aberrations after wavefront-guided PRK for correction of low to moderate myopia and myopic astigmatism: two-year follow-up.

PubMed

Wigledowska-Promienska, D; Zawojska, I

2007-01-01

To assess efficacy, safety, and changes in higher order aberrations after wavefront-guided photorefractive keratectomy (PRK) in comparison with conventional PRK for low to moderate myopia with myopic astigmatism using a WASCA Workstation with the MEL 70 G-Scan excimer laser. A total of 126 myopic or myopic-astigmatic eyes of 112 patients were included in this retrospective study. Patients were divided into two groups: Group 1, the study group; and Group 2, the control group. Group 1 consisted of 78 eyes treated with wavefront-guided PRK. Group 2 consisted of 48 eyes treated with spherocylindrical conventional PRK. Two years postoperatively, in Group 1, 5% of eyes achieved an uncorrected visual acuity (UCVA) of 0.05; 69% achieved a UCVA of 0.00; 18% of eyes experienced enhanced visual acuity of -0.18 and 8% of -0.30. In Group 2, 8% of eyes achieved a UCVA of 0.1; 25% achieved a UCVA of 0.05; and 67% achieved a UCVA of 0.00 according to logMAR calculation method. Total higher-order root-mean square increased by a factor 1.18 for Group 1 and 1.6 for Group 2. There was a significant increase of coma by a factor 1.74 in Group 2 and spherical aberration by a factor 2.09 in Group 1 and 3.56 in Group 2. The data support the safety and effectiveness of the wavefront-guided PRK using a WASCA Workstation for correction of low to moderate refractive errors. This method reduced the number of higher order aberrations induced by excimer laser surgery and improved uncorrected and spectacle-corrected visual acuity when compared to conventional PRK.

Leadership, self-efficacy, and student achievement

NASA Astrophysics Data System (ADS)

Grayson, Kristin

This study examined the relationships between teacher leadership, science teacher self-efficacy, and fifth-grade science student achievement in diverse schools in a San Antonio, Texas, metropolitan school district. Teachers completed a modified version of the Leadership Behavior Description Question (LBDQ) Form XII by Stogdill (1969), the Science Efficacy and Belief Expectations for Science Teaching (SEBEST) by Ritter, Boone, and Rubba (2001, January). Students' scores on the Texas Assessment of Knowledge and Skills (TAKS) measured fifth-grade science achievement. At the teacher level of analysis multiple regressions showed the following relationships between teachers' science self-efficacy and teacher classroom leadership behaviors and the various teacher and school demographic variables. Predictors of teacher self efficacy beliefs included teacher's level of education, gender, and leadership initiating structure. The only significant predictor of teacher self-efficacy outcome expectancy was gender. Higher teacher self-efficacy beliefs predicted higher leadership initiating structure. At the school level of analysis, higher school levels of percentage of students from low socio-economic backgrounds and higher percentage of limited English proficient students predicted lower school student mean science achievement. These findings suggest a need for continued research to clarify relationships between teacher classroom leadership, science teacher self-efficacy, and student achievement especially at the teacher level of analysis. Findings also indicate the importance of developing instructional methods to address student demographics and their needs so that all students, despite their backgrounds, will achieve in science.

What is the Effect of Case-Based Learning on the Academic Achievement of Students on the Topic of "Biochemical Oxygen Demand?"

NASA Astrophysics Data System (ADS)

Günter, Tuğçe; Alpat, Sibel Kılınç

2017-11-01

The purpose of this study was to investigate the effect of the case-based learning (CBL) method used in "biochemical oxygen demand (BOD)," which is a topic taught in the environmental chemistry course, at Dokuz Eylul University, on the academic achievement and opinions of students. The research had a quasi-experimental design and the study group consisted of 4th and 5th grade students (N = 18) attending the Chemistry Teaching Program in a university in Izmir. The "Biochemical Oxygen Demand Achievement Test (BODAT)" and the structured interview form were used as data collection tools. The results of BODAT post-test showed the higher increase in the achievement scores of the experimental group may be an indication of the effectiveness of the CBL method in improving academic achievement in the relevant topic. In addition, the experimental and control group students had positive opinions regarding the method, the scenario, and the material. The students found the method, the scenario, and the material to be interesting, understandable/instructional, relatable with everyday life, suitable for the topic, and enhancing active participation.

HEAT TRANSFER METHOD

DOEpatents

Gambill, W.R.; Greene, N.D.

1960-08-30

A method is given for increasing burn-out heat fluxes under nucleate boiling conditions in heat exchanger tubes without incurring an increase in pumping power requirements. This increase is achieved by utilizing a spinning flow having a rotational velocity sufficient to produce a centrifugal acceleration of at least 10,000 g at the tube wall. At this acceleration the heat-transfer rate at burn out is nearly twice the rate which can be achieved in a similar tube utilizing axial flow at the same pumping power. At higher accelerations the improvement over axial flow is greater, and heat fluxes in excess of 50 x 10/sup 6/ Btu/hr/sq ft can be achieved.

An Examination of Reading and Mathematic Achievement among Second Grade Students Who Have Received Instruction from Either Teachers Who Have Been Trained in Choice Theory/Reality Therapy Methods or Teachers Who Have Not Been Trained

ERIC Educational Resources Information Center

Hale, Jane V.

2011-01-01

The purpose of this study was to see if second grade students who were taught by teachers trained in choice theory/reality therapy (CT/RT) methods had higher achievement scores in mathematics/reading compared to students who were taught by teachers who were not trained. The American School Counselor Association (ASCA) National Model suggests that…

You Gotta Be Determined to Get in There: Voices of Women Higher Education Technology Leaders

ERIC Educational Resources Information Center

Drury, Marilyn

2010-01-01

Three women higher education Chief Information Officers (CIOs) provided their lived experiences and perspectives on barriers they encountered and methods used to overcome the barriers as they pursued and achieved their current positions. The conceptual framework intersects gendered organizational theory, feminist standpoint theory, and…

An Analysis of the Effect of Mobile Learning on Lebanese Higher Education

ERIC Educational Resources Information Center

Jabbour, Khayrazad Kari

2014-01-01

This research explores the effect of mobile technology in Lebanese higher education classrooms. Three components were utilized to evaluate the impact: student attitudes, student achievements, and educational process. This study used both quantitative and qualitative methods to examine the research questions. The main sources for data collection…

Two-photon or higher-order absorbing optical materials and methods of use

NASA Technical Reports Server (NTRS)

Marder, Seth (Inventor); Perry, Joseph (Inventor)

2012-01-01

Compositions capable of simultaneous two-photon absorption and higher order absorptivities are provided. Compounds having a donor-pi-donor or acceptor-pi-acceptor structure are of particular interest, where the donor is an electron donating group, acceptor is an electron accepting group, and pi is a pi bridge linking the donor and/or acceptor groups. The pi bridge may additionally be substituted with electron donating or withdrawing groups to alter the absorptive wavelength of the structure. Also disclosed are methods of generating an excited state of such compounds through optical stimulation with light using simultaneous absorption of photons of energies individually insufficient to achieve an excited state of the compound, but capable of doing so upon simultaneous absorption of two or more such photons. Applications employing such methods are also provided, including controlled polymerization achieved through focusing of the light source(s) used.

Dual Temporal Scale Convolutional Neural Network for Micro-Expression Recognition.

PubMed

Peng, Min; Wang, Chongyang; Chen, Tong; Liu, Guangyuan; Fu, Xiaolan

2017-01-01

Facial micro-expression is a brief involuntary facial movement and can reveal the genuine emotion that people try to conceal. Traditional methods of spontaneous micro-expression recognition rely excessively on sophisticated hand-crafted feature design and the recognition rate is not high enough for its practical application. In this paper, we proposed a Dual Temporal Scale Convolutional Neural Network (DTSCNN) for spontaneous micro-expressions recognition. The DTSCNN is a two-stream network. Different of stream of DTSCNN is used to adapt to different frame rate of micro-expression video clips. Each stream of DSTCNN consists of independent shallow network for avoiding the overfitting problem. Meanwhile, we fed the networks with optical-flow sequences to ensure that the shallow networks can further acquire higher-level features. Experimental results on spontaneous micro-expression databases (CASME I/II) showed that our method can achieve a recognition rate almost 10% higher than what some state-of-the-art method can achieve.

Covariate Measurement Error Correction for Student Growth Percentiles Using the SIMEX Method

ERIC Educational Resources Information Center

Shang, Yi; VanIwaarden, Adam; Betebenner, Damian W.

2015-01-01

In this study, we examined the impact of covariate measurement error (ME) on the estimation of quantile regression and student growth percentiles (SGPs), and find that SGPs tend to be overestimated among students with higher prior achievement and underestimated among those with lower prior achievement, a problem we describe as ME endogeneity in…

Alternative Methods for Estimating Achievement Trends and School Effects: When Is Simple Good Enough?

ERIC Educational Resources Information Center

Warkentien, Siri; Silver, David

2016-01-01

Public schools with impressive records of serving lower-performing students are often overlooked because their average test scores, even when students are growing quickly, are lower than scores in schools that serve higher-performing students. Schools may appear to be doing poorly either because baseline achievement is not easily accounted for or…

Personality, Motivation, and Math Achievement Among Turkish Students.

PubMed

Akben-Selcuk, Elif

2017-04-01

Using the Turkish portion of the Programme for International Student Assessment dataset ( N = 4,848; 51% boys, 49% girls; age, M = 15.81 years, SD = 0.28), this study investigated factors associated with mathematics achievement among Turkish students. Three different models were estimated using the method of balanced repeated replication with Fay's method and taking into account the presence of five plausible values of the dependent variable. Results showed that male students and older students had better mathematics proficiency. Socio-economic status and school resources also played a significant role in explaining student achievement in mathematics. Finally, students who were more open to problem solving, who attributed their failure to external factors, and who were intrinsically motivated to learn mathematics achieved higher scores. Policy implications are provided.

Mentoring Women and Minorities in Higher Education.

ERIC Educational Resources Information Center

Cordova, Fred; And Others

Some relevant issues concerning the mentoring of women and minorities in the realm of higher education are addressed, primarily focusing on the differences and problems that exist in assisting these two groups of professionals in achieving their career goals. The importance of mentoring and methods that can be used by a mentor in assisting the…

Chinese International Undergraduate Students at a U.S. University: A Mixed Methods Study of First-Year Academic Experiences and Achievement

ERIC Educational Resources Information Center

Ma, Wei

2014-01-01

The purpose of this study was to explore the first-year academic experiences and achievement of Chinese international undergraduate students in American higher education. To do so, I tracked a cohort of Chinese international undergraduates through their first-year at a public research university in the United States. Both qualitative and…

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ranganathan, V; Kumar, P; Bzdusek, K

Purpose: We propose a novel data-driven method to predict the achievability of clinical objectives upfront before invoking the IMRT optimization. Methods: A new metric called “Geometric Complexity (GC)” is used to estimate the achievability of clinical objectives. Here, GC is the measure of the number of “unmodulated” beamlets or rays that intersect the Region-of-interest (ROI) and the target volume. We first compute the geometric complexity ratio (GCratio) between the GC of a ROI (say, parotid) in a reference plan and the GC of the same ROI in a given plan. The GCratio of a ROI indicates the relative geometric complexitymore » of the ROI as compared to the same ROI in the reference plan. Hence GCratio can be used to predict if a defined clinical objective associated with the ROI can be met by the optimizer for a given case. Basically a higher GCratio indicates a lesser likelihood for the optimizer to achieve the clinical objective defined for a given ROI. Similarly, a lower GCratio indicates a higher likelihood for the optimizer to achieve the clinical objective defined for the given ROI. We have evaluated the proposed method on four Head and Neck cases using Pinnacle3 (version 9.10.0) Treatment Planning System (TPS). Results: Out of the total of 28 clinical objectives from four head and neck cases included in the study, 25 were in agreement with the prediction, which implies an agreement of about 85% between predicted and obtained results. The Pearson correlation test shows a positive correlation between predicted and obtained results (Correlation = 0.82, r2 = 0.64, p < 0.005). Conclusion: The study demonstrates the feasibility of the proposed method in head and neck cases for predicting the achievability of clinical objectives with reasonable accuracy.« less

The relationship between physical fitness and academic achievement among adolescent in South Korea.

PubMed

Han, Gun-Soo

2018-04-01

[Purpose] The purpose of this study was to identify the relationship between physical fitness level and academic achievement in middle school students. [Subjects and Methods] A total of 236 students aged 13-15 from three middle schools in D city, South Korea, were selected using a random sampling method. Academic achievement was measured by students' 2014 fall-semester final exam scores and the level of physical fitness was determined according to the PAPS (Physical Activity Promotion System) score administrated by the Korean Ministry of Education. A Pearson correlation test with SPSS 20.0 was employed. [Results] The Pearson correlation test revealed a significant correlation between physical fitness and academic achievement. Specifically, students with higher levels of physical fitness tend to have higher academic performance. In addition, final exam scores of core subjects (e.g., English, mathematics, and science) were significantly related to the PAPS score. [Conclusion] Results of this study can be used to develop more effective physical education curricula. In addition, the data can also be applied to recreation and sport programs for other populations (e.g., children and adult) as well as existing national physical fitness data in various countries.

Autonomous Control of Nuclear Power Plants

DOE Office of Scientific and Technical Information (OSTI.GOV)

Basher, H.

2003-10-20

A nuclear reactor is a complex system that requires highly sophisticated controllers to ensure that desired performance and safety can be achieved and maintained during its operations. Higher-demanding operational requirements such as reliability, lower environmental impacts, and improved performance under adverse conditions in nuclear power plants, coupled with the complexity and uncertainty of the models, necessitate the use of an increased level of autonomy in the control methods. In the opinion of many researchers, the tasks involved during nuclear reactor design and operation (e.g., design optimization, transient diagnosis, and core reload optimization) involve important human cognition and decisions that maymore » be more easily achieved with intelligent methods such as expert systems, fuzzy logic, neural networks, and genetic algorithms. Many experts in the field of control systems share the idea that a higher degree of autonomy in control of complex systems such as nuclear plants is more easily achievable through the integration of conventional control systems and the intelligent components. Researchers have investigated the feasibility of the integration of fuzzy logic, neural networks, genetic algorithms, and expert systems with the conventional control methods to achieve higher degrees of autonomy in different aspects of reactor operations such as reactor startup, shutdown in emergency situations, fault detection and diagnosis, nuclear reactor alarm processing and diagnosis, and reactor load-following operations, to name a few. With the advancement of new technologies and computing power, it is feasible to automate most of the nuclear reactor control and operation, which will result in increased safety and economical benefits. This study surveys current status, practices, and recent advances made towards developing autonomous control systems for nuclear reactors.« less

Chapter 10 Human Oocyte Vitrification.

PubMed

Rienzi, Laura; Cobo, Ana; Ubaldi, Filippo Maria

2017-01-01

Discovery and widespread application of successful cryopreservation methods for MII-phase oocytes was one of the greatest successes in human reproduction during the past decade. Although considerable improvements in traditional slow-rate freezing were also achieved, the real breakthrough was the result of introduction of vitrification. Here we describe the method that is most commonly applied for this purpose, provides consistent survival and in vitro developmental rates, results in pregnancy and birth rates comparable to those achievable with fresh oocytes, and does not result in higher incidence of gynecological or postnatal complications.

Multiple intelligences and alternative teaching strategies: The effects on student academic achievement, conceptual understanding, and attitude

NASA Astrophysics Data System (ADS)

Baragona, Michelle

The purpose of this study was to investigate the interactions between multiple intelligence strengths and alternative teaching methods on student academic achievement, conceptual understanding and attitudes. The design was a quasi-experimental study, in which students enrolled in Principles of Anatomy and Physiology, a developmental biology course, received lecture only, problem-based learning with lecture, or peer teaching with lecture. These students completed the Multiple Intelligence Inventory to determine their intelligence strengths, the Students' Motivation Toward Science Learning questionnaire to determine student attitudes towards learning in science, multiple choice tests to determine academic achievement, and open-ended questions to determine conceptual understanding. Effects of intelligence types and teaching methods on academic achievement and conceptual understanding were determined statistically by repeated measures ANOVAs. No significance occurred in academic achievement scores due to lab group or due to teaching method used; however, significant interactions between group and teaching method did occur in students with strengths in logical-mathematical, interpersonal, kinesthetic, and intrapersonal intelligences. Post-hoc analysis using Tukey HSD tests revealed students with strengths in logical-mathematical intelligence and enrolled in Group Three scored significantly higher when taught by problem-based learning (PBL) as compared to peer teaching (PT). No significance occurred in conceptual understanding scores due to lab group or due to teaching method used; however, significant interactions between group and teaching method did occur in students with strengths in musical, kinesthetic, intrapersonal, and spatial intelligences. Post-hoc analysis using Tukey HSD tests revealed students with strengths in logical-mathematical intelligence and enrolled in Group Three scored significantly higher when taught by lecture as compared to PBL. Students with strengths in intrapersonal intelligence and enrolled in Group One scored significantly lower when taught by lecture as compared to PBL. Results of a repeated measures ANOVA for student attitudes showed significant increases in positive student attitudes toward science learning for all three types of teaching method between pretest and posttest; but there were no significant differences in posttest attitude scores by type of teaching method.

Using Future Research Methods in Analysing Policies Relating to Open Distance Education in Africa

ERIC Educational Resources Information Center

Makoe, Mpine Elizabeth

2018-01-01

Many African countries have developed policies to reform their education system in order to widen participation in higher education. To achieve this, open, online and distance education based models have been advocated as the most viable delivery tools in expanding access to higher education. However, the policy analysis of Kenya, Rwanda and…

Identifying Factors That Affect Higher Educational Achievements of Jamaican Seventh-Day Adventists

ERIC Educational Resources Information Center

Campbell, Samuel P.

2011-01-01

This mixed-method explanatory research examined factors that influenced Jamaican Seventh-day Adventist (SDA) members to pursue higher education. It sought to investigate whether the source of the motivation is tied to the Church's general philosophy on education or to its overall programs as experienced by the membership at large. The question of…

Community College Students' Assessments of the Costs and Benefits of Borrowing to Finance Higher Education

ERIC Educational Resources Information Center

McKinney, Lyle; Mukherjee, Moumita; Wade, Jerrel; Shefman, Pamelyn; Breed, Rachel

2015-01-01

Objective: The purpose of this study was to understand how community college students assess the risks and rewards of using personal loans to achieve their higher education goals. Method: Interviews were conducted with 12 federal loan borrowers attending a large, urban community college in Texas during the Spring 2013 semester. Results: Findings…

A Model for Using a Capstone Experience as One Method of Assessment of an Information Systems Degree Program

ERIC Educational Resources Information Center

Murray, Meg; Perez, Jorge; Guimaraes, Mario

2008-01-01

Student attainment of educational outcomes is a core purpose of any institution of higher education and assessment provides a vehicle through which a program of study is able to ascertain how well it is achieving its stated learning outcomes and how program improvement might be achieved. Assessment of student learning begins with the clear…

The effects of higher-order questioning strategies on nonscience majors' achievement in an introductory environmental science course and their attitudes toward the environment

NASA Astrophysics Data System (ADS)

Eason, Grace Teresa

The purpose of this quasi-experimental study was to determine the effect a higher-order questioning strategy (Bloom, 1956) had on undergraduate non-science majors' attitudes toward the environment and their achievement in an introductory environmental science course, EDS 1032, "Survey of Science 2: Life Science," which was offered during the Spring 2000 term. Students from both treatment and control groups (N = 63), which were determined using intact classes, participated in eight cooperative group activities based on the Biological Sciences Curriculum Studies (BSCS) 5E model (Bybee, 1993). The treatment group received a higher-order questioning method combined with the BSCS 5E model. The control group received a lower-order questioning method, combined with the BSCS 5E model. Two instruments were used to measure students' attitude and achievement changes. The Ecology Issue Attitude (EIA) survey (Schindler, 1995) and a comprehensive environmental science final exam. Kolb's Learning Style Inventory (KLSI, 1985) was used to measure students' learning style type. After a 15-week treatment period, results were analyzed using MANCOVA. The overall MANCOVA model used to test the statistical difference between the collective influences of the independent variables on the three dependent variables simultaneously was found to be not significant at alpha = .05. This differs from findings of previous studies in which higher-order questioning techniques had a significant effect on student achievement (King 1989 & 1992; Blosser, 1991; Redfield and Rousseau, 1981; Gall 1970). At the risk of inflated Type I and Type II error rates, separate univariate analyses were performed. However, none of the research factors, when examined collectively or separately, made any significant contribution to explaining the variability in EIA attitude, EIA achievement, and comprehensive environmental science final examination scores. Nevertheless, anecdotal evidence from student's self-reported behavior changes indicated favorable responses to an increased awareness of and positive action toward the environment.

A fast isogeometric BEM for the three dimensional Laplace- and Helmholtz problems

NASA Astrophysics Data System (ADS)

Dölz, Jürgen; Harbrecht, Helmut; Kurz, Stefan; Schöps, Sebastian; Wolf, Felix

2018-03-01

We present an indirect higher order boundary element method utilising NURBS mappings for exact geometry representation and an interpolation-based fast multipole method for compression and reduction of computational complexity, to counteract the problems arising due to the dense matrices produced by boundary element methods. By solving Laplace and Helmholtz problems via a single layer approach we show, through a series of numerical examples suitable for easy comparison with other numerical schemes, that one can indeed achieve extremely high rates of convergence of the pointwise potential through the utilisation of higher order B-spline-based ansatz functions.

The influence of contextual teaching with the problem solving method on students' knowledge and attitudes toward horticulture, science, and school

NASA Astrophysics Data System (ADS)

Whitcher, Carrie Lynn

2005-08-01

Adolescence is marked with many changes in the development of higher order thinking skills. As students enter high school they are expected to utilize these skills to solve problems, become abstract thinkers, and contribute to society. The goal of this study was to assess horticultural science knowledge achievement and attitude toward horticulture, science, and school in high school agriculture students. There were approximately 240 high school students in the sample including both experimental and control groups from California and Washington. Students in the experimental group participated in an educational program called "Hands-On Hortscience" which emphasized problem solving in investigation and experimentation activities with greenhouse plants, soilless media, and fertilizers. Students in the control group were taught by the subject matter method. The activities included in the Hands-On Hortscience curriculum were created to reinforce teaching the scientific method through the context of horticulture. The objectives included evaluating whether the students participating in the Hands-On Hortscience experimental group benefited in the areas of science literacy, data acquisition and analysis, and attitude toward horticulture, science, and school. Pre-tests were administered in both the experimental and control groups prior to the research activities and post-tests were administered after completion. The survey questionnaire included a biographical section and attitude survey. Significant increases in hortscience achievement were found from pre-test to post-test in both control and experimental study groups. The experimental treatment group had statistically higher achievement scores than the control group in the two areas tested: scientific method (p=0.0016) and horticulture plant nutrition (p=0.0004). In addition, the students participating in the Hands-On Hortscience activities had more positive attitudes toward horticulture, science, and school (p=0.0033). Students who were more actively involved in hands-on projects had higher attitude scores compared to students who were taught traditional methods alone. In demographic comparisons, females had more positive attitudes toward horticulture science than males; and students from varying ethnic backgrounds had statistically different achievement (p=0.0001). Ethnicity was determined with few students in each background, 8 in one ethnicity and 10 students in another. Youth organization membership such as FFA or 4-H had no significant bearing on achievement or attitude.

Dual Temporal Scale Convolutional Neural Network for Micro-Expression Recognition

PubMed Central

Peng, Min; Wang, Chongyang; Chen, Tong; Liu, Guangyuan; Fu, Xiaolan

2017-01-01

Facial micro-expression is a brief involuntary facial movement and can reveal the genuine emotion that people try to conceal. Traditional methods of spontaneous micro-expression recognition rely excessively on sophisticated hand-crafted feature design and the recognition rate is not high enough for its practical application. In this paper, we proposed a Dual Temporal Scale Convolutional Neural Network (DTSCNN) for spontaneous micro-expressions recognition. The DTSCNN is a two-stream network. Different of stream of DTSCNN is used to adapt to different frame rate of micro-expression video clips. Each stream of DSTCNN consists of independent shallow network for avoiding the overfitting problem. Meanwhile, we fed the networks with optical-flow sequences to ensure that the shallow networks can further acquire higher-level features. Experimental results on spontaneous micro-expression databases (CASME I/II) showed that our method can achieve a recognition rate almost 10% higher than what some state-of-the-art method can achieve. PMID:29081753

Programmed Instruction in Secondary Education: A Meta-Analysis of the Impact of Class Size on Its Effectiveness.

ERIC Educational Resources Information Center

Boden, Andrea; Archwamety, Teara; McFarland, Max

This review used meta-analytic techniques to integrate findings from 30 independent studies that compared programmed instruction to conventional methods of instruction at the secondary level. The meta-analysis demonstrated that programmed instruction resulted in higher achievement when compared to conventional methods of instruction (average…

The Effect of Cooperative Learning: University Example

ERIC Educational Resources Information Center

Tombak, Busra; Altun, Sertel

2016-01-01

Problem Statement: Motivation is a significant component of success in education, and it is best achieved by constructivist learning methods, especially cooperative Learning (CL). CL is a popular method among primary and secondary schools, but it is rarely used in higher education due to the large numbers of students and time restrictions. The…

Enhanced speed in fluorescence imaging using beat frequency multiplexing

NASA Astrophysics Data System (ADS)

Mikami, Hideharu; Kobayashi, Hirofumi; Wang, Yisen; Hamad, Syed; Ozeki, Yasuyuki; Goda, Keisuke

2016-03-01

Fluorescence imaging using radiofrequency-tagged emission (FIRE) is an emerging technique that enables higher imaging speed (namely, temporal resolution) in fluorescence microscopy compared to conventional fluorescence imaging techniques such as confocal microscopy and wide-field microscopy. It works based on the principle that it uses multiple intensity-modulated fields in an interferometric setup as excitation fields and applies frequency-division multiplexing to fluorescence signals. Unfortunately, despite its high potential, FIRE has limited imaging speed due to two practical limitations: signal bandwidth and signal detection efficiency. The signal bandwidth is limited by that of an acousto-optic deflector (AOD) employed in the setup, which is typically 100-200 MHz for the spectral range of fluorescence excitation (400-600 nm). The signal detection efficiency is limited by poor spatial mode-matching between two interfering fields to produce a modulated excitation field. Here we present a method to overcome these limitations and thus to achieve higher imaging speed than the prior version of FIRE. Our method achieves an increase in signal bandwidth by a factor of two and nearly optimal mode matching, which enables the imaging speed limited by the lifetime of the target fluorophore rather than the imaging system itself. The higher bandwidth and better signal detection efficiency work synergistically because higher bandwidth requires higher signal levels to avoid the contribution of shot noise and amplifier noise to the fluorescence signal. Due to its unprecedentedly high-speed performance, our method has a wide variety of applications in cancer detection, drug discovery, and regenerative medicine.

An Investigation to Determine if Higher Speeds are Obtained with the Diamond Jubilee Gregg Shorthand Method.

ERIC Educational Resources Information Center

Starbuck, Ethel

The purpose of the study was to determine whether higher shorthand speeds were achieved by high school students in a 1-year shorthand course through the use of Simplified Gregg Shorthand or through the use of Diamond Jubilee (DJ) Gregg Shorthand. The control group consisted of 75 students enrolled in Simplified Shorthand during the years…

An Inquiry into Conflict Management Strategies: Study of Higher Education Institutions in Khyber Pakhtunkhwa, Pakistan

ERIC Educational Resources Information Center

Din, Siraj ud; Khan, Bakhtiar; Bibi, Zainab

2012-01-01

The purpose of this paper is to gain an insight into the conflict management strategies (CMS) of faculty in the higher education institutions (HEIs) of Khyber Pakhtunkhwa, Pakistan. To achieve the above mentioned purpose, survey method was used with the help of questionnaire. In this research, impact of CMS was assessed on the negative…

A Mixed Method Study of Factors Associated with the Academic Achievement of Latina/o College Students from Predominantly Mexican American Backgrounds: A Strengths-Based Approach

ERIC Educational Resources Information Center

Lara, Laura G.

2009-01-01

Young adults from Latina/o backgrounds draw from cultural assets and wrestle with distinctive challenges as they enter into, study at, and graduate from institutions of higher education. In this investigation, I examined the perspectives of Latina/o college students with low and high academic achievement, focusing on their upbringing within…

Mapping implicit spectral methods to distributed memory architectures

NASA Technical Reports Server (NTRS)

Overman, Andrea L.; Vanrosendale, John

1991-01-01

Spectral methods were proven invaluable in numerical simulation of PDEs (Partial Differential Equations), but the frequent global communication required raises a fundamental barrier to their use on highly parallel architectures. To explore this issue, a 3-D implicit spectral method was implemented on an Intel hypercube. Utilization of about 50 percent was achieved on a 32 node iPSC/860 hypercube, for a 64 x 64 x 64 Fourier-spectral grid; finer grids yield higher utilizations. Chebyshev-spectral grids are more problematic, since plane-relaxation based multigrid is required. However, by using a semicoarsening multigrid algorithm, and by relaxing all multigrid levels concurrently, relatively high utilizations were also achieved in this harder case.

Spatial Lattice Modulation for MIMO Systems

NASA Astrophysics Data System (ADS)

Choi, Jiwook; Nam, Yunseo; Lee, Namyoon

2018-06-01

This paper proposes spatial lattice modulation (SLM), a spatial modulation method for multipleinput-multiple-output (MIMO) systems. The key idea of SLM is to jointly exploit spatial, in-phase, and quadrature dimensions to modulate information bits into a multi-dimensional signal set that consists oflattice points. One major finding is that SLM achieves a higher spectral efficiency than the existing spatial modulation and spatial multiplexing methods for the MIMO channel under the constraint ofM-ary pulseamplitude-modulation (PAM) input signaling per dimension. In particular, it is shown that when the SLM signal set is constructed by using dense lattices, a significant signal-to-noise-ratio (SNR) gain, i.e., a nominal coding gain, is attainable compared to the existing methods. In addition, closed-form expressions for both the average mutual information and average symbol-vector-error-probability (ASVEP) of generic SLM are derived under Rayleigh-fading environments. To reduce detection complexity, a low-complexity detection method for SLM, which is referred to as lattice sphere decoding, is developed by exploiting lattice theory. Simulation results verify the accuracy of the conducted analysis and demonstrate that the proposed SLM techniques achieve higher average mutual information and lower ASVEP than do existing methods.

Fully non-inductive second harmonic electron cyclotron plasma ramp-up in the QUEST spherical tokamak

NASA Astrophysics Data System (ADS)

Idei, H.; Kariya, T.; Imai, T.; Mishra, K.; Onchi, T.; Watanabe, O.; Zushi, H.; Hanada, K.; Qian, J.; Ejiri, A.; Alam, M. M.; Nakamura, K.; Fujisawa, A.; Nagashima, Y.; Hasegawa, M.; Matsuoka, K.; Fukuyama, A.; Kubo, S.; Shimozuma, T.; Yoshikawa, M.; Sakamoto, M.; Kawasaki, S.; Nakashima, H.; Higashijima, A.; Ide, S.; Maekawa, T.; Takase, Y.; Toi, K.

2017-12-01

Fully non-inductive second (2nd) harmonic electron cyclotron (EC) plasma current ramp-up was demonstrated with a newlly developed 28 GHz system in the QUEST spherical tokamak. A high plasma current of 54 kA was non-inductively ramped up and sustained stably for 0.9 s with a 270 kW 28 GHz wave. A higher plasma current of 66 kA was also non-inductively achieved with a slow ramp-up of the vertical field. We have achieved a significantly higher plasma current than those achieved previously with the 2nd harmonic EC waves. This fully non-inductive 2nd harmonic EC plasma ramp-up method might be useful for future burning plasma devices and fusion reactors, in particular for operations at half magnetic field with the same EC heating equipment.

Improved accuracy for finite element structural analysis via an integrated force method

NASA Technical Reports Server (NTRS)

Patnaik, S. N.; Hopkins, D. A.; Aiello, R. A.; Berke, L.

1992-01-01

A comparative study was carried out to determine the accuracy of finite element analyses based on the stiffness method, a mixed method, and the new integrated force and dual integrated force methods. The numerical results were obtained with the following software: MSC/NASTRAN and ASKA for the stiffness method; an MHOST implementation method for the mixed method; and GIFT for the integrated force methods. The results indicate that on an overall basis, the stiffness and mixed methods present some limitations. The stiffness method generally requires a large number of elements in the model to achieve acceptable accuracy. The MHOST method tends to achieve a higher degree of accuracy for course models than does the stiffness method implemented by MSC/NASTRAN and ASKA. The two integrated force methods, which bestow simultaneous emphasis on stress equilibrium and strain compatibility, yield accurate solutions with fewer elements in a model. The full potential of these new integrated force methods remains largely unexploited, and they hold the promise of spawning new finite element structural analysis tools.

Experimental Validation for Hot Stamping Process by Using Taguchi Method

NASA Astrophysics Data System (ADS)

Fawzi Zamri, Mohd; Lim, Syh Kai; Razlan Yusoff, Ahmad

2016-02-01

Due to the demand for reduction in gas emissions, energy saving and producing safer vehicles has driven the development of Ultra High Strength Steel (UHSS) material. To strengthen UHSS material such as boron steel, it needed to undergo a process of hot stamping for heating at certain temperature and time. In this paper, Taguchi method is applied to determine the appropriate parameter of thickness, heating temperature and heating time to achieve optimum strength of boron steel. The experiment is conducted by using flat square shape of hot stamping tool with tensile dog bone as a blank product. Then, the value of tensile strength and hardness is measured as response. The results showed that the lower thickness, higher heating temperature and heating time give the higher strength and hardness for the final product. In conclusion, boron steel blank are able to achieve up to 1200 MPa tensile strength and 650 HV of hardness.

Lateral resolution improvement in scanning nonlinear dielectric microscopy by measuring super-higher-order nonlinear dielectric constants

NASA Astrophysics Data System (ADS)

Chinone, N.; Yamasue, K.; Hiranaga, Y.; Honda, K.; Cho, Y.

2012-11-01

Scanning nonlinear dielectric microscopy (SNDM) can be used to visualize polarization distributions in ferroelectric materials and dopant profiles in semiconductor devices. Without using a special sharp tip, we achieved an improved lateral resolution in SNDM through the measurement of super-higher-order nonlinearity up to the fourth order. We observed a multidomain single crystal congruent LiTaO3 (CLT) sample, and a cross section of a metal-oxide-semiconductor (MOS) field-effect-transistor (FET). The imaged domain boundaries of the CLT were narrower in the super-higher-order images than in the conventional image. Compared to the conventional method, the super-higher-order method resolved the more detailed structure of the MOSFET.

Using optimal combination of teaching-learning methods (open book assignment and group tutorials) as revision exercises to improve learning outcome in low achievers in biochemistry.

PubMed

Rajappa, Medha; Bobby, Zachariah; Nandeesha, H; Suryapriya, R; Ragul, Anithasri; Yuvaraj, B; Revathy, G; Priyadarssini, M

2016-07-08

Graduate medical students of India are taught Biochemistry by didactic lectures and they hardly get any opportunity to clarify their doubts and reinforce the concepts which they learn in these lectures. We used a combination of teaching-learning (T-L) methods (open book assignment followed by group tutorials) to study their efficacy in improving the learning outcome. About 143 graduate medical students were classified into low (<50%: group 1, n = 23), medium (50-75%: group 2, n = 74), and high (>75%: group 3, n = 46) achievers, based on their internal assessment marks. After the regular teaching module on the topics "Vitamins and Enzymology", all the students attempted an open book assignment without peer consultation. Then all the students participated in group tutorials. The effects on the groups were evaluated by pre and posttests at the end of each phase, with the same set of MCQs. Gain from group tutorials and overall gain was significantly higher in the low achievers, compared to other groups. High and medium achievers obtained more gain from open book assignment, than group tutorials. The overall gain was significantly higher than the gain obtained from open book assignment or group tutorials, in all three groups. All the three groups retained the gain even after 1 week of the exercise. Hence, optimal use of novel T-L methods (open book assignment followed by group tutorials) as revision exercises help in strengthening concepts in Biochemistry in this oft neglected group of low achievers in graduate medical education. © 2016 by The International Union of Biochemistry and Molecular Biology, 44(4):321-325, 2016. © 2016 The International Union of Biochemistry and Molecular Biology.

College Achievement Through Self-Help. A Planning and Guidance Manual For Minority Students.

ERIC Educational Resources Information Center

Nieves, Luis

In this manual for minority students in higher education, advice is provided on the following topics: (1) methods of self personality assessment, including lists, questions, and flow charts; (2) suggestions for budgeting study time in an individual schedule; (3) relaxation techniques to combat anxiety; (4) methods of self-management in cases of…

Investigations on the heat transport capability of a cryogenic oscillating heat pipe and its application in achieving ultra-fast cooling rates for cell vitrification cryopreservation☆

PubMed Central

Han, Xu; Ma, Hongbin; Jiao, Anjun; Critser, John K.

2010-01-01

Theoretically, direct vitrification of cell suspensions with relatively low concentrations (~1 M) of permeating cryoprotective agents (CPA) is suitable for cryopreservation of almost all cell types and can be accomplished by ultra-fast cooling rates that are on the order of 106–7 K/min. However, the methods and devices currently available for cell cryopreservation cannot achieve such high cooling rates. In this study, we constructed a novel cryogenic oscillating heat pipe (COHP) using liquid nitrogen as its working fluid and investigated its heat transport capability to assess its application for achieving ultra-fast cooling rates for cell cryopreservation. The experimental results showed that the apparent heat transfer coefficient of the COHP can reach 2 × 105 W/m2·K, which is two orders of the magnitude higher than traditional heat pipes. Theoretical analyzes showed that the average local heat transfer coefficient in the thin film evaporation region of the COHP can reach 1.2 × 106 W/m2·K, which is approximately 103 times higher than that achievable with standard pool-boiling approaches. Based on these results, a novel device design applying the COHP and microfabrication techniques is proposed and its efficiency for cell vitrification is demonstrated through numerical simulation. The estimated average cooling rates achieved through this approach is 106–7 K/min, which is much faster than the currently available methods and sufficient for achieving vitrification with relatively low concentrations of CPA. PMID:18430413

Investigations on the heat transport capability of a cryogenic oscillating heat pipe and its application in achieving ultra-fast cooling rates for cell vitrification cryopreservation.

PubMed

Han, Xu; Ma, Hongbin; Jiao, Anjun; Critser, John K

2008-06-01

Theoretically, direct vitrification of cell suspensions with relatively low concentrations ( approximately 1 M) of permeating cryoprotective agents (CPA) is suitable for cryopreservation of almost all cell types and can be accomplished by ultra-fast cooling rates that are on the order of 10(6-7) K/min. However, the methods and devices currently available for cell cryopreservation cannot achieve such high cooling rates. In this study, we constructed a novel cryogenic oscillating heat pipe (COHP) using liquid nitrogen as its working fluid and investigated its heat transport capability to assess its application for achieving ultra-fast cooling rates for cell cryopreservation. The experimental results showed that the apparent heat transfer coefficient of the COHP can reach 2 x 10(5) W/m(2).K, which is two orders of the magnitude higher than traditional heat pipes. Theoretical analyzes showed that the average local heat transfer coefficient in the thin film evaporation region of the COHP can reach 1.2 x 10(6) W/m(2).K, which is approximately 10(3) times higher than that achievable with standard pool-boiling approaches. Based on these results, a novel device design applying the COHP and microfabrication techniques is proposed and its efficiency for cell vitrification is demonstrated through numerical simulation. The estimated average cooling rates achieved through this approach is 10(6-7)K/min, which is much faster than the currently available methods and sufficient for achieving vitrification with relatively low concentrations of CPA.

The Classroom Performance System (CPS): Effects on student participation, attendance, and achievement in multicultural anatomy and physiology classes at South Texas College

NASA Astrophysics Data System (ADS)

Termos, Mohamad Hani

2011-12-01

The Classroom Performance System (CPS) is an instructional technology tool that increases student performance and addresses different learning styles. Instructional technologies are used to promote active learning; however, student embarrassment issue in a multicultural setting is not addressed. This study assessed the effect of the CPS on student participation, attendance, and achievement in multicultural college-level anatomy and physiology classes at South Texas College, where the first spoken language is not English. Quantitative method and quasi-experimental design were employed and comparative statistic methods and pre-post tests were used to collect the data. Participants were college students and sections of study were selected by convenient sampling. Participation was 100% during most of the lectures held and participation rate did not strike above 68% in control group. Attendance was significantly higher in CPS sections than the control group as shown by t-tests. Experimental sections had a higher increase in the pre-post test scores and student averages on lecture exams increased at a higher rate as compared to the control group. Therefore, the CPS increased student participation, attendance, and achievement in multicultural anatomy and physiology classes. The CPS can be studied in other settings where the first spoken language is English or in other programs, such as special education programs. Additionally, other variables can be studied and other methodologies can be employed.

The Influence of the Project Method on the Achievement of Young Learners in the Field Science and Social Studies

ERIC Educational Resources Information Center

Prtljaga, Snežana; Veselinov, Danica

2017-01-01

The paper deals with the influence of project work on the achievement of young learners in the area of science and social studies. The presented results are part of a wider study, in which they were interpreted from a different angle. The goal of the wider study was to determine to what extent a higher level of knowledge acquisition in the field…

A flood map based DOI decoding method for block detector: a GATE simulation study.

PubMed

Shi, Han; Du, Dong; Su, Zhihong; Peng, Qiyu

2014-01-01

Positron Emission Tomography (PET) systems using detectors with Depth of Interaction (DOI) capabilities could achieve higher spatial resolution and better image quality than those without DOI. Up till now, most DOI methods developed are not cost-efficient for a whole body PET system. In this paper, we present a DOI decoding method based on flood map for low-cost conventional block detector with four-PMT readout. Using this method, the DOI information can be directly extracted from the DOI-related crystal spot deformation in the flood map. GATE simulations are then carried out to validate the method, confirming a DOI sorting accuracy of 85.27%. Therefore, we conclude that this method has the potential to be applied in conventional detectors to achieve a reasonable DOI measurement without dramatically increasing their complexity and cost of an entire PET system.

Training sample selection based on self-training for liver cirrhosis classification using ultrasound images

NASA Astrophysics Data System (ADS)

Fujita, Yusuke; Mitani, Yoshihiro; Hamamoto, Yoshihiko; Segawa, Makoto; Terai, Shuji; Sakaida, Isao

2017-03-01

Ultrasound imaging is a popular and non-invasive tool used in the diagnoses of liver disease. Cirrhosis is a chronic liver disease and it can advance to liver cancer. Early detection and appropriate treatment are crucial to prevent liver cancer. However, ultrasound image analysis is very challenging, because of the low signal-to-noise ratio of ultrasound images. To achieve the higher classification performance, selection of training regions of interest (ROIs) is very important that effect to classification accuracy. The purpose of our study is cirrhosis detection with high accuracy using liver ultrasound images. In our previous works, training ROI selection by MILBoost and multiple-ROI classification based on the product rule had been proposed, to achieve high classification performance. In this article, we propose self-training method to select training ROIs effectively. Evaluation experiments were performed to evaluate effect of self-training, using manually selected ROIs and also automatically selected ROIs. Experimental results show that self-training for manually selected ROIs achieved higher classification performance than other approaches, including our conventional methods. The manually ROI definition and sample selection are important to improve classification accuracy in cirrhosis detection using ultrasound images.

The effects of traditional learning and a learning cycle inquiry learning strategy on students' science achievement and attitudes toward elementary science

NASA Astrophysics Data System (ADS)

Ebrahim, Ali

The purpose of this study is to examine the impact of two instructional methods on students' academic achievement and attitudes toward elementary science in the State of Kuwait: traditional teaching method and the 4-E learning cycle inquiry teaching method. The subjects were 111 students from four intact 4th grade classes. The experiment group (n = 56) received the learning cycle instruction while the control group (n = 55) received a more traditional approach over a four week period. The same female teacher taught the experimental and control groups for boys and a different female teacher taught experimental and control groups for girls. The dependent variables were measured through the use of: (1) a science achievement test to assess student achievement; and (2) an attitude survey to measure students' attitudes toward science. Quantitative data were collected on students' pre- and post-treatment achievement and attitudes measures. The two way MANOVA reveals that: the 4-E learning cycle instructional method produces significantly greater achievement and attitudes among fourth grade science students than the traditional teaching approach F (2, 93) = 19.765, (P = .000), corresponding to Wilks' Lambda = .702 with an effect size of .298 and a power of 1. In light of these findings, it is therefore suggested that students can achieve greater and have higher science attitudes when the 4-E learning cycle is used. In addition, these findings support the notion that effective instruction in teaching science, such as the 4-E learning cycle instruction, should be proposed and implemented in elementary schools.

Test-Retest Reliability of the National Health and Nutrition Examination Survey’s 5-Question Food Insecurity Survey Completed by Fourth-Grade Children

PubMed Central

Baxter, Suzanne D.; Smith, Albert F.; Hitchcock, David B.; Collins, Kathleen L.; Guinn, Caroline H.; Finney, Christopher J.; Royer, Julie A.; Miller, Patricia H.

2015-01-01

Objective To examine test-retest reliability and internal consistency of a 5-question food insecurity survey used in the National Health and Nutrition Examination Survey. Methods Researchers administered the National Health and Nutrition Examination Survey in the classroom to 92 fourth-grade children (74 African American; 48 girls) in 2 sessions 27–30 days apart in spring, 2011. Each classroom administration lasted 5–10 minutes. Results Test-retest reliability was 0.66 (Kendall tau), which is modest. Internal consistency (Cronbach alpha) was .67 and .70 for respective administrations. Food insecurity scores were related to gender (adjusted P = .05) and academic achievement (adjusted P = .004) but not to socioeconomic status or body mass index percentile (binomial regression). On average, boys reported higher food insecurity than girls. Children with lower academic achievement scores reported higher food insecurity than children with higher academic achievement scores. Conclusions and Implications The National Health and Nutrition Examination 5-question survey may be group administered to assess food insecurity efficiently as reported by individual fourth-grade children. PMID:26363937

Evaluation of an artificial intelligence guided inverse planning system: clinical case study.

PubMed

Yan, Hui; Yin, Fang-Fang; Willett, Christopher

2007-04-01

An artificial intelligence (AI) guided method for parameter adjustment of inverse planning was implemented on a commercial inverse treatment planning system. For evaluation purpose, four typical clinical cases were tested and the results from both plans achieved by automated and manual methods were compared. The procedure of parameter adjustment mainly consists of three major loops. Each loop is in charge of modifying parameters of one category, which is carried out by a specially customized fuzzy inference system. A physician prescribed multiple constraints for a selected volume were adopted to account for the tradeoff between prescription dose to the PTV and dose-volume constraints for critical organs. The searching process for an optimal parameter combination began with the first constraint, and proceeds to the next until a plan with acceptable dose was achieved. The initial setup of the plan parameters was the same for each case and was adjusted independently by both manual and automated methods. After the parameters of one category were updated, the intensity maps of all fields were re-optimized and the plan dose was subsequently re-calculated. When final plan arrived, the dose statistics were calculated from both plans and compared. For planned target volume (PTV), the dose for 95% volume is up to 10% higher in plans using the automated method than those using the manual method. For critical organs, an average decrease of the plan dose was achieved. However, the automated method cannot improve the plan dose for some critical organs due to limitations of the inference rules currently employed. For normal tissue, there was no significant difference between plan doses achieved by either automated or manual method. With the application of AI-guided method, the basic parameter adjustment task can be accomplished automatically and a comparable plan dose was achieved in comparison with that achieved by the manual method. Future improvements to incorporate case-specific inference rules are essential to fully automate the inverse planning process.

Facilitating organisational development using a group-based formative assessment and benchmarking method: design and implementation of the International Family Practice Maturity Matrix.

PubMed

Elwyn, Glyn; Bekkers, Marie-Jet; Tapp, Laura; Edwards, Adrian; Newcombe, Robert; Eriksson, Tina; Braspenning, Jozé; Kuch, Christine; Adzic, Zlata Ozvacic; Ayankogbe, Olayinka; Cvetko, Tatjana; In 't Veld, Kees; Karotsis, Antonis; Kersnik, Janko; Lefebvre, Luc; Mecini, Ilir; Petricek, Goranka; Pisco, Luis; Thesen, Janecke; Turón, José María; van Rossen, Edward; Grol, Richard

2010-12-01

Well-organised practices deliver higher-quality care. Yet there has been very little effort so far to help primary care organisations achieve higher levels of team performance and to help them identify and prioritise areas where quality improvement efforts should be concentrated. No attempt at all has been made to achieve a method which would be capable of providing comparisons--and the stimulus for further improvement--at an international level. The development of the International Family Practice Maturity Matrix took place in three phases: (1) selection and refinement of organisational dimensions; (2) development of incremental scales based on a recognised theoretical framework; and (3) testing the feasibility of the approach on an international basis, including generation of an automated web-based benchmarking system. This work has demonstrated the feasibility of developing an organisational assessment tool for primary care organisations that is sufficiently generic to cross international borders and is applicable across a diverse range of health settings, from state-organised systems to insurer-based health economies. It proved possible to introduce this assessment method in 11 countries in Europe and one in Africa, and to generate comparison benchmarks based on the data collected. The evaluation of the assessment process was uniformly positive with the view that the approach efficiently enables the identification of priorities for organisational development and quality improvement at the same time as motivating change by virtue of the group dynamics. We are not aware of any other organisational assessment method for primary care which has been 'born international,' and that has involved attention to theory, dimension selection and item refinement. The principal aims were to achieve an organisational assessment which gains added value by using interaction, engagement comparative benchmarks: aims which have been achieved. The next step is to achieve wider implementation and to ensure that those who undertake the assessment method ensure linkages are made to planned investment in organisational development and quality improvement. Knowing the problems is only half the story.

Object-Based Random Forest Classification of Land Cover from Remotely Sensed Imagery for Industrial and Mining Reclamation

NASA Astrophysics Data System (ADS)

Chen, Y.; Luo, M.; Xu, L.; Zhou, X.; Ren, J.; Zhou, J.

2018-04-01

The RF method based on grid-search parameter optimization could achieve a classification accuracy of 88.16 % in the classification of images with multiple feature variables. This classification accuracy was higher than that of SVM and ANN under the same feature variables. In terms of efficiency, the RF classification method performs better than SVM and ANN, it is more capable of handling multidimensional feature variables. The RF method combined with object-based analysis approach could highlight the classification accuracy further. The multiresolution segmentation approach on the basis of ESP scale parameter optimization was used for obtaining six scales to execute image segmentation, when the segmentation scale was 49, the classification accuracy reached the highest value of 89.58 %. The classification accuracy of object-based RF classification was 1.42 % higher than that of pixel-based classification (88.16 %), and the classification accuracy was further improved. Therefore, the RF classification method combined with object-based analysis approach could achieve relatively high accuracy in the classification and extraction of land use information for industrial and mining reclamation areas. Moreover, the interpretation of remotely sensed imagery using the proposed method could provide technical support and theoretical reference for remotely sensed monitoring land reclamation.

The effects of guided inquiry instruction on student achievement in high school biology

NASA Astrophysics Data System (ADS)

Vass, Laszlo

The purpose of this quantitative, quasi-experimental study was to measure the effect of a student-centered instructional method called guided inquiry on the achievement of students in a unit of study in high school biology. The study used a non-random sample of 109 students, the control group of 55 students enrolled in high school one, received teacher centered instruction while the experimental group of 54 students enrolled at high school two received student-centered, guided inquiry instruction. The pretest-posttest design of the study analyzed scores using an independent t-test, a dependent t-test (p = <.001), an ANCOVA (p = .007), mixed method ANOVA (p = .024) and hierarchical linear regression (p = <.001). The experimental group that received guided inquiry instruction had statistically significantly higher achievement than the control group.

Improved accuracy for finite element structural analysis via a new integrated force method

NASA Technical Reports Server (NTRS)

Patnaik, Surya N.; Hopkins, Dale A.; Aiello, Robert A.; Berke, Laszlo

1992-01-01

A comparative study was carried out to determine the accuracy of finite element analyses based on the stiffness method, a mixed method, and the new integrated force and dual integrated force methods. The numerical results were obtained with the following software: MSC/NASTRAN and ASKA for the stiffness method; an MHOST implementation method for the mixed method; and GIFT for the integrated force methods. The results indicate that on an overall basis, the stiffness and mixed methods present some limitations. The stiffness method generally requires a large number of elements in the model to achieve acceptable accuracy. The MHOST method tends to achieve a higher degree of accuracy for course models than does the stiffness method implemented by MSC/NASTRAN and ASKA. The two integrated force methods, which bestow simultaneous emphasis on stress equilibrium and strain compatibility, yield accurate solutions with fewer elements in a model. The full potential of these new integrated force methods remains largely unexploited, and they hold the promise of spawning new finite element structural analysis tools.

Drinking, smoking, and educational achievement: Cross-lagged associations from adolescence to adulthood

PubMed Central

Latvala, Antti; Rose, Richard J.; Pulkkinen, Lea; Dick, Danielle M.; Korhonen, Tellervo; Kaprio, Jaakko

2014-01-01

Background Adolescent substance use is associated with lower educational achievement but the directionality of the association remains uncertain. We analyzed data on drinking, smoking and educational achievement to study the associations between substance use and education from early adolescence to young adulthood. Methods Longitudinal data from four time points (ages 12, 14, 17, and 19-27 years) from a population-based cohort study of Finnish twin individuals were used to estimate bivariate cross-lagged path models for substance use and educational achievement, adjusting for sex, parental covariates, and adolescent externalizing behavior. A total of 4,761 individuals (49.4% females) were included in the analyses. Educational achievement was assessed with teacher-reported grade point average at ages 12 and 14, and with self-reported student status and completed education at age 17 and in young adulthood. From self-reported questionnaire items, frequency of any drinking, frequency of drinking to intoxication, any smoking and daily smoking were analyzed. Results Alcohol use and smoking behaviors at ages 12 and 14 predicted lower educational achievement at later time points even after previous achievement and confounding factors were taken into account. Lower school achievement in adolescence predicted a higher likelihood of engaging in smoking behaviors but did not predict later alcohol use. Higher educational attainment at age 17 predicted more frequent drinking in young adulthood. Conclusions Adolescent drinking behaviors are associated with lower future educational achievement independently of prior achievement, whereas smoking both predicts and is predicted by lower achievement. Early substance use indexes elevated risk for poor educational outcomes. PMID:24548801

Differences in motives between Millennial and Generation X medical students.

PubMed

Borges, Nicole J; Manuel, R Stephen; Elam, Carol L; Jones, Bonnie J

2010-06-01

OBJECTIVES Three domains comprise the field of human assessment: ability, motive and personality. Differences in personality and cognitive abilities between generations have been documented, but differences in motive between generations have not been explored. This study explored generational differences in medical students regarding motives using the Thematic Apperception Test (TAT). METHODS Four hundred and twenty six students (97% response rate) at one medical school (Generation X = 229, Millennials = 197) who matriculated in 1995 & 1996 (Generation X) or in 2003 & 2004 (Millennials) wrote a story after being shown two TAT picture cards. Student stories for each TAT card were scored for different aspects of motives: Achievement, Affiliation, and Power. RESULTS A multiple analysis of variance (p < 0.05) showed significant differences between Millennials' and Generation X-ers' needs for Power on both TAT cards and needs for Achievement and Affiliation on one TAT card. The main effect for gender was significant for both TAT cards regarding Achievement. No main effect for ethnicity was noted. CONCLUSIONS Differences in needs for Achievement, Affiliation and Power exist between Millennial and Generation X medical students. Generation X-ers scored higher on the motive of Power, whereas Millennials scored higher on the motives of Achievement and Affiliation.

Burnout, quality of life, motivation, and academic achievement among medical students: A person-oriented approach.

PubMed

Lyndon, Mataroria P; Henning, Marcus A; Alyami, Hussain; Krishna, Sanjeev; Zeng, Irene; Yu, Tzu-Chieh; Hill, Andrew G

2017-04-01

The aim of this study was to identify burnout and quality of life profiles of medical students and determine their associations with academic motivation and achievement on progress tests using a person-oriented approach. Medical students (n = 670) in Year 3 to Year 5 at the University of Auckland were classified into three different profiles as derived from a two-step cluster analysis using World Health Organization Quality of Life-BREF scores and Copenhagen Burnout Inventory scores. The profiles were used as independent variables to assess differences in academic motivation and achievement on progress tests using a multivariate analysis of co-variance and repeated measures analysis of co-variance methods. The response rate was 47%. Three clusters were obtained: Higher Burnout Lower Quality of Life (n = 62, 20%), Moderate Burnout Moderate Quality of Life (n = 131, 41%), and Lower Burnout Higher Quality of Life (n = 124, 39%). After controlling for gender and year level, Higher Burnout Lower Quality of Life students had significantly higher test anxiety (p < 0.0001) and amotivation scores (p < 0.0001); and lower intrinsic motivation (p < 0.005), self-efficacy (p < 0.001), and progress test scores (p = 0.03) compared with the other profiles. Burnout and Quality of Life profiles of medical students are associated with differences in academic motivation and achievement over time.

Cyclic volatile methylsiloxanes in human blood as markers for ruptured silicone gel-filled breast implants.

PubMed

Rosendahl, Pia; Hippler, Joerg; Schmitz, Oliver J; Hoffmann, Oliver; Rusch, Peter

2016-05-01

The replacement of medical-grade silicone with industrial-grade silicone material in some silicone gel-filled breast implants (SBI) manufactured by Poly Implant Prothèse and Rofil Medical Nederland B.V., reported in 2010, which resulted in a higher rupture tendency of these SBI, demonstrates the need for non-invasive, sensitive monitoring and screening methods. Therefore a sensitive method based on large volume injection-gas chromatography coupled to mass spectrometry (LVI-GC/MS) was developed to determine octamethylcyclotetrasiloxane (D4), decamethylcyclopentasiloxane (D5), and dodecamethylcyclo-hexasiloxane (D6) in blood samples from women with intact (n = 13) and ruptured SBI (n = 11). With dichloromethane extraction, sample cooling during preparation, and analysis extraction efficiencies up to 100 % and limits of detection of 0.03-0.05 ng D4-D6/g blood were achieved. Blood samples from women with SBI were investigated. In contrast to women with intact SBI, in blood from women with ruptured SBI higher D4 and D6 concentrations up to 0.57 ng D4/g blood and 0.16 ng D6/g blood were detected. With concentrations above 0.18 D4 ng/blood and 0.10 ng D6/g blood as significant criteria for ruptured SBI, this developed analytical preoperative diagnostic method shows a significant increase of the recognition rate. Finally a higher precision (error rate 17%) than the commonly used clinical diagnostic method, mamma sonography (error rate 46%), was achieved.

A 3-D enlarged cell technique (ECT) for elastic wave modelling of a curved free surface

NASA Astrophysics Data System (ADS)

Wei, Songlin; Zhou, Jianyang; Zhuang, Mingwei; Liu, Qing Huo

2016-09-01

The conventional finite-difference time-domain (FDTD) method for elastic waves suffers from the staircasing error when applied to model a curved free surface because of its structured grid. In this work, an improved, stable and accurate 3-D FDTD method for elastic wave modelling on a curved free surface is developed based on the finite volume method and enlarged cell technique (ECT). To achieve a sufficiently accurate implementation, a finite volume scheme is applied to the curved free surface to remove the staircasing error; in the mean time, to achieve the same stability as the FDTD method without reducing the time step increment, the ECT is introduced to preserve the solution stability by enlarging small irregular cells into adjacent cells under the condition of conservation of force. This method is verified by several 3-D numerical examples. Results show that the method is stable at the Courant stability limit for a regular FDTD grid, and has much higher accuracy than the conventional FDTD method.

Parental overprotection engenders dysfunctional attitudes about achievement and dependency in a gender-specific manner

PubMed Central

2013-01-01

Background It has been suggested that dysfunctional attitudes, cognitive vulnerability to depression, have developmental origins. The present study examined the effects of parental rearing on dysfunctional attitudes in three areas of life with special attention to gender specificity. Methods The subjects were 665 Japanese healthy volunteers. Dysfunctional attitudes were assessed by the 24-item Dysfunctional Attitude Scale, which has the Achievement, Dependency and Self-control subscales. Perceived parental rearing was assessed by the Parental Bonding Instrument, which has the Care and Protection subscales. Results Higher scores of the Achievement (β = 0.293, p < 0.01) and Dependency (β = 0.224, p < 0.05) subscales were correlated with higher scores of the Protection subscale in the combination of mother and daughter, but not in other combinations of parents and recipients. Scores of the Self-control subscale were not correlated with paternal or maternal rearing scores. Conclusions The present study suggests that parental overprotection engenders dysfunctional attitudes about achievement and dependency in a gender-specific manner. PMID:24365104

Management NVQs in Higher Education: Reflections on Experience.

ERIC Educational Resources Information Center

Swailes, Stephen

1997-01-01

Factors affecting achievement of National Vocational Qualifications in management include (1) candidate's self-motivation, ability to act on feedback, and report-writing skills; (2) employers support for evidence collection and mentoring; and (3) institutions use of suitable teaching methods and understanding of portfolio construction and…

Rotary drum composting of vegetable waste and tree leaves.

PubMed

Kalamdhad, Ajay S; Singh, Yatish K; Ali, Muntjeer; Khwairakpam, Meena; Kazmi, A A

2009-12-01

High rate composting studies on institutional waste, i.e. vegetable wastes, tree leaves, etc., were conducted on a demonstration-scale (3.5 m(3)) rotary drum composter by evaluating changes in some physico-chemical and biological parameters. During composting, higher temperature (60-70 degrees C) at inlet zone and (50-60 degrees C) at middle zone were achieved which resulted in high degradation in the drum. As a result, all parameters including TOC, C/N ratio, CO(2) evolution and coliforms were decreased significantly within few days of composting. Within a week period, quality compost with total nitrogen (2.6%) and final total phosphorus (6 g/kg) was achieved; but relatively higher final values of fecal coliforms and CO(2) evolution, suggested further maturation. Thus, two conventional composting methods namely windrow (M1) and vermicomposting (M2) tried for maturation of primary stabilized compost. By examining these methods, it was suggested that M2 was found suitable in delivering fine grained, better quality matured compost within 20 days of maturation period.

Highly Efficient Nd:yag Lasers for Free-space Optical Communications

NASA Technical Reports Server (NTRS)

Sipes, D. L., Jr.

1985-01-01

A highly efficient Nd:YAG laser end-pumped by semiconductor lasers as a possible free-space optical communications source is discussed. Because this concept affords high pumping densities, a long absorption length, and excellent mode-matching characteristics, it is estimated that electrical-to-optical efficiencies greater than 5% could be achieved. Several engineering aspects such as resonator size and configuration, pump collecting optics, and thermal effects are also discussed. Finally, possible methods for combining laser-diode pumps to achieve higher output powers are illustrated.

Incorporation of Tin on copper clad laminate to increase the interface adhesion for signal loss reduction of high-frequency PCB lamination

NASA Astrophysics Data System (ADS)

Wang, Chong; Wen, Na; Zhou, Guoyun; Wang, Shouxu; He, Wei; Su, Xinhong; Hu, Yongsuan

2017-11-01

A novel method of improving the adhesion between copper and prepreg in high frequency PCB was proposed and studied in this work. This process which aimed to decrease the IEP (isoelectric point) of the copper to obtain higher adhesion, was achieved by depositing a thin tin layer with lower IEP on copper. It was characterized by scanning electron microscopy (SEM), 3D microscope, peel strength test, X-Ray thickness test, grazing incidence X-ray diffraction (GXRD), X-ray photoelectron spectroscopy (XPS), Agilent vector network analyzer (VNA), which confirmed its excellent adhesion performance and outstanding electrical properties in high-frequency signal transmission compared with traditional brown oxide method. Moreover, the mechanism of achieving high adhesion for this method was also investigated.

International Harmonization and Cooperation in the Validation of Alternative Methods.

PubMed

Barroso, João; Ahn, Il Young; Caldeira, Cristiane; Carmichael, Paul L; Casey, Warren; Coecke, Sandra; Curren, Rodger; Desprez, Bertrand; Eskes, Chantra; Griesinger, Claudius; Guo, Jiabin; Hill, Erin; Roi, Annett Janusch; Kojima, Hajime; Li, Jin; Lim, Chae Hyung; Moura, Wlamir; Nishikawa, Akiyoshi; Park, HyeKyung; Peng, Shuangqing; Presgrave, Octavio; Singer, Tim; Sohn, Soo Jung; Westmoreland, Carl; Whelan, Maurice; Yang, Xingfen; Yang, Ying; Zuang, Valérie

The development and validation of scientific alternatives to animal testing is important not only from an ethical perspective (implementation of 3Rs), but also to improve safety assessment decision making with the use of mechanistic information of higher relevance to humans. To be effective in these efforts, it is however imperative that validation centres, industry, regulatory bodies, academia and other interested parties ensure a strong international cooperation, cross-sector collaboration and intense communication in the design, execution, and peer review of validation studies. Such an approach is critical to achieve harmonized and more transparent approaches to method validation, peer-review and recommendation, which will ultimately expedite the international acceptance of valid alternative methods or strategies by regulatory authorities and their implementation and use by stakeholders. It also allows achieving greater efficiency and effectiveness by avoiding duplication of effort and leveraging limited resources. In view of achieving these goals, the International Cooperation on Alternative Test Methods (ICATM) was established in 2009 by validation centres from Europe, USA, Canada and Japan. ICATM was later joined by Korea in 2011 and currently also counts with Brazil and China as observers. This chapter describes the existing differences across world regions and major efforts carried out for achieving consistent international cooperation and harmonization in the validation and adoption of alternative approaches to animal testing.

A comparison of two methods of teaching. Computer managed instruction and keypad questions versus traditional classroom lecture.

PubMed

Halloran, L

1995-01-01

Computers increasingly are being integrated into nursing education. One method of integration is through computer managed instruction (CMI). Recently, technology has become available that allows the integration of keypad questions into CMI. This brings a new type of interactivity between students and teachers into the classroom. The purpose of this study was to evaluate differences in achievement between a control group taught by traditional classroom lecture (TCL) and an experimental group taught using CMI and keypad questions. Both control and experimental groups consisted of convenience samples of junior nursing students in a baccalaureate program taking a medical/surgical nursing course. Achievement was measured by three instructor-developed multiple choice examinations. Findings demonstrated that although the experimental group demonstrated increasingly higher test scores as the semester progressed, no statistical difference was found in achievement between the two groups. One reason for this may be phenomenon of vampire video. Initially, the method of presentation overshadowed the content. As students became desensitized to the method, they were able to focus and absorb more content. This study suggests that CMI and keypads are a viable teaching option for nursing education. It is equal to TCL in student achievement and provides a new level of interaction in the classroom setting.

Thermal-noise-limited higher-order mode locking of a reference cavity

NASA Astrophysics Data System (ADS)

Zeng, X. Y.; Ye, Y. X.; Shi, X. H.; Wang, Z. Y.; Deng, K.; Zhang, J.; Lu, Z. H.

2018-04-01

Higher-order mode locking has been proposed to reduce the thermal noise limit of reference cavities. By locking a laser to the HG02 mode of a 10-cm long all ULE cavity, and measure its performance with the three-cornered-hat method among three independently stabilized lasers, we demonstrate a thermal noise limited performance of a fractional frequency instability of 4.9E-16. The results match the theoretical models with higher-order optical modes. The achieved laser instability improves the all ULE short cavity results to a new low level.

Quantitative Guidance for Stove Usage and Performance to Achieve Health and Environmental Targets

PubMed Central

Chiang, Ranyee A.

2015-01-01

Background Displacing the use of polluting and inefficient cookstoves in developing countries is necessary to achieve the potential health and environmental benefits sought through clean cooking solutions. Yet little quantitative context has been provided on how much displacement of traditional technologies is needed to achieve targets for household air pollutant concentrations or fuel savings. Objectives This paper provides instructive guidance on the usage of cooking technologies required to achieve health and environmental improvements. Methods We evaluated different scenarios of displacement of traditional stoves with use of higher performing technologies. The air quality and fuel consumption impacts were estimated for these scenarios using a single-zone box model of indoor air quality and ratios of thermal efficiency. Results Stove performance and usage should be considered together, as lower performing stoves can result in similar or greater benefits than a higher performing stove if the lower performing stove has considerably higher displacement of the baseline stove. Based on the indoor air quality model, there are multiple performance–usage scenarios for achieving modest indoor air quality improvements. To meet World Health Organization guidance levels, however, three-stone fire and basic charcoal stove usage must be nearly eliminated to achieve the particulate matter target (< 1–3 hr/week), and substantially limited to meet the carbon monoxide guideline (< 7–9 hr/week). Conclusions Moderate health gains may be achieved with various performance–usage scenarios. The greatest benefits are estimated to be achieved by near-complete displacement of traditional stoves with clean technologies, emphasizing the need to shift in the long term to near exclusive use of clean fuels and stoves. The performance–usage scenarios are also provided as a tool to guide technology selection and prioritize behavior change opportunities to maximize impact. Citation Johnson MA, Chiang RA. 2015. Quantitative guidance for stove usage and performance to achieve health and environmental targets. Environ Health Perspect 123:820–826; http://dx.doi.org/10.1289/ehp.1408681 PMID:25816219

Lattice Boltzmann approach for complex nonequilibrium flows.

PubMed

Montessori, A; Prestininzi, P; La Rocca, M; Succi, S

2015-10-01

We present a lattice Boltzmann realization of Grad's extended hydrodynamic approach to nonequilibrium flows. This is achieved by using higher-order isotropic lattices coupled with a higher-order regularization procedure. The method is assessed for flow across parallel plates and three-dimensional flows in porous media, showing excellent agreement of the mass flow with analytical and numerical solutions of the Boltzmann equation across the full range of Knudsen numbers, from the hydrodynamic regime to ballistic motion.

Neurology clerkship goals and their effect on learning and satisfaction

PubMed Central

Salas, Rachel Marie E.; Cruz, Tiana E.; Gamaldo, Charlene E.

2016-01-01

Objective: To define medical student goals in the neurology clerkship and explore the association between goal setting and student performance, clerkship satisfaction, self-directed learning (SDL), and interest in neurology. Methods: A 4-year prospective study of consecutive second- to fourth-year medical students rotating through a required 4-week neurology clerkship was conducted. A goal-generating cohort (first 2 years) was enrolled to describe the breadth of student-derived goals. A goal-evaluating cohort (second 2 years) was used to evaluate the frequency of goal achievement and assess associations with performance (e.g., National Board of Medical Examiners [NBME], examination), satisfaction, and SDL behaviors (both based on 5-point Likert scale). Results: Of 440 evaluable students, 201 were goal-generating and 239 goal-evaluating. The top 3 goals were (1) improvement in neurologic examination, (2) understanding neurologic disease, and (3) deriving a differential diagnosis. More than 90% (n = 216/239) of students reported achieving goals. Achievers reported significantly higher clerkship satisfaction (4.2 ± 0.8 vs 2.8 ± 1.0, p < 0.0001), greater interest in neurology (71% vs 35%, p = 0.001), and higher observed tendency toward SDL (4.5 ± 0.5 vs 4.1 ± 0.8, p < 0.0001). After adjusting for age and training, NBME scores were 1.7 points higher in achievers (95% confidence interval 0.1–3.2, p = 0.04). Conclusion: Students consistently generated similar goals for a required neurology clerkship. Goal achievers had better adjusted standardized test scores, higher satisfaction, and greater tendency toward SDL. This student-generated, goal-setting program may be particularly appealing to clinicians, educators, and researchers seeking resource-lean mechanisms to improve student experience and performance in the clinical clerkships. PMID:26718569

Precise attitude rate estimation using star images obtained by mission telescope for satellite missions

NASA Astrophysics Data System (ADS)

Inamori, Takaya; Hosonuma, Takayuki; Ikari, Satoshi; Saisutjarit, Phongsatorn; Sako, Nobutada; Nakasuka, Shinichi

2015-02-01

Recently, small satellites have been employed in various satellite missions such as astronomical observation and remote sensing. During these missions, the attitudes of small satellites should be stabilized to a higher accuracy to obtain accurate science data and images. To achieve precise attitude stabilization, these small satellites should estimate their attitude rate under the strict constraints of mass, space, and cost. This research presents a new method for small satellites to precisely estimate angular rate using star blurred images by employing a mission telescope to achieve precise attitude stabilization. In this method, the angular velocity is estimated by assessing the quality of a star image, based on how blurred it appears to be. Because the proposed method utilizes existing mission devices, a satellite does not require additional precise rate sensors, which makes it easier to achieve precise stabilization given the strict constraints possessed by small satellites. The research studied the relationship between estimation accuracy and parameters used to achieve an attitude rate estimation, which has a precision greater than 1 × 10-6 rad/s. The method can be applied to all attitude sensors, which use optics systems such as sun sensors and star trackers (STTs). Finally, the method is applied to the nano astrometry satellite Nano-JASMINE, and we investigate the problems that are expected to arise with real small satellites by performing numerical simulations.

Deep-learning: investigating deep neural networks hyper-parameters and comparison of performance to shallow methods for modeling bioactivity data.

PubMed

Koutsoukas, Alexios; Monaghan, Keith J; Li, Xiaoli; Huan, Jun

2017-06-28

In recent years, research in artificial neural networks has resurged, now under the deep-learning umbrella, and grown extremely popular. Recently reported success of DL techniques in crowd-sourced QSAR and predictive toxicology competitions has showcased these methods as powerful tools in drug-discovery and toxicology research. The aim of this work was dual, first large number of hyper-parameter configurations were explored to investigate how they affect the performance of DNNs and could act as starting points when tuning DNNs and second their performance was compared to popular methods widely employed in the field of cheminformatics namely Naïve Bayes, k-nearest neighbor, random forest and support vector machines. Moreover, robustness of machine learning methods to different levels of artificially introduced noise was assessed. The open-source Caffe deep-learning framework and modern NVidia GPU units were utilized to carry out this study, allowing large number of DNN configurations to be explored. We show that feed-forward deep neural networks are capable of achieving strong classification performance and outperform shallow methods across diverse activity classes when optimized. Hyper-parameters that were found to play critical role are the activation function, dropout regularization, number hidden layers and number of neurons. When compared to the rest methods, tuned DNNs were found to statistically outperform, with p value <0.01 based on Wilcoxon statistical test. DNN achieved on average MCC units of 0.149 higher than NB, 0.092 than kNN, 0.052 than SVM with linear kernel, 0.021 than RF and finally 0.009 higher than SVM with radial basis function kernel. When exploring robustness to noise, non-linear methods were found to perform well when dealing with low levels of noise, lower than or equal to 20%, however when dealing with higher levels of noise, higher than 30%, the Naïve Bayes method was found to perform well and even outperform at the highest level of noise 50% more sophisticated methods across several datasets.

Tild-CRISPR Allows for Efficient and Precise Gene Knockin in Mouse and Human Cells.

PubMed

Yao, Xuan; Zhang, Meiling; Wang, Xing; Ying, Wenqin; Hu, Xinde; Dai, Pengfei; Meng, Feilong; Shi, Linyu; Sun, Yun; Yao, Ning; Zhong, Wanxia; Li, Yun; Wu, Keliang; Li, Weiping; Chen, Zi-Jiang; Yang, Hui

2018-05-21

The targeting efficiency of knockin sequences via homologous recombination (HR) is generally low. Here we describe a method we call Tild-CRISPR (targeted integration with linearized dsDNA-CRISPR), a targeting strategy in which a PCR-amplified or precisely enzyme-cut transgene donor with 800-bp homology arms is injected with Cas9 mRNA and single guide RNA into mouse zygotes. Compared with existing targeting strategies, this method achieved much higher knockin efficiency in mouse embryos, as well as brain tissue. Importantly, the Tild-CRISPR method also yielded up to 12-fold higher knockin efficiency than HR-based methods in human embryos, making it suitable for studying gene functions in vivo and developing potential gene therapies. Copyright © 2018 Elsevier Inc. All rights reserved.

Systematic network coding for two-hop lossy transmissions

NASA Astrophysics Data System (ADS)

Li, Ye; Blostein, Steven; Chan, Wai-Yip

2015-12-01

In this paper, we consider network transmissions over a single or multiple parallel two-hop lossy paths. These scenarios occur in applications such as sensor networks or WiFi offloading. Random linear network coding (RLNC), where previously received packets are re-encoded at intermediate nodes and forwarded, is known to be a capacity-achieving approach for these networks. However, a major drawback of RLNC is its high encoding and decoding complexity. In this work, a systematic network coding method is proposed. We show through both analysis and simulation that the proposed method achieves higher end-to-end rate as well as lower computational cost than RLNC for finite field sizes and finite-sized packet transmissions.

Teaching Introductory Chemistry with Videocassette Presentations.

ERIC Educational Resources Information Center

Enger, John; And Others

Reported here is the development and evaluation of an extensive series of video-cassette presentations developed for introductory chemical education. In measures of course achievement, students instructed by the video-cassette-discussion format received higher average scores than those taught by live lecture methods. A survey showed that the…

Flipped Learning With Simulation in Undergraduate Nursing Education.

PubMed

Kim, HeaRan; Jang, YounKyoung

2017-06-01

Flipped learning has proliferated in various educational environments. This study aimed to verify the effects of flipped learning on the academic achievement, teamwork skills, and satisfaction levels of undergraduate nursing students. For the flipped learning group, simulation-based education via the flipped learning method was provided, whereas traditional, simulation-based education was provided for the control group. After completion of the program, academic achievement, teamwork skills, and satisfaction levels were assessed and analyzed. The flipped learning group received higher scores on academic achievement, teamwork skills, and satisfaction levels than the control group, including the areas of content knowledge and clinical nursing practice competency. In addition, this difference gradually increased between the two groups throughout the trial. The results of this study demonstrated the positive, statistically significant effects of the flipped learning method on simulation-based nursing education. [J Nurs Educ. 2017;56(6):329-336.]. Copyright 2017, SLACK Incorporated.

Estimation of Spatiotemporal Sensitivity Using Band-limited Signals with No Additional Acquisitions for k-t Parallel Imaging.

PubMed

Takeshima, Hidenori; Saitoh, Kanako; Nitta, Shuhei; Shiodera, Taichiro; Takeguchi, Tomoyuki; Bannae, Shuhei; Kuhara, Shigehide

2018-03-13

Dynamic MR techniques, such as cardiac cine imaging, benefit from shorter acquisition times. The goal of the present study was to develop a method that achieves short acquisition times, while maintaining a cost-effective reconstruction, for dynamic MRI. k - t sensitivity encoding (SENSE) was identified as the base method to be enhanced meeting these two requirements. The proposed method achieves a reduction in acquisition time by estimating the spatiotemporal (x - f) sensitivity without requiring the acquisition of the alias-free signals, typical of the k - t SENSE technique. The cost-effective reconstruction, in turn, is achieved by a computationally efficient estimation of the x - f sensitivity from the band-limited signals of the aliased inputs. Such band-limited signals are suitable for sensitivity estimation because the strongly aliased signals have been removed. For the same reduction factor 4, the net reduction factor 4 for the proposed method was significantly higher than the factor 2.29 achieved by k - t SENSE. The processing time is reduced from 4.1 s for k - t SENSE to 1.7 s for the proposed method. The image quality obtained using the proposed method proved to be superior (mean squared error [MSE] ± standard deviation [SD] = 6.85 ± 2.73) compared to the k - t SENSE case (MSE ± SD = 12.73 ± 3.60) for the vertical long-axis (VLA) view, as well as other views. In the present study, k - t SENSE was identified as a suitable base method to be improved achieving both short acquisition times and a cost-effective reconstruction. To enhance these characteristics of base method, a novel implementation is proposed, estimating the x - f sensitivity without the need for an explicit scan of the reference signals. Experimental results showed that the acquisition, computational times and image quality for the proposed method were improved compared to the standard k - t SENSE method.

Discontinuous Spectral Difference Method for Conservation Laws on Unstructured Grids

NASA Technical Reports Server (NTRS)

Liu, Yen; Vinokur, Marcel; Wang, Z. J.

2004-01-01

A new, high-order, conservative, and efficient method for conservation laws on unstructured grids is developed. The concept of discontinuous and high-order local representations to achieve conservation and high accuracy is utilized in a manner similar to the Discontinuous Galerkin (DG) and the Spectral Volume (SV) methods, but while these methods are based on the integrated forms of the equations, the new method is based on the differential form to attain a simpler formulation and higher efficiency. A discussion on the Discontinuous Spectral Difference (SD) Method, locations of the unknowns and flux points and numerical results are also presented.

Searching for the Golden Model of Education: Cross-National Analysis of Math Achievement

PubMed Central

Bodovski, Katerina; Byun, Soo-yong; Chykina, Volha; Chung, Hee Jin

2017-01-01

We utilized four waves of TIMSS data in addition to the information we have collected on countries’ educational systems to examine whether different degrees of standardization, differentiation, proportion of students in private schools and governmental spending on education influence students’ math achievement, its variation and socioeconomic status (SES) gaps in math achievement. Findings: A higher level of standardization of educational systems was associated with higher average math achievement. Greater expenditure on education (as % of total government expenditure) was associated with a lower level of dispersion of math achievement and smaller SES gaps in math achievement. Wealthier countries exhibited higher average math achievement and a narrower variation. Higher income inequality (measured by Gini index) was associated with a lower average math achievement and larger SES gaps. Further, we found that higher level of standardization alleviates the negative effects of differentiation in the systems with more rigid tracking. PMID:29151667

Simplified stereo-optical ultrasound plane calibration

NASA Astrophysics Data System (ADS)

Hoßbach, Martin; Noll, Matthias; Wesarg, Stefan

2013-03-01

Image guided therapy is a natural concept and commonly used in medicine. In anesthesia, a common task is the injection of an anesthetic close to a nerve under freehand ultrasound guidance. Several guidance systems exist using electromagnetic tracking of the ultrasound probe as well as the needle, providing the physician with a precise projection of the needle into the ultrasound image. This, however, requires additional expensive devices. We suggest using optical tracking with miniature cameras attached to a 2D ultrasound probe to achieve a higher acceptance among physicians. The purpose of this paper is to present an intuitive method to calibrate freehand ultrasound needle guidance systems employing a rigid stereo camera system. State of the art methods are based on a complex series of error prone coordinate system transformations which makes them susceptible to error accumulation. By reducing the amount of calibration steps to a single calibration procedure we provide a calibration method that is equivalent, yet not prone to error accumulation. It requires a linear calibration object and is validated on three datasets utilizing di erent calibration objects: a 6mm metal bar and a 1:25mm biopsy needle were used for experiments. Compared to existing calibration methods for freehand ultrasound needle guidance systems, we are able to achieve higher accuracy results while additionally reducing the overall calibration complexity. Ke

Continuous method of producing silicon carbide fibers

NASA Technical Reports Server (NTRS)

Barnard, Thomas Duncan (Inventor); Nguyen, Kimmai Thi (Inventor); Rabe, James Alan (Inventor)

1999-01-01

This invention pertains to a method for production of polycrystalline ceramic fibers from silicon oxycarbide (SiCO) ceramic fibers wherein the method comprises heating an amorphous ceramic fiber containing silicon and carbon in an inert environment comprising a boron oxide and carbon monoxide at a temperature sufficient to convert the amorphous ceramic fiber to a polycrystalline ceramic fiber. By having carbon monoxide present during the heating of the ceramic fiber, it is possible to achieve higher production rates on a continuous process.

Good Practices for Learning to Recognize Actions Using FV and VLAD.

PubMed

Wu, Jianxin; Zhang, Yu; Lin, Weiyao

2016-12-01

High dimensional representations such as Fisher vectors (FV) and vectors of locally aggregated descriptors (VLAD) have shown state-of-the-art accuracy for action recognition in videos. The high dimensionality, on the other hand, also causes computational difficulties when scaling up to large-scale video data. This paper makes three lines of contributions to learning to recognize actions using high dimensional representations. First, we reviewed several existing techniques that improve upon FV or VLAD in image classification, and performed extensive empirical evaluations to assess their applicability for action recognition. Our analyses of these empirical results show that normality and bimodality are essential to achieve high accuracy. Second, we proposed a new pooling strategy for VLAD and three simple, efficient, and effective transformations for both FV and VLAD. Both proposed methods have shown higher accuracy than the original FV/VLAD method in extensive evaluations. Third, we proposed and evaluated new feature selection and compression methods for the FV and VLAD representations. This strategy uses only 4% of the storage of the original representation, but achieves comparable or even higher accuracy. Based on these contributions, we recommend a set of good practices for action recognition in videos for practitioners in this field.

Substance use, substance abuse, and LD among adolescents with a childhood history of ADHD.

PubMed

Molina, B S; Pelham, W E

2001-01-01

A clinic-referred sample of 109 children with attention-deficit/hyperactivity disorder (ADHD) was followed into adolescence for the ascertainment of alcohol and other drug use and abuse. Learning disability (reading or math) in childhood was examined as a predictor of adolescent substance use and substance use disorder for alcohol and marijuana. No statistically significant group differences for children with LD versus those without LD emerged even after using different methods to compute LD. IQ/achievement discrepancy scores were similarly not predictive of later use or abuse. However, children with ADHD who had higher IQs and higher levels of academic achievement in childhood were more likely to try cigarettes, to smoke daily, and to have their first drink of alcohol or first cigarette at an early age. Children with ADHD who had higher reading achievement scores were less likely to have later alcohol use disorder. Although these findings are necessarily preliminary, due to the small number of children interviewed, the pattern of results suggests that level of cognitive functioning--rather than discrepancy between IQ and achievement--is important for the prediction of later substance use and abuse, at least in this clinic-referred sample of children with ADHD. Further, different mechanisms of risk related to cognitive functioning may be operating for experimentation with legal drugs such as alcohol and tobacco, regular cigarette smoking, and problematic alcohol use.

User Experience and Heritage Preservation

ERIC Educational Resources Information Center

Orfield, Steven J.; Chapman, J. Wesley; Davis, Nathan

2011-01-01

In considering the heritage preservation of higher education campus buildings, much of the attention gravitates toward issues of selection, cost, accuracy, and value, but the model for most preservation projects does not have a clear method of achieving the best solutions for meeting these targets. Instead, it simply relies on the design team and…

Using Scenarios and Simulations to Plan Colleges

ERIC Educational Resources Information Center

McIntyre, Chuck

2004-01-01

Using a case study, this article describes a method by which higher education institutions construct and use multiple future scenarios and simulations to plan strategically: to create visions of their futures, chart broad directions (mission and goals), and select learning and delivery strategies so as to achieve those broad directions. The…

Service Learning: An Auditing Project Study

ERIC Educational Resources Information Center

Laing, Gregory Kenneth

2013-01-01

There is a growing demand in higher education for universities to introduce teaching methods that achieve the learning outcomes of vocational education. The need for vocational educational outcomes was met in this study involving a service learning activity designed to provide basic professional auditing competencies. The details of the design and…

All Things Being Equal: Observing Australian Individual Academic Workloads

ERIC Educational Resources Information Center

Dobele, Angela; Rundle-Thiele, Sharyn; Kopanidis, Foula; Steel, Marion

2010-01-01

The achievement of greater gender equity within Australian universities is a significant issue for both the quality and the strength of Australian higher education. This paper contributes to our knowledge of academic workloads, observing individual workloads in business faculties. A multiple case study method was employed to observe individual…

Enhancing Teacher Education Students' Generic Skills through Problem-Based Learning

ERIC Educational Resources Information Center

Murray-Harvey, Rosalind; Curtis, David D.; Cattley, Georgina; Slee, Phillip T.

2005-01-01

Claims made for the value of problem-based learning (PBL) as an effective method for professional education programmes draw on constructivist principles of teaching and learning to achieve essential content knowledge, higher order thinking skills, and a team approach to problem-solving through the interdisciplinary, student-directed study of…

Transformative Learning Factors to Enhance Integral Healthy Organizations

ERIC Educational Resources Information Center

Thavinpipatkul, Chanchai; Ratana-Ubol, Archanya; Charungkaittikul, Suwithida

2016-01-01

This article focuses on how organizations search for the key factors to develop integral changes and determine broader and higher transcendental learning skills in order to achieve healthy and sustainable organizational growth more effectively and efficiently. This study employed qualitative approaches. The research method used is an in-depth…

Student Laptop Use and Scores on Standardized Tests

ERIC Educational Resources Information Center

Kposowa, Augustine J.; Valdez, Amanda D.

2013-01-01

Objectives: The primary objective of the study was to investigate the relationship between ubiquitous laptop use and academic achievement. It was hypothesized that students with ubiquitous laptops would score on average higher on standardized tests than those without such computers. Methods: Data were obtained from two sources. First, demographic…

Scan statistics with local vote for target detection in distributed system

NASA Astrophysics Data System (ADS)

Luo, Junhai; Wu, Qi

2017-12-01

Target detection has occupied a pivotal position in distributed system. Scan statistics, as one of the most efficient detection methods, has been applied to a variety of anomaly detection problems and significantly improves the probability of detection. However, scan statistics cannot achieve the expected performance when the noise intensity is strong, or the signal emitted by the target is weak. The local vote algorithm can also achieve higher target detection rate. After the local vote, the counting rule is always adopted for decision fusion. The counting rule does not use the information about the contiguity of sensors but takes all sensors' data into consideration, which makes the result undesirable. In this paper, we propose a scan statistics with local vote (SSLV) method. This method combines scan statistics with local vote decision. Before scan statistics, each sensor executes local vote decision according to the data of its neighbors and its own. By combining the advantages of both, our method can obtain higher detection rate in low signal-to-noise ratio environment than the scan statistics. After the local vote decision, the distribution of sensors which have detected the target becomes more intensive. To make full use of local vote decision, we introduce a variable-step-parameter for the SSLV. It significantly shortens the scan period especially when the target is absent. Analysis and simulations are presented to demonstrate the performance of our method.

Frequency Up-Converted Low Frequency Vibration Energy Harvester Using Trampoline Effect

NASA Astrophysics Data System (ADS)

Ju, S.; Chae, S. H.; Choi, Y.; Jun, S.; Park, S. M.; Lee, S.; Lee, H. W.; Ji, C.-H.

2013-12-01

This paper presents a non-resonant vibration energy harvester based on magnetoelectric transduction mechanism and mechanical frequency up-conversion using trampoline effect. The harvester utilizes a freely movable spherical permanent magnet which bounces off the aluminum springs integrated at both ends of the cavity, achieving frequency up-conversion from low frequency input vibration. Moreover, bonding method of magnetoelectric laminate composite has been optimized to provide higher strain to piezoelectric material and thus obtain a higher output voltage. A proof-of-concept energy harvesting device has been fabricated and tested. Maximum open-circuit voltage of 11.2V has been obtained and output power of 0.57μW has been achieved for a 50kΩ load, when the fabricated energy harvester was hand-shaken.

Electrophysiological dynamic brain connectivity during symbolic magnitude comparison in children with different mathematics achievement levels.

PubMed

Gómez-Velázquez, Fabiola R; Vélez-Pérez, Hugo; Espinoza-Valdez, Aurora; Romo-Vazquez, Rebeca; Salido-Ruiz, Ricardo A; Ruiz-Stovel, Vanessa; Gallardo-Moreno, Geisa B; González-Garrido, Andrés A; Berumen, Gustavo

2017-02-08

Children with mathematical difficulties usually have an impaired ability to process symbolic representations. Functional MRI methods have suggested that early frontoparietal connectivity can predict mathematic achievements; however, the study of brain connectivity during numerical processing remains unexplored. With the aim of evaluating this in children with different math proficiencies, we selected a sample of 40 children divided into two groups [high achievement (HA) and low achievement (LA)] according to their arithmetic scores in the Wide Range Achievement Test, 4th ed.. Participants performed a symbolic magnitude comparison task (i.e. determining which of two numbers is numerically larger), with simultaneous electrophysiological recording. Partial directed coherence and graph theory methods were used to estimate and depict frontoparietal connectivity in both groups. The behavioral measures showed that children with LA performed significantly slower and less accurately than their peers in the HA group. Significantly higher frontocentral connectivity was found in LA compared with HA; however, when the connectivity analysis was restricted to parietal locations, no relevant group differences were observed. These findings seem to support the notion that LA children require greater memory and attentional efforts to meet task demands, probably affecting early stages of symbolic comparison.

Patterns of care study of brachytherapy in New South Wales: cervical cancer treatment quality depends on caseload

PubMed Central

Delaney, Geoff P.; Gabriel, Gabriel S.; Barton, Michael B.

2014-01-01

Purpose We previously conducted modelling and a patterns of care study (POCS) that showed gynaecological brachytherapy (BT) was underutilized in New South Wales (NSW), the USA and Western Europe. The aim of the current study was to assess the quality of cervical BT in NSW, and to determine if caseload affects quality of treatment delivery. Material and methods All nine NSW radiation oncology departments that treated patients with cervical BT in 2003 were visited. Patient, tumour and treatment related data were collected. Quality of BT was assessed using published quality benchmarks. Higher and lower caseload departments were compared. Results The four higher cervical BT caseload departments treated 11-15 NSW residents in 2003, compared to 1-8 patients for the lower caseload departments. Cervix cancer patients treated at the higher caseload departments were more likely to be treated to a point A dose ≥ 80 Gy (58% vs. 14%, p = 0.001), and to have treatment completed within 8 weeks (66% vs. 35%, p = 0.02). Despite higher point A doses, there was no significant difference in proportions achieving lower than recommended rectal or bladder doses, implying better BT insertions in higher caseload departments. Conclusions Cervical BT in NSW was dispersed amongst a large number of departments and was frequently of sub-optimal quality. Higher quality BT was achieved in departments treating at least 10 patients per year. It is likely that improved outcomes will be achievable if at least 10 patients are treated per department per year. PMID:24790619

The application of the mesh-free method in the numerical simulations of the higher-order continuum structures

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sun, Yuzhou, E-mail: yuzhousun@126.com; Chen, Gensheng; Li, Dongxia

2016-06-08

This paper attempts to study the application of mesh-free method in the numerical simulations of the higher-order continuum structures. A high-order bending beam considers the effect of the third-order derivative of deflections, and can be viewed as a one-dimensional higher-order continuum structure. The moving least-squares method is used to construct the shape function with the high-order continuum property, the curvature and the third-order derivative of deflections are directly interpolated with nodal variables and the second- and third-order derivative of the shape function, and the mesh-free computational scheme is establish for beams. The coupled stress theory is introduced to describe themore » special constitutive response of the layered rock mass in which the bending effect of thin layer is considered. The strain and the curvature are directly interpolated with the nodal variables, and the mesh-free method is established for the layered rock mass. The good computational efficiency is achieved based on the developed mesh-free method, and some key issues are discussed.« less

Finite Element Analysis in Concurrent Processing: Computational Issues

NASA Technical Reports Server (NTRS)

Sobieszczanski-Sobieski, Jaroslaw; Watson, Brian; Vanderplaats, Garrett

2004-01-01

The purpose of this research is to investigate the potential application of new methods for solving large-scale static structural problems on concurrent computers. It is well known that traditional single-processor computational speed will be limited by inherent physical limits. The only path to achieve higher computational speeds lies through concurrent processing. Traditional factorization solution methods for sparse matrices are ill suited for concurrent processing because the null entries get filled, leading to high communication and memory requirements. The research reported herein investigates alternatives to factorization that promise a greater potential to achieve high concurrent computing efficiency. Two methods, and their variants, based on direct energy minimization are studied: a) minimization of the strain energy using the displacement method formulation; b) constrained minimization of the complementary strain energy using the force method formulation. Initial results indicated that in the context of the direct energy minimization the displacement formulation experienced convergence and accuracy difficulties while the force formulation showed promising potential.

Relativistic Spacecraft Propelled by Directed Energy

NASA Astrophysics Data System (ADS)

Kulkarni, Neeraj; Lubin, Philip; Zhang, Qicheng

2018-04-01

Achieving relativistic flight to enable extrasolar exploration is one of the dreams of humanity and the long-term goal of our NASA Starlight program. We derive a relativistic solution for the motion of a spacecraft propelled by radiation pressure from a directed energy (DE) system. Depending on the system parameters, low-mass spacecraft can achieve relativistic speeds, thus enabling interstellar exploration. The diffraction of the DE system plays an important role and limits the maximum speed of the spacecraft. We consider “photon recycling” as a possible method to achieving higher speeds. We also discuss recent claims that our previous work on this topic is incorrect and show that these claims arise from an improper treatment of causality.

Thermal-noise-limited higher-order mode locking of a reference cavity.

PubMed

Zeng, X Y; Ye, Y X; Shi, X H; Wang, Z Y; Deng, K; Zhang, J; Lu, Z H

2018-04-15

Higher-order mode locking has been proposed to reduce the thermal noise limit of reference cavities. By locking a laser to the HG 02 mode of a 10-cm long all ultra-low expansion (ULE) cavity and measuring its performance with the three-cornered-hat method among three independently stabilized lasers, we demonstrate a thermal-noise-limited performance of a fractional frequency instability of 4.9×10 -16 . The results match the theoretical models with higher-order optical modes. The achieved laser instability improves the all ULE short cavity results to a new low level.

New developments in fabrication of high-energy-resolution analyzers for inelastic x-ray spectroscopy.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Said, A. H.; Sinn, H.; Divan, R.

2011-05-01

In this work new improvements related to the fabrication of spherical bent analyzers for 1 meV energy-resolution inelastic X-ray scattering spectroscopy are presented. The new method includes the use of a two-dimensional bender to achieve the required radius of curvature for X-ray analyzers. The advantage of this method is the ability to monitor the focus during bending, which leads to higher-efficiency analyzers.

Building robust conservation plans.

PubMed

Visconti, Piero; Joppa, Lucas

2015-04-01

Systematic conservation planning optimizes trade-offs between biodiversity conservation and human activities by accounting for socioeconomic costs while aiming to achieve prescribed conservation objectives. However, the most cost-efficient conservation plan can be very dissimilar to any other plan achieving the set of conservation objectives. This is problematic under conditions of implementation uncertainty (e.g., if all or part of the plan becomes unattainable). We determined through simulations of parallel implementation of conservation plans and habitat loss the conditions under which optimal plans have limited chances of implementation and where implementation attempts would fail to meet objectives. We then devised a new, flexible method for identifying conservation priorities and scheduling conservation actions. This method entails generating a number of alternative plans, calculating the similarity in site composition among all plans, and selecting the plan with the highest density of neighboring plans in similarity space. We compared our method with the classic method that maximizes cost efficiency with synthetic and real data sets. When implementation was uncertain--a common reality--our method provided higher likelihood of achieving conservation targets. We found that χ, a measure of the shortfall in objectives achieved by a conservation plan if the plan could not be implemented entirely, was the main factor determining the relative performance of a flexibility enhanced approach to conservation prioritization. Our findings should help planning authorities prioritize conservation efforts in the face of uncertainty about future condition and availability of sites. © 2014 Society for Conservation Biology.

Vehicle Speed and Length Estimation Using Data from Two Anisotropic Magneto-Resistive (AMR) Sensors

PubMed Central

Markevicius, Vytautas; Navikas, Dangirutis; Valinevicius, Algimantas; Zilys, Mindaugas

2017-01-01

Methods for estimating a car’s length are presented in this paper, as well as the results achieved by using a self-designed system equipped with two anisotropic magneto-resistive (AMR) sensors, which were placed on a road lane. The purpose of the research was to compare the lengths of mid-size cars, i.e., family cars (hatchbacks), saloons (sedans), station wagons and SUVs. Four methods were used in the research: a simple threshold based method, a threshold method based on moving average and standard deviation, a two-extreme-peak detection method and a method based on the amplitude and time normalization using linear extrapolation (or interpolation). The results were achieved by analyzing changes in the magnitude and in the absolute z-component of the magnetic field as well. The tests, which were performed in four different Earth directions, show differences in the values of estimated lengths. The magnitude-based results in the case when cars drove from the South to the North direction were even up to 1.2 m higher than the other results achieved using the threshold methods. Smaller differences in lengths were observed when the distances were measured between two extreme peaks in the car magnetic signatures. The results were summarized in tables and the errors of estimated lengths were presented. The maximal errors, related to real lengths, were up to 22%. PMID:28771171

Hormonal Treatment of Transgender Women with Oral Estradiol.

PubMed

Leinung, Matthew C; Feustel, Paul J; Joseph, Jalaja

2018-01-01

Purpose: Maintaining cross-sex hormone levels in the normal physiologic range for the desired gender is the cornerstone of transgender hormonal therapy, but there are limited data on how to achieve this. We investigated the effectiveness of oral estradiol therapy in achieving this goal. Methods: We analyzed data on all transgender females seen in our clinic since 2008 treated with oral estradiol. We looked at the success of achieving serum levels of testosterone and 17-β estradiol in the normal range on various doses of estradiol (with and without antiandrogens spironolactone and finasteride). Results: There was a positive correlation between estradiol dose and 17-β estradiol, but testosterone suppression was less well correlated. Over 70% achieved treatment goals (adequate 17-β estradiol levels and testosterone suppression) on 4 mg daily or more. Nearly a third of patients did not achieve adequate treatment goals on 6 or even 8 mg daily of estradiol. Spironolactone, but not finasteride, use was associated with impairment of obtaining desired 17-β estradiol levels. Spironolactone did not enhance testosterone suppression, and finasteride was associated with higher testosterone levels. Conclusions: Oral estradiol was effective in achieving desired serum levels of 17-β estradiol, but there was wide individual variability in the amount required. Oral estradiol alone was not infrequently unable to achieve adequate testosterone suppression. Spironolactone did not aid testosterone suppression and seemed to impair achievement of goal serum 17-β estradiol levels. Testosterone levels were higher with finasteride use. We recommend that transgender women receiving estradiol therapy have hormone levels monitored so that therapy can be individualized.

Multiresolution generalized N dimension PCA for ultrasound image denoising

PubMed Central

2014-01-01

Background Ultrasound images are usually affected by speckle noise, which is a type of random multiplicative noise. Thus, reducing speckle and improving image visual quality are vital to obtaining better diagnosis. Method In this paper, a novel noise reduction method for medical ultrasound images, called multiresolution generalized N dimension PCA (MR-GND-PCA), is presented. In this method, the Gaussian pyramid and multiscale image stacks on each level are built first. GND-PCA as a multilinear subspace learning method is used for denoising. Each level is combined to achieve the final denoised image based on Laplacian pyramids. Results The proposed method is tested with synthetically speckled and real ultrasound images, and quality evaluation metrics, including MSE, SNR and PSNR, are used to evaluate its performance. Conclusion Experimental results show that the proposed method achieved the lowest noise interference and improved image quality by reducing noise and preserving the structure. Our method is also robust for the image with a much higher level of speckle noise. For clinical images, the results show that MR-GND-PCA can reduce speckle and preserve resolvable details. PMID:25096917

Emotional intelligence as a predictor of self-efficacy among students with different levels of academic achievement at Kermanshah University of Medical Sciences

PubMed Central

GHARETEPEH, AMENEH; SAFARI, YAHYA; PASHAEI, TAHEREH; RAZAEI, MANSOUR; BAGHER KAJBAF, MOHAMMAD

2015-01-01

Introduction studies have indicated that emotional intelligence is positively related to self-efficacy and can predict the academic achievement. The present study aimed to investigate the role of emotional intelligence in identifying self-efficacy among the students of Public Health School with different levels of academic achievement. Methods This correlational study was conducted on all the students of Public Health School. 129 students were included in the study through census method. Data were collected using Emotional Intelligence and self-efficacy questionnaires and analyzed using descriptive statistics and regression analysis by SPSS 14. Results The average score of students with high academic achievement was higher in self-efficacy (39.78±5.82) and emotional intelligence (117.07±10.33) variables and their components than that of students with low academic achievement (39.17±5.91, 112.07±13.23). The overall emotional intelligence score to predict self-efficacy explanation was different among students with different levels of academic achievement (p<0.001). Self-efficacy structure was explained through self-awareness and self-motivation components in students with low academic achievement (r=0.571). In students with high academic achievement, self-awareness, self-motivation and social consciousness played an effective role in explaining self-efficacy (r=0.677, p<0.001). Conclusion Emotional intelligence and self-efficacy play an important role in achieving academic success and emotional intelligence can explain self-efficacy. Therefore, it is recommended to teach emotional intelligence skills to students with low academic achievement through training workshops. PMID:25927067

A comparison of entropy balance and probability weighting methods to generalize observational cohorts to a population: a simulation and empirical example.

PubMed

Harvey, Raymond A; Hayden, Jennifer D; Kamble, Pravin S; Bouchard, Jonathan R; Huang, Joanna C

2017-04-01

We compared methods to control bias and confounding in observational studies including inverse probability weighting (IPW) and stabilized IPW (sIPW). These methods often require iteration and post-calibration to achieve covariate balance. In comparison, entropy balance (EB) optimizes covariate balance a priori by calibrating weights using the target's moments as constraints. We measured covariate balance empirically and by simulation by using absolute standardized mean difference (ASMD), absolute bias (AB), and root mean square error (RMSE), investigating two scenarios: the size of the observed (exposed) cohort exceeds the target (unexposed) cohort and vice versa. The empirical application weighted a commercial health plan cohort to a nationally representative National Health and Nutrition Examination Survey target on the same covariates and compared average total health care cost estimates across methods. Entropy balance alone achieved balance (ASMD ≤ 0.10) on all covariates in simulation and empirically. In simulation scenario I, EB achieved the lowest AB and RMSE (13.64, 31.19) compared with IPW (263.05, 263.99) and sIPW (319.91, 320.71). In scenario II, EB outperformed IPW and sIPW with smaller AB and RMSE. In scenarios I and II, EB achieved the lowest mean estimate difference from the simulated population outcome ($490.05, $487.62) compared with IPW and sIPW, respectively. Empirically, only EB differed from the unweighted mean cost indicating IPW, and sIPW weighting was ineffective. Entropy balance demonstrated the bias-variance tradeoff achieving higher estimate accuracy, yet lower estimate precision, compared with IPW methods. EB weighting required no post-processing and effectively mitigated observed bias and confounding. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

Pedagogical Models for Enhancing the Cross-Cultural Online Public Health Learning Environment

ERIC Educational Resources Information Center

Banerjee, Srikanta; Firtell, Jill

2017-01-01

Background: Online distance learning (e-learning) is an established method for providing higher education on a global scale due to its potential to reduce inequalities particularly in the area of public health education. Simultaneously, multicultural education is a key component of health education and can be achieved by fostering cultural…

Catalytic Assessment: Understanding How MCQs and EVS Can Foster Deep Learning

ERIC Educational Resources Information Center

Draper, Stephen W.

2009-01-01

One technology for education whose adoption is currently expanding rapidly in UK higher education is that of electronic voting systems (EVS). As with all educational technology, whether learning benefits are achieved depends not on the technology but on whether an improved teaching method is introduced with it. EVS inherently relies on the…

Teacher Reflective Practice in Jesuit High Schools

ERIC Educational Resources Information Center

Klug, Joseph H.

2010-01-01

Teachers who engage in reflective practice are more effective and may encourage higher student achievement. The purpose of this study is to explore and describe the methods that teachers use in order to engage in reflective practice. Further, it is essential to gain an understanding of how schools, including Jesuit high schools, promote reflective…

Maximizing Accessibility of Academic Publications: Applications of Electronic Publishing Technology

ERIC Educational Resources Information Center

Jeffress, Laura; Lyle, Stacey D.

2012-01-01

Professors at higher education institutions often feel pressure to "publish or perish" in order to maintain their standing in the academic community, yet a large number of these publications languish in obscure technical journals or are presented only once at a conference or online journal. While these methods achieve the goal of…

An Achievement Degree Analysis Approach to Identifying Learning Problems in Object-Oriented Programming

ERIC Educational Resources Information Center

Allinjawi, Arwa A.; Al-Nuaim, Hana A.; Krause, Paul

2014-01-01

Students often face difficulties while learning object-oriented programming (OOP) concepts. Many papers have presented various assessment methods for diagnosing learning problems to improve the teaching of programming in computer science (CS) higher education. The research presented in this article illustrates that although max-min composition is…

Readability Levels of Health-Based Websites: From Content to Comprehension

ERIC Educational Resources Information Center

Schutten, Mary; McFarland, Allison

2009-01-01

Three of the national health education standards include decision-making, accessing information and analyzing influences. WebQuests are a popular inquiry-oriented method used by secondary teachers to help students achieve these content standards. While WebQuests support higher level thinking skills, the readability level of the information on the…

Polyether/Polyester Graft Copolymers

NASA Technical Reports Server (NTRS)

Bell, Vernon L., Jr.; Wakelyn, N.; Stoakley, D. M.; Proctor, K. M.

1986-01-01

Higher solvent resistance achieved along with lower melting temperature. New technique provides method of preparing copolymers with polypivalolactone segments grafted onto poly (2,6-dimethyl-phenylene oxide) backbone. Process makes strong materials with improved solvent resistance and crystalline, thermally-reversible crosslinks. Resulting graft copolymers easier to fabricate into useful articles, including thin films, sheets, fibers, foams, laminates, and moldings.

Evaluating the Use of Criteria for Assessing Profession-Specific Communication Skills in Pharmacy

ERIC Educational Resources Information Center

Hyvarinen, Marja-Leena; Tanskanen, Paavo; Katajavuori, Nina; Isotalus, Pekka

2012-01-01

One central task in higher education is to provide students with interpersonal communication competence in their profession. To achieve this, specialised training, based on an understanding of disciplinary communication practices and appropriate assessment methods, is needed. However, there is a lack of reliable assessment instruments which are…

Improved Continuous-Time Higher Harmonic Control Using Hinfinity Methods

NASA Astrophysics Data System (ADS)

Fan, Frank H.

The helicopter is a versatile aircraft that can take-off and land vertically, hover efficiently, and maneuver in confined space. This versatility is enabled by the main rotor, which also causes undesired harmonic vibration during operation. This unwanted vibration has a negative impact on the practicality of the helicopter and also increases its operational cost. Passive control techniques have been applied to helicopter vibration suppression, but these methods are generally heavy and are not robust to changes in operating conditions. Feedback control offers the advantages of robustness and potentially higher performance over passive control techniques, and amongst the various feedback schemes, Shaw's higher harmonic control algorithm has been shown to be an effective method for attenuating harmonic disturbance in helicopters. In this thesis, the higher harmonic disturbance algorithm is further developed to achieve improved performance. One goal in this thesis is to determine the importance of periodicity in the helicopter rotor dynamics for control synthesis. Based on the analysis of wind tunnel data and simulation results, we conclude the helicopter rotor can be modeled reasonably well as linear and time-invariant for control design purposes. Modeling the helicopter rotor as linear time-invariant allows us to apply linear control theory concepts to the higher harmonic control problem. Another goal in this thesis is to find the limits of performance in harmonic disturbance rejection. To achieve this goal, we first define the metrics to measure the performance of the controller in terms of response speed and robustness to changes in the plant dynamics. The performance metrics are incorporated into an Hinfinity control problem. For a given plant, the resulting Hinfinity controller achieves the maximum performance, thus allowing us to identify the performance limitation in harmonic disturbance rejection. However, the Hinfinity controllers are of high order, and may have unstable poles, leading us to develop a design method to generate stable, fixed-order, and high performance controllers. Both the Hinfinity and the fixed-order controllers are designed for constant flight conditions. A gain-scheduled control law is used to reduce the vibration throughout the flight envelope. The gain-scheduling is accomplished by blending the outputs from fixed-order controllers designed for different flight conditions. The structure of the fixed-order controller allows the usage of a previously developed anti-windup scheme, and the blending function results in a bumpless full flight envelope control law. (Copies available exclusively from MIT Libraries, libraries.mit.edu/docs - docs mit.edu)

Classifying four-category visual objects using multiple ERP components in single-trial ERP.

PubMed

Qin, Yu; Zhan, Yu; Wang, Changming; Zhang, Jiacai; Yao, Li; Guo, Xiaojuan; Wu, Xia; Hu, Bin

2016-08-01

Object categorization using single-trial electroencephalography (EEG) data measured while participants view images has been studied intensively. In previous studies, multiple event-related potential (ERP) components (e.g., P1, N1, P2, and P3) were used to improve the performance of object categorization of visual stimuli. In this study, we introduce a novel method that uses multiple-kernel support vector machine to fuse multiple ERP component features. We investigate whether fusing the potential complementary information of different ERP components (e.g., P1, N1, P2a, and P2b) can improve the performance of four-category visual object classification in single-trial EEGs. We also compare the classification accuracy of different ERP component fusion methods. Our experimental results indicate that the classification accuracy increases through multiple ERP fusion. Additional comparative analyses indicate that the multiple-kernel fusion method can achieve a mean classification accuracy higher than 72 %, which is substantially better than that achieved with any single ERP component feature (55.07 % for the best single ERP component, N1). We compare the classification results with those of other fusion methods and determine that the accuracy of the multiple-kernel fusion method is 5.47, 4.06, and 16.90 % higher than those of feature concatenation, feature extraction, and decision fusion, respectively. Our study shows that our multiple-kernel fusion method outperforms other fusion methods and thus provides a means to improve the classification performance of single-trial ERPs in brain-computer interface research.

Simple, Rapid, and Selective Isolation of 2S Albumins from Allergenic Seeds and Nuts.

PubMed

Hummel, Marlene; Wigger, Tina; Höper, Tessa; Westkamp, Imke; Brockmeyer, Jens

2015-07-08

The 2S albumins belong to the group of seed storage proteins present in different seeds and nuts. Due to their pronounced allergenic potential, which is often associated with severe allergic reactions, this protein family is of special interest in the field of allergen research. Here we present a simple, rapid, and selective method for the purification of 2S albumins directly from allergenic seeds and nuts. We systematically optimized the parameters "buffer system", "extraction temperature", "buffer molarity", and "pH " and were able to achieve 2S albumin purities of about 99% without further purification and demonstrate transferability of this method to nine different allergenic food matrices. Compared to conventional isolation routines, significant reduction of hands-on time and required laboratory equipment is achieved, but nonetheless higher protein yields are obtained. The presented method allows for the rapid purification of different 2S albumins including the corresponding isoforms from natural material.

A fast and accurate frequency estimation algorithm for sinusoidal signal with harmonic components

NASA Astrophysics Data System (ADS)

Hu, Jinghua; Pan, Mengchun; Zeng, Zhidun; Hu, Jiafei; Chen, Dixiang; Tian, Wugang; Zhao, Jianqiang; Du, Qingfa

2016-10-01

Frequency estimation is a fundamental problem in many applications, such as traditional vibration measurement, power system supervision, and microelectromechanical system sensors control. In this paper, a fast and accurate frequency estimation algorithm is proposed to deal with low efficiency problem in traditional methods. The proposed algorithm consists of coarse and fine frequency estimation steps, and we demonstrate that it is more efficient than conventional searching methods to achieve coarse frequency estimation (location peak of FFT amplitude) by applying modified zero-crossing technique. Thus, the proposed estimation algorithm requires less hardware and software sources and can achieve even higher efficiency when the experimental data increase. Experimental results with modulated magnetic signal show that the root mean square error of frequency estimation is below 0.032 Hz with the proposed algorithm, which has lower computational complexity and better global performance than conventional frequency estimation methods.

Beam propagation modeling of modified volume Fresnel zone plates fabricated by femtosecond laser direct writing.

PubMed

Srisungsitthisunti, Pornsak; Ersoy, Okan K; Xu, Xianfan

2009-01-01

Light diffraction by volume Fresnel zone plates (VFZPs) is simulated by the Hankel transform beam propagation method (Hankel BPM). The method utilizes circularly symmetric geometry and small step propagation to calculate the diffracted wave fields by VFZP layers. It is shown that fast and accurate diffraction results can be obtained with the Hankel BPM. The results show an excellent agreement with the scalar diffraction theory and the experimental results. The numerical method allows more comprehensive studies of the VFZP parameters to achieve higher diffraction efficiency.

Energy-efficient ovens for unpolluted balady bread

DOE Office of Scientific and Technical Information (OSTI.GOV)

Gadalla, M.A.; Mansour, M.S.; Mahdy, E.

A new bread oven has been developed, tested and presented in this work for local balady bread. The design has the advantage of being efficient and producing unpolluted bread. An extensive study of the conventional and available designs has been carried out in order to help developing the new design. Evaluation of the conventional design is based on numerous tests and measurements. A computer code utilizing the indirect method has been developed to evaluate the thermal performance of the tested ovens. The present design achieves higher thermal efficiency of about 50% than the conventional ones. In addition, its capital costmore » is much cheaper than other imported designs. Thus, the present design achieves higher efficiency, pollutant free products and less cost. Moreover, it may be modified for different types of bread baking systems.« less

Time-optimal control with finite bandwidth

NASA Astrophysics Data System (ADS)

Hirose, M.; Cappellaro, P.

2018-04-01

Time-optimal control theory provides recipes to achieve quantum operations with high fidelity and speed, as required in quantum technologies such as quantum sensing and computation. While technical advances have achieved the ultrastrong driving regime in many physical systems, these capabilities have yet to be fully exploited for the precise control of quantum systems, as other limitations, such as the generation of higher harmonics or the finite response time of the control apparatus, prevent the implementation of theoretical time-optimal control. Here we present a method to achieve time-optimal control of qubit systems that can take advantage of fast driving beyond the rotating wave approximation. We exploit results from time-optimal control theory to design driving protocols that can be implemented with realistic, finite-bandwidth control fields, and we find a relationship between bandwidth limitations and achievable control fidelity.

Comparing student achievement in the problem-based learning classroom and traditional teaching methods classroom

NASA Astrophysics Data System (ADS)

Dobbs, Vicki

Significant numbers of students fail high school chemistry, preventing them from graduating. Starting in the 2013-2014 school year, 100% of the students must pass a science assessment for schools to meet Adequate Yearly Progress (AYP) in accordance to No Child Left Behind (NCLB). Failure to meet AYP results in sanctions, such as state management or closure of a school or replacing a school staff. The purpose of this study was to determine whether the teaching strategy, Problem Based Learning (PBL), will improve student achievement in high school chemistry to a greater degree than traditional teaching methods. PBL is a student-centered, inquiry-based teaching method based on the constructivist learning theory. The research question looked at whether there was a difference in student achievement between students a high school chemistry classroom using PBL and students in a classroom using traditional teaching methods as measured by scores on a 20-question quiz. The research study used a quasi-experimental pretest/posttest control group design. An independent samples t-test compared gains scores between the pretest and posttest. Analysis of quiz scores indicated that there was not a significant difference (t(171) = 1.001, p = .318) in student achievement between the teaching methods. Because there was not a significant difference, each teacher can decide which teaching method best suites the subject matter and the learning styles of the students. This study adds research based data to help teachers and schools choose one teaching method over another so that students may gain knowledge, develop problem-solving skills, and life-long learning skills that will bring about social change in the form of a higher quality of life for the students and community as a whole.

Numerical investigation of implementation of air-earth boundary by acoustic-elastic boundary approach

USGS Publications Warehouse

Xu, Y.; Xia, J.; Miller, R.D.

2007-01-01

The need for incorporating the traction-free condition at the air-earth boundary for finite-difference modeling of seismic wave propagation has been discussed widely. A new implementation has been developed for simulating elastic wave propagation in which the free-surface condition is replaced by an explicit acoustic-elastic boundary. Detailed comparisons of seismograms with different implementations for the air-earth boundary were undertaken using the (2,2) (the finite-difference operators are second order in time and space) and the (2,6) (second order in time and sixth order in space) standard staggered-grid (SSG) schemes. Methods used in these comparisons to define the air-earth boundary included the stress image method (SIM), the heterogeneous approach, the scheme of modifying material properties based on transversely isotropic medium approach, the acoustic-elastic boundary approach, and an analytical approach. The method proposed achieves the same or higher accuracy of modeled body waves relative to the SIM. Rayleigh waves calculated using the explicit acoustic-elastic boundary approach differ slightly from those calculated using the SIM. Numerical results indicate that when using the (2,2) SSG scheme for SIM and our new method, a spatial step of 16 points per minimum wavelength is sufficient to achieve 90% accuracy; 32 points per minimum wavelength achieves 95% accuracy in modeled Rayleigh waves. When using the (2,6) SSG scheme for the two methods, a spatial step of eight points per minimum wavelength achieves 95% accuracy in modeled Rayleigh waves. Our proposed method is physically reasonable and, based on dispersive analysis of simulated seismographs from a layered half-space model, is highly accurate. As a bonus, our proposed method is easy to program and slightly faster than the SIM. ?? 2007 Society of Exploration Geophysicists.

Evaluation of sampling methods for Bacillus spore-contaminated HVAC filters

PubMed Central

Calfee, M. Worth; Rose, Laura J.; Tufts, Jenia; Morse, Stephen; Clayton, Matt; Touati, Abderrahmane; Griffin-Gatchalian, Nicole; Slone, Christina; McSweeney, Neal

2016-01-01

The objective of this study was to compare an extraction-based sampling method to two vacuum-based sampling methods (vacuum sock and 37 mm cassette filter) with regards to their ability to recover Bacillus atrophaeus spores (surrogate for Bacillus anthracis) from pleated heating, ventilation, and air conditioning (HVAC) filters that are typically found in commercial and residential buildings. Electrostatic and mechanical HVAC filters were tested, both without and after loading with dust to 50% of their total holding capacity. The results were analyzed by one-way ANOVA across material types, presence or absence of dust, and sampling device. The extraction method gave higher relative recoveries than the two vacuum methods evaluated (p ≤ 0.001). On average, recoveries obtained by the vacuum methods were about 30% of those achieved by the extraction method. Relative recoveries between the two vacuum methods were not significantly different (p > 0.05). Although extraction methods yielded higher recoveries than vacuum methods, either HVAC filter sampling approach may provide a rapid and inexpensive mechanism for understanding the extent of contamination following a wide-area biological release incident. PMID:24184312

Evaluation of sampling methods for Bacillus spore-contaminated HVAC filters.

PubMed

Calfee, M Worth; Rose, Laura J; Tufts, Jenia; Morse, Stephen; Clayton, Matt; Touati, Abderrahmane; Griffin-Gatchalian, Nicole; Slone, Christina; McSweeney, Neal

2014-01-01

The objective of this study was to compare an extraction-based sampling method to two vacuum-based sampling methods (vacuum sock and 37mm cassette filter) with regards to their ability to recover Bacillus atrophaeus spores (surrogate for Bacillus anthracis) from pleated heating, ventilation, and air conditioning (HVAC) filters that are typically found in commercial and residential buildings. Electrostatic and mechanical HVAC filters were tested, both without and after loading with dust to 50% of their total holding capacity. The results were analyzed by one-way ANOVA across material types, presence or absence of dust, and sampling device. The extraction method gave higher relative recoveries than the two vacuum methods evaluated (p≤0.001). On average, recoveries obtained by the vacuum methods were about 30% of those achieved by the extraction method. Relative recoveries between the two vacuum methods were not significantly different (p>0.05). Although extraction methods yielded higher recoveries than vacuum methods, either HVAC filter sampling approach may provide a rapid and inexpensive mechanism for understanding the extent of contamination following a wide-area biological release incident. Published by Elsevier B.V.

Simplified dichromated gelatin hologram recording process

NASA Technical Reports Server (NTRS)

Georgekutty, Tharayil G.; Liu, Hua-Kuang

1987-01-01

A simplified method for making dichromated gelatin (DCG) holographic optical elements (HOE) has been discovered. The method is much less tedious and it requires a period of processing time comparable with that for processing a silver halide hologram. HOE characteristics including diffraction efficiency (DE), linearity, and spectral sensitivity have been quantitatively investigated. The quality of the holographic grating is very high. Ninety percent or higher diffraction efficiency has been achieved in simple plane gratings made by this process.

A path-based measurement for human miRNA functional similarities using miRNA-disease associations

NASA Astrophysics Data System (ADS)

Ding, Pingjian; Luo, Jiawei; Xiao, Qiu; Chen, Xiangtao

2016-09-01

Compared with the sequence and expression similarity, miRNA functional similarity is so important for biology researches and many applications such as miRNA clustering, miRNA function prediction, miRNA synergism identification and disease miRNA prioritization. However, the existing methods always utilized the predicted miRNA target which has high false positive and false negative to calculate the miRNA functional similarity. Meanwhile, it is difficult to achieve high reliability of miRNA functional similarity with miRNA-disease associations. Therefore, it is increasingly needed to improve the measurement of miRNA functional similarity. In this study, we develop a novel path-based calculation method of miRNA functional similarity based on miRNA-disease associations, called MFSP. Compared with other methods, our method obtains higher average functional similarity of intra-family and intra-cluster selected groups. Meanwhile, the lower average functional similarity of inter-family and inter-cluster miRNA pair is obtained. In addition, the smaller p-value is achieved, while applying Wilcoxon rank-sum test and Kruskal-Wallis test to different miRNA groups. The relationship between miRNA functional similarity and other information sources is exhibited. Furthermore, the constructed miRNA functional network based on MFSP is a scale-free and small-world network. Moreover, the higher AUC for miRNA-disease prediction indicates the ability of MFSP uncovering miRNA functional similarity.

Using Records of Achievement in Higher Education.

ERIC Educational Resources Information Center

Assiter, Alison, Ed.; Shaw, Eileen, Ed.

This collection of 22 essays examines the use of records of achievement (student profiles or portfolios) in higher and vocational education in the United Kingdom. They include: (1) "Records of Achievement: Background, Definitions, and Uses" (Alison Assiter and Eileen Shaw); (2) "Profiling in Higher Education" (Alison Assiter…

Modified rapid immunohistochemical staining for intraoperative diagnosis of malignant brain tumors.

PubMed

Suzuki, Akane; Maruyama, Takashi; Nitta, Masayuki; Komori, Takashi; Ikuta, Soko; Kawamata, Takakazu; Muragaki, Yoshihiro

2017-10-01

Rapid immunohistochemistry (R-IHC) has been developing mainly as a support technique in the rapid diagnosis of central nervous system tumors; however, there have been problems regarding instability in specimen preparation and immunostaining. To overcome the weakness of this technology, the instability of immunostaining, we developed a modified R-IHC. This was achieved by switching to 4% paraformaldehyde as the fixative solution and utilizing a commercially available Polymer Refine Detection Kit, as a high-sensitivity kit, in place of the secondary antibodies. In this study, we tested the modified R-IHC by evaluating rapid immunostaining on new staining items in 94 brain tumor removal cases, which took place at Tokyo Women's Medical University from 2014 to 2015. The results showed that, based on GFAP and p53 markers, the modified method obtained a higher stability in specimens than the standard rapid immunostaining method. It also achieved stainability on the same level as that of a permanent specimen. The modified method tested 86.6% (46/53) and 82.8% (24/29) in pHH3 and ATRX, respectively, in the percentage of correct classification (PCC) against the permanent specimens, and 100% (7/7) in the PCC against malignant lymphomas and gliomas that used CD20/CD3 for discrimination. We concluded that the modified R-IHC method indicated a higher stainability and PCC against the permanent specimens in comparison to the standard method in GFAP, p53, CD20/CD3, pHH3, and ATRX.

Efficient generation of integration-free human induced pluripotent stem cells from keratinocytes by simple transfection of episomal vectors.

PubMed

Piao, Yulan; Hung, Sandy Shen-Chi; Lim, Shiang Y; Wong, Raymond Ching-Bong; Ko, Minoru S H

2014-07-01

Keratinocytes represent an easily accessible cell source for derivation of human induced pluripotent stem (hiPS) cells, reportedly achieving higher reprogramming efficiency than fibroblasts. However, most studies utilized a retroviral or lentiviral method for reprogramming of keratinocytes, which introduces undesirable transgene integrations into the host genome. Moreover, current protocols of generating integration-free hiPS cells from keratinocytes are mostly inefficient. In this paper, we describe a more efficient, simple-to-use, and cost-effective method for generating integration-free hiPS cells from keratinocytes. Our improved method using lipid-mediated transfection achieved a reprogramming efficiency of ∼0.14% on average. Keratinocyte-derived hiPS cells showed no integration of episomal vectors, expressed stem cell-specific markers and possessed potentials to differentiate into all three germ layers by in vitro embryoid body formation as well as in vivo teratoma formation. To our knowledge, this represents the most efficient method to generate integration-free hiPS cells from keratinocytes. ©AlphaMed Press.

Application of the correlation constrained multivariate curve resolution alternating least-squares method for analyte quantitation in the presence of unexpected interferences using first-order instrumental data.

PubMed

Goicoechea, Héctor C; Olivieri, Alejandro C; Tauler, Romà

2010-03-01

Correlation constrained multivariate curve resolution-alternating least-squares is shown to be a feasible method for processing first-order instrumental data and achieve analyte quantitation in the presence of unexpected interferences. Both for simulated and experimental data sets, the proposed method could correctly retrieve the analyte and interference spectral profiles and perform accurate estimations of analyte concentrations in test samples. Since no information concerning the interferences was present in calibration samples, the proposed multivariate calibration approach including the correlation constraint facilitates the achievement of the so-called second-order advantage for the analyte of interest, which is known to be present for more complex higher-order richer instrumental data. The proposed method is tested using a simulated data set and two experimental data systems, one for the determination of ascorbic acid in powder juices using UV-visible absorption spectral data, and another for the determination of tetracycline in serum samples using fluorescence emission spectroscopy.

Color image segmentation with support vector machines: applications to road signs detection.

PubMed

Cyganek, Bogusław

2008-08-01

In this paper we propose efficient color segmentation method which is based on the Support Vector Machine classifier operating in a one-class mode. The method has been developed especially for the road signs recognition system, although it can be used in other applications. The main advantage of the proposed method comes from the fact that the segmentation of characteristic colors is performed not in the original but in the higher dimensional feature space. By this a better data encapsulation with a linear hypersphere can be usually achieved. Moreover, the classifier does not try to capture the whole distribution of the input data which is often difficult to achieve. Instead, the characteristic data samples, called support vectors, are selected which allow construction of the tightest hypersphere that encloses majority of the input data. Then classification of a test data simply consists in a measurement of its distance to a centre of the found hypersphere. The experimental results show high accuracy and speed of the proposed method.

3D Higher Order Modeling in the BEM/FEM Hybrid Formulation

NASA Technical Reports Server (NTRS)

Fink, P. W.; Wilton, D. R.

2000-01-01

Higher order divergence- and curl-conforming bases have been shown to provide significant benefits, in both convergence rate and accuracy, in the 2D hybrid finite element/boundary element formulation (P. Fink and D. Wilton, National Radio Science Meeting, Boulder, CO, Jan. 2000). A critical issue in achieving the potential for accuracy of the approach is the accurate evaluation of all matrix elements. These involve products of high order polynomials and, in some instances, singular Green's functions. In the 2D formulation, the use of a generalized Gaussian quadrature method was found to greatly facilitate the computation and to improve the accuracy of the boundary integral equation self-terms. In this paper, a 3D, hybrid electric field formulation employing higher order bases and higher order elements is presented. The improvements in convergence rate and accuracy, compared to those resulting from lower order modeling, are established. Techniques developed to facilitate the computation of the boundary integral self-terms are also shown to improve the accuracy of these terms. Finally, simple preconditioning techniques are used in conjunction with iterative solution procedures to solve the resulting linear system efficiently. In order to handle the boundary integral singularities in the 3D formulation, the parent element- either a triangle or rectangle-is subdivided into a set of sub-triangles with a common vertex at the singularity. The contribution to the integral from each of the sub-triangles is computed using the Duffy transformation to remove the singularity. This method is shown to greatly facilitate t'pe self-term computation when the bases are of higher order. In addition, the sub-triangles can be further divided to achieve near arbitrary accuracy in the self-term computation. An efficient method for subdividing the parent element is presented. The accuracy obtained using higher order bases is compared to that obtained using lower order bases when the number of unknowns is approximately equal. Also, convergence rates obtained using higher order bases are compared to those obtained with lower order bases for selected sample

Luma-chroma space filter design for subpixel-based monochrome image downsampling.

PubMed

Fang, Lu; Au, Oscar C; Cheung, Ngai-Man; Katsaggelos, Aggelos K; Li, Houqiang; Zou, Feng

2013-10-01

In general, subpixel-based downsampling can achieve higher apparent resolution of the down-sampled images on LCD or OLED displays than pixel-based downsampling. With the frequency domain analysis of subpixel-based downsampling, we discover special characteristics of the luma-chroma color transform choice for monochrome images. With these, we model the anti-aliasing filter design for subpixel-based monochrome image downsampling as a human visual system-based optimization problem with a two-term cost function and obtain a closed-form solution. One cost term measures the luminance distortion and the other term measures the chrominance aliasing in our chosen luma-chroma space. Simulation results suggest that the proposed method can achieve sharper down-sampled gray/font images compared with conventional pixel and subpixel-based methods, without noticeable color fringing artifacts.

Study of The Vector Product using Three Dimensions Vector Card of Engineering in Pathumwan Institute of Technology

NASA Astrophysics Data System (ADS)

Mueanploy, Wannapa

2015-06-01

The objective of this research was to offer the way to improve engineering students in Physics topic of vector product. The sampling of this research was the engineering students at Pathumwan Institute of Technology during the first semester of academic year 2013. 1) Select 120 students by random sampling are asked to fill in a satisfaction questionnaire scale, to select size of three dimensions vector card in order to apply in the classroom. 2) Select 60 students by random sampling to do achievement test and take the test to be used in the classroom. The methods used in analysis of achievement test by the Kuder-Richardson Method (KR- 20). The results show that 12 items of achievement test are appropriate to be applied in the classroom. The achievement test gets Difficulty (P) = 0.40-0.67, Discrimination = 0.33-0.73 and Reliability (r) = 0.70.The experimental in the classroom. 3) Select 60 students by random sampling divide into two groups; group one (the controlled group) with 30 students was chosen to study in the vector product lesson by the regular teaching method. Group two (the experimental group) with 30 students was chosen to learn the vector product lesson with three dimensions vector card. 4) Analyzed data between the controlled group and the experimental group, the result showed that experimental group got higher achievement test than the controlled group significant at .01 level.

Reading and math achievement profiles and longitudinal growth trajectories of children with an autism spectrum disorder.

PubMed

Wei, Xin; Christiano, Elizabeth R A; Yu, Jennifer W; Wagner, Mary; Spiker, Donna

2015-02-01

This study examined the reading and math achievement profiles and longitudinal growth trajectories of a nationally representative sample of children ages 6 through 9 with an autism spectrum disorder. Four distinct achievement profiles were identified: higher-achieving (39%), hyperlexia (9%), hypercalculia (20%) and lower-achieving (32%). Children with hypercalculia and lower-achieving profiles were more likely to be from low socioeconomic families and had lower functional cognitive skills than the higher-achieving profile. All four profiles lost ground in passage comprehension over time. Slower improvement occurred for the higher-achieving group on letter-word identification, the hyperlexia group on conversation abilities and the hypercalculia group on calculation and functional cognitive skills relative to the lower-achieving group. © The Author(s) 2014.

Differential solubility of curcuminoids in serum and albumin solutions: implications for analytical and therapeutic applications

PubMed Central

Quitschke, Wolfgang W

2008-01-01

Background Commercially available curcumin preparations contain a mixture of related polyphenols, collectively referred to as curcuminoids. These encompass the primary component curcumin along with its co-purified derivatives demethoxycurcumin and bisdemethoxycurcumin. Curcuminoids have numerous biological activities, including inhibition of cancer related cell proliferation and reduction of amyloid plaque formation associated with Alzheimer disease. Unfortunately, the solubility of curcuminoids in aqueous solutions is exceedingly low. This restricts their systemic availability in orally administered formulations and limits their therapeutic potential. Results Methods are described that achieve high concentrations of soluble curcuminoids in serum. Solid curcuminoids were either mixed directly with serum, or they were predissolved in dimethyl sulfoxide and added as aliquots to serum. Both methods resulted in high levels of curcuminoid-solubility in mammalian sera from different species. However, adding aliquots of dimethyl sulfoxide-dissolved curcuminoids to serum proved to be more efficient, producing soluble curcuminoid concentrations of at least 3 mM in human serum. The methods also resulted in the differential solubility of individual curcuminoids in serum. The addition of dimethyl sulfoxide-dissolved curcuminoids to serum preferentially solubilized curcumin, whereas adding solid curcuminoids predominantly solubilized bisdemethoxycurcumin. Either method of solubilization was equally effective in inhibiting dose-dependent HeLa cell proliferation in culture. The maximum concentration of curcuminoids achieved in serum was at least 100-fold higher than that required for inhibiting cell proliferation in culture and 1000-fold higher than the concentration that has been reported to prevent amyloid plaque formation associated with Alzheimer disease. Curcuminoids were also highly soluble in solutions of purified albumin, a major component of serum. Conclusion These results suggest the possibility of alternative therapeutic approaches by injection or infusion of relatively small amounts of curcuminoid-enriched serum. They also provide tools to reproducibly solubilize curcuminoids for analysis in cell culture applications. The differential solubility of curcuminoids achieved by different methods of solubilization offers convenient alternatives to assess the diverse biological effects contributed by curcumin and its derivatives. PMID:18990234

Design and performance of tapered cubic anvil used for achieving higher pressure and larger sample cell

NASA Astrophysics Data System (ADS)

Han, Qi-Gang; Yang, Wen-Ke; Zhu, Pin-Wen; Ban, Qing-Chu; Yan, Ni; Zhang, Qiang

2013-07-01

In order to increase the maximum cell pressure of the cubic high pressure apparatus, we have developed a new structure of tungsten carbide cubic anvil (tapered cubic anvil), based on the principle of massive support and lateral support. Our results indicated that the tapered cubic anvil has some advantages. First, tapered cubic anvil can push the transfer rate of pressure well into the range above 36.37% compare to the conventional anvil. Second, the rate of failure crack decreases about 11.20% after the modification of the conventional anvil. Third, the limit of static high-pressure in the sample cell can be extended to 13 GPa, which can increase the maximum cell pressure about 73.3% than that of the conventional anvil. Fourth, the volume of sample cell compressed by tapered cubic anvils can be achieved to 14.13 mm3 (3 mm diameter × 2 mm long), which is three and six orders of magnitude larger than that of double-stage apparatus and diamond anvil cell, respectively. This work represents a relatively simple method for achieving higher pressures and larger sample cell.

Measuring Achievement Goal Orientations of Pharmacy Students

PubMed Central

Muthart, Thomas; Khan, Ghous M.

2014-01-01

Objectives. To measure the achievement goal orientations of pharmacy students attending a 3-year (accelerated) doctor of pharmacy (PharmD) program. Methods. A 16-item survey based on the Achievement Goal Questionnaire (AGQ) was administered to first-year (P1) and second-year (P2) pharmacy students at the Appalachian College of Pharmacy (ACP). Students were instructed to indicate to what degree each statement was true for them using a 7-point Likert scale (1=not true of me, 7=very true of me). Results. One hundred twenty of the 155 students (77%) completed the survey. Most students had mastery-approach, mastery-avoidance, performance-approach, and/or performance-avoidance goal orientations; few had work-avoidance goal orientations. Second-year students and male students had higher work-avoidance mean scores than did P1 students and female students (p<0.05). Conclusion. Pharmacy students were mastery- and performance-oriented learners, and most did not have work-avoidance goal orientations. Male students and P2 students had higher work-avoidance than did female students and P1 students, respectively. More longitudinal studies are needed to confirm these findings. PMID:24761015

Gamification in science education: The relationship of educational games to motivation and achievement

NASA Astrophysics Data System (ADS)

Rouse, Kelly Elizabeth

Community colleges have become increasingly more important in America's higher education system. Part of this emphasis has been directly due to President Obama's 2010 directive to produce a competitive workforce in the United States by increasing the community college graduation rate by five million over the next decade (Madhani, 2010). Community colleges allow open admission for students which permits marginally prepared students to enter. These students may lack motivation, which contributes to student attrition (Williams, 2010). The focus of this study is to examine methods that may improve student learning and motivation, which could ultimately lead to higher graduation rates. This study investigates the relationship of gamification to motivation and achievement in a community college microbiology class. Gamification is defined as "the process of adding game mechanics to processes, programs, and platforms that would not traditionally use such concepts" (Swan, 2012). The goal of game-based learning is to increase student motivation and learning. The results of this investigation indicate that educational games increase motivation and achievement of students in a community college microbiology class.

Teaching Quality in Math Class: The Development of a Scale and the Analysis of Its Relationship with Engagement and Achievement

PubMed Central

Leon, Jaime; Medina-Garrido, Elena; Núñez, Juan L.

2017-01-01

Math achievement and engagement declines in secondary education; therefore, educators are faced with the challenge of engaging students to avoid school failure. Within self-determination theory, we address the need to assess comprehensively student perceptions of teaching quality that predict engagement and achievement. In study one we tested, in a sample of 548 high school students, a preliminary version of a scale to assess nine factors: teaching for relevance, acknowledge negative feelings, participation encouragement, controlling language, optimal challenge, focus on the process, class structure, positive feedback, and caring. In the second study, we analyzed the scale’s reliability and validity in a sample of 1555 high school students. The scale showed evidence of reliability, and with regard to criterion validity, at the classroom level, teaching quality was a predictor of behavioral engagement, and higher grades were observed in classes where students, as a whole, displayed more behavioral engagement. At the within level, behavioral engagement was associated with achievement. We not only provide a reliable and valid method to assess teaching quality, but also a method to design interventions, these could be designed based on the scale items to encourage students to persist and display more engagement on school duties, which in turn bolsters student achievement. PMID:28701964

Teaching Quality in Math Class: The Development of a Scale and the Analysis of Its Relationship with Engagement and Achievement.

PubMed

Leon, Jaime; Medina-Garrido, Elena; Núñez, Juan L

2017-01-01

Math achievement and engagement declines in secondary education; therefore, educators are faced with the challenge of engaging students to avoid school failure. Within self-determination theory, we address the need to assess comprehensively student perceptions of teaching quality that predict engagement and achievement. In study one we tested, in a sample of 548 high school students, a preliminary version of a scale to assess nine factors: teaching for relevance, acknowledge negative feelings, participation encouragement, controlling language, optimal challenge, focus on the process, class structure, positive feedback, and caring. In the second study, we analyzed the scale's reliability and validity in a sample of 1555 high school students. The scale showed evidence of reliability, and with regard to criterion validity, at the classroom level, teaching quality was a predictor of behavioral engagement, and higher grades were observed in classes where students, as a whole, displayed more behavioral engagement. At the within level, behavioral engagement was associated with achievement. We not only provide a reliable and valid method to assess teaching quality, but also a method to design interventions, these could be designed based on the scale items to encourage students to persist and display more engagement on school duties, which in turn bolsters student achievement.

Single-cell genomics for the masses

DOE Office of Scientific and Technical Information (OSTI.GOV)

Tringe, Susannah G.

In this issue of Nature Biotechnology, Lan et al. describe a new tool in the toolkit for studying uncultivated microbial communities, enabling orders of magnitude higher single cell genome throughput than previous methods. This is achieved by a complex droplet microfluidics workflow encompassing steps from physical cell isolation through genome sequencing, producing tens of thousands of lowcoverage genomes from individual cells.

Single-cell genomics for the masses

DOE PAGES

Tringe, Susannah G.

2017-07-12

In this issue of Nature Biotechnology, Lan et al. describe a new tool in the toolkit for studying uncultivated microbial communities, enabling orders of magnitude higher single cell genome throughput than previous methods. This is achieved by a complex droplet microfluidics workflow encompassing steps from physical cell isolation through genome sequencing, producing tens of thousands of lowcoverage genomes from individual cells.

E-Portfolio Assessment: A Mixed Methods Study of an Instructional Leadership Program's Assessment System

ERIC Educational Resources Information Center

Hardin, James; Wright, Vivian H.

2017-01-01

Institutions of higher education face demands to provide evidence of institutional and student achievement. Many institutions utilize standards-based e-portfolio assessment practices to meet these demands. The assessment data derived from the studied program's e-portfolio process were not originally intended to serve as a data source for…

Validating the Persian Version of Reflective Thinking Questionnaire and Probing Iranian University Students' Reflective Thinking and Academic Achievement

ERIC Educational Resources Information Center

Ghanizadeh, Afsaneh; Jahedizadeh, Safoura

2017-01-01

Scholars in higher education deem reflective thinking as integral to the development of professional disciplinary practices. One of the major issues in studying reflective thinking pivots around its conceptualization and assessment. Over the years, researchers have used several methods and scales to measure reflective thinking. One of the most…

The Structure of Research Methodology Competency in Higher Education and the Role of Teaching Teams and Course Temporal Distance

ERIC Educational Resources Information Center

Schweizer, Karl; Steinwascher, Merle; Moosbrugger, Helfried; Reiss, Siegbert

2011-01-01

The development of research methodology competency is a major aim of the psychology curriculum at universities. Usually, three courses concentrating on basic statistics, advanced statistics and experimental methods, respectively, serve the achievement of this aim. However, this traditional curriculum-based course structure gives rise to the…

Mind and Material: The Interplay between Computer-Related and Second Language Factors in Online Communication Dialogues

ERIC Educational Resources Information Center

Wu, Pin-hsiang Natalie; Kawamura, Michelle

2014-01-01

With a growing demand for learning English and a trend of utilizing computers in education, methods that can achieve the effectiveness of computer-mediated communication (CMC) to support language learning in higher education have been examined. However, second language factors manipulate both the process and production of CMC and, therefore,…

Demystifying the Lens of Color: Examining the Relationship between Academic Achievement and Racial Identity

ERIC Educational Resources Information Center

Wyche-Hall, Marla E.

2011-01-01

The purpose of this mixed methods research study was to examine the dynamic interaction between the racial and academic identities of African American, undergraduate students who were enrolled full time at an academic institution of higher education that was both a Hispanic-serving institution (HSI), and a predominately White institution (PWI).…

Term-Time Employment and the Academic Performance of Undergraduates

ERIC Educational Resources Information Center

Wenz, Michael; Yu, Wei-Choun

2010-01-01

This article outlines a framework for evaluating the decision of undergraduate students to engage in term-time employment as a method of financing higher education. We then examine the impact of work on academic achievement and find that employment has modest negative effects on student grades, with a grade point average (GPA) falling by 0.007…

System safety education focused on flight safety

NASA Technical Reports Server (NTRS)

Holt, E.

1971-01-01

The measures necessary for achieving higher levels of system safety are analyzed with an eye toward maintaining the combat capability of the Air Force. Several education courses were provided for personnel involved in safety management. Data include: (1) Flight Safety Officer Course, (2) Advanced Safety Program Management, (3) Fundamentals of System Safety, and (4) Quantitative Methods of Safety Analysis.

Robust path planning for flexible needle insertion using Markov decision processes.

PubMed

Tan, Xiaoyu; Yu, Pengqian; Lim, Kah-Bin; Chui, Chee-Kong

2018-05-11

Flexible needle has the potential to accurately navigate to a treatment region in the least invasive manner. We propose a new planning method using Markov decision processes (MDPs) for flexible needle navigation that can perform robust path planning and steering under the circumstance of complex tissue-needle interactions. This method enhances the robustness of flexible needle steering from three different perspectives. First, the method considers the problem caused by soft tissue deformation. The method then resolves the common needle penetration failure caused by patterns of targets, while the last solution addresses the uncertainty issues in flexible needle motion due to complex and unpredictable tissue-needle interaction. Computer simulation and phantom experimental results show that the proposed method can perform robust planning and generate a secure control policy for flexible needle steering. Compared with a traditional method using MDPs, the proposed method achieves higher accuracy and probability of success in avoiding obstacles under complicated and uncertain tissue-needle interactions. Future work will involve experiment with biological tissue in vivo. The proposed robust path planning method can securely steer flexible needle within soft phantom tissues and achieve high adaptability in computer simulation.

Palmprint authentication using multiple classifiers

NASA Astrophysics Data System (ADS)

Kumar, Ajay; Zhang, David

2004-08-01

This paper investigates the performance improvement for palmprint authentication using multiple classifiers. The proposed methods on personal authentication using palmprints can be divided into three categories; appearance- , line -, and texture-based. A combination of these approaches can be used to achieve higher performance. We propose to simultaneously extract palmprint features from PCA, Line detectors and Gabor-filters and combine their corresponding matching scores. This paper also investigates the comparative performance of simple combination rules and the hybrid fusion strategy to achieve performance improvement. Our experimental results on the database of 100 users demonstrate the usefulness of such approach over those based on individual classifiers.

Structure guided GANs

NASA Astrophysics Data System (ADS)

Cao, Feidao; Zhao, Huaici; Liu, Pengfei

2017-11-01

Generative adversarial networks (GANs) has achieved success in many fields. However, there are some samples generated by many GAN-based works, whose structure is ambiguous. In this work, we propose Structure Guided GANs that introduce structural similar into GANs to overcome the problem. In order to achieve our goal, we introduce an encoder and a decoder into a generator to design a new generator and take real samples as part of the input of a generator. And we modify the loss function of the generator accordingly. By comparison with WGAN, experimental results show that our proposed method overcomes largely sample structure ambiguous and can generate higher quality samples.

Determination of α-tocopherol by reversed-phase HPLC in feed and animal-derived foods without saponification.

PubMed

Claeys, Erik; Vossen, Els; De Smet, Stefaan

2016-01-30

The analysis of α-tocopherol in feed and animal-derived foods usually involves a saponification step. However, since saponification often leads to losses of α-tocopherol, a method for the determination of α-tocopherol in feed and in animal-derived foods was developed without a saponification step. In this method, α-tocopherol is extracted with hot ethanol and the co-extracted fat is removed by centrifugation. Removal of the fat fraction is made possible by the addition of water, to achieve an ethanol:water ratio of 40:7, followed by cooling on ice before centrifugation. This procedure allows removal of the fat fraction, while α-tocopherol is retained. Matrices differing in gross composition and α-tocopherol content were analyzed: fresh pork, cooked ham, subcutaneous fat, liver, egg yolk, milk and a compound pig feed. Higher α-tocopherol concentrations were found for this novel method compared to a conventional method with saponification, particularly for subcutaneous fat (P < 0.05). Recoveries were higher (P < 0.05) for the novel method (82-103%), compared to the saponification method (66-90%; for subcutaneous fat < 25%). Determining α-tocopherol in feed and animal-derived foods using pure ethanol without saponification results in higher extraction yields and recoveries compared to the saponification method. © 2015 Society of Chemical Industry.

Consensus Algorithms for Networks of Systems with Second- and Higher-Order Dynamics

NASA Astrophysics Data System (ADS)

Fruhnert, Michael

This thesis considers homogeneous networks of linear systems. We consider linear feedback controllers and require that the directed graph associated with the network contains a spanning tree and systems are stabilizable. We show that, in continuous-time, consensus with a guaranteed rate of convergence can always be achieved using linear state feedback. For networks of continuous-time second-order systems, we provide a new and simple derivation of the conditions for a second-order polynomials with complex coefficients to be Hurwitz. We apply this result to obtain necessary and sufficient conditions to achieve consensus with networks whose graph Laplacian matrix may have complex eigenvalues. Based on the conditions found, methods to compute feedback gains are proposed. We show that gains can be chosen such that consensus is achieved robustly over a variety of communication structures and system dynamics. We also consider the use of static output feedback. For networks of discrete-time second-order systems, we provide a new and simple derivation of the conditions for a second-order polynomials with complex coefficients to be Schur. We apply this result to obtain necessary and sufficient conditions to achieve consensus with networks whose graph Laplacian matrix may have complex eigenvalues. We show that consensus can always be achieved for marginally stable systems and discretized systems. Simple conditions for consensus achieving controllers are obtained when the Laplacian eigenvalues are all real. For networks of continuous-time time-variant higher-order systems, we show that uniform consensus can always be achieved if systems are quadratically stabilizable. In this case, we provide a simple condition to obtain a linear feedback control. For networks of discrete-time higher-order systems, we show that constant gains can be chosen such that consensus is achieved for a variety of network topologies. First, we develop simple results for networks of time-invariant systems and networks of time-variant systems that are given in controllable canonical form. Second, we formulate the problem in terms of Linear Matrix Inequalities (LMIs). The condition found simplifies the design process and avoids the parallel solution of multiple LMIs. The result yields a modified Algebraic Riccati Equation (ARE) for which we present an equivalent LMI condition.

Training set extension for SVM ensemble in P300-speller with familiar face paradigm.

PubMed

Li, Qi; Shi, Kaiyang; Gao, Ning; Li, Jian; Bai, Ou

2018-03-27

P300-spellers are brain-computer interface (BCI)-based character input systems. Support vector machine (SVM) ensembles are trained with large-scale training sets and used as classifiers in these systems. However, the required large-scale training data necessitate a prolonged collection time for each subject, which results in data collected toward the end of the period being contaminated by the subject's fatigue. This study aimed to develop a method for acquiring more training data based on a collected small training set. A new method was developed in which two corresponding training datasets in two sequences are superposed and averaged to extend the training set. The proposed method was tested offline on a P300-speller with the familiar face paradigm. The SVM ensemble with extended training set achieved 85% classification accuracy for the averaged results of four sequences, and 100% for 11 sequences in the P300-speller. In contrast, the conventional SVM ensemble with non-extended training set achieved only 65% accuracy for four sequences, and 92% for 11 sequences. The SVM ensemble with extended training set achieves higher classification accuracies than the conventional SVM ensemble, which verifies that the proposed method effectively improves the classification performance of BCI P300-spellers, thus enhancing their practicality.

WWC Review of the Report "Staying on Track: Testing Higher Achievement's Long-Term Impact on Academic Outcomes and High School Choice." What Works Clearinghouse Single Study Review

ERIC Educational Resources Information Center

What Works Clearinghouse, 2014

2014-01-01

This study of 952 fifth and sixth graders in Washington, DC, and Alexandria, Virginia, found that students who were offered the "Higher Achievement" program had higher test scores in mathematical problem solving and were more likely to be admitted to and attend private competitive high schools. "Higher Achievement" is a…

Silicon ribbon growth by a capillary action shaping technique

NASA Technical Reports Server (NTRS)

Schwuttke, G. H.; Ciszek, T. F.; Kran, A.; Yang, K.

1977-01-01

The crystal-growth method under investigation is a capillary action shaping technique. Meniscus shaping for the desired ribbon geometry occurs at the vertex of a wettable dye. As ribbon growth depletes the melt meniscus, capillary action supplies replacement material. The configuration of the technique used in our initial studies is shown. The crystal-growth method has been applied to silicon ribbons it was found that substantial improvements in ribbon surface quality could be achieved with a higher melt meniscus than that attainable with the EFG technique.

Development of a Compound Optimization Approach Based on Imperialist Competitive Algorithm

NASA Astrophysics Data System (ADS)

Wang, Qimei; Yang, Zhihong; Wang, Yong

In this paper, an improved novel approach is developed for the imperialist competitive algorithm to achieve a greater performance. The Nelder-Meand simplex method is applied to execute alternately with the original procedures of the algorithm. The approach is tested on twelve widely-used benchmark functions and is also compared with other relative studies. It is shown that the proposed approach has a faster convergence rate, better search ability, and higher stability than the original algorithm and other relative methods.

Designing scalable product families by the radial basis function-high-dimensional model representation metamodelling technique

NASA Astrophysics Data System (ADS)

Pirmoradi, Zhila; Haji Hajikolaei, Kambiz; Wang, G. Gary

2015-10-01

Product family design is cost-efficient for achieving the best trade-off between commonalization and diversification. However, for computationally intensive design functions which are viewed as black boxes, the family design would be challenging. A two-stage platform configuration method with generalized commonality is proposed for a scale-based family with unknown platform configuration. Unconventional sensitivity analysis and information on variation in the individual variants' optimal design are used for platform configuration design. Metamodelling is employed to provide the sensitivity and variable correlation information, leading to significant savings in function calls. A family of universal electric motors is designed for product performance and the efficiency of this method is studied. The impact of the employed parameters is also analysed. Then, the proposed method is modified for obtaining higher commonality. The proposed method is shown to yield design solutions with better objective function values, allowable performance loss and higher commonality than the previously developed methods in the literature.

A MUSIC-based method for SSVEP signal processing.

PubMed

Chen, Kun; Liu, Quan; Ai, Qingsong; Zhou, Zude; Xie, Sheng Quan; Meng, Wei

2016-03-01

The research on brain computer interfaces (BCIs) has become a hotspot in recent years because it offers benefit to disabled people to communicate with the outside world. Steady state visual evoked potential (SSVEP)-based BCIs are more widely used because of higher signal to noise ratio and greater information transfer rate compared with other BCI techniques. In this paper, a multiple signal classification based method was proposed for multi-dimensional SSVEP feature extraction. 2-second data epochs from four electrodes achieved excellent accuracy rates including idle state detection. In some asynchronous mode experiments, the recognition accuracy reached up to 100%. The experimental results showed that the proposed method attained good frequency resolution. In most situations, the recognition accuracy was higher than canonical correlation analysis, which is a typical method for multi-channel SSVEP signal processing. Also, a virtual keyboard was successfully controlled by different subjects in an unshielded environment, which proved the feasibility of the proposed method for multi-dimensional SSVEP signal processing in practical applications.

A new integrated evaluation method of heavy metals pollution control during melting and sintering of MSWI fly ash.

PubMed

Li, Rundong; Li, Yanlong; Yang, Tianhua; Wang, Lei; Wang, Weiyun

2015-05-30

Evaluations of technologies for heavy metal control mainly examine the residual and leaching rates of a single heavy metal, such that developed evaluation method have no coordination or uniqueness and are therefore unsuitable for hazard control effect evaluation. An overall pollution toxicity index (OPTI) was established in this paper, based on the developed index, an integrated evaluation method of heavy metal pollution control was established. Application of this method in the melting and sintering of fly ash revealed the following results: The integrated control efficiency of the melting process was higher in all instances than that of the sintering process. The lowest integrated control efficiency of melting was 56.2%, and the highest integrated control efficiency of sintering was 46.6%. Using the same technology, higher integrated control efficiency conditions were all achieved with lower temperatures and shorter times. This study demonstrated the unification and consistency of this method. Copyright © 2015 Elsevier B.V. All rights reserved.

Time-varying higher order spectra

NASA Astrophysics Data System (ADS)

Boashash, Boualem; O'Shea, Peter

1991-12-01

A general solution for the problem of time-frequency signal representation of nonlinear FM signals is provided, based on a generalization of the Wigner-Ville distribution. The Wigner- Ville distribution (WVD) is a second order time-frequency representation. That is, it is able to give ideal energy concentration for quadratic phase signals and its ensemble average is a second order time-varying spectrum. The same holds for Cohen's class of time-frequency distributions, which are smoothed versions of the WVD. The WVD may be extended so as to achieve ideal energy concentration for higher order phase laws, and such that the expectation is a time-varying higher order spectrum. The usefulness of these generalized Wigner-Ville distributions (GWVD) is twofold. Firstly, because they achieve ideal energy concentration for polynomial phase signals, they may be used for optimal instantaneous frequency estimation. Second, they are useful for discriminating between nonstationary processes of differing higher order moments. In the same way that the WVD is generalized, we generalize Cohen's class of TFDs by defining a class of generalized time-frequency distributions (GTFDs) obtained by a two dimensional smoothing of the GWVD. Another results derived from this approach is a method based on higher order spectra which allows the separation of cross-terms and auto- terms in the WVD.

Developing students’ learning achievement and experimental skills on buoyancy and the involvement of Newton’s third law through experimental sets

NASA Astrophysics Data System (ADS)

Chokchai, Jaewijarn; Khanti, Toedtanya; Sura, Wuttiprom

2017-09-01

The purposes of this research were: to construct packages of operations on buoyancy and the involvement of Newton’s third law, to enhance achievement score of students on buoyancy and the involvement of Newton’s third law, to enhance experimental skills on buoyancy and the involvement of Newton’s third law and to evaluate students’ attitude towards the packages of operations on buoyancy and the involvement of Newton’s third law using inquiry method. The samples were 42 grade 11 students in academic year 2016 at Hatyaiwittayalai School, Hatyai, Songkhla. The research method was one group pretest-posttest design. The research tools consisted of experimental set on buoyancy and the involvement of Newton’s third law, the learning achievement test on buoyancy and the involvement of Newton’s third law and the students’ attitude questionnaires. The experimental skills of most students was in a good level . The satisfaction of most students was in a good level. The research showed the learning achievement after instruction higher than that before instruction using experimental set at the significant level of 0.05 and the class average normalized gain is in the medium gain

Wideband optical sensing using pulse interferometry.

PubMed

Rosenthal, Amir; Razansky, Daniel; Ntziachristos, Vasilis

2012-08-13

Advances in fabrication of high-finesse optical resonators hold promise for the development of miniaturized, ultra-sensitive, wide-band optical sensors, based on resonance-shift detection. Many potential applications are foreseen for such sensors, among them highly sensitive detection in ultrasound and optoacoustic imaging. Traditionally, sensor interrogation is performed by tuning a narrow linewidth laser to the resonance wavelength. Despite the ubiquity of this method, its use has been mostly limited to lab conditions due to its vulnerability to environmental factors and the difficulty of multiplexing - a key factor in imaging applications. In this paper, we develop a new optical-resonator interrogation scheme based on wideband pulse interferometry, potentially capable of achieving high stability against environmental conditions without compromising sensitivity. Additionally, the method can enable multiplexing several sensors. The unique properties of the pulse-interferometry interrogation approach are studied theoretically and experimentally. Methods for noise reduction in the proposed scheme are presented and experimentally demonstrated, while the overall performance is validated for broadband optical detection of ultrasonic fields. The achieved sensitivity is equivalent to the theoretical limit of a 6 MHz narrow-line width laser, which is 40 times higher than what can be usually achieved by incoherent interferometry for the same optical resonator.

Optical Degradation of Colloidal Eu-Complex Embedded in Silica Glass Film Using Reprecipitation and Sol-Gel Methods.

PubMed

Fukuda, Takeshi; Kurabayashi, Tomokazu; Yamaki, Tatsuki

2016-04-01

A reprecipitation method has been investigated for fabricating colloidal nanoparticles using Eu-complex. Herein, we investigated optical degradation characteristics of (1,10-phenanthroline)tris [4,4,4-trifluoro-1-(2-thienyl)-1,3-butanedionato]europium(III) colloidal nanoparticles, which were embedded into a silica glass film fabricated by a conventional sol-gel process. At first, we tried several types of good solvents for the reprecipitation method, and dimethyl sulfoxide (DMSO) is found to be a suitable solvent for realizing the small diameter and the high long-term stability against the ultraviolet irradiation even though the boing point of DMSO is higher than that of water used as a poor solvent. By optimizing the good solvent and the concentration of Eu-complex, the relative photoluminescence intensity of 0.96 was achieved even though the ultraviolet light was continuously irradiated for 90 min. In addition, the average diameter of 106 nm was achieved when DMSO was used as a good solvent, resulting in the high transmittance at a visible wavelength region. Therefore, we can achieve the transparent emissive thin film with a center wavelength of 612 nm, and the optical degradation was drastically reduced by forming nanoparticles.

Numerical investigation of the pseudopotential lattice Boltzmann modeling of liquid-vapor for multi-phase flows

NASA Astrophysics Data System (ADS)

Nemati, Maedeh; Shateri Najaf Abady, Ali Reza; Toghraie, Davood; Karimipour, Arash

2018-01-01

The incorporation of different equations of state into single-component multiphase lattice Boltzmann model is considered in this paper. The original pseudopotential model is first detailed, and several cubic equations of state, the Redlich-Kwong, Redlich-Kwong-Soave, and Peng-Robinson are then incorporated into the lattice Boltzmann model. A comparison of the numerical simulation achievements on the basis of density ratios and spurious currents is used for presentation of the details of phase separation in these non-ideal single-component systems. The paper demonstrates that the scheme for the inter-particle interaction force term as well as the force term incorporation method matters to achieve more accurate and stable results. The velocity shifting method is demonstrated as the force term incorporation method, among many, with accuracy and stability results. Kupershtokh scheme also makes it possible to achieve large density ratio (up to 104) and to reproduce the coexistence curve with high accuracy. Significant reduction of the spurious currents at vapor-liquid interface is another observation. High-density ratio and spurious current reduction resulted from the Redlich-Kwong-Soave and Peng-Robinson EOSs, in higher accordance with the Maxwell construction results.

Accelerating non-contrast-enhanced MR angiography with inflow inversion recovery imaging by skipped phase encoding and edge deghosting (SPEED).

PubMed

Chang, Zheng; Xiang, Qing-San; Shen, Hao; Yin, Fang-Fang

2010-03-01

To accelerate non-contrast-enhanced MR angiography (MRA) with inflow inversion recovery (IFIR) with a fast imaging method, Skipped Phase Encoding and Edge Deghosting (SPEED). IFIR imaging uses a preparatory inversion pulse to reduce signals from static tissue, while leaving inflow arterial blood unaffected, resulting in sparse arterial vasculature on modest tissue background. By taking advantage of vascular sparsity, SPEED can be simplified with a single-layer model to achieve higher efficiency in both scan time reduction and image reconstruction. SPEED can also make use of information available in multiple coils for further acceleration. The techniques are demonstrated with a three-dimensional renal non-contrast-enhanced IFIR MRA study. Images are reconstructed by SPEED based on a single-layer model to achieve an undersampling factor of up to 2.5 using one skipped phase encoding direction. By making use of information available in multiple coils, SPEED can achieve an undersampling factor of up to 8.3 with four receiver coils. The reconstructed images generally have comparable quality as that of the reference images reconstructed from full k-space data. As demonstrated with a three-dimensional renal IFIR scan, SPEED based on a single-layer model is able to reduce scan time further and achieve higher computational efficiency than the original SPEED.

Exploring the Academic Benefits of Friendship Ties for Latino Boys and Girls*

PubMed

Riegle-Crumb, Catherine; Callahan, Rebecca M

2009-09-01

OBJECTIVES: We examine how the racial/ethnic and generational status composition of Latino students' friendship groups is related to their academic achievement and whether there are differential effects by gender. METHODS: We use multivariate regression analyses to examine the effects of friends' characteristics on Latino students' end of high school grades, utilizing data from the Adolescent Health and Academic Achievement Study (AHAA), and its parent survey, the National Longitudinal Study of Adolescent Health (Add Health). RESULTS: For Latina girls, there are positive effects of having more friendship ties to third-plus-generation Latino peers in contrast to dominant culture peers; yet Latino boys benefit academically from ties to all co-ethnic peers. Having friends with higher parental education promotes achievement of both genders. CONCLUSION: Our results counter notions of a pervasive negative peer influence of minority youth and suggest that co-ethnic ties are an important source of social capital for Latino students' achievement.

Global sensitivity analysis for urban water quality modelling: Terminology, convergence and comparison of different methods

NASA Astrophysics Data System (ADS)

Vanrolleghem, Peter A.; Mannina, Giorgio; Cosenza, Alida; Neumann, Marc B.

2015-03-01

Sensitivity analysis represents an important step in improving the understanding and use of environmental models. Indeed, by means of global sensitivity analysis (GSA), modellers may identify both important (factor prioritisation) and non-influential (factor fixing) model factors. No general rule has yet been defined for verifying the convergence of the GSA methods. In order to fill this gap this paper presents a convergence analysis of three widely used GSA methods (SRC, Extended FAST and Morris screening) for an urban drainage stormwater quality-quantity model. After the convergence was achieved the results of each method were compared. In particular, a discussion on peculiarities, applicability, and reliability of the three methods is presented. Moreover, a graphical Venn diagram based classification scheme and a precise terminology for better identifying important, interacting and non-influential factors for each method is proposed. In terms of convergence, it was shown that sensitivity indices related to factors of the quantity model achieve convergence faster. Results for the Morris screening method deviated considerably from the other methods. Factors related to the quality model require a much higher number of simulations than the number suggested in literature for achieving convergence with this method. In fact, the results have shown that the term "screening" is improperly used as the method may exclude important factors from further analysis. Moreover, for the presented application the convergence analysis shows more stable sensitivity coefficients for the Extended-FAST method compared to SRC and Morris screening. Substantial agreement in terms of factor fixing was found between the Morris screening and Extended FAST methods. In general, the water quality related factors exhibited more important interactions than factors related to water quantity. Furthermore, in contrast to water quantity model outputs, water quality model outputs were found to be characterised by high non-linearity.

Reinforcement learning for resource allocation in LEO satellite networks.

PubMed

Usaha, Wipawee; Barria, Javier A

2007-06-01

In this paper, we develop and assess online decision-making algorithms for call admission and routing for low Earth orbit (LEO) satellite networks. It has been shown in a recent paper that, in a LEO satellite system, a semi-Markov decision process formulation of the call admission and routing problem can achieve better performance in terms of an average revenue function than existing routing methods. However, the conventional dynamic programming (DP) numerical solution becomes prohibited as the problem size increases. In this paper, two solution methods based on reinforcement learning (RL) are proposed in order to circumvent the computational burden of DP. The first method is based on an actor-critic method with temporal-difference (TD) learning. The second method is based on a critic-only method, called optimistic TD learning. The algorithms enhance performance in terms of requirements in storage, computational complexity and computational time, and in terms of an overall long-term average revenue function that penalizes blocked calls. Numerical studies are carried out, and the results obtained show that the RL framework can achieve up to 56% higher average revenue over existing routing methods used in LEO satellite networks with reasonable storage and computational requirements.

Ground-based cloud classification by learning stable local binary patterns

NASA Astrophysics Data System (ADS)

Wang, Yu; Shi, Cunzhao; Wang, Chunheng; Xiao, Baihua

2018-07-01

Feature selection and extraction is the first step in implementing pattern classification. The same is true for ground-based cloud classification. Histogram features based on local binary patterns (LBPs) are widely used to classify texture images. However, the conventional uniform LBP approach cannot capture all the dominant patterns in cloud texture images, thereby resulting in low classification performance. In this study, a robust feature extraction method by learning stable LBPs is proposed based on the averaged ranks of the occurrence frequencies of all rotation invariant patterns defined in the LBPs of cloud images. The proposed method is validated with a ground-based cloud classification database comprising five cloud types. Experimental results demonstrate that the proposed method achieves significantly higher classification accuracy than the uniform LBP, local texture patterns (LTP), dominant LBP (DLBP), completed LBP (CLTP) and salient LBP (SaLBP) methods in this cloud image database and under different noise conditions. And the performance of the proposed method is comparable with that of the popular deep convolutional neural network (DCNN) method, but with less computation complexity. Furthermore, the proposed method also achieves superior performance on an independent test data set.

Enhancing chemistry problem-solving achievement using problem categorization

NASA Astrophysics Data System (ADS)

Bunce, Diane M.; Gabel, Dorothy L.; Samuel, John V.

The enhancement of chemistry students' skill in problem solving through problem categorization is the focus of this study. Twenty-four students in a freshman chemistry course for health professionals are taught how to solve problems using the explicit method of problem solving (EMPS) (Bunce & Heikkinen, 1986). The EMPS is an organized approach to problem analysis which includes encoding the information given in a problem (Given, Asked For), relating this to what is already in long-term memory (Recall), and planning a solution (Overall Plan) before a mathematical solution is attempted. In addition to the EMPS training, treatment students receive three 40-minute sessions following achievement tests in which they are taught how to categorize problems. Control students use this time to review the EMPS solutions of test questions. Although problem categorization is involved in one section of the EMPS (Recall), treatment students who received specific training in problem categorization demonstrate significantly higher achievement on combination problems (those problems requiring the use of more than one chemical topic for their solution) at (p = 0.01) than their counterparts. Significantly higher achievement for treatment students is also measured on an unannounced test (p = 0.02). Analysis of interview transcripts of both treatment and control students illustrates a Rolodex approach to problem solving employed by all students in this study. The Rolodex approach involves organizing equations used to solve problems on mental index cards and flipping through them, matching units given when a new problem is to be solved. A second phenomenon observed during student interviews is the absence of a link in the conceptual understanding of the chemical concepts involved in a problem and the problem-solving skills employed to correctly solve problems. This study shows that explicit training in categorization skills and the EMPS can lead to higher achievement in complex problem-solving situations (combination problems and unannounced test). However, such achievement may be limited by the lack of linkages between students' conceptual understanding and improved problem-solving skill.

Open problem-based instruction impacts understanding of physiological concepts differently in undergraduate students

PubMed Central

Franklin, Brandon M.; Xiang, Lin; Collett, Jason A.; Rhoads, Megan K.

2015-01-01

Student populations are diverse such that different types of learners struggle with traditional didactic instruction. Problem-based learning has existed for several decades, but there is still controversy regarding the optimal mode of instruction to ensure success at all levels of students' past achievement. The present study addressed this problem by dividing students into the following three instructional groups for an upper-level course in animal physiology: traditional lecture-style instruction (LI), guided problem-based instruction (GPBI), and open problem-based instruction (OPBI). Student performance was measured by three summative assessments consisting of 50% multiple-choice questions and 50% short-answer questions as well as a final overall course assessment. The present study also examined how students of different academic achievement histories performed under each instructional method. When student achievement levels were not considered, the effects of instructional methods on student outcomes were modest; OPBI students performed moderately better on short-answer exam questions than both LI and GPBI groups. High-achieving students showed no difference in performance for any of the instructional methods on any metric examined. In students with low-achieving academic histories, OPBI students largely outperformed LI students on all metrics (short-answer exam: P < 0.05, d = 1.865; multiple-choice question exam: P < 0.05, d = 1.166; and final score: P < 0.05, d = 1.265). They also outperformed GPBI students on short-answer exam questions (P < 0.05, d = 1.109) but not multiple-choice exam questions (P = 0.071, d = 0.716) or final course outcome (P = 0.328, d = 0.513). These findings strongly suggest that typically low-achieving students perform at a higher level under OPBI as long as the proper support systems (formative assessment and scaffolding) are provided to encourage student success. PMID:26628656

Numerical method for high accuracy index of refraction estimation for spectro-angular surface plasmon resonance systems.

PubMed

Alleyne, Colin J; Kirk, Andrew G; Chien, Wei-Yin; Charette, Paul G

2008-11-24

An eigenvector analysis based algorithm is presented for estimating refractive index changes from 2-D reflectance/dispersion images obtained with spectro-angular surface plasmon resonance systems. High resolution over a large dynamic range can be achieved simultaneously. The method performs well in simulations with noisy data maintaining an error of less than 10(-8) refractive index units with up to six bits of noise on 16 bit quantized image data. Experimental measurements show that the method results in a much higher signal to noise ratio than the standard 1-D weighted centroid dip finding algorithm.

Hybrid ARQ Scheme with Autonomous Retransmission for Multicasting in Wireless Sensor Networks.

PubMed

Jung, Young-Ho; Choi, Jihoon

2017-02-25

A new hybrid automatic repeat request (HARQ) scheme for multicast service for wireless sensor networks is proposed in this study. In the proposed algorithm, the HARQ operation is combined with an autonomous retransmission method that ensure a data packet is transmitted irrespective of whether or not the packet is successfully decoded at the receivers. The optimal number of autonomous retransmissions is determined to ensure maximum spectral efficiency, and a practical method that adjusts the number of autonomous retransmissions for realistic conditions is developed. Simulation results show that the proposed method achieves higher spectral efficiency than existing HARQ techniques.

Investigation on a coupled CFD/DSMC method for continuum-rarefied flows

NASA Astrophysics Data System (ADS)

Tang, Zhenyu; He, Bijiao; Cai, Guobiao

2012-11-01

The purpose of the present work is to investigate the coupled CFD/DSMC method using the existing CFD and DSMC codes developed by the authors. The interface between the continuum and particle regions is determined by the gradient-length local Knudsen number. A coupling scheme combining both state-based and flux-based coupling methods is proposed in the current study. Overlapping grids are established between the different grid systems of CFD and DSMC codes. A hypersonic flow over a 2D cylinder has been simulated using the present coupled method. Comparison has been made between the results obtained from both methods, which shows that the coupled CFD/DSMC method can achieve the same precision as the pure DSMC method and obtain higher computational efficiency.

Theoretical and experimental investigations on the optimal match between compressor and cold finger of the Stirling-type pulse tube cryocooler

NASA Astrophysics Data System (ADS)

Dang, Haizheng; Tan, Jun; Zhang, Lei

2016-06-01

The match between the pulse tube cold finger (PTCF) and the linear compressor of the Stirling-type pulse tube cryocooler plays a vital role in optimizing the compressor efficiency and in improving the PTCF cooling performance as well. In this paper, the interaction of them has been analyzed in a detailed way to reveal the match mechanism, and systematic investigations on the two-way matching have been conducted. The design method of the PTCF to achieve the optimal matching for the given compressor and the counterpart design method of the compressor to achieve the optimal matching for the given PTCF are put forward. Specific experiments are then carried out to verify the conducted theoretical analyses and modeling. For a given linear compressor, a new in-line PTCF which seeks to achieve the optimal match is simulated, designed and tested. And for a given coaxial PTCF, a new dual-opposed moving-coil linear compressor is also developed to match with it. The simulated and experimental results are compared, and fairly good agreements are found between them in both cases. The matched in-line cooler with the newly-designed PTCF has capacities of 4-11.84 W at 80 K with higher than 17% of Carnot efficiency and the mean motor efficiency of 81.5%, and the matched coaxial cooler with the new-designed compressor can provide 2-5.5 W at 60 K with higher than 9.6% of Carnot efficiency and the mean motor efficiency of 83%, which verify the validity of the theoretical investigations on the optimal match and the proposed design methods.

Real-time object recognition in multidimensional images based on joined extended structural tensor and higher-order tensor decomposition methods

NASA Astrophysics Data System (ADS)

Cyganek, Boguslaw; Smolka, Bogdan

2015-02-01

In this paper a system for real-time recognition of objects in multidimensional video signals is proposed. Object recognition is done by pattern projection into the tensor subspaces obtained from the factorization of the signal tensors representing the input signal. However, instead of taking only the intensity signal the novelty of this paper is first to build the Extended Structural Tensor representation from the intensity signal that conveys information on signal intensities, as well as on higher-order statistics of the input signals. This way the higher-order input pattern tensors are built from the training samples. Then, the tensor subspaces are built based on the Higher-Order Singular Value Decomposition of the prototype pattern tensors. Finally, recognition relies on measurements of the distance of a test pattern projected into the tensor subspaces obtained from the training tensors. Due to high-dimensionality of the input data, tensor based methods require high memory and computational resources. However, recent achievements in the technology of the multi-core microprocessors and graphic cards allows real-time operation of the multidimensional methods as is shown and analyzed in this paper based on real examples of object detection in digital images.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hong, Tao; Niu, Zhenbin; Hu, Xunxiang

The development of high performance materials for CO 2 separation and capture will significantly contribute to a solution for climate change. In this work, (bicycloheptenyl) ethyl terminated polydimethylsiloxane (PDMSPNB) membranes with varied cross-link densities were synthesized via ring-opening metathesis polymerization. The developed polymer membranes show higher permeability and better selectivity than those of conventional cross-linked PDMS membrane. The achieved performance (CO 2 permeability ~ 6800 Barrer and CO 2/N 2 selectivity ~ 14) is very promising for practical applications. The key to achieving this high performance is the use of an in-situ cross-linking method of the difunctional PDMS macromonomers, whichmore » provides lightly cross-linked membranes. By combining positron annihilation lifetime spectroscopy, broadband dielectric spectroscopy and gas solubility measurements, we have elucidated the key parameters necessary for achieving their excellent performance.« less

Making the Invisible Visible: Advancing Quantitative Methods in Higher Education Using Critical Race Theory and Intersectionality

ERIC Educational Resources Information Center

López, Nancy; Erwin, Christopher; Binder, Melissa; Chavez, Mario Javier

2018-01-01

We appeal to critical race theory and intersectionality to examine achievement gaps at a large public university in the American southwest from 2000 to 2015. Using white, high-income women as our reference group, we report linear combinations of marginal effects for six-year graduation rates and developmental course taking across 20 distinct…

Higher Weight, Lower Education: A Longitudinal Association between Adolescents' Body Mass Index and Their Subsequent Educational Achievement Level?

ERIC Educational Resources Information Center

Larsen, Junilla K.; Kleinjan, Marloes; Engels, Rutger C. M. E.; Fisher, Jennifer O.; Hermans, Roel

2014-01-01

Background: The purpose of this study was to examine the association between adolescents' body mass index (BMI) z-scores and their subsequent level of schooling, extending previous longitudinal research by using objectively measured weight and height data. Methods: A longitudinal study with 3 study waves (1-year intervals) involving 1248 Dutch…

Does Organizational Learning Affect the Performance of Higher Education Lecturers in Indonesia? The Mediating Role of Teaching Competence

ERIC Educational Resources Information Center

Hartono, Edy; Wahyudi, Sugeng; Harahap, Pahlawansjah; Yuniawan, Ahyar

2017-01-01

This study aims to analyze the relationship between lecturers' performance and their teaching competence, measured by antecedent variables of organizational learning and need for achievement. It used the Structure Equation Model as data analysis technique, and the random sampling method to collect data from 207 lecturers of private universities in…

Credit Where Credit Is Due: An Approach to Education Returns Based on Shapley Values

ERIC Educational Resources Information Center

Barakat, Bilal; Crespo Cuaresma, Jesus

2017-01-01

We propose the use of methods based on the Shapley value to assess the fact that private returns to lower levels of educational attainment should be credited with part of the returns from higher attainment levels, since achieving primary education is a necessary condition to enter secondary and tertiary educational levels. We apply the proposed…

Instructional Coaching in Higher Education: Partnering to Infuse ELL Instructional Practices into Social Studies Courses

ERIC Educational Resources Information Center

Thibault, Malissa

2017-01-01

As evidenced in the growing achievement gap between English language learners (ELLs) and their non-ELL counterparts, it is clear future teachers need to be better prepared to work with ELLs. This study examined the influence of infusing ELL strategies into methods courses through instructional coaching. This study was inspired by the larger…

Layered method of electrode for solid oxide electrochemical cells

DOEpatents

Jensen, Russell R.

1991-07-30

A process for fabricating a fuel electrode comprising: slurry dipping to form layers which are structurally graded from all or mostly all stabilized zirconia at a first layer, to an outer most layer of substantially all metal powder, such an nickel. Higher performaance fuel electrodes may be achieved if sinter active stabilized zirconia doped for electronic conductivity is used.

Biosynthesized silver nanoparticles: are they effective antimicrobials?

PubMed Central

Peiris, Mudara K; Gunasekara, Chinthika P; Jayaweera, Pradeep M; Arachchi, Nuwan DH; Fernando, Neluka

2017-01-01

BACKGROUND Silver nanoparticles (AgNPs) are increasingly being used in medical applications. Therefore, cost effective and green methods for generating AgNPs are required. OBJECTIVES This study aimed towards the biosynthesis, characterisation, and determination of antimicrobial activity of AgNPs produced using Pseudomonas aeruginosa ATCC 27853. METHODS Culture conditions (AgNO3 concentration, pH, and incubation temperature and time) were optimized to achieve maximum AgNP production. The characterisation of AgNPs and their stability were evaluated by UV-visible spectrophotometry and scanning electron microscopy. FINDINGS The characteristic UV-visible absorbance peak was observed in the 420–430 nm range. Most of the particles were spherical in shape within a size range of 33–300 nm. The biosynthesized AgNPs exhibited higher stability than that exhibited by chemically synthesized AgNPs in the presence of electrolytes. The biosynthesized AgNPs exhibited antimicrobial activity against Escherichia coli, P. aeruginosa, Salmonella typhimurium, Staphylococcus aureus, methicillin-resistant S. aureus, Acinetobacter baumannii, and Candida albicans. MAIN CONCLUSION As compared to the tested Gram-negative bacteria, Gram-positive bacteria required higher contact time to achieve 100% reduction of colony forming units when treated with biosynthesized AgNPs produced using P. aeruginosa. PMID:28767978

Comparison of Machine Learning Methods for the Arterial Hypertension Diagnostics

PubMed Central

Belo, David; Gamboa, Hugo

2017-01-01

The paper presents results of machine learning approach accuracy applied analysis of cardiac activity. The study evaluates the diagnostics possibilities of the arterial hypertension by means of the short-term heart rate variability signals. Two groups were studied: 30 relatively healthy volunteers and 40 patients suffering from the arterial hypertension of II-III degree. The following machine learning approaches were studied: linear and quadratic discriminant analysis, k-nearest neighbors, support vector machine with radial basis, decision trees, and naive Bayes classifier. Moreover, in the study, different methods of feature extraction are analyzed: statistical, spectral, wavelet, and multifractal. All in all, 53 features were investigated. Investigation results show that discriminant analysis achieves the highest classification accuracy. The suggested approach of noncorrelated feature set search achieved higher results than data set based on the principal components. PMID:28831239

Improving the lateral resolution of quartz tuning fork-based sensors in liquid by integrating commercial AFM tips into the fiber end.

PubMed

Gonzalez, Laura; Martínez-Martín, David; Otero, Jorge; de Pablo, Pedro José; Puig-Vidal, Manel; Gómez-Herrero, Julio

2015-01-14

The use of quartz tuning fork sensors as probes for scanning probe microscopy is growing in popularity. Working in shear mode, some methods achieve a lateral resolution comparable with that obtained with standard cantilevered probes, but only in experiments conducted in air or vacuum. Here, we report a method to produce and use commercial AFM tips in electrically driven quartz tuning fork sensors operating in shear mode in a liquid environment. The process is based on attaching a standard AFM tip to the end of a fiber probe which has previously been sharpened. Only the end of the probe is immersed in the buffer solution during imaging. The lateral resolution achieved is about 6 times higher than that of the etched microfiber on its own.

Have First-Year Emergency Medicine Residents Achieved Level 1 on Care-Based Milestones?

PubMed Central

Weizberg, Moshe; Bond, Michael C.; Cassara, Michael; Doty, Christopher; Seamon, Jason

2015-01-01

Background Residents in Accreditation Council for Graduate Medical Education accredited emergency medicine (EM) residencies were assessed on 23 educational milestones to capture their progression from medical student level (Level 1) to that of an EM attending physician (Level 5). Level 1 was conceptualized to be at the level of an incoming postgraduate year (PGY)-1 resident; however, this has not been confirmed. Objectives Our primary objective in this study was to assess incoming PGY-1 residents to determine what percentage achieved Level 1 for the 8 emergency department (ED) patient care–based milestones (PC 1–8), as assessed by faculty. Secondary objectives involved assessing what percentage of residents had achieved Level 1 as assessed by themselves, and finally, we calculated the absolute differences between self- and faculty assessments. Methods Incoming PGY-1 residents at 4 EM residencies were assessed by faculty and themselves during their first month of residency. Performance anchors were adapted from ACGME milestones. Results Forty-one residents from 4 programs were included. The percentage of residents who achieved Level 1 for each subcompetency on faculty assessment ranged from 20% to 73%, and on self-assessment from 34% to 92%. The majority did not achieve Level 1 on faculty assessment of milestones PC-2, PC-3, PC-5a, and PC-6, and on self-assessment of PC-3 and PC-5a. Self-assessment was higher than faculty assessment for PC-2, PC-5b, and PC-6. Conclusions Less than 75% of PGY-1 residents achieved Level 1 for ED care-based milestones. The majority did not achieve Level 1 on 4 milestones. Self-assessments were higher than faculty assessments for several milestones. PMID:26692971

Examining the integrity of measurement of cognitive abilities in the prediction of achievement: Comparisons and contrasts across variables from higher-order and bifactor models.

PubMed

Benson, Nicholas F; Kranzler, John H; Floyd, Randy G

2016-10-01

Prior research examining cognitive ability and academic achievement relations have been based on different theoretical models, have employed both latent variables as well as observed variables, and have used a variety of analytic methods. Not surprisingly, results have been inconsistent across studies. The aims of this study were to (a) examine how relations between psychometric g, Cattell-Horn-Carroll (CHC) broad abilities, and academic achievement differ across higher-order and bifactor models; (b) examine how well various types of observed scores corresponded with latent variables; and (c) compare two types of observed scores (i.e., refined and non-refined factor scores) as predictors of academic achievement. Results suggest that cognitive-achievement relations vary across theoretical models and that both types of factor scores tend to correspond well with the models on which they are based. However, orthogonal refined factor scores (derived from a bifactor model) have the advantage of controlling for multicollinearity arising from the measurement of psychometric g across all measures of cognitive abilities. Results indicate that the refined factor scores provide more precise representations of their targeted constructs than non-refined factor scores and maintain close correspondence with the cognitive-achievement relations observed for latent variables. Thus, we argue that orthogonal refined factor scores provide more accurate representations of the relations between CHC broad abilities and achievement outcomes than non-refined scores do. Further, the use of refined factor scores addresses calls for the application of scores based on latent variable models. Copyright © 2016 Society for the Study of School Psychology. Published by Elsevier Ltd. All rights reserved.

Relationships among constructivist learning environment perceptions, motivational beliefs, self-regulation and science achievement

NASA Astrophysics Data System (ADS)

Kingir, Sevgi; Tas, Yasemin; Gok, Gulsum; Sungur Vural, Semra

2013-11-01

Background. There are attempts to integrate learning environment research with motivation and self-regulation research that considers social context influences an individual's motivation, self-regulation and, in turn, academic performance. Purpose. This study explored the relationships among constructivist learning environment perception variables (personal relevance, uncertainty, shared control, critical voice, student negotiation), motivational beliefs (self-efficacy, intrinsic interest, goal orientation), self-regulation, and science achievement. Sample. The sample for this study comprised 802 Grade 8 students from 14 public middle schools in a district of Ankara in Turkey. Design and methods. Students were administered 4 instruments: Constructivist Learning Environment Survey, Goal Achievement Questionnaire, Motivated Strategies for Learning Questionnaire, and Science Achievement Test. LISREL 8.7 program with SIMPLIS programming language was used to test the conceptual model. Providing appropriate fit indices for the proposed model, the standardized path coefficients for direct effects were examined. Results. At least one dimension of the constructivist learning environment was associated with students' intrinsic interest, goal orientation, self-efficacy, self-regulation, and science achievement. Self-efficacy emerged as the strongest predictor of both mastery and performance avoidance goals rather than the approach goals. Intrinsic value was found to be significantly linked to science achievement through its effect on self-regulation. The relationships between self-efficacy and self-regulation and between goal orientation and science achievement were not significant. Conclusion. In a classroom environment supporting student autonomy and control, students tend to develop higher interest in tasks, use more self-regulatory strategies, and demonstrate higher academic performance. Science teachers are highly recommended to consider these findings when designing their lessons. For the creation of such a learning environment, teachers can design open-ended inquiry activities in which students have opportunities to take responsibility, reflect on their views, and accomplish challenging tasks.

Effectiveness of various innovative learning methods in health science classrooms: a meta-analysis.

PubMed

Kalaian, Sema A; Kasim, Rafa M

2017-12-01

This study reports the results of a meta-analysis of the available literature on the effectiveness of various forms of innovative small-group learning methods on student achievement in undergraduate college health science classrooms. The results of the analysis revealed that most of the primary studies supported the effectiveness of the small-group learning methods in improving students' academic achievement with an overall weighted average effect-size of 0.59 in standard deviation units favoring small-group learning methods. The subgroup analysis showed that the various forms of innovative and reform-based small-group learning interventions appeared to be significantly more effective for students in higher levels of college classes (sophomore, junior, and senior levels), students in other countries (non-U.S.) worldwide, students in groups of four or less, and students who choose their own group. The random-effects meta-regression results revealed that the effect sizes were influenced significantly by the instructional duration of the primary studies. This means that studies with longer hours of instruction yielded higher effect sizes and on average every 1 h increase in instruction, the predicted increase in effect size was 0.009 standard deviation units, which is considered as a small effect. These results may help health science and nursing educators by providing guidance in identifying the conditions under which various forms of innovative small-group learning pedagogies are collectively more effective than the traditional lecture-based teaching instruction.

Physical activity and health-related quality of life among older men: an examination of current physical activity recommendations.

PubMed

Vallance, Jeff K; Eurich, Dean T; Lavallee, Celeste M; Johnson, Steven T

2012-01-01

To determine differences in health-related quality of life (HRQoL) between older men achieving versus not achieving American College of Sports Medicine (ACSM) and the United States Department of Health and Human Services recommendations (USDHHS) physical activity (PA) recommendations. Older-aged men (≥ 55 years) completed a mailed survey that assessed self-reported PA and HRQoL. Data were collected between September and October of 2010. 387 older men (Mean age=65) completed the survey. Under half (48%) reported achieving the ACSM recommendation while 64% reported achieving the USDHHS recommendation. Older men achieving the ACSM recommendation reported significantly higher scores in physical health (Δ=3.5, p<0.001), mental health (Δ=4.4, p<0.001), and global health (Δ=4.3, p<0.001) component scores compared to those not achieving the recommendation. Those achieving the higher dose recommended by the USDHHS (≥ 300 min per week of moderate-intensity activity) reported significantly higher scores on the PHC (Δ=2.1, p=0.029) and GHC (Δ=2.3, p=0.027) scales compared to those achieving the USDHHS base recommendation (150-299.9 min per week of moderate-intensity activity). Self-reported PA was significantly and positively associated with higher HRQoL scores among older men. Associations were stronger for those achieving a higher volume of PA. Copyright © 2012 Elsevier Inc. All rights reserved.

PSA Nadir of <0.5 ng/mL Following Brachytherapy for Early-Stage Prostate Adenocarcinoma is Associated With Freedom From Prostate-Specific Antigen Failure

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ko, Eric C.; Stone, Nelson N.; Department of Urology, Mount Sinai Medical Center, New York, NY

2012-06-01

Purpose: Because limited information exists regarding whether the rate or magnitude of PSA decline following brachytherapy predicts long-term clinical outcomes, we evaluated whether achieving a prostate-specific antigen (PSA) nadir (nPSA) <0.5 ng/mL following brachytherapy is associated with decreased PSA failure and/or distant metastasis. Methods and Materials: We retrospectively analyzed our database of early-stage prostate adenocarcinoma patients who underwent brachytherapy, excluding those receiving androgen-deprivation therapy and those with <2 years follow-up. Median and mean pretreatment PSA were 6 ng/mL and 7.16 ng/mL, respectively. By clinical stage, 775 were low risk ({<=}T2a), 126 were intermediate risk (T2b), and 20 were high riskmore » (>T2b). By Gleason score, 840 were low risk ({<=}6), 71 were intermediate risk (7), and 10 were high risk (>7). Patients were treated with brachytherapy only (I-125, n = 779, or Pd-103, n = 47), or brachytherapy + external-beam radiation therapy (n = 95). Median follow-up was 6.3 years. We noted whether nPSA <0.5 ng/mL was achieved and the time to achieve this nadir and tested for associations with pretreatment risk factors. We also determined whether this PSA endpoint was associated with decreased PSA failure or distant metastasis. Results: Absence of high-risk factors in clinical stage ({<=}T2b), Gleason score ({<=}7), and pretreatment PSA ({<=}20 ng/mL) was significantly associated with achieving nPSA <0.5 ng/mL. By Kaplan-Meier analysis, patients achieving nPSA <0.5 ng/mL had significantly higher long-term freedom from biochemical failure (FFBF) than nonresponders (5-year FFBF: 95.2 {+-} 0.8% vs. 71.5 {+-} 6.7%; p < 0.0005). Among responders, those who achieved nPSA <0.5 ng/mL in {<=}5 years had higher FFBF than those requiring >5 years (5-year FFBF: 96.7 {+-} 0.7% vs. 80.8 {+-} 4.6%; p < 0.0005). On multivariate analysis, patients who achieved nPSA <0.5 ng/mL in {<=}5 years had significantly higher FFBF than other patients. Conclusions: Pretreatment risk factors (clinical tumor stage, Gleason score, pretreatment PSA) strongly predict for patients achieving nPSA <0.5 ng/mL following brachytherapy, and this cohort had significantly higher long-term FFBF.« less

Effects of collaboration and inquiry on reasoning and achievement in biology

NASA Astrophysics Data System (ADS)

Jensen, Jamie Lee

The primary purpose of the present study was to compare the effectiveness of two collaborative grouping strategies and two instructional methods in terms of gains in reasoning ability and achievement in college biology. In order to do so, a quasi-experimental study was performed in which students were placed in one of four treatment conditions: heterogeneous grouping within inquiry instruction, homogeneous grouping within inquiry instruction, heterogeneous grouping within non-inquiry instruction, and homogeneous grouping within non-inquiry instruction. Students were placed in groups based on initial reasoning level. Reasoning levels and achievement gains were assessed at the end of the study. Results showed that within non-inquiry instruction, heterogeneous mean group scores were higher in both reasoning and achievement than homogeneous groups. In contrast, within inquiry instruction, homogeneous mean group scores were higher in both reasoning and achievement. Inquiry instruction, as a whole, significantly outperformed non-inquiry instruction in the development of reasoning ability. Within inquiry instruction, low-ability students had significantly greater reasoning gains when grouped homogeneously. These results support Piaget's developmental theory and contradict Vygotsky's developmental theory. These results also suggest that the success of one grouping strategy over another is highly dependent upon the nature of instruction, which may be a cause for such conflicting views on grouping strategies within the educational literature. In addition, inquiry instruction led to students having greater confidence in their reasoning ability as well as a more positive attitude toward collaboration. Instructional implications are discussed.

The influence of tightening sequence and method on screw preload in implant superstructures.

PubMed

Al-Sahan, Maha M; Al Maflehi, Nassr S; Akeel, Riyadh F

2014-01-01

This study evaluated the effect of six screw-tightening sequences and two tightening methods on the screw preload in implant-supported superstructures. The preload was measured using strain gauges following the screw tightening of a metal framework connected to four implants. The experiment included six sequences ([1] 1-2-3-4, [2] 4-2-3-1, [3] 4-3-1-2, [4] 1-4-2-3, [5] 2-3-4-1, and [6] 3-2-4-1), two methods (onestep, three-step), and five replications. Significant differences were found between tightening sequences and methods. In the three-step method, a higher total preload was found in sequences 2 (312 ± 85 N), 3 (246 ± 54 N), and 4 (310 ± 96 N). In the one-step method, a higher total preload was found in sequences 1 (286 ± 94 N), 5 (764 ± 142 N), and 6 (350 ± 69 N). It is concluded that the highest total screw preload was achieved when anterior implants of the superstructure were first tightened in one step, followed by posterior implants.

Morphological self-organizing feature map neural network with applications to automatic target recognition

NASA Astrophysics Data System (ADS)

Zhang, Shijun; Jing, Zhongliang; Li, Jianxun

2005-01-01

The rotation invariant feature of the target is obtained using the multi-direction feature extraction property of the steerable filter. Combining the morphological operation top-hat transform with the self-organizing feature map neural network, the adaptive topological region is selected. Using the erosion operation, the topological region shrinkage is achieved. The steerable filter based morphological self-organizing feature map neural network is applied to automatic target recognition of binary standard patterns and real-world infrared sequence images. Compared with Hamming network and morphological shared-weight networks respectively, the higher recognition correct rate, robust adaptability, quick training, and better generalization of the proposed method are achieved.

An Innovative Teaching Method To Promote Active Learning: Team-Based Learning

NASA Astrophysics Data System (ADS)

Balasubramanian, R.

2007-12-01

Traditional teaching practice based on the textbook-whiteboard- lecture-homework-test paradigm is not very effective in helping students with diverse academic backgrounds achieve higher-order critical thinking skills such as analysis, synthesis, and evaluation. Consequently, there is a critical need for developing a new pedagogical approach to create a collaborative and interactive learning environment in which students with complementary academic backgrounds and learning skills can work together to enhance their learning outcomes. In this presentation, I will discuss an innovative teaching method ('Team-Based Learning (TBL)") which I recently developed at National University of Singapore to promote active learning among students in the environmental engineering program with learning abilities. I implemented this new educational activity in a graduate course. Student feedback indicates that this pedagogical approach is appealing to most students, and promotes active & interactive learning in class. Data will be presented to show that the innovative teaching method has contributed to improved student learning and achievement.

Achieving a new controllable male contraception by the photothermal effect of gold nanorods.

PubMed

Li, Wen-qing; Sun, Chun-yang; Wang, Feng; Wang, Yu-cai; Zhai, Yi-wen; Liang, Meng; Liu, Wen-jing; Liu, Zhi-min; Wang, Jun; Sun, Fei

2013-06-12

During the process of human civilization, owning household pets has become increasingly popular. However, dogs and cats may be reservoirs or vectors of transmissible diseases to humans. Confronted with the overpopulation of pets, traditional contraception methods, surgical methods of sterilization, for animals are used, namely, ovariohysterectomy and orchidectomy. Therefore, a simple, nonsurgical, controllable, more effective and less expensive contraception method is highly desirable. In this study, we show that in situ testicular injection of methoxy poly(ethylene glycol)-modified gold nanorods with near-infrared irradiation in male mice can achieve short-lived or permanent male infertility. In a lower hyperthermia treatment, the morphology of testes and seminiferous tubules is only partly injured, and fertility indices are decreased to 10% at day 7, then recovered to 50% at day 60. In a higher hyperthermia treatment, the morphology of testes and seminiferous tubules are totally destroyed, and fertility indices are decreased to 0 at day 7. Overall, our results indicate a potential application of plasmonic nanomaterials for male contraception.

A pseudo-discrete algebraic reconstruction technique (PDART) prior image-based suppression of high density artifacts in computed tomography

NASA Astrophysics Data System (ADS)

Pua, Rizza; Park, Miran; Wi, Sunhee; Cho, Seungryong

2016-12-01

We propose a hybrid metal artifact reduction (MAR) approach for computed tomography (CT) that is computationally more efficient than a fully iterative reconstruction method, but at the same time achieves superior image quality to the interpolation-based in-painting techniques. Our proposed MAR method, an image-based artifact subtraction approach, utilizes an intermediate prior image reconstructed via PDART to recover the background information underlying the high density objects. For comparison, prior images generated by total-variation minimization (TVM) algorithm, as a realization of fully iterative approach, were also utilized as intermediate images. From the simulation and real experimental results, it has been shown that PDART drastically accelerates the reconstruction to an acceptable quality of prior images. Incorporating PDART-reconstructed prior images in the proposed MAR scheme achieved higher quality images than those by a conventional in-painting method. Furthermore, the results were comparable to the fully iterative MAR that uses high-quality TVM prior images.

The effects of modeling instruction on high school physics academic achievement

NASA Astrophysics Data System (ADS)

Wright, Tiffanie L.

The purpose of this study was to explore whether Modeling Instruction, compared to traditional lecturing, is an effective instructional method to promote academic achievement in selected high school physics classes at a rural middle Tennessee high school. This study used an ex post facto , quasi-experimental research methodology. The independent variables in this study were the instructional methods of teaching. The treatment variable was Modeling Instruction and the control variable was traditional lecture instruction. The Treatment Group consisted of participants in Physical World Concepts who received Modeling Instruction. The Control Group consisted of participants in Physical Science who received traditional lecture instruction. The dependent variable was gains scores on the Force Concepts Inventory (FCI). The participants for this study were 133 students each in both the Treatment and Control Groups (n = 266), who attended a public, high school in rural middle Tennessee. The participants were administered the Force Concepts Inventory (FCI) prior to being taught the mechanics of physics. The FCI data were entered into the computer-based Statistical Package for the Social Science (SPSS). Two independent samples t-tests were conducted to answer the research questions. There was a statistically significant difference between the treatment and control groups concerning the instructional method. Modeling Instructional methods were found to be effective in increasing the academic achievement of students in high school physics. There was no statistically significant difference between FCI gains scores for gender. Gender was found to have no effect on the academic achievement of students in high school physics classes. However, even though there was not a statistically significant difference, female students' gains scores were higher than male students' gains scores when Modeling Instructional methods of teaching were used. Based on these findings, it is recommended that high school science teachers should use Modeling Instructional methods of teaching daily in their classrooms. A recommendation for further research is to expand the Modeling Instructional methods of teaching into different content areas, (i.e., reading and language arts) to explore academic achievement gains.

The effect of four instructional methods, gender, and time of testing on the achievement of sixth graders learning to interpret graphs

NASA Astrophysics Data System (ADS)

Young, Jerry Wayne

The purpose of this study was to determine the effects of four instructional methods (direct instruction, computer-aided instruction, video observation, and microcomputer-based lab activities), gender, and time of testing (pretest, immediate posttest for determining the immediate effect of instruction, and a delayed posttest two weeks later to determine the retained effect of the instruction) on the achievement of sixth graders who were learning to interpret graphs of displacement and velocity. The dependent variable of achievement was reflected in the scores earned by students on a testing instrument of established validity and reliability. The 107 students participating in the study were divided by gender and were then randomly assigned to the four treatment groups, each taught by a different teacher. Each group had approximately equal numbers of males and females. The students were pretested and then involved in two class periods of the instructional method which was unique to their group. Immediately following treatment they were posttested and two weeks later they were posttested again. The data in the form of test scores were analyzed with a two-way split-plot analysis of variance to determine if there was significant interaction among technique, gender, and time of testing. When significant interaction was indicated, the Tukey HSD test was used to determine specific mean differences. The results of the analysis indicated no gender effect. Only students in the direct instruction group and the microcomputer-based laboratory group had significantly higher posttest-1 scores than pretest scores. They also had significantly higher posttest-2 scores than pretest scores. This suggests that the learning was retained. The other groups experienced no significant differences among pretest, posttest-1, and posttest-2 scores. Recommendations are that direct instruction and microcomputer-based laboratory activities should be considered as effective stand-alone methods for teaching sixth grade students to interpret graphs of displacement and velocity. However, video and computer instruction may serve as supplemental activities.

Development and optimization of a novel sample preparation method cored on functionalized nanofibers mat-solid-phase extraction for the simultaneous efficient extraction of illegal anionic and cationic dyes in foods.

PubMed

Qi, Feifei; Jian, Ningge; Qian, Liangliang; Cao, Weixin; Xu, Qian; Li, Jian

2017-09-01

A simple and efficient three-step sample preparation method was developed and optimized for the simultaneous analysis of illegal anionic and cationic dyes (acid orange 7, metanil yellow, auramine-O, and chrysoidine) in food samples. A novel solid-phase extraction (SPE) procedure based on nanofibers mat (NFsM) was proposed after solvent extraction and freeze-salting out purification. The preferred SPE sorbent was selected from five functionalized NFsMs by orthogonal experimental design, and the optimization of SPE parameters was achieved through response surface methodology (RSM) based on the Box-Behnken design (BBD). Under the optimal conditions, the target analytes could be completely adsorbed by polypyrrole-functionalized polyacrylonitrile NFsM (PPy/PAN NFsM), and the eluent was directly analyzed by high-performance liquid chromatography-diode array detection (HPLC-DAD). The limits of detection (LODs) were between 0.002 and 0.01 mg kg -1 , and satisfactory linearity with correlation coefficients (R > 0.99) for each dye in all samples was achieved. Compared with the Chinese standard method and the published methods, the proposed method was simplified greatly with much lower requirement of sorbent (5.0 mg) and organic solvent (2.8 mL) and higher sample preparation speed (10 min/sample), while higher recovery (83.6-116.5%) and precision (RSDs < 7.1%) were obtained. With this developed method, we have successfully detected illegal ionic dyes in three common representative foods: yellow croaker, soybean products, and chili seasonings. Graphical abstract Schematic representation of the process of the three-step sample preparation.

A supervised learning approach for Crohn's disease detection using higher-order image statistics and a novel shape asymmetry measure.

PubMed

Mahapatra, Dwarikanath; Schueffler, Peter; Tielbeek, Jeroen A W; Buhmann, Joachim M; Vos, Franciscus M

2013-10-01

Increasing incidence of Crohn's disease (CD) in the Western world has made its accurate diagnosis an important medical challenge. The current reference standard for diagnosis, colonoscopy, is time-consuming and invasive while magnetic resonance imaging (MRI) has emerged as the preferred noninvasive procedure over colonoscopy. Current MRI approaches assess rate of contrast enhancement and bowel wall thickness, and rely on extensive manual segmentation for accurate analysis. We propose a supervised learning method for the identification and localization of regions in abdominal magnetic resonance images that have been affected by CD. Low-level features like intensity and texture are used with shape asymmetry information to distinguish between diseased and normal regions. Particular emphasis is laid on a novel entropy-based shape asymmetry method and higher-order statistics like skewness and kurtosis. Multi-scale feature extraction renders the method robust. Experiments on real patient data show that our features achieve a high level of accuracy and perform better than two competing methods.

Face-iris multimodal biometric scheme based on feature level fusion

NASA Astrophysics Data System (ADS)

Huo, Guang; Liu, Yuanning; Zhu, Xiaodong; Dong, Hongxing; He, Fei

2015-11-01

Unlike score level fusion, feature level fusion demands all the features extracted from unimodal traits with high distinguishability, as well as homogeneity and compatibility, which is difficult to achieve. Therefore, most multimodal biometric research focuses on score level fusion, whereas few investigate feature level fusion. We propose a face-iris recognition method based on feature level fusion. We build a special two-dimensional-Gabor filter bank to extract local texture features from face and iris images, and then transform them by histogram statistics into an energy-orientation variance histogram feature with lower dimensions and higher distinguishability. Finally, through a fusion-recognition strategy based on principal components analysis and support vector machine (FRSPS), feature level fusion and one-to-n identification are accomplished. The experimental results demonstrate that this method can not only effectively extract face and iris features but also provide higher recognition accuracy. Compared with some state-of-the-art fusion methods, the proposed method has a significant performance advantage.

Achievement of learning outcome after implemented physical modules based on problem based learning

NASA Astrophysics Data System (ADS)

Isna, R.; Masykuri, M.; Sukarmin

2018-03-01

Implementation of Problem BasedLearning (PBL) modules can grow the students' thinking skills to solve the problems in daily life and equip the students into higher education levels. The purpose of this research is to know the achievement of learning outcome after implementation physics module based on PBL in Newton,s Law of Gravity. This research method use the experimental method with posttest only group design. To know the achievement of student learning outcomes was analyzed using t test through application of SPSS 18. Based on research result, it is found that the average of student learning outcomes after appliying physics module based on PBL has reached the minimal exhaustiveness criteria. In addition, students' scientific attitudes also improved at each meeting. Presentation activities which contained at learning sync are also able to practice speaking skills and broaden their knowledge. Looking at some shortcomings during the study, it is suggested the issues raised into learning should be a problem close to the life of students so that, the students are more active and enthusiastic in following the learning of physics.

High-Efficiency Photovoltaic Devices using Trap-Controlled Quantum-Dot Ink prepared via Phase-Transfer Exchange.

PubMed

Aqoma, Havid; Al Mubarok, Muhibullah; Hadmojo, Wisnu Tantyo; Lee, Eun-Hye; Kim, Tae-Wook; Ahn, Tae Kyu; Oh, Seung-Hwan; Jang, Sung-Yeon

2017-05-01

Colloidal-quantum-dot (CQD) photovoltaic devices are promising candidates for low-cost power sources owing to their low-temperature solution processability and bandgap tunability. A power conversion efficiency (PCE) of >10% is achieved for these devices; however, there are several remaining obstacles to their commercialization, including their high energy loss due to surface trap states and the complexity of the multiple-step CQD-layer-deposition process. Herein, high-efficiency photovoltaic devices prepared with CQD-ink using a phase-transfer-exchange (PTE) method are reported. Using CQD-ink, the fabrication of active layers by single-step coating and the suppression of surface trap states are achieved simultaneously. The CQD-ink photovoltaic devices achieve much higher PCEs (10.15% with a certified PCE of 9.61%) than the control devices (7.85%) owing to improved charge drift and diffusion. Notably, the CQD-ink devices show much lower energy loss than other reported high-efficiency CQD devices. This result reveals that the PTE method is an effective strategy for controlling trap states in CQDs. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Microwave assisted direct saponification for the simultaneous determination of cholesterol and cholesterol oxides in shrimp.

PubMed

Souza, Hugo A L; Mariutti, Lilian R B; Bragagnolo, Neura

2017-05-01

A novel microwave-assisted direct saponification method for the simultaneous determination of cholesterol and cholesterol oxides in shrimp was developed and validated. Optimal saponification conditions, determined by means of an experimental design, were achieved using 500mg of sample and 20mL of 1mol/L KOH ethanol solution for 16min at 45°C at maximum power at 200W and magnetic stirring at 120rpm. Higher extraction of cholesterol oxides in a reduced saponification time (∼75 times) was achieved in comparison with the direct cold saponification method. The new method showed low detection (≤0.57μg/mL) and quantification (≤1.73μg/mL) limits, good repeatability (≤10.50% intraday and ≤8.56% interday) and low artifact formation (evaluated by using a deuterated cholesterol-D6 standard). Raw, salted and dried-salted shrimps were successfully analyzed by the validated method. The content of cholesterol oxides increased after salting and decreased after drying. Copyright © 2016 Elsevier Ltd. All rights reserved.

Feature extraction based on extended multi-attribute profiles and sparse autoencoder for remote sensing image classification

NASA Astrophysics Data System (ADS)

Teffahi, Hanane; Yao, Hongxun; Belabid, Nasreddine; Chaib, Souleyman

2018-02-01

The satellite images with very high spatial resolution have been recently widely used in image classification topic as it has become challenging task in remote sensing field. Due to a number of limitations such as the redundancy of features and the high dimensionality of the data, different classification methods have been proposed for remote sensing images classification particularly the methods using feature extraction techniques. This paper propose a simple efficient method exploiting the capability of extended multi-attribute profiles (EMAP) with sparse autoencoder (SAE) for remote sensing image classification. The proposed method is used to classify various remote sensing datasets including hyperspectral and multispectral images by extracting spatial and spectral features based on the combination of EMAP and SAE by linking them to kernel support vector machine (SVM) for classification. Experiments on new hyperspectral image "Huston data" and multispectral image "Washington DC data" shows that this new scheme can achieve better performance of feature learning than the primitive features, traditional classifiers and ordinary autoencoder and has huge potential to achieve higher accuracy for classification in short running time.

Evaluation of viral removal by nanofiltration using real-time quantitative polymerase chain reaction.

PubMed

Zhao, Xiaowen; Bailey, Mark R; Emery, Warren R; Lambooy, Peter K; Chen, Dayue

2007-06-01

Nanofiltration is commonly introduced into purification processes of biologics produced in mammalian cells to serve as a designated step for removal of potential exogenous viral contaminants and endogenous retrovirus-like particles. The LRV (log reduction value) achieved by nanofiltration is often determined by cell-based infectivity assay, which is time-consuming and labour-intensive. We have explored the possibility of employing QPCR (quantitative PCR) to evaluate LRV achieved by nanofiltration in scaled-down studies using two model viruses, namely xenotropic murine leukemia virus and murine minute virus. We report here the successful development of a QPCR-based method suitable for quantification of virus removal by nanofiltration. The method includes a nuclease treatment step to remove free viral nucleic acids, while viral genome associated with intact virus particles is shielded from the nuclease. In addition, HIV Armored RNA was included as an internal control to ensure the accuracy and reliability of the method. The QPCRbased method described here provides several advantages such as better sensitivity, faster turnaround time, reduced cost and higher throughput over the traditional cell-based infectivity assays.

A fast learning method for large scale and multi-class samples of SVM

NASA Astrophysics Data System (ADS)

Fan, Yu; Guo, Huiming

2017-06-01

A multi-class classification SVM(Support Vector Machine) fast learning method based on binary tree is presented to solve its low learning efficiency when SVM processing large scale multi-class samples. This paper adopts bottom-up method to set up binary tree hierarchy structure, according to achieved hierarchy structure, sub-classifier learns from corresponding samples of each node. During the learning, several class clusters are generated after the first clustering of the training samples. Firstly, central points are extracted from those class clusters which just have one type of samples. For those which have two types of samples, cluster numbers of their positive and negative samples are set respectively according to their mixture degree, secondary clustering undertaken afterwards, after which, central points are extracted from achieved sub-class clusters. By learning from the reduced samples formed by the integration of extracted central points above, sub-classifiers are obtained. Simulation experiment shows that, this fast learning method, which is based on multi-level clustering, can guarantee higher classification accuracy, greatly reduce sample numbers and effectively improve learning efficiency.

Multi-test cervical cancer diagnosis with missing data estimation

NASA Astrophysics Data System (ADS)

Xu, Tao; Huang, Xiaolei; Kim, Edward; Long, L. Rodney; Antani, Sameer

2015-03-01

Cervical cancer is a leading most common type of cancer for women worldwide. Existing screening programs for cervical cancer suffer from low sensitivity. Using images of the cervix (cervigrams) as an aid in detecting pre-cancerous changes to the cervix has good potential to improve sensitivity and help reduce the number of cervical cancer cases. In this paper, we present a method that utilizes multi-modality information extracted from multiple tests of a patient's visit to classify the patient visit to be either low-risk or high-risk. Our algorithm integrates image features and text features to make a diagnosis. We also present two strategies to estimate the missing values in text features: Image Classifier Supervised Mean Imputation (ICSMI) and Image Classifier Supervised Linear Interpolation (ICSLI). We evaluate our method on a large medical dataset and compare it with several alternative approaches. The results show that the proposed method with ICSLI strategy achieves the best result of 83.03% specificity and 76.36% sensitivity. When higher specificity is desired, our method can achieve 90% specificity with 62.12% sensitivity.

Higher Education Counts: Achieving Results. 2007 Executive Summary

ERIC Educational Resources Information Center

Connecticut Department of Higher Education (NJ1), 2007

2007-01-01

"Higher Education Counts" is the annual accountability report on Connecticut's system of higher education. Since 2000, the report has been the primary vehicle for reporting higher education's progress toward achieving six, statutorily-defined state goals: (1) To enhance student learning and promote academic excellence; (2) To join with…

Higher Education Counts: Achieving Results, 2008. Executive Summary

ERIC Educational Resources Information Center

Connecticut Department of Higher Education (NJ1), 2008

2008-01-01

"Higher Education Counts" is the annual accountability report on Connecticut's system of higher education. Since 2000, the report has been the primary vehicle for reporting higher education's progress toward achieving six, statutorily-defined state goals: (1) To enhance student learning and promote academic excellence; (2) To join with…

Higher Education Counts: Achieving Results. 2009 Executive Summary

ERIC Educational Resources Information Center

Connecticut Department of Higher Education (NJ1), 2009

2009-01-01

"Higher Education Counts" is the annual accountability report on Connecticut's system of higher education. Since 2000, the report has been the primary vehicle for reporting higher education's progress toward achieving six, statutorily-defined state goals: (1) To enhance student learning and promote academic excellence; (2) To join with…

Highly Efficient Agrobacterium-Mediated Transformation of Wheat Via In Planta Inoculation

NASA Astrophysics Data System (ADS)

Risacher, Thierry; Craze, Melanie; Bowden, Sarah; Paul, Wyatt; Barsby, Tina

This chapter details a reproducible method for the transformation of spring wheat using Agrobacterium tumefaciens via the direct inoculation of bacteria into immature seeds in planta as described in patent WO 00/63398(1. Transformation efficiencies from 1 to 30% have been obtained and average efficiencies of at least 5% are routinely achieved. Regenerated plants are phenotypically normal with 30-50% of transformation events carrying introduced genes at single insertion sites, a higher rate than is typically reported for transgenic plants produced using biolistic transformation methods.

Hybrid classical/quantum simulation for infrared spectroscopy of water

NASA Astrophysics Data System (ADS)

Maekawa, Yuki; Sasaoka, Kenji; Ube, Takuji; Ishiguro, Takashi; Yamamoto, Takahiro

2018-05-01

We have developed a hybrid classical/quantum simulation method to calculate the infrared (IR) spectrum of water. The proposed method achieves much higher accuracy than conventional classical molecular dynamics (MD) simulations at a much lower computational cost than ab initio MD simulations. The IR spectrum of water is obtained as an ensemble average of the eigenvalues of the dynamical matrix constructed by ab initio calculations, using the positions of oxygen atoms that constitute water molecules obtained from the classical MD simulation. The calculated IR spectrum is in excellent agreement with the experimental IR spectrum.

Validation of an improved 'diffeomorphic demons' algorithm for deformable image registration in image-guided radiation therapy.

PubMed

Zhou, Lu; Zhou, Linghong; Zhang, Shuxu; Zhen, Xin; Yu, Hui; Zhang, Guoqian; Wang, Ruihao

2014-01-01

Deformable image registration (DIR) was widely used in radiation therapy, such as in automatic contour generation, dose accumulation, tumor growth or regression analysis. To achieve higher registration accuracy and faster convergence, an improved 'diffeomorphic demons' registration algorithm was proposed and validated. Based on Brox et al.'s gradient constancy assumption and Malis's efficient second-order minimization (ESM) algorithm, a grey value gradient similarity term and a transformation error term were added into the demons energy function, and a formula was derived to calculate the update of transformation field. The limited Broyden-Fletcher-Goldfarb-Shanno (L-BFGS) algorithm was used to optimize the energy function so that the iteration number could be determined automatically. The proposed algorithm was validated using mathematically deformed images and physically deformed phantom images. Compared with the original 'diffeomorphic demons' algorithm, the registration method proposed achieve a higher precision and a faster convergence speed. Due to the influence of different scanning conditions in fractionated radiation, the density range of the treatment image and the planning image may be different. In such a case, the improved demons algorithm can achieve faster and more accurate radiotherapy.

An Analysis of Mathematics Education Students' Skills in the Process of Programming and Their Practices of Integrating It into Their Teaching

ERIC Educational Resources Information Center

Gökçe, Semirhan; Yenmez, Arzu Aydogan; Özpinar, Ilknur

2017-01-01

Recent developments in technology have changed the learner's profile and the learning outcomes. Today, with the emergence of higher-order thinking skills and computer literacy skills, teaching through traditional methods is likely to fail to achieve the learning outcomes. That is why; teachers and teacher candidates are expected to have computer…

Basic Investigation on Medical Ultrasonic Echo Image Compression by JPEG2000 - Availability of Wavelet Transform and ROI Method

DTIC Science & Technology

2001-10-25

Table III. In spite of the same quality in ROI, it is decided that the images in the cases where QF is 1.3, 1.5 or 2.0 are not good for diagnosis. Of...but (b) is not good for diagnosis by decision of ultrasonographer. Results reveal that wavelet transform achieves higher quality of image compared

Methods and Uses of Classroom Assessments Employed in Teaching Grades Three through Five in Five School Districts in the Mississippi Delta

ERIC Educational Resources Information Center

Burke, Garfield, Jr.; Wang, Ying

2010-01-01

Public school districts in the Mississippi (MS) Delta are under severe pressure to make rapid and adaptable changes in response to the federal legislation No Child Left Behind Act of 2001 and the MS Plan for Student Achievement: Assessment, Accreditation, and Accountability. These reform Acts require higher student performance standards and new…

WWC Review of the Report "Learning the Control of Variables Strategy in Higher and Lower Achieving Classrooms: Contributions of Explicit Instruction and Experimentation"

ERIC Educational Resources Information Center

What Works Clearinghouse, 2012

2012-01-01

The study reviewed in this paper examined three separate methods for teaching the "control of variables strategy" ("CVS"), a procedure for conducting a science experiment so that only one variable is tested and all others are held constant, or "controlled." The study analyzed data from a randomized controlled trial of…

Predictors of cultural capital on science academic achievement at the 8th grade level

NASA Astrophysics Data System (ADS)

Misner, Johnathan Scott

The purpose of the study was to determine if students' cultural capital is a significant predictor of 8th grade science achievement test scores in urban locales. Cultural capital refers to the knowledge used and gained by the dominant class, which allows social and economic mobility. Cultural capital variables include magazines at home and parental education level. Other variables analyzed include socioeconomic status (SES), gender, and English language learners (ELL). This non-experimental study analyzed the results of the 2011 Eighth Grade Science National Assessment of Educational Progress (NAEP). The researcher analyzed the data using a multivariate stepwise regression analysis. The researcher concluded that the addition of cultural capital factors significantly increased the predictive power of the model where magazines in home, gender, student classified as ELL, parental education level, and SES were the independent variables and science achievement was the dependent variable. For alpha=0.05, the overall test for the model produced a R2 value of 0.232; therefore the model predicted 23.2% of variance in science achievement results. Other major findings include: higher measures of home resources predicted higher 2011 NAEP eighth grade science achievement; males were predicted to have higher 2011 NAEP 8 th grade science achievement; classified ELL students were predicted to score lower on the NAEP eight grade science achievement; higher parent education predicted higher NAEP eighth grade science achievement; lower measures of SES predicted lower 2011 NAEP eighth grade science achievement. This study contributed to the research in this field by identifying cultural capital factors that have been found to have statistical significance on predicting eighth grade science achievement results, which can lead to strategies to help improve science academic achievement among underserved populations.

Comparison of the DNA extraction methods for polymerase chain reaction amplification from formalin-fixed and paraffin-embedded tissues.

PubMed

Sato, Y; Sugie, R; Tsuchiya, B; Kameya, T; Natori, M; Mukai, K

2001-12-01

To obtain an adequate quality and quantity of DNA from formalin-fixed and paraffin-embedded tissue, six different DNA extraction methods were compared. Four methods used deparaffinization by xylene followed by proteinase K digestion and phenol-chloroform extraction. The temperature of the different steps was changed to obtain higher yields and improved quality of extracted DNA. The remaining two methods used microwave heating for deparaffinization. The best DNA extraction method consisted of deparaffinization by microwave irradiation, protein digestion with proteinase K at 48 degrees C overnight, and no further purification steps. By this method, the highest DNA yield was obtained and the amplification of a 989-base pair beta-globin gene fragment was achieved. Furthermore, DNA extracted by means of this procedure from five gastric carcinomas was successfully used for single strand conformation polymorphism and direct sequencing assays of the beta-catenin gene. Because the microwave-based DNA extraction method presented here is simple, has a lower contamination risk, and results in a higher yield of DNA compared with the ordinary organic chemical reagent-based extraction method, it is considered applicable to various clinical and basic fields.

Bovine and porcine heparins: different drugs with similar effects on human haemodialysis

PubMed Central

2013-01-01

Background Heparins from porcine and bovine intestinal mucosa differ in their structure and also in their effects on coagulation, thrombosis and bleeding. However, they are used as undistinguishable drugs. Methods We compared bovine and porcine intestinal heparin administered to patients undergoing a particular protocol of haemodialysis. We compared plasma concentrations of these two drugs and also evaluated how they affect patients and the dialyzer used. Results Compared with porcine heparin, bovine heparin achieved only 76% of the maximum plasma concentration as IU mL-1. This observation is consistent with the activities observed in the respective pharmaceutical preparations. When the plasma concentrations were expressed on weight basis, bovine heparin achieved a maximum concentration 1.5 fold higher than porcine heparin. The reduced anticoagulant activity and higher concentration, on weight basis, achieved in the plasma of patients under dialysis using bovine instead of porcine heparin did not affect significantly the patients or the dialyzer used. The heparin dose is still in a range, which confers security and safety to the patients. Discussion Despite no apparent difference between bovine and porcine intestinal heparins in the haemodialysis practice, these two types of heparins should be used as distinct drugs due to their differences in structure and biological effects. Conclusions The reduced anticoagulant activity achieved in the plasma of patients under dialysis using bovine instead of porcine heparin did not affect significantly the patients or the dialyzer. PMID:23763719

Physics issues in diffraction limited storage ring design

NASA Astrophysics Data System (ADS)

Fan, Wei; Bai, ZhengHe; Gao, WeiWei; Feng, GuangYao; Li, WeiMin; Wang, Lin; He, DuoHui

2012-05-01

Diffraction limited electron storage ring is considered a promising candidate for future light sources, whose main characteristics are higher brilliance, better transverse coherence and better stability. The challenge of diffraction limited storage ring design is how to achieve the ultra low beam emittance with acceptable nonlinear performance. Effective linear and nonlinear parameter optimization methods based on Artificial Intelligence were developed for the storage ring physical design. As an example of application, partial physical design of HALS (Hefei Advanced Light Source), which is a diffraction limited VUV and soft X-ray light source, was introduced. Severe emittance growth due to the Intra Beam Scattering effect, which is the main obstacle to achieve ultra low emittance, was estimated quantitatively and possible cures were discussed. It is inspiring that better performance of diffraction limited storage ring can be achieved in principle with careful parameter optimization.

High temperature sensing using higher-order-mode rejected sapphire-crystal fiber gratings

NASA Astrophysics Data System (ADS)

Zhan, Chun; Kim, Jae Hun; Lee, Jon; Yin, Stuart; Ruffin, Paul; Luo, Claire

2007-09-01

In this paper, we report the fabrication of higher-order-mode rejected fiber Bragg gratings (FBGs) in sapphire crystal fiber using infrared (IR) femtosecond laser illumination. The grating is tested in high temperature furnace up to 1600 degree Celsius. As sapphire fiber is only available as highly multimode fiber, a scheme to filter out higher order modes in favor for the fundamental mode is theoretically evaluated and experimentally demonstrated. The approach is to use an ultra thin sapphire crystal fiber (60 micron in diameter) to decrease the number of modes. The small diameter fiber also enables bending the fiber to certain radius which is carefully chosen to provide low loss for the fundamental mode LP01 and high loss for the other high-order modes. After bending, less-than-2-nm resonant peak bandwidth is achieved. The grating spectrum is improved, and higher resolution sensing measurement can be achieved. This mode filtering method is very easy to implement. Furthermore, the sapphire fiber is sealed with hi-purity alumina ceramic cement inside a flexible high temperature titanium tube, and the highly flexible titanium tube offers a robust packaging to sapphire fiber. Our high temperature sapphire grating sensor is very promising in extremely high temperature sensing application.

Supercritical antisolvent versus coevaporation: preparation and characterization of solid dispersions.

PubMed

Majerik, Viktor; Horváth, Géza; Szokonya, László; Charbit, Gérard; Badens, Elisabeth; Bosc, Nathalie; Teillaud, Eric

2007-09-01

The objective of this work was to improve the dissolution rate and aqueous solubility of oxeglitazar. Solid dispersions of oxeglitazar in PVP K17 (polyvinilpyrrolidone) and poloxamer 407 (polyoxyethylene-polyoxypropylene block copolymer) were prepared by supercritical antisolvent (SAS) and coevaporation (CoE) methods. Drug-carrier formulations were characterized by powder X-ray diffraction, Fourier transform infrared spectroscopy, scanning electron microscopy, gas chromatography, UV/VIS spectroscopy and in vitro dissolution tests. The highest dissolution rate (nearly 3-fold higher than raw drug) was achieved by preparation of drug/PVP K17 coevaporate. Oxeglitazar/PVP K17 solid dispersions were stabilized by hydrogen bonding but contained higher amount of residual dichloromethane (DCM) than poloxamer 407 formulations regardless of the method of preparation. SAS prepared oxeglitazar/poloxamer 407 dissolved more than two times faster than raw drug. However, unlike PVP K17, poloxamer 407 did not form a single phase amorphous solid solution with oxeglitazar which has been manifested in higher degrees of crystallinity, too. Among the two techniques, evaluated in this work, conventional coevaporation resulted in higher amorphous content but SAS reduced residual solvent content more efficiently.

Influences of Social and Style Variables on Adult Usage of African American English Features

PubMed Central

Craig, Holly K.; Grogger, Jeffrey T.

2013-01-01

Purpose In this study, the authors examined the influences of selected social (gender, employment status, educational achievement level) and style variables (race of examiner, interview topic) on the production of African American English (AAE) by adults. Method Participants were 50 African American men and women, ages 20–30 years. The authors used Rapid and Anonymous Survey (RAS) methods to collect responses to questions on informal situational and formal message-oriented topics in a short interview with an unacquainted interlocutor. Results Results revealed strong systematic effects for academic achievement, but not gender or employment status. Most features were used less frequently by participants with higher educational levels, but sharp declines in the usage of 5 specific features distinguished the participants differing in educational achievement. Strong systematic style effects were found for the 2 types of questions, but not race of addressee. The features that were most commonly used across participants—copula absence, variable subject–verb agreement, and appositive pronouns—were also the features that showed the greatest style shifting. Conclusions The findings lay a foundation with mature speakers for rate-based and feature inventory methods recently shown to be informative for the study of child AAE and demonstrate the benefits of the RAS. PMID:22361105

Transformation of metal-organic frameworks for molecular sieving membranes

PubMed Central

Li, Wanbin; Zhang, Yufan; Zhang, Congyang; Meng, Qin; Xu, Zehai; Su, Pengcheng; Li, Qingbiao; Shen, Chong; Fan, Zheng; Qin, Lei; Zhang, Guoliang

2016-01-01

The development of simple, versatile strategies for the synthesis of metal-organic framework (MOF)-derived membranes are of increasing scientific interest, but challenges exist in understanding suitable fabrication mechanisms. Here we report a route for the complete transformation of a series of MOF membranes and particles, based on multivalent cation substitution. Through our approach, the effective pore size can be reduced through the immobilization of metal salt residues in the cavities, and appropriate MOF crystal facets can be exposed, to achieve competitive molecular sieving capabilities. The method can also be used more generally for the synthesis of a variety of MOF membranes and particles. Importantly, we design and synthesize promising MOF membranes candidates that are hard to achieve through conventional methods. For example, our CuBTC/MIL-100 membrane exhibits 89, 171, 241 and 336 times higher H2 permeance than that of CO2, O2, N2 and CH4, respectively. PMID:27090597

Comparing monolithic and fused core HPLC columns for fast chromatographic analysis of fat-soluble vitamins.

PubMed

Kurdi, Said El; Muaileq, Dina Abu; Alhazmi, Hassan A; Bratty, Mohammed Al; Deeb, Sami El

2017-06-27

HPLC stationary phases of monolithic and fused core type can be used to achieve fast chromatographic separation as an alternative to UPLC. In this study, monolithic and fused core stationary phases are compared for fast separation of four fat-soluble vitamins. Three new methods on the first and second generation monolithic silica RP-18e columns and a fused core pentafluoro-phenyl propyl column were developed. Application of three fused core columns offered comparable separations of retinyl palmitate, DL-α-tocopheryl acetate, cholecalciferol and menadione in terms of elution speed and separation efficiency. Separation was achieved in approx. 5 min with good resolution (Rs > 5) and precision (RSD ≤ 0.6 %). Monolithic columns showed, however, a higher number of theoretical plates, better precision and lower column backpressure than the fused core column. The three developed methods were successfully applied to separate and quantitate fat-soluble vitamins in commercial products.

Achieving a high mode count in the exact electromagnetic simulation of diffractive optical elements.

PubMed

Junker, André; Brenner, Karl-Heinz

2018-03-01

The application of rigorous optical simulation algorithms, both in the modal as well as in the time domain, is known to be limited to the nano-optical scale due to severe computing time and memory constraints. This is true even for today's high-performance computers. To address this problem, we develop the fast rigorous iterative method (FRIM), an algorithm based on an iterative approach, which, under certain conditions, allows solving also large-size problems approximation free. We achieve this in the case of a modal representation by avoiding the computationally complex eigenmode decomposition. Thereby, the numerical cost is reduced from O(N 3 ) to O(N log N), enabling a simulation of structures like certain diffractive optical elements with a significantly higher mode count than presently possible. Apart from speed, another major advantage of the iterative FRIM over standard modal methods is the possibility to trade runtime against accuracy.

Silicon Sheet Growth Development for the Large Area Sheet Task of the Low Cost Solar Array Project. Heat Exchanger Method - Ingot Casting Fixed Abrasive Method - Multi-Wire Slicing

NASA Technical Reports Server (NTRS)

Schmid, F.; Khattak, C. P.

1978-01-01

Solar cells fabricated from HEM cast silicon yielded up to 15% conversion efficiencies. This was achieved in spite of using unpurified graphite parts in the HEM furnace and without optimization of material or cell processing parameters. Molybdenum retainers prevented SiC formation and reduced carbon content by 50%. The oxygen content of vacuum cast HEM silicon is lower than typical Czochralski grown silicon. Impregnation of 45 micrometers diamonds into 7.5 micrometers copper sheath showed distortion of the copper layer. However, 12.5 micrometers and 15 micrometers copper sheath can be impregnated with 45 micrometers diamonds to a high concentration. Electroless nickel plating of wires impregnated only in the cutting edge showed nickel concentration around the diamonds. This has the possibility of reducing kerf. The high speed slicer fabricated can achieve higher speed and longer stroke with vibration isolation.

The performance evaluation model of mining project founded on the weight optimization entropy value method

NASA Astrophysics Data System (ADS)

Mao, Chao; Chen, Shou

2017-01-01

According to the traditional entropy value method still have low evaluation accuracy when evaluating the performance of mining projects, a performance evaluation model of mineral project founded on improved entropy is proposed. First establish a new weight assignment model founded on compatible matrix analysis of analytic hierarchy process (AHP) and entropy value method, when the compatibility matrix analysis to achieve consistency requirements, if it has differences between subjective weights and objective weights, moderately adjust both proportions, then on this basis, the fuzzy evaluation matrix for performance evaluation. The simulation experiments show that, compared with traditional entropy and compatible matrix analysis method, the proposed performance evaluation model of mining project based on improved entropy value method has higher accuracy assessment.

Examining the Academic Achievement-Delinquency Relationship Among Southeast Asian Americans.

PubMed

Bui, Laura

2018-05-01

The extent to which poor academic achievement is strongly related to delinquency among Southeast Asian Americans (SEAA) remains unclear; reasons are methodological limitations and aggregated findings for Asian Americans, which mask evidence that SEAA have a higher prevalence of criminality and poor academic performance than other Asian American groups. The present study examines the academic achievement-delinquency relationship in a diverse group of 1,214 SEAA using data from the Children of Immigrants Longitudinal Study (CILS). Propensity score matching (PSM) was used to make causal inferences and assess whether poor academic achieving SEAA, after being matched with higher academic achieving SEAA, displayed a higher prevalence of delinquency. Findings showed that, even after matching, poor academic achieving SEAA were still more likely to exhibit delinquent behavior than those who performed academically better. Interventions targeting SEAA communities will need to focus more on improving academic achievement to directly prevent and decrease delinquent behavior.

A review of multivariate methods in brain imaging data fusion

NASA Astrophysics Data System (ADS)

Sui, Jing; Adali, Tülay; Li, Yi-Ou; Yang, Honghui; Calhoun, Vince D.

2010-03-01

On joint analysis of multi-task brain imaging data sets, a variety of multivariate methods have shown their strengths and been applied to achieve different purposes based on their respective assumptions. In this paper, we provide a comprehensive review on optimization assumptions of six data fusion models, including 1) four blind methods: joint independent component analysis (jICA), multimodal canonical correlation analysis (mCCA), CCA on blind source separation (sCCA) and partial least squares (PLS); 2) two semi-blind methods: parallel ICA and coefficient-constrained ICA (CC-ICA). We also propose a novel model for joint blind source separation (BSS) of two datasets using a combination of sCCA and jICA, i.e., 'CCA+ICA', which, compared with other joint BSS methods, can achieve higher decomposition accuracy as well as the correct automatic source link. Applications of the proposed model to real multitask fMRI data are compared to joint ICA and mCCA; CCA+ICA further shows its advantages in capturing both shared and distinct information, differentiating groups, and interpreting duration of illness in schizophrenia patients, hence promising applicability to a wide variety of medical imaging problems.

Peptide hydrogelation triggered by enzymatic induced pH switch

NASA Astrophysics Data System (ADS)

Cheng, Wei; Li, Ying

2016-07-01

It remains challenging to develop methods that can precisely control the self-assembling kinetics and thermodynamics of peptide hydrogelators to achieve hydrogels with optimal properties. Here we report the hydrogelation of peptide hydrogelators by an enzymatically induced pH switch, which involves the combination of glucose oxidase and catalase with D-glucose as the substrate, in which both the gelation kinetics and thermodynamics can be controlled by the concentrations of D-glucose. This novel hydrogelation method could result in hydrogels with higher mechanical stability and lower hydrogelation concentrations. We further illustrate the application of this hydrogelation method to differentiate different D-glucose levels.

Birefringence Bragg Binary (3B) grating, quasi-Bragg grating and immersion gratings

NASA Astrophysics Data System (ADS)

Ebizuka, Noboru; Morita, Shin-ya; Yamagata, Yutaka; Sasaki, Minoru; Bianco, Andorea; Tanabe, Ayano; Hashimoto, Nobuyuki; Hirahara, Yasuhiro; Aoki, Wako

2014-07-01

A volume phase holographic (VPH) grating achieves high angular dispersion and very high diffraction efficiency for the first diffraction order and for S or P polarization. However the VPH grating could not achieve high diffraction efficiency for non-polarized light at a large diffraction angle because properties of diffraction efficiencies for S and P polarizations are different. Furthermore diffraction efficiency of the VPH grating extinguishes toward a higher diffraction order. A birefringence binary Bragg (3B) grating is a thick transmission grating with optically anisotropic material such as lithium niobate or liquid crystal. The 3B grating achieves diffraction efficiency up to 100% for non-polarized light by tuning of refractive indices for S and P polarizations, even in higher diffraction orders. We fabricated 3B grating with liquid crystal and evaluated the performance of the liquid crystal grating. A quasi-Bragg (QB) grating, which consists long rectangle mirrors aligned in parallel precisely such as a window shade, also achieves high diffraction efficiency toward higher orders. We fabricated QB grating by laminating of silica glass substrates and glued by pressure fusion of gold films. A quasi-Bragg immersion (QBI) grating has smooth mirror hypotenuse and reflector array inside the hypotenuse, instead of step-like grooves of a conventional immersion grating. An incident beam of the QBI grating reflects obliquely at a reflector, then reflects vertically at the mirror surface and reflects again at the same reflector. We are going to fabricate QBI gratings by laminating of mirror plates as similar to fabrication of the QB grating. We will also fabricate silicon and germanium immersion gratings with conventional step-like grooves by means of the latest diamond machining methods. We introduce characteristics and performance of these gratings.

Quality evaluation of pansharpened hyperspectral images generated using multispectral images

NASA Astrophysics Data System (ADS)

Matsuoka, Masayuki; Yoshioka, Hiroki

2012-11-01

Hyperspectral remote sensing can provide a smooth spectral curve of a target by using a set of higher spectral resolution detectors. The spatial resolution of the hyperspectral images, however, is generally much lower than that of multispectral images due to the lower energy of incident radiation. Pansharpening is an image-fusion technique that generates higher spatial resolution multispectral images by combining lower resolution multispectral images with higher resolution panchromatic images. In this study, higher resolution hyperspectral images were generated by pansharpening of simulated lower hyperspectral and higher multispectral data. Spectral and spatial qualities of pansharpened images, then, were accessed in relation to the spectral bands of multispectral images. Airborne hyperspectral data of AVIRIS was used in this study, and it was pansharpened using six methods. Quantitative evaluations of pansharpened image are achieved using two frequently used indices, ERGAS, and the Q index.

Controlling the joint local false discovery rate is more powerful than meta-analysis methods in joint analysis of summary statistics from multiple genome-wide association studies.

PubMed

Jiang, Wei; Yu, Weichuan

2017-02-15

In genome-wide association studies (GWASs) of common diseases/traits, we often analyze multiple GWASs with the same phenotype together to discover associated genetic variants with higher power. Since it is difficult to access data with detailed individual measurements, summary-statistics-based meta-analysis methods have become popular to jointly analyze datasets from multiple GWASs. In this paper, we propose a novel summary-statistics-based joint analysis method based on controlling the joint local false discovery rate (Jlfdr). We prove that our method is the most powerful summary-statistics-based joint analysis method when controlling the false discovery rate at a certain level. In particular, the Jlfdr-based method achieves higher power than commonly used meta-analysis methods when analyzing heterogeneous datasets from multiple GWASs. Simulation experiments demonstrate the superior power of our method over meta-analysis methods. Also, our method discovers more associations than meta-analysis methods from empirical datasets of four phenotypes. The R-package is available at: http://bioinformatics.ust.hk/Jlfdr.html . eeyu@ust.hk. Supplementary data are available at Bioinformatics online. © The Author 2016. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com

Barriers to Blacks' Educational Achievement in Higher Education: A Statistical and Conceptual Review.

ERIC Educational Resources Information Center

Lang, Marvel

1992-01-01

Examines trends in the educational achievement of African Americans at secondary and postsecondary levels using data from various national surveys. Barriers to educational achievement are described, and intervention strategies for improving African-American success in higher education are reviewed. Increasing minority participation will require…

Identifying a parsimonious model for predicting academic achievement in undergraduate medical education: A confirmatory factor analysis

PubMed Central

Ali, Syeda Kauser; Baig, Lubna Ansari; Violato, Claudio; Zahid, Onaiza

2017-01-01

Objectives: This study was conducted to adduce evidence of validity for admissions tests and processes and for identifying a parsimonious model that predicts students’ academic achievement in Medical College. Methods: Psychometric study done on admission data and assessment scores for five years of medical studies at Aga Khan University Medical College, Pakistan using confirmatory factor analysis (CFA) and structured equation modeling (SEM). Sample included 276 medical students admitted in 2003, 2004 and 2005. Results: The SEM supported the existence of covariance between verbal reasoning, science and clinical knowledge for predicting achievement in medical school employing Maximum Likelihood (ML) estimations (n=112). Fit indices: χ2 (21) = 59.70, p =<.0001; CFI=.873; RMSEA = 0.129; SRMR = 0.093. Conclusions: This study shows that in addition to biology and chemistry which have been traditionally used as major criteria for admission to medical colleges in Pakistan; mathematics has proven to be a better predictor for higher achievements in medical college. PMID:29067063

Can learning style predict student satisfaction with different instruction methods and academic achievement in medical education?

PubMed

Gurpinar, Erol; Alimoglu, Mustafa Kemal; Mamakli, Sumer; Aktekin, Mehmet

2010-12-01

The curriculum of our medical school has a hybrid structure including both traditional training (lectures) and problem-based learning (PBL) applications. The purpose of this study was to determine the learning styles of our medical students and investigate the relation of learning styles with each of satisfaction with different instruction methods and academic achievement in them. This study was carried out with the participation of 170 first-year medical students (the participation rate was 91.4%). The researchers prepared sociodemographic and satisfaction questionnaires to determine the characteristics of the participants and their satisfaction levels with traditional training and PBL. The Kolb learning styles inventory was used to explore the learning styles of the study group. The participants completed all forms at the end of the first year of medical education. Indicators of academic achievement were scores of five theoretical block exams and five PBL exams performed throughout the academic year of 2008-2009. The majority of the participants took part in the "diverging" (n = 84, 47.7%) and "assimilating" (n = 73, 41.5%) groups. Numbers of students in the "converging" and "accommodating" groups were 11 (6.3%) and 8 (4.5%), respectively. In all learning style groups, PBL satisfaction scores were significantly higher than those of traditional training. Exam scores for "PBL and traditional training" did not differ among the four learning styles. In logistic regression analysis, learning style (assimilating) predicted student satisfaction with traditional training and success in theoretical block exams. Nothing predicted PBL satisfaction and success. This is the first study conducted among medical students evaluating the relation of learning style with student satisfaction and academic achievement. More research with larger groups is needed to generalize our results. Some learning styles may relate to satisfaction with and achievement in some instruction methods.

Outcomes of a 4-year program with higher education and employment goals for individuals diagnosed with mental illness.

PubMed

Schindler, Victoria P; Sauerwald, Camille

2013-01-01

This study examined outcomes of the first four years (2005-2009) of the Bridge Program, an occupational therapy (OT) program that incorporates principles of supported education and supported employment. This program was developed to assist individuals with mental illness to achieve higher education and employment goals. Forty-eight adult participants with various mental health diagnoses. A quantitative one-group pretest-posttest survey design and posttest qualitative focus groups were used. Participants enrolled in higher education increased from 7 to 11 (pretest=15%; posttest=23%), participants employed increased from 5 to 19 (pretest=10%; posttest=40%), and the combined category of higher education/employment increased from 12 to 30 (pretest=25%; posttest=63%) Statistical significance was achieved from pre to posttest in the employment sample (p<0.000), and in the combined sample of higher education/employment (p< 0.000), but was not achieved in the higher education sample from pre to posttest (p=0.125). Quantitative and qualitative results support that an OT program incorporating principles of supported education and employment can assist individuals with mental illness to achieve higher education and employment goals. Results also outlined items participants found to be supports and barriers to achieving goals.

Breast mass segmentation in mammography using plane fitting and dynamic programming.

PubMed

Song, Enmin; Jiang, Luan; Jin, Renchao; Zhang, Lin; Yuan, Yuan; Li, Qiang

2009-07-01

Segmentation is an important and challenging task in a computer-aided diagnosis (CAD) system. Accurate segmentation could improve the accuracy in lesion detection and characterization. The objective of this study is to develop and test a new segmentation method that aims at improving the performance level of breast mass segmentation in mammography, which could be used to provide accurate features for classification. This automated segmentation method consists of two main steps and combines the edge gradient, the pixel intensity, as well as the shape characteristics of the lesions to achieve good segmentation results. First, a plane fitting method was applied to a background-trend corrected region-of-interest (ROI) of a mass to obtain the edge candidate points. Second, dynamic programming technique was used to find the "optimal" contour of the mass from the edge candidate points. Area-based similarity measures based on the radiologist's manually marked annotation and the segmented region were employed as criteria to evaluate the performance level of the segmentation method. With the evaluation criteria, the new method was compared with 1) the dynamic programming method developed by Timp and Karssemeijer, and 2) the normalized cut segmentation method, based on 337 ROIs extracted from a publicly available image database. The experimental results indicate that our segmentation method can achieve a higher performance level than the other two methods, and the improvements in segmentation performance level were statistically significant. For instance, the mean overlap percentage for the new algorithm was 0.71, whereas those for Timp's dynamic programming method and the normalized cut segmentation method were 0.63 (P < .001) and 0.61 (P < .001), respectively. We developed a new segmentation method by use of plane fitting and dynamic programming, which achieved a relatively high performance level. The new segmentation method would be useful for improving the accuracy of computerized detection and classification of breast cancer in mammography.

Workshop on Jet Exhaust Noise Reduction for Tactical Aircraft - NASA Perspective

NASA Technical Reports Server (NTRS)

Huff, Dennis L.; Henderson, Brenda S.

2007-01-01

Jet noise from supersonic, high performance aircraft is a significant problem for takeoff and landing operations near air bases and aircraft carriers. As newer aircraft with higher thrust and performance are introduced, the noise tends to increase due to higher jet exhaust velocities. Jet noise has been a subject of research for over 55 years. Commercial subsonic aircraft benefit from changes to the engine cycle that reduce the exhaust velocities and result in significant noise reduction. Most of the research programs over the past few decades have concentrated on commercial aircraft. Progress has been made by introducing new engines with design features that reduce the noise. NASA has recently started a new program called "Fundamental Aeronautics" where three projects (subsonic fixed wing, subsonic rotary wing, and supersonics) address aircraft noise. For the supersonics project, a primary goal is to understand the underlying physics associated with jet noise so that improved noise prediction tools and noise reduction methods can be developed for a wide range of applications. Highlights from the supersonics project are presented including prediction methods for broadband shock noise, flow measurement methods, and noise reduction methods. Realistic expectations are presented based on past history that indicates significant jet noise reduction cannot be achieved without major changes to the engine cycle. NASA s past experience shows a few EPNdB (effective perceived noise level in decibels) can be achieved using low noise design features such as chevron nozzles. Minimal thrust loss can be expected with these nozzles (< 0.5%) and they may be retrofitted on existing engines. In the long term, it is desirable to use variable cycle engines that can be optimized for lower jet noise during takeoff operations and higher thrust for operational performance. It is also suggested that noise experts be included early in the design process for engine nozzle systems to participate in decisions that may impact the jet noise.

[A retrieval method of drug molecules based on graph collapsing].

PubMed

Qu, J W; Lv, X Q; Liu, Z M; Liao, Y; Sun, P H; Wang, B; Tang, Z

2018-04-18

To establish a compact and efficient hypergraph representation and a graph-similarity-based retrieval method of molecules to achieve effective and efficient medicine information retrieval. Chemical structural formula (CSF) was a primary search target as a unique and precise identifier for each compound at the molecular level in the research field of medicine information retrieval. To retrieve medicine information effectively and efficiently, a complete workflow of the graph-based CSF retrieval system was introduced. This system accepted the photos taken from smartphones and the sketches drawn on tablet personal computers as CSF inputs, and formalized the CSFs with the corresponding graphs. Then this paper proposed a compact and efficient hypergraph representation for molecules on the basis of analyzing factors that directly affected the efficiency of graph matching. According to the characteristics of CSFs, a hierarchical collapsing method combining graph isomorphism and frequent subgraph mining was adopted. There was yet a fundamental challenge, subgraph overlapping during the collapsing procedure, which hindered the method from establishing the correct compact hypergraph of an original CSF graph. Therefore, a graph-isomorphism-based algorithm was proposed to select dominant acyclic subgraphs on the basis of overlapping analysis. Finally, the spatial similarity among graphical CSFs was evaluated by multi-dimensional measures of similarity. To evaluate the performance of the proposed method, the proposed system was firstly compared with Wikipedia Chemical Structure Explorer (WCSE), the state-of-the-art system that allowed CSF similarity searching within Wikipedia molecules dataset, on retrieval accuracy. The system achieved higher values on mean average precision, discounted cumulative gain, rank-biased precision, and expected reciprocal rank than WCSE from the top-2 to the top-10 retrieved results. Specifically, the system achieved 10%, 1.41, 6.42%, and 1.32% higher than WCSE on these metrics for top-10 retrieval results, respectively. Moreover, several retrieval cases were presented to intuitively compare with WCSE. The results of the above comparative study demonstrated that the proposed method outperformed the existing method with regard to accuracy and effectiveness. This paper proposes a graph-similarity-based retrieval approach for medicine information. To obtain satisfactory retrieval results, an isomorphism-based algorithm is proposed for dominant subgraph selection based on the subgraph overlapping analysis, as well as an effective and efficient hypergraph representation of molecules. Experiment results demonstrate the effectiveness of the proposed approach.

A sub-space greedy search method for efficient Bayesian Network inference.

PubMed

Zhang, Qing; Cao, Yong; Li, Yong; Zhu, Yanming; Sun, Samuel S M; Guo, Dianjing

2011-09-01

Bayesian network (BN) has been successfully used to infer the regulatory relationships of genes from microarray dataset. However, one major limitation of BN approach is the computational cost because the calculation time grows more than exponentially with the dimension of the dataset. In this paper, we propose a sub-space greedy search method for efficient Bayesian Network inference. Particularly, this method limits the greedy search space by only selecting gene pairs with higher partial correlation coefficients. Using both synthetic and real data, we demonstrate that the proposed method achieved comparable results with standard greedy search method yet saved ∼50% of the computational time. We believe that sub-space search method can be widely used for efficient BN inference in systems biology. Copyright © 2011 Elsevier Ltd. All rights reserved.

Disinfection of wastewater by hydrogen peroxide or peracetic acid: development of procedures for measurement of residual disinfectant and application to a physicochemically treated municipal effluent.

PubMed

Wagner, Monika; Brumelis, Daina; Gehr, Ronald

2002-01-01

The Montreal Urban Community Wastewater Treatment Plant (MUCWTP) located in Montreal. Quebec, Canada, uses physicochemical treatment processes prior to discharging wastewater into the St. Lawrence River via an outfall tunnel of 2 hours retention time. Although chlorination facilities exist, they are not being used, and the MUCWTP is seeking alternative methods for disinfection to achieve a 2- to 3-log fecal coliform reduction. Liquid chemical disinfectants were attractive options because of their low capital costs. This led to an investigation of the feasibility of using hydrogen peroxide or peracetic acid. A method for measuring peroxycompounds (hydrogen peroxide or peracetic acid plus hydrogen peroxide) was developed using the peroxidase-based oxidation of 2,2'-azino-bis(3-ethylbenz-thiazoline-6-sulfuric acid) diammonium salt (ABTS) with hydrogen peroxide. The validity of the method was confirmed using effluent from the MUCWTP. Recovery was higher than 90% for peracetic acid levels as low as 1.0 mg/L. Quenching of hydrogen peroxide was achieved with 50-mg/L catalase; quenching of peracetic acid was achieved with 100 mg/L of sodium thiosulfate, followed by 50 mg/L of catalase. Batch disinfection tests were conducted on MUCWTP effluent. Hydrogen peroxide and peracetic acid in wastewater over time could be modeled as a second-order decay, with the decay "constant" being a function of the initial concentration of peroxycompounds. This function was the same for both hydrogen peroxide and peracetic acid, possibly indicating similar decomposition pathways in wastewater matrices. Disinfection was modeled using a modified Hom equation. Required doses of hydrogen peroxide to reach the target fecal coliform levels ranged from 106 to 285 mg/L, with the higher doses occurring when ferric chloride instead of alum was used as the coagulant. Hence, hydrogen peroxide was infeasible as a disinfectant for this application. On the other hand, the peracetic acid dose needed to achieve the target fecal coliform level was only 0.6 to 1.6 mg/L. Therefore, peracetic acid seems to be a promising disinfectant for physicochemical or primary effluent, or combined sewer overflows.

Radiotherapy dose–response analysis for diffuse large B-cell lymphoma with a complete response to chemotherapy

PubMed Central

2012-01-01

Objective To examine the efficacy of different radiation doses after achievement of a complete response to chemotherapy in diffuse large B-cell lymphoma (DLBCL). Methods Patients with stage I-IV DLBCL treated from 1995–2009 at Duke Cancer Institute who achieved a complete response to chemotherapy were reviewed. In-field control, event-free survival, and overall survival were calculated using the Kaplan-Meier method. Dose response was evaluated by grouping treated sites by delivered radiation dose. Results 105 patients were treated with RT to 214 disease sites. Chemotherapy (median 6 cycles) was R-CHOP (65%), CHOP (26%), R-CNOP (2%), or other (7%). Post-chemotherapy imaging was PET/CT (88%), gallium with CT (1%), or CT only (11%). The median RT dose was 30 Gy (range, 12–40 Gy). The median radiation dose was higher for patients with stage I-II disease compared with patients with stage III-IV disease (30 versus 24.5 Gy, p < 0.001). Five-year in-field control, event-free survival, and overall survival for all patients was 94% (95% CI: 89-99%), 84% (95% CI: 77-92%), and 91% (95% CI: 85-97%), respectively. Six patients developed an in-field recurrence at 10 sites, without a clear dose response. In-field failure was higher at sites ≥ 10 cm (14% versus 4%, p = 0.06). Conclusion In-field control was excellent with a combined modality approach when a complete response was achieved after chemotherapy without a clear radiation dose response. PMID:22720801

Cultural capital in context: heterogeneous returns to cultural capital across schooling environments.

PubMed

Andersen, Ida Gran; Jæger, Mads Meier

2015-03-01

This paper tests two competing explanations of differences in returns to cultural capital across schooling environments: Cultural reproduction (cultural capital yields a higher returns in high-achieving environments than in low-achieving ones) and cultural mobility (cultural capital yields higher returns in low-achieving environments). Using multilevel mixture models, empirical results from analyses based on PISA data from three countries (Canada, Germany, and Sweden) show that returns to cultural capital tend to be higher in low-achieving schooling environments than in high-achieving ones. These results principally support the cultural mobility explanation and suggest that research should pay explicit attention to the institutional contexts in which cultural capital is converted into educational success. Copyright © 2014 Elsevier Inc. All rights reserved.

Study on Cloud Security Based on Trust Spanning Tree Protocol

NASA Astrophysics Data System (ADS)

Lai, Yingxu; Liu, Zenghui; Pan, Qiuyue; Liu, Jing

2015-09-01

Attacks executed on Spanning Tree Protocol (STP) expose the weakness of link layer protocols and put the higher layers in jeopardy. Although the problems have been studied for many years and various solutions have been proposed, many security issues remain. To enhance the security and credibility of layer-2 network, we propose a trust-based spanning tree protocol aiming at achieving a higher credibility of LAN switch with a simple and lightweight authentication mechanism. If correctly implemented in each trusted switch, the authentication of trust-based STP can guarantee the credibility of topology information that is announced to other switch in the LAN. To verify the enforcement of the trusted protocol, we present a new trust evaluation method of the STP using a specification-based state model. We implement a prototype of trust-based STP to investigate its practicality. Experiment shows that the trusted protocol can achieve security goals and effectively avoid STP attacks with a lower computation overhead and good convergence performance.

Step-by-Step Heating of Dye Solution for Efficient Solar Energy Harvesting in Dye-Sensitized Solar Cells

NASA Astrophysics Data System (ADS)

Shah, Syed Afaq Ali; Sayyad, Muhammad Hassan; Abdulkarim, Salem; Qiao, Qiquan

2018-05-01

A step-by-step heat treatment was applied to ruthenium-based N719 dye solution for its potential application in dye-sensitized solar cells (DSSCs). The effects were analyzed and compared with standard untreated devices. A significant increase in short circuit current density was observed by employing a step-by-step heating method for dye solution in DSSCs. This increase of J sc is attributed to the enhancement in dye adsorption by the surface of the semiconductor and the higher number of charge carriers generated. DSSCs fabricated by a heated dye solution have achieved an overall power conversion efficiency of 8.41% which is significantly higher than the efficiency of 7.31% achieved with DSSCs fabricated without heated dye. Electrochemical impedance spectroscopy and capacitance voltage studies were performed to understand the better performance of the device fabricated with heated dye. Furthermore, transient photocurrent and transient photovoltage measurements were also performed to gain an insight into interfacial charge carrier recombinations.

Functional brain organization of working memory in adolescents varies in relation to family income and academic achievement.

PubMed

Finn, Amy S; Minas, Jennifer E; Leonard, Julia A; Mackey, Allyson P; Salvatore, John; Goetz, Calvin; West, Martin R; Gabrieli, Christopher F O; Gabrieli, John D E

2017-09-01

Working memory (WM) capacity reflects executive functions associated with performance on a wide range of cognitive tasks and education outcomes, including mathematics achievement, and is associated with dorsolateral prefrontal and parietal cortices. Here we asked if family income is associated with variation in the functional brain organization of WM capacity among adolescents, and whether that variation is associated with performance on a statewide test of academic achievement in mathematics. Participants were classified into higher-income and lower-income groups based on family income, and performed a WM task with a parametric manipulation of WM load (N-back task) during functional magnetic resonance imaging (fMRI). Behaviorally, the higher-income group had greater WM capacity and higher mathematics achievement scores. Neurally, the higher-income group showed greater activation as a function of WM load in bilateral prefrontal, parietal, and other regions, although the lower-income group exhibited greater activation at the lowest load. Both groups exhibited positive correlations between parietal activations and mathematics achievement scores, but only the higher-income group exhibited a positive correlation between prefrontal activations and mathematics scores. Most of these findings were maintained when higher- and lower-income groups were matched on WM task performance or nonverbal IQ. Findings indicate that the functional neural architecture of WM varies with family income and is associated with education measures of mathematics achievement. © 2016 John Wiley & Sons Ltd.

Cluster (School) RCT of ParentCorps: Impact on Kindergarten Academic Achievement

PubMed Central

Dawson-McClure, Spring; Calzada, Esther J.; Huang, Keng-Yen; Kamboukos, Dimitra; Palamar, Joseph J.; Petkova, Eva

2013-01-01

OBJECTIVE: To evaluate the impact of an early childhood, family-centered, school-based intervention on children’s kindergarten academic achievement. METHODS: This was a cluster (school) randomized controlled trial with assessments from pre-kindergarten (pre-k) entry through the end of kindergarten. The setting was 10 public elementary schools with 26 pre-k classes in 2 school districts in urban disadvantaged neighborhoods serving a largely black, low-income population. Participants were 1050 black and Latino, low-income children (age 4; 88% of pre-k population) enrolled in 10 schools over 4 years. Universal intervention aimed to promote self-regulation and early learning by strengthening positive behavior support and effective behavior management at home and school, and increasing parent involvement in education. Intervention included after-school group sessions for families of pre-k students (13 2-hour sessions; co-led by pre-k teachers) and professional development for pre-k and kindergarten teachers. The outcome measures were standardized test scores of kindergarten reading, writing, and math achievement by independent evaluators masked to intervention condition (primary outcome); developmental trajectories of teacher-rated academic performance from pre-k through kindergarten (secondary outcome). RESULTS: Relative to children in control schools, children in intervention schools had higher kindergarten achievement test scores (Cohen’s d = 0.18, mean difference = 2.64, SE = 0.90, P = .03) and higher teacher-rated academic performance (Cohen’s d = 0.25, mean difference = 5.65, SE = 2.34, P = .01). CONCLUSIONS: Early childhood population-level intervention that enhances both home and school environments shows promise to advance academic achievement among minority children from disadvantaged, urban neighborhoods. PMID:23589806

Fuel cells with doped lanthanum gallate electrolyte

NASA Astrophysics Data System (ADS)

Feng, Man; Goodenough, John B.; Huang, Keqin; Milliken, Christopher

Single cells with doped lanthanum gallate electrolyte material were constructed and tested from 600 to 800°C. Both ceria and the electrolyte material were mixed with NiO powder respectively to form composite anodes. Doped lanthanum cobaltite was used exclusively as the cathode material. While high power density from the solid oxide fuel cells at 800°C was achieved. our results clearly indicate that anode overpotential is the dominant factor in the power loss of the cells. Better anode materials and anode processing methods need to be found to fully utilize the high ionic conductivity of the doped lanthanum galiate and achieve higher power density at 800°C from solid oxide fuel cells.

NMR at earth's magnetic field using para-hydrogen induced polarization.

PubMed

Hamans, Bob C; Andreychenko, Anna; Heerschap, Arend; Wijmenga, Sybren S; Tessari, Marco

2011-09-01

A method to achieve NMR of dilute samples in the earth's magnetic field by applying para-hydrogen induced polarization is presented. Maximum achievable polarization enhancements were calculated by numerically simulating the experiment and compared to the experimental results and to the thermal equilibrium in the earth's magnetic field. Simultaneous 19F and 1H NMR detection on a sub-milliliter sample of a fluorinated alkyne at millimolar concentration (∼10(18) nuclear spins) was realized with just one single scan. A highly resolved spectrum with a signal/noise ratio higher than 50:1 was obtained without using an auxiliary magnet or any form of radio frequency shielding. Copyright © 2011 Elsevier Inc. All rights reserved.

Ultrasonic Mixing of Epoxy Curing Agents.

DTIC Science & Technology

1983-05-01

Li~fl , • 4 Future generation aircraft need higher performance polymer matrices to fully achieve the weight savings possible with composite materials...ref. 1). New resins are being formulated in an effort to understand basic polymer behav- ior and to develop improved resins (refs. 2, 3 and 4). Some... polymer /curing agent combinations that could be useful, cannot be mixed properly using conven- tional methods because of the high melting temperature

A deterministic compressive sensing model for bat biosonar.

PubMed

Hague, David A; Buck, John R; Bilik, Igal

2012-12-01

The big brown bat (Eptesicus fuscus) uses frequency modulated (FM) echolocation calls to accurately estimate range and resolve closely spaced objects in clutter and noise. They resolve glints spaced down to 2 μs in time delay which surpasses what traditional signal processing techniques can achieve using the same echolocation call. The Matched Filter (MF) attains 10-12 μs resolution while the Inverse Filter (IF) achieves higher resolution at the cost of significantly degraded detection performance. Recent work by Fontaine and Peremans [J. Acoustic. Soc. Am. 125, 3052-3059 (2009)] demonstrated that a sparse representation of bat echolocation calls coupled with a decimating sensing method facilitates distinguishing closely spaced objects over realistic SNRs. Their work raises the intriguing question of whether sensing approaches structured more like a mammalian auditory system contains the necessary information for the hyper-resolution observed in behavioral tests. This research estimates sparse echo signatures using a gammatone filterbank decimation sensing method which loosely models the processing of the bat's auditory system. The decimated filterbank outputs are processed with [script-l](1) minimization. Simulations demonstrate that this model maintains higher resolution than the MF and significantly better detection performance than the IF for SNRs of 5-45 dB while undersampling the return signal by a factor of six.

Evaluation of smoking prevention television messages based on the elaboration likelihood model

PubMed Central

Flynn, Brian S.; Worden, John K.; Bunn, Janice Yanushka; Connolly, Scott W.; Dorwaldt, Anne L.

2011-01-01

Progress in reducing youth smoking may depend on developing improved methods to communicate with higher risk youth. This study explored the potential of smoking prevention messages based on the Elaboration Likelihood Model (ELM) to address these needs. Structured evaluations of 12 smoking prevention messages based on three strategies derived from the ELM were conducted in classroom settings among a diverse sample of non-smoking middle school students in three states (n = 1771). Students categorized as likely to have higher involvement in a decision to initiate cigarette smoking reported relatively high ratings on a cognitive processing indicator for messages focused on factual arguments about negative consequences of smoking than for messages with fewer or no direct arguments. Message appeal ratings did not show greater preference for this message type among higher involved versus lower involved students. Ratings from students reporting lower academic achievement suggested difficulty processing factual information presented in these messages. The ELM may provide a useful strategy for reaching adolescents at risk for smoking initiation, but particular attention should be focused on lower academic achievers to ensure that messages are appropriate for them. This approach should be explored further before similar strategies could be recommended for large-scale implementation. PMID:21885672

Evaluation of smoking prevention television messages based on the elaboration likelihood model.

PubMed

Flynn, Brian S; Worden, John K; Bunn, Janice Yanushka; Connolly, Scott W; Dorwaldt, Anne L

2011-12-01

Progress in reducing youth smoking may depend on developing improved methods to communicate with higher risk youth. This study explored the potential of smoking prevention messages based on the Elaboration Likelihood Model (ELM) to address these needs. Structured evaluations of 12 smoking prevention messages based on three strategies derived from the ELM were conducted in classroom settings among a diverse sample of non-smoking middle school students in three states (n = 1771). Students categorized as likely to have higher involvement in a decision to initiate cigarette smoking reported relatively high ratings on a cognitive processing indicator for messages focused on factual arguments about negative consequences of smoking than for messages with fewer or no direct arguments. Message appeal ratings did not show greater preference for this message type among higher involved versus lower involved students. Ratings from students reporting lower academic achievement suggested difficulty processing factual information presented in these messages. The ELM may provide a useful strategy for reaching adolescents at risk for smoking initiation, but particular attention should be focused on lower academic achievers to ensure that messages are appropriate for them. This approach should be explored further before similar strategies could be recommended for large-scale implementation.

Self-reported extracurricular activity, academic success, and quality of life in UK medical students

PubMed Central

Lumley, Sophie; Ward, Peter; Roberts, Lesley

2015-01-01

Objectives To explore the relationship between academic performance, extracurricular activity, and quality of life at medical school in the UK to aid our understanding of students’ work-life balance. Methods A cross-sectional study, using an electronic questionnaire distributed to UK final year medical students across 20 medical schools (4478 students). Participants reported the hours of self-regulated learning and extracurricular activities undertaken each year at medical school; along with their academic decile (1 = highest, 10 = lowest). Self-reported quality of life (QoL) was assessed using an established screening tool (7 = highest, 1 = lowest). Results Seven hundred responses were obtained, across 20 participating medical schools, response rate 16% (700/4478). Factors associated with higher academic achievement were: graduate entry course students (2 deciles higher, p< 0.0001), more hours academic study during term and revision periods (rho=-0.1, p< 0.01), and involvement in teaching or research. Increased hours of study was associated with lower QoL (rho = -0.13, p<0.01). Conclusions Study skills may be more important than duration spent studying, for academic achievement and QoL. Graduate-entry students attain higher decile scores despite similar self-reported duration of study. PMID:26385285

Healthy lifestyle behaviours are positively and independently associated with academic achievement: An analysis of self-reported data from a nationally representative sample of Canadian early adolescents

PubMed Central

Gleddie, Doug; Storey, Kate E.; Davison, Colleen M.; Veugelers, Paul J.

2017-01-01

Introduction The lifestyle behaviours of early adolescents, including diet, physical activity, sleep, and screen usage, are well established contributors to health. These behaviours have also been shown to be associated with academic achievement. Poor academic achievement can additionally contribute to poorer health over the lifespan. This study aims to characterize the associations between health behaviours and self-reported academic achievement. Methods Data from the 2014 Canadian Health Behaviour in School-Aged Children Study (n = 28,608, ages 11–15) were analyzed. Students provided self-report of academic achievement, diet, physical activity, sleep duration, recreational screen time usage, height, weight, and socioeconomic status. Multi-level logistic regression was used to assess the relationship of lifestyle behaviours and body weight status with academic achievement while considering sex, age, and socioeconomic status as potential confounders. Results All health behaviours exhibited independent associations with academic achievement. Frequent consumption of vegetables and fruits, breakfast and dinner with family and regular physical activity were positively associated with higher levels of academic achievement, while frequent consumption of junk food, not meeting sleep recommendations, and overweight and obesity were negatively associated with high academic achievement. Conclusions The present findings demonstrate that lifestyle behaviours are associated with academic achievement, potentially identifying these lifestyle behaviours as effective targets to improve academic achievement in early adolescents. These findings also justify investments in school-based health promotion initiatives. PMID:28753617

Higher Order, Hybrid BEM/FEM Methods Applied to Antenna Modeling

NASA Technical Reports Server (NTRS)

Fink, P. W.; Wilton, D. R.; Dobbins, J. A.

2002-01-01

In this presentation, the authors address topics relevant to higher order modeling using hybrid BEM/FEM formulations. The first of these is the limitation on convergence rates imposed by geometric modeling errors in the analysis of scattering by a dielectric sphere. The second topic is the application of an Incomplete LU Threshold (ILUT) preconditioner to solve the linear system resulting from the BEM/FEM formulation. The final tOpic is the application of the higher order BEM/FEM formulation to antenna modeling problems. The authors have previously presented work on the benefits of higher order modeling. To achieve these benefits, special attention is required in the integration of singular and near-singular terms arising in the surface integral equation. Several methods for handling these terms have been presented. It is also well known that achieving he high rates of convergence afforded by higher order bases may als'o require the employment of higher order geometry models. A number of publications have described the use of quadratic elements to model curved surfaces. The authors have shown in an EFIE formulation, applied to scattering by a PEC .sphere, that quadratic order elements may be insufficient to prevent the domination of modeling errors. In fact, on a PEC sphere with radius r = 0.58 Lambda(sub 0), a quartic order geometry representation was required to obtain a convergence benefi.t from quadratic bases when compared to the convergence rate achieved with linear bases. Initial trials indicate that, for a dielectric sphere of the same radius, - requirements on the geometry model are not as severe as for the PEC sphere. The authors will present convergence results for higher order bases as a function of the geometry model order in the hybrid BEM/FEM formulation applied to dielectric spheres. It is well known that the system matrix resulting from the hybrid BEM/FEM formulation is ill -conditioned. For many real applications, a good preconditioner is required to obtain usable convergence from an iterative solver. The authors have examined the use of an Incomplete LU Threshold (ILUT) preconditioner . to solver linear systems stemming from higher order BEM/FEM formulations in 2D scattering problems. Although the resulting preconditioner provided aD excellent approximation to the system inverse, its size in terms of non-zero entries represented only a modest improvement when compared with the fill-in associated with a sparse direct solver. Furthermore, the fill-in of the preconditioner could not be substantially reduced without the occurrence of instabilities. In addition to the results for these 2D problems, the authors will present iterative solution data from the application of the ILUT preconditioner to 3D problems.

Australian Higher Education Reforms--Unification or Diversification?

ERIC Educational Resources Information Center

Coombe, Leanne

2015-01-01

The higher education policy of the previous Australian government aimed to achieve an internationally competitive higher education sector while expanding access opportunities to all Australians. This policy agenda closely reflects global trends that focus on achieving both quality and equity objectives. In this paper, the formulation and…

A Governor's View of Higher Education.

ERIC Educational Resources Information Center

Bowen, Otis R.

A governor's perspective on higher education suggests that government needs to assure itself that the activities it funds are effective in achieving their goals, that college management practices are efficient, that postsecondary education is equally accessible to all citizens, and that excellence in higher education is achieved. Additional issues…

Revisiting the relationship between attributional style and academic performance

PubMed Central

2015-01-01

Abstract Previous research into the relationship between attributions and academic performance has produced contradictory findings that have not been resolved. The present research examines the role of specific dimensions of attributional style in predicting subsequent academic performance in a sample of pupils (N = 979) from both high‐ and low‐achieving schools. Hierarchical regression and moderation analyses indicate that internal, stable, and global, attributional styles for positive events predict higher levels of academic performance. Global attributions for negative events were related to poorer performance across all schools. Stable attributions for negative events were related to higher levels of performance in high‐achieving schools but not in low‐achieving schools. Higher levels of internality for negative events were associated with higher performance only in low achieving schools. PMID:27594711

[A new peak detection algorithm of Raman spectra].

PubMed

Jiang, Cheng-Zhi; Sun, Qiang; Liu, Ying; Liang, Jing-Qiu; An, Yan; Liu, Bing

2014-01-01

The authors proposed a new Raman peak recognition method named bi-scale correlation algorithm. The algorithm uses the combination of the correlation coefficient and the local signal-to-noise ratio under two scales to achieve Raman peak identification. We compared the performance of the proposed algorithm with that of the traditional continuous wavelet transform method through MATLAB, and then tested the algorithm with real Raman spectra. The results show that the average time for identifying a Raman spectrum is 0.51 s with the algorithm, while it is 0.71 s with the continuous wavelet transform. When the signal-to-noise ratio of Raman peak is greater than or equal to 6 (modern Raman spectrometers feature an excellent signal-to-noise ratio), the recognition accuracy with the algorithm is higher than 99%, while it is less than 84% with the continuous wavelet transform method. The mean and the standard deviations of the peak position identification error of the algorithm are both less than that of the continuous wavelet transform method. Simulation analysis and experimental verification prove that the new algorithm possesses the following advantages: no needs of human intervention, no needs of de-noising and background removal operation, higher recognition speed and higher recognition accuracy. The proposed algorithm is operable in Raman peak identification.

Instantaneous Real-Time Kinematic Decimeter-Level Positioning with BeiDou Triple-Frequency Signals over Medium Baselines.

PubMed

He, Xiyang; Zhang, Xiaohong; Tang, Long; Liu, Wanke

2015-12-22

Many applications, such as marine navigation, land vehicles location, etc., require real time precise positioning under medium or long baseline conditions. In this contribution, we develop a model of real-time kinematic decimeter-level positioning with BeiDou Navigation Satellite System (BDS) triple-frequency signals over medium distances. The ambiguities of two extra-wide-lane (EWL) combinations are fixed first, and then a wide lane (WL) combination is reformed based on the two EWL combinations for positioning. Theoretical analysis and empirical analysis is given of the ambiguity fixing rate and the positioning accuracy of the presented method. The results indicate that the ambiguity fixing rate can be up to more than 98% when using BDS medium baseline observations, which is much higher than that of dual-frequency Hatch-Melbourne-Wübbena (HMW) method. As for positioning accuracy, decimeter level accuracy can be achieved with this method, which is comparable to that of carrier-smoothed code differential positioning method. Signal interruption simulation experiment indicates that the proposed method can realize fast high-precision positioning whereas the carrier-smoothed code differential positioning method needs several hundreds of seconds for obtaining high precision results. We can conclude that a relatively high accuracy and high fixing rate can be achieved for triple-frequency WL method with single-epoch observations, displaying significant advantage comparing to traditional carrier-smoothed code differential positioning method.

Comparisons between students' learning achievements of their conventional instruction and the science, technology and social conceptual instructional design on digestion system issue of secondary students at the 10th grade level

NASA Astrophysics Data System (ADS)

Wichalek, Supattra; Chayaburakul, Kanokporn; Santiboon, Toansakul

2018-01-01

The purposes of this action research study were 1) to develop learning activities according to the instructional designing model of science, technology, and social (STS) on Digestion Issue, 2) to compare students' learning achievements between their learning activities with the conventional instructional (CIM) and conceptual instructional designing methods of science, technology, and social (STS) on digestion system of secondary students at the 10th grade level with a sample size of 35 experimental student group of their STS learning method, and 91 controlling group in two classes in the first semester in academic year 2016. Using the 4-Instructional Innovative Lesson Plans, the Students' Learning Behaviour Observing Form, the Questionnaire on Teacher Behaviour Interaction (QTBI), the Researcher's Recording Form, the Learning Activity Form, and the Parallel Learning Achievement Test (LAT) were assessed. The results of this research have found that; the Index of Item Objective Congruence (IOC) value ranged from 0.67 to 1.00; the difficulty values were 0.47 and 0.79 for the CIM and STS methods, respectively, the discriminative validity for the LAT was ranged from 0.20 to 0.75. The reliability of the QTBI was 0.79. Students' responses of their learning achievements with the average means scores indicted of the normalized gain values of 0.79 for the STS group, and 0.50 and 0.36 for the CIM groups, respectively. Students' learning achievements of their post-test indicated that of a higher than pre-test, the pre-test and post-test assessments were also differentiated evidence at the 0.05 levels for the STS and CIM groups, significantly. The 22-students' learning outcomes from the STS group evidences at a high level, only of the 9-students' responses in a moderate level were developed of their learning achievements, responsibility.

Development of a three-dimensional high-order strand-grids approach

NASA Astrophysics Data System (ADS)

Tong, Oisin

Development of a novel high-order flux correction method on strand grids is presented. The method uses a combination of flux correction in the unstructured plane and summation-by-parts operators in the strand direction to achieve high-fidelity solutions. Low-order truncation errors are cancelled with accurate flux and solution gradients in the flux correction method, thereby achieving a formal order of accuracy of 3, although higher orders are often obtained, especially for highly viscous flows. In this work, the scheme is extended to high-Reynolds number computations in both two and three dimensions. Turbulence closure is achieved with a robust version of the Spalart-Allmaras turbulence model that accommodates negative values of the turbulence working variable, and the Menter SST turbulence model, which blends the k-epsilon and k-o turbulence models for better accuracy. A major advantage of this high-order formulation is the ability to implement traditional finite volume-like limiters to cleanly capture shocked and discontinuous flows. In this work, this approach is explored via a symmetric limited positive (SLIP) limiter. Extensive verification and validation is conducted in two and three dimensions to determine the accuracy and fidelity of the scheme for a number of different cases. Verification studies show that the scheme achieves better than third order accuracy for low and high-Reynolds number flows. Cost studies show that in three-dimensions, the third-order flux correction scheme requires only 30% more walltime than a traditional second-order scheme on strand grids to achieve the same level of convergence. In order to overcome meshing issues at sharp corners and other small-scale features, a unique approach to traditional geometry, coined "asymptotic geometry," is explored. Asymptotic geometry is achieved by filtering out small-scale features in a level set domain through min/max flow. This approach is combined with a curvature based strand shortening strategy in order to qualitatively improve strand grid mesh quality.

Effect of cross-link density on carbon dioxide separation in polydimethylsiloxane-norbornene membranes

DOE PAGES

Hong, Tao; Niu, Zhenbin; Hu, Xunxiang; ...

2015-10-20

The development of high performance materials for CO 2 separation and capture will significantly contribute to a solution for climate change. In this work, (bicycloheptenyl) ethyl terminated polydimethylsiloxane (PDMSPNB) membranes with varied cross-link densities were synthesized via ring-opening metathesis polymerization. The developed polymer membranes show higher permeability and better selectivity than those of conventional cross-linked PDMS membrane. The achieved performance (CO 2 permeability ~ 6800 Barrer and CO 2/N 2 selectivity ~ 14) is very promising for practical applications. The key to achieving this high performance is the use of an in-situ cross-linking method of the difunctional PDMS macromonomers, whichmore » provides lightly cross-linked membranes. By combining positron annihilation lifetime spectroscopy, broadband dielectric spectroscopy and gas solubility measurements, we have elucidated the key parameters necessary for achieving their excellent performance.« less

Surface Roughness Optimization Using Taguchi Method of High Speed End Milling For Hardened Steel D2

NASA Astrophysics Data System (ADS)

Hazza Faizi Al-Hazza, Muataz; Ibrahim, Nur Asmawiyah bt; Adesta, Erry T. Y.; Khan, Ahsan Ali; Abdullah Sidek, Atiah Bt.

2017-03-01

The main challenge for any manufacturer is to achieve higher quality of their final products with maintains minimum machining time. In this research final surface roughness analysed and optimized with maximum 0.3 mm flank wear length. The experiment was investigated the effect of cutting speed, feed rate and depth of cut on the final surface roughness using D2 as a work piece hardened to 52-56 HRC, and coated carbide as cutting tool with higher cutting speed 120-240 mm/min. The experiment has been conducted using L9 design of Taguchi collection. The results have been analysed using JMP software.

Intellectual Interest Mediates Gene-by-SES Interaction on Adolescent Academic Achievement

PubMed Central

Tucker-Drob, Elliot M.; Harden, K. Paige

2011-01-01

Recent studies have demonstrated that genetic influences on cognitive ability and academic achievement are larger for children raised in higher socioeconomic status (SES) homes. However, little work has been done to document the psychosocial processes that underlie this gene-by-environment interaction. One process may involve the conversion of intellectual interest into academic achievement. Analyses of data from 777 pairs of 17-year-old twins indicated that gene-by-SES effects on achievement scores can be accounted for by stronger influences of genes for intellectual interest on achievement at higher levels of SES. These findings are consistent with the hypothesis that higher SES affords greater opportunity for children to seek out and benefit from learning experiences that are congruent with their genetically influenced intellectual interests. PMID:22288554

Temporal resolution improvement using PICCS in MDCT cardiac imaging

PubMed Central

Chen, Guang-Hong; Tang, Jie; Hsieh, Jiang

2009-01-01

The current paradigm for temporal resolution improvement is to add more source-detector units and∕or increase the gantry rotation speed. The purpose of this article is to present an innovative alternative method to potentially improve temporal resolution by approximately a factor of 2 for all MDCT scanners without requiring hardware modification. The central enabling technology is a most recently developed image reconstruction method: Prior image constrained compressed sensing (PICCS). Using the method, cardiac CT images can be accurately reconstructed using the projection data acquired in an angular range of about 120°, which is roughly 50% of the standard short-scan angular range (∼240° for an MDCT scanner). As a result, the temporal resolution of MDCT cardiac imaging can be universally improved by approximately a factor of 2. In order to validate the proposed method, two in vivo animal experiments were conducted using a state-of-the-art 64-slice CT scanner (GE Healthcare, Waukesha, WI) at different gantry rotation times and different heart rates. One animal was scanned at heart rate of 83 beats per minute (bpm) using 400 ms gantry rotation time and the second animal was scanned at 94 bpm using 350 ms gantry rotation time, respectively. Cardiac coronary CT imaging can be successfully performed at high heart rates using a single-source MDCT scanner and projection data from a single heart beat with gantry rotation times of 400 and 350 ms. Using the proposed PICCS method, the temporal resolution of cardiac CT imaging can be effectively improved by approximately a factor of 2 without modifying any scanner hardware. This potentially provides a new method for single-source MDCT scanners to achieve reliable coronary CT imaging for patients at higher heart rates than the current heart rate limit of 70 bpm without using the well-known multisegment FBP reconstruction algorithm. This method also enables dual-source MDCT scanner to achieve higher temporal resolution without further hardware modifications. PMID:19610302

Temporal resolution improvement using PICCS in MDCT cardiac imaging.

PubMed

Chen, Guang-Hong; Tang, Jie; Hsieh, Jiang

2009-06-01

The current paradigm for temporal resolution improvement is to add more source-detector units and/or increase the gantry rotation speed. The purpose of this article is to present an innovative alternative method to potentially improve temporal resolution by approximately a factor of 2 for all MDCT scanners without requiring hardware modification. The central enabling technology is a most recently developed image reconstruction method: Prior image constrained compressed sensing (PICCS). Using the method, cardiac CT images can be accurately reconstructed using the projection data acquired in an angular range of about 120 degrees, which is roughly 50% of the standard short-scan angular range (approximately 240 degrees for an MDCT scanner). As a result, the temporal resolution of MDCT cardiac imaging can be universally improved by approximately a factor of 2. In order to validate the proposed method, two in vivo animal experiments were conducted using a state-of-the-art 64-slice CT scanner (GE Healthcare, Waukesha, WI) at different gantry rotation times and different heart rates. One animal was scanned at heart rate of 83 beats per minute (bpm) using 400 ms gantry rotation time and the second animal was scanned at 94 bpm using 350 ms gantry rotation time, respectively. Cardiac coronary CT imaging can be successfully performed at high heart rates using a single-source MDCT scanner and projection data from a single heart beat with gantry rotation times of 400 and 350 ms. Using the proposed PICCS method, the temporal resolution of cardiac CT imaging can be effectively improved by approximately a factor of 2 without modifying any scanner hardware. This potentially provides a new method for single-source MDCT scanners to achieve reliable coronary CT imaging for patients at higher heart rates than the current heart rate limit of 70 bpm without using the well-known multisegment FBP reconstruction algorithm. This method also enables dual-source MDCT scanner to achieve higher temporal resolution without further hardware modifications.

Exploiting vibrational resonance in weak-signal detection

NASA Astrophysics Data System (ADS)

Ren, Yuhao; Pan, Yan; Duan, Fabing; Chapeau-Blondeau, François; Abbott, Derek

2017-08-01

In this paper, we investigate the first exploitation of the vibrational resonance (VR) effect to detect weak signals in the presence of strong background noise. By injecting a series of sinusoidal interference signals of the same amplitude but with different frequencies into a generalized correlation detector, we show that the detection probability can be maximized at an appropriate interference amplitude. Based on a dual-Dirac probability density model, we compare the VR method with the stochastic resonance approach via adding dichotomous noise. The compared results indicate that the VR method can achieve a higher detection probability for a wider variety of noise distributions.

Digital holographic microscope with low-frequency attenuation filter for position measurement of a nanoparticle.

PubMed

Pham, Quang Duc; Kusumi, Yuichi; Hasegawa, Satoshi; Hayasaki, Yoshio

2012-10-01

We propose a new method for three-dimensional (3D) position measurement of nanoparticles using an in-line digital holographic microscope. The method improves the signal-to-noise ratio of the amplitude of the interference fringes to achieve higher accuracy in the position measurement by increasing weak scattered light from a nanoparticle relative to the reference light by using a low spatial frequency attenuation filter. We demonstrated the improvements of signal-to-noise ratio of the optical system and contrast of the interference fringes, allowing the 3D positions of nanoparticles to be determined more precisely.

Exploiting vibrational resonance in weak-signal detection.

PubMed

Ren, Yuhao; Pan, Yan; Duan, Fabing; Chapeau-Blondeau, François; Abbott, Derek

2017-08-01

In this paper, we investigate the first exploitation of the vibrational resonance (VR) effect to detect weak signals in the presence of strong background noise. By injecting a series of sinusoidal interference signals of the same amplitude but with different frequencies into a generalized correlation detector, we show that the detection probability can be maximized at an appropriate interference amplitude. Based on a dual-Dirac probability density model, we compare the VR method with the stochastic resonance approach via adding dichotomous noise. The compared results indicate that the VR method can achieve a higher detection probability for a wider variety of noise distributions.

Pentadiagonal alternating-direction-implicit finite-difference time-domain method for two-dimensional Schrödinger equation

NASA Astrophysics Data System (ADS)

Tay, Wei Choon; Tan, Eng Leong

2014-07-01

In this paper, we have proposed a pentadiagonal alternating-direction-implicit (Penta-ADI) finite-difference time-domain (FDTD) method for the two-dimensional Schrödinger equation. Through the separation of complex wave function into real and imaginary parts, a pentadiagonal system of equations for the ADI method is obtained, which results in our Penta-ADI method. The Penta-ADI method is further simplified into pentadiagonal fundamental ADI (Penta-FADI) method, which has matrix-operator-free right-hand-sides (RHS), leading to the simplest and most concise update equations. As the Penta-FADI method involves five stencils in the left-hand-sides (LHS) of the pentadiagonal update equations, special treatments that are required for the implementation of the Dirichlet's boundary conditions will be discussed. Using the Penta-FADI method, a significantly higher efficiency gain can be achieved over the conventional Tri-ADI method, which involves a tridiagonal system of equations.

Undirected learning styles and academic risk: Analysis of the impact of stress, strain and coping.

PubMed

Kimatian, Stephen; Lloyd, Sara; Berger, Jeffrey; Steiner, Lorraine; McKay, Robert; Schwengal, Deborah

2017-01-01

Learning style inventories used in conjunction with a measure of academic achievement consistently show an association of meaning directed learning patterns with academic success, but have failed to show a clear association of undirected learning styles with academic failure. Using survey methods with anesthesia residents, this study questioned whether additional assessment of factors related to stress, strain, and coping help to better define the association between undirected learning styles and academic risk. Pearson chi squared tests. 296 subjects were enrolled from eight institutions with 142 (48%) completing the study. American Board of Anesthesiologists In Training Examinations (ITE) percentiles (ITE%) were used as a measure of academic achievement. The Vermunt Inventory of Learning Styles (ILS) was used to identify four learning patterns and 20 strategies, and the Osipow Stress Inventory-Revised (OSI-R) was used as a measure of six scales of occupational stress, four of personal strain, and four coping resources. Two learning patterns had significant relationship with ITE scores. As seen in previous studies, Meaning Directed Learning was beneficial for academic achievement while Undirected Learning was the least beneficial. Higher scores on Meaning Directed Learning correlated positively with higher ITE scores while higher Undirected and lower Meaning Directed patterns related negatively to ITE%. OSI-R measures of stress, strain and coping indicated that residents with Undirected learning patterns had higher scores on three scales related to stress, and 4 related to strain, while displaying lower scores on two scales related to coping. Residents with higher Meaning Directed patterns scored lower on two scales of stress and two scales of strain, with higher scores on two scales for coping resources. Low Meaning Directed and high Undirected learning patterns correlated with lower ITE percentiles, higher scores for stress and strain, and lower coping resources. This association suggests that successful remediation of at-risk residents must address stress, strain and coping if long term academic improvement is expected. Further research to identify the value of stress, strain, and coping screening and education is warranted.

Recovery Efficiency and Limit of Detection of Aerosolized Bacillus anthracis Sterne from Environmental Surface Samples ▿

PubMed Central

Estill, Cheryl Fairfield; Baron, Paul A.; Beard, Jeremy K.; Hein, Misty J.; Larsen, Lloyd D.; Rose, Laura; Schaefer, Frank W.; Noble-Wang, Judith; Hodges, Lisa; Lindquist, H. D. Alan; Deye, Gregory J.; Arduino, Matthew J.

2009-01-01

After the 2001 anthrax incidents, surface sampling techniques for biological agents were found to be inadequately validated, especially at low surface loadings. We aerosolized Bacillus anthracis Sterne spores within a chamber to achieve very low surface loading (ca. 3, 30, and 200 CFU per 100 cm2). Steel and carpet coupons seeded in the chamber were sampled with swab (103 cm2) or wipe or vacuum (929 cm2) surface sampling methods and analyzed at three laboratories. Agar settle plates (60 cm2) were the reference for determining recovery efficiency (RE). The minimum estimated surface concentrations to achieve a 95% response rate based on probit regression were 190, 15, and 44 CFU/100 cm2 for sampling steel surfaces and 40, 9.2, and 28 CFU/100 cm2 for sampling carpet surfaces with swab, wipe, and vacuum methods, respectively; however, these results should be cautiously interpreted because of high observed variability. Mean REs at the highest surface loading were 5.0%, 18%, and 3.7% on steel and 12%, 23%, and 4.7% on carpet for the swab, wipe, and vacuum methods, respectively. Precision (coefficient of variation) was poor at the lower surface concentrations but improved with increasing surface concentration. The best precision was obtained with wipe samples on carpet, achieving 38% at the highest surface concentration. The wipe sampling method detected B. anthracis at lower estimated surface concentrations and had higher RE and better precision than the other methods. These results may guide investigators to more meaningfully conduct environmental sampling, quantify contamination levels, and conduct risk assessment for humans. PMID:19429546

Force estimation from OCT volumes using 3D CNNs.

PubMed

Gessert, Nils; Beringhoff, Jens; Otte, Christoph; Schlaefer, Alexander

2018-07-01

Estimating the interaction forces of instruments and tissue is of interest, particularly to provide haptic feedback during robot-assisted minimally invasive interventions. Different approaches based on external and integrated force sensors have been proposed. These are hampered by friction, sensor size, and sterilizability. We investigate a novel approach to estimate the force vector directly from optical coherence tomography image volumes. We introduce a novel Siamese 3D CNN architecture. The network takes an undeformed reference volume and a deformed sample volume as an input and outputs the three components of the force vector. We employ a deep residual architecture with bottlenecks for increased efficiency. We compare the Siamese approach to methods using difference volumes and two-dimensional projections. Data were generated using a robotic setup to obtain ground-truth force vectors for silicon tissue phantoms as well as porcine tissue. Our method achieves a mean average error of [Formula: see text] when estimating the force vector. Our novel Siamese 3D CNN architecture outperforms single-path methods that achieve a mean average error of [Formula: see text]. Moreover, the use of volume data leads to significantly higher performance compared to processing only surface information which achieves a mean average error of [Formula: see text]. Based on the tissue dataset, our methods shows good generalization in between different subjects. We propose a novel image-based force estimation method using optical coherence tomography. We illustrate that capturing the deformation of subsurface structures substantially improves force estimation. Our approach can provide accurate force estimates in surgical setups when using intraoperative optical coherence tomography.

Recovery efficiency and limit of detection of aerosolized Bacillus anthracis Sterne from environmental surface samples.

PubMed

Estill, Cheryl Fairfield; Baron, Paul A; Beard, Jeremy K; Hein, Misty J; Larsen, Lloyd D; Rose, Laura; Schaefer, Frank W; Noble-Wang, Judith; Hodges, Lisa; Lindquist, H D Alan; Deye, Gregory J; Arduino, Matthew J

2009-07-01

After the 2001 anthrax incidents, surface sampling techniques for biological agents were found to be inadequately validated, especially at low surface loadings. We aerosolized Bacillus anthracis Sterne spores within a chamber to achieve very low surface loading (ca. 3, 30, and 200 CFU per 100 cm(2)). Steel and carpet coupons seeded in the chamber were sampled with swab (103 cm(2)) or wipe or vacuum (929 cm(2)) surface sampling methods and analyzed at three laboratories. Agar settle plates (60 cm(2)) were the reference for determining recovery efficiency (RE). The minimum estimated surface concentrations to achieve a 95% response rate based on probit regression were 190, 15, and 44 CFU/100 cm(2) for sampling steel surfaces and 40, 9.2, and 28 CFU/100 cm(2) for sampling carpet surfaces with swab, wipe, and vacuum methods, respectively; however, these results should be cautiously interpreted because of high observed variability. Mean REs at the highest surface loading were 5.0%, 18%, and 3.7% on steel and 12%, 23%, and 4.7% on carpet for the swab, wipe, and vacuum methods, respectively. Precision (coefficient of variation) was poor at the lower surface concentrations but improved with increasing surface concentration. The best precision was obtained with wipe samples on carpet, achieving 38% at the highest surface concentration. The wipe sampling method detected B. anthracis at lower estimated surface concentrations and had higher RE and better precision than the other methods. These results may guide investigators to more meaningfully conduct environmental sampling, quantify contamination levels, and conduct risk assessment for humans.

Ratioing methods for in-flight response calibration of space-based spectro-radiometers, operating in the solar spectral region

NASA Astrophysics Data System (ADS)

Lobb, Dan

2017-11-01

One of the most significant problems for space-based spectro-radiometer systems, observing Earth from space in the solar spectral band (UV through short-wave IR), is in achievement of the required absolute radiometric accuracy. Classical methods, for example using one or more sun-illuminated diffusers as reflectance standards, do not generally provide methods for monitoring degradation of the in-flight reference after pre-flight characterisation. Ratioing methods have been proposed that provide monitoring of degradation of solar attenuators in flight, thus in principle allowing much higher confidence in absolute response calibration. Two example methods are described. It is shown that systems can be designed for relatively low size and without significant additions to the complexity of flight hardware.

Neuroanatomical correlates of the income-achievement gap.

PubMed

Mackey, Allyson P; Finn, Amy S; Leonard, Julia A; Jacoby-Senghor, Drew S; West, Martin R; Gabrieli, Christopher F O; Gabrieli, John D E

2015-06-01

In the United States, the difference in academic achievement between higher- and lower-income students (i.e., the income-achievement gap) is substantial and growing. In the research reported here, we investigated neuroanatomical correlates of this gap in adolescents (N = 58) in whom academic achievement was measured by statewide standardized testing. Cortical gray-matter volume was significantly greater in students from higher-income backgrounds (n = 35) than in students from lower-income backgrounds (n = 23), but cortical white-matter volume and total cortical surface area did not differ significantly between groups. Cortical thickness in all lobes of the brain was greater in students from higher-income than lower-income backgrounds. Greater cortical thickness, particularly in temporal and occipital lobes, was associated with better test performance. These results represent the first evidence that cortical thickness in higher- and lower-income students differs across broad swaths of the brain and that cortical thickness is related to scores on academic-achievement tests. © The Author(s) 2015.

A systematic methodology for creep master curve construction using the stepped isostress method (SSM): a numerical assessment

NASA Astrophysics Data System (ADS)

Miranda Guedes, Rui

2018-02-01

Long-term creep of viscoelastic materials is experimentally inferred through accelerating techniques based on the time-temperature superposition principle (TTSP) or on the time-stress superposition principle (TSSP). According to these principles, a given property measured for short times at a higher temperature or higher stress level remains the same as that obtained for longer times at a lower temperature or lower stress level, except that the curves are shifted parallel to the horizontal axis, matching a master curve. These procedures enable the construction of creep master curves with short-term experimental tests. The Stepped Isostress Method (SSM) is an evolution of the classical TSSP method. Higher reduction of the required number of test specimens to obtain the master curve is achieved by the SSM technique, since only one specimen is necessary. The classical approach, using creep tests, demands at least one specimen per each stress level to produce a set of creep curves upon which TSSP is applied to obtain the master curve. This work proposes an analytical method to process the SSM raw data. The method is validated using numerical simulations to reproduce the SSM tests based on two different viscoelastic models. One model represents the viscoelastic behavior of a graphite/epoxy laminate and the other represents an adhesive based on epoxy resin.

The Impact of Learning Styles on Student Achievement in a Web-Based versus an Equivalent Face-to-Face Course

ERIC Educational Resources Information Center

Zacharis, Nick Z.

2010-01-01

This study investigated the relationship between students' learning styles and their achievement in two different learning environments: online instruction and traditional instruction. The results indicated that a) students in the traditional learning group had higher, but not statistically significant higher, levels of achievement than students…

Validity of Assessment and Recognition of Non-Formal and Informal Learning Achievements in Higher Education

ERIC Educational Resources Information Center

Kaminskiene, Lina; Stasiunaitiene, Egle

2013-01-01

The article identifies the validity of assessment of non-formal and informal learning achievements (NILA) as one of the key factors for encouraging further development of the process of assessing and recognising non-formal and informal learning achievements in higher education. The authors analyse why the recognition of non-formal and informal…

Building and Using a Social Network: Nurture for Low-Income Chinese American Adolescents' Learning

ERIC Educational Resources Information Center

Li, Jin; Holloway, Susan D.; Bempechat, Janine; Loh, Elaine

2008-01-01

Little research has examined how low-income Asian American children are supported to achieve well in school. The authors used the notion of social capital to study higher versus lower achieving Chinese adolescents from low-income backgrounds. They found that families of higher-achieving adolescents built and used more effectively three kinds of…

An adaptive confidence limit for periodic non-steady conditions fault detection

NASA Astrophysics Data System (ADS)

Wang, Tianzhen; Wu, Hao; Ni, Mengqi; Zhang, Milu; Dong, Jingjing; Benbouzid, Mohamed El Hachemi; Hu, Xiong

2016-05-01

System monitoring has become a major concern in batch process due to the fact that failure rate in non-steady conditions is much higher than in steady ones. A series of approaches based on PCA have already solved problems such as data dimensionality reduction, multivariable decorrelation, and processing non-changing signal. However, if the data follows non-Gaussian distribution or the variables contain some signal changes, the above approaches are not applicable. To deal with these concerns and to enhance performance in multiperiod data processing, this paper proposes a fault detection method using adaptive confidence limit (ACL) in periodic non-steady conditions. The proposed ACL method achieves four main enhancements: Longitudinal-Standardization could convert non-Gaussian sampling data to Gaussian ones; the multiperiod PCA algorithm could reduce dimensionality, remove correlation, and improve the monitoring accuracy; the adaptive confidence limit could detect faults under non-steady conditions; the fault sections determination procedure could select the appropriate parameter of the adaptive confidence limit. The achieved result analysis clearly shows that the proposed ACL method is superior to other fault detection approaches under periodic non-steady conditions.

Low-Dimensional Feature Representation for Instrument Identification

NASA Astrophysics Data System (ADS)

Ihara, Mizuki; Maeda, Shin-Ichi; Ikeda, Kazushi; Ishii, Shin

For monophonic music instrument identification, various feature extraction and selection methods have been proposed. One of the issues toward instrument identification is that the same spectrum is not always observed even in the same instrument due to the difference of the recording condition. Therefore, it is important to find non-redundant instrument-specific features that maintain information essential for high-quality instrument identification to apply them to various instrumental music analyses. For such a dimensionality reduction method, the authors propose the utilization of linear projection methods: local Fisher discriminant analysis (LFDA) and LFDA combined with principal component analysis (PCA). After experimentally clarifying that raw power spectra are actually good for instrument classification, the authors reduced the feature dimensionality by LFDA or by PCA followed by LFDA (PCA-LFDA). The reduced features achieved reasonably high identification performance that was comparable or higher than those by the power spectra and those achieved by other existing studies. These results demonstrated that our LFDA and PCA-LFDA can successfully extract low-dimensional instrument features that maintain the characteristic information of the instruments.

Probe-level linear model fitting and mixture modeling results in high accuracy detection of differential gene expression.

PubMed

Lemieux, Sébastien

2006-08-25

The identification of differentially expressed genes (DEGs) from Affymetrix GeneChips arrays is currently done by first computing expression levels from the low-level probe intensities, then deriving significance by comparing these expression levels between conditions. The proposed PL-LM (Probe-Level Linear Model) method implements a linear model applied on the probe-level data to directly estimate the treatment effect. A finite mixture of Gaussian components is then used to identify DEGs using the coefficients estimated by the linear model. This approach can readily be applied to experimental design with or without replication. On a wholly defined dataset, the PL-LM method was able to identify 75% of the differentially expressed genes within 10% of false positives. This accuracy was achieved both using the three replicates per conditions available in the dataset and using only one replicate per condition. The method achieves, on this dataset, a higher accuracy than the best set of tools identified by the authors of the dataset, and does so using only one replicate per condition.

Shifted Transversal Design smart-pooling for high coverage interactome mapping

PubMed Central

Xin, Xiaofeng; Rual, Jean-François; Hirozane-Kishikawa, Tomoko; Hill, David E.; Vidal, Marc; Boone, Charles; Thierry-Mieg, Nicolas

2009-01-01

“Smart-pooling,” in which test reagents are multiplexed in a highly redundant manner, is a promising strategy for achieving high efficiency, sensitivity, and specificity in systems-level projects. However, previous applications relied on low redundancy designs that do not leverage the full potential of smart-pooling, and more powerful theoretical constructions, such as the Shifted Transversal Design (STD), lack experimental validation. Here we evaluate STD smart-pooling in yeast two-hybrid (Y2H) interactome mapping. We employed two STD designs and two established methods to perform ORFeome-wide Y2H screens with 12 baits. We found that STD pooling achieves similar levels of sensitivity and specificity as one-on-one array-based Y2H, while the costs and workloads are divided by three. The screening-sequencing approach is the most cost- and labor-efficient, yet STD identifies about twofold more interactions. Screening-sequencing remains an appropriate method for quickly producing low-coverage interactomes, while STD pooling appears as the method of choice for obtaining maps with higher coverage. PMID:19447967

System-level protection and hardware Trojan detection using weighted voting.

PubMed

Amin, Hany A M; Alkabani, Yousra; Selim, Gamal M I

2014-07-01

The problem of hardware Trojans is becoming more serious especially with the widespread of fabless design houses and design reuse. Hardware Trojans can be embedded on chip during manufacturing or in third party intellectual property cores (IPs) during the design process. Recent research is performed to detect Trojans embedded at manufacturing time by comparing the suspected chip with a golden chip that is fully trusted. However, Trojan detection in third party IP cores is more challenging than other logic modules especially that there is no golden chip. This paper proposes a new methodology to detect/prevent hardware Trojans in third party IP cores. The method works by gradually building trust in suspected IP cores by comparing the outputs of different untrusted implementations of the same IP core. Simulation results show that our method achieves higher probability of Trojan detection over a naive implementation of simple voting on the output of different IP cores. In addition, experimental results show that the proposed method requires less hardware overhead when compared with a simple voting technique achieving the same degree of security.

Breakfast, midday meals and academic achievement in rural primary schools in Uganda: implications for education and school health policy

PubMed Central

Acham, Hedwig; Kikafunda, Joyce K.; Malde, Marian K.; Oldewage-Theron, Wilna H.; Egal, AbdulKadir A.

2012-01-01

Background Underachievement in schools is a global problem and is especially prevalent in developing countries. Indicators of educational performance show that Uganda has done remarkably well on education access-related targets since the introduction of universal primary education in 1997. However, educational outcomes remain disappointing. The absence of school feeding schemes, one of the leading causes of scholastic underachievement, has not been given attention by the Ugandan authorities. Instead, as a national policy, parents are expected to provide meals even though many, especially in the rural areas, cannot afford to provide even the minimal daily bowl of maize porridge. Objective To assess and demonstrate the effect of breakfast and midday meal consumption on academic achievement of schoolchildren. Design, Materials and Methods We assessed household characteristics, feeding patterns and academic achievement of 645 schoolchildren (aged 9–15 years) in Kumi district, eastern Uganda, in 2006–2007, using a modified cluster sampling design which involved only grade 1 schools (34 in total) and pupils of grade four. Household questionnaires and school records were used to collect information on socio-demographic factors, feeding patterns and school attendance. Academic achievement was assessed using unstandardized techniques, specifically designed for this study. Results Underachievement (the proportion below a score of 120.0 points) was high (68.4%); in addition, significantly higher achievement and better feeding patterns were observed among children from the less poor households (p<0.05). Achievement was significantly associated with consumption of breakfast and a midday meal, particularly for boys (p<0.05), and a greater likelihood of scoring well was observed for better nourished children (all OR values>1.0). Conclusion We observed that underachievement was relatively high; inadequate patterns of meal consumption, particularly for the most poor, significantly higher scores among children from ‘less poor’ households and a significant association between academic achievement and breakfast and midday meal consumption. PMID:22347147

Three dimensional range geometry and texture data compression with space-filling curves.

PubMed

Chen, Xia; Zhang, Song

2017-10-16

This paper presents a novel method to effectively store three-dimensional (3D) data and 2D texture data into a regular 24-bit image. The proposed method uses the Hilbert space-filling curve to map the normalized unwrapped phase map to two 8-bit color channels, and saves the third color channel for 2D texture storage. By further leveraging existing 2D image and video compression techniques, the proposed method can achieve high compression ratios while effectively preserving data quality. Since the encoding and decoding processes can be applied to most of the current 2D media platforms, this proposed compression method can make 3D data storage and transmission available for many electrical devices without requiring special hardware changes. Experiments demonstrate that if a lossless 2D image/video format is used, both original 3D geometry and 2D color texture can be accurately recovered; if lossy image/video compression is used, only black-and-white or grayscale texture can be properly recovered, but much higher compression ratios (e.g., 1543:1 against the ASCII OBJ format) are achieved with slight loss of 3D geometry quality.

Influence of Three Different Methods of Teaching Physics on the Gain in Students' Development of Reasoning

NASA Astrophysics Data System (ADS)

Marušić, Mirko; Sliško, Josip

2012-01-01

The Lawson Classroom Test of Scientific Reasoning (LCTSR) was used to gauge the relative effectiveness of three different methods of pedagogy, Reading, Presenting, and Questioning (RPQ), Experimenting and Discussion (ED), and Traditional Methods (TM), on increasing students' level of scientific thinking. The data of a one-semester-long senior high-school project indicate that, for the LCTSR: (a) the RPQ group (n = 91) achieved effect-sizes d = 0.30 and (b) the ED group (n  =  85) attained effect-sizes d = 0.64. These methods have shown that the Piagetian and Vygotskian visions on learning and teaching can go hand in hand and as such achieve respectable results. To do so, it is important to challenge the students and thus encourage the shift towards higher levels of reasoning. This aim is facilitated through class management which recognizes the importance of collaborative learning. Carrying out Vygotsky's original intention to use teaching to promote cognitive development as well as subject concepts, this research has shown that it is better to have students experience cognitive conflict from directly observed experiments than by reflecting on reported experience from popularization papers or writings found on the internet.

Optimum SNR data compression in hardware using an Eigencoil array.

PubMed

King, Scott B; Varosi, Steve M; Duensing, G Randy

2010-05-01

With the number of receivers available on clinical MRI systems now ranging from 8 to 32 channels, data compression methods are being explored to lessen the demands on the computer for data handling and processing. Although software-based methods of compression after reception lessen computational requirements, a hardware-based method before the receiver also reduces the number of receive channels required. An eight-channel Eigencoil array is constructed by placing a hardware radiofrequency signal combiner inline after preamplification, before the receiver system. The Eigencoil array produces signal-to-noise ratio (SNR) of an optimal reconstruction using a standard sum-of-squares reconstruction, with peripheral SNR gains of 30% over the standard array. The concept of "receiver channel reduction" or MRI data compression is demonstrated, with optimal SNR using only four channels, and with a three-channel Eigencoil, superior sum-of-squares SNR was achieved over the standard eight-channel array. A three-channel Eigencoil portion of a product neurovascular array confirms in vivo SNR performance and demonstrates parallel MRI up to R = 3. This SNR-preserving data compression method advantageously allows users of MRI systems with fewer receiver channels to achieve the SNR of higher-channel MRI systems. (c) 2010 Wiley-Liss, Inc.

Measurement of Density, Sound Velocity, Surface Tension, and Viscosity of Freely Suspended Supercooled Liquids

NASA Technical Reports Server (NTRS)

Trinh, E. H.

1995-01-01

Non-contact methods have been implemented in conjunction with levitation techniques to carry out the measurement of the macroscopic properties of liquids significantly cooled below their nominal melting point. Free suspension of the sample and remote methods allow the deep excursion into the metastable liquid state and the determination of its thermophysical properties. We used this approach to investigate common substances such as water, o-terphenyl, succinonitrile, as well as higher temperature melts such as molten indium, aluminum and other metals. Although these techniques have thus far involved ultrasonic, electromagnetic, and more recently electrostatic levitation, we restrict our attention to ultrasonic methods in this paper. The resulting magnitude of maximum thermal supercooling achieved have ranged between 10 and 15% of the absolute temperature of the melting point for the materials mentioned above. The physical properties measurement methods have been mostly novel approaches, and the typical accuracy achieved have not yet matched their standard equivalent techniques involving contained samples and invasive probing. They are currently being refined, however, as the levitation techniques become more widespread, and as we gain a better understanding of the physics of levitated liquid samples.

Measurement of density, sound velocity, surface tension, and viscosity of freely suspended supercooled liquids

NASA Astrophysics Data System (ADS)

Trinh, E. H.; Ohsaka, K.

1995-03-01

Noncontact methods have been implemented in conjunction with levitation techniques to carry out the measurement of the macroscopic properties of liquids significantly cooled below their nominal melting point. Free suspension of the sample and remote methods allow the deep excursion into the metastable liquid state and the determination of its thermophysical properties. We used this approach to investigate common substances such as water, v-terphenyl. succinonitrile, as well as higher temperature melts such as molten indium, aluminum, and other metals. Although these techniques have thus far involved ultrasonic, eletromagnetic, and more recently electrostatic levitation, we restrict our attention to ultrasonic methods in this paper. The resulting magnitude of maximum thermal supercooling achieved has ranged between 10% and 15% of the absolute temperature of the melting point for the materials mentioned above. The methods for measuring the physical properties have been mostly novel approaches, and the typical accuracy achieved has not yet matched the standard equivalent techniques involving contained samples and invasive probing. They are currently being refined, however, as the levitation techniques become more widespread and as we gain a better understanding of the physics of levitated liquid samples.

Effects of the Higher Order Thinking Skills Program on At-Risk Young Adolescents' Self-Concept, Reading Achievement, and Thinking Skills.

ERIC Educational Resources Information Center

Eisenman, Gordon; Payne, Beverly D.

1997-01-01

Contrasted effects of Higher Order Thinking Skills (HOTS) program to those of Chapter 1 programs on fourth and fifth graders' reading achievement, self-concept, and higher-order thinking skills. Found that HOTS is more effective in raising self-concept and some higher-order thinking skills in fifth grade and after two years of treatment, with…

Is Equal Access to Higher Education in South Asia and Sub-Saharan Africa Achievable by 2030?

ERIC Educational Resources Information Center

Ilie, Sonia; Rose, Pauline

2016-01-01

Higher education is back in the spotlight, with post-2015 sustainable development goals emphasising equality of access. In this paper, we highlight the long distance still to travel to achieve the goal of equal access to higher education for all, with a focus on poorer countries which tend to have lower levels of enrolment in higher education.…

Milestone achievement in emerging adulthood in spina bifida: a longitudinal investigation of parental expectations

PubMed Central

Holbein, Christina E; Zebracki, Kathy; Bechtel, Colleen F; Papadakis, Jaclyn Lennon; Bruno, Elizabeth Franks; Holmbeck, Grayson N

2016-01-01

Aim To assess changes over time in parents' expectations of adult milestone achievement (college attendance, full-time job attainment, independent living, marriage, parenthood) for young people with spina bifida, to examine how expectancies relate to actual milestone achievement, and to compare milestone achievement in emerging adults with spina bifida with that of peers with typical development. Method Sixty-eight families of children with spina bifida (mean=8.34y, 37 male, 31 female) and 68 families of children with typical development (mean=8.49y, 37 male, 31 female) participated at Time 1. At all subsequent timepoints, parents of young people with spina bifida were asked to rate their expectations of emerging adulthood milestone achievement. At Time 7, when participants were 22 to 23 years old, milestone achievement was assessed. Results Parents of young people with spina bifida lowered their expectations over time for most milestones; parents of children with higher cognitive ability reported decreases of lower magnitude. Parent expectancies were optimistic and unrelated to actual milestone achievement. Emerging adults with spina bifida were less likely than individuals with typical development to achieve all milestones. Interpretation Optimistic parental expectations may be adaptive for children with spina bifida and their families, although it is important for families to set realistic goals. Healthcare providers serve a key role in helping families of young people with spina bifida prepare for emerging adulthood. PMID:27651215

A comparison of accelerated solvent extraction, Soxhlet extraction, and ultrasonic-assisted extraction for analysis of terpenoids and sterols in tobacco.

PubMed

Shen, Jinchao; Shao, Xueguang

2005-11-01

The performance of accelerated solvent extraction in the analysis of terpenoids and sterols in tobacco samples was investigated and compared with those of Soxhlet extraction and ultrasonically assisted extraction with respect to yield, extraction time, reproducibility and solvent consumption. The results indicate that although the highest yield was achieved by Soxhlet extraction, ASE appears to be a promising alternative to classical methods since it is faster and uses less solvent, especially when applied to the investigation of large batch tobacco samples. However, Soxhlet extraction is still the preferred method for analyzing sterols since it gives a higher extraction efficiency than other methods.

Applying a 2D based CAD scheme for detecting micro-calcification clusters using digital breast tomosynthesis images: an assessment

NASA Astrophysics Data System (ADS)

Park, Sang Cheol; Zheng, Bin; Wang, Xiao-Hui; Gur, David

2008-03-01

Digital breast tomosynthesis (DBT) has emerged as a promising imaging modality for screening mammography. However, visually detecting micro-calcification clusters depicted on DBT images is a difficult task. Computer-aided detection (CAD) schemes for detecting micro-calcification clusters depicted on mammograms can achieve high performance and the use of CAD results can assist radiologists in detecting subtle micro-calcification clusters. In this study, we compared the performance of an available 2D based CAD scheme with one that includes a new grouping and scoring method when applied to both projection and reconstructed DBT images. We selected a dataset involving 96 DBT examinations acquired on 45 women. Each DBT image set included 11 low dose projection images and a varying number of reconstructed image slices ranging from 18 to 87. In this dataset 20 true-positive micro-calcification clusters were visually detected on the projection images and 40 were visually detected on the reconstructed images, respectively. We first applied the CAD scheme that was previously developed in our laboratory to the DBT dataset. We then tested a new grouping method that defines an independent cluster by grouping the same cluster detected on different projection or reconstructed images. We then compared four scoring methods to assess the CAD performance. The maximum sensitivity level observed for the different grouping and scoring methods were 70% and 88% for the projection and reconstructed images with a maximum false-positive rate of 4.0 and 15.9 per examination, respectively. This preliminary study demonstrates that (1) among the maximum, the minimum or the average CAD generated scores, using the maximum score of the grouped cluster regions achieved the highest performance level, (2) the histogram based scoring method is reasonably effective in reducing false-positive detections on the projection images but the overall CAD sensitivity is lower due to lower signal-to-noise ratio, and (3) CAD achieved higher sensitivity and higher false-positive rate (per examination) on the reconstructed images. We concluded that without changing the detection threshold or performing pre-filtering to possibly increase detection sensitivity, current CAD schemes developed and optimized for 2D mammograms perform relatively poorly and need to be re-optimized using DBT datasets and new grouping and scoring methods need to be incorporated into the schemes if these are to be used on the DBT examinations.

Deep convolutional neural networks as strong gravitational lens detectors

NASA Astrophysics Data System (ADS)

Schaefer, C.; Geiger, M.; Kuntzer, T.; Kneib, J.-P.

2018-03-01

Context. Future large-scale surveys with high-resolution imaging will provide us with approximately 105 new strong galaxy-scale lenses. These strong-lensing systems will be contained in large data amounts, however, which are beyond the capacity of human experts to visually classify in an unbiased way. Aim. We present a new strong gravitational lens finder based on convolutional neural networks (CNNs). The method was applied to the strong-lensing challenge organized by the Bologna Lens Factory. It achieved first and third place, respectively, on the space-based data set and the ground-based data set. The goal was to find a fully automated lens finder for ground-based and space-based surveys that minimizes human inspection. Methods: We compared the results of our CNN architecture and three new variations ("invariant" "views" and "residual") on the simulated data of the challenge. Each method was trained separately five times on 17 000 simulated images, cross-validated using 3000 images, and then applied to a test set with 100 000 images. We used two different metrics for evaluation, the area under the receiver operating characteristic curve (AUC) score, and the recall with no false positive (Recall0FP). Results: For ground-based data, our best method achieved an AUC score of 0.977 and a Recall0FP of 0.50. For space-based data, our best method achieved an AUC score of 0.940 and a Recall0FP of 0.32. Adding dihedral invariance to the CNN architecture diminished the overall score on space-based data, but achieved a higher no-contamination recall. We found that using committees of five CNNs produced the best recall at zero contamination and consistently scored better AUC than a single CNN. Conclusions: We found that for every variation of our CNN lensfinder, we achieved AUC scores close to 1 within 6%. A deeper network did not outperform simpler CNN models either. This indicates that more complex networks are not needed to model the simulated lenses. To verify this, more realistic lens simulations with more lens-like structures (spiral galaxies or ring galaxies) are needed to compare the performance of deeper and shallower networks.

Multiplex enrichment quantitative PCR (ME-qPCR): a high-throughput, highly sensitive detection method for GMO identification.

PubMed

Fu, Wei; Zhu, Pengyu; Wei, Shuang; Zhixin, Du; Wang, Chenguang; Wu, Xiyang; Li, Feiwu; Zhu, Shuifang

2017-04-01

Among all of the high-throughput detection methods, PCR-based methodologies are regarded as the most cost-efficient and feasible methodologies compared with the next-generation sequencing or ChIP-based methods. However, the PCR-based methods can only achieve multiplex detection up to 15-plex due to limitations imposed by the multiplex primer interactions. The detection throughput cannot meet the demands of high-throughput detection, such as SNP or gene expression analysis. Therefore, in our study, we have developed a new high-throughput PCR-based detection method, multiplex enrichment quantitative PCR (ME-qPCR), which is a combination of qPCR and nested PCR. The GMO content detection results in our study showed that ME-qPCR could achieve high-throughput detection up to 26-plex. Compared to the original qPCR, the Ct values of ME-qPCR were lower for the same group, which showed that ME-qPCR sensitivity is higher than the original qPCR. The absolute limit of detection for ME-qPCR could achieve levels as low as a single copy of the plant genome. Moreover, the specificity results showed that no cross-amplification occurred for irrelevant GMO events. After evaluation of all of the parameters, a practical evaluation was performed with different foods. The more stable amplification results, compared to qPCR, showed that ME-qPCR was suitable for GMO detection in foods. In conclusion, ME-qPCR achieved sensitive, high-throughput GMO detection in complex substrates, such as crops or food samples. In the future, ME-qPCR-based GMO content identification may positively impact SNP analysis or multiplex gene expression of food or agricultural samples. Graphical abstract For the first-step amplification, four primers (A, B, C, and D) have been added into the reaction volume. In this manner, four kinds of amplicons have been generated. All of these four amplicons could be regarded as the target of second-step PCR. For the second-step amplification, three parallels have been taken for the final evaluation. After the second evaluation, the final amplification curves and melting curves have been achieved.

Effects of Team-Based Learning on the Core Competencies of Nursing Students: A Quasi-Experimental Study.

PubMed

Lee, Kyung Eun

2018-04-01

An important goal of nursing education is helping students achieve core competencies efficiently. One proposed way of improving nursing education is team-based learning (TBL). The aim of this study was to assess the comparative effectiveness of TBL and lecture-style classes in terms of teaching core competencies in nursing education, which include clinical competence skills, problem-solving ability, communication competencies, critical thinking ability, and self-leadership. This quasi-experimental study enrolled 183 students as participants, with 95 and 88 in the experimental and control groups, respectively. These two groups attended 6 hours (2 hours weekly for 3 weeks) of TBL and lecture-style classes, respectively. Differences in core competencies between the two groups were compared before and after the intervention. The experimental group achieved significantly higher scores for clinical competence skills, communication competence, critical thinking ability, and self-leadership at posttest than at pretest, whereas the control group achieved significantly higher scores for clinical competence skills and critical thinking ability at posttest than at pretest. After the intervention, the experimental group had significantly better clinical competence skills, communication competence, and self-leadership than the control group. TBL is an effective approach method to teaching core competencies in nursing education.

Using sewage sludge pyrolytic gas to modify titanium alloy to obtain high-performance anodes in bio-electrochemical systems

NASA Astrophysics Data System (ADS)

Gu, Yuan; Ying, Kang; Shen, Dongsheng; Huang, Lijie; Ying, Xianbin; Huang, Haoqian; Cheng, Kun; Chen, Jiazheng; Zhou, Yuyang; Chen, Ting; Feng, Huajun

2017-12-01

Titanium is under consideration as a potential stable bio-anode because of its high conductivity, suitable mechanical properties, and electrochemical inertness in the operating potential window of bio-electrochemical systems; however, its application is limited by its poor electron-transfer capacity with electroactive bacteria and weak ability to form biofilms on its hydrophobic surface. This study reports an effective and low-cost way to convert a hydrophobic titanium alloy surface into a hydrophilic surface that can be used as a bio-electrode with higher electron-transfer rates. Pyrolytic gas of sewage sludge is used to modify the titanium alloy. The current generation, anodic biofilm formation surface, and hydrophobicity are systematically investigated by comparing bare electrodes with three modified electrodes. Maximum current density (15.80 A/m2), achieved using a modified electrode, is 316-fold higher than that of the bare titanium alloy electrode (0.05 A/m2) and that achieved by titanium alloy electrodes modified by other methods (12.70 A/m2). The pyrolytic gas-modified titanium alloy electrode can be used as a high-performance and scalable bio-anode for bio-electrochemical systems because of its high electron-transfer rates, hydrophilic nature, and ability to achieve high current density.

Chronic sleep reduction is associated with academic achievement and study concentration in higher education students.

PubMed

van der Heijden, Kristiaan B; Vermeulen, Marije C M; Donjacour, Claire E H M; Gordijn, Marijke C M; Hamburger, Hans L; Meijer, Anne M; van Rijn, Karin J; Vlak, Monique; Weysen, Tim

2018-04-01

Inadequate sleep impairs cognitive function and has been associated with worse academic achievement in higher education students; however, studies that control for relevant background factors and include knowledge on sleep hygiene are scarce. This study examined the association of chronic sleep reduction (i.e. symptoms of chronic sleep reduction such as shortness of sleep, sleepiness and irritation), subjective sleep quality and sleep hygiene knowledge with academic achievement (grades and study credits) and study concentration among 1378 higher education students (71% female, mean age 21.73 years, SD = 3.22) in the Netherlands. Demographic, health, lifestyle and study behaviour characteristics were included as covariates in hierarchical regression analyses. After controlling for significant covariates, only chronic sleep reduction remained a significant predictor of lower grades (last exam, average in current academic year). Better sleep quality and sleep hygiene knowledge were associated with better academic achievement, but significance was lost after controlling for covariates, except for a remaining positive association between sleep hygiene beliefs and grades in the current academic year. Moreover, better sleep quality and lower scores on chronic sleep reduction were associated with better study concentration after controlling for significant covariates. To conclude, chronic sleep reduction is associated with academic achievement and study concentration in higher education students. Inadequate sleep hygiene knowledge is moderately associated with worse academic achievement. Future research should investigate whether sleep hygiene interventions improve academic achievement in students of higher education. © 2017 European Sleep Research Society.

The effect of A teacher questioning strategy training program on teaching behavior, student achievement, and retention

NASA Astrophysics Data System (ADS)

Otto, Paul B.; Schuck, Robert F.

The use of questions in the classroom has been employed throughout the recorded history of teaching. One still hears the term Socratic method during discussions of questioning procedures. The use of teacher questions is presently viewed as a viable procedure for effective instruction. This study was conducted to investigate the feasibility of training teachers in the use of a questioning technique and the resultant effect upon student learning. The Post-Test Only Control Group Design was used in randomly assigning teachers and students to experimental and control groups. A group of teachers was trained in the use of a specific questioning technique. Follow-up periodic observations were made of questioning technique behavior while teaching science units to groups of students. Post-unit achievement tests were administered to the student groups to obtain evidence of a relationship between the implementation of specific types of teacher questions and student achievement and retention. Analysis of observation data indicated a higher use of managerial and rhetorical questions by the control group than the experimental group. The experimental group employed a greater number of recall and data gathering questions as well as higher order data processing and data verification type questions. The student posttest achievement scores for both units of instruction were greater for the experimental groups than for the control groups. The retention scores for both units were Beater for the experimental groups than for the control groups.

Process oriented guided inquiry learning (POGIL®) marginally effects student achievement measures but substantially increases the odds of passing a course.

PubMed

Walker, Lindsey; Warfa, Abdi-Rizak M

2017-01-01

While the inquiry approach to science teaching has been widely recommended as an epistemic mechanism to promote deep content understanding, there is also increased expectation that process and other transferable skills should be integral part of science pedagogy. To test the hypothesis that coupling process skills to content teaching impacts academic success measures, we meta-analyzed twenty-one studies (n = 21) involving 7876 students that compared Process Oriented Guided Inquiry Learning (POGIL), a pedagogy that provides opportunities for improving process skills during content learning through guided-inquiry activities, to standard lecture conditions. Based on conventional measures of class performance, POGIL had a small effect on achievement outcomes (effect size = 0.29, [95% CI = 0.15-0.43]) but substantially improved the odds of passing a class (odds ratio = 2.02, [95% CI: 1.45-2.83]). That is, participants in the POGIL pedagogy had higher odds of passing a course and roughly performed 0.3 standard deviations higher on achievement measures than participants in standard lectures. In relative risk terms, POGIL reduced the risk of failing a course by 38%. These findings suggest providing opportunities to improve process skills during class instruction does not inhibit content learning but enhances conventional success measures. We compare these findings with those of recent large meta-analysis that examined the effects of global active learning methods on achievement outcomes and course failure rates in science, technology, engineering, and mathematics (STEM) fields.

Profile of middle school students on scientific literacy achievements by using scientific literacy assessments (SLA)

NASA Astrophysics Data System (ADS)

Rachmatullah, Arif; Diana, Sariwulan; Rustaman, Nuryani Y.

2016-02-01

Along with the development of science and technology, the basic ability to read, write and count is not enough just to be able to survive in the modern era that surrounded by the products of science and technology. Scientific literacy is an ability that might be added as basic ability for human in the modern era. Recently, Fives et al. developed a new scientific literacy assessment for students, named as SLA (Scientific Literacy Assessment). A pilot study on the achievements of scientific literacy of middle school students in Sumedang using SLA was conducted to investigate the profile scientific literacy achievement of 223 middle school students in Sumedang, and compare the outcomes between genders (159 girls and 64 boys) and school accreditation (A and B) using a quantitative method with descriptive research-school survey. Based on the results, the average achievement of scientific literacy Sumedang middle school students is 45.21 and classified as the low category. The five components of scientific literacy, which is only one component in the medium category, namely science motivation and beliefs, and the four other components are in the low and very low category. Boys have higher scientific literacy, but the differences not statistically significant. Student's scientific literacy in an accredited school is higher than B, and the differences are statistically significant. Recommendation for further are: involve more research subjects, add more number of questions for each indicator, and conduct an independent research for each component.

Process oriented guided inquiry learning (POGIL®) marginally effects student achievement measures but substantially increases the odds of passing a course

PubMed Central

Walker, Lindsey

2017-01-01

While the inquiry approach to science teaching has been widely recommended as an epistemic mechanism to promote deep content understanding, there is also increased expectation that process and other transferable skills should be integral part of science pedagogy. To test the hypothesis that coupling process skills to content teaching impacts academic success measures, we meta-analyzed twenty-one studies (n = 21) involving 7876 students that compared Process Oriented Guided Inquiry Learning (POGIL), a pedagogy that provides opportunities for improving process skills during content learning through guided-inquiry activities, to standard lecture conditions. Based on conventional measures of class performance, POGIL had a small effect on achievement outcomes (effect size = 0.29, [95% CI = 0.15–0.43]) but substantially improved the odds of passing a class (odds ratio = 2.02, [95% CI: 1.45–2.83]). That is, participants in the POGIL pedagogy had higher odds of passing a course and roughly performed 0.3 standard deviations higher on achievement measures than participants in standard lectures. In relative risk terms, POGIL reduced the risk of failing a course by 38%. These findings suggest providing opportunities to improve process skills during class instruction does not inhibit content learning but enhances conventional success measures. We compare these findings with those of recent large meta-analysis that examined the effects of global active learning methods on achievement outcomes and course failure rates in science, technology, engineering, and mathematics (STEM) fields. PMID:29023502

Student achievement in science: A longitudinal look at individual and school differences

NASA Astrophysics Data System (ADS)

Martinez, Alina

The importance of science in today's technological society necessitates continued attention to students' experiences in science and specifically their achievement in science. There is a need to look at gender and race/ethnicity simultaneously when studying students' experiences in science and to explore factors related to higher achievement among students. Using data from the Longitudinal Study of American Youth, this study contributes to existing literature on student achievement in science by simultaneously exploring the effects of race/ethnicity and gender. Capitalizing on the availability of yearly science achievement scores, I present trajectories of student achievement from 7th to 12th grade. This study also includes an exploration of school effects. Overall, student achievement in science increases from 7th to 12th grade, although some leveling is seen in later grades. Growth in achievement differs by both gender and race/ethnicity, but racial/ethnic differences are larger than gender differences. Hispanic, Black, Asian, and White males score higher, on average, throughout the secondary grades than their female counterparts. Achievement scores of Asian students are consistently higher than White students, who in turn score higher than Hispanic and finally Black students. Both background and science-related factors help explain variation in achievement status and growth in achievement. Parental education is positively associated with achievement status among all groups except Black students for whom there is no effect of parental education. Science related resources in the home are positively associated with student achievement and the effect of these resources increases in later grades. Student achievement in science is also positively related to student course taking and attitude toward science. Furthermore, both the negative effect of viewing science as a male domain, which exists for males and females, and the positive effect of parental support for science increase in magnitude in later grades. Thirteen percent of the variation in achievement was found to occur between schools. At the school level, student/teacher ratio is positively related to student achievement in 7th grade and the percent of students who receive free lunch in a school is negatively related to achievement, but neither of these is related to growth in achievement over time.

Comparing Episodes of Mathematics Teaching for Higher Achievers in England and Germany

ERIC Educational Resources Information Center

Kelly, Peter; Kotthoff, Hans-Georg

2016-01-01

To illustrate similarities and differences in lower secondary level mathematics teaching with higher achievers and thereby explore privileging processes, we contrast a teaching episode in Baden-Württemberg, Germany with one in South West England. These have been selected from a larger study as typical within each region for higher achieving…

Transformation of the Fungal Soybean Pathogen Cercospora kikuchii with the Selectable Marker bar

PubMed Central

Upchurch, Robert G.; Meade, Maura J.; Hightower, Robin C.; Thomas, Robert S.; Callahan, Terrence M.

1994-01-01

An improved transformation protocol, utilizing selection for resistance to the herbicide bialaphos, has been developed for the plant pathogenic fungus Cercospora kikuchii. Stable, bialaphos-resistant transformants are recovered at frequencies eight times higher than those achieved with the previous system that was based on selection for benomyl resistance. In addition to C. kikuchii, this improved method can also be used to transform other species of Cercospora. Images PMID:16349469

Efficient Second Harmonic Generation From 2-(N,N-Dimethylamino)-5-Nitroacetanilide (DAN) Crystal Cored Fibres

NASA Astrophysics Data System (ADS)

Rush, James D.; Holdcroft, Geoffrey E.; Dunn, Peter L.

1989-03-01

The growth and characterisation of fibres containing a crystalline core of the nonlinear organic compound DAN in silica and higher refractive index capillaries is described. In addition to measuring the optical properties in transmission a method is described of measuring the sideways scatter from such fibres in order that a fuller understanding be made of factors which limit the achievement of very high SHG efficiencies.

JPRS Report, Soviet Union: Political Affairs

DTIC Science & Technology

1988-05-24

Azerbaijani Komsomol Resolution on Increasing Interaction [Editorial; KOMSOMOLETS 7 Apr 88] 47 Appeal to Armenian Komsomol Members for Discipline, Public...area, and certain of them, as V. S. Semenov recently said in VOPROSY FILOSOFII, "once again the ’first’ are already appealing to us to show boldness...and even of almost uncon- cealed appeals to higher administrative echelons to achieve the "brainwashing" of one’s opponents. The methods are still

A novel pretreatment method combining sealing technique with direct injection technique applied for improving biosafety.

PubMed

Wang, Xinyu; Gao, Jing-Lin; Du, Chaohui; An, Jing; Li, MengJiao; Ma, Haiyan; Zhang, Lina; Jiang, Ye

2017-01-01

People today have a stronger interest in the risk of biosafety in clinical bioanalysis. A safe, simple, effective method of preparation is needed urgently. To improve biosafety of clinical analysis, we used antiviral drugs of adefovir and tenofovir as model drugs and developed a safe pretreatment method combining sealing technique with direct injection technique. The inter- and intraday precision (RSD %) of the method were <4%, and the extraction recoveries ranged from 99.4 to 100.7%. Meanwhile, the results showed that standard solution could be used to prepare calibration curve instead of spiking plasma, acquiring more accuracy result. Compared with traditional methods, the novel method not only improved biosecurity of the pretreatment method significantly, but also achieved several advantages including higher precision, favorable sensitivity and satisfactory recovery. With these highly practical and desirable characteristics, the novel method may become a feasible platform in bioanalysis.

CS-AMPPred: An Updated SVM Model for Antimicrobial Activity Prediction in Cysteine-Stabilized Peptides

PubMed Central

Porto, William F.; Pires, Állan S.; Franco, Octavio L.

2012-01-01

The antimicrobial peptides (AMP) have been proposed as an alternative to control resistant pathogens. However, due to multifunctional properties of several AMP classes, until now there has been no way to perform efficient AMP identification, except through in vitro and in vivo tests. Nevertheless, an indication of activity can be provided by prediction methods. In order to contribute to the AMP prediction field, the CS-AMPPred (Cysteine-Stabilized Antimicrobial Peptides Predictor) is presented here, consisting of an updated version of the Support Vector Machine (SVM) model for antimicrobial activity prediction in cysteine-stabilized peptides. The CS-AMPPred is based on five sequence descriptors: indexes of (i) α-helix and (ii) loop formation; and averages of (iii) net charge, (iv) hydrophobicity and (v) flexibility. CS-AMPPred was based on 310 cysteine-stabilized AMPs and 310 sequences extracted from PDB. The polynomial kernel achieves the best accuracy on 5-fold cross validation (85.81%), while the radial and linear kernels achieve 84.19%. Testing in a blind data set, the polynomial and radial kernels achieve an accuracy of 90.00%, while the linear model achieves 89.33%. The three models reach higher accuracies than previously described methods. A standalone version of CS-AMPPred is available for download at and runs on any Linux machine. PMID:23240023

Compression techniques in tele-radiology

NASA Astrophysics Data System (ADS)

Lu, Tianyu; Xiong, Zixiang; Yun, David Y.

1999-10-01

This paper describes a prototype telemedicine system for remote 3D radiation treatment planning. Due to voluminous medical image data and image streams generated in interactive frame rate involved in the application, the importance of deploying adjustable lossy to lossless compression techniques is emphasized in order to achieve acceptable performance via various kinds of communication networks. In particular, the compression of the data substantially reduces the transmission time and therefore allows large-scale radiation distribution simulation and interactive volume visualization using remote supercomputing resources in a timely fashion. The compression algorithms currently used in the software we developed are JPEG and H.263 lossy methods and Lempel-Ziv (LZ77) lossless methods. Both objective and subjective assessment of the effect of lossy compression methods on the volume data are conducted. Favorable results are obtained showing that substantial compression ratio is achievable within distortion tolerance. From our experience, we conclude that 30dB (PSNR) is about the lower bound to achieve acceptable quality when applying lossy compression to anatomy volume data (e.g. CT). For computer simulated data, much higher PSNR (up to 100dB) is expectable. This work not only introduces such novel approach for delivering medical services that will have significant impact on the existing cooperative image-based services, but also provides a platform for the physicians to assess the effects of lossy compression techniques on the diagnostic and aesthetic appearance of medical imaging.

The Effect of Teaching Strategies and Curiosity on Students' Achievement in Reading Comprehension

ERIC Educational Resources Information Center

Gurning, Busmin; Siregar, Aguslani

2017-01-01

The objectives of this study were to find out whether 1) students' achievement in reading comprehension taught by using INSERT strategy was higher than those taught by using SQ3R strategy, 2) Students' achievement in reading comprehension having high curiosity was higher than those having low curiosity, 3) there was an interaction between teaching…

Does the Quality of SafeTalk Motivational Interviewing Counseling Predict Sexual Behavior Outcomes among People Living with HIV?

PubMed Central

Grodensky, Catherine; Golin, Carol; Parikh, Megha A.; Ochtera, Rebecca; Kincaid, Carlye; Groves, Jennifer; Widman, Laura; Suchindran, Chirayath; McGirt, Camille; Amola, Kemi; Bradley-Bull, Steven

2017-01-01

Objective Although past research has demonstrated a link between the quality of motivational interviewing (MI) counseling and client behavior change, this relationship has not been examined in the context of sexual risk behavior among people living with HIV/AIDS. We studied MI quality and unprotected anal/vaginal intercourse (UAVI) in the context of SafeTalk, an evidence-based secondary HIV prevention intervention. Methods We used a structured instrument (the MISC 2.0 coding system) as well as a client-reported instrument to rate intervention sessions on aspects of MI quality. Then we correlated client-reported UAVI with specific counseling behaviors and the proportion of interactions that achieved MI quality benchmarks. Results/Conclusion Higher MISC-2.0 global ratings and a higher ratio of reflections to questions both significantly predicted fewer UAVI acts at 8-month follow-up. Analysis of client ratings, which was more exploratory, showed that clients who rated their sessions higher in counselor acceptance, client disclosure, and relevance reported higher numbers of UAVIs, whereas clients who selected higher ratings for perceived benefit were more likely to have fewer UAVI episodes. Practice Implications Further research is needed to determine the best methods of translating information about MI quality into dissemination of effective MI interventions with people living with HIV. PMID:27567497

Nitrogen removal from wastewater by a catalytic oxidation method.

PubMed

Huang, T L; Macinnes, J M; Cliffe, K R

2001-06-01

The ammonia-containing waste produced in industries is usually characterized by high concentration and high temperature, and is not treatable by biological methods directly. In this study, a hydrophobic Pt/SDB catalyst was first used in a trickle-bed reactor to remove ammonia from wastewater. In the reactor, both stripping and catalytic oxidation occur simultaneously. It was found that higher temperature and higher oxygen partial pressure enhanced the ammonia removal. A reaction pathway, which involves oxidizing ammonia to nitric oxide, which then further reacts with ammonia to produce nitrogen and water, was confirmed. Small amounts of by-products, nitrites and nitrates were also detected in the resultant reaction solution. These compounds came from the absorption of nitrogen oxides. Both the minimum NO2- selectivity and maximum ammonia removal were achieved when the resultant pH of treated water was near 7.5 for a feed of unbuffered ammonia solution.

Flower-shaped ZnO nanocrystallite aggregates synthesized through a template-free aqueous solution method for dye-sensitized solar cells

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chang, Wei-Chen, E-mail: changpeter@iner.gov.tw; Institute of Nuclear Energy Research, Atomic Energy Council, Executive Yuan, 1000 Wenhua Rd., Chiaan Village, Lungtan, Taoyuan 325, Taiwan; Chen, Hung-Shuo

Hierarchically structured flower-shaped aggregates composed of ZnO nanocrystals were synthesized through a template-free aqueous solution method. The synthesized nanocrystallite aggregates were demonstrated to be promising photoanode materials for dye-sensitized solar cells (DSSCs). Compared with commercially available ZnO nanoparticles (ZnONPs), the flower-like aggregates (ZnONFs), each having an overall dimension of 400–600 nm, exhibited similar dye loading but higher light-scattering ability, which led to a substantial increase in the light-harvesting efficiency of resulting cells. The unique morphology of ZnONFs also boosted the absorbed photon-to-electric current generation efficiency. Consequently, DSSCs constructed from ZnONFs showed significantly improved photocurrent and achieved an overall conversion efficiency ofmore » 4.42%, which was 47% higher than that attained by ZnONP-based cells.« less

A novel Fast Gas Chromatography based technique for higher time resolution measurements of speciated monoterpenes in air

NASA Astrophysics Data System (ADS)

Jones, C. E.; Kato, S.; Nakashima, Y.; Kajii, Y.

2013-12-01

Biogenic emissions supply the largest fraction of non-methane volatile organic compounds (VOC) from the biosphere to the atmospheric boundary layer, and typically comprise a complex mixture of reactive terpenes. Due to this chemical complexity, achieving comprehensive measurements of biogenic VOC (BVOC) in air within a satisfactory time resolution is analytically challenging. To address this, we have developed a novel, fully automated Fast Gas Chromatography (Fast-GC) based technique to provide higher time resolution monitoring of monoterpenes (and selected other C9-C15 terpenes) during plant emission studies and in ambient air. To our knowledge, this is the first study to apply a Fast-GC based separation technique to achieve quantification of terpenes in air. Three chromatography methods have been developed for atmospheric terpene analysis under different sampling scenarios. Each method facilitates chromatographic separation of selected BVOC within a significantly reduced analysis time compared to conventional GC methods, whilst maintaining the ability to quantify individual monoterpene structural isomers. Using this approach, the C10-C15 BVOC composition of single plant emissions may be characterised within a ~ 14 min analysis time. Moreover, in situ quantification of 12 monoterpenes in unpolluted ambient air may be achieved within an ~ 11 min chromatographic separation time (increasing to ~ 19 min when simultaneous quantification of multiple oxygenated C9-C10 terpenoids is required, and/or when concentrations of anthropogenic VOC are significant). This corresponds to a two- to fivefold increase in measurement frequency compared to conventional GC methods. Here we outline the technical details and analytical capability of this chromatographic approach, and present the first in situ Fast-GC observations of 6 monoterpenes and the oxygenated BVOC linalool in ambient air. During this field deployment within a suburban forest ~ 30 km west of central Tokyo, Japan, the Fast-GC limit of detection with respect to monoterpenes was 4-5 ppt, and the agreement between Fast-GC and PTR-MS derived total monoterpene mixing ratios was consistent with previous GC/PTR-MS comparisons. The measurement uncertainties associated with the Fast-GC quantification of monoterpenes are ≤ 10%, while larger uncertainties (up to ~ 25%) are associated with the OBVOC and sesquiterpene measurements.

Ensemble-based prediction of RNA secondary structures.

PubMed

Aghaeepour, Nima; Hoos, Holger H

2013-04-24

Accurate structure prediction methods play an important role for the understanding of RNA function. Energy-based, pseudoknot-free secondary structure prediction is one of the most widely used and versatile approaches, and improved methods for this task have received much attention over the past five years. Despite the impressive progress that as been achieved in this area, existing evaluations of the prediction accuracy achieved by various algorithms do not provide a comprehensive, statistically sound assessment. Furthermore, while there is increasing evidence that no prediction algorithm consistently outperforms all others, no work has been done to exploit the complementary strengths of multiple approaches. In this work, we present two contributions to the area of RNA secondary structure prediction. Firstly, we use state-of-the-art, resampling-based statistical methods together with a previously published and increasingly widely used dataset of high-quality RNA structures to conduct a comprehensive evaluation of existing RNA secondary structure prediction procedures. The results from this evaluation clarify the performance relationship between ten well-known existing energy-based pseudoknot-free RNA secondary structure prediction methods and clearly demonstrate the progress that has been achieved in recent years. Secondly, we introduce AveRNA, a generic and powerful method for combining a set of existing secondary structure prediction procedures into an ensemble-based method that achieves significantly higher prediction accuracies than obtained from any of its component procedures. Our new, ensemble-based method, AveRNA, improves the state of the art for energy-based, pseudoknot-free RNA secondary structure prediction by exploiting the complementary strengths of multiple existing prediction procedures, as demonstrated using a state-of-the-art statistical resampling approach. In addition, AveRNA allows an intuitive and effective control of the trade-off between false negative and false positive base pair predictions. Finally, AveRNA can make use of arbitrary sets of secondary structure prediction procedures and can therefore be used to leverage improvements in prediction accuracy offered by algorithms and energy models developed in the future. Our data, MATLAB software and a web-based version of AveRNA are publicly available at http://www.cs.ubc.ca/labs/beta/Software/AveRNA.

Predictors of no-scalpel vasectomy acceptance in Karimnagar district, Andhra Pradesh

PubMed Central

Valsangkar, Sameer; Sai, Surendranath K.; Bele, Samir D.; Bodhare, Trupti N.

2012-01-01

Introduction: Karimnagar District has consistently achieved highest rates of no-scalpel vasectomy (NSV) in the past decade when compared to state and national rates. This study was conducted to elucidate the underlying causes for higher acceptance of NSV in the district. Materials and Methods: A community-based, case control study was conducted. Sampling techniques used were purposive and simple random sampling. A semi-structured questionnaire was used to evaluate the socio-demographic, family characteristics, contraceptive history and predictors of contraceptive choice in 116 NSV acceptors and 120 other contraceptive users (OCUs). Postoperative complications and experiences were ascertained in NSV acceptors. Results: Age (χ2=11.79, P value = 0.008), literacy (χ2=17.95, P value = 0.03), duration of marriage (χ2=14.23, P value = 0.008) and number of children (χ2=10.45, P value = 0.01) were significant for acceptance of NSV. Among the predictors, method suggested by peer/ health worker (OR = 1.5, P value = 0.01), method does not require regular intervention (OR = 1.3, P value = 0.004) and permanence of the method (OR = 1.2, P value = 0.031) were significant. Acceptors were most satisfied with the shorter duration required to return to work and the most common complication was persistent postoperative pain among 12 (10.34%) of the acceptors. Conclusion: Advocating and implementing family planning is of high significance in view of the population growth in India and drawing from the demographic profile, predictors, pool of trainers and experiences in Karimnagar District, a similar achievement of higher rates of this simple procedure with few complications can be replicated. PMID:23204657

A Novel Azimuth Super-Resolution Method by Synthesizing Azimuth Bandwidth of Multiple Tracks of Airborne Stripmap SAR Data

PubMed Central

Wang, Yan; Li, Jingwen; Sun, Bing; Yang, Jian

2016-01-01

Azimuth resolution of airborne stripmap synthetic aperture radar (SAR) is restricted by the azimuth antenna size. Conventionally, a higher azimuth resolution should be achieved by employing alternate modes that steer the beam in azimuth to enlarge the synthetic antenna aperture. However, if a data set of a certain region, consisting of multiple tracks of airborne stripmap SAR data, is available, the azimuth resolution of specific small region of interest (ROI) can be conveniently improved by a novel azimuth super-resolution method as introduced by this paper. The proposed azimuth super-resolution method synthesize the azimuth bandwidth of the data selected from multiple discontinuous tracks and contributes to a magnifier-like function with which the ROI can be further zoomed in with a higher azimuth resolution than that of the original stripmap images. Detailed derivation of the azimuth super-resolution method, including the steps of two-dimensional dechirping, residual video phase (RVP) removal, data stitching and data correction, is provided. The restrictions of the proposed method are also discussed. Lastly, the presented approach is evaluated via both the single- and multi-target computer simulations. PMID:27304959

Mother-adolescent language proficiency and adolescent academic and emotional adjustment among Chinese American families.

PubMed

Liu, Lisa L; Benner, Aprile D; Lau, Anna S; Kim, Su Yeong

2009-04-01

This study examined the role of adolescents' and mothers' self-reports of English and heritage language proficiency in youth's academic and emotional adjustment among 444 Chinese American families. Adolescents who were proficient in English tended to exhibit higher reading achievement scores, math achievement scores, and overall GPA. Mothers who were English proficient tended to have children with higher academic achievement and fewer depressive symptoms. Results also indicated that adolescents' heritage language maintenance was associated with positive adjustment, particularly amongst foreign-born youth and for youth whose parents were highly proficient in the heritage language. Mother-adolescent match in heritage language proficiency was related to higher math achievement scores and overall GPA. Additionally, higher heritage language proficiency was associated with fewer depressive symptoms for foreign-born but not U.S.-born youth. Overall, the findings suggest that proficiency in both the English and heritage language may confer advantages to Chinese American youth.

Effects of a free school breakfast programme on school attendance, achievement, psychosocial function, and nutrition: a stepped wedge cluster randomised trial

PubMed Central

2010-01-01

Background Approximately 55,000 children in New Zealand do not eat breakfast on any given day. Regular breakfast skipping has been associated with poor diets, higher body mass index, and adverse effects on children's behaviour and academic performance. Research suggests that regular breakfast consumption can improve academic performance, nutrition and behaviour. This paper describes the protocol for a stepped wedge cluster randomised trial of a free school breakfast programme. The aim of the trial is to determine the effects of the breakfast intervention on school attendance, achievement, psychosocial function, dietary habits and food security. Methods/Design Sixteen primary schools in the North Island of New Zealand will be randomised in a sequential stepped wedge design to a free before-school breakfast programme consisting of non-sugar coated breakfast cereal, milk products, and/or toast and spreads. Four hundred children aged 5-13 years (approximately 25 per school) will be recruited. Data collection will be undertaken once each school term over the 2010 school year (February to December). The primary trial outcome is school attendance, defined as the proportion of students achieving an attendance rate of 95% or higher. Secondary outcomes are academic achievement (literacy, numeracy, self-reported grades), sense of belonging at school, psychosocial function, dietary habits, and food security. A concurrent process evaluation seeks information on parents', schools' and providers' perspectives of the breakfast programme. Discussion This randomised controlled trial will provide robust evidence of the effects of a school breakfast programme on students' attendance, achievement and nutrition. Furthermore the study provides an excellent example of the feasibility and value of the stepped wedge trial design in evaluating pragmatic public health intervention programmes. Trial Registration Number Australian New Zealand Clinical Trials Registry (ANZCTR) - ACTRN12609000854235 PMID:21114862

An efficient scheme for automatic web pages categorization using the support vector machine

NASA Astrophysics Data System (ADS)

Bhalla, Vinod Kumar; Kumar, Neeraj

2016-07-01

In the past few years, with an evolution of the Internet and related technologies, the number of the Internet users grows exponentially. These users demand access to relevant web pages from the Internet within fraction of seconds. To achieve this goal, there is a requirement of an efficient categorization of web page contents. Manual categorization of these billions of web pages to achieve high accuracy is a challenging task. Most of the existing techniques reported in the literature are semi-automatic. Using these techniques, higher level of accuracy cannot be achieved. To achieve these goals, this paper proposes an automatic web pages categorization into the domain category. The proposed scheme is based on the identification of specific and relevant features of the web pages. In the proposed scheme, first extraction and evaluation of features are done followed by filtering the feature set for categorization of domain web pages. A feature extraction tool based on the HTML document object model of the web page is developed in the proposed scheme. Feature extraction and weight assignment are based on the collection of domain-specific keyword list developed by considering various domain pages. Moreover, the keyword list is reduced on the basis of ids of keywords in keyword list. Also, stemming of keywords and tag text is done to achieve a higher accuracy. An extensive feature set is generated to develop a robust classification technique. The proposed scheme was evaluated using a machine learning method in combination with feature extraction and statistical analysis using support vector machine kernel as the classification tool. The results obtained confirm the effectiveness of the proposed scheme in terms of its accuracy in different categories of web pages.

High count-rate study of two TES x-ray microcalorimeters with different transition temperatures

NASA Astrophysics Data System (ADS)

Lee, Sang-Jun; Adams, Joseph S.; Bandler, Simon R.; Betancourt-Martinez, Gabriele L.; Chervenak, James A.; Eckart, Megan E.; Finkbeiner, Fred M.; Kelley, Richard L.; Kilbourne, Caroline A.; Porter, Frederick S.; Sadleir, John E.; Smith, Stephen J.; Wassell, Edward J.

2017-10-01

We have developed transition-edge sensor (TES) microcalorimeter arrays with high count-rate capability and high energy resolution to carry out x-ray imaging spectroscopy observations of various astronomical sources and the Sun. We have studied the dependence of the energy resolution and throughput (fraction of processed pulses) on the count rate for such microcalorimeters with two different transition temperatures (T c). Devices with both transition temperatures were fabricated within a single microcalorimeter array directly on top of a solid substrate where the thermal conductance of the microcalorimeter is dependent upon the thermal boundary resistance between the TES sensor and the dielectric substrate beneath. Because the thermal boundary resistance is highly temperature dependent, the two types of device with different T cs had very different thermal decay times, approximately one order of magnitude different. In our earlier report, we achieved energy resolutions of 1.6 and 2.3 eV at 6 keV from lower and higher T c devices, respectively, using a standard analysis method based on optimal filtering in the low flux limit. We have now measured the same devices at elevated x-ray fluxes ranging from 50 Hz to 1000 Hz per pixel. In the high flux limit, however, the standard optimal filtering scheme nearly breaks down because of x-ray pile-up. To achieve the highest possible energy resolution for a fixed throughput, we have developed an analysis scheme based on the so-called event grade method. Using the new analysis scheme, we achieved 5.0 eV FWHM with 96% throughput for 6 keV x-rays of 1025 Hz per pixel with the higher T c (faster) device, and 5.8 eV FWHM with 97% throughput with the lower T c (slower) device at 722 Hz.

Soy Mujer!: A Case Study for Understanding Latina Achievement in Higher Education

ERIC Educational Resources Information Center

Stephens, Elizabeth

2012-01-01

Latinas are one of fastest growing segments of the population in the United States, which clearly shows a need to better understand and support education for Latinas within higher education. This study sought to understand the process for and experience of Latinas' academic achievement within higher education. The study focused particularly on the…

[Biometric identification method for ECG based on the piecewise linear representation (PLR) and dynamic time warping (DTW)].

PubMed

Yang, Licai; Shen, Jun; Bao, Shudi; Wei, Shoushui

2013-10-01

To treat the problem of identification performance and the complexity of the algorithm, we proposed a piecewise linear representation and dynamic time warping (PLR-DTW) method for ECG biometric identification. Firstly we detected R peaks to get the heartbeats after denoising preprocessing. Then we used the PLR method to keep important information of an ECG signal segment while reducing the data dimension at the same time. The improved DTW method was used for similarity measurements between the test data and the templates. The performance evaluation was carried out on the two ECG databases: PTB and MIT-BIH. The analystic results showed that compared to the discrete wavelet transform method, the proposed PLR-DTW method achieved a higher accuracy rate which is nearly 8% of rising, and saved about 30% operation time, and this demonstrated that the proposed method could provide a better performance.

TU-F-BRF-06: 3D Pancreas MRI Segmentation Using Dictionary Learning and Manifold Clustering

DOE Office of Scientific and Technical Information (OSTI.GOV)

Gou, S; Rapacchi, S; Hu, P

2014-06-15

Purpose: The recent advent of MRI guided radiotherapy machines has lent an exciting platform for soft tissue target localization during treatment. However, tools to efficiently utilize MRI images for such purpose have not been developed. Specifically, to efficiently quantify the organ motion, we develop an automated segmentation method using dictionary learning and manifold clustering (DLMC). Methods: Fast 3D HASTE and VIBE MR images of 2 healthy volunteers and 3 patients were acquired. A bounding box was defined to include pancreas and surrounding normal organs including the liver, duodenum and stomach. The first slice of the MRI was used for dictionarymore » learning based on mean-shift clustering and K-SVD sparse representation. Subsequent images were iteratively reconstructed until the error is less than a preset threshold. The preliminarily segmentation was subject to the constraints of manifold clustering. The segmentation results were compared with the mean shift merging (MSM), level set (LS) and manual segmentation methods. Results: DLMC resulted in consistently higher accuracy and robustness than comparing methods. Using manual contours as the ground truth, the mean Dices indices for all subjects are 0.54, 0.56 and 0.67 for MSM, LS and DLMC, respectively based on the HASTE image. The mean Dices indices are 0.70, 0.77 and 0.79 for the three methods based on VIBE images. DLMC is clearly more robust on the patients with the diseased pancreas while LS and MSM tend to over-segment the pancreas. DLMC also achieved higher sensitivity (0.80) and specificity (0.99) combining both imaging techniques. LS achieved equivalent sensitivity on VIBE images but was more computationally inefficient. Conclusion: We showed that pancreas and surrounding normal organs can be reliably segmented based on fast MRI using DLMC. This method will facilitate both planning volume definition and imaging guidance during treatment.« less

Effects of individualized assignments on biology achievement

NASA Astrophysics Data System (ADS)

Kremer, Philip L.

A pretest-posttest, randomized, two groups, experimental, factorial design compared effects of detailed and nondetailed assignments on biology achievement over seven and a half months. Detailed assignments (favoring field independence and induction) employed block diagrams and stepwise directions. Nondetailed assignments (favoring field dependence and deduction) virtually lacked these. The accessible population was 101 tenth grade preparatory school male students. The 95 students enrolled in first year biology constituted the sample. Two by three ANOVA was done on residualized posttest score means of the students. Totally, the detailed students achieved significantly higher than the nondetailed students. This significantly higher achievement was only true of detailed students in the middle thirds of the deviation intelligence quotient (DIQ) range and of the grade point average (G.P.A.) range after the breakdown into upper, middle, and lower thirds of intellectual capability (ability and achievement). The upper third detailed DIQ grouping indirectly achieved higher than its peers, whereas the lower detailed DIQ third achieved lower than its peers. Thus, high capability students apparently benefit from flow and block diagrams, inductions, field independence, and high structure, whereas low capability students may be hindered by these.

Physical education and academic achievement in elementary school: data from the early childhood longitudinal study.

PubMed

Carlson, Susan A; Fulton, Janet E; Lee, Sarah M; Maynard, L Michele; Brown, David R; Kohl, Harold W; Dietz, William H

2008-04-01

We examined the association between time spent in physical education and academic achievement in a longitudinal study of students in kindergarten through fifth grade. We used data from the Early Childhood Longitudinal Study, Kindergarten Class of 1998 to 1999, which employed a multistage probability design to select a nationally representative sample of students in kindergarten (analytic sample = 5316). Time spent in physical education (minutes per week) was collected from classroom teachers, and academic achievement (mathematics and reading) was scored on an item response theory scale. A small but significant benefit for academic achievement in mathematics and reading was observed for girls enrolled in higher amounts (70-300 minutes per week) of physical education (referent: 0-35 minutes per week). Higher amounts of physical education were not positively or negatively associated with academic achievement among boys. Among girls, higher amounts of physical education may be associated with an academic benefit. Physical education did not appear to negatively affect academic achievement in elementary school students. Concerns about adverse effects on achievement may not be legitimate reasons to limit physical education programs.

Stable same-sex friendships with higher achieving partners promote mathematical reasoning in lower achieving primary school children.

PubMed

DeLay, Dawn; Laursen, Brett; Kiuru, Noona; Poikkeus, Anna-Maija; Aunola, Kaisa; Nurmi, Jari-Erik

2015-11-01

This study was designed to investigate friend influence over mathematical reasoning in a sample of 374 children in 187 same-sex friend dyads (184 girls in 92 friendships; 190 boys in 95 friendships). Participants completed surveys that measured mathematical reasoning in the 3rd grade (approximately 9 years old) and 1 year later in the 4th grade (approximately 10 years old). Analyses designed for dyadic data (i.e., longitudinal actor-partner interdependence model) indicated that higher achieving friends influenced the mathematical reasoning of lower achieving friends, but not the reverse. Specifically, greater initial levels of mathematical reasoning among higher achieving partners in the 3rd grade predicted greater increases in mathematical reasoning from 3rd grade to 4th grade among lower achieving partners. These effects held after controlling for peer acceptance and rejection, task avoidance, interest in mathematics, maternal support for homework, parental education, length of the friendship, and friendship group norms on mathematical reasoning. © 2015 The British Psychological Society.

Stable Same-Sex Friendships with Higher Achieving Partners Promote Mathematical Reasoning in Lower Achieving Primary School Children

PubMed Central

DeLay, Dawn; Laursen, Brett; Kiuru, Noona; Poikkeus, Anna-Maija; Aunola, Kaisa; Nurmi, Jari-Erik

2015-01-01

This study is designed to investigate friend influence over mathematical reasoning in a sample of 374 children in 187 same-sex friend dyads (184 girls in 92 friendships; 190 boys in 95 friendships). Participants completed surveys that measured mathematical reasoning in the 3rd grade (approximately 9 years old) and one year later in the 4th grade (approximately 10 years old). Analyses designed for dyadic data (i.e., longitudinal Actor-Partner Interdependence Models) indicated that higher achieving friends influenced the mathematical reasoning of lower achieving friends, but not the reverse. Specifically, greater initial levels of mathematical reasoning among higher achieving partners in the 3rd grade predicted greater increases in mathematical reasoning from 3rd grade to 4th grade among lower achieving partners. These effects held after controlling for peer acceptance and rejection, task avoidance, interest in mathematics, maternal support for homework, parental education, length of the friendship, and friendship group norms on mathematical reasoning. PMID:26402901

National GDP, Science Interest and Science Achievement: A Person-by-Nation Interaction

PubMed Central

Drob, Elliot M. Tucker; Cheung, Amanda K.; Briley, Daniel A.

2014-01-01

Maximizing science achievement is a critical target of educational policy, with important implications for national and international economic and technological competitiveness. Previous research has identified both science interest and socioeconomic status (SES) as robust predictors of science achievement, but little research has examined their joint effects. In a dataset drawn from approximately 400,000 high school students from 57 countries, we document large interest by SES and interest by per capita gross domestic product (GDP) interactions in the prediction of science achievement. Student interest in science is a substantially stronger predictor of science achievement in higher socioeconomic contexts and in higher GDP nations. Our results are consistent with the hypothesis that, in higher opportunity contexts, motivational factors play larger roles in learning and achievement. They add to the growing body of evidence indicating that substantial cross national differences in psychological effect sizes are not simply a logical possibility, but in many cases, an empirical reality. PMID:25304883

Gross domestic product, science interest, and science achievement: a person × nation interaction.

PubMed

Tucker-Drob, Elliot M; Cheung, Amanda K; Briley, Daniel A

2014-11-01

Maximizing science achievement is a critical target of educational policy and has important implications for national and international economic and technological competitiveness. Previous research has identified both science interest and socioeconomic status (SES) as robust predictors of science achievement, but little research has examined their joint effects. In a data set drawn from approximately 400,000 high school students from 57 countries, we documented large Science Interest × SES and Science Interest × Per Capita Gross Domestic Product (GDP) interactions in the prediction of science achievement. Student interest in science is a substantially stronger predictor of science achievement in higher socioeconomic contexts and in higher-GDP nations. Our results are consistent with the hypothesis that in higher-opportunity contexts, motivational factors play larger roles in learning and achievement. They add to the growing body of evidence indicating that substantial cross-national differences in psychological effect sizes are not simply a logical possibility but, in many cases, an empirical reality. © The Author(s) 2014.

Interferon-free treatment for patients with chronic hepatitis C and autoimmune liver disease: higher SVR rates with special precautions for deterioration of autoimmune hepatitis

PubMed Central

Kanda, Tatsuo; Yasui, Shin; Nakamura, Masato; Nakamoto, Shingo; Takahashi, Koji; Wu, Shuang; Sasaki, Reina; Haga, Yuki; Ogasawara, Sadahisa; Saito, Tomoko; Kobayashi, Kazufumi; Kiyono, Soichiro; Ooka, Yoshihiko; Suzuki, Eiichiro; Chiba, Tetsuhiro; Maruyama, Hitoshi; Imazeki, Fumio; Moriyama, Mitsuhiko; Kato, Naoya

2018-01-01

Background Interferon-free treatment can achieve higher sustained virological response (SVR) rates, even in patients in whom hepatitis C virus (HCV) could not be eradicated in the interferon treatment era. Immune restoration in the liver is occasionally associated with HCV infection. We examined the safety and effects of interferon-free regimens on HCV patients with autoimmune liver diseases. Results All 7 HCV patients with autoimmune hepatitis (AIH) completed treatment and achieved SVR. Three patients took prednisolone (PSL) at baseline, and 3 did not take PSL during interferon-free treatment. In one HCV patient with AIH and cirrhosis, PSL were not administered at baseline, but she needed to take 40 mg/day PSL at week 8 for liver dysfunction. She also complained back pain and was diagnosed with vasospastic angina by coronary angiography at week 11. However, she completed interferon-free treatment. All 5 HCV patients with primary biliary cholangitis (PBC) completed treatment and achieved SVR. Three of these HCV patients with PBC were treated with UDCA during interferon-free treatment. Conclusions Interferon-free regimens could result in higher SVR rates in HCV patients with autoimmune liver diseases. As interferon-free treatment for HCV may have an effect on hepatic immunity and activity of the autoimmune liver diseases, careful attention should be paid to unexpected adverse events in their treatments. Methods Total 12 patients with HCV and autoimmune liver diseases [7 AIH and PBC], who were treated with interferon-free regimens, were retrospectively analyzed. PMID:29545925

Comparison of textbook passages, nonfiction trade book passages and fiction trade book passages as instructional tools for learning science

NASA Astrophysics Data System (ADS)

Kelly, Cynthia

This study examined the impact of different types of text on student achievement in elementary school science. Gender was also examined to see if the type of text passage read had any differential effect on boys' and girls' achievement. This study was a pretest/posttest/retention test design. Eighty-four fourth grade students from a public charter elementary school in South Florida were randomly assigned a passage from a physical science textbook, a physical science nonfiction trade book, a physical science fiction trade book, a biological science textbook or a biological science nonfiction trade book. Results in the physical science content area revealed that students in the textbook passage group had higher posttest and retention test results than students in the nonfiction and fiction trade book passage groups. There was no difference on the posttest results of students in the biological science textbook and nonfiction trade book passage groups. Students in the biological science textbook passage group had higher retention results than students in the biological science nonfiction passage group. Gender results in the physical science content area revealed that boys had a higher retention score than girls in the fiction trade book passage group. There were no gender achievement differences as a result of the text passage read in the biological science content area. It was concluded that no definitive answer as to the efficacy of textbooks versus trade books was possible based upon results of the study. Recommendations for future research include examining the effects of different types of texts in conjunction with other authentic teaching methods.

A nitric oxide concentration clamp.

PubMed

Zhelyaskov, V R; Godwin, D W

1999-10-01

We report a new method of generating nitric oxide (NO) that possesses several advantages for experimental use. This method consists of a photolysis chamber where NO is released by illuminating photolabile NO donors with light from a xenon lamp, in conjunction with feedback control. Control of the photolysis light was achieved by selectively gating light projected through a shutter before the light was launched into a light guide that conveyed the light to the photolysis chamber. By gating the light in proportion to a sensor that reported nearly instantaneous concentration from the photolysis chamber, a criterion NO concentration could be achieved, which could be easily adjusted to higher or lower criterion levels. To denote the similarity of this process with the electrophysiological process of voltage clamp, we term this process a concentration "clamp." This development enhances the use of the fiber-optic-based system for NO delivery and should enable the execution of experiments where the in situ concentration of NO is particularly critical, such as in biological preparations. Copyright 1999 Academic Press.

Modeling and Analysis of the Static Characteristics and Dynamic Responses of Herringbone-grooved Thrust Bearings

NASA Astrophysics Data System (ADS)

Yu, Yunluo; Pu, Guang; Jiang, Kyle

2017-12-01

This paper describes a theoretical investigation of static and dynamic characteristics of herringbone-grooved air thrust bearings. Firstly, Finite Difference Method (FDM) and Finite Volume Method (FVM) are used in combination to solve the non-linear Reynolds equation and to find the pressure distribution of the film and the total loading capacity of the bearing. The influence of design parameters on air film gap characteristics, including the air film thickness, depth of the groove and rotating speed, are analyzed based on the FDM model. The simulation results show that hydrostatic thrust bearings can achieve a better load capacity with less air consumption than herringbone grooved thrust bearings at low compressibility number; herringbone grooved thrust bearings can achieve a higher load capacity but with more air consumption than hydrostatic thrust bearing at high compressibility number; herringbone grooved thrust bearings would lose stability at high rotating speeds, and the stability increases with the depth of the grooves.

Improved key-rate bounds for practical decoy-state quantum-key-distribution systems

NASA Astrophysics Data System (ADS)

Zhang, Zhen; Zhao, Qi; Razavi, Mohsen; Ma, Xiongfeng

2017-01-01

The decoy-state scheme is the most widely implemented quantum-key-distribution protocol in practice. In order to account for the finite-size key effects on the achievable secret key generation rate, a rigorous statistical fluctuation analysis is required. Originally, a heuristic Gaussian-approximation technique was used for this purpose, which, despite its analytical convenience, was not sufficiently rigorous. The fluctuation analysis has recently been made rigorous by using the Chernoff bound. There is a considerable gap, however, between the key-rate bounds obtained from these techniques and that obtained from the Gaussian assumption. Here we develop a tighter bound for the decoy-state method, which yields a smaller failure probability. This improvement results in a higher key rate and increases the maximum distance over which secure key exchange is possible. By optimizing the system parameters, our simulation results show that our method almost closes the gap between the two previously proposed techniques and achieves a performance similar to that of conventional Gaussian approximations.

Unsupervised spike sorting based on discriminative subspace learning.

PubMed

Keshtkaran, Mohammad Reza; Yang, Zhi

2014-01-01

Spike sorting is a fundamental preprocessing step for many neuroscience studies which rely on the analysis of spike trains. In this paper, we present two unsupervised spike sorting algorithms based on discriminative subspace learning. The first algorithm simultaneously learns the discriminative feature subspace and performs clustering. It uses histogram of features in the most discriminative projection to detect the number of neurons. The second algorithm performs hierarchical divisive clustering that learns a discriminative 1-dimensional subspace for clustering in each level of the hierarchy until achieving almost unimodal distribution in the subspace. The algorithms are tested on synthetic and in-vivo data, and are compared against two widely used spike sorting methods. The comparative results demonstrate that our spike sorting methods can achieve substantially higher accuracy in lower dimensional feature space, and they are highly robust to noise. Moreover, they provide significantly better cluster separability in the learned subspace than in the subspace obtained by principal component analysis or wavelet transform.

Squeeze strengthening of magnetorheological fluids using mixed mode operation

NASA Astrophysics Data System (ADS)

Becnel, A. C.; Sherman, S. G.; Hu, W.; Wereley, N. M.

2015-05-01

This research details a novel method of increasing the shear yield stress of magnetorheological fluids by combining shear and squeeze modes of operation to manipulate particle chain structures, so-called squeeze strengthening. Using a custom built Searle cell magnetorheometer, which is a model device emulating a rotary magnetorheological energy absorber (MREA), the contribution of squeeze strengthening to the total controllable yield force is experimentally investigated. Using an eccentric rotating inner cylinder, characterization data from large (1 mm) and small (0.25 mm) nominal gap geometries are compared to investigate the squeeze strengthening effect. Details of the experimental setup and method are presented, and a hybrid model is used to explain experimental trends. This study demonstrates that it is feasible, utilizing squeeze strengthening to increase yield stress, to either (1) design a rotary MREA of a given volume to achieve higher energy absorption density (energy absorbed normalized by active fluid volume), or (2) reduce the volume of a given rotary MREA to achieve the same energy absorption density.

HO2 rovibrational eigenvalue studies for nonzero angular momentum

NASA Astrophysics Data System (ADS)

Wu, Xudong T.; Hayes, Edward F.

1997-08-01

An efficient parallel algorithm is reported for determining all bound rovibrational energy levels for the HO2 molecule for nonzero angular momentum values, J=1, 2, and 3. Performance tests on the CRAY T3D indicate that the algorithm scales almost linearly when up to 128 processors are used. Sustained performance levels of up to 3.8 Gflops have been achieved using 128 processors for J=3. The algorithm uses a direct product discrete variable representation (DVR) basis and the implicitly restarted Lanczos method (IRLM) of Sorensen to compute the eigenvalues of the polyatomic Hamiltonian. Since the IRLM is an iterative method, it does not require storage of the full Hamiltonian matrix—it only requires the multiplication of the Hamiltonian matrix by a vector. When the IRLM is combined with a formulation such as DVR, which produces a very sparse matrix, both memory and computation times can be reduced dramatically. This algorithm has the potential to achieve even higher performance levels for larger values of the total angular momentum.

Growth trajectories of mathematics achievement: Longitudinal tracking of student academic progress.

PubMed

Mok, Magdalena M C; McInerney, Dennis M; Zhu, Jinxin; Or, Anthony

2015-06-01

A number of methods to investigate growth have been reported in the literature, including hierarchical linear modelling (HLM), latent growth modelling (LGM), and multidimensional scaling applied to longitudinal profile analysis (LPAMS). This study aimed at modelling the mathematics growth of students over a span of 6 years from Grade 3 to Grade 9. The sample comprised secondary longitudinal data collected in three waves from n = 866 Hong Kong students when they were in Grade 3, Grade 6, and Grade 9. Mathematics achievement was measured thrice on a vertical scale linked with anchor items. Linear and nonlinear latent growth models were used to assess students' growth. Gender differences were also examined. A nonlinear latent growth curve with a decelerated rate had a good fit to the data. Initial achievement and growth rate were negatively correlated. No gender difference was found. Mathematics growth from Grade 6 to Grade 9 was slower than that from Grade 3 to Grade 6. Students with lower initial achievement improved at a faster rate than those who started at a higher level. Gender did not affect growth rate. © 2014 The British Psychological Society.

Differences in Achievement Motivation and Academic and Social Self-Concept in Gifted Students of Higher Education

ERIC Educational Resources Information Center

Sierra, María Dolores Valadez; Cuervo, Angel Alberto Valdés; Amezaga, Teodoro Rafael Wendlandt; Sánchez, Ana Carolina Reyes; Guzmán, Rogelio Zambrano; Agraz, Juan Pedro Navarro

2015-01-01

The purpose of this study is to identify groups of gifted university students that differ in their self-concept and achievement motivation. For this, 80 students who achieved scores of the 95th percentile or higher in the Raven's Progressive Matrices test were selected. Two groups were identified in terms of their social self-concept and the…

Study on validation method for femur finite element model under multiple loading conditions

NASA Astrophysics Data System (ADS)

Guan, Fengjiao; Zhang, Guanjun; Liu, Jie; Wang, Shujing; Luo, Xu

2018-03-01

Acquisition of accurate and reliable constitutive parameters related to bio-tissue materials was beneficial to improve biological fidelity of a Finite Element (FE) model and predict impact damages more effectively. In this paper, a femur FE model was established under multiple loading conditions with diverse impact positions. Then, based on sequential response surface method and genetic algorithms, the material parameters identification was transformed to a multi-response optimization problem. Finally, the simulation results successfully coincided with force-displacement curves obtained by numerous experiments. Thus, computational accuracy and efficiency of the entire inverse calculation process were enhanced. This method was able to effectively reduce the computation time in the inverse process of material parameters. Meanwhile, the material parameters obtained by the proposed method achieved higher accuracy.

Character recognition from trajectory by recurrent spiking neural networks.

PubMed

Jiangrong Shen; Kang Lin; Yueming Wang; Gang Pan

2017-07-01

Spiking neural networks are biologically plausible and power-efficient on neuromorphic hardware, while recurrent neural networks have been proven to be efficient on time series data. However, how to use the recurrent property to improve the performance of spiking neural networks is still a problem. This paper proposes a recurrent spiking neural network for character recognition using trajectories. In the network, a new encoding method is designed, in which varying time ranges of input streams are used in different recurrent layers. This is able to improve the generalization ability of our model compared with general encoding methods. The experiments are conducted on four groups of the character data set from University of Edinburgh. The results show that our method can achieve a higher average recognition accuracy than existing methods.

Associations between Children’s Intelligence and Academic Achievement: The Role of Sleep

PubMed Central

Erath, Stephen A.; Tu, Kelly M.; Buckhalt, Joseph A.; El-Sheikh, Mona

2015-01-01

Summary Sleep problems (long wake episodes, low sleep efficiency) were examined as moderators of the relation between children’s intelligence and academic achievement. The sample was comprised of 280 children (55% boys; 63% European Americans, 37% African Americans; M age = 10.40 years, SD = .65). Sleep was assessed through seven consecutive nights of actigraphy. Children’s performance on standardized tests of intelligence (Brief Intellectual Ability index of the Woodcock-Johnson III) and academic achievement (Alabama Reading and Math Test) were obtained. Age, sex, ethnicity, income-to-needs ratio, single parent status, zBMI, chronic illness, and pubertal development were controlled in analyses. Higher intelligence was strongly associated with higher academic achievement across a wide range of sleep quality. However, the association between intelligence and academic achievement was slightly attenuated among children with more long wake episodes or lower sleep efficiency compared to children with higher-quality sleep. PMID:25683475

Toy-playing behavior, sex-role orientation, spatial ability, and science achievement

NASA Astrophysics Data System (ADS)

Tracy, Dyanne M.

The purpose of this correlational study was to examine the possible relationships among children's extracurricular toy-playing habits, sex-role orientations, spatial abilities, and science achievement. Data were gathered from 282 midwestern, suburban, fifth-grade students. It was found that boys had significantly higher spatial skills than girls. No significant differences in spatial ability were found among students with different sex-role orientations. No significant differences in science achievement were found between girls and boys, or among students with the four different sex-role orientations. Students who had high spatial ability also had significantly higher science achievement scores than students with low spatial ability. Femininely oriented boys who reported low playing in the two-dimensional, gross-body-movement, and proportional-arrangement toy categories scored significantly higher on the test of science achievement than girls with the same sex-role and toy-playing behavior.

Associations between Dietary Intake and Academic Achievement in College Students: A Systematic Review

PubMed Central

2017-01-01

The impact of diet on academic achievement is a growing area of research. The aim of this systematic review was to evaluate the current evidence examining dietary intake and academic achievement in college/university students. Eight electronic databases were searched for studies published in English to January 2016. To be included, studies must have been conducted in higher education (i.e., college, university) students, reported measures of dietary intake and academic achievement, and reported the association between these. Data were extracted using a standardised tool, and studies were assessed for methodological quality. Seven studies were included, with four rated as positive quality, and the remaining three rated as neutral. Most studies were cross-sectional (n = 4), and conducted in America (n = 5). The most common dietary outcomes were fruit and vegetable (n = 3), and breakfast consumption (n = 3). Standardised grade point average (GPA) was the most common measure of academic achievement (n = 4). Five studies reported small to moderate significant positive associations between diet and academic achievement, including for breakfast, regular meal consumption, and meeting national recommendations for fruit intake. This review examines the current evidence regarding diet and academic achievement in college/university students. The results demonstrate that few studies exist in this population group. Future studies should consider the use of validated dietary assessment methods, comprehensive measures of overall diet, and use standardised assessment and reporting of academic outcomes. PMID:28946663

Associations between Dietary Intake and Academic Achievement in College Students: A Systematic Review.

PubMed

Burrows, Tracy L; Whatnall, Megan C; Patterson, Amanda J; Hutchesson, Melinda J

2017-09-25

The impact of diet on academic achievement is a growing area of research. The aim of this systematic review was to evaluate the current evidence examining dietary intake and academic achievement in college/university students. Eight electronic databases were searched for studies published in English to January 2016. To be included, studies must have been conducted in higher education (i.e., college, university) students, reported measures of dietary intake and academic achievement, and reported the association between these. Data were extracted using a standardised tool, and studies were assessed for methodological quality. Seven studies were included, with four rated as positive quality, and the remaining three rated as neutral. Most studies were cross-sectional ( n = 4), and conducted in America ( n = 5). The most common dietary outcomes were fruit and vegetable ( n = 3), and breakfast consumption ( n = 3). Standardised grade point average (GPA) was the most common measure of academic achievement ( n = 4). Five studies reported small to moderate significant positive associations between diet and academic achievement, including for breakfast, regular meal consumption, and meeting national recommendations for fruit intake. This review examines the current evidence regarding diet and academic achievement in college/university students. The results demonstrate that few studies exist in this population group. Future studies should consider the use of validated dietary assessment methods, comprehensive measures of overall diet, and use standardised assessment and reporting of academic outcomes.

Immobilization of Fab' fragments onto substrate surfaces: A survey of methods and applications.

PubMed

Crivianu-Gaita, Victor; Thompson, Michael

2015-08-15

Antibody immobilization onto surfaces has widespread applications in many different fields. It is desirable to bind antibodies such that their fragment-antigen-binding (Fab) units are oriented away from the surface in order to maximize analyte binding. The immobilization of only Fab' fragments yields benefits over the more traditional whole antibody immobilization technique. Bound Fab' fragments display higher surface densities, yielding a higher binding capacity for the analyte. The nucleophilic sulfide of the Fab' fragments allows for specific orientations to be achieved. For biosensors, this indicates a higher sensitivity and lower detection limit for a target analyte. The last thirty years have shown tremendous progress in the immobilization of Fab' fragments onto gold, Si-based, polysaccharide-based, plastic-based, magnetic, and inorganic surfaces. This review will show the current scope of Fab' immobilization techniques available and illustrate methods employed to minimize non-specific adsorption of undesirables. Furthermore, a variety of examples will be given to show the versatility of immobilized Fab' fragments in different applications and future directions of the field will be addressed, especially regarding biosensors. Copyright © 2015 Elsevier B.V. All rights reserved.

Compressed Symmetric Nested Arrays and Their Application for Direction-of-Arrival Estimation of Near-Field Sources.

PubMed

Li, Shuang; Xie, Dongfeng

2016-11-17

In this paper, a new sensor array geometry, called a compressed symmetric nested array (CSNA), is designed to increase the degrees of freedom in the near field. As its name suggests, a CSNA is constructed by getting rid of some elements from two identical nested arrays. The closed form expressions are also presented for the sensor locations and the largest degrees of freedom obtainable as a function of the total number of sensors. Furthermore, a novel DOA estimation method is proposed by utilizing the CSNA in the near field. By employing this new array geometry, our method can identify more sources than sensors. Compared with other existing methods, the proposed method achieves higher resolution because of increased array aperture. Simulation results are demonstrated to verify the effectiveness of the proposed method.

Realizing drug repositioning by adapting a recommendation system to handle the process.

PubMed

Ozsoy, Makbule Guclin; Özyer, Tansel; Polat, Faruk; Alhajj, Reda

2018-04-12

Drug repositioning is the process of identifying new targets for known drugs. It can be used to overcome problems associated with traditional drug discovery by adapting existing drugs to treat new discovered diseases. Thus, it may reduce associated risk, cost and time required to identify and verify new drugs. Nowadays, drug repositioning has received more attention from industry and academia. To tackle this problem, researchers have applied many different computational methods and have used various features of drugs and diseases. In this study, we contribute to the ongoing research efforts by combining multiple features, namely chemical structures, protein interactions and side-effects to predict new indications of target drugs. To achieve our target, we realize drug repositioning as a recommendation process and this leads to a new perspective in tackling the problem. The utilized recommendation method is based on Pareto dominance and collaborative filtering. It can also integrate multiple data-sources and multiple features. For the computation part, we applied several settings and we compared their performance. Evaluation results show that the proposed method can achieve more concentrated predictions with high precision, where nearly half of the predictions are true. Compared to other state of the art methods described in the literature, the proposed method is better at making right predictions by having higher precision. The reported results demonstrate the applicability and effectiveness of recommendation methods for drug repositioning.

Unique Normal Form and the Associated Coefficients for a Class of Three-Dimensional Nilpotent Vector Fields

NASA Astrophysics Data System (ADS)

Li, Jing; Kou, Liying; Wang, Duo; Zhang, Wei

2017-12-01

In this paper, we mainly focus on the unique normal form for a class of three-dimensional vector fields via the method of transformation with parameters. A general explicit recursive formula is derived to compute the higher order normal form and the associated coefficients, which can be achieved easily by symbolic calculations. To illustrate the efficiency of the approach, a comparison of our result with others is also presented.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Mills, G.J.; Brown, G.G.; Waterman, D.D.

The feasibility of prestressing commercial boron/epoxy and graphite/epoxy prepreg material to higher strengths and lower property dispersions is demonstrated. Its practical application as an on-line process for improving quality levels is possible with minor modifications to current experimental practice. The mechanics of the bendstressing method affects a controlled alteration in the fiber defect content to the extent that composite improvements can be achieved approaching the inherent fiber quality with dispersions in properties reduced to the 1 to 2% range. (Author, modified-PL)

Continuous-flow retro-Diels-Alder reaction: an efficient method for the preparation of pyrimidinone derivatives.

PubMed

Nekkaa, Imane; Palkó, Márta; Mándity, István M; Fülöp, Ferenc

2018-01-01

The syntheses of various pyrimidinones as potentially bioactive products by means of the highly controlled continuous-flow retro-Diels-Alder reaction of condensed pyrimidinone derivatives are presented. Noteworthy, the use of this approach allowed us to rapidly screen a selection of conditions and quickly confirm the viability of preparing the desired pyrimidinones in short reaction times. Yields typically higher than those published earlier using conventional batch or microwave processes were achieved.

SegAuth: A Segment-based Approach to Behavioral Biometric Authentication

PubMed Central

Li, Yanyan; Xie, Mengjun; Bian, Jiang

2016-01-01

Many studies have been conducted to apply behavioral biometric authentication on/with mobile devices and they have shown promising results. However, the concern about the verification accuracy of behavioral biometrics is still common given the dynamic nature of behavioral biometrics. In this paper, we address the accuracy concern from a new perspective—behavior segments, that is, segments of a gesture instead of the whole gesture as the basic building block for behavioral biometric authentication. With this unique perspective, we propose a new behavioral biometric authentication method called SegAuth, which can be applied to various gesture or motion based authentication scenarios. SegAuth can achieve high accuracy by focusing on each user’s distinctive gesture segments that frequently appear across his or her gestures. In SegAuth, a time series derived from a gesture/motion is first partitioned into segments and then transformed into a set of string tokens in which the tokens representing distinctive, repetitive segments are associated with higher genuine probabilities than those tokens that are common across users. An overall genuine score calculated from all the tokens derived from a gesture is used to determine the user’s authenticity. We have assessed the effectiveness of SegAuth using 4 different datasets. Our experimental results demonstrate that SegAuth can achieve higher accuracy consistently than existing popular methods on the evaluation datasets. PMID:28573214

SegAuth: A Segment-based Approach to Behavioral Biometric Authentication.

PubMed

Li, Yanyan; Xie, Mengjun; Bian, Jiang

2016-10-01

Many studies have been conducted to apply behavioral biometric authentication on/with mobile devices and they have shown promising results. However, the concern about the verification accuracy of behavioral biometrics is still common given the dynamic nature of behavioral biometrics. In this paper, we address the accuracy concern from a new perspective-behavior segments, that is, segments of a gesture instead of the whole gesture as the basic building block for behavioral biometric authentication. With this unique perspective, we propose a new behavioral biometric authentication method called SegAuth, which can be applied to various gesture or motion based authentication scenarios. SegAuth can achieve high accuracy by focusing on each user's distinctive gesture segments that frequently appear across his or her gestures. In SegAuth, a time series derived from a gesture/motion is first partitioned into segments and then transformed into a set of string tokens in which the tokens representing distinctive, repetitive segments are associated with higher genuine probabilities than those tokens that are common across users. An overall genuine score calculated from all the tokens derived from a gesture is used to determine the user's authenticity. We have assessed the effectiveness of SegAuth using 4 different datasets. Our experimental results demonstrate that SegAuth can achieve higher accuracy consistently than existing popular methods on the evaluation datasets.

De novo peptide sequencing by deep learning

PubMed Central

Tran, Ngoc Hieu; Zhang, Xianglilan; Xin, Lei; Shan, Baozhen; Li, Ming

2017-01-01

De novo peptide sequencing from tandem MS data is the key technology in proteomics for the characterization of proteins, especially for new sequences, such as mAbs. In this study, we propose a deep neural network model, DeepNovo, for de novo peptide sequencing. DeepNovo architecture combines recent advances in convolutional neural networks and recurrent neural networks to learn features of tandem mass spectra, fragment ions, and sequence patterns of peptides. The networks are further integrated with local dynamic programming to solve the complex optimization task of de novo sequencing. We evaluated the method on a wide variety of species and found that DeepNovo considerably outperformed state of the art methods, achieving 7.7–22.9% higher accuracy at the amino acid level and 38.1–64.0% higher accuracy at the peptide level. We further used DeepNovo to automatically reconstruct the complete sequences of antibody light and heavy chains of mouse, achieving 97.5–100% coverage and 97.2–99.5% accuracy, without assisting databases. Moreover, DeepNovo is retrainable to adapt to any sources of data and provides a complete end-to-end training and prediction solution to the de novo sequencing problem. Not only does our study extend the deep learning revolution to a new field, but it also shows an innovative approach in solving optimization problems by using deep learning and dynamic programming. PMID:28720701

Stable current outputs and phytate degradation by yeast-based biofuel cell.

PubMed

Hubenova, Yolina; Georgiev, Danail; Mitov, Mario

2014-09-01

In this paper, we report for the first time that Candida melibiosica 2491 yeast strain expresses enhanced phytase activity when used as a biocatalyst in biofuel cells. The polarization also results in an increase of the yeast biomass. Higher steady-state electrical outputs, assigned to earlier production of an endogenous mediator, were achieved at continuous polarization under constant load. The obtained results prove that the C. melibiosica yeast-based biofuel cell could be used for simultaneous electricity generation and phytate bioremediation. In addition, the higher phytase activity obtained by interruptive polarization suggests a new method for increasing the phytase yield from microorganisms. Copyright © 2014 John Wiley & Sons, Ltd.

[Hip resurfacing arthroplasty].

PubMed

Witzleb, W-C; Knecht, A; Beichler, T; Köhler, T; Günther, K-P

2004-11-01

In comparison to stemmed total hip replacements, hip resurfacing offers advantages especially in joint stability and amount of femoral bone resection. After the poor results achieved with this concept that were mainly caused by failure of the materials used, reintroduction of the metal-on-metal bearing initiated a renaissance. This bearing, the cementless cup, and the improved surgical technique led to better short- to medium-term results. Revision and complication rates are now comparable to conventional total hip replacements. The functional capacity of the method is higher. Because long-term results are not available, however, questions remain, for instance, the consequences of the higher metal ion serum concentrations or the impossibility of changing the inlay when femoral revision becomes necessary.

Predictors of no-scalpel vasectomy acceptance in Karimnagar district, Andhra Pradesh.

PubMed

Valsangkar, Sameer; Sai, Surendranath K; Bele, Samir D; Bodhare, Trupti N

2012-07-01

Karimnagar District has consistently achieved highest rates of no-scalpel vasectomy (NSV) in the past decade when compared to state and national rates. This study was conducted to elucidate the underlying causes for higher acceptance of NSV in the district. A community-based, case control study was conducted. Sampling techniques used were purposive and simple random sampling. A semi-structured questionnaire was used to evaluate the socio-demographic, family characteristics, contraceptive history and predictors of contraceptive choice in 116 NSV acceptors and 120 other contraceptive users (OCUs). Postoperative complications and experiences were ascertained in NSV acceptors. Age (χ(2)=11.79, P value = 0.008), literacy (χ(2)=17.95, P value = 0.03), duration of marriage (χ(2)=14.23, P value = 0.008) and number of children (χ(2)=10.45, P value = 0.01) were significant for acceptance of NSV. Among the predictors, method suggested by peer/ health worker (OR = 1.5, P value = 0.01), method does not require regular intervention (OR = 1.3, P value = 0.004) and permanence of the method (OR = 1.2, P value = 0.031) were significant. Acceptors were most satisfied with the shorter duration required to return to work and the most common complication was persistent postoperative pain among 12 (10.34%) of the acceptors. Advocating and implementing family planning is of high significance in view of the population growth in India and drawing from the demographic profile, predictors, pool of trainers and experiences in Karimnagar District, a similar achievement of higher rates of this simple procedure with few complications can be replicated.

Women's participation in household decision-making and higher dietary diversity: findings from nationally representative data from Ghana.

PubMed

Amugsi, Dickson A; Lartey, Anna; Kimani, Elizabeth; Mberu, Blessing U

2016-05-31

Low-quality monotonous diet is a major problem confronting resource-constrained settings across the world. Starchy staple foods dominate the diets in these settings. This places the population, especially women of reproductive age, at a risk of micronutrients deficiencies. This study seeks to examine the association between women's decision-making autonomy and women's achievement of higher dietary diversity (DD) and determine the socio-demographic factors that can independently predict women's attainment of higher DD. The study used data from the 2008 Ghana Demographic and Health Survey. The participants comprised of 2262 women aged 15-49 years and who have complete dietary data. The DD score was derived from a 24-h recall of intake of foods from nine groups. The score was dichotomized into lower DD (DD ≤4) and higher (DD ≥5). Logistic regression was used to assess the association between women decision-making autonomy (final say on how to spend money, making household purchases, own health care, opinions on wife-beating, and sexual intercourse with husband) and the achievement of higher DD. The logistic regression models were adjusted for covariates at the individual and household levels. The analysis showed that women participation in decision-making regarding household purchases was significantly associated with higher DD, after adjusting for individual and household level covariates. The odds of achieving higher DD were higher among women who had a say in deciding household purchases, compared to women who did not have a say (OR = 1.74, 95 % CI = 1.24, 2.42). Women who had more than primary education were 1.6 times more likely to achieve higher DD, compared to those with no education (95 % CI = 1.12, 2.20). Compared to women who lived in polygamous households, those who lived in monogamous households had higher odds of achieving higher DD (OR = 1.42, 95 % CI = 1.04, 1.93). Net other covariates, women who have a say in making household purchases are more likely to achieve higher DD compare to those who do not have a say. This may indicate autonomy to buy nutritious foods, suggesting that improving women decision-making autonomy could have a positive impact on women dietary intake.

GPUs benchmarking in subpixel image registration algorithm

NASA Astrophysics Data System (ADS)

Sanz-Sabater, Martin; Picazo-Bueno, Jose Angel; Micó, Vicente; Ferrerira, Carlos; Granero, Luis; Garcia, Javier

2015-05-01

Image registration techniques are used among different scientific fields, like medical imaging or optical metrology. The straightest way to calculate shifting between two images is using the cross correlation, taking the highest value of this correlation image. Shifting resolution is given in whole pixels which cannot be enough for certain applications. Better results can be achieved interpolating both images, as much as the desired resolution we want to get, and applying the same technique described before, but the memory needed by the system is significantly higher. To avoid memory consuming we are implementing a subpixel shifting method based on FFT. With the original images, subpixel shifting can be achieved multiplying its discrete Fourier transform by a linear phase with different slopes. This method is high time consuming method because checking a concrete shifting means new calculations. The algorithm, highly parallelizable, is very suitable for high performance computing systems. GPU (Graphics Processing Unit) accelerated computing became very popular more than ten years ago because they have hundreds of computational cores in a reasonable cheap card. In our case, we are going to register the shifting between two images, doing the first approach by FFT based correlation, and later doing the subpixel approach using the technique described before. We consider it as `brute force' method. So we will present a benchmark of the algorithm consisting on a first approach (pixel resolution) and then do subpixel resolution approaching, decreasing the shifting step in every loop achieving a high resolution in few steps. This program will be executed in three different computers. At the end, we will present the results of the computation, with different kind of CPUs and GPUs, checking the accuracy of the method, and the time consumed in each computer, discussing the advantages, disadvantages of the use of GPUs.

A novel fast gas chromatography method for higher time resolution measurements of speciated monoterpenes in air

NASA Astrophysics Data System (ADS)

Jones, C. E.; Kato, S.; Nakashima, Y.; Kajii, Y.

2014-05-01

Biogenic emissions supply the largest fraction of non-methane volatile organic compounds (VOC) from the biosphere to the atmospheric boundary layer, and typically comprise a complex mixture of reactive terpenes. Due to this chemical complexity, achieving comprehensive measurements of biogenic VOC (BVOC) in air within a satisfactory time resolution is analytically challenging. To address this, we have developed a novel, fully automated Fast Gas Chromatography (Fast-GC) based technique to provide higher time resolution monitoring of monoterpenes (and selected other C9-C15 terpenes) during plant emission studies and in ambient air. To our knowledge, this is the first study to apply a Fast-GC based separation technique to achieve quantification of terpenes in ambient air. Three chromatography methods have been developed for atmospheric terpene analysis under different sampling scenarios. Each method facilitates chromatographic separation of selected BVOC within a significantly reduced analysis time compared to conventional GC methods, whilst maintaining the ability to quantify individual monoterpene structural isomers. Using this approach, the C9-C15 BVOC composition of single plant emissions may be characterised within a 14.5 min analysis time. Moreover, in-situ quantification of 12 monoterpenes in unpolluted ambient air may be achieved within an 11.7 min chromatographic separation time (increasing to 19.7 min when simultaneous quantification of multiple oxygenated C9-C10 terpenoids is required, and/or when concentrations of anthropogenic VOC are significant). These analysis times potentially allow for a twofold to fivefold increase in measurement frequency compared to conventional GC methods. Here we outline the technical details and analytical capability of this chromatographic approach, and present the first in-situ Fast-GC observations of 6 monoterpenes and the oxygenated BVOC (OBVOC) linalool in ambient air. During this field deployment within a suburban forest ~30 km west of central Tokyo, Japan, the Fast-GC limit of detection with respect to monoterpenes was 4-5 ppt, and the agreement between Fast-GC and PTR-MS derived total monoterpene mixing ratios was consistent with previous GC/PTR-MS comparisons. The measurement uncertainties associated with the Fast-GC quantification of monoterpenes are ≤ 12%, while larger uncertainties (up to ~25%) are associated with the OBVOC and sesquiterpene measurements.

Localizing New Pulsars with Intensity Mapping

NASA Astrophysics Data System (ADS)

Swiggum, Joe; Gentile, Peter

2018-01-01

Although low-frequency, single dish pulsar surveys provide an efficient means of searching large regions of sky quickly, the localization of new discoveries is poor. For example, discoveries from 350 MHz surveys using the Green Bank Telescope (GBT) have position uncertainties up to the FWHM of the telescope's "beam" on the sky, over half a degree! Before finding a coherent timing solution (requires 8-12 months of dedicated timing observations) a "gridding" method is usually employed to improve localization of new pulsars, whereby a grid of higher frequency beam positions is used to tile the initial error region. This method often requires over an hour of observing time to achieve arcminute-precision localization (provided the pulsar is detectable at higher frequencies).Here, we describe another method that uses the same observing frequency as the discovery observation and scans over Right Ascension and Declination directions around the nominal position. A Gaussian beam model is fit to folded pulse profile intensities as a function of time/position to provide improved localization. Using five test cases, we show that intensity mapping localization at 350 MHz with the GBT yields pulsar positions to 1 arcminute precision, facilitating high-frequency follow-up and higher significance detections for future pulsar timing. This method is also well suited to be directly implemented in future low-frequency drift scan pulsar surveys (e.g. with the Five hundred meter Aperture Spherical Telescope; FAST).

Prostate-Specific Antigen Persistence After Radical Prostatectomy as a Predictive Factor of Clinical Relapse-Free Survival and Overall Survival: 10-Year Data of the ARO 96-02 Trial

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wiegel, Thomas, E-mail: thomas.wiegel@uniklinik-ulm.de; Bartkowiak, Detlef; Bottke, Dirk

2015-02-01

Objective: The ARO 96-02 trial primarily compared wait-and-see (WS, arm A) with adjuvant radiation therapy (ART, arm B) in prostate cancer patients who achieved an undetectable prostate-specific antigen (PSA) after radical prostatectomy (RP). Here, we report the outcome with up to 12 years of follow-up of patients who retained a post-RP detectable PSA and received salvage radiation therapy (SRT, arm C). Methods and Materials: For the study, 388 patients with pT3-4pN0 prostate cancer with positive or negative surgical margins were recruited. After RP, 307 men achieved an undetectable PSA (arms A + B). In 78 patients the PSA remained above thresholds (median 0.6,more » range 0.05-5.6 ng/mL). Of the latter, 74 consented to receive 66 Gy to the prostate bed, and SRT was applied at a median of 86 days after RP. Clinical relapse-free survival, metastasis-free survival, and overall survival were determined by the Kaplan-Meier method. Results: Patients with persisting PSA after RP had higher preoperative PSA values, higher tumor stages, higher Gleason scores, and more positive surgical margins than did patients in arms A + B. For the 74 patients, the 10-year clinical relapse-free survival rate was 63%. Forty-three men had hormone therapy; 12 experienced distant metastases; 23 patients died. Compared with men who did achieve an undetectable PSA, the arm-C patients fared significantly worse, with a 10-year metastasis-free survival of 67% versus 83% and overall survival of 68% versus 84%, respectively. In Cox regression analysis, Gleason score ≥8 (hazard ratio [HR] 2.8), pT ≥ 3c (HR 2.4), and extraprostatic extension ≥2 mm (HR 3.6) were unfavorable risk factors of progression. Conclusions: A persisting PSA after prostatectomy seems to be an important prognosticator of clinical progression for pT3 tumors. It correlates with a higher rate of distant metastases and with worse overall survival. A larger prospective study is required to determine which patient subgroups will benefit most from which treatment option.« less

A plasma arc reactor for fullerene research

NASA Astrophysics Data System (ADS)

Anderson, T. T.; Dyer, P. L.; Dykes, J. W.; Klavins, P.; Anderson, P. E.; Liu, J. Z.; Shelton, R. N.

1994-12-01

A modified Krätschmer-Huffman reactor for the mass production of fullerenes is presented. Fullerene mass production is fundamental for the synthesis of higher and endohedral fullerenes. The reactor employs mechanisms for continuous graphite-rod feeding and in situ slag removal. Soot collects into a Soxhlet extraction thimble which serves as a fore-line vacuum pump filter, thereby easing fullerene separation from soot. Thermal gravimetric analysis (TGA) for yield determination is reported. This TGA method is faster and uses smaller samples than Soxhlet extraction methods which rely on aromatic solvents. Production of 10 g of soot per hour is readily achieved utilizing this reactor. Fullerene yields of 20% are attained routinely.

Protein annotation from protein interaction networks and Gene Ontology.

PubMed

Nguyen, Cao D; Gardiner, Katheleen J; Cios, Krzysztof J

2011-10-01

We introduce a novel method for annotating protein function that combines Naïve Bayes and association rules, and takes advantage of the underlying topology in protein interaction networks and the structure of graphs in the Gene Ontology. We apply our method to proteins from the Human Protein Reference Database (HPRD) and show that, in comparison with other approaches, it predicts protein functions with significantly higher recall with no loss of precision. Specifically, it achieves 51% precision and 60% recall versus 45% and 26% for Majority and 24% and 61% for χ²-statistics, respectively. Copyright © 2011 Elsevier Inc. All rights reserved.

Structured catalyst bed and method for conversion of feed materials to chemical products and liquid fuels

DOEpatents

Wang, Yong , Liu; Wei, [Richland, WA

2012-01-24

The present invention is a structured monolith reactor and method that provides for controlled Fischer-Tropsch (FT) synthesis. The invention controls mass transport limitations leading to higher CO conversion and lower methane selectivity. Over 95 wt % of the total product liquid hydrocarbons obtained from the monolithic catalyst are in the carbon range of C.sub.5-C.sub.18. The reactor controls readsorption of olefins leading to desired products with a preselected chain length distribution and enhanced overall reaction rate. And, liquid product analysis shows readsorption of olefins is reduced, achieving a narrower FT product distribution.

GaAs-based resonant tunneling diode (RTD) epitaxy on Si for highly sensitive strain gauge applications.

PubMed

Li, Jie; Guo, Hao; Liu, Jun; Tang, Jun; Ni, Haiqiao; Shi, Yunbo; Xue, Chenyang; Niu, Zhichuan; Zhang, Wendong; Li, Mifeng; Yu, Ying

2013-05-08

As a highly sensitive strain gauge element, GaAs-based resonant tunneling diode (RTD) has already been applied in microelectromechanical system (MEMS) sensors. Due to poor mechanical properties and high cost, GaAs-based material has been limited in applications as the substrate for MEMS. In this work, we present a method to fabricate the GaAs-based RTD on Si substrate. From the experimental results, it can be concluded that the piezoresistive coefficient achieved with this method reached 3.42 × 10-9 m2/N, which is about an order of magnitude higher than the Si-based semiconductor piezoresistors.

A pruning algorithm for Meta-blocking based on cumulative weight

NASA Astrophysics Data System (ADS)

Zhang, Fulin; Gao, Zhipeng; Niu, Kun

2017-08-01

Entity Resolution is an important process in data cleaning and data integration. It usually employs a blocking method to avoid the quadratic complexity work when scales to large data sets. Meta-blocking can perform better in the context of highly heterogeneous information spaces. Yet, its precision and efficiency still have room to improve. In this paper, we present a new pruning algorithm for Meta-Blocking. It can achieve a higher precision than the existing WEP algorithm at a small cost of recall. In addition, can reduce the runtime of the blocking process. We evaluate our proposed method over five real-world data sets.

Jumping-Droplet-Enhanced Condensation on Scalable Superhydrophobic Nanostructured Surfaces

DOE Office of Scientific and Technical Information (OSTI.GOV)

Miljkovic, N; Enright, R; Nam, Y

When droplets coalesce on a superhydrophobic nanostructured surface, the resulting droplet can jump from the surface due to the release of excess surface energy. If designed properly, these superhydrophobic nanostructured surfaces can not only allow for easy droplet removal at micrometric length scales during condensation but also promise to enhance heat transfer performance. However, the rationale for the design of an ideal nanostructured surface as well as heat transfer experiments demonstrating the advantage of this jumping behavior are lacking. Here, we show that silanized copper oxide surfaces created via a simple fabrication method can achieve highly efficient jumping-droplet condensation heatmore » transfer. We experimentally demonstrated a 25% higher overall heat flux and 30% higher condensation heat transfer coefficient compared to state-of-the-art hydrophobic condensing surfaces at low supersaturations (<1.12). This work not only shows significant condensation heat transfer enhancement but also promises a low cost and scalable approach to increase efficiency for applications such as atmospheric water harvesting and dehumidification. Furthermore, the results offer insights and an avenue to achieve high flux superhydrophobic condensation.« less

Processing and properties of magnesium containing a dense uniform dispersion of nanoparticles.

PubMed

Chen, Lian-Yi; Xu, Jia-Quan; Choi, Hongseok; Pozuelo, Marta; Ma, Xiaolong; Bhowmick, Sanjit; Yang, Jenn-Ming; Mathaudhu, Suveen; Li, Xiao-Chun

2015-12-24

Magnesium is a light metal, with a density two-thirds that of aluminium, is abundant on Earth and is biocompatible; it thus has the potential to improve energy efficiency and system performance in aerospace, automobile, defence, mobile electronics and biomedical applications. However, conventional synthesis and processing methods (alloying and thermomechanical processing) have reached certain limits in further improving the properties of magnesium and other metals. Ceramic particles have been introduced into metal matrices to improve the strength of the metals, but unfortunately, ceramic microparticles severely degrade the plasticity and machinability of metals, and nanoparticles, although they have the potential to improve strength while maintaining or even improving the plasticity of metals, are difficult to disperse uniformly in metal matrices. Here we show that a dense uniform dispersion of silicon carbide nanoparticles (14 per cent by volume) in magnesium can be achieved through a nanoparticle self-stabilization mechanism in molten metal. An enhancement of strength, stiffness, plasticity and high-temperature stability is simultaneously achieved, delivering a higher specific yield strength and higher specific modulus than almost all structural metals.

Exceptional high fatigue strength in Cu-15at.%Al alloy with moderate grain size

PubMed Central

Liu, Rui; Tian, Yanzhong; Zhang, Zhenjun; An, Xianghai; Zhang, Peng; Zhang, Zhefeng

2016-01-01

It is commonly proposed that the fatigue strength can be enhanced by increasing the tensile strength, but this conclusion needs to be reconsidered according to our study. Here a recrystallized α-Cu-15at.%Al alloy with moderate grain size of 0.62 μm was fabricated by cold rolling and annealing, and this alloy achieved exceptional high fatigue strength of 280 MPa at 107 cycles. This value is much higher than the fatigue strength of 200 MPa for the nano-crystalline counterpart (0.04 μm in grain size) despite its higher tensile strength. The remarkable improvement of fatigue strength should be mainly attributed to the microstructure optimization, which helps achieve the reduction of initial damage and the dispersion of accumulated damage. A new strategy of “damage reduction” was then proposed for fatigue strength improvement, to supplement the former strengthening principle. The methods and strategies summarized in this work offer a general pathway for further improvement of fatigue strength, in order to ensure the long-term safety of structural materials. PMID:27264347

Lamb mode selection for accurate wall loss estimation via guided wave tomography

NASA Astrophysics Data System (ADS)

Huthwaite, P.; Ribichini, R.; Lowe, M. J. S.; Cawley, P.

2014-02-01

Guided wave tomography offers a method to accurately quantify wall thickness losses in pipes and vessels caused by corrosion. This is achieved using ultrasonic waves transmitted over distances of approximately 1-2m, which are measured by an array of transducers and then used to reconstruct a map of wall thickness throughout the inspected region. To achieve accurate estimations of remnant wall thickness, it is vital that a suitable Lamb mode is chosen. This paper presents a detailed evaluation of the fundamental modes, S0 and A0, which are of primary interest in guided wave tomography thickness estimates since the higher order modes do not exist at all thicknesses, to compare their performance using both numerical and experimental data while considering a range of challenging phenomena. The sensitivity of A0 to thickness variations was shown to be superior to S0, however, the attenuation from A0 when a liquid loading was present was much higher than S0. A0 was less sensitive to the presence of coatings on the surface of than S0.

Effective Identification of Similar Patients Through Sequential Matching over ICD Code Embedding.

PubMed

Nguyen, Dang; Luo, Wei; Venkatesh, Svetha; Phung, Dinh

2018-04-11

Evidence-based medicine often involves the identification of patients with similar conditions, which are often captured in ICD (International Classification of Diseases (World Health Organization 2013)) code sequences. With no satisfying prior solutions for matching ICD-10 code sequences, this paper presents a method which effectively captures the clinical similarity among routine patients who have multiple comorbidities and complex care needs. Our method leverages the recent progress in representation learning of individual ICD-10 codes, and it explicitly uses the sequential order of codes for matching. Empirical evaluation on a state-wide cancer data collection shows that our proposed method achieves significantly higher matching performance compared with state-of-the-art methods ignoring the sequential order. Our method better identifies similar patients in a number of clinical outcomes including readmission and mortality outlook. Although this paper focuses on ICD-10 diagnosis code sequences, our method can be adapted to work with other codified sequence data.

Regional Principal Color Based Saliency Detection

PubMed Central

Lou, Jing; Ren, Mingwu; Wang, Huan

2014-01-01

Saliency detection is widely used in many visual applications like image segmentation, object recognition and classification. In this paper, we will introduce a new method to detect salient objects in natural images. The approach is based on a regional principal color contrast modal, which incorporates low-level and medium-level visual cues. The method allows a simple computation of color features and two categories of spatial relationships to a saliency map, achieving higher F-measure rates. At the same time, we present an interpolation approach to evaluate resulting curves, and analyze parameters selection. Our method enables the effective computation of arbitrary resolution images. Experimental results on a saliency database show that our approach produces high quality saliency maps and performs favorably against ten saliency detection algorithms. PMID:25379960

Effect of Pulse Parameters on Weld Quality in Pulsed Gas Metal Arc Welding: A Review

NASA Astrophysics Data System (ADS)

Pal, Kamal; Pal, Surjya K.

2011-08-01

The weld quality comprises bead geometry and its microstructure, which influence the mechanical properties of the weld. The coarse-grained weld microstructure, higher heat-affected zone, and lower penetration together with higher reinforcement reduce the weld service life in continuous mode gas metal arc welding (GMAW). Pulsed GMAW (P-GMAW) is an alternative method providing a better way for overcoming these afore mentioned problems. It uses a higher peak current to allow one molten droplet per pulse, and a lower background current to maintain the arc stability. Current pulsing refines the grains in weld fusion zone with increasing depth of penetration due to arc oscillations. Optimum weld joint characteristics can be achieved by controlling the pulse parameters. The process is versatile and easily automated. This brief review illustrates the effect of pulse parameters on weld quality.

Electron acceleration by a tightly focused Hermite-Gaussian beam: higher-order corrections

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zhao Zhiguo; Institute of Laser Physics and Chemistry, Sichuan University, Chengdu 610064; Yang Dangxiao

2008-03-15

Taking the TEM{sub 1,0}-mode Hermite-Gaussian (H-G) beam as a numerical calculation example, and based on the method of the perturbation series expansion, the higher-order field corrections of H-G beams are derived and used to study the electron acceleration by a tightly focused H-G beam in vacuum. For the case of the off-axis injection the field corrections to the terms of order f{sup 3} (f=1/kw{sub 0}, k and w{sub 0} being the wavenumber and waist width, respectively) are considered, and for the case of the on-axis injection the contributions of the terms of higher orders are negligible. By a suitable optimizationmore » of injection parameters the energy gain in the giga-electron-volt regime can be achieved.« less

The effect of technology on student science achievement

NASA Astrophysics Data System (ADS)

Hilton, June Kraft

2003-10-01

Prior research indicates that technology has had little effect on raising student achievement. Little empirical research exists, however, studying the effects of technology as a tool to improve student achievement through development of higher order thinking skills. Also, prior studies have not focused on the manner in which technology is being used in the classroom and at home to enhance teaching and learning. Empirical data from a secondary school representative of those in California were analyzed to determine the effects of technology on student science achievement. The quantitative analysis methods for the school data study included a multiple linear path analysis, using final course grade as the ultimate exogenous variable. In addition, empirical data from a nationwide survey on how Americans use the Internet were disaggregated by age and analyzed to determine the relationships between computer and Internet experience and (a) Internet use at home for school assignments and (b) more general computer use at home for school assignments for school age children. Analysis of data collected from the a "A Nation Online" Survey conducted by the United States Census Bureau assessed these relationships via correlations and cross-tabulations. Finally, results from these data analyses were assessed in conjunction with systemic reform efforts from 12 states designed to address improvements in science and mathematics education in light of the Third International Mathematics and Science Survey (TIMSS). Examination of the technology efforts in those states provided a more nuanced understanding of the impact technology has on student achievement. Key findings included evidence that technology training for teachers increased their use of the computer for instruction but students' final science course grade did not improve; school age children across the country did not use the computer at home for such higher-order cognitive activities as graphics and design or spreadsheets/databases; and states whose systemic reform initiatives included a mix of capacity building and alignment to state standards realized improved student achievement on the 2000 NAEP Science Assessment.

Effect of delayed-release dimethyl fumarate on no evidence of disease activity in relapsing-remitting multiple sclerosis: integrated analysis of the phase III DEFINE and CONFIRM studies.

PubMed

Havrdova, E; Giovannoni, G; Gold, R; Fox, R J; Kappos, L; Phillips, J Theodore; Okwuokenye, M; Marantz, J L

2017-05-01

Significant effects on clinical/neuroradiological disease activity have been reported in patients with relapsing-remitting multiple sclerosis treated with delayed-release dimethyl fumarate (DMF) in phase III DEFINE/CONFIRM trials. We conducted a post hoc analysis of integrated data from DEFINE/CONFIRM to evaluate the effect of DMF on achieving no evidence of disease activity (NEDA) in patients with relapsing-remitting multiple sclerosis. The analysis included patients randomized to DMF 240 mg twice daily, placebo or glatiramer acetate (CONFIRM only) for ≤2 years. A time-to-event method was used to estimate the percentage of patients achieving NEDA. Clinical NEDA (no relapses/no 12-week confirmed disability progression) was analysed in the intention-to-treat (ITT) population. Neuroradiological (no new/newly enlarging T2 hyperintense lesions/no gadolinium-enhancing lesions) and overall NEDA (clinical and neuroradiological NEDA) were analysed in the magnetic resonance imaging (MRI) cohort. The ITT and MRI populations comprised 1540 and 692 patients, respectively. The percentage of patients with clinical NEDA (ITT population) and neuroradiological NEDA (MRI cohort) was higher with DMF versus placebo over 2 years [clinical NEDA: 38.9% relative reduction; hazard ratio (HR), 0.61; 95% confidence interval (CI), 0.52-0.72; P < 0.0001; neuroradiological NEDA: 40.0% relative reduction; HR, 0.60; 95% CI, 0.49-0.73; P < 0.0001]. The percentage of patients achieving overall NEDA (MRI cohort) was also higher with DMF (26%) versus placebo (12%) over 2 years, with a relative risk reduction of 42.7% (HR, 0.57; 95% CI, 0.48-0.69; P < 0.0001). A significantly higher percentage of patients treated with DMF achieved NEDA status over 2 years compared with placebo. © 2017 Biogen. European Journal of Neurology published by John Wiley & Sons Ltd on behalf of European Academy of Neurology.

Underground Mining Method Selection Using WPM and PROMETHEE

NASA Astrophysics Data System (ADS)

Balusa, Bhanu Chander; Singam, Jayanthu

2018-04-01

The aim of this paper is to represent the solution to the problem of selecting suitable underground mining method for the mining industry. It is achieved by using two multi-attribute decision making techniques. These two techniques are weighted product method (WPM) and preference ranking organization method for enrichment evaluation (PROMETHEE). In this paper, analytic hierarchy process is used for weight's calculation of the attributes (i.e. parameters which are used in this paper). Mining method selection depends on physical parameters, mechanical parameters, economical parameters and technical parameters. WPM and PROMETHEE techniques have the ability to consider the relationship between the parameters and mining methods. The proposed techniques give higher accuracy and faster computation capability when compared with other decision making techniques. The proposed techniques are presented to determine the effective mining method for bauxite mine. The results of these techniques are compared with methods used in the earlier research works. The results show, conventional cut and fill method is the most suitable mining method.

High Energy, Long Cycle Life Lithium-ion Batteries for PHEV Application

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wang, Donghai; Manthiram, Arumugam; Wang, Chao-Yang

High-loading and high quality PSU Si anode has been optimized and fabricated. The electrochemical performance has been utilized. The PSU Si-graphite anode exhibits the mass loading of 5.8 mg/cm2, charge capacity of 850 mAh/ g and good cycling performance. This optimized electrode has been used for full-cell fabrication. The performance enhancement of Ni-rich materials can be achieved by a diversity of strategies. Higher Mn content and a small amount of Al doping can improve the electrochemical performance by suppressing interfacial side reactions with electrolytes, thus greatly benefiting the cyclability of the samples. Also, surface coatings of Li-rich materials and AlFmore » 3 are able to improve the performance stability of Ni-rich cathodes. One kilogram of optimized concentration-gradient LiNi 0.76Co 0.10Mn 0.14O 2 (CG) with careful control of composition, morphology and electrochemical performance was delivered to our collaborators. The sample achieved an initial specific capacity close to 190 mA h g -1 at C/10 rate and 180 mA h g -1 at C/3 rate as well as good cyclability in pouch full cells with a 4.4 V upper cut-off voltage at room temperature. Electrolyte additive with Si-N skeleton forms a less resistant SEI on the surface of silicon anode (from PSU) as evidenced by the evolution of the impedance at various lithiation/de-lithiation stages and the cycling data The prelithiation result demonstrates a solution processing method to achieve large area, uniform SLMP coating on well-made anode surface for the prelithiation of lithium-ion batteries. The prelithiation effect with this method is applied both in graphite half cells, graphite/NMC full cells, SiO half cells, SiO/NMC full cells, Si-Graphite half cells and Si-Graphite/NMC full cells with improvements in cycle performance and higher first cycle coulombic efficiency than their corresponding cells without SLMP prelithiation. As to the full cell fabrication and test, full pouch cells with high capacity of 2.2 Ah and 1.2 Ah have been fabricated and delivered. The cells show great uniformity and good cycling performance. The prelithiation method effectively compensate the loss in the first cycle. The cell with high energy density and long-cycle life has been achieved.« less

Computer-aided interpretation approach for optical tomographic images

NASA Astrophysics Data System (ADS)

Klose, Christian D.; Klose, Alexander D.; Netz, Uwe J.; Scheel, Alexander K.; Beuthan, Jürgen; Hielscher, Andreas H.

2010-11-01

A computer-aided interpretation approach is proposed to detect rheumatic arthritis (RA) in human finger joints using optical tomographic images. The image interpretation method employs a classification algorithm that makes use of a so-called self-organizing mapping scheme to classify fingers as either affected or unaffected by RA. Unlike in previous studies, this allows for combining multiple image features, such as minimum and maximum values of the absorption coefficient for identifying affected and not affected joints. Classification performances obtained by the proposed method were evaluated in terms of sensitivity, specificity, Youden index, and mutual information. Different methods (i.e., clinical diagnostics, ultrasound imaging, magnet resonance imaging, and inspection of optical tomographic images), were used to produce ground truth benchmarks to determine the performance of image interpretations. Using data from 100 finger joints, findings suggest that some parameter combinations lead to higher sensitivities, while others to higher specificities when compared to single parameter classifications employed in previous studies. Maximum performances are reached when combining the minimum/maximum ratio of the absorption coefficient and image variance. In this case, sensitivities and specificities over 0.9 can be achieved. These values are much higher than values obtained when only single parameter classifications were used, where sensitivities and specificities remained well below 0.8.

Do resource utilization and clinical measures still vary across dialysis chains after controlling for the local practices of facilities and physicians?

PubMed

Hirth, Richard A; Turenne, Marc N; Wheeler, John R C; Ma, Yu; Messana, Joseph M

2010-08-01

Because of adverse survival effects, anemia management and financial incentives to increase doses of erythropoiesis-stimulating agents (ESAs) have been controversial. Prior studies showed more aggressive anemia management in dialysis facilities owned by for-profit chains, but have been criticized for not accounting for practices of individual physicians and facilities. To improve understanding of how dialysis practices and resource utilization are influenced by physicians, facilities, and chains. Mixed models with chain fixed effects and facility and physician random effects. Medicare hemodialysis patients in 2004. A total of 234,158 patients, 3995 facilities, 4838 physicians, and 7 chain classifications were included. Spending per session for dialysis-related services billed separately from the dialysis treatment and for ESAs. Achievement of hematocrit (HCT) and urea reduction ratio (URR) targets. Of the 4 largest for-profit chains, 3 had higher resource use than independents, with differences up to $17.92 higher ESA/session. Utilization was positively associated with achieving target HCT. Despite incurring lower costs, patients treated by a large nonprofit chain were as likely as patients of independents to achieve the HCT target. The largest chains were more likely than independents to achieve the URR target. Substantial variation occurred across physicians and facilities, and adjustment for chain only modestly decreased this variation. Chains' methods of influencing practices were not directly observed. Chains appear to have the ability to implement protocols that shift practices, but not the ability to substantially reduce local variation. Assertions that chain effects found by earlier studies were spurious are not supported.

Smear Conversion, Treatment Outcomes and the Time of Default in Registered Tuberculosis Patients on RNTCP DOTS in Puducherry, Southern India

PubMed Central

Jayakumar, Niranjana; Gnanasekaran, Dhivyalakshmi

2014-01-01

Background: Revised National Tuberculosis Control Programme (RNTCP) in India has achieved improved cure rates. Objectives: This study describes the achievements under RNTCP in terms of conversion rates, treatment outcomes and pattern of time of default in patients on directly observed short-course treatment for Tuberculosis in Puducherry, Southern India. Settings: Retrospective cohort study; Tuberculosis Unit in District Tuberculosis Centre, Puducherry, India. Materials and Methods: Cohort analysis of patients of registered at the Tuberculosis Unit during 1st and 2nd quarter of the year 2011. Details about sputum conversion, treatment outcome and time of default were obtained from the tuberculosis register. Statistical Analysis: Kaplan-Meier plots & log rank tests. Results: RNTCP targets with respect to success rate (85.7%), death rate (2.7%) and failure rate (2.1%) in new cases have been achieved but the sputum conversion rate (88%) and default rate (5.9%) targets have not been achieved. The overall default rate for all registered TB patients was 7.4%; significantly higher in category II. In retreatment cases registered as treatment after default, the default rate was high (9%). The cumulative default rate; though similar in the initial two months of treatment; was consistently higher in category II as compared to that in category I. Nearly 40% of all defaulters interrupted treatment between the second and fourth month after treatment initiation. Conclusion: Defaulting from treatment is more common among the retreatment cases and usually occurs during the transition phase from intensive phase to continuation phase. PMID:25478371

The effect of inquiry-based, hands-on labs on achievement in middle school science

NASA Astrophysics Data System (ADS)

Miller, Donna Kaye Green

The purpose of this quasi-experimental study was to measure the difference in science achievement between students who had been taught with an inquiry-based, hands-on pedagogical approach and those who had not. Improving student academic achievement and standardized test scores is the major objective of teachers, parents, school administrators, government entities, and students themselves. One major barrier to this academic success in Georgia, and the entire United States, has been the paucity of success in middle level science classes. Many studies have been conducted to determine the learning approaches that will best enable students to not only acquire a deeper understanding of science concepts, but to equip them to apply that new knowledge in their daily activities. Inquiry-based, hands-on learning involves students participating in activities that reflect methods of scientific investigation. The effective utilization of the inquiry-based learning approach demands inclusion of learners in a self-directed learning environment, the ability to think critically, and an understanding of how to reflect and reason scientifically. The treatment group using an inquiry-based, hands-on program did score slightly higher on the CRCT. However, the results revealed that there was not a significant difference in student achievement. This study showed that the traditionally instructed control group had slightly higher interest in science than the inquiry-based treatment group. The findings of this research study indicated that the NCLB mandates might need to be altered if there are no significant academic gains that result from the use of inquiry-based strategies.

Educational Progress of Looked-After Children in England: A Study Using Group Trajectory Analysis.

PubMed

Sutcliffe, Alastair G; Gardiner, Julian; Melhuish, Edward

2017-09-01

Looked-after children in local authority care are among the most disadvantaged, and measures of their well-being, including educational outcomes, are poorer than other children's. The study sample consisted of all children in England born in academic years 1993 to 1994 through 1997 to 1998 who were in local authority care at any point during the academic years 2005 to 2006 through 2012 to 2013 and for whom results of national tests in literacy and numeracy were available at ages 7, 11, and 16 ( N = 47 500). Group trajectory analysis of children's educational progress identified 5 trajectory groups: low achievement, late improvement, late decline, predominant, and high achievement. Being looked after earlier was associated with a higher probability of following a high achievement trajectory and a lower probability of following a late decline trajectory. For children first looked after between ages 7 and 16, having a longer total time looked after by age 16 was associated with a higher probability of following a high achievement trajectory. For children with poor outcomes at ages 7 and 11, being looked after by age 16 was associated with an increased chance of educational improvement by age 16. This study provides evidence that early entry into care can reduce the risk of poor educational outcomes. It also establishes group trajectory analysis as an effective method for analyzing the educational progress of looked-after children, with the particular strength that it allows factors associated with a late decline or improvement in educational progress to be identified. Copyright © 2017 by the American Academy of Pediatrics.

Comparison of sentinel lymph node biopsy guided by blue dye with or without indocyanine green in early breast cancer.

PubMed

Shen, Songjie; Xu, Qianqian; Zhou, Yidong; Mao, Feng; Guan, Jinghong; Sun, Qiang

2018-05-22

There were limited data available for a head-to-head comparison of the identification rate and survival between the combined method of indocyanine green fluorescence and blue dye versus the traditional blue dye alone method for sentinel lymph node (SLN) biopsy. From January 2013 to December 2015, 523 eligible breast cancer patients were included in this nonrandomized prospective analysis. The identification rates, the number of SLNs identified, and the disease-free survival (DFS) between the two mapping methods were compared. The identification rate of SLNs was significantly higher with the combined method than that with the blue dye alone method (99.2% vs 93.3%, respectively; P < 0.001). The average number of SLNs identified per patient in the combined method group was 3.7 ± 2.4, which was more than that in the blue dye alone group (3.2 ± 1.6; P = 0.004). With a median follow-up of 29 months, 0.5% patients in the combined group, and 1.3% patients in the blue dye group had axillary recurrences. The DFS between the two groups showed no significant difference (P = 0.161). The combined method achieved a higher identification rate and lower rate of axillary recurrence compared to the blue dye alone method. © 2018 Wiley Periodicals, Inc.

Interpolation of diffusion weighted imaging datasets.

PubMed

Dyrby, Tim B; Lundell, Henrik; Burke, Mark W; Reislev, Nina L; Paulson, Olaf B; Ptito, Maurice; Siebner, Hartwig R

2014-12-01

Diffusion weighted imaging (DWI) is used to study white-matter fibre organisation, orientation and structural connectivity by means of fibre reconstruction algorithms and tractography. For clinical settings, limited scan time compromises the possibilities to achieve high image resolution for finer anatomical details and signal-to-noise-ratio for reliable fibre reconstruction. We assessed the potential benefits of interpolating DWI datasets to a higher image resolution before fibre reconstruction using a diffusion tensor model. Simulations of straight and curved crossing tracts smaller than or equal to the voxel size showed that conventional higher-order interpolation methods improved the geometrical representation of white-matter tracts with reduced partial-volume-effect (PVE), except at tract boundaries. Simulations and interpolation of ex-vivo monkey brain DWI datasets revealed that conventional interpolation methods fail to disentangle fine anatomical details if PVE is too pronounced in the original data. As for validation we used ex-vivo DWI datasets acquired at various image resolutions as well as Nissl-stained sections. Increasing the image resolution by a factor of eight yielded finer geometrical resolution and more anatomical details in complex regions such as tract boundaries and cortical layers, which are normally only visualized at higher image resolutions. Similar results were found with typical clinical human DWI dataset. However, a possible bias in quantitative values imposed by the interpolation method used should be considered. The results indicate that conventional interpolation methods can be successfully applied to DWI datasets for mining anatomical details that are normally seen only at higher resolutions, which will aid in tractography and microstructural mapping of tissue compartments. Copyright © 2014. Published by Elsevier Inc.

The Untold Stories of Former Teen Mothers Who Have Achieved a Master's Degree or Higher

ERIC Educational Resources Information Center

Benitez, Tanya

2017-01-01

Purpose: The purpose of this study was to shed light on former teen mothers who have "beaten the odds" by achieving a master's degree or higher. It sought to reveal and understand what the external and internal factors are which lead to these women pursing higher education. Methodology: The methodology of this study is a case study which…

Adrenaline, terlipressin, and corticoids versus adrenaline in the treatment of experimental pediatric asphyxial cardiac arrest.

PubMed

González, Rafael; Urbano, Javier; Botrán, Marta; López, Jorge; Solana, Maria J; García, Ana; Fernández, Sarah; López-Herce, Jesús

2014-07-01

To analyze if treatment with adrenaline (epinephrine) plus terlipressin plus corticoids achieves higher return of spontaneous circulation than adrenaline in an experimental infant animal model of asphyxial cardiac arrest. Prospective randomized animal study. Experimental department in a University Hospital. Forty-nine piglets were studied. Cardiac arrest was induced by at least 10 minutes of removal of mechanical ventilation and was followed by manual external chest compressions and mechanical ventilation. After 3 minutes of resuscitation, piglets that did not achieve return of spontaneous circulation were randomized to two groups: adrenaline 0.02 mg kg every 3 minutes (20 animals) and adrenaline 0.02 mg kg every 3 minutes plus terlipressin 20 μg kg every 6 minutes plus hydrocortisone 30 mg kg one dose (22 animals). Resuscitation was discontinued when return of spontaneous circulation was achieved or after 24 minutes. Return of spontaneous circulation was achieved in 14 piglets (28.5%), 14.2% with only cardiac massage and ventilation. Return of spontaneous circulation was achieved in 25% of piglets treated with adrenaline and in 9.1% of those treated with adrenaline plus terlipressin plus hydrocortisone (p = 0.167). Return of spontaneous circulation was achieved in 45.4% of animals with pulseless electric activity, 20% with asystole, and 0% with ventricular fibrillation (p = 0.037). Shorter duration of cardiac arrest, higher mean blood pressure and EtCO2 and lower PaCO2 before resuscitation, and higher mean blood pressure during resuscitation were associated with higher return of spontaneous circulation. Treatment with adrenaline plus terlipressin plus corticoids does not achieve higher return of spontaneous circulation than that with adrenaline in an infant animal model of asphyxial cardiac arrest.

Compact Representation of High-Dimensional Feature Vectors for Large-Scale Image Recognition and Retrieval.

PubMed

Zhang, Yu; Wu, Jianxin; Cai, Jianfei

2016-05-01

In large-scale visual recognition and image retrieval tasks, feature vectors, such as Fisher vector (FV) or the vector of locally aggregated descriptors (VLAD), have achieved state-of-the-art results. However, the combination of the large numbers of examples and high-dimensional vectors necessitates dimensionality reduction, in order to reduce its storage and CPU costs to a reasonable range. In spite of the popularity of various feature compression methods, this paper shows that the feature (dimension) selection is a better choice for high-dimensional FV/VLAD than the feature (dimension) compression methods, e.g., product quantization. We show that strong correlation among the feature dimensions in the FV and the VLAD may not exist, which renders feature selection a natural choice. We also show that, many dimensions in FV/VLAD are noise. Throwing them away using feature selection is better than compressing them and useful dimensions altogether using feature compression methods. To choose features, we propose an efficient importance sorting algorithm considering both the supervised and unsupervised cases, for visual recognition and image retrieval, respectively. Combining with the 1-bit quantization, feature selection has achieved both higher accuracy and less computational cost than feature compression methods, such as product quantization, on the FV and the VLAD image representations.

A Simple Method to Reduce both Lactic Acid and Ammonium Production in Industrial Animal Cell Culture

PubMed Central

Freund, Nathaniel W.; Croughan, Matthew S.

2018-01-01

Fed-batch animal cell culture is the most common method for commercial production of recombinant proteins. However, higher cell densities in these platforms are still limited due to factors such as excessive ammonium production, lactic acid production, nutrient limitation, and/or hyperosmotic stress related to nutrient feeds and base additions to control pH. To partly overcome these factors, we investigated a simple method to reduce both ammonium and lactic acid production—termed Lactate Supplementation and Adaptation (LSA) technology—through the use of CHO cells adapted to a lactate-supplemented medium. Using this simple method, we achieved a reduction of nearly 100% in lactic acid production with a simultaneous 50% reduction in ammonium production in batch shaker flasks cultures. In subsequent fed-batch bioreactor cultures, lactic acid production and base addition were both reduced eight-fold. Viable cell densities of 35 million cells per mL and integral viable cell days of 273 million cell-days per mL were achieved, both among the highest currently reported for a fed-batch animal cell culture. Investigating the benefits of LSA technology in animal cell culture is worthy of further consideration and may lead to process conditions more favorable for advanced industrial applications. PMID:29382079

A Simple Method to Reduce both Lactic Acid and Ammonium Production in Industrial Animal Cell Culture.

PubMed

Freund, Nathaniel W; Croughan, Matthew S

2018-01-28

Fed-batch animal cell culture is the most common method for commercial production of recombinant proteins. However, higher cell densities in these platforms are still limited due to factors such as excessive ammonium production, lactic acid production, nutrient limitation, and/or hyperosmotic stress related to nutrient feeds and base additions to control pH. To partly overcome these factors, we investigated a simple method to reduce both ammonium and lactic acid production-termed Lactate Supplementation and Adaptation (LSA) technology-through the use of CHO cells adapted to a lactate-supplemented medium. Using this simple method, we achieved a reduction of nearly 100% in lactic acid production with a simultaneous 50% reduction in ammonium production in batch shaker flasks cultures. In subsequent fed-batch bioreactor cultures, lactic acid production and base addition were both reduced eight-fold. Viable cell densities of 35 million cells per mL and integral viable cell days of 273 million cell-days per mL were achieved, both among the highest currently reported for a fed-batch animal cell culture. Investigating the benefits of LSA technology in animal cell culture is worthy of further consideration and may lead to process conditions more favorable for advanced industrial applications.

Groupwise Registration and Atlas Construction of 4th-Order Tensor Fields Using the ℝ+ Riemannian Metric*

PubMed Central

Barmpoutis, Angelos

2010-01-01

Registration of Diffusion-Weighted MR Images (DW-MRI) can be achieved by registering the corresponding 2nd-order Diffusion Tensor Images (DTI). However, it has been shown that higher-order diffusion tensors (e.g. order-4) outperform the traditional DTI in approximating complex fiber structures such as fiber crossings. In this paper we present a novel method for unbiased group-wise non-rigid registration and atlas construction of 4th-order diffusion tensor fields. To the best of our knowledge there is no other existing method to achieve this task. First we define a metric on the space of positive-valued functions based on the Riemannian metric of real positive numbers (denoted by ℝ+). Then, we use this metric in a novel functional minimization method for non-rigid 4th-order tensor field registration. We define a cost function that accounts for the 4th-order tensor re-orientation during the registration process and has analytic derivatives with respect to the transformation parameters. Finally, the tensor field atlas is computed as the minimizer of the variance defined using the Riemannian metric. We quantitatively compare the proposed method with other techniques that register scalar-valued or diffusion tensor (rank-2) representations of the DWMRI. PMID:20436782

Chronotropic incompetence and a higher frequency of myocardial ischemia in exercise echocardiography

PubMed Central

Oliveira, Joselina LM; Góes, Thiago JS; Santana, Thaiana A; Travassos, Thiago F; Teles, Lívia D; Anjos-Andrade, Fernando D; Nascimento-Júnior, Adão C; Alves, Érica O; Barreto, Martha A; Barreto-Filho, José A; D'Oliveira, Argemiro; Sousa, Antônio CS

2007-01-01

Background Exercise echocardiography (EE) is an established method to diagnose coronary artery disease (CAD). Chronotropic incompetence (CI) during the EE may be a marker of myocardial ischemia. The purpose of this investigation was to evaluate the additive value of CI during EE in CAD diagnosis. Methods Between 2000 and 2006, 4042 patients (1900 men with a mean age of 56 ± 11 years) were evaluated by EE. Based on the heart rate (HR) reached during the exercise test, the subjects were divided into two groups: G1 group – 490 patients who failed to achieve 85% of the maximal age-predicted HR, and G2 group – 3552 patients who were able to achieve 85% of the maximal age-predicted HR. Clinical characteristics, left ventricular wall motion abnormalities – wall motion score index (WMSI) – and coronary angiography (CA) were the parameters compared between the two groups. Results The left ventricular wall motion abnormalities were more frequent in G1 group than in G2 group (54% versus 26%; P < 0.00001). WMSI was higher in G1 group than in G2 group, both at rest (1.06 ± 0.17 versus 1.02 ± 0.09; P < 0.0001) and after exercise (1.12 ± 0.23 versus 1.04 ± 0.21; P < 0.0001). In G1 group, 82% of the patients with positive EE for myocardial ischemia presented obstructive coronary, compared to 71% (P = 0.03) in G2 group. Conclusion CI is associated with a higher frequency of myocardial ischemia during EE, reinforcing the concept that CI is a marker of the severity of myocardial ischemia. PMID:17980022

Problem-based learning using patient-simulated videos showing daily life for a comprehensive clinical approach

PubMed Central

Ohira, Yoshiyuki; Uehara, Takanori; Noda, Kazutaka; Suzuki, Shingo; Shikino, Kiyoshi; Kajiwara, Hideki; Kondo, Takeshi; Hirota, Yusuke; Ikusaka, Masatomi

2017-01-01

Objectives We examined whether problem-based learning tutorials using patient-simulated videos showing daily life are more practical for clinical learning, compared with traditional paper-based problem-based learning, for the consideration rate of psychosocial issues and the recall rate for experienced learning. Methods Twenty-two groups with 120 fifth-year students were each assigned paper-based problem-based learning and video-based problem-based learning using patient-simulated videos. We compared target achievement rates in questionnaires using the Wilcoxon signed-rank test and discussion contents diversity using the Mann-Whitney U test. A follow-up survey used a chi-square test to measure students’ recall of cases in three categories: video, paper, and non-experienced. Results Video-based problem-based learning displayed significantly higher achievement rates for imagining authentic patients (p=0.001), incorporating a comprehensive approach including psychosocial aspects (p<0.001), and satisfaction with sessions (p=0.001). No significant differences existed in the discussion contents diversity regarding the International Classification of Primary Care Second Edition codes and chapter types or in the rate of psychological codes. In a follow-up survey comparing video and paper groups to non-experienced groups, the rates were higher for video (χ2=24.319, p<0.001) and paper (χ2=11.134, p=0.001). Although the video rate tended to be higher than the paper rate, no significant difference was found between the two. Conclusions Patient-simulated videos showing daily life facilitate imagining true patients and support a comprehensive approach that fosters better memory. The clinical patient-simulated video method is more practical and clinical problem-based tutorials can be implemented if we create patient-simulated videos for each symptom as teaching materials.  PMID:28245193

Intra Frame Coding In Advanced Video Coding Standard (H.264) to Obtain Consistent PSNR and Reduce Bit Rate for Diagonal Down Left Mode Using Gaussian Pulse

NASA Astrophysics Data System (ADS)

Manjanaik, N.; Parameshachari, B. D.; Hanumanthappa, S. N.; Banu, Reshma

2017-08-01

Intra prediction process of H.264 video coding standard used to code first frame i.e. Intra frame of video to obtain good coding efficiency compare to previous video coding standard series. More benefit of intra frame coding is to reduce spatial pixel redundancy with in current frame, reduces computational complexity and provides better rate distortion performance. To code Intra frame it use existing process Rate Distortion Optimization (RDO) method. This method increases computational complexity, increases in bit rate and reduces picture quality so it is difficult to implement in real time applications, so the many researcher has been developed fast mode decision algorithm for coding of intra frame. The previous work carried on Intra frame coding in H.264 standard using fast decision mode intra prediction algorithm based on different techniques was achieved increased in bit rate, degradation of picture quality(PSNR) for different quantization parameters. Many previous approaches of fast mode decision algorithms on intra frame coding achieved only reduction of computational complexity or it save encoding time and limitation was increase in bit rate with loss of quality of picture. In order to avoid increase in bit rate and loss of picture quality a better approach was developed. In this paper developed a better approach i.e. Gaussian pulse for Intra frame coding using diagonal down left intra prediction mode to achieve higher coding efficiency in terms of PSNR and bitrate. In proposed method Gaussian pulse is multiplied with each 4x4 frequency domain coefficients of 4x4 sub macro block of macro block of current frame before quantization process. Multiplication of Gaussian pulse for each 4x4 integer transformed coefficients at macro block levels scales the information of the coefficients in a reversible manner. The resulting signal would turn abstract. Frequency samples are abstract in a known and controllable manner without intermixing of coefficients, it avoids picture getting bad hit for higher values of quantization parameters. The proposed work was implemented using MATLAB and JM 18.6 reference software. The proposed work measure the performance parameters PSNR, bit rate and compression of intra frame of yuv video sequences in QCIF resolution under different values of quantization parameter with Gaussian value for diagonal down left intra prediction mode. The simulation results of proposed algorithm are tabulated and compared with previous algorithm i.e. Tian et al method. The proposed algorithm achieved reduced in bit rate averagely 30.98% and maintain consistent picture quality for QCIF sequences compared to previous algorithm i.e. Tian et al method.

Achieving fruit, juice, and vegetable recipe preparation goals influences consumption by 4th grade students

PubMed Central

Cullen, Karen W; Watson, Kathy B; Zakeri, Issa; Baranowski, Tom; Baranowski, Janice H

2007-01-01

Background Including children in food preparation activities has long been recommended as a method to encourage children's consumption, but has not been evaluated. Goal setting is also a common component of behavior change programs. This study assessed the impact of attaining goals to prepare fruit-juice or vegetable recipes on student fruit and vegetable consumption as part of a 10-week fruit and vegetable intervention for fourth grade students. Methods At six of the 10 sessions, students (n = 671) selected a fruit-juice or vegetable recipe to prepare at home before the next session. Students returned parent-signed notes reporting their child's goal attainment. Baseline and post consumption were assessed with up to four days of dietary recalls. Analyses included regression models predicting post consumption from the number of fruit-juice or vegetable recipe preparation goals attained, controlling for baseline consumption. Results In general, girls and Hispanic students achieved the most recipe preparation goals. For students with highest baseline fruit-juice consumption, post fruit-juice consumption was higher by about 1.0 serving for those achieving 2 or 3 fruit-juice recipe preparation goals. Post vegetable consumption was highest for students reporting the highest baseline vegetable consumption and who achieved two or three vegetable recipe preparation goals. In general, recipe goal setting was a useful procedure primarily for those with high baseline consumption. Conclusion This is one of the first reports demonstrating that home recipe preparation was correlated with dietary change among children. PMID:17603875

Mother-Adolescent Language Proficiency and Adolescent Academic and Emotional Adjustment Among Chinese American Families

PubMed Central

Benner, Aprile D.; Lau, Anna S.; Kim, Su Yeong

2009-01-01

This study examined the role of adolescents’ and mothers’ self-reports of English and heritage language proficiency in youth’s academic and emotional adjustment among 444 Chinese American families. Adolescents who were proficient in English tended to exhibit higher reading achievement scores, math achievement scores, and overall GPA. Mothers who were English proficient tended to have children with higher academic achievement and fewer depressive symptoms. Results also indicated that adolescents’ heritage language maintenance was associated with positive adjustment, particularly amongst foreign-born youth and for youth whose parents were highly proficient in the heritage language. Mother-adolescent match in heritage language proficiency was related to higher math achievement scores and overall GPA. Additionally, higher heritage language proficiency was associated with fewer depressive symptoms for foreign-born but not U.S.-born youth. Overall, the findings suggest that proficiency in both the English and heritage language may confer advantages to Chinese American youth. PMID:19636729

Instructional Methods Within the Elementary-School Science Classroom Related to Improved Academic Performance

NASA Astrophysics Data System (ADS)

Baum, Lisa

There is gap in passing rates on the standardized science assessment between European American and Hispanic American students. The purpose of this study was to examine student performance in science and the closing of the achievement gap between European American and Hispanic American students based upon receipt of an inquiry or noninquiry instruction method. Guided by the theoretical framework of constructive learning, this quantitative ex post facto research design gathered data from 8 teachers who had already implemented 1 of the 2 methods of instruction. The teachers were chosen through purposive sampling based on previous observations of instructional method and were placed into 2 groups depending upon the type of instruction: inquiry or noninquiry. Descriptive statistics were used to determine mean differences and a 2-way analysis of variance was used to determine mean differences in science test scores between European American and Hispanic American students and between the instructional methods to which they had been exposed. Results found that the inquiry instructional method was related to a significant increase in mean scores for both ethnic groups, but the achievement gap between the two groups was not closed by the inquiry instruction method. This study can promote positive social change for students by informing the efforts of educational leaders and teachers to create professional development using inquiry instruction. Students may perform higher on standardized tests when they are allowed to explore science by asking questions and answering their own questions through the collection and analysis of data.

Photocatalytic degradation of methylene blue dye by zinc oxide nanoparticles obtained from precipitation and sol-gel methods.

PubMed

Balcha, Abebe; Yadav, Om Prakash; Dey, Tania

2016-12-01

Zinc oxide (ZnO) nanoparticles were synthesized by precipitation and sol-gel methods. The aim of this study was to understand how different synthetic methods can affect the photocatalytic activity of ZnO nanoparticles. As-synthesized ZnO nanoparticles were characterized by X-ray diffraction (XRD) and UV-Visible spectroscopic techniques. XRD patterns of ZnO powders synthesized by precipitation and sol-gel methods revealed their hexagonal wurtzite structure with crystallite sizes of 30 and 28 nm, respectively. Their photocatalytic activities were evaluated by photocatalytic degradation of methylene blue, a common water pollutant, under UV radiation. The effects of operational parameters such as photocatalyst load and initial concentration of the dye on photocatalytic degradation of methylene blue were investigated. While the degradation of dye decreased over the studied dye concentration range of 20 to 100 mg/L, an optimum photocatalyst load of 250 mg/L was needed to achieve dye degradation as high as 81 and 92.5 % for ZnO prepared by precipitation and sol-gel methods, respectively. Assuming pseudo first-order reaction kinetics, this corresponded to rate constants of 8.4 × 10 -3 and 12.4 × 10 -3  min -1 , respectively. Hence, sol-gel method is preferred over precipitation method in order to achieve higher photocatalytic activity of ZnO nanostructures. Photocatalytic activity is further augmented by better choice of capping ligand for colloidal stabilization, starch being more effective than polyethylene glycol (PEG).

Effect of the starting point of half-pin insertion on the insertional torque of the pin at the tibia.

PubMed

Kim, Sung Jae; Kim, Sung Hwan; Kim, Young Hwan; Chun, Yong Min

2015-01-01

The authors have observed a failure to achieve secure fixation in elderly patients when inserting a half-pin at the anteromedial surface of the tibia. The purpose of this study was to compare two methods for inserting a half-pin at tibia diaphysis in elderly patients. Twenty cadaveric tibias were divided into Group C or V. A half-pin was inserted into the tibias of Group C via the conventional method, from the anteromedial surface to the interosseous border of the tibia diaphysis, and into the tibias of Group V via the vertical method, from the anterior border to the posterior surface at the same level. The maximum insertion torque was measured during the bicortical insertion with a torque driver. The thickness of the cortex was measured by micro-computed tomography. The relationship between the thickness of the cortex engaged and the insertion torque was investigated. The maximum insertion torque and the thickness of the cortex were significantly higher in Group V than Group C. Both groups exhibited a statistically significant linear correlation between torque and thickness by Spearman's rank correlation analysis. Half-pins inserted by the vertical method achieved purchase of more cortex than those inserted by the conventional method. Considering that cortical thickness and insertion torque in Group V were significantly greater than those in Group C, we suggest that the vertical method of half-pin insertion may be an alternative to the conventional method in elderly patients.

Motivation and social contexts: a crossnational pilot study of achievement, power, and affiliation motives.

PubMed

Xu, Xiaoyan; Xu, Yangang; Mellor, David; Duan, Liqiong

2012-01-01

Previous research suggests that there is a relationship between social contexts (e.g., economic growth, engagement in wars) and motives within populations. In particular, high achievement motive is associated with subsequent economic growth, which in turn increases power motive. Increased national achievement and power motives have been argued to precede social changes that lead to decreased affiliation motives, and engagement in wars. The present study aimed to examine differences in achievement, power, and affiliation motives between 266 college students in China (a nation with sustained high economic growth) and 255 college students in the USA (a nation with previously strong but now slowing economic growth, and engaged in war). Analysis of personal strivings suggested that Chinese college students showed significantly higher levels of achievement motive than the American college students, but American college students showed significantly higher levels of affiliation motive than Chinese college students. Overall, males exhibited higher achievement motivation than females. No significant interaction effects were found for gender by location for any of the three motives. The findings are discussed in relation to previous research.

Comparison of Pharmaceutical Calculations Learning Outcomes Achieved Within a Traditional Lecture or Flipped Classroom Andragogy.

PubMed

Anderson, H Glenn; Frazier, Lisa; Anderson, Stephanie L; Stanton, Robert; Gillette, Chris; Broedel-Zaugg, Kim; Yingling, Kevin

2017-05-01

Objective. To compare learning outcomes achieved from a pharmaceutical calculations course taught in a traditional lecture (lecture model) and a flipped classroom (flipped model). Methods. Students were randomly assigned to the lecture model and the flipped model. Course instructors, content, assessments, and instructional time for both models were equivalent. Overall group performance and pass rates on a standardized assessment (Pcalc OSCE) were compared at six weeks and at six months post-course completion. Results. Student mean exam scores in the flipped model were higher than those in the lecture model at six weeks and six months later. Significantly more students passed the OSCE the first time in the flipped model at six weeks; however, this effect was not maintained at six months. Conclusion. Within a 6 week course of study, use of a flipped classroom improves student pharmacy calculation skill achievement relative to a traditional lecture andragogy. Further study is needed to determine if the effect is maintained over time.

Comparison of Pharmaceutical Calculations Learning Outcomes Achieved Within a Traditional Lecture or Flipped Classroom Andragogy

PubMed Central

Frazier, Lisa; Anderson, Stephanie L.; Stanton, Robert; Gillette, Chris; Broedel-Zaugg, Kim; Yingling, Kevin

2017-01-01

Objective. To compare learning outcomes achieved from a pharmaceutical calculations course taught in a traditional lecture (lecture model) and a flipped classroom (flipped model). Methods. Students were randomly assigned to the lecture model and the flipped model. Course instructors, content, assessments, and instructional time for both models were equivalent. Overall group performance and pass rates on a standardized assessment (Pcalc OSCE) were compared at six weeks and at six months post-course completion. Results. Student mean exam scores in the flipped model were higher than those in the lecture model at six weeks and six months later. Significantly more students passed the OSCE the first time in the flipped model at six weeks; however, this effect was not maintained at six months. Conclusion. Within a 6 week course of study, use of a flipped classroom improves student pharmacy calculation skill achievement relative to a traditional lecture andragogy. Further study is needed to determine if the effect is maintained over time. PMID:28630511

Implicit motive profile of treatment-seeking opiate users: high affiliation and low achievement.

PubMed

Bársonya, Katalin; Martos, Tamás; Ehmann, Bea; Balázs, Hedvig; Demetrovics, Zsolt

2013-01-01

Research on basic human motives (achievement, affiliation, and power) encoded at the emotional level recently returned to the forefront of scientific research. To date, there are only a few studies on the pattern of implicit motives of substance users, so the present study examined opiate users participating in methadone maintenance treatment (N = 80) along these dimensions, comparing them to 40 non-substance users. Participants were asked to create stories on the basis of the pictures of the Thematic Apperception Test. The stories were analyzed using the content analysis method of David Winter (1991). Like other substance user groups, opiate-dependent persons used less achievement and more affiliation notions in creating stories, while there was no significant difference between the two groups concerning power notions. The results proved to be independent of the presence of anxiety and depression symptoms, despite substance users reporting higher levels of these, and suggest that motivational factors are worth considering in treatment planning.

Nonbismuth concomitant quadruple therapy for Helicobacter pylori eradication in Chinese regions: A meta-analysis of randomized controlled trials

PubMed Central

Lin, Lien-Chieh; Hsu, Tzu-Herng; Huang, Kuang-Wei; Tam, Ka-Wai

2016-01-01

AIM: To evaluate the applicability of nonbismuth concomitant quadruple therapy for Helicobacter pylori (H. pylori) eradication in Chinese regions. METHODS: A systematic review and meta-analysis of randomized controlled trials was performed to evaluate the efficacy of nonbismuth concomitant quadruple therapy between sequential therapy or triple therapy for H. pylori eradication in Chinese regions. The defined Chinese regions include China, Hong Kong, Taiwan, and Singapore. The primary outcome was the H. pylori eradication rate; the secondary outcome was the compliance with therapy. The PubMed, Embase, Scopus, and Cochrane databases were searched for studies published in the period up to March 2016 with no language restriction. RESULTS: We reviewed six randomized controlled trials and 1616 patients. In 3 trials comparing concomitant quadruple therapy with triple therapy, the H. pylori eradication rate was significantly higher for 7-d nonbismuth concomitant quadruple therapy than for 7-d triple therapy (91.2% vs 77.9%, risk ratio = 1.17, 95%CI: 1.09-1.25). In 3 trials comparing quadruple therapy with sequential therapy, the eradication rate was not significant between groups (86.9% vs 86.0%). However, higher compliance was achieved with concomitant therapy than with sequential therapy. CONCLUSION: The H. pylori eradication rate was higher for nonbismuth concomitant quadruple therapy than for triple therapy. Moreover, higher compliance was achieved with nonbismuth concomitant quadruple therapy than with sequential therapy. Thus, nonbismuth concomitant quadruple therapy should be the first-line treatment in Chinese regions. PMID:27340362

Niv versus dropping vitrification in cryopreservation of human ovarian tissue.

PubMed

Xiao, Z; Li, S W; Zhang, Y Y; Wang, Y; Li, L L; Fan, W

2014-01-01

The containers for vitrification of tissues include cryovials, copper grids, Pasteur pipettes, the solid-surface method and etc. Recently the acupuncture needle was used to achieve better result in vitrification of human ovarian tissue. To determine if the needle immersed vitrification method (NIV) is a promising approach to vitrify the human ovarian tissue. Human ovarian biopsies from five patients were vitrified using NIV and Dropping vitrification. After 14 days of in vitro culture, the incidence of apoptotic primordial follicles from fresh and vitrified groups was assessed by TUNEL assay. 17β-estradiol (E2) and progesterone (P4) were detected in the media after culturing of vitrified and fresh ovarian tissues. The incidence of apoptotic primordial follicles was significantly higher in the dropping vitrification group than in the NIV group (P < 0.05). E2 and P4 concentrations were significantly higher in NIV groups than in Dropping vitrification group (P < 0.05). NIV was an appropriate method to vitrify ovarian tissue by improving the growth potential of frozen-warmed ovarian tissue in vitro culture.

Application of FDM three-dimensional printing technology in the digital manufacture of custom edentulous mandible trays

PubMed Central

Chen, Hu; Yang, Xu; Chen, Litong; Wang, Yong; Sun, Yuchun

2016-01-01

The objective was to establish and evaluate a method for manufacture of custom trays for edentulous jaws using computer aided design and fused deposition modeling (FDM) technologies. A digital method for design the custom trays for edentulous jaws was established. The tissue surface data of ten standard mandibular edentulous plaster models, which was used to design the digital custom tray in a reverse engineering software, were obtained using a 3D scanner. The designed tray was printed by a 3D FDM printing device. Another ten hand-made custom trays were produced as control. The 3-dimentional surface data of models and custom trays was scanned to evaluate the accuracy of reserved impression space, while the difference between digitally made trays and hand-made trays were analyzed. The digitally made custom trays achieved a good matching with the mandibular model, showing higher accuracy than the hand-made ones. There was no significant difference of the reserved space between different models and its matched digitally made trays. With 3D scanning, CAD and FDM technology, an efficient method of custom tray production was established, which achieved a high reproducibility and accuracy. PMID:26763620

α-Information Based Registration of Dynamic Scans for Magnetic Resonance Cystography

PubMed Central

Han, Hao; Lin, Qin; Li, Lihong; Duan, Chaijie; Lu, Hongbing; Li, Haifang; Yan, Zengmin; Fitzgerald, John

2015-01-01

To continue our effort on developing magnetic resonance (MR) cystography, we introduce a novel non–rigid 3D registration method to compensate for bladder wall motion and deformation in dynamic MR scans, which are impaired by relatively low signal–to–noise ratio in each time frame. The registration method is developed on the similarity measure of α–information, which has the potential of achieving higher registration accuracy than the commonly-used mutual information (MI) measure for either mono-modality or multi-modality image registration. The α–information metric was also demonstrated to be superior to both the mean squares and the cross-correlation metrics in multi-modality scenarios. The proposed α–registration method was applied for bladder motion compensation via real patient studies, and its effect to the automatic and accurate segmentation of bladder wall was also evaluated. Compared with the prevailing MI-based image registration approach, the presented α–information based registration was more effective to capture the bladder wall motion and deformation, which ensured the success of the following bladder wall segmentation to achieve the goal of evaluating the entire bladder wall for detection and diagnosis of abnormality. PMID:26087506

Efficiency Enhancement for an Inductive Wireless Power Transfer System by Optimizing the Impedance Matching Networks.

PubMed

Miao, Zhidong; Liu, Dake; Gong, Chen

2017-10-01

Inductive wireless power transfer (IWPT) is a promising power technology for implantable biomedical devices, where the power consumption is low and the efficiency is the most important consideration. In this paper, we propose an optimization method of impedance matching networks (IMN) to maximize the IWPT efficiency. The IMN at the load side is designed to achieve the optimal load, and the IMN at the source side is designed to deliver the required amount of power (no-more-no-less) from the power source to the load. The theoretical analyses and design procedure are given. An IWPT system for an implantable glaucoma therapeutic prototype is designed as an example. Compared with the efficiency of the resonant IWPT system, the efficiency of our optimized system increases with a factor of 1.73. Besides, the efficiency of our optimized IWPT system is 1.97 times higher than that of the IWPT system optimized by the traditional maximum power transfer method. All the discussions indicate that the optimization method proposed in this paper could achieve a high efficiency and long working time when the system is powered by a battery.

Data fusion and photometric restoration

NASA Astrophysics Data System (ADS)

Pirzkal, Norbert; Hook, Richard N.

2001-11-01

The current generation of 8-10m optical ground-based telescopes have a symbiotic relationship with space telescopes. For direct imaging in the optical the former can collect photons relatively cheaply but the latter can still achieve, even in the era of adaptive optics, significantly higher spatial resolution, point-spread function stability and astrometric fidelity over fields of a few arcminutes. The large archives of HST imaging already in place, when combined with the ease of access to ground-based data afforded by the virtual observatory currently under development, will make space-ground data fusion a powerful tool for the future. We describe a photometric image restoration method that we have developed which allows the efficient and accurate use of high-resolution space imaging of crowded fields to extract high quality photometry from very crowded ground-based images. We illustrate the method using HST and ESO VLT/FORS imaging of a globular cluster and demonstrate quantitatively the photometric measurements quality that can achieved using the data fusion approach instead of just using data from just one telescope. This method can handle most of the common difficulties encountered when attempting this problem such as determining the geometric mapping to the requisite precision, deriving the PSF and the background.

Optimization of Quenching Parameters for the Reduction of Titaniferous Magnetite Ore by Lean Grade Coal Using the Taguchi Method and Its Isothermal Kinetic Study

NASA Astrophysics Data System (ADS)

Sarkar, Bitan Kumar; Kumar, Nikhil; Dey, Rajib; Das, Gopes Chandra

2018-06-01

In the present study, a unique method is adopted to achieve higher reducibility of titaniferous magnetite lump ore (TMO). In this method, TMO is initially heated followed by water quenching. The quenching process generates cracks due to thermal shock in the dense TMO lumps, which, in turn, increases the extent of reduction (EOR) using the lean grade coal as a reductant. The optimum combination of parameters found by using Taguchi's L27 orthogonal array (OA) (five factors, three levels) is - 8 + 4 mm of particle size (PS1), 1423 K of quenching temperature (Qtemp2), 15 minutes of quenching time (Qtime3), 3 times the number of quenching {(No. of Q)3}, and 120 minutes of reduction time (Rtime3) at fixed reduction temperature of 1473 K. At optimized levels of the parameters, 92.39 pct reduction is achieved. Isothermal reduction kinetics of the quenched TMO lumps at the optimized condition reveals mixed controlled mechanisms [initially contracting geometry (CG3) followed by diffusion (D3)]. Activation energies calculated are 69.895 KJ/mole for CG3 and 39.084 KJ/mole for D3.

Improve the prediction of RNA-binding residues using structural neighbours.

PubMed

Li, Quan; Cao, Zanxia; Liu, Haiyan

2010-03-01

The interactions between RNA-binding proteins (RBPs) with RNA play key roles in managing some of the cell's basic functions. The identification and prediction of RNA binding sites is important for understanding the RNA-binding mechanism. Computational approaches are being developed to predict RNA-binding residues based on the sequence- or structure-derived features. To achieve higher prediction accuracy, improvements on current prediction methods are necessary. We identified that the structural neighbors of RNA-binding and non-RNA-binding residues have different amino acid compositions. Combining this structure-derived feature with evolutionary (PSSM) and other structural information (secondary structure and solvent accessibility) significantly improves the predictions over existing methods. Using a multiple linear regression approach and 6-fold cross validation, our best model can achieve an overall correct rate of 87.8% and MCC of 0.47, with a specificity of 93.4%, correctly predict 52.4% of the RNA-binding residues for a dataset containing 107 non-homologous RNA-binding proteins. Compared with existing methods, including the amino acid compositions of structure neighbors lead to clearly improvement. A web server was developed for predicting RNA binding residues in a protein sequence (or structure),which is available at http://mcgill.3322.org/RNA/.

Training Deep Spiking Neural Networks Using Backpropagation.

PubMed

Lee, Jun Haeng; Delbruck, Tobi; Pfeiffer, Michael

2016-01-01

Deep spiking neural networks (SNNs) hold the potential for improving the latency and energy efficiency of deep neural networks through data-driven event-based computation. However, training such networks is difficult due to the non-differentiable nature of spike events. In this paper, we introduce a novel technique, which treats the membrane potentials of spiking neurons as differentiable signals, where discontinuities at spike times are considered as noise. This enables an error backpropagation mechanism for deep SNNs that follows the same principles as in conventional deep networks, but works directly on spike signals and membrane potentials. Compared with previous methods relying on indirect training and conversion, our technique has the potential to capture the statistics of spikes more precisely. We evaluate the proposed framework on artificially generated events from the original MNIST handwritten digit benchmark, and also on the N-MNIST benchmark recorded with an event-based dynamic vision sensor, in which the proposed method reduces the error rate by a factor of more than three compared to the best previous SNN, and also achieves a higher accuracy than a conventional convolutional neural network (CNN) trained and tested on the same data. We demonstrate in the context of the MNIST task that thanks to their event-driven operation, deep SNNs (both fully connected and convolutional) trained with our method achieve accuracy equivalent with conventional neural networks. In the N-MNIST example, equivalent accuracy is achieved with about five times fewer computational operations.

Superresolution confocal technology for displacement measurements based on total internal reflection.

PubMed

Kuang, Cuifang; Ali, M Yakut; Hao, Xiang; Wang, Tingting; Liu, Xu

2010-10-01

In order to achieve a higher axial resolution for displacement measurement, a novel method is proposed based on total internal reflection filter and confocal microscope principle. A theoretical analysis of the basic measurement principles is presented. The analysis reveals that the proposed confocal detection scheme is effective in enhancing the resolution of nonlinearity of the reflectance curve greatly. In addition, a simple prototype system has been developed based on the theoretical analysis and a series of experiments have been performed under laboratory conditions to verify the system feasibility, accuracy, and stability. The experimental results demonstrate that the axial resolution in displacement measurements is better than 1 nm in a range of 200 nm which is threefold better than that can be achieved using the plane reflector.

Endocytotic potential governs magnetic particle loading in dividing neural cells: studying modes of particle inheritance

PubMed Central

Tickle, Jacqueline A; Jenkins, Stuart I; Polyak, Boris; Pickard, Mark R; Chari, Divya M

2016-01-01

Aim: To achieve high and sustained magnetic particle loading in a proliferative and endocytotically active neural transplant population (astrocytes) through tailored magnetite content in polymeric iron oxide particles. Materials & methods: MPs of varying magnetite content were applied to primary-derived rat cortical astrocytes ± static/oscillating magnetic fields to assess labeling efficiency and safety. Results: Higher magnetite content particles display high but safe accumulation in astrocytes, with longer-term label retention versus lower/no magnetite content particles. Magnetic fields enhanced loading extent. Dynamic live cell imaging of dividing labeled astrocytes demonstrated that particle distribution into daughter cells is predominantly ‘asymmetric’. Conclusion: These findings could inform protocols to achieve efficient MP loading into neural transplant cells, with significant implications for post-transplantation tracking/localization. PMID:26785794

Implicit Block ACK Scheme for IEEE 802.11 WLANs

PubMed Central

Sthapit, Pranesh; Pyun, Jae-Young

2016-01-01

The throughput of IEEE 802.11 standard is significantly bounded by the associated Medium Access Control (MAC) overhead. Because of the overhead, an upper limit exists for throughput, which is bounded, including situations where data rates are extremely high. Therefore, an overhead reduction is necessary to achieve higher throughput. The IEEE 802.11e amendment introduced the block ACK mechanism, to reduce the number of control messages in MAC. Although the block ACK scheme greatly reduces overhead, further improvements are possible. In this letter, we propose an implicit block ACK method that further reduces the overhead associated with IEEE 802.11e’s block ACK scheme. The mathematical analysis results are presented for both the original protocol and the proposed scheme. A performance improvement of greater than 10% was achieved with the proposed implementation.

Parallelism measurement for base plate of standard artifact with multiple tactile approaches

NASA Astrophysics Data System (ADS)

Ye, Xiuling; Zhao, Yan; Wang, Yiwen; Wang, Zhong; Fu, Luhua; Liu, Changjie

2018-01-01

Nowadays, as workpieces become more precise and more specialized which results in more sophisticated structures and higher accuracy for the artifacts, higher requirements have been put forward for measuring accuracy and measuring methods. As an important method to obtain the size of workpieces, coordinate measuring machine (CMM) has been widely used in many industries. In order to achieve the calibration of a self-developed CMM, it is found that the parallelism of the base plate used for fixing the standard artifact is an important factor which affects the measurement accuracy in the process of studying self-made high-precision standard artifact. And aimed to measure the parallelism of the base plate, by using the existing high-precision CMM, gauge blocks, dial gauge and marble platform with the tactile approach, three methods for parallelism measurement of workpieces are employed, and comparisons are made within the measurement results. The results of experiments show that the final accuracy of all the three methods is able to reach micron level and meets the measurement requirements. Simultaneously, these three approaches are suitable for different measurement conditions which provide a basis for rapid and high-precision measurement under different equipment conditions.

Microplastics co-gasification with biomass: Modelling syngas characteristics at low temperatures

NASA Astrophysics Data System (ADS)

Ramos, Ana; Tavares, Raquel; Rouboa, Abel

2018-05-01

To assess the syngas produced through the gasification of microplastics at low temperatures, distinct blends of polyethylene terephthalate (PET) with biomass (vine pruning) were modelled using Aspen Plus. Critical gasification parameters such as co-fuel mixture, temperature and hydrogen production were evaluated, under two different gasifier agents (air and O2). Results have shown that higher PET ratios and higher temperatures (< 1200 °C) lead to enhanced hydrogen yields, for both atmospheres. The calorific content was also seen to increase with growing temperatures, superior LHV being achieved for the mixture with less microplastics fraction (9.2 MJ/Nm3) for both air and O2 environments. A final high-quality syngas was achieved, the dominant requirement determining which parameter to optimize: on one hand, higher H2 contents were seen for the blend with higher microplastic fraction, and on the other higher LHV was achieved for the equimolar mixture.

Image reconstruction through thin scattering media by simulated annealing algorithm

NASA Astrophysics Data System (ADS)

Fang, Longjie; Zuo, Haoyi; Pang, Lin; Yang, Zuogang; Zhang, Xicheng; Zhu, Jianhua

2018-07-01

An idea for reconstructing the image of an object behind thin scattering media is proposed by phase modulation. The optimized phase mask is achieved by modulating the scattered light using simulated annealing algorithm. The correlation coefficient is exploited as a fitness function to evaluate the quality of reconstructed image. The reconstructed images optimized from simulated annealing algorithm and genetic algorithm are compared in detail. The experimental results show that our proposed method has better definition and higher speed than genetic algorithm.

Microporous Ni₁₁(HPO₃)₈(OH)₆ nanocrystals for high-performance flexible asymmetric all solid-state supercapacitors.

PubMed

Gao, Yanping; Zhao, Junhong; Run, Zhen; Zhang, Guangqin; Pang, Huan

2014-12-07

Microporous nickel phosphite [Ni11(HPO3)8(OH)6] nanocrystals were prepared using a hydrothermal method, and were successfully applied as a positive electrode in a flexible all solid-state asymmetric supercapacitor. Because of the specific micro/nanostructure, the flexible solid-state asymmetric supercapacitor can achieve a maximum energy density of 0.45 mW h cm(-3), which is higher than most reported supercapacitors. More importantly, the device performance remains efficient for 10,000 cycles.

Agile Development Methods for Space Operations

NASA Technical Reports Server (NTRS)

Trimble, Jay; Webster, Chris

2012-01-01

Main stream industry software development practice has gone from a traditional waterfall process to agile iterative development that allows for fast response to customer inputs and produces higher quality software at lower cost. How can we, the space ops community, adopt state of the art software development practice, achieve greater productivity at lower cost, and maintain safe and effective space flight operations? At NASA Ames, we are developing Mission Control Technologies Software, in collaboration with Johnson Space Center (JSC) and, more recently, the Jet Propulsion Laboratory (JPL).

"Geniuses like this are very rare today..."

NASA Astrophysics Data System (ADS)

Shcherbakov, Robert N.

2011-11-01

This paper gives insight into the context of how Lomonosov developed into a scientist and a physicist; reviews his major achievements in physics; discusses his epistemological method, and explores the major reasons for his tragedy as a physicist. The role of the poetically interpreted knowledge and science of nature in Lomonosov's popularization activities is emphasized. The paper traces Lomonosov's route from science and its popularization to the organization of higher and secondary education in Russia. How the perception of his genius changes with time is discussed.

Continuous-flow retro-Diels–Alder reaction: an efficient method for the preparation of pyrimidinone derivatives

PubMed Central

Nekkaa, Imane; Palkó, Márta; Mándity, István M

2018-01-01

The syntheses of various pyrimidinones as potentially bioactive products by means of the highly controlled continuous-flow retro-Diels–Alder reaction of condensed pyrimidinone derivatives are presented. Noteworthy, the use of this approach allowed us to rapidly screen a selection of conditions and quickly confirm the viability of preparing the desired pyrimidinones in short reaction times. Yields typically higher than those published earlier using conventional batch or microwave processes were achieved. PMID:29507637

Highly effective synthesis of a cobalt(ii) metal-organic coordination polymer by using continuous flow chemistry.

PubMed

Gong, Chunhua; Zhang, Junyong; Zeng, Xianghua; Xie, Jingli

2016-12-20

The coordination polymer [Co 2 L 4 (H 2 O) 2 ]·CH 3 CN·H 2 O (HL = (E)-2-[2-(4-chlorophenyl)vinyl]-8-hydroxyquinoline) has been achieved with 95% yield by using an Asia flow synthesis system (chip reactor). Compared with the conventional batch-type methods such as diffusion, reflux and solvothermal reactions, higher yielding reactions carried out in a flow reactor have demonstrated that this technique is a powerful strategy to obtain coordination compounds.

Sharing Leadership Responsibilities Results in Achievement Gains

ERIC Educational Resources Information Center

Armistead, Lew

2010-01-01

Collective, not individual, leadership in schools has a greater impact on student achievement; when principals and teachers share leadership responsibilities, student achievement is higher; and schools having high student achievement also display a vision for student achievement and teacher growth. Those are just a few of the insights into school…

Performance and robustness of penalized and unpenalized methods for genetic prediction of complex human disease.

PubMed

Abraham, Gad; Kowalczyk, Adam; Zobel, Justin; Inouye, Michael

2013-02-01

A central goal of medical genetics is to accurately predict complex disease from genotypes. Here, we present a comprehensive analysis of simulated and real data using lasso and elastic-net penalized support-vector machine models, a mixed-effects linear model, a polygenic score, and unpenalized logistic regression. In simulation, the sparse penalized models achieved lower false-positive rates and higher precision than the other methods for detecting causal SNPs. The common practice of prefiltering SNP lists for subsequent penalized modeling was examined and shown to substantially reduce the ability to recover the causal SNPs. Using genome-wide SNP profiles across eight complex diseases within cross-validation, lasso and elastic-net models achieved substantially better predictive ability in celiac disease, type 1 diabetes, and Crohn's disease, and had equivalent predictive ability in the rest, with the results in celiac disease strongly replicating between independent datasets. We investigated the effect of linkage disequilibrium on the predictive models, showing that the penalized methods leverage this information to their advantage, compared with methods that assume SNP independence. Our findings show that sparse penalized approaches are robust across different disease architectures, producing as good as or better phenotype predictions and variance explained. This has fundamental ramifications for the selection and future development of methods to genetically predict human disease. © 2012 WILEY PERIODICALS, INC.

Achievement motivation and memory: achievement goals differentially influence immediate and delayed remember-know recognition memory.

PubMed

Murayama, Kou; Elliot, Andrew J

2011-10-01

Little research has been conducted on achievement motivation and memory and, more specifically, on achievement goals and memory. In the present research, the authors conducted two experiments designed to examine the influence of mastery-approach and performance-approach goals on immediate and delayed remember-know recognition memory. The experiments revealed differential effects for achievement goals over time: Performance-approach goals showed higher correct remember responding on an immediate recognition test, whereas mastery-approach goals showed higher correct remember responding on a delayed recognition test. Achievement goals had no influence on overall recognition memory and no consistent influence on know responding across experiments. These findings indicate that it is important to consider quality, not just quantity, in both motivation and memory, when studying relations between these constructs.

Academic Self-Concept, Achievement Goals, and Achievement: Is Their Relation the Same for Academic Achievers and Underachievers?

ERIC Educational Resources Information Center

Preckel, Franzis; Brunner, Martin

2015-01-01

This longitudinal study investigated the contribution of achievement goals and academic self-concept for the prediction of unexpected academic achievement (i.e., achievement that is higher or lower than expected with respect to students' cognitive ability) in general and when comparing groups of extreme over- and underachievers. Our sample…

Multilaboratory evaluation of methods for detecting enteric viruses in soils.

PubMed Central

Hurst, C J; Schaub, S A; Sobsey, M D; Farrah, S R; Gerba, C P; Rose, J B; Goyal, S M; Larkin, E P; Sullivan, R; Tierney, J T

1991-01-01

Two candidate methods for the recovery and detection of viruses in soil were subjected to round robin comparative testing by members of the American Society for Testing and Materials D19:24:04:04 Subcommittee Task Group. Selection of the methods, designated "Berg" and "Goyal," was based on results of an initial screening which indicated that both met basic criteria considered essential by the task group. Both methods utilized beef extract solutions to achieve desorption and recovery of viruses from representative soils: a fine sand soil, an organic muck soil, a sandy loam soil, and a clay loam soil. One of the two methods, Goyal, also used a secondary concentration of resulting soil eluants via low-pH organic flocculation to achieve a smaller final assay volume. Evaluation of the two methods was simultaneously performed in replicate by nine different laboratories. Each of the produced samples was divided into portions, and these were respectively subjected to quantitative viral plaque assay by both the individual, termed independent, laboratory which had done the soil processing and a single common reference laboratory, using a single cell line and passage level. The Berg method seemed to produce slightly higher virus recovery values; however, the differences in virus assay titers for samples produced by the two methods were not statistically significant (P less than or equal to 0.05) for any one of the four soils. Despite this lack of a method effect, there was a statistically significant laboratory effect exhibited by assay titers from the independent versus reference laboratories for two of the soils, sandy loam and clay loam. PMID:1849712

Multilaboratory evaluation of methods for detecting enteric viruses in soils.

PubMed

Hurst, C J; Schaub, S A; Sobsey, M D; Farrah, S R; Gerba, C P; Rose, J B; Goyal, S M; Larkin, E P; Sullivan, R; Tierney, J T

1991-02-01

Two candidate methods for the recovery and detection of viruses in soil were subjected to round robin comparative testing by members of the American Society for Testing and Materials D19:24:04:04 Subcommittee Task Group. Selection of the methods, designated "Berg" and "Goyal," was based on results of an initial screening which indicated that both met basic criteria considered essential by the task group. Both methods utilized beef extract solutions to achieve desorption and recovery of viruses from representative soils: a fine sand soil, an organic muck soil, a sandy loam soil, and a clay loam soil. One of the two methods, Goyal, also used a secondary concentration of resulting soil eluants via low-pH organic flocculation to achieve a smaller final assay volume. Evaluation of the two methods was simultaneously performed in replicate by nine different laboratories. Each of the produced samples was divided into portions, and these were respectively subjected to quantitative viral plaque assay by both the individual, termed independent, laboratory which had done the soil processing and a single common reference laboratory, using a single cell line and passage level. The Berg method seemed to produce slightly higher virus recovery values; however, the differences in virus assay titers for samples produced by the two methods were not statistically significant (P less than or equal to 0.05) for any one of the four soils. Despite this lack of a method effect, there was a statistically significant laboratory effect exhibited by assay titers from the independent versus reference laboratories for two of the soils, sandy loam and clay loam.

Relationship Between Attainment of Recommended Physical Activity Guidelines and Academic Achievement: Undergraduate Students in Egypt

PubMed Central

Ansari, Walid El; Stock, Christiane

2014-01-01

Introduction: We assessed and compared by gender, students’ achievement of recommended guidelines of four PA forms, and the association between guideline achievement of each of the four PA forms and students’ academic performance. Methods: Data (2009-2010) comprised 3,271 students (11 faculties) at Assiut University, Egypt. A self-administered questionnaire measured: moderate PA (MPA), vigorous PA (VPA), moderate to vigorous PA (MVPA), muscle-strengthening PA; five socio-demographic variables (gender, age, year of study, father’s education, living arrangements during semester); self-rated health; and, academic performance. We compared the levels of four PA forms, socio-demographic variables, and academic performance by gender. Binary logistic regression examined the factors associated with achieving the guidelines of the four PA forms. Linear regression examined the association between frequency of four PA forms and level of academic performance. Results: Nearly equal proportions of males and females (37%, 36%) achieved the MPA guidelines. Significantly more males achieved the VPA, MVPA, and muscle strengthening PA guidelines. Father’s education was positively associated with achieving all four PA guidelines (with each increasing educational achievement of the father, student’s odds of achieving PA guidelines increased by 7-9%). Students living with their parents or room mates off campus were more likely to achieve the VPA and MVPA guidelines. Students who achieved VPA and MVPA guidelines were more likely to report better academic performance. For all PA forms (except MPA), increasing academic achievement was positively associated with increasing frequency of PA, but standardised Beta (0.05-0.07) suggested a modest correlation between academic achievement and PA frequency. Conclusion: The linear association between frequency of PA and academic achievement, and the finding that the proportions of students who achieved the recommended levels of several forms of PA were below half of the sample call for higher engagement of universities in fostering PA and active lifestyle among students. PMID:25169005

Analysis of Sampling Methodologies for Noise Pollution Assessment and the Impact on the Population.

PubMed

Rey Gozalo, Guillermo; Barrigón Morillas, Juan Miguel

2016-05-11

Today, noise pollution is an increasing environmental stressor. Noise maps are recognised as the main tool for assessing and managing environmental noise, but their accuracy largely depends on the sampling method used. The sampling methods most commonly used by different researchers (grid, legislative road types and categorisation methods) were analysed and compared using the city of Talca (Chile) as a test case. The results show that the stratification of sound values in road categories has a significantly lower prediction error and a higher capacity for discrimination and prediction than in the legislative road types used by the Ministry of Transport and Telecommunications in Chile. Also, the use of one or another method implies significant differences in the assessment of population exposure to noise pollution. Thus, the selection of a suitable method for performing noise maps through measurements is essential to achieve an accurate assessment of the impact of noise pollution on the population.

Fabrication and dispersion evaluation of single-wall carbon nanotubes produced by FH-arc discharge method.

PubMed

Chen, B; Zhao, X; Inoue, S; Ando, Y

2010-06-01

In this work, we produced SWNTs by a hydrogen DC arc discharge with evaporation of carbon anode containing 1 at% Fe catalyst in H2-Ar mixture gas. This was named as FH-arc discharge method. The as-grown SWNTs synthesized by FH-arc discharge method have high crystallinity. An oxidation purification process of as-grown SWNTs with H2O2 has been developed to remove the coexisting Fe catalyst nanoparticles. As a result, SWNTs with purity higher than 90 at% have been achieved. To exhibit remarkable characteristics, CNTs should be separated from the bundles and kept in homogeneous and stable suspensions. For this purpose, the SWNTs prepared by FH-arc discharge method also have been treated by Nanomizer process with some surfactants. SPM images showed that the SWNTs bundles had become thinner and shorter.

Efficient model checking of network authentication protocol based on SPIN

NASA Astrophysics Data System (ADS)

Tan, Zhi-hua; Zhang, Da-fang; Miao, Li; Zhao, Dan

2013-03-01

Model checking is a very useful technique for verifying the network authentication protocols. In order to improve the efficiency of modeling and verification on the protocols with the model checking technology, this paper first proposes a universal formalization description method of the protocol. Combined with the model checker SPIN, the method can expediently verify the properties of the protocol. By some modeling simplified strategies, this paper can model several protocols efficiently, and reduce the states space of the model. Compared with the previous literature, this paper achieves higher degree of automation, and better efficiency of verification. Finally based on the method described in the paper, we model and verify the Privacy and Key Management (PKM) authentication protocol. The experimental results show that the method of model checking is effective, which is useful for the other authentication protocols.

On modelling three-dimensional piezoelectric smart structures with boundary spectral element method

NASA Astrophysics Data System (ADS)

Zou, Fangxin; Aliabadi, M. H.

2017-05-01

The computational efficiency of the boundary element method in elastodynamic analysis can be significantly improved by employing high-order spectral elements for boundary discretisation. In this work, for the first time, the so-called boundary spectral element method is utilised to formulate the piezoelectric smart structures that are widely used in structural health monitoring (SHM) applications. The resultant boundary spectral element formulation has been validated by the finite element method (FEM) and physical experiments. The new formulation has demonstrated a lower demand on computational resources and a higher numerical stability than commercial FEM packages. Comparing to the conventional boundary element formulation, a significant reduction in computational expenses has been achieved. In summary, the boundary spectral element formulation presented in this paper provides a highly efficient and stable mathematical tool for the development of SHM applications.

Development of a method for efficient cost-effective screening of Aspergillus niger mutants having increased production of glucoamylase.

PubMed

Zhu, Xudong; Arman, Bessembayev; Chu, Ju; Wang, Yonghong; Zhuang, Yingping

2017-05-01

To develop an efficient cost-effective screening process to improve production of glucoamylase in Aspergillus niger. The cultivation of A. niger was achieved with well-dispersed morphology in 48-deep-well microtiter plates, which increased the throughput of the samples compared to traditional flask cultivation. There was a close negative correlation between glucoamylase and its pH of the fermentation broth. A novel high-throughput analysis method using Methyl Orange was developed. When compared to the conventional analysis method using 4-nitrophenyl α-D-glucopyranoside as substrate, a correlation coefficient of 0.96 by statistical analysis was obtained. Using this novel screening method, we acquired a strain with an activity of 2.2 × 10 3  U ml -1 , a 70% higher yield of glucoamylase than its parent strain.

Associations between children's intelligence and academic achievement: the role of sleep.

PubMed

Erath, Stephen A; Tu, Kelly M; Buckhalt, Joseph A; El-Sheikh, Mona

2015-10-01

Sleep problems (long wake episodes, low sleep efficiency) were examined as moderators of the relation between children's intelligence and academic achievement. The sample was comprised of 280 children (55% boys; 63% European Americans, 37% African Americans; mean age = 10.40 years, SD = 0.65). Sleep was assessed during seven consecutive nights of actigraphy. Children's performance on standardized tests of intelligence (Brief Intellectual Ability index of the Woodcock-Johnson III) and academic achievement (Alabama Reading and Math Test) were obtained. Age, sex, ethnicity, income-to-needs ratio, single parent status, standardized body mass index, chronic illness and pubertal development were controlled in analyses. Higher intelligence was strongly associated with higher academic achievement across a wide range of sleep quality. However, the association between intelligence and academic achievement was slightly attenuated among children with more long wake episodes or lower sleep efficiency compared with children with higher-quality sleep. © 2015 European Sleep Research Society.

Differential Peer Effects, Student Achievement, and Student Absenteeism: Evidence From a Large-Scale Randomized Experiment.

PubMed

Eren, Ozkan

2017-04-01

Using data from a well-executed randomized experiment, I examine the effects of gender composition and peer achievement on high school students' outcomes in disadvantaged neighborhoods. Results show that having a higher proportion of female peers in the classroom improves girls' math test scores only in less-advanced courses. For male students, the estimated gender peer effects are positive but less precisely estimated. I also find no effect of average classroom achievement on female math test scores. Males, on the other hand, seem to benefit from a higher-achieving classroom. I propose mechanisms relating to lower gender stereotype influences and gender-specific attitudes toward competition as potential explanations for peer effects findings. Finally, having a higher proportion of female students in the classroom decreases student absenteeism among male students but has no impact on female attendance.

Feasibility of Higher-Order Differential Ion Mobility Separations Using New Asymmetric Waveforms

PubMed Central

Shvartsburg, Alexandre A.; Mashkevich, Stefan V.; Smith, Richard D.

2011-01-01

Technologies for separating and characterizing ions based on their transport properties in gases have been around for three decades. The early method of ion mobility spectrometry (IMS) distinguished ions by absolute mobility that depends on the collision cross section with buffer gas atoms. The more recent technique of field asymmetric waveform IMS (FAIMS) measures the difference between mobilities at high and low electric fields. Coupling IMS and FAIMS to soft ionization sources and mass spectrometry (MS) has greatly expanded their utility, enabling new applications in biomedical and nanomaterials research. Here, we show that time-dependent electric fields comprising more than two intensity levels could, in principle, effect an infinite number of distinct differential separations based on the higher-order terms of expression for ion mobility. These analyses could employ the hardware and operational procedures similar to those utilized in FAIMS. Methods up to the 4th or 5th order (where conventional IMS is 1st order and FAIMS is 2nd order) should be practical at field intensities accessible in ambient air, with still higher orders potentially achievable in insulating gases. Available experimental data suggest that higher-order separations should be largely orthogonal to each other and to FAIMS, IMS, and MS. PMID:16494377

Speckle reduction in optical coherence tomography using two-step iteration method (Conference Presentation)

NASA Astrophysics Data System (ADS)

Wang, Xianghong; Liu, Xinyu; Wang, Nanshuo; Yu, Xiaojun; Bo, En; Chen, Si; Liu, Linbo

2017-02-01

Optical coherence tomography (OCT) provides high resolution and cross-sectional images of biological tissue and is widely used for diagnosis of ocular diseases. However, OCT images suffer from speckle noise, which typically considered as multiplicative noise in nature, reducing the image resolution and contrast. In this study, we propose a two-step iteration (TSI) method to suppress those noises. We first utilize augmented Lagrange method to recover a low-rank OCT image and remove additive Gaussian noise, and then employ the simple and efficient split Bregman method to solve the Total-Variation Denoising model. We validated such proposed method using images of swine, rabbit and human retina. Results demonstrate that our TSI method outperforms the other popular methods in achieving higher peak signal-to-noise ratio (PSNR) and structure similarity (SSIM) while preserving important structural details, such as tiny capillaries and thin layers in retinal OCT images. In addition, the results of our TSI method show clearer boundaries and maintains high image contrast, which facilitates better image interpretations and analyses.

Discontinuation of tofacitinib after achieving low disease activity in patients with rheumatoid arthritis: a multicentre, observational study.

PubMed

Kubo, Satoshi; Yamaoka, Kunihiro; Amano, Koichi; Nagano, Shuji; Tohma, Shigeto; Suematsu, Eiichi; Nagasawa, Hayato; Iwata, Kanako; Tanaka, Yoshiya

2017-08-01

To determine whether tofacitinib can be discontinued in patients with RA who achieve low disease activity (LDA). RA patients with LDA after tofacitinib treatment in a phase III and long-term extension study were enrolled in this multicentre, non-randomized, open, prospective, observational study. The decision of discontinuation or continuation of tofacitinib was determined based on patient-physician decision making with informed consent. The primary endpoint was the proportion of patients who remained tofacitinib-free at post-treatment week 52. Clinical outcome was compared between those who continued and those who discontinued tofacitinib. The last observation carried forward method was used for patients who could not discontinue tofacitinib before week 52. Of 64 patients, 54 discontinued and 10 continued tofacitinib therapy. At post-treatment week 52, 20 of the 54 patients (37%) of the discontinuation group remained tofacitinib-free without disease flare. Disease activity at post-treatment week 52 was higher in the discontinuation group than the continuation group. Among the discontinuation group, the RF titre at baseline was significantly lower in patients who remained tofacitinib-free than those who did not (40 vs 113 U/ml). In fact, a higher proportion of patients with lower RF remained tofacitinib-free at week 52 compared with those with higher RF at baseline. In patients who could not achieve tofacitinib-free status, re-initiation of tofacitinib or other biologics improved disease activity. It is possible to discontinue tofacitinib without flare in about a third of patients with RA. A low RF predicts maintenance of LDA after discontinuation of tofacitinib. © The Author 2017. Published by Oxford University Press on behalf of the British Society for Rheumatology. All rights reserved. For Permissions, please email: journals.permissions@oup.com

A Phase II Trial of Docetaxel with Rapid Androgen Cycling as a Treatment for Patients with Prostate Cancer

PubMed Central

Rathkopf, Dana; Carducci, Michael A.; Morris, Michael J.; Slovin, Susan F.; Eisenberger, Mario A.; Pili, Roberto; Denmeade, Samuel R.; Kelsen, Moshe; Curley, Tracy; Priet, Regina; Collins, Connie; Fleisher, Martin; Heller, Glenn; Baker, Sharyn D.; Scher, Howard I.

2011-01-01

Purpose We evaluated rapid androgen cycling in combination with docetaxel for men with progressive non-castrate prostate cancers. Methods Non-castrate patients with ≤ 6 months of hormones were eligible. Cohort 1 (63 patients ) received 6 28-day cycles of docetaxel (75 mg/m2), leuprolide and 7 days of topical testosterone. Cohort 2 (39 patients) received 9 21-day cycles of docetaxel (70 mg/m2), leuprolide and 3 days of testosterone. The primary endpoint was the proportion of patients at 18 months who achieved non -castrate testosterone levels (>150 ng/dl) and an undetectable PSA (≤ 0.05, ≤0.5, or ≤2.0 ng/ml with prior prostatectomy, radiotherapy, or no definitive therapy, respectively). Cytochrome P450 3A4 (CYP3A4) activity and docetaxel pharmacokinetics were evaluated. Results A higher proportion of patients achieved the undetectable PSA outcome at 18 months in cohort 2 relative to cohort 1 (13% vs. 0%). The 16% incidence of febrile neutropenia was higher than observed in patients was castration-resistant disease, which may have been related to a 50% reduction in overall docetaxel clearance in the non-castrate group. There was no alteration in CYP3A4 activity (P=0.87) or docetaxel clearance (P=0.88) between cycles. Conclusions The undetectable PSA endpoint allows for a rapid screening of interventions for further study. Increasing the number of docetaxel cycles following a shorter period of testosterone repletion, and a longer duration of testosterone depletion, increased the proportion of men who achieved an undetectable PSA. The higher-than-expected incidence of febrile neutropenia may have been related to the reduced overall docetaxel clearance in patients with non-castrate vs castrate testosterone levels. PMID:18565882

Effects of wavelength and water quality on photodegradation of N-Nitrosodimethylamine (NDMA).

PubMed

Sakai, Hiroshi; Takamatsu, Tatsuro; Kosaka, Koji; Kamiko, Naoyuki; Takizawa, Satoshi

2012-10-01

N-Nitrosodimethylamine (NDMA) is a potent carcinogen that yields a cancer risk of 10(-6) at concentrations as low as 0.7 ng L(-1). Tentative guideline values are set at 3 ng L(-1) in California, USA; 9 ng L(-1) in Ontario, Canada; 40 ng L(-1) nationwide in Canada; and 100 ng L(-1) by the World Health Organization. NDMA is a great concern in treating reclaimed water as well as drinking water. UV degradation can be considered effective degradation method. A 1-log reduction of NDMA is achieved by 1000 mJ cm(-2) of a 254-nm low pressure (LP) mercury UV lamp. However, a higher degradation efficiency than that provided by LP lamps is desired in practical treatment. In this study, the effects of wavelength and water quality were investigated to achieve higher degradation efficiency. The effects of wavelength were examined by comparing three UV lamps: a 222-nm Kr Cl Excimer UV lamp, a 254-nm LP mercury UV lamp, and a 230- to 270-nm filtered medium pressure (FMP) mercury UV lamp. The 222-nm lamp and FMP lamp achieved 4 times and 2.8 times higher degradation efficiency, respectively, than the conventional 254-nm LP lamp. Effects on water quality were also simulated by using absorption spectrum data of nitrate solutions and process water from a drinking-water treatment plant. In the simulation, the 222-nm lamp was affected by UV-absorbing compounds in the water, whereas the FMP lamp showed more stable degradation efficiency. Appropriate use of these three types of lamps could enhance the efficiency of degradation of NDMA. Copyright © 2012 Elsevier Ltd. All rights reserved.

Study of structural properties of cubic InN films on GaAs(001) substrates by molecular beam epitaxy and migration enhanced epitaxy

DOE Office of Scientific and Technical Information (OSTI.GOV)

Casallas-Moreno, Y. L.; Perez-Caro, M.; Gallardo-Hernandez, S.

InN epitaxial films with cubic phase were grown by rf-plasma-assisted molecular beam epitaxy (RF-MBE) on GaAs(001) substrates employing two methods: migration-enhanced epitaxy (MEE) and conventional MBE technique. The films were synthesized at different growth temperatures ranging from 490 to 550 Degree-Sign C, and different In beam fluxes (BEP{sub In}) ranging from 5.9 Multiplication-Sign 10{sup -7} to 9.7 Multiplication-Sign 10{sup -7} Torr. We found the optimum conditions for the nucleation of the cubic phase of the InN using a buffer composed of several thin layers, according to reflection high-energy electron diffraction (RHEED) patterns. Crystallographic analysis by high resolution X-ray diffraction (HR-XRD)more » and RHEED confirmed the growth of c-InN by the two methods. We achieved with the MEE method a higher crystal quality and higher cubic phase purity. The ratio of cubic to hexagonal components in InN films was estimated from the ratio of the integrated X-ray diffraction intensities of the cubic (002) and hexagonal (1011) planes measured by X-ray reciprocal space mapping (RSM). For MEE samples, the cubic phase of InN increases employing higher In beam fluxes and higher growth temperatures. We have obtained a cubic purity phase of 96.4% for a film grown at 510 Degree-Sign C by MEE.« less

Learning science in a cooperative setting: Academic achievement and affective outcomes

NASA Astrophysics Data System (ADS)

Lazarowitz, Reuven; Hertz-Lazarowitz, Rachel; Baird, J. Hugh

A learning unit in earth science was taught to high school students, using a jigsaw-group mastery learning approach. The sample consisted of 73 students in the experimental group and 47 students who learned the topic in an individualized mastery learning approach. The study lasted 5 weeks. Pretests and posttests on academic achievement and affective outcomes were administered. Data were treated with an analysis of covariance. The results show that students of the experimental group achieved significantly higher on academic outcomes, both normative and objective scores. On the creative essay test, the differences in number of ideas and total essay score were not significant between the groups, although the mean scores for number of words were higher for the individualized mastery learning group. On the affective domain, jigsaw-group mastery learning students scored significantly higher on self-esteem, number of friends, and involvement in the classroom. No differences were found in cohesiveness, cooperation, competition, and attitudes toward the subject learned. The results are discussed through the evaluation and comparison of the two methods of instruction used in this study.The cooperative learning movement began in junior high schools as part of the desegregation process, aiming at facilitating positive ethnic relations and increasing academic achievement and social skills among diverse students (Aronson, Stephan, Sikes, Blaney, & Snapp, 1978; Sharan & Hertz-Lazarowitz, 1980; Slavin, 1980). However, elementary teachers quickly recognized the potential of cooperative methods, and such methods were adopted freely in elementary schools before becoming widespread on the junior and senior high level. It has only been during the past few years that application of cooperative learning has been studied extensively with these older students.Cooperative learning methods generally involve heterogeneous groups working together on tasks that are deliberately structured to provide specific assignments and individual contributions from each group member. Cognitive as well as social benefits are expected, as students clarify their own understanding and share their insights and ideas with each other as they interact within the group (Deutsch, 1949).Experiments in the science laboratory have always required students to work in groups of two to four, due to the constraints of experimental processes and limited equipment and sup- plies. Thus, science courses are a natural curriculum area for examining cooperative learning practices. Now that cooperative methods are being refined to develop particular capabilities in the students, science teachers need to examine ways of structuring specific tasks to achieve the academic, affective, and socialization goals for their students. Although most of the studies of cooperative learning in the high school science classroom have centered around the cognitive outcomes of achievement testing and process skills, affective and social outcomes are also significant with students of this age. But few studies in science classes have attempted to assess such aspects of students' progress.As part of a previous revision, the science faculty at the high school where this study was conducted developed an exemplary individualized mastery learning (1ML) program for teaching science. This program seemed to alleviate the severe motivational problems and the extreme individual differences among the students in this rural/bhe-collar community. Students learned to work independently on their science studies. They had almost no lectures and few large group activities. As they worked through their assignments, however, they were free to interdct with other students. Looking in on a typical class, one would see several clusters of two or three students working together, sometimes tutoring each other, sometimes just talking through an assignment. Yet at least half of the class members would be working all alone. The importance of the overall social setting in the classroom as it relates to learning (Bruner, 1986, p. 86) and the central function of social interaction as learning occurs (Vygotsky, 1978, p. 106) seemed to have been ignored. Therefore, group mastery learning (GML), a cooperative learning tech- nique, was suggested as an antithesis to IML for teaching science over short periods. The cooperative mode of instruction considers learning as a cognitive as well as a social process, where students interact with each other as well as the teacher.To bring the social dimension back to science classrooms, the researchers chose to imple- ment GML in Grades 1 I and 12. The goal of the study was to investigate the GML's impact of the method on the individual student's academic achievement, creativity, self-esteem, and number of friends and on the overall learning environment of the classrooms. The researchers were also concerned with the students' attitudes toward earth science, the course being taught at the time of the experiment. Both cognitive and affective outcomes for students who participated in the cooperative GML approach were compared with outcomes for students who studied the same topic in an IML approach.The study addressed a number of questions related to academic and nonacademic outcomes of the two methods of study. First, it sought to determine whether academic achievement of the students taught in the cooperative GML mode would be different from the achievement of students who learned in an individualized method. Second, it sought to determine whether gains or losses would be seen in nonacademic outcomes, such as classroom learning environment, social relations, and students' self-esteem experienced by the students. The results of this study may support more use of cooperative learning in high school science.

Family, school, and community factors and relationships to racial-ethnic attitudes and academic achievement.

PubMed

Smith, Emilie Phillips; Atkins, Jacqueline; Connell, Christian M

2003-09-01

This study examined family, school, and community factors and the relationships to racial-ethnic attitudes and academic achievement among 98 African American fourth-grade children. It has been posited that young people who feel better about their racial-ethnic background have better behavioral and academic outcomes, yet there is a need for more empirical tests of this premise. Psychometric information is reported on measures of parent, teacher, and child racial-ethnic attitudes. Path analysis was used to investigate ecological variables potentially related to children's racial-ethnic attitudes and achievement. Parental education and level of racial-ethnic pride were correlated and both were related to children's achievement though in the final path model, only the path from parental education level was statistically significant. Children whose teachers exhibited higher levels of racial-ethnic trust and perceived fewer barriers due to race and ethnicity evidenced more trust and optimism as well. Children living in communities with higher proportions of college-educated residents also exhibited more positive racial-ethnic attitudes. For children, higher racial-ethnic pride was related to higher achievement measured by grades and standardized test scores, while racial distrust and perception of barriers due to race were related to reduced performance. This study suggests that family, school, and community are all important factors related to children's racial-ethnic attitudes and also to their academic achievement.

Approach for discrimination and quantification of electroactive species: kinetics difference revealed by higher harmonics of Fourier transformed sinusoidal voltammetry.

PubMed

Fang, Yishan; Huang, Xinjian; Wang, Lishi

2015-01-06

Discrimination and quantification of electroactive species are traditionally realized by a potential difference which is mainly determined by thermodynamics. However, the resolution of this approach is limited to tens of millivolts. In this paper, we described an application of Fourier transformed sinusoidal voltammetry (FT-SV) that provides a new approach for discrimination and quantitative evaluation of electroactive species, especially thermodynamic similar ones. Numerical simulation indicates that electron transfer kinetics difference between electroactive species can be revealed by the phase angle of higher order harmonics of FT-SV, and the difference can be amplified order by order. Thus, even a very subtle kinetics difference can be amplified to be distinguishable at a certain order of harmonics. This method was verified with structurally similar ferrocene derivatives which were chosen as the model systems. Although these molecules have very close redox potential (<10 mV), discrimination and selective detection were achieved by as high as the thirteenth harmonics. The results demonstrated the feasibility and reliability of the method. It was also implied that the combination of the traditional thermodynamic method and this kinetics method can form a two-dimension resolved detection method, and it has the potential to extend the resolution of voltammetric techniques to a new level.

Alternative evaluation metrics for risk adjustment methods.

PubMed

Park, Sungchul; Basu, Anirban

2018-06-01

Risk adjustment is instituted to counter risk selection by accurately equating payments with expected expenditures. Traditional risk-adjustment methods are designed to estimate accurate payments at the group level. However, this generates residual risks at the individual level, especially for high-expenditure individuals, thereby inducing health plans to avoid those with high residual risks. To identify an optimal risk-adjustment method, we perform a comprehensive comparison of prediction accuracies at the group level, at the tail distributions, and at the individual level across 19 estimators: 9 parametric regression, 7 machine learning, and 3 distributional estimators. Using the 2013-2014 MarketScan database, we find that no one estimator performs best in all prediction accuracies. Generally, machine learning and distribution-based estimators achieve higher group-level prediction accuracy than parametric regression estimators. However, parametric regression estimators show higher tail distribution prediction accuracy and individual-level prediction accuracy, especially at the tails of the distribution. This suggests that there is a trade-off in selecting an appropriate risk-adjustment method between estimating accurate payments at the group level and lower residual risks at the individual level. Our results indicate that an optimal method cannot be determined solely on the basis of statistical metrics but rather needs to account for simulating plans' risk selective behaviors. Copyright © 2018 John Wiley & Sons, Ltd.

Research on the shortwave infrared hyperspectral imaging technology based on Integrated Stepwise filter

NASA Astrophysics Data System (ADS)

Wei, Liqing; Xiao, Xizhong; Wang, Yueming; Zhuang, Xiaoqiong; Wang, Jianyu

2017-11-01

Space-borne hyperspectral imagery is an important tool for earth sciences and industrial applications. Higher spatial and spectral resolutions have been sought persistently, although this results in more power, larger volume and weight during a space-borne spectral imager design. For miniaturization of hyperspectral imager and optimization of spectral splitting methods, several methods are compared in this paper. Spectral time delay integration (TDI) method with high transmittance Integrated Stepwise Filter (ISF) is proposed.With the method, an ISF imaging spectrometer with TDI could achieve higher system sensitivity than the traditional prism/grating imaging spectrometer. In addition, the ISF imaging spectrometer performs well in suppressing infrared background radiation produced by instrument. A compact shortwave infrared (SWIR) hyperspectral imager prototype based on HgCdTe covering the spectral range of 2.0-2.5 μm with 6 TDI stages was designed and integrated. To investigate the performance of ISF spectrometer, a method to derive the optimal blocking band curve of the ISF is introduced, along with known error characteristics. To assess spectral performance of the ISF system, a new spectral calibration based on blackbody radiation with temperature scanning is proposed. The results of the imaging experiment showed the merits of ISF. ISF has great application prospects in the field of high sensitivity and high resolution space-borne hyperspectral imagery.

Time integration algorithms for the two-dimensional Euler equations on unstructured meshes

NASA Technical Reports Server (NTRS)

Slack, David C.; Whitaker, D. L.; Walters, Robert W.

1994-01-01

Explicit and implicit time integration algorithms for the two-dimensional Euler equations on unstructured grids are presented. Both cell-centered and cell-vertex finite volume upwind schemes utilizing Roe's approximate Riemann solver are developed. For the cell-vertex scheme, a four-stage Runge-Kutta time integration, a fourstage Runge-Kutta time integration with implicit residual averaging, a point Jacobi method, a symmetric point Gauss-Seidel method and two methods utilizing preconditioned sparse matrix solvers are presented. For the cell-centered scheme, a Runge-Kutta scheme, an implicit tridiagonal relaxation scheme modeled after line Gauss-Seidel, a fully implicit lower-upper (LU) decomposition, and a hybrid scheme utilizing both Runge-Kutta and LU methods are presented. A reverse Cuthill-McKee renumbering scheme is employed for the direct solver to decrease CPU time by reducing the fill of the Jacobian matrix. A comparison of the various time integration schemes is made for both first-order and higher order accurate solutions using several mesh sizes, higher order accuracy is achieved by using multidimensional monotone linear reconstruction procedures. The results obtained for a transonic flow over a circular arc suggest that the preconditioned sparse matrix solvers perform better than the other methods as the number of elements in the mesh increases.

The Economic Value of Higher Teacher Quality

ERIC Educational Resources Information Center

Hanushek, Eric A.

2011-01-01

Most analyses of teacher quality end without any assessment of the economic value of altered teacher quality. This paper combines information about teacher effectiveness with the economic impact of higher achievement. It begins with an overview of what is known about the relationship between teacher quality and student achievement. This provides…

Achieving Equity in Higher Education: The Unfinished Agenda

ERIC Educational Resources Information Center

Astin, Alexander W.; Astin, Helen S.

2015-01-01

In this retrospective account of their scholarly work over the past 45 years, Alexander and Helen Astin show how the struggle to achieve greater equity in American higher education is intimately connected to issues of character development, leadership, civic responsibility, and spirituality. While shedding some light on a variety of questions…

Achieving Diversity in Academia: A Dream Deferred?

ERIC Educational Resources Information Center

Leonard, Jacqueline; Horvat, Erin McNamara; Riley-Tillman, T. Chris

Attempts to achieve diversity in the faculty in institutions of higher education have increased in recent years. Despite these attempts, faculty of color and women are still underrepresented in the higher ranks. This paper presents autobiographies focusing on the career trajectories of three junior faculty members at one institution: a divorced…

Relating Aspects of Adolescent Emotional Autonomy to Academic Achievement and Deviant Behavior.

ERIC Educational Resources Information Center

Chen, Zeng-Yin; Dornbusch, Sanford M.

1998-01-01

Used a structural-equation model with latent constructs to differentiate the domains of adolescent emotional autonomy from parents and specify the intervening processes. Found that individuation was associated with lower academic achievement and higher rates of deviant behavior through the intervening effects of higher susceptibility to negative…