Jigsaw puzzle metasurface for multiple functions: polarization conversion, anomalous reflection and diffusion.

PubMed

Zhao, Yi; Cao, Xiangyu; Gao, Jun; Liu, Xiao; Li, Sijia

2016-05-16

We demonstrate a simple reconfigurable metasurface with multiple functions. Anisotropic tiles are investigated and manufactured as fundamental elements. Then, the tiles are combined in a certain sequence to construct a metasurface. Each of the tiles can be adjusted independently which is like a jigsaw puzzle and the whole metasurface can achieve diverse functions by different layouts. For demonstration purposes, we realize polarization conversion, anomalous reflection and diffusion by a jigsaw puzzle metasurface with 6 × 6 pieces of anisotropic tile. Simulated and measured results prove that our method offers a simple and effective strategy for metasurface design.

The Effect of Gender on the Achievement of Students in Biology Using the Jigsaw Method

ERIC Educational Resources Information Center

Amedu, Odagboyi Isaiah

2015-01-01

This paper examined the effect of gender on the achievement of students in biology using the jigsaw method. The sample was made up of 87 students in SS1 in a secondary school. The study utilized an intact class because the study took place in a normal school term. There were 39 males and 49 females. The Biology Achievement Test (BAT) was…

The Jigsaw Technique and Self-Efficacy of Vocational Training Students: A Practice Report

ERIC Educational Resources Information Center

Darnon, Celine; Buchs, Celine; Desbar, Delphine

2012-01-01

Can teenagers' self-efficacy be improved in a short time? Previous research has shown the positive effect of cooperative learning methods, including "jigsaw classrooms" (Aronson and Patnoe, 1997), on various outcomes (e.g., the liking of school, self-esteem, and reduction of prejudices). The present practice report investigated the effects of…

Impact of Expert Teaching Quality on Novice Academic Performance in the Jigsaw Cooperative Learning Method

ERIC Educational Resources Information Center

Berger, Roland; Hänze, Martin

2015-01-01

We assessed the impact of expert students' instructional quality on the academic performance of novice students in 12th-grade physics classes organized in an expert model of cooperative learning ("jigsaw classroom"). The instructional quality of 129 expert students was measured by a newly developed rating system. As expected, when…

Effects of Jigsaw and Animation Techniques on Students' Understanding of Concepts and Subjects in Electrochemistry

ERIC Educational Resources Information Center

Doymus, Kemal; Karacop, Ataman; Simsek, Umit

2010-01-01

This study investigated the effect of jigsaw cooperative learning and animation versus traditional teaching methods on students' understanding of electrochemistry in a first-year general chemistry course. This study was carried out in three different classes in the department of primary science education during the 2007-2008 academic year. The…

Effect of Jigsaw II, Reading-Writing-Presentation, and Computer Animations on the Teaching of "Light" Unit

ERIC Educational Resources Information Center

Koç, Yasemin; Yildiz, Emre; Çaliklar, Seyma; Simsek, Ümit

2016-01-01

The aim of this study is to determine the effect of Jigsaw II technique, reading-writing-presentation method, and computer animation on students' academic achievements, epistemological beliefs, attitudes towards science lesson, and the retention of knowledge in the "Light" unit covered in the 7th grade. The sample of the study consists…

De novo assembly and next-generation sequencing to analyse full-length gene variants from codon-barcoded libraries.

PubMed

Cho, Namjin; Hwang, Byungjin; Yoon, Jung-ki; Park, Sangun; Lee, Joongoo; Seo, Han Na; Lee, Jeewon; Huh, Sunghoon; Chung, Jinsoo; Bang, Duhee

2015-09-21

Interpreting epistatic interactions is crucial for understanding evolutionary dynamics of complex genetic systems and unveiling structure and function of genetic pathways. Although high resolution mapping of en masse variant libraries renders molecular biologists to address genotype-phenotype relationships, long-read sequencing technology remains indispensable to assess functional relationship between mutations that lie far apart. Here, we introduce JigsawSeq for multiplexed sequence identification of pooled gene variant libraries by combining a codon-based molecular barcoding strategy and de novo assembly of short-read data. We first validate JigsawSeq on small sub-pools and observed high precision and recall at various experimental settings. With extensive simulations, we then apply JigsawSeq to large-scale gene variant libraries to show that our method can be reliably scaled using next-generation sequencing. JigsawSeq may serve as a rapid screening tool for functional genomics and offer the opportunity to explore evolutionary trajectories of protein variants.

Using cooperative learning for a drug information assignment.

PubMed

Earl, Grace L

2009-11-12

To implement a cooperative learning activity to engage students in analyzing tertiary drug information resources in a literature evaluation course. The class was divided into 4 sections to form expert groups and each group researched a different set of references using the jigsaw technique. Each member of each expert group was reassigned to a jigsaw group so that each new group was composed of 4 students from 4 different expert groups. The jigsaw groups met to discuss search strategies and rate the usefulness of the references. In addition to group-based learning, teaching methods included students' writing an independent research paper to enhance their abilities to search and analyze drug information resources. The assignment and final course grades improved after implementation of the activity. Students agreed that class discussions were a useful learning experience and 75% (77/102) said they would use the drug information references for other courses. The jigsaw technique was successful in engaging students in cooperative learning to improve critical thinking skills regarding drug information.

Learning Achievement Improvement Efforts Course Learn and Learning Using the Jigsaw Method and Card Media in STKIP PGRI Ngawi 2014/2015 Academic Year

ERIC Educational Resources Information Center

Haryono

2015-01-01

Subject Teaching and Learning is a basic educational courses that must be taken by all student teachers. Class Action Research aims to improve student achievement Teaching and Learning course by applying Jigsaw and media cards. Research procedures using Classroom Action Research (CAR) with multiple cycles. Each cycle includes four phases:…

Cooperative learning in 'Special Needs in Dentistry' for undergraduate students using the Jigsaw approach.

PubMed

Suárez-Cunqueiro, M M; Gándara-Lorenzo, D; Mariño-Pérez, R; Piñeiro-Abalo, S; Pérez-López, D; Tomás, I

2017-11-01

The goals of this study were to (i) describe the use of the Jigsaw approach for the resolution of clinical cases by undergraduate students in the subject 'Special Needs in Dentistry' and (ii) assess the impact of its implementation on academic performance and the students' perception. The Jigsaw approach was applied to the fifth-year in the subject 'Special Needs in Dentistry', as part of the Dentistry degree curriculum of the University of Santiago de Compostela, during the academic years 2012/2013 and 2013/2014. A total of 109 dental students were enrolled in the study, and the final marks of the Jigsaw (n = 55) and the non-Jigsaw groups (n = 54) were compared. Students' perceptions on the Jigsaw technique were assessed using a 13-question questionnaire. Academic performance based on the final examination mark for the Jigsaw and non-Jigsaw groups was 6.45 ± 1.49 and 6.13 ± 1.50, respectively. There were not students in the Jigsaw group who failed to attend the mandatory examination (0% vs. 12.96% in the non-Jigsaw group, P = 0.006). The questionnaire's internal consistency was 0.90. The mean value for all the questionnaire items was 3.80, with the highest response score of 4.35 for the statement 'I have seen the complexity that the resolution of a clinical case can involve'. Based on the students' perceptions, the Jigsaw approach could contribute to a better understanding of the complexity of solving clinical cases in the subject 'Special Needs in Dentistry'. However, further investigations should be conducted to analyse the influence of this technique on students' academic performance in the field of clinical dentistry. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

A Jigsaw Lesson for Operations of Complex Numbers.

ERIC Educational Resources Information Center

Lucas, Carol A.

2000-01-01

Explains the cooperative learning technique of jigsaw. Details the use of a jigsaw lesson for explaining complex numbers to intermediate algebra students. Includes copies of the handouts given to the expert groups. (Author/ASK)

Jigsaw Cooperative Learning: Acid-Base Theories

ERIC Educational Resources Information Center

Tarhan, Leman; Sesen, Burcin Acar

2012-01-01

This study focused on investigating the effectiveness of jigsaw cooperative learning instruction on first-year undergraduates' understanding of acid-base theories. Undergraduates' opinions about jigsaw cooperative learning instruction were also investigated. The participants of this study were 38 first-year undergraduates in chemistry education…

Better Field Instruction by Using Jigsaw Groups

NASA Astrophysics Data System (ADS)

Sammons, J. I.; Murray, D. P.

2006-12-01

Do any of these sound familiar? Most of my students do well at field stops, but there are always the few at the back. I'd like to guest speak at the local High School, but the students have too little background. I wish I could spark the interest of my introductory classes. Jigsaw is the solution to these problems. This easy-to-apply technique puts students in the driver's seat. They make the inferences-they own the discovery. You'll see that "A-ha!" as though it were a first time event. Jigsaw brings new excitement to familiar activities for every student in your class, even that guy in the back. Best of all, the technique does not depend on the style or force of personality of the instructor. It is easy to learn and suitable for use by Teaching Assistants. Here's how it works: 1. Identify the critical concepts necessary for a full understanding of the field stop or activity. 2. Divide your class into Expert Groups. The members of each Expert Group will master one of these critical concepts. 3.Dissolve the Expert Groups. Divide your class into new Jigsaw Groups to address the field stop or activity. Each Jigsaw Group includes members from each Expert Group. Like pieces of a puzzle, each Jigsaw Group member brings a critical piece to the problem. This talk will demonstrate Jigsaw Groups in action at a field stop. You'll see the crucial identification of critical concepts, small lab explorations carried out by the Expert Groups to master their assigned concepts, and Jigsaw Groups working a complex geological feature. You'll learn how to trouble-shoot less-than-successful first attempts and you'll leave with a step-by-step template that will allow you to adapt your existing activities to Jigsaw technique.

Effects of Computer-Assisted Jigsaw II Cooperative Learning Strategy on Physics Achievement and Retention

ERIC Educational Resources Information Center

Gambari, Isiaka Amosa; Yusuf, Mudasiru Olalere

2016-01-01

This study investigated the effects of computer-assisted Jigsaw II cooperative strategy on physics achievement and retention. The study also determined how moderating variables of achievement levels as it affects students' performance in physics when Jigsaw II cooperative learning is used as an instructional strategy. Purposive sampling technique…

Put Students in Charge: A Variation on the Jigsaw Discussion

ERIC Educational Resources Information Center

Benton, Raymond, Jr.

2016-01-01

In this article Raymond Benton, Jr. describes how he implemented a variation on Eliot Aronson's (Aronson et al. 1978) "jigsaw classroom" activity. While there are similarities between Aronson's jigsaw classroom and what is described here, there are differences as well. In Aronson's system, the classroom was divided into subgroups. Each…

Jigsaw Variations and Attitudes about Learning and the Self in Cognitive Psychology

ERIC Educational Resources Information Center

Crone, Travis S.; Portillo, Mary C.

2013-01-01

Jigsaw classroom research has primarily explored racial relationships at the primary and secondary educational levels. The present study explored whether the jigsaw classroom would have an effect on students' attitudes about their own academic abilities and practices at the university level. The present study also sought to illuminate the…

Robust Sex Differences in Jigsaw Puzzle Solving—Are Boys Really Better in Most Visuospatial Tasks?

PubMed Central

Kocijan, Vid; Horvat, Marina; Majdic, Gregor

2017-01-01

Sex differences are consistently reported in different visuospatial tasks with men usually performing better in mental rotation tests while women are better on tests for memory of object locations. In the present study, we investigated sex differences in solving jigsaw puzzles in children. In total 22 boys and 24 girls were tested using custom build tablet application representing a jigsaw puzzle consisting of 25 pieces and featuring three different pictures. Girls outperformed boys in solving jigsaw puzzles regardless of the picture. Girls were faster than boys in solving the puzzle, made less incorrect moves with the pieces of the puzzle, and spent less time moving the pieces around the tablet. It appears that the strategy of solving the jigsaw puzzle was the main factor affecting differences in success, as girls tend to solve the puzzle more systematically while boys performed more trial and error attempts, thus having more incorrect moves with the puzzle pieces. Results of this study suggest a very robust sex difference in solving the jigsaw puzzle with girls outperforming boys by a large margin. PMID:29109682

Robust Sex Differences in Jigsaw Puzzle Solving-Are Boys Really Better in Most Visuospatial Tasks?

PubMed

Kocijan, Vid; Horvat, Marina; Majdic, Gregor

2017-01-01

Sex differences are consistently reported in different visuospatial tasks with men usually performing better in mental rotation tests while women are better on tests for memory of object locations. In the present study, we investigated sex differences in solving jigsaw puzzles in children. In total 22 boys and 24 girls were tested using custom build tablet application representing a jigsaw puzzle consisting of 25 pieces and featuring three different pictures. Girls outperformed boys in solving jigsaw puzzles regardless of the picture. Girls were faster than boys in solving the puzzle, made less incorrect moves with the pieces of the puzzle, and spent less time moving the pieces around the tablet. It appears that the strategy of solving the jigsaw puzzle was the main factor affecting differences in success, as girls tend to solve the puzzle more systematically while boys performed more trial and error attempts, thus having more incorrect moves with the puzzle pieces. Results of this study suggest a very robust sex difference in solving the jigsaw puzzle with girls outperforming boys by a large margin.

Understanding the Carbon Cycle : A Jigsaw Approach

NASA Astrophysics Data System (ADS)

Hastings, D. W.

2006-12-01

A thorough understanding of the carbon cycle is fundamental to understanding the eventual fate of CO2. To achieve this, students must understand individual processes, such as photosynthesis and respiration, as well as an integrated knowledge of how these processes relate to each other. In this "jigsaw" exercise, each student is assigned one five fundamental geochemical processes in the short- term carbon cycle to research and fully understand. In class, students first meet with others who have studied the same process to strengthen and deepen their understanding of this process. They then form teams of five students and explain to other students their particular process. In exchange, other students explain the other aspects of the carbon cycle. At the end of class all students will know about each of the five processes, and thus develop an integrated understanding of the entire carbon cycle. This approach is an efficient method for students to learn the material. As in a jigsaw puzzle, each student's part is essential for the full understanding of the carbon cycle. Since each student's part is essential, then each student is essential, which is what makes this strategy effective The jigsaw approach encourages listening, engagement, and collaboration by giving each member of the group an essential part to play in the academic activity.

Strategies and Correlates of Jigsaw Puzzle and Visuospatial Performance by Persons with Prader-Willi Syndrome

ERIC Educational Resources Information Center

Verdine, Brian N.; Troseth, Georgene L.; Hodapp, Robert M.; Dykens, Elisabeth M.

2008-01-01

Some individuals with Prader-Willi syndrome exhibit strengths in solving jigsaw puzzles. We compared visuospatial ability and jigsaw puzzle performance and strategies of 26 persons with Prader-Willi syndrome and 26 MA-matched typically developing controls. Individuals with Prader-Willi syndrome relied on piece shape. Those in the control group…

Explorers, Detectives, Matchmakers, and Lion Tamers: Understanding Jigsaw Puzzlers' Techniques and Motivations

ERIC Educational Resources Information Center

Garcia, Angela Cora

2013-01-01

Why do people enjoy jigsaw puzzles, which--challenging and time-consuming as they are--might be considered more like work than play? The author investigates the motivations, preferences, and satisfactions of individuals working on jigsaw puzzles, and she explores how these elements of play relate to the procedures and strategies puzzlers use to…

Flip-J: Development of the System for Flipped Jigsaw Supported Language Learning

ERIC Educational Resources Information Center

Yamada, Masanori; Goda, Yoshiko; Hata, Kojiro; Matsukawa, Hideya; Yasunami, Seisuke

2016-01-01

This study aims to develop and evaluate a language learning system supported by the "flipped jigsaw" technique, called "Flip-J". This system mainly consists of three functions: (1) the creation of a learning material database, (2) allocation of learning materials, and (3) formation of an expert and jigsaw group. Flip-J was…

Experience of cooperative learning in engineering

NASA Astrophysics Data System (ADS)

Maceiras, Rocio; Cancela, Angeles; Urréjola, Santiago; Sánchez, Angel

2011-03-01

The objective of this work is to share the authors' experience towards a different mode of teaching/learning method. Cooperative learning (Jigsaw) was employed on the University of Vigo's fourth-year engineering students. The results of the experience show that cooperative learning is quite a viable alternative to the classical way of lecturing at the university when the number of students is not too high. The authors' observation indicates that students did not show a lot of interest towards the new learning style but their resistance changed once they began the activity. The Jigsaw method has proved to be a useful tool for improving the learning process so that students have the opportunity to participate actively in the learning activities.

Effects of Jigsaw Cooperative Learning and Animation Techniques on Students' Understanding of Chemical Bonding and Their Conceptions of the Particulate Nature of Matter

NASA Astrophysics Data System (ADS)

Karacop, Ataman; Doymus, Kemal

2013-04-01

The aim of this study was to determine the effect of jigsaw cooperative learning and computer animation techniques on academic achievements of first year university students attending classes in which the unit of chemical bonding is taught within the general chemistry course and these students' learning of the particulate nature of matter of this unit. The sample of this study consisted of 115 first-year science education students who attended the classes in which the unit of chemical bonding was taught in a university faculty of education during the 2009-2010 academic year. The data collection instruments used were the Test of Scientific Reasoning, the Purdue Spatial Visualization Test: Rotations, the Chemical Bonding Academic Achievement Test, and the Particulate Nature of Matter Test in Chemical Bonding (CbPNMT). The study was carried out in three different groups. One of the groups was randomly assigned to the jigsaw group, the second was assigned to the animation group (AG), and the third was assigned to the control group, in which the traditional teaching method was applied. The data obtained with the instruments were evaluated using descriptive statistics, one-way ANOVA, and MANCOVA. The results indicate that the teaching of chemical bonding via the animation and jigsaw techniques was more effective than the traditional teaching method in increasing academic achievement. In addition, according to findings from the CbPNMT, the students from the AG were more successful in terms of correct understanding of the particulate nature of matter.

Revealing the Relationship between Reading Interest and Critical Thinking Skills through Remap GI and Remap Jigsaw

ERIC Educational Resources Information Center

Zubaidah, Siti; Corebima, Aloysius Duran; Mahanal, Susriyati; Mistianah

2018-01-01

The aim of this research was to reveal the relationship between student's reading interest and critical thinking skills through Reading Concept Map Group Investigation (Remap GI) and Reading Concept Map Jigsaw (Remap Jigsaw) learning models. To do so, two science classes from first grade of two Senior High Schools in Malang, Indonesia were…

A New Approach in Teaching the Features and Classifications of Invertebrate Animals in Biology Courses

ERIC Educational Resources Information Center

Sezek, Fatih

2013-01-01

This study examined the effectiveness of a new learning approach in teaching classification of invertebrate animals in biology courses. In this approach, we used an impersonal style: the subject jigsaw, which differs from the other jigsaws in that both course topics and student groups are divided. Students in Jigsaw group were divided into five…

Jigsaw Puzzles As Cognitive Enrichment (PACE) - the effect of solving jigsaw puzzles on global visuospatial cognition in adults 50 years of age and older: study protocol for a randomized controlled trial.

PubMed

Fissler, Patrick; Küster, Olivia C; Loy, Laura S; Laptinskaya, Daria; Rosenfelder, Martin J; von Arnim, Christine A F; Kolassa, Iris-Tatjana

2017-09-06

Neurocognitive disorders are an important societal challenge and the need for early prevention is increasingly recognized. Meta-analyses show beneficial effects of cognitive activities on cognition. However, high financial costs, low intrinsic motivation, logistic challenges of group-based activities, or the need to operate digital devices prevent their widespread application in clinical practice. Solving jigsaw puzzles is a cognitive activity without these hindering characteristics, but cognitive effects have not been investigated yet. With this study, we aim to evaluate the effect of solving jigsaw puzzles on visuospatial cognition, daily functioning, and psychological outcomes. The pre-posttest, assessor-blinded study will include 100 cognitively healthy adults 50 years of age or older, who will be randomly assigned to a jigsaw puzzle group or a cognitive health counseling group. Within the 5-week intervention period, participants in the jigsaw puzzle group will engage in 30 days of solving jigsaw puzzles for at least 1 h per day and additionally receive cognitive health counseling. The cognitive health counseling group will receive the same counseling intervention but no jigsaw puzzles. The primary outcome, global visuospatial cognition, will depict the average of the z-standardized performance scores in visuospatial tests of perception, constructional praxis, mental rotation, processing speed, flexibility, working memory, reasoning, and episodic memory. As secondary outcomes, we will assess the eight cognitive abilities, objective and subjective visuospatial daily functioning, psychological well-being, general self-efficacy, and perceived stress. The primary data analysis will be based on mixed-effects models in an intention-to-treat approach. Solving jigsaw puzzles is a low-cost, intrinsically motivating, cognitive leisure activity, which can be executed alone or with others and without the need to operate a digital device. In the case of positive results, these characteristics allow an easy implementation of solving jigsaw puzzles in clinical practice as a way to improve visuospatial functioning. Whether cognitive impairment and loss of independence in everyday functioning might be prevented or delayed in the long run has to be examined in future studies. ClinicalTrials.gov, NCT02667314 . Registered on 27 January 2016.

JIGSAW: Preference-directed, co-operative scheduling

NASA Technical Reports Server (NTRS)

Linden, Theodore A.; Gaw, David

1992-01-01

Techniques that enable humans and machines to cooperate in the solution of complex scheduling problems have evolved out of work on the daily allocation and scheduling of Tactical Air Force resources. A generalized, formal model of these applied techniques is being developed. It is called JIGSAW by analogy with the multi-agent, constructive process used when solving jigsaw puzzles. JIGSAW begins from this analogy and extends it by propagating local preferences into global statistics that dynamically influence the value and variable ordering decisions. The statistical projections also apply to abstract resources and time periods--allowing more opportunities to find a successful variable ordering by reserving abstract resources and deferring the choice of a specific resource or time period.

Influence on Learning of a Collaborative Learning Method Comprising the Jigsaw Method and Problem-based Learning (PBL).

PubMed

Takeda, Kayoko; Takahashi, Kiyoshi; Masukawa, Hiroyuki; Shimamori, Yoshimitsu

2017-01-01

Recently, the practice of active learning has spread, increasingly recognized as an essential component of academic studies. Classes incorporating small group discussion (SGD) are conducted at many universities. At present, assessments of the effectiveness of SGD have mostly involved evaluation by questionnaires conducted by teachers, by peer assessment, and by self-evaluation of students. However, qualitative data, such as open-ended descriptions by students, have not been widely evaluated. As a result, we have been unable to analyze the processes and methods involved in how students acquire knowledge in SGD. In recent years, due to advances in information and communication technology (ICT), text mining has enabled the analysis of qualitative data. We therefore investigated whether the introduction of a learning system comprising the jigsaw method and problem-based learning (PBL) would improve student attitudes toward learning; we did this by text mining analysis of the content of student reports. We found that by applying the jigsaw method before PBL, we were able to improve student attitudes toward learning and increase the depth of their understanding of the area of study as a result of working with others. The use of text mining to analyze qualitative data also allowed us to understand the processes and methods by which students acquired knowledge in SGD and also changes in students' understanding and performance based on improvements to the class. This finding suggests that the use of text mining to analyze qualitative data could enable teachers to evaluate the effectiveness of various methods employed to improve learning.

Teaching research methods in nursing using Aronson's Jigsaw Technique. A cross-sectional survey of student satisfaction.

PubMed

Leyva-Moral, Juan M; Riu Camps, Marta

2016-05-01

To adapt nursing studies to the European Higher Education Area, new teaching methods have been included that assign maximum importance to student-centered learning and collaborative work. The Jigsaw Technique is based on collaborative learning and everyone in the group must play their part because each student's mark depends on the other students. Home group members are given the responsibility to become experts in a specific area of knowledge. Experts meet together to reach an agreement and improve skills. Finally, experts return to their home groups to share all their findings. The aim of this study was to evaluate nursing student satisfaction with the Jigsaw Technique used in the context of a compulsory course in research methods for nursing. A cross-sectional study was conducted using a self-administered anonymous questionnaire administered to students who completed the Research Methods course during the 2012-13 and 2013-14 academic years. The questionnaire was developed taking into account the learning objectives, competencies and skills that should be acquired by students, as described in the course syllabus. The responses were compared by age group (younger or older than 22years). A total of 89.6% of nursing students under 22years believed that this methodology helped them to develop teamwork, while this figure was 79.6% in older students. Nursing students also believed it helped them to work independently, with differences according to age, 79.7% and 58% respectively (p=0.010). Students disagreed with the statement "The Jigsaw Technique involves little workload", with percentages of 88.5% in the group under 22years and 80% in older students. Most believed that this method should not be employed in upcoming courses, although there were differences by age, with 44.3% of the younger group being against and 62% of the older group (p=0.037). The method was not highly valued by students, mainly by those older than 22years, who concluded that they did not learn more with it than with other traditional techniques. The results of this study question whether this form of learning meets students' learning needs and its compatibility with individual and group realities. Copyright © 2016 Elsevier Ltd. All rights reserved.

Jigsaw: Because Reading Your Math Book Shouldn't Be a Puzzle.

ERIC Educational Resources Information Center

Draper, Roni Jo

1997-01-01

Describes a jigsaw puzzle activity, a two-part cooperative learning activity useful at any level of mathematics instruction, intended to teach students to become "strategic readers" of their mathematics textbooks. (SR)

Novel TPLO Alignment Jig/Saw Guide Reproduces Freehand and Ideal Osteotomy Positions

PubMed Central

2016-01-01

Objectives To evaluate the ability of an alignment jig/saw guide to reproduce appropriate osteotomy positions in the tibial plateau leveling osteotomy (TPLO) in the dog. Methods Lateral radiographs of 65 clinical TPLO procedures using an alignment jig and freehand osteotomy performed by experienced TPLO surgeons using a 24 mm radial saw blade between Dec 2005–Dec 2007 and Nov 2013–Nov 2015 were reviewed. The freehand osteotomy position was compared to potential osteotomy positions using the alignment jig/saw guide. The proximal and distal jig pin holes on postoperative radiographs were used to align the jig to the bone; saw guide position was selected to most closely match the osteotomy performed. The guide-to-osteotomy fit was categorized by the distance between the actual osteotomy and proposed saw guide osteotomy at its greatest offset (≤1 mm = excellent; ≤2 mm = good; ≤3 mm = satisfactory; >3 mm = poor). Results Sixty-four of 65 TPLO osteotomies could be matched satisfactorily by the saw guide. Proximal jig pin placement 3–4 mm from the joint surface and pin location in a craniocaudal plane on the proximal tibia were significantly associated with the guide-to-osteotomy fit (P = 0.021 and P = 0.047, respectively). Clinical Significance The alignment jig/saw guide can be used to reproduce appropriate freehand osteotomy position for TPLO. Furthermore, an ideal osteotomy position centered on the tibial intercondylar tubercles also is possible. Accurate placement of the proximal jig pin is a crucial step for correct positioning of the saw guide in either instance. PMID:27556230

Using the jigsaw cooperative learning method to teach medical students about long-term and postacute care.

PubMed

Buhr, Gwendolen T; Heflin, Mitchell T; White, Heidi K; Pinheiro, Sandro O

2014-06-01

Since many of the frailest and most vulnerable Americans reside in nursing homes, medical students need focused education and training pertaining to this setting. A unique cooperative learning experience utilizing the jigsaw method was developed to engage and expose students to the institutional long-term and postacute care (LTPAC) setting and the roles of personnel there. To accomplish these goals, small groups of medical students interviewed LTPAC personnel about their role, generally, and in relation to a specific patient case. These groups were then rearranged into new groups containing 1 student from each of the original groups plus a faculty facilitator. Each student in the new groups taught about the role of the LTPAC professional they interviewed. To assess the effectiveness of this learning experience, students and LTPAC personnel provided written feedback and rated the activity using a 5-point Likert scale (1 = worst; 5 = best). Students also took a knowledge test. The activity received ratings from students of 3.65 to 4.12 (mean = 3.91). The knowledge test results indicated that students understood the roles of the LTPAC personnel. In general, the jigsaw exercise was well-received by participants and provided an effective means of introducing medical students to the nursing home environment. Copyright © 2014 American Medical Directors Association, Inc. Published by Elsevier Inc. All rights reserved.

Foundations of Cooperative Learning.

ERIC Educational Resources Information Center

Jacobs, George M.

Five cooperative learning methods are described with the theories that support them. The five methods are: (1) Group Investigation (GI), developed by S. Sharan and others; (2) Jigsaw, developed by E. Aronson and others; (3) Student Teams Achievement Divisions (STAD), developed by R. E. Slavin and others; (4) Learning Together, developed by D. W.…

Using Jigsaw-Style Spectroscopy Problem-Solving to Elucidate Molecular Structure through Online Cooperative Learning

ERIC Educational Resources Information Center

Winschel, Grace A.; Everett, Renata K.; Coppola, Brian P.; Shultz, Ginger V.

2015-01-01

Cooperative learning was employed as an instructional approach to facilitate student development of spectroscopy problem solving skills. An interactive online environment was used as a framework to structure weekly discussions around spectroscopy problems outside of class. Weekly discussions consisted of modified jigsaw-style problem solving…

Impact of Expert Teaching Quality on Novice Academic Performance in the Jigsaw Cooperative Learning Method

NASA Astrophysics Data System (ADS)

Berger, Roland; Hänze, Martin

2015-01-01

We assessed the impact of expert students' instructional quality on the academic performance of novice students in 12th-grade physics classes organized in an expert model of cooperative learning ('jigsaw classroom'). The instructional quality of 129 expert students was measured by a newly developed rating system. As expected, when aggregating across all four subtopics taught, regression analysis revealed that academic performance of novice students increases with the quality of expert students' instruction. The difficulty of subtopics, however, moderates this effect: higher instructional quality of more difficult subtopics did not lead to better academic performance of novice students. We interpret this finding in the light of Cognitive Load Theory. Demanding tasks cause high intrinsic cognitive load and hindered the novice students' learning.

Effect of Jigsaw I Technique on Teaching Turkish Grammar

ERIC Educational Resources Information Center

Arslan, Akif

2016-01-01

The purpose of this study is to find out the effect of Jigsaw I technique on students' academic success and attitude towards the course in teaching Turkish grammar. For that purpose, three grammar topics (spelling and punctuation marks rules) were determined and an experimental study conforming to "control group preliminary-testing final…

Constructing Knowledge with an Agent-Based Instructional Program: A Comparison of Cooperative and Individual Meaning Making

ERIC Educational Resources Information Center

Moreno, Roxana

2009-01-01

Participants in the present study were 87 college students who learned about botany using an agent-based instructional program with three different learning approaches: individual, jigsaw, or cooperative learning. Results showed no differences among learning approaches on retention. Students in jigsaw groups reported higher cognitive load during…

Cooperative Learning: A Practical Application Strategy.

ERIC Educational Resources Information Center

Platte, Stephen A.

1991-01-01

Discusses a method of finding and implementing articles from among the sizeable amount of professional literature regarding cooperative learning. Describes the application of three teaching models (1) jigsaw, (2) group investigation, and (3) cybernetics that apply cooperative learning to elementary and secondary social studies instruction. (SG)

The Effects of Jigsaw Learning on Students' Attitudes in a Vietnamese Higher Education Classroom

ERIC Educational Resources Information Center

Tran, Van Dat; Lewis, Ramon

2012-01-01

As a part of an experimental study on the effects of jigsaw learning on Vietnamese tertiary students' achievement and knowledge retention, students' attitudes towards six weeks of this kind of instruction were assessed. As noted in our previous report, students in the experimental group (N = 40), who perceived their instruction as more cooperative…

Closing the Theory-Practice Gap: Physical Education Students' Use of Jigsaw Learning in a Secondary School

ERIC Educational Resources Information Center

O'Leary, Nick; Wattison, Nicole; Edwards, Toni; Bryan, Kate

2015-01-01

Recognising that the theory-practice gap remains problematic in the preparation of physical education (PE) teachers, this study sought to explore three undergraduate students use of jigsaw learning teaching gymnastics during a secondary school placement. Specifically, the research attempted to identify those issues that arose using this learning…

Children with Praderwilli Syndrome Vs. Williams Syndrome: Indirect Effects on Parents during a Jigsaw Puzzle Task

ERIC Educational Resources Information Center

Ly, T. M.; Hodapp, R. M.

2005-01-01

Background: Genetic disorders predispose individuals to exhibit characteristic behaviours, which in turn elicit particular behaviours from others. In response to the strength of Prader?Willi syndrome (PWS) and weakness of Williams syndrome (WS) in visual-spatial tasks such as jigsaw puzzles, parents' behaviours can be affected by their child's…

Gold-nanoparticle-mediated jigsaw-puzzle-like assembly of supersized plasmonic DNA origami.

PubMed

Yao, Guangbao; Li, Jiang; Chao, Jie; Pei, Hao; Liu, Huajie; Zhao, Yun; Shi, Jiye; Huang, Qing; Wang, Lianhui; Huang, Wei; Fan, Chunhai

2015-03-02

DNA origami has rapidly emerged as a powerful and programmable method to construct functional nanostructures. However, the size limitation of approximately 100 nm in classic DNA origami hampers its plasmonic applications. Herein, we report a jigsaw-puzzle-like assembly strategy mediated by gold nanoparticles (AuNPs) to break the size limitation of DNA origami. We demonstrated that oligonucleotide-functionalized AuNPs function as universal joint units for the one-pot assembly of parent DNA origami of triangular shape to form sub-microscale super-origami nanostructures. AuNPs anchored at predefined positions of the super-origami exhibited strong interparticle plasmonic coupling. This AuNP-mediated strategy offers new opportunities to drive macroscopic self-assembly and to fabricate well-defined nanophotonic materials and devices. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

The visual development of hand-centered receptive fields in a neural network model of the primate visual system trained with experimentally recorded human gaze changes

PubMed Central

Galeazzi, Juan M.; Navajas, Joaquín; Mender, Bedeho M. W.; Quian Quiroga, Rodrigo; Minini, Loredana; Stringer, Simon M.

2016-01-01

ABSTRACT Neurons have been found in the primate brain that respond to objects in specific locations in hand-centered coordinates. A key theoretical challenge is to explain how such hand-centered neuronal responses may develop through visual experience. In this paper we show how hand-centered visual receptive fields can develop using an artificial neural network model, VisNet, of the primate visual system when driven by gaze changes recorded from human test subjects as they completed a jigsaw. A camera mounted on the head captured images of the hand and jigsaw, while eye movements were recorded using an eye-tracking device. This combination of data allowed us to reconstruct the retinal images seen as humans undertook the jigsaw task. These retinal images were then fed into the neural network model during self-organization of its synaptic connectivity using a biologically plausible trace learning rule. A trace learning mechanism encourages neurons in the model to learn to respond to input images that tend to occur in close temporal proximity. In the data recorded from human subjects, we found that the participant’s gaze often shifted through a sequence of locations around a fixed spatial configuration of the hand and one of the jigsaw pieces. In this case, trace learning should bind these retinal images together onto the same subset of output neurons. The simulation results consequently confirmed that some cells learned to respond selectively to the hand and a jigsaw piece in a fixed spatial configuration across different retinal views. PMID:27253452

The visual development of hand-centered receptive fields in a neural network model of the primate visual system trained with experimentally recorded human gaze changes.

PubMed

Galeazzi, Juan M; Navajas, Joaquín; Mender, Bedeho M W; Quian Quiroga, Rodrigo; Minini, Loredana; Stringer, Simon M

2016-01-01

Neurons have been found in the primate brain that respond to objects in specific locations in hand-centered coordinates. A key theoretical challenge is to explain how such hand-centered neuronal responses may develop through visual experience. In this paper we show how hand-centered visual receptive fields can develop using an artificial neural network model, VisNet, of the primate visual system when driven by gaze changes recorded from human test subjects as they completed a jigsaw. A camera mounted on the head captured images of the hand and jigsaw, while eye movements were recorded using an eye-tracking device. This combination of data allowed us to reconstruct the retinal images seen as humans undertook the jigsaw task. These retinal images were then fed into the neural network model during self-organization of its synaptic connectivity using a biologically plausible trace learning rule. A trace learning mechanism encourages neurons in the model to learn to respond to input images that tend to occur in close temporal proximity. In the data recorded from human subjects, we found that the participant's gaze often shifted through a sequence of locations around a fixed spatial configuration of the hand and one of the jigsaw pieces. In this case, trace learning should bind these retinal images together onto the same subset of output neurons. The simulation results consequently confirmed that some cells learned to respond selectively to the hand and a jigsaw piece in a fixed spatial configuration across different retinal views.

Comparison of Two Small-Group Learning Methods in 12th-Grade Physics Classes Focusing on Intrinsic Motivation and Academic Performance

ERIC Educational Resources Information Center

Berger, Roland; Hanze, Martin

2009-01-01

Twelfth-grade physics classes with 344 students participated in a quasi-experimental study comparing two small-group learning settings. In the jigsaw classroom, in contrast to the cyclical rotation method, teaching expectancy as well as resource interdependence is established. The study is based on the self-determination theory of motivation,…

JIGSAW: Joint Inhomogeneity estimation via Global Segment Assembly for Water-fat separation.

PubMed

Lu, Wenmiao; Lu, Yi

2011-07-01

Water-fat separation in magnetic resonance imaging (MRI) is of great clinical importance, and the key to uniform water-fat separation lies in field map estimation. This work deals with three-point field map estimation, in which water and fat are modelled as two single-peak spectral lines, and field inhomogeneities shift the spectrum by an unknown amount. Due to the simplified spectrum modelling, there exists inherent ambiguity in forming field maps from multiple locally feasible field map values at each pixel. To resolve such ambiguity, spatial smoothness of field maps has been incorporated as a constraint of an optimization problem. However, there are two issues: the optimization problem is computationally intractable and even when it is solved exactly, it does not always separate water and fat images. Hence, robust field map estimation remains challenging in many clinically important imaging scenarios. This paper proposes a novel field map estimation technique called JIGSAW. It extends a loopy belief propagation (BP) algorithm to obtain an approximate solution to the optimization problem. The solution produces locally smooth segments and avoids error propagation associated with greedy methods. The locally smooth segments are then assembled into a globally consistent field map by exploiting the periodicity of the feasible field map values. In vivo results demonstrate that JIGSAW outperforms existing techniques and produces correct water-fat separation in challenging imaging scenarios.

Adding a Piece to the Leaf Epidermal Cell Shape Puzzle.

PubMed

von Wangenheim, Daniel; Wells, Darren M; Bennett, Malcolm J

2017-11-06

The jigsaw puzzle-shaped pavement cells in the leaf epidermis collectively function as a load-bearing tissue that controls organ growth. In this issue of Developmental Cell, Majda et al. (2017) shed light on how the jigsaw shape can arise from localized variations in wall stiffness between adjacent epidermal cells. Copyright © 2017 Elsevier Inc. All rights reserved.

Instructional Media Production for Early Childhood Education: A. B. C. Jig-Saw Puzzle, a Model

ERIC Educational Resources Information Center

Yusuf, Mudashiru Olalere; Olanrewaju, Olatayo Solomon; Soetan, Aderonke K.

2015-01-01

In this paper, a. b. c. jig-saw puzzle was produced for early childhood education using local materials. This study was a production based type of research, to serve as a supplemental or total learning resource. Its production followed four phases of development referred to as information, design, production and evaluation. The storyboard cards,…

Dramatherapy and Family Therapy in Education: Essential Pieces of the Multi-Agency Jigsaw

ERIC Educational Resources Information Center

McFarlane, Penny; Harvey, Jenny

2012-01-01

A collaborative therapeutic approach often proves the best way to assess and meet the needs of children experiencing barriers to learning. This book gives a concise overview of drama and family therapy and describes how both therapies can work together to provide essential pieces of the jigsaw of emotional support for troubled children within an…

Blending the CoI Model with Jigsaw Technique for Pre-Service Foreign Language Teachers' Continuing Professional Development Using Open Sim and Sloodle

ERIC Educational Resources Information Center

Pellas, Nikolaos; Boumpa, Anna

2017-01-01

This study seeks to investigate the effect of pre-service foreign language teachers' interactions on their continuing professional development (CPD), using a theoretical instructional design framework consisted of the three presence indicators of a Community of Inquiry (CoI) model and the Jigsaw teaching technique. The investigation was performed…

Using Captioned Tactile Jigsaw Flashcards in Teaching Vocabulary to Children with Special Educational Needs

ERIC Educational Resources Information Center

Król-Gierat, Werona

2014-01-01

The aim of the present paper is to show how captioned tactile jigsaw flashcards (CTJF) can be used in teaching English vocabulary to children with special educational needs. The idea of the following technique, inspired by Montessori's Three Period Lesson (1964, 1967a, 1967b), was presented by this author and colleague Dorota Beltkiewicz in March…

Having Fun and Accepting Challenges Are Natural Instincts: Jigsaw Puzzles to Challenge Students and Test Their Abilities While Having Fun!

ERIC Educational Resources Information Center

Rodenbaugh, Hanna R.; Lujan, Heidi L.; Rodenbaugh, David W.; DiCarlo, Stephen E.

2014-01-01

Because jigsaw puzzles are fun, and challenging, students will endure and discover that persistence and grit are rewarded. Importantly, play and fun have a biological place just like sleep and dreams. Students also feel a sense of accomplishment when they have completed a puzzle. Importantly, the reward of mastering a challenge builds confidence…

Jigsaw Puzzles and River Banks: Two Ways of Picturing Our Future

ERIC Educational Resources Information Center

Kretchmar, R. Scott

2005-01-01

The papers presented at the 2004 Academy meetings can be thought of as pieces from jigsaw puzzles. While the employment of this metaphor over the years has been useful, we may be ready for a new image, one that is both more accurate and inspiring. We can picture ourselves working at different locations along a river bank. Some of us work upstream,…

Tips for Teachers: Lesson Plans and Ideas from around the World.

ERIC Educational Resources Information Center

Mathieson, Murray; And Others

1990-01-01

The following ideas are presented: (1) working together in calculus, including a handout for a jigsaw lesson; (2) a lesson on water and ecology from the USSR using the collective teaching technique; (3) the Israeli Havruta "Companionship" method for peer teaching; and (4) an origami lesson outlined and illustrated. (JD)

Implementation of Cooperative Learning Model in Preschool

ERIC Educational Resources Information Center

Akçay, Nilüfer Okur

2016-01-01

In this study, the effectivity of jigsaw method, one of the cooperative learning models, on teaching the concepts related to sense organs and their functions to four-five year-old children in nursery class was analyzed. The study is in the semi-experimental design consisting of experimental and control groups and pretest and posttest. The sample…

The Effect of Jigsaw Technique on 6th Graders' Learning of Force and Motion Unit and Their Science Attitudes and Motivation

ERIC Educational Resources Information Center

Ural, Evrim; Ercan, Orhan; Gençoglan, Durdu Mehmet

2017-01-01

The study aims to investigate the effects of jigsaw technique on 6th graders' learning of "Force and Motion" unit, their science learning motivation and their attitudes towards science classes. The sample of the study consisted of 49 6th grade students from two different classes taking the Science and Technology course at a government…

Effects of Jigsaw Cooperative Learning and Animation Techniques on Students' Understanding of Chemical Bonding and Their Conceptions of the Particulate Nature of Matter

ERIC Educational Resources Information Center

Karacop, Ataman; Doymus, Kemal

2013-01-01

The aim of this study was to determine the effect of jigsaw cooperative learning and computer animation techniques on academic achievements of first year university students attending classes in which the unit of chemical bonding is taught within the general chemistry course and these students' learning of the particulate nature of matter of this…

The Effect of Using Jigsaw Strategy in Teaching Science on the Acquisition of Scientific Concepts among the Fourth Graders of Bani Kinana Directorate of Education

ERIC Educational Resources Information Center

Hamadneh, Qaseem Mohammad Salim

2017-01-01

The study aimed to identify the effect of using Jigsaw strategy in teaching science on the acquisition of scientific concepts among the fourth graders of Bani Kinana Directorate of Education compared to the traditional way. The study sample consisted of 70 male and female students, divided into two groups: experimental and control where the…

Using Moos To Help Learn English; Video Jigsaw; Practicing Speaking with Follow-Up Interviews and Student-Read Dictations; "Ask the Expert": Oral Presentations that Work; The Medium Is the Message.

ERIC Educational Resources Information Center

Miller, James; Reynolds, Judith; Noble, P. C.; Altschuler, Lee; Schauber, Holli

2001-01-01

Four short articles provide teaching tips for the English-as-a-Second/Foreign-Language classroom, including the use of Moos, a video jigsaw, practicing oral language skills with interviews and student-read dictations, an ask the expert activity which builds learner confidence in speaking in front of groups of people. (Author/VWL)

Evolution of Humans: Understanding the Nature and Methods of Science through Cooperative Learning

ERIC Educational Resources Information Center

Lee, Yeung Chung

2011-01-01

This article describes the use of an enquiry-based approach to the study of human evolution in a practical context, integrating role-playing, jigsaw cooperative learning and scientific argumentation. The activity seeks to unravel the evolutionary relationships of five hominids and one ape from rather "messy" evidence. This approach enhanced the…

An Alternative View of Forest Sampling

Treesearch

Francis A. Roesch; Edwin J. Green; Charles T. Scott

1993-01-01

A generalized concept is presented for all of the commonly used methods of forest sampling. The concept views the forest as a two-dimensional picture which is cut up into pieces like a jigsaw puzzle, with the pieces defined by the individual selection probabilities of the trees in the forest. This concept results in a finite number of independently selected sample...

The Impact of Teaching the Subjects under "Science in Time" Unit in the Social Studies Class in the 7th Grade Using Jigsaw Technique on the Academic Success of the Students

ERIC Educational Resources Information Center

Er, Harun

2017-01-01

The main point in today's educational approach is that it is based on a student-centered approach. One of the alternative instruction techniques having a convenient content for this system is the jigsaw technique. Since the introduction of this technique, it has been applied into many different fields of education, and determined that it…

Creation and implementation of a flipped jigsaw activity to stimulate interest in biochemistry among medical students.

PubMed

Williams, Charlene; Perlis, Susan; Gaughan, John; Phadtare, Sangita

2018-05-06

Learner-centered pedagogical methods that are based on clinical application of basic science concepts through active learning and problem solving are shown to be effective for improving knowledge retention. As the clinical relevance of biochemistry is not always apparent to health-profession students, effective teaching of medical biochemistry should highlight the implications of biochemical concepts in pathology, minimize memorization, and make the concepts memorable for long-term retention. Here, we report the creation and successful implementation of a flipped jigsaw activity that was developed to stimulate interest in learning biochemistry among medical students. The activity combined the elements of a flipped classroom for learning concepts followed by a jigsaw activity to retrieve these concepts by solving clinical cases, answering case-based questions, and creating concept maps. The students' reception of the activity was very positive. They commented that the activity provided them an opportunity to review and synthesize information, helped to gage their learning by applying this information and work with peers. Students' improved performance especially for answering the comprehension-based questions correctly in the postquiz as well as the depth of information included in the postquiz concept maps suggested that the activity helped them to understand how different clinical scenarios develop owing to deviations in basic biochemical pathways. Although this activity was created for medical students, the format of this activity can also be useful for other health-professional students as well as undergraduate and graduate students. © 2018 by The International Union of Biochemistry and Molecular Biology, 2018. © 2018 The International Union of Biochemistry and Molecular Biology.

Designing Student Groupwork in Management Education: Widening the Palette of Options

ERIC Educational Resources Information Center

Holtham, Clive W.; Melville, Robert R.; Sodhi, ManMohan S.

2006-01-01

The authors describe innovation in practice through the unusual deployment of teams in a master's in management core course. Two parallel uses of teams were made, both drawing on the jigsaw team method, in one case with the team supporting individual work. The experiences support the idea of widening the palette of types of groupwork used in…

A new technique for solving puzzles.

PubMed

Makridis, Michael; Papamarkos, Nikos

2010-06-01

This paper proposes a new technique for solving jigsaw puzzles. The novelty of the proposed technique is that it provides an automatic jigsaw puzzle solution without any initial restriction about the shape of pieces, the number of neighbor pieces, etc. The proposed technique uses both curve- and color-matching similarity features. A recurrent procedure is applied, which compares and merges puzzle pieces in pairs, until the original puzzle image is reformed. Geometrical and color features are extracted on the characteristic points (CPs) of the puzzle pieces. CPs, which can be considered as high curvature points, are detected by a rotationally invariant corner detection algorithm. The features which are associated with color are provided by applying a color reduction technique using the Kohonen self-organized feature map. Finally, a postprocessing stage checks and corrects the relative position between puzzle pieces to improve the quality of the resulting image. Experimental results prove the efficiency of the proposed technique, which can be further extended to deal with even more complex jigsaw puzzle problems.

Comparison of two different techniques of cooperative learning approach: Undergraduates' conceptual understanding in the context of hormone biochemistry.

PubMed

Mutlu, Ayfer

2018-03-01

The purpose of the research was to compare the effects of two different techniques of the cooperative learning approach, namely Team-Game Tournament and Jigsaw, on undergraduates' conceptual understanding in a Hormone Biochemistry course. Undergraduates were randomly assigned to Group 1 (N = 23) and Group 2 (N = 29). Instructions were accomplished using Team-Game Tournament in Group 1 and Jigsaw in Group 2. Before the instructions, all groups were informed about cooperative learning and techniques, their responsibilities in the learning process and accessing of resources. Instructions were conducted under the guidance of the researcher for nine weeks and the Hormone Concept Test developed by the researcher was used before and after the instructions for data collection. According to the results, while both techniques improved students' understanding, Jigsaw was more effective than Team-Game Tournament. © 2017 by The International Union of Biochemistry and Molecular Biology, 46(2):114-120, 2018. © 2017 The International Union of Biochemistry and Molecular Biology.

Children with Prader-Willi syndrome vs. Williams syndrome: indirect effects on parents during a jigsaw puzzle task.

PubMed

Ly, T M; Hodapp, R M

2005-12-01

Genetic disorders predispose individuals to exhibit characteristic behaviours, which in turn elicit particular behaviours from others. In response to the strength of Prader-Willi syndrome (PWS) and weakness of Williams syndrome (WS) in visual-spatial tasks such as jigsaw puzzles, parents' behaviours can be affected by their child's level of puzzle ability or syndrome diagnosis. Children were asked to complete two jigsaw puzzles (one with the experimenter and the other with the parent) for 5 min each. Frequencies of parental helping and reinforcement behaviours, along with ratings of parental directiveness, were examined as parents interacted with their children on a jigsaw puzzle task. Within each aetiological group, correlates of parental behaviours with child characteristics were also examined. Compared to parents of children with PWS, parents of children with WS engaged in a more directive style of interaction, and provided more help and reinforcement. Relative to parents of children with higher puzzle abilities (from both aetiologies), parents of children with lower abilities also showed the same pattern. Both the child's aetiology and puzzle abilities were important in predicting parents' directiveness and helping and reinforcement behaviours. Within the PWS group, parents' behaviours correlated negatively with the child's puzzle abilities and general cognitive functioning; no such relations occurred in the WS group. Parents' behaviours were affected by both the child's diagnosis and actual puzzle abilities, suggesting important implications for understanding and intervening with parents and children with different genetic syndromes.

Effects of a Cooperative Learning Strategy on Teaching and Learning Phases of Matter and One-Component Phase Diagrams

ERIC Educational Resources Information Center

Doymus, Kemal

2007-01-01

This study aims to determine the effects of cooperative learning (using the jigsaw method) on students' achievement in a general chemistry course. The Chemistry Achievement Test (CAT) and Phase Achievement Test (PAT) were used. The questions on the CAT relate to solids, liquids, gases, bonding, matter, and matter states. This test was given to…

Novel TPLO Alignment Jig/Saw Guide Reproduces Freehand and Ideal Osteotomy Positions.

PubMed

Mariano, Abigail D; Kowaleski, Michael P; Boudrieau, Randy J

2016-01-01

To evaluate the ability of an alignment jig/saw guide to reproduce appropriate osteotomy positions in the tibial plateau leveling osteotomy (TPLO) in the dog. Lateral radiographs of 65 clinical TPLO procedures using an alignment jig and freehand osteotomy performed by experienced TPLO surgeons using a 24 mm radial saw blade between Dec 2005-Dec 2007 and Nov 2013-Nov 2015 were reviewed. The freehand osteotomy position was compared to potential osteotomy positions using the alignment jig/saw guide. The proximal and distal jig pin holes on postoperative radiographs were used to align the jig to the bone; saw guide position was selected to most closely match the osteotomy performed. The guide-to-osteotomy fit was categorized by the distance between the actual osteotomy and proposed saw guide osteotomy at its greatest offset (≤1 mm = excellent; ≤2 mm = good; ≤3 mm = satisfactory; >3 mm = poor). Sixty-four of 65 TPLO osteotomies could be matched satisfactorily by the saw guide. Proximal jig pin placement 3-4 mm from the joint surface and pin location in a craniocaudal plane on the proximal tibia were significantly associated with the guide-to-osteotomy fit (P = 0.021 and P = 0.047, respectively). The alignment jig/saw guide can be used to reproduce appropriate freehand osteotomy position for TPLO. Furthermore, an ideal osteotomy position centered on the tibial intercondylar tubercles also is possible. Accurate placement of the proximal jig pin is a crucial step for correct positioning of the saw guide in either instance.

Particle Filter with State Permutations for Solving Image Jigsaw Puzzles

PubMed Central

Yang, Xingwei; Adluru, Nagesh; Latecki, Longin Jan

2016-01-01

We deal with an image jigsaw puzzle problem, which is defined as reconstructing an image from a set of square and non-overlapping image patches. It is known that a general instance of this problem is NP-complete, and it is also challenging for humans, since in the considered setting the original image is not given. Recently a graphical model has been proposed to solve this and related problems. The target label probability function is then maximized using loopy belief propagation. We also formulate the problem as maximizing a label probability function and use exactly the same pairwise potentials. Our main contribution is a novel inference approach in the sampling framework of Particle Filter (PF). Usually in the PF framework it is assumed that the observations arrive sequentially, e.g., the observations are naturally ordered by their time stamps in the tracking scenario. Based on this assumption, the posterior density over the corresponding hidden states is estimated. In the jigsaw puzzle problem all observations (puzzle pieces) are given at once without any particular order. Therefore, we relax the assumption of having ordered observations and extend the PF framework to estimate the posterior density by exploring different orders of observations and selecting the most informative permutations of observations. This significantly broadens the scope of applications of the PF inference. Our experimental results demonstrate that the proposed inference framework significantly outperforms the loopy belief propagation in solving the image jigsaw puzzle problem. In particular, the extended PF inference triples the accuracy of the label assignment compared to that using loopy belief propagation. PMID:27795660

Cadastral Map Assembling Using Generalized Hough Transformation

NASA Astrophysics Data System (ADS)

Liu, Fei; Ohyama, Wataru; Wakabayashi, Tetsushi; Kimura, Fumitaka

There are numerous cadastral maps generated by the past land surveying. The raster digitization of these paper maps is in progress. For effective and efficient use of these maps, we have to assemble the set of maps to make them superimposable on other geographic information in a GIS. The problem can be seen as a complex jigsaw puzzle where the pieces are the cadastral sections extracted from the map. We present an automatic solution to this geographic jigsaw puzzle, based on the generalized Hough transformation that detects the longest common boundary between every piece and its neighbors. The experiments have been conducted using the map of Mie Prefecture, Japan and the French cadastral map. The results of the experiments with the French cadastral maps showed that the proposed method, which consists of a flood filling procedure of internal area and detection and normalization of the north arrow direction, is suitable for assembling the cadastral map. The final goal of the process is to integrate every piece of the puzzle into a national geographic reference frame and database.

Introduction of active learning method in learning physiology by MBBS students.

PubMed

Gilkar, Suhail Ahmad; Lone, Shabiruddin; Lone, Riyaz Ahmad

2016-01-01

Active learning has received considerable attention over the past several years, often presented or perceived as a radical change from traditional instruction methods. Current research on learning indicates that using a variety of teaching strategies in the classroom increases student participation and learning. To introduce active learning methodology, i.e., "jigsaw technique" in undergraduate medical education and assess the student and faculty response to it. This study was carried out in the Department of Physiology in a Medical College of North India. A topic was chosen and taught using one of the active learning methods (ALMs), i.e., jigsaw technique. An instrument (questionnaire) was developed in English through an extensive review of literature and was properly validated. The students were asked to give their response on a five-point Likert scale. The feedback was kept anonymous. Faculty also provided their feedback in a separately provided feedback proforma. The data were collected, compiled, and analyzed. Of 150 students of MBBS-first year batch 2014, 142 participated in this study along with 14 faculty members of the Physiology Department. The majority of the students (>90%) did welcome the introduction of ALM and strongly recommended the use of such methods in teaching many more topics in future. 100% faculty members were of the opinion that many more topics shall be taken up using ALMs. This study establishes the fact that both the medical students and faculty want a change from the traditional way of passive, teacher-centric learning, to the more active teaching-learning techniques.

Impact of Jigsaw on the Achievement and Attitudes of Saudi Arabian Male High School Science Students

NASA Astrophysics Data System (ADS)

Alghamdi, Abdulmonem

The aim of the study is to investigate the impact of cooperative learning instruction, specifically by using the Jigsaw instructional strategy on science achievement and attitudes towards science among 11th grade students. Based upon previous research literature, it was hypothesized that significant differences existed on gains between general science achievement of experimental group and control group. The quasi-experimental design was chosen for this study. The study sample consisted of 50 students of 11th grade class who were equally distributed among experimental group and control group, matched on the basic of their annual examination at general science scores. The students' achievement was measured through the implementation of 30-item achievement test used as a pretest, as well as a posttest and deferred (follow-up) test. The experiment group was taught through cooperative learning while control group was taught through the instructions of "traditional teaching". The material was used such as lesson plans, worksheets and quizzes, designed to implement Jigsaw as a cooperative learning methodology. For the attitude scale towards science, a published 30-item Likert scale called Test of Science Related Attitudes (TOSRA) has been translated to Arabic in order to determine the students' attitudes ranging between strongly agree to strongly disagree. The data were analyzed through repeated measure analysis and multivariate analysis of variance with a .05 selected level of significance. The results of this study showed that using Jigsaw as a cooperative learning strategy has improved the students' achievement for the benefit of the experimental group. However, there was no significant change on the students' attitudes towards science for both groups, where the scores of all the attitude subscales were at or near the neutral level.

Designing Cooperative Learning in the Science Classroom: Integrating the Peer Tutoring Small Investigation Group (PTSIG) within the Model of the Six Mirrors of the Classroom Model

ERIC Educational Resources Information Center

Lazarowitz, Reuven; Hertz-Lazarowitz, Rachel; Khalil, Mahmood; Ron, Salit

2013-01-01

The model of the six mirrors of the classroom and its use in teaching biology in a cooperative learning mode were implemented in high school classrooms. In this study we present: a) The model of the six mirrors of the classroom (MSMC). b) Cooperative learning settings: 1. The Group Investigation; 2. The Jigsaw Method; and 3. Peer Tutoring in Small…

How Can Visual Analytics Assist Investigative Analysis? Design Implications from an Evaluation.

PubMed

Youn-Ah Kang; Görg, Carsten; Stasko, John

2011-05-01

Despite the growing number of systems providing visual analytic support for investigative analysis, few empirical studies of the potential benefits of such systems have been conducted, particularly controlled, comparative evaluations. Determining how such systems foster insight and sensemaking is important for their continued growth and study, however. Furthermore, studies that identify how people use such systems and why they benefit (or not) can help inform the design of new systems in this area. We conducted an evaluation of the visual analytics system Jigsaw employed in a small investigative sensemaking exercise, and compared its use to three other more traditional methods of analysis. Sixteen participants performed a simulated intelligence analysis task under one of the four conditions. Experimental results suggest that Jigsaw assisted participants to analyze the data and identify an embedded threat. We describe different analysis strategies used by study participants and how computational support (or the lack thereof) influenced the strategies. We then illustrate several characteristics of the sensemaking process identified in the study and provide design implications for investigative analysis tools based thereon. We conclude with recommendations on metrics and techniques for evaluating visual analytics systems for investigative analysis.

DNA is structured as a linear "jigsaw puzzle" in the genomes of Arabidopsis, rice, and budding yeast.

PubMed

Liu, Yun-Hua; Zhang, Meiping; Wu, Chengcang; Huang, James J; Zhang, Hong-Bin

2014-01-01

Knowledge of how a genome is structured and organized from its constituent elements is crucial to understanding its biology and evolution. Here, we report the genome structuring and organization pattern as revealed by systems analysis of the sequences of three model species, Arabidopsis, rice and yeast, at the whole-genome and chromosome levels. We found that all fundamental function elements (FFE) constituting the genomes, including genes (GEN), DNA transposable elements (DTE), retrotransposable elements (RTE), simple sequence repeats (SSR), and (or) low complexity repeats (LCR), are structured in a nonrandom and correlative manner, thus leading to a hypothesis that the DNA of the species is structured as a linear "jigsaw puzzle". Furthermore, we showed that different FFE differ in their importance in the formation and evolution of the DNA jigsaw puzzle structure between species. DTE and RTE play more important roles than GEN, LCR, and SSR in Arabidopsis, whereas GEN and RTE play more important roles than LCR, SSR, and DTE in rice. The genes having multiple recognized functions play more important roles than those having single functions. These results provide useful knowledge necessary for better understanding genome biology and evolution of the species and for effective molecular breeding of rice.

Puzzles, Pastimes, Problems.

ERIC Educational Resources Information Center

Eperson, D. B.

1987-01-01

Presents five puzzles or problems that may be used for mathematics enrichment. Ideas include magic squares, tests for divisibility, geometry, palindromic numbers, and a jigsaw puzzle. Solutions are included. (PK)

Sequential Monte Carlo for Maximum Weight Subgraphs with Application to Solving Image Jigsaw Puzzles.

PubMed

Adluru, Nagesh; Yang, Xingwei; Latecki, Longin Jan

2015-05-01

We consider a problem of finding maximum weight subgraphs (MWS) that satisfy hard constraints in a weighted graph. The constraints specify the graph nodes that must belong to the solution as well as mutual exclusions of graph nodes, i.e., pairs of nodes that cannot belong to the same solution. Our main contribution is a novel inference approach for solving this problem in a sequential monte carlo (SMC) sampling framework. Usually in an SMC framework there is a natural ordering of the states of the samples. The order typically depends on observations about the states or on the annealing setup used. In many applications (e.g., image jigsaw puzzle problems), all observations (e.g., puzzle pieces) are given at once and it is hard to define a natural ordering. Therefore, we relax the assumption of having ordered observations about states and propose a novel SMC algorithm for obtaining maximum a posteriori estimate of a high-dimensional posterior distribution. This is achieved by exploring different orders of states and selecting the most informative permutations in each step of the sampling. Our experimental results demonstrate that the proposed inference framework significantly outperforms loopy belief propagation in solving the image jigsaw puzzle problem. In particular, our inference quadruples the accuracy of the puzzle assembly compared to that of loopy belief propagation.

Sequential Monte Carlo for Maximum Weight Subgraphs with Application to Solving Image Jigsaw Puzzles

PubMed Central

Adluru, Nagesh; Yang, Xingwei; Latecki, Longin Jan

2015-01-01

We consider a problem of finding maximum weight subgraphs (MWS) that satisfy hard constraints in a weighted graph. The constraints specify the graph nodes that must belong to the solution as well as mutual exclusions of graph nodes, i.e., pairs of nodes that cannot belong to the same solution. Our main contribution is a novel inference approach for solving this problem in a sequential monte carlo (SMC) sampling framework. Usually in an SMC framework there is a natural ordering of the states of the samples. The order typically depends on observations about the states or on the annealing setup used. In many applications (e.g., image jigsaw puzzle problems), all observations (e.g., puzzle pieces) are given at once and it is hard to define a natural ordering. Therefore, we relax the assumption of having ordered observations about states and propose a novel SMC algorithm for obtaining maximum a posteriori estimate of a high-dimensional posterior distribution. This is achieved by exploring different orders of states and selecting the most informative permutations in each step of the sampling. Our experimental results demonstrate that the proposed inference framework significantly outperforms loopy belief propagation in solving the image jigsaw puzzle problem. In particular, our inference quadruples the accuracy of the puzzle assembly compared to that of loopy belief propagation. PMID:26052182

Laminated and infused Parafilm® - paper for paper-based analytical devices.

PubMed

Kim, Yong Shin; Yang, Yuanyuan; Henry, Charles S

2018-02-01

Numerous fabrication methods have been reported for microfluidic paper-based analytical devices (μPADs) using barrier materials ranging from photoresist to wax. While these methods have been used with wide success, consistently producing small, high-resolution features using materials and methods that are compatible with solvents and surfactants remains a challenge. Two new methods are presented here for generating μPADs with well-defined, high-resolution structures compatible with solvents and surfactant-containing solutions by partially or fully fusing paper with Parafilm® followed by cutting with a CO 2 laser cutter. Partial fusion leads to laminated paper ( l -paper) while the complete fusion results in infused paper ( i -paper). Patterned structures in l -paper were fabricated by selective removal of the paper but not the underlying Parafilm® using a benchtop CO 2 laser. Under optimized conditions, a gap as small as 137 ± 22 μm could be generated. Using this approach, a miniaturized paper 384-zone plate, consisting of circular detection elements with a diameter of 1.86 mm, was fabricated in 64 × 43 mm 2 area. Furthermore, these ablation-patterned substrates were confirmed to be compatible with surfactant solutions and common organic solvents (methanol, acetonitrile and dimethylformamide), which has been achieved by very few μPAD patterning techniques. Patterns in i -paper were created by completely cutting out zones of the i -paper and then fixing pre-cut paper into these openings similar to the strategy of fitting a jigsaw piece into a puzzle. Upon heating, unmodified paper was readily sealed into these openings due to partial reflow of the paraffin into the paper. This unique and simple bonding method was illustrated by two types of 3D μPADs, a push-on valve and a time-gated flow distributor, without adding adhesive layers. The free-standing jigsaw-patterned sheets showed good structural stability and solution compatibility, which provided a facile alternative method for fabricating complicated μPADs.

Optical image encryption by random shifting in fractional Fourier domains

NASA Astrophysics Data System (ADS)

Hennelly, B.; Sheridan, J. T.

2003-02-01

A number of methods have recently been proposed in the literature for the encryption of two-dimensional information by use of optical systems based on the fractional Fourier transform. Typically, these methods require random phase screen keys for decrypting the data, which must be stored at the receiver and must be carefully aligned with the received encrypted data. A new technique based on a random shifting, or jigsaw, algorithm is proposed. This method does not require the use of phase keys. The image is encrypted by juxtaposition of sections of the image in fractional Fourier domains. The new method has been compared with existing methods and shows comparable or superior robustness to blind decryption. Optical implementation is discussed, and the sensitivity of the various encryption keys to blind decryption is examined.

A Theoretical Model of Jigsaw-Puzzle Pattern Formation by Plant Leaf Epidermal Cells.

PubMed

Higaki, Takumi; Kutsuna, Natsumaro; Akita, Kae; Takigawa-Imamura, Hisako; Yoshimura, Kenji; Miura, Takashi

2016-04-01

Plant leaf epidermal cells exhibit a jigsaw puzzle-like pattern that is generated by interdigitation of the cell wall during leaf development. The contribution of two ROP GTPases, ROP2 and ROP6, to the cytoskeletal dynamics that regulate epidermal cell wall interdigitation has already been examined; however, how interactions between these molecules result in pattern formation remains to be elucidated. Here, we propose a simple interface equation model that incorporates both the cell wall remodeling activity of ROP GTPases and the diffusible signaling molecules by which they are regulated. This model successfully reproduces pattern formation observed in vivo, and explains the counterintuitive experimental results of decreased cellulose production and increased thickness. Our model also reproduces the dynamics of three-way cell wall junctions. Therefore, this model provides a possible mechanism for cell wall interdigitation formation in vivo.

Jigsaw model of the origin of life

NASA Astrophysics Data System (ADS)

McGowan, John F.

2002-02-01

It is suggested that life originated in a three-step process referred to as the jigsaw model. RNA, proteins, or similar organic molecules polymerized in a dehydrated carbon-rich environment, on surfaces in a carbon-rich environment, or in another environment where polymerization occurs. These polymers subsequently entered an aqueous environment where they folded into compact structures. It is argued that the folding of randomly generated polymers such as RNA or proteins in water tends to partition the folded polymer into domains with hydrophobic cores and matching shapes to minimize energy. In the aqueous environment hydrolysis or other reactions fragmented the compact structures into two or more matching molecules, occasionally producing simple living systems, also knows as autocatalytic sets of molecules. It is argued that the hydrolysis of folded polymers such as RNA or proteins is not random. The hydrophobic cores of the domains are rarely bisected due to the energy requirements in water. Hydrolysis preferentially fragments the folded polymers into pieces with complementary structures and chemical affinities. Thus the probability of producing a system of matched, interacting molecules in prebiotic chemistry is much higher than usually estimated. Environments where this process may occur are identified. For example, the jigsaw model suggests life may have originated at a seep or carbonaceous fluids beneath the ocean. The polymerization occurred beneath the sea floor. The folding and fragmentation occurred in the ocean. The implications of this hypothesis for seeking life or prebiotic chemistry in the Solar System are explored.

Bio-inspired ``jigsaw''-like interlocking sutures: Modeling, optimization, 3D printing and testing

NASA Astrophysics Data System (ADS)

Malik, I. A.; Mirkhalaf, M.; Barthelat, F.

2017-05-01

Structural biological materials such as bone, teeth or mollusk shells draw their remarkable performance from a sophisticated interplay of architectures and weak interfaces. Pushed to the extreme, this concept leads to sutured materials, which contain thin lines with complex geometries. Sutured materials are prominent in nature, and have recently served as bioinspiration for toughened ceramics and glasses. Sutures can generate large deformations, toughness and damping in otherwise all brittle systems and materials. In this study we examine the design and optimization of sutures with a jigsaw puzzle-like geometry, focusing on the non-linear traction behavior generated by the frictional pullout of the jigsaw tabs. We present analytical models which accurately predict the entire pullout response. Pullout strength and energy absorption increase with higher interlocking angles and for higher coefficients of friction, but the associated high stresses in the solid may fracture the tabs. Systematic optimization reveals a counter-intuitive result: the best pullout performance is achieved with interfaces with low coefficient of friction and high interlocking angle. We finally use 3D printing and mechanical testing to verify the accuracy of the models and of the optimization. The models and guidelines we present here can be extended to other types of geometries and sutured materials subjected to other loading/boundary conditions. The nonlinear responses of sutures are particularly attractive to augment the properties and functionalities of inherently brittle materials such as ceramics and glasses.

Query-by-example surgical activity detection.

PubMed

Gao, Yixin; Vedula, S Swaroop; Lee, Gyusung I; Lee, Mija R; Khudanpur, Sanjeev; Hager, Gregory D

2016-06-01

Easy acquisition of surgical data opens many opportunities to automate skill evaluation and teaching. Current technology to search tool motion data for surgical activity segments of interest is limited by the need for manual pre-processing, which can be prohibitive at scale. We developed a content-based information retrieval method, query-by-example (QBE), to automatically detect activity segments within surgical data recordings of long duration that match a query. The example segment of interest (query) and the surgical data recording (target trial) are time series of kinematics. Our approach includes an unsupervised feature learning module using a stacked denoising autoencoder (SDAE), two scoring modules based on asymmetric subsequence dynamic time warping (AS-DTW) and template matching, respectively, and a detection module. A distance matrix of the query against the trial is computed using the SDAE features, followed by AS-DTW combined with template scoring, to generate a ranked list of candidate subsequences (substrings). To evaluate the quality of the ranked list against the ground-truth, thresholding conventional DTW distances and bipartite matching are applied. We computed the recall, precision, F1-score, and a Jaccard index-based score on three experimental setups. We evaluated our QBE method using a suture throw maneuver as the query, on two tool motion datasets (JIGSAWS and MISTIC-SL) captured in a training laboratory. We observed a recall of 93, 90 and 87 % and a precision of 93, 91, and 88 % with same surgeon same trial (SSST), same surgeon different trial (SSDT) and different surgeon (DS) experiment setups on JIGSAWS, and a recall of 87, 81 and 75 % and a precision of 72, 61, and 53 % with SSST, SSDT and DS experiment setups on MISTIC-SL, respectively. We developed a novel, content-based information retrieval method to automatically detect multiple instances of an activity within long surgical recordings. Our method demonstrated adequate recall across different complexity datasets and experimental conditions.

A Theoretical Model of Jigsaw-Puzzle Pattern Formation by Plant Leaf Epidermal Cells

PubMed Central

Higaki, Takumi; Kutsuna, Natsumaro; Akita, Kae; Takigawa-Imamura, Hisako; Yoshimura, Kenji; Miura, Takashi

2016-01-01

Plant leaf epidermal cells exhibit a jigsaw puzzle–like pattern that is generated by interdigitation of the cell wall during leaf development. The contribution of two ROP GTPases, ROP2 and ROP6, to the cytoskeletal dynamics that regulate epidermal cell wall interdigitation has already been examined; however, how interactions between these molecules result in pattern formation remains to be elucidated. Here, we propose a simple interface equation model that incorporates both the cell wall remodeling activity of ROP GTPases and the diffusible signaling molecules by which they are regulated. This model successfully reproduces pattern formation observed in vivo, and explains the counterintuitive experimental results of decreased cellulose production and increased thickness. Our model also reproduces the dynamics of three-way cell wall junctions. Therefore, this model provides a possible mechanism for cell wall interdigitation formation in vivo. PMID:27054467

Freestyle multiple propeller flap reconstruction (jigsaw puzzle approach) for complicated back defects.

PubMed

Park, Sung Woo; Oh, Tae Suk; Eom, Jin Sup; Sun, Yoon Chi; Suh, Hyun Suk; Hong, Joon Pio

2015-05-01

The reconstruction of the posterior trunk remains to be a challenge as defects can be extensive, with deep dead space, and fixation devices exposed. Our goal was to achieve a tension-free closure for complex defects on the posterior trunk. From August 2006 to May 2013, 18 cases were reconstructed with multiple flaps combining perforator(s) and local skin flaps. The reconstructions were performed using freestyle approach. Starting with propeller flap(s) in single or multilobed design and sequentially in conjunction with adjacent random pattern flaps such as fitting puzzle. All defects achieved tensionless primary closure. The final appearance resembled a jigsaw puzzle-like appearance. The average size of defect was 139.6 cm(2) (range, 36-345 cm(2)). A total of 26 perforator flaps were used in addition to 19 random pattern flaps for 18 cases. In all cases, a single perforator was used for each propeller flap. The defect and the donor site all achieved tension-free closure. The reconstruction was 100% successful without flap loss. One case of late infection was noted at 12 months after surgery. Using multiple lobe designed propeller flaps in conjunction with random pattern flaps in a freestyle approach, resembling putting a jigsaw puzzle together, we can achieve a tension-free closure by distributing the tension to multiple flaps, supplying sufficient volume to obliterate dead space, and have reliable vascularity as the flaps do not need to be oversized. This can be a viable approach to reconstruct extensive defects on the posterior trunk. Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.

Automated surgical skill assessment in RMIS training.

PubMed

Zia, Aneeq; Essa, Irfan

2018-05-01

Manual feedback in basic robot-assisted minimally invasive surgery (RMIS) training can consume a significant amount of time from expert surgeons' schedule and is prone to subjectivity. In this paper, we explore the usage of different holistic features for automated skill assessment using only robot kinematic data and propose a weighted feature fusion technique for improving score prediction performance. Moreover, we also propose a method for generating 'task highlights' which can give surgeons a more directed feedback regarding which segments had the most effect on the final skill score. We perform our experiments on the publicly available JHU-ISI Gesture and Skill Assessment Working Set (JIGSAWS) and evaluate four different types of holistic features from robot kinematic data-sequential motion texture (SMT), discrete Fourier transform (DFT), discrete cosine transform (DCT) and approximate entropy (ApEn). The features are then used for skill classification and exact skill score prediction. Along with using these features individually, we also evaluate the performance using our proposed weighted combination technique. The task highlights are produced using DCT features. Our results demonstrate that these holistic features outperform all previous Hidden Markov Model (HMM)-based state-of-the-art methods for skill classification on the JIGSAWS dataset. Also, our proposed feature fusion strategy significantly improves performance for skill score predictions achieving up to 0.61 average spearman correlation coefficient. Moreover, we provide an analysis on how the proposed task highlights can relate to different surgical gestures within a task. Holistic features capturing global information from robot kinematic data can successfully be used for evaluating surgeon skill in basic surgical tasks on the da Vinci robot. Using the framework presented can potentially allow for real-time score feedback in RMIS training and help surgical trainees have more focused training.

The Jigsaw Earth--Putting the Pieces Together.

ERIC Educational Resources Information Center

Glenn, William H.

1983-01-01

Discusses continental drift, sea floor spreading, evidence for these two geological phenomena, and how they were unified into a theory of plate tectonics. Also discusses three types of plate boundaries: (1) divergent junctions, (2) convergent junctions, and (3) shear junctions. (Author/JN)

Negotiating Gene Therapy: Controversies

ERIC Educational Resources Information Center

Sadler, Troy; Zeidler, Dana L.

2004-01-01

According to research, students often perceive the ethical implications of issues such as genetic engineering, but sometimes they are not equipped to handle multiple perspectives and articulate well-reasoned positions. A modified jigsaw activity, appropriate for secondary and introductory college biology classes, that introduces students to human…

Better Seals for Vacuum Bags

NASA Technical Reports Server (NTRS)

Penn, B.; Clemons, J. M.

1983-01-01

Roller tool spreads even layer of adhesive. Tool easily constructed from metal, plastic, or wood. Sewing-thread spool serves as roller, nail as axle, and jigsawed block of wood as handle. Tool rolled and pressed against plastic film to assure even layer of adhesive around periphery.

Teaching Engineering with Autonomous Learning Activities

ERIC Educational Resources Information Center

Otero, Beatriz; Rodríguez, Eva; Royo, Pablo

2015-01-01

This paper proposes several activities that encourage self-learning in engineering courses. For each activity, the context and the pedagogical issues addressed are described emphasizing strengths and weaknesses. Specifically, this work describes and implements five activities, which are: questionnaires, conceptual maps, videos, jigsaw and…

Latent class analysis of need descriptors within an Irish youth mental health early intervention program toward a typology of need.

PubMed

Peiper, Nicholas; Illback, Robert J; O'Reilly, Aileen; Clayton, Richard

2017-02-01

Significant overlap and comorbidity has been demonstrated among young people with mental health problems. This paper examined demographic characteristics, heterogeneity of need descriptors and services provided among young people (12-25 years) engaging in brief interventions at Jigsaw in the Republic of Ireland. Between 1 January 2013 and 31 December 2013, a total of 2571 young people sought help from 1 of 10 Jigsaw sites. Of these, 1247 engaged in goal-focused brief interventions, typically consisting of one to six face-to-face sessions. Descriptive statistics were used to summarize social and demographic factors. Latent class analysis was used to cluster young people into relevant typologies of presenting issues. Multinomial logistic regression was then performed to determine significant predictors of class membership. The most common age of young people was 16. More women (59.6%) than men engaged in brief interventions, 56% attended school, 74% lived with their family of origin or with one parent, and 54.2% came from families where parents were married. Using established fit criteria, four relevant typologies emerged: Developmental (26.8%), Comorbid (15.8%), Anxious (42.7%) and Externalising (14.6%). Predictors varied by class membership, but general family problems and lack of adult support emerged as the strongest predictors for all classes. This study demonstrated that the mental health needs of young people in Ireland are significant and diverse. Because Jigsaw favours a more descriptive approach to problem identification, the four typologies suggest a need to determine program capacity in engaging youth with heterogeneous presenting issues and to tailor brief interventions to each group's clinical profiles. © 2015 Wiley Publishing Asia Pty Ltd.

Effects of age and type of picture on visuospatial working memory assessed with a computerized jigsaw-puzzle task.

PubMed

Toril, Pilar; Reales, José M; Mayas, Julia; Ballesteros, Soledad

2017-09-15

We investigated the effect of age and color in a computerized version of the jigsaw-puzzle task. In Experiment 1, young and older adults were presented with puzzles in color and black-and-white line drawings, varying in difficulty from 4 to 9 pieces. Older adults performed the task better with the black-and-white stimuli and younger adults performed better with the color ones. In Experiment 2, new older and young adults identified the same fragmented pictures as fast and accurately as possible. The older group identified the black-and-white stimuli faster than those presented in color, while the younger adults identified both similarly. In Experiment 3A, new older and young groups performed the puzzle task with the same color pictures and their monochrome versions. In Experiment 3B, participants performed a speeded identification task with the two sets. The findings of these experiments showed that older adults have a memory not a perceptual difficulty.

Solving the "Personhood Jigsaw Puzzle" in Residential Care Homes for the Elderly in the Hong Kong Chinese Context.

PubMed

Kong, Sui-Ting; Fang, Christine Meng-Sang; Lou, Vivian W Q

2017-02-01

End-of-life care studies on the nature of personhood are bourgeoning; however, the practices utilized for achieving personhood in end-of-life care, particularly in a cultural context in which interdependent being and collectivism prevail, remain underexplored. This study seeks to examine and conceptualize good practices for achieving the personhood of the dying elderly in residential care homes in a Chinese context. Twelve interviews were conducted with both medical and social care practitioners in four care homes to collect narratives of practitioners' practices. Those narratives were utilized to develop an "end-of-life case graph." Constant comparative analysis led to an understanding of the practice processes, giving rise to a process model of "solving the personhood jigsaw puzzle" that includes "understanding the person-in-relationship and person-in-time," "identifying the personhood-inhibiting experiences," and "enabling personalized care for enhanced psychosocial outcomes." Findings show how the "relational personhood" of the elderly can be maintained when physical deterioration and even death are inevitable.

Restitution of Sculptural Groups Using 3D Scanners

PubMed Central

Merchán, Pilar; Salamanca, Santiago; Adán, Antonio

2011-01-01

Imagine for a moment that you have to solve a 3D jigsaw of which you have lost several pieces. You have also lost the original box-top showing the final picture, and as if that were not enough, some of the pieces you do have may belong to some other jigsaw. This is in essence the sort of challenge that we faced in the novel project that we shall be describing in this paper. The final aim of the project was, with the help of 3D scanners, to digitalize and reconstruct multi-piece classical sculptures. Particularly, we tackle the restitution of the so-called “Aeneas Group”, a famous iconographic reference during the Roman Empire. We have undertaken this ambitious project in collaboration with the research department of the Spanish National Museum of Roman Art (MNAR). This paper summarizes the real problems that arose and had to be solved, the innovations, and the main results of the work that we have carried out over these recent years. PMID:22164088

Fitting the Jigsaw of Citation: Information Visualization in Domain Analysis.

ERIC Educational Resources Information Center

Chen, Chaomei; Paul, Ray J.; O'Keefe, Bob

2001-01-01

Discusses the role of information visualization in modeling and representing intellectual structures associated with scientific disciplines and visualizes the domain of computer graphics based on bibliographic data from author cocitation patterns. Highlights include author cocitation maps, citation time lines, animation of a high-dimensional…

Continental Jigsaw.

ERIC Educational Resources Information Center

Oringer, Richard H.

1985-01-01

The article outlines an activity for providing a hands-on opportunity for elementary and middle school science students to study the theory of the earth's crustal change over the past several hundred million years. The theory of continents drifting away from one super continent is presented with the supportive evidence that scientists have…

Comparison of the Effect of Addition of Cyanoacrylate, Epoxy Resin, and Gum Arabic on Surface Hardness of Die Stone.

PubMed

Tripathi, Arvind; Gupta, Ashutosh; Bagchi, Soumyojeet; Mishra, Lallan; Gautam, Abhina; Madhok, Riti

2016-04-01

To observe the effects of incorporating cyanoacrylate, epoxy resins, and gum arabic on the abrasion resistance of type IV gypsum die materials. Forty specimens were prepared and divided into four groups (10 specimens in each group), namely group A (control), group B (die stone mixed with cyanoacrylate), group C (die stone mixed with epoxy resin), group D (die stone mixed with gum arabic). All the specimens were subjected to abrasion testing, wear volume analysis, Fourier transform infrared spectroscopy (FT-IR), and scanning electron microscope (SEM) analysis. Abrasion testing showed maximum wear in the control group and minimum wear in the gum arabic group. Intergroup differences were statistically significant (p < 0.001). The largest mean difference was between control and gum arabic. The lowest was between cyanoacrylate and the control group. The mean wear volume was lowest in the gum arabic group (4.23 mm(3) ) and highest in the control group (6.78 mm(3) ). The FT-IR graphs of the gum arabic models showed the presence of CH2 , which is responsible for its binding activity. SEM revealed that the irregular particles of gum arabic display an interlocking arrangement. This jigsaw puzzle pattern results in stronger physical bond formation. Observations from this study showed that the addition of gum arabic increases resistance to abrasion in type IV gypsum. Cyanoacrylates are good adhesives as well, but a major drawback is that they have very low resistance to chemical action with water and physical actions such as sunlight. Epoxy resins are powerful adhesives, but they attain their full efficiency when cured with heat. Cyanoacrylate and epoxy resin displayed poor physical bonding, primarily because of inhomogeneity. © 2015 by the American College of Prosthodontists.

Plastics in Our Environment: A Jigsaw Learning Activity

ERIC Educational Resources Information Center

Hampton, Elaine; Wallace, Mary Ann; Lee, Wen-Yee

2009-01-01

In this lesson, a ready-to-teach cooperative reading activity, students learn about the effects of plastics in our environment, specifically that certain petrochemicals act as artificial estrogens and impact hormonal activities. Much of the content in this lesson was synthesized from recent medical research about the impact of xenoestrogens and…

A Cooperative Approach To Teaching Mineral Identification.

ERIC Educational Resources Information Center

Constantopoulos, Terri Lynn

1994-01-01

Describes Jigsaw Teaching, a cooperative learning approach, in relation to mineral identification. This technique may also be applied to rock identification. Students work in groups of four and learn to identify 20 minerals, becoming an "expert" on five of them. Helping to teach other students reinforces what each student has learned.…

ALTERNATIVE FUTURES AS AN INTEGRATIVE FRAMEWORK FOR RIPARIAN RESTORATION OF LARGE RIVERS

EPA Science Inventory

In many ways, planning landscapes with restoration goals in mind is like solving a spatial jigsaw puzzle. The choice of which piece to restore first will influence later choices, because the characteristics of remaining pieces assist the decision make in creating an emerging pic...

Medicare locals. 42+ pieces in the primary health care reform puzzle.

PubMed

Dragon, Natalie

2011-02-01

A central piece of federal Labor's health reform jigsaw is the establishment of primary health care organisations, or Medicare Locals. With much-awaited draft boundaries finally released for consultation in late 2010, there has been widespread debate about how these organisations will work on the ground.

Science Galls Me: What Is a Niche Anyway?

ERIC Educational Resources Information Center

Halverson, Kristy Lynn; Lankford, Deanna Marie

2009-01-01

The authors have developed a lesson to investigate basic principles of ecology, more specifically niche partitioning, while using a jigsaw activity that explores galling insects' interactions with goldenrods. Not only does this lesson capture secondary students' interest and keeps them engaged in hands-on activities, the content addresses two…

Distributed Collaborative Homework Activities in a Problem-Based Usability Engineering Course

ERIC Educational Resources Information Center

Carroll, John M.; Jiang, Hao; Borge, Marcela

2015-01-01

Teams of students in an upper-division undergraduate Usability Engineering course used a collaborative environment to carry out a series of three distributed collaborative homework assignments. Assignments were case-based analyses structured using a jigsaw design; students were provided a collaborative software environment and introduced to a…

The Australian-Ness of Curriculum Jigsaws: Where Does Environmental Education Fit?

ERIC Educational Resources Information Center

Gough, Annette

2011-01-01

This paper reviews Australian Government actions related to environmental education, particularly in the past decade, and examines the actions forthcoming from two national action plans (Environment Australia, 2000 and DEWHA, 2009), the implementation strategy for the Decade of ESD (DEWHA, 2006) and developments related to the Australian…

Piecing Together the "Workplace Multilingualism" Jigsaw Puzzle

ERIC Educational Resources Information Center

Hua, Zhu

2014-01-01

Multilingualism in the workplace is different from multilingualism at home or in other domains of social life. It has more direct, yet entangled, economic and social implications and serves interactional purposes which can be at any point on the continuum of goal-orientation and relationship-building. Multilingualism in the workplace is both a…

Employability and Employers: The Missing Piece of the Jigsaw. IES Report 361.

ERIC Educational Resources Information Center

Tamkin, P.; Hillage, J.

The approaches to employability being taken by United Kingdom employers were examined in a study that included three components: a literature review to develop a definition of employability and isolate its key elements; case studies of six organizations to identify employers' approaches to employability; and examination of related literature on…

Asian American Parents' Attributions of Children with Down Syndrome: Connections with Child Characteristics and Culture

ERIC Educational Resources Information Center

Ly, Tran M.

2008-01-01

This study explores cultural differences between European American (n = 26) and Asian American (n = 17) parents' attributional ratings of children with Down syndrome. Links were examined among parents' attributions, reactions, and behaviors regarding their child's jigsaw-puzzle performance. Although the children's puzzle abilities did not differ,…

Fostering Collaborative Learning in Second Life: Metaphors and Affordances

ERIC Educational Resources Information Center

Andreas, Konstantinidis; Tsiatsos, Thrasyvoulos; Terzidou, Theodouli; Pomportsis, Andreas

2010-01-01

In this paper we examine the transferability of the Jigsaw and Fishbowl collaborative learning techniques to the Second Life platform. Our aim is to assess the applicability of Second Life for collaborative learning by developing virtual tools and metaphors and exploiting the representational richness of this novel medium. In order to enhance the…

Technology-Supported Orchestration Matters: Outperforming Paper-Based Scripting in a Jigsaw Classroom

ERIC Educational Resources Information Center

Balestrini, Mara; Hernandez-Leo, Davinia; Nieves, Raul; Blat, Josep

2014-01-01

Under the umbrella of ubiquitous technologies, many computational artifacts have been designed to enhance the learning experience in physical settings such as classrooms or playgrounds, but few of them focus on aiding orchestration. This paper presents a systematic evaluation of the signal orchestration system (SOS) used by students for a jigsaw…

Pavement cells and the topology puzzle.

PubMed

Carter, Ross; Sánchez-Corrales, Yara E; Hartley, Matthew; Grieneisen, Verônica A; Marée, Athanasius F M

2017-12-01

D'Arcy Thompson emphasised the importance of surface tension as a potential driving force in establishing cell shape and topology within tissues. Leaf epidermal pavement cells grow into jigsaw-piece shapes, highly deviating from such classical forms. We investigate the topology of developing Arabidopsis leaves composed solely of pavement cells. Image analysis of around 50,000 cells reveals a clear and unique topological signature, deviating from previously studied epidermal tissues. This topological distribution is established early during leaf development, already before the typical pavement cell shapes emerge, with topological homeostasis maintained throughout growth and unaltered between division and maturation zones. Simulating graph models, we identify a heuristic cellular division rule that reproduces the observed topology. Our parsimonious model predicts how and when cells effectively place their division plane with respect to their neighbours. We verify the predicted dynamics through in vivo tracking of 800 mitotic events, and conclude that the distinct topology is not a direct consequence of the jigsaw piece-like shape of the cells, but rather owes itself to a strongly life history-driven process, with limited impact from cell-surface mechanics. © 2017. Published by The Company of Biologists Ltd.

Tracking the formation of eumelanin from L-Dopa using coupled measurements

NASA Astrophysics Data System (ADS)

Yip, Philip; Sutter, Jens U.

2018-04-01

Melanin plays a crucial role as a pigment all through the animal kingdom. Being a macromolecule just on the divide between an ordered crystalline or a purely amorphous form melanin has proven a challenge to structure-function analysis. Melanin assembles from small molecules much like a jigsaw and much like in a jigsaw the fine detail quickly vanishes in the overall picture. With melanin being first and foremost a photo-active molecule we focus on spectral properties for the characterisation of its structure. We use absorption measurements to illustrate the complex nature of the formation process. To gain a better hold on the formation pathway we use coupled measurements of excitation and emission to identify ‘areas of interest’ in the excitation-emission matrix (EEM). We then probe one area for characteristic fluorescence lifetimes to track one melanin building block through the formation process. Comparison of the EEMs of L-Dopa derived melanin with natural Sepia melanin shows characteristic differences. We show how the presence of copper ions creates a melanin closer to its natural form.

Probing compressed mass spectra in electroweak supersymmetry with Recursive Jigsaw Reconstruction

NASA Astrophysics Data System (ADS)

Santoni, M.

2018-05-01

The lack of evidence for the production of colored supersymmetric particles at the LHC has increased interest in searches for superpartners of the electroweak SM gauge bosons, namely the neutralinos and charginos. These are challenging due to the weak nature of the production process, and the existing discovery reach has significant gaps in due to the difficulty of separating the supersymmetric signal from SM diboson events that produce similar final states and kinematics. We apply the Recursive Jigsaw Reconstruction technique to study final states enriched in charged leptons and missing transverse momentum, focusing on compressed topologies with direct production of charginos and neutralinos decaying to the lightest neutral supersymmetric particle through the emission of W and Z bosons. After presenting prototype analysis designs for future LHC runs, we demonstrate that its detectors have the potential to probe a significant amount of unexplored parameter space for chargino-neutralino associated production within the next few years, and show that the very challenging successful search for chargino pair production with compressed spectra might be possible by the end of the LHC lifetime.

Pavement cells and the topology puzzle

PubMed Central

2017-01-01

D'Arcy Thompson emphasised the importance of surface tension as a potential driving force in establishing cell shape and topology within tissues. Leaf epidermal pavement cells grow into jigsaw-piece shapes, highly deviating from such classical forms. We investigate the topology of developing Arabidopsis leaves composed solely of pavement cells. Image analysis of around 50,000 cells reveals a clear and unique topological signature, deviating from previously studied epidermal tissues. This topological distribution is established early during leaf development, already before the typical pavement cell shapes emerge, with topological homeostasis maintained throughout growth and unaltered between division and maturation zones. Simulating graph models, we identify a heuristic cellular division rule that reproduces the observed topology. Our parsimonious model predicts how and when cells effectively place their division plane with respect to their neighbours. We verify the predicted dynamics through in vivo tracking of 800 mitotic events, and conclude that the distinct topology is not a direct consequence of the jigsaw piece-like shape of the cells, but rather owes itself to a strongly life history-driven process, with limited impact from cell-surface mechanics. PMID:29084800

Two coarse pyroclastic flow deposits, northern Mono-Inyo Craters, CA

NASA Astrophysics Data System (ADS)

Dennen, R. L.; Bursik, M. I.; Stokes, P. J.; Lagamba, M.; Fontanella, N.; Hintz, A. R.; Jayko, A. S.

2010-12-01

The ~1350 A.D., rhyolitic North Mono eruption, Mono-Inyo Craters, CA, included the extrusion and destruction of Panum Dome and associated clastic deposits. Overlying the tephras of the North Mono sequence, the Panum deposits include a block-and-ash flow (BAF) deposit, covering ~3.5 km2. Blocks within the deposit are typically lithic rhyolite and banded gray micro-vesicular glass, showing white, almost powdery marks ranging from circular to linear in shape. These marks are interpreted as friction marks resulting from collisions between clasts. The deposit also contains bread-crusted obsidians with pressed-in clasts as well as reticulite with a bread-crusted surface texture. Near the centerline of the deposit is a ridge-topping train of jigsaw fractured blocks, often with reddish-orange alteration. One house sized jigsaw block sits upstream of a long, thinning pile of reddish orange debris; this “flow shadow” indicates that the block remained relatively stationary while the block and ash flow continued to propagate around it. The bread-crusted reticulite is most common at proximal localities. It is proposed that the dome destruction included a debris avalanche emplacing the train of jigsaw fractured blocks and creating a topographic high, the block-and-ash flow (the farthest reaching deposit from this event) which flowed around the debris avalanche deposits, and a final “lateral expansion” of a magma foam, creating the reticulite seen concentrated at proximal locations. Another coarse pyroclastic flow (here termed the “lower blast deposit”) underlies the North Mono tephra. It is more obsidian rich and finer grained than the Panum BAF. The lower blast deposit may have originated from Pumice Pit vent, which is now capped with an older dome ~0.5 km southeast of Panum. The lower blast deposit extends farther from the Panum vent than does the Panum BAF deposit, and apparently was mistaken for the Panum BAF deposit by previous workers. Hence the run-out distance of the Panum BAF is smaller than previously reported. Thus, there are multiple, coarse pyroclastic flow-like deposits at the northern end of the Mono-Inyo Craters, reflecting multiple phases of dome destruction. The lower blast deposit is proposed to be a blast event predating the Panum eruption, possibly originating from Pumice Pit. The Panum BAF consists of three main facies, formed by three separate, sequential events. A debris avalanche deposited a train of jigsaw clasts along a narrow path, followed by a block and ash flow that spread material over a wider region. Finally, molten rhyolite was exposed by the earlier events, resulting in rapid foam expansion and creation of a bread crusted reticulite-bearing facies.

A Jigsaw Cooperative Learning Application in Elementary Science and Technology Lessons: Physical and Chemical Changes

ERIC Educational Resources Information Center

Tarhan, Leman; Ayyildiz, Yildizay; Ogunc, Aylin; Sesen, Burcin Acar

2013-01-01

Background: Cooperative learning is an active learning approach in which students work together in small groups to complete an assigned task. Students commonly find the subject of "physical and chemical changes" difficult and abstract, and thus they generally have many misconceptions about it. Purpose: This study aimed to investigate the…

Historical jigsaw puzzles: piecing together the understory of Garry Oak (Quercus garryana) ecosystems and the implications for restoration

Treesearch

Carrina Maslovat

2002-01-01

Ecosystem restoration requires a set of reference vegetation conditions which are difficult to find for Garry oak (Quercus garryana) ecosystems in Canada because contemporary sites have been drastically altered. A survey of historical information provides only limited clues about the original understory vegetation. Although there is considerable...

Assembling the Arts Education Jigsaw

ERIC Educational Resources Information Center

Blakeslee, Michael

2004-01-01

In this paper, the author explains why programs or potential programs designed to serve education in music and the other arts should be evaluated on the basis of breadth of coverage of standards-based skill and knowledge, of depth of coverage of that skill and knowledge and on the proportion of a given student population that they reach. Those who…

Effects of Cooperative Learning on Students at An Giang University in Vietnam

ERIC Educational Resources Information Center

Tran, Van Dat; Lewis, Ramon

2012-01-01

This study investigates the effects of jigsaw cooperative learning on the achievement and knowledge retention of 80 final-year Vietnamese mathematics students, as well as reporting their attitudes toward this form of learning. These tertiary students were divided into two matched groups of 40 to be taught by the same lecturer. In the experimental…

Classroom Teacher's Idea Notebook: Try Trivia for Openers.

ERIC Educational Resources Information Center

Marran, James F.; And Others

1988-01-01

Presents three activities suitable for junior/senior high school social studies. The first demonstrates the use of trivia as a springboard into a lesson, the second shows how a scavenger hunt can be used to teach social studies content, and the third describes a 1-3 day procedure for teaching a jigsaw lesson on modernization in Meiji Japan. (GEA)

Interactive Distance e-Learning for Isolated Communities: Starting and Finishing the Jigsaw

ERIC Educational Resources Information Center

Crump, Stephen; Boylan, Colin

2008-01-01

This paper provides information on the background to the two pilot investigations into "interactive distance e-learning" [IDeL] following the introduction in New South Wales and in the Northern Territory of Australia of satellite-supported two-way broad-band internet services for school-age and adult distance education. The context is…

Excitation of Standing Waves by an Electric Toothbrush

ERIC Educational Resources Information Center

Cros, Ana; Ferrer-Roca, Chantal

2006-01-01

There are a number of ways of exciting standing waves in ropes and springs using non-commercial vibrators such as loudspeakers, jigsaws, motors, or a simple tuning fork, including the rhythmical shaking of a handheld Slinky. We have come up with a very simple and cheap way of exciting stationary waves in a string, which anyone, particularly…

Welcome In! How the Academy Can Warrant Recognition of Young Children as Researchers

ERIC Educational Resources Information Center

Murray, Jane

2017-01-01

The academy has tended to marginalise young children as researchers (YCAR), even in matters affecting them, which denies young children agency and amounts to social injustice. Drawing on the YCAR study, which adopted a qualitative "jigsaw" methodology to co-research with children aged four to eight years (n = 138), their parents,…

Jigsaw Research Communities: Coordinating Research and Service across Multiple Courses to Serve a Single Community Partner

ERIC Educational Resources Information Center

Cross, Anne; Eckberg, Deborah A.

2015-01-01

This article describes a public scholarship project in which two faculty members worked together to integrate service-learning and research into multiple courses to benefit a single community partner. The project linked undergraduate students, graduate students, and faculty in a broad-based research endeavor that contributed to the survival and…

The Effects of Communication Mode on Negotiation of Meaning and Its Noticing

ERIC Educational Resources Information Center

Yuksel, Dogan; Inan, Banu

2014-01-01

This study examined the effects of communication mode ("i.e.", face to face versus computer mediated communication) on the instances of negotiation of meaning (NofM) and its level of noticing by learners. Sixty-four participants (32 dyads) completed two jigsaw tasks in two different mediums (one in each) and four days after the tasks…

Researching the Pieces of a Puzzle: The Use of a Jigsaw Learning Approach in the Delivery of Undergraduate Gymnastics

ERIC Educational Resources Information Center

O'Leary, Nicholas; Griggs, Gerald

2010-01-01

There have been strengthening recommendations that physical education (PE) should make a wider contribution to learning beyond that of psychomotor development. Cooperative learning models show considerable potential for study in PE but as yet these remain unexplored. This article reports upon an undergraduate gymnastics programme delivered using a…

Effect of Jigsaw Technique and Gender on Students' Attitude to Ethnic Integration and Sustainable Development in Nigeria

ERIC Educational Resources Information Center

Olukayode, Ajitoni Sunday; Salako, Ekima Tina

2014-01-01

The growing spate of ethno-religious crises and insurgency that characterizes Nigerian polity has been traced to inadequacies in the integration policies of the government. These situations have resulted in loss of several lives and unquantifiable psychological and material damages. However, the situations could improve through the use of…

The Amazing Animal Activity Book: Dozens of Hands-on Projects That Teach across the Curriculum. Grades 1-3.

ERIC Educational Resources Information Center

Bernard, Robin

The activities in this book are designed to encourage children's scientific curiosity as well as their creativity. Activities include puppet making, word scrambles, matching exercises, crossword and jigsaw puzzles, mobiles, games, mini books, coloring activities, Venn diagrams, and plays. These activities are intended as a foundation for children…

Cooperative Learning Model toward a Reading Comprehensions on the Elementary School

ERIC Educational Resources Information Center

Murtono

2015-01-01

The purposes of this research are: (1) description of reading skill the students who join in CIRC learning model, Jigsaw learning model, and STAD learning model; (2) finding out the effective of learning model cooperative toward a reading comprehensions between the students who have high language logic and low language logic; and (3) finding out…

On the validity of Freud's dream interpretations.

PubMed

Michael, Michael

2008-03-01

In this article I defend Freud's method of dream interpretation against those who criticize it as involving a fallacy-namely, the reverse causal fallacy-and those who criticize it as permitting many interpretations, indeed any that the interpreter wants to put on the dream. The first criticism misconstrues the logic of the interpretative process: it does not involve an unjustified reversal of causal relations, but rather a legitimate attempt at an inference to the best explanation. The judgement of whether or not a particular interpretation is the best explanation depends on the details of the case in question. I outline the kinds of probabilities involved in making the judgement. My account also helps to cash out the metaphors of the jigsaw and crossword puzzles that Freudians have used in response to the 'many interpretations' objection. However, in defending Freud's method of dream interpretation, I do not thereby defend his theory of dreams, which cannot be justified by his interpretations alone.

Geography Map Knowledge Acquisition by Solving a Jigsaw Map Compared to Self-Study: Investigating Game Based Learning

ERIC Educational Resources Information Center

Dang, Srishti; Ved, Arunima; Vemuri, Kavita

2018-01-01

Efficacy of games as learning medium is of interest to researchers and the gaming industry. A critical metric for learning is knowledge retention and very few studies have conducted in-depth comparisons of: a) game versus no-game learning, b) collaborative versus individual learning. Towards this, the study reported in this article will present…

Comparison of Two Different Techniques of Cooperative Learning Approach: Undergraduates' Conceptual Understanding in the Context of Hormone Biochemistry

ERIC Educational Resources Information Center

Mutlu, Ayfer

2018-01-01

The purpose of the research was to compare the effects of two different techniques of the cooperative learning approach, namely Team-Game Tournament and Jigsaw, on undergraduates' conceptual understanding in a Hormone Biochemistry course. Undergraduates were randomly assigned to Group 1 (N = 23) and Group 2 (N = 29). Instructions were accomplished…

The Advantages of Repeat Interviews in a Study with Pregnant Schoolgirls and Schoolgirl Mothers: Piecing Together the Jigsaw

ERIC Educational Resources Information Center

Vincent, Kerry Anne

2013-01-01

Qualitative interviewing is a commonly used approach in the social sciences and is generally regarded as an effective way of developing understandings about everyday experiences and the meanings people attach to them. Where fieldwork time-frames are relatively short, a single interview with each participant is common. This paper explores the…

Attitude of Students towards Cooperative Learning in Some Selected Secondary Schools in Nasarawa State

ERIC Educational Resources Information Center

Amedu, Odagboyi Isaiah; Gudi, Kreni Comfort

2017-01-01

This study is aimed at investigating the attitude of students toward the cooperative learning approach. A quasiexperimental design was used for the study. The sample was made of 179 SS 1 students drawn from three public secondary schools in Nasarawa state. The Jigsaw Attitude Questionnaire (JAQ) was adapted from Koprowski and Perigo (2000) and was…

An Initial Study of the Effects of Cooperative Learning on Reading Comprehension, Vocabulary Acquisition, and Motivation to Read

ERIC Educational Resources Information Center

Shaaban, Kassim

2006-01-01

This study investigated the effects of the Jigsaw II cooperative learning (CL) model and whole class instruction in improving learners' reading comprehension, vocabulary acquisition, and motivation to read. Forty-four grade five English as a foreign language learners participated in the study, and a posttest-only control group experimental design…

An Unfinished Jigsaw: The 16+ Curriculum in the 1990s.

ERIC Educational Resources Information Center

Kershaw, Noel

Education reform in Great Britain during the last 15 years has been piecemeal, and all the pieces are not yet in place for broad and balanced post-16 education. The last 10 years of debate have achieved much common ground among the goals perceived by government, industry, and education. Three major ways of looking at the post-16 curriculum have…

The Jigsaw Puzzle of mRNA Translation Initiation in Eukaryotes: A Decade of Structures Unraveling the Mechanics of the Process.

PubMed

Hashem, Yaser; Frank, Joachim

2018-03-01

Translation initiation in eukaryotes is a highly regulated and rate-limiting process. It results in the assembly and disassembly of numerous transient and intermediate complexes involving over a dozen eukaryotic initiation factors (eIFs). This process culminates in the accommodation of a start codon marking the beginning of an open reading frame at the appropriate ribosomal site. Although this process has been extensively studied by hundreds of groups for nearly half a century, it has been only recently, especially during the last decade, that we have gained deeper insight into the mechanics of the eukaryotic translation initiation process. This advance in knowledge is due in part to the contributions of structural biology, which have shed light on the molecular mechanics underlying the different functions of various eukaryotic initiation factors. In this review, we focus exclusively on the contribution of structural biology to the understanding of the eukaryotic initiation process, a long-standing jigsaw puzzle that is just starting to yield the bigger picture. Expected final online publication date for the Annual Review of Biophysics Volume 47 is May 20, 2018. Please see http://www.annualreviews.org/page/journal/pubdates for revised estimates.

The Effect of Two Different Cooperative Approaches on Students' Learning and Practices within the Context of a WebQuest Science Investigation

ERIC Educational Resources Information Center

Zacharia, Zacharias C.; Xenofontos, Nikoletta A.; Manoli, Constantinos C.

2011-01-01

The goal of this study was to investigate the effect of two different cooperative learning approaches, namely, the Jigsaw Cooperative Approach (JCA) and the Traditional Cooperative Approach (TCA), on students' learning and practices/actions within the context of a WebQuest science investigation. Another goal of this study was to identify possible…

Sound Evidence: The Missing Piece of the Jigsaw in Formulaic Language Research

ERIC Educational Resources Information Center

Lin, Phoebe M. S.

2012-01-01

With the ever increasing number of studies on formulaic language, we are beginning to learn more about the processing of formulaic language (e.g. Ellis et al. 2008; Siyanova et al. 2011), its use in speech (e.g. Aijmer 1996; Wood 2012) and writing (e.g. Hyland 2008a, 2008b) and its application in natural language processing (e.g. Tschichold 2000).…

Relative Effectiveness of Computer-Supported Jigsaw II, STAD and TAI Cooperative Learning Strategies on Performance, Attitude, and Retention of Secondary School Students in Physics

ERIC Educational Resources Information Center

Gambari, Amosa Isiaka; Yusuf, Mudasiru Olalere

2017-01-01

This study investigated the relative effectiveness of computer-supported cooperative learning strategies on the performance, attitudes, and retention of secondary school students in physics. A purposive sampling technique was used to select four senior secondary schools from Minna, Nigeria. The students were allocated to one of four groups:…

The Emergence of the Teaching/Learning Process in Preschoolers: Theory of Mind and Age Effect

ERIC Educational Resources Information Center

Bensalah, Leila

2011-01-01

This study analysed the gradual emergence of the teaching/learning process by examining theory of mind (ToM) acquisition and age effects in the preschool period. We observed five dyads performing a jigsaw task drawn from a previous study. Three stages were identified. In the first one, the teacher focuses on the execution of her/his own task…

The Savvy Librarian's Night Table: Ten Amazing Titles Guaranteed to Bring You Peace, Prosperity, and Happiness

ERIC Educational Resources Information Center

Genco, Barbara

2010-01-01

With so many choices and so many terrific nonfiction titles in the pipeline, picking the "right" read can be daunting. This year, the author offers a variety of choices: the future of books, the life of a great American photographer, jigsaw puzzles as a metaphor for life, the negative legacy of America's positive thinking, a history of American…

The Development of Geometri Teaching Materials Based on Constructivism to Improve the Students' Mathematic Reasoning Ability through Cooperative Learing Jigsaw at the Class VIII of SMP Negeri 3 Padangsidimpuan

ERIC Educational Resources Information Center

Dewi, Izwita; Harahap, Muhammad Syahri

2016-01-01

The purposes of this research were to know the validity, practicality, and effectivity of geometrical learning material based on the constructivism to Increase students' mathematic reasoning ability and increasing students' mathematic reasoning ability by using learning material at the grade VIII of SMP Negeri 3 Padangsidimpuan. Type of the…

Putting Together a Blue Sky: Laying the Foundation for Staff Evaluation

ERIC Educational Resources Information Center

Searcy, Jeny

2012-01-01

Evaluation time can be like putting together a 5,000-piece jigsaw puzzle that is all sky--what, exactly, is the point? When all is said and done, one ends up with a big blue blob--nothing to show for all the effort. However, it doesn't have to be that way. Performance reviews can and should be an effective means of communication for both parties…

One chromosome, one contig: complete microbial genomes from long-read sequencing and assembly.

PubMed

Koren, Sergey; Phillippy, Adam M

2015-02-01

Like a jigsaw puzzle with large pieces, a genome sequenced with long reads is easier to assemble. However, recent sequencing technologies have favored lowering per-base cost at the expense of read length. This has dramatically reduced sequencing cost, but resulted in fragmented assemblies, which negatively affect downstream analyses and hinder the creation of finished (gapless, high-quality) genomes. In contrast, emerging long-read sequencing technologies can now produce reads tens of kilobases in length, enabling the automated finishing of microbial genomes for under $1000. This promises to improve the quality of reference databases and facilitate new studies of chromosomal structure and variation. We present an overview of these new technologies and the methods used to assemble long reads into complete genomes. Copyright © 2014 The Authors. Published by Elsevier Ltd.. All rights reserved.

'You're looking for different parts in a jigsaw': foetal MRI (magnetic resonance imaging) as an emerging technology in professional practice.

PubMed

Reed, Kate; Kochetkova, Inna; Molyneux-Hodgson, Susan

2016-06-01

Magnetic resonance imaging (MRI) was first introduced into clinical practice during the 1980s. Originally used as a diagnostic tool to take pictures of the brain, spine, and joints, it is now used to visualise a range of organs and soft tissue around the body. Developments in clinical applications of the technology are rapid and it is often viewed as the 'gold standard' in many areas of medicine. However, most existing sociological work on MRI tends to focus on the profession of radiology, little is known about the impact of MRI on a broader range of clinical practice. This article focuses on MRI use in pregnancy, a relatively new application of the technology. Drawing on empirical research with a range of health professionals (from radiologists to pathologists) in the North of England, this article asks: how do different types of health professionals engage with the technology and to what end? It will argue that MRI use in pregnancy offers an increasingly important piece of the diagnostic jigsaw, often acting as a bridging technology between medical specialties. The implications of this will be explored in the context of broader sociological debates on the 'visualisation' of medicine and its impact on professionals. © 2016 The Authors. Sociology of Health & Illness published by John Wiley & Sons Ltd on behalf of Foundation for SHIL.

SCIGN; new Southern California GPS network advances the study of earthquakes

USGS Publications Warehouse

Hudnut, Ken; King, Nancy

2001-01-01

Southern California is a giant jigsaw puzzle, and scientists are now using GPS satellites to track the pieces. These puzzle pieces are continuously moving, slowly straining the faults in between. That strain is then eventually released in earthquakes. The innovative Southern California Integrated GPS Network (SCIGN) tracks the motions of these pieces over most of southern California with unprecedented precision. This new network greatly improves the ability to assess seismic hazards and quickly measure the larger displacements that occur during and immediatelyafter earthquakes.

The seismicity of Ethiopia; active plate tectonics

USGS Publications Warehouse

Mohr, P.

1981-01-01

Ethiopia, descended from the semimythical Kingdom of Punt, lies at the strategic intersection of Schmidt's jigsaw puzzle where the Red Sea, Gulf of Aden, and the African Rift System meet. Because of geologically recent uplift combined with rapid downcutting erosion by rivers, notably the Blue Nile (Abbay), Ethiopia is the most mountainous country in Africa. It is also the most volcanically active, while its historical seismicity matches that of the midocean ridges. And, in a sense, Ethiopia is host to an evoloving ocean ridge system. 

Multipath Routing of Fragmented Data Transfer in a Smart Grid Environment

NASA Astrophysics Data System (ADS)

Borgohain, Tuhin; Borgohain, Amardeep; Borgohain, Rajdeep; Sanyal, Sugata

2015-02-01

The purpose of this paper is to do a general survey on the existing communication modes inside a smart grid, the existing security loopholes and their countermeasures. Then we suggest a detailed countermeasure, building upon the Jigsaw based secure data transfer [8] for enhanced security of the data flow inside the communication system of a smart grid. The paper has been written without the consideration of any factor of inoperability between the various security techniques inside a smart grid

Instrumental variable methods in comparative safety and effectiveness research.

PubMed

Brookhart, M Alan; Rassen, Jeremy A; Schneeweiss, Sebastian

2010-06-01

Instrumental variable (IV) methods have been proposed as a potential approach to the common problem of uncontrolled confounding in comparative studies of medical interventions, but IV methods are unfamiliar to many researchers. The goal of this article is to provide a non-technical, practical introduction to IV methods for comparative safety and effectiveness research. We outline the principles and basic assumptions necessary for valid IV estimation, discuss how to interpret the results of an IV study, provide a review of instruments that have been used in comparative effectiveness research, and suggest some minimal reporting standards for an IV analysis. Finally, we offer our perspective of the role of IV estimation vis-à-vis more traditional approaches based on statistical modeling of the exposure or outcome. We anticipate that IV methods will be often underpowered for drug safety studies of very rare outcomes, but may be potentially useful in studies of intended effects where uncontrolled confounding may be substantial.

Instrumental variables vs. grouping approach for reducing bias due to measurement error.

PubMed

Batistatou, Evridiki; McNamee, Roseanne

2008-01-01

Attenuation of the exposure-response relationship due to exposure measurement error is often encountered in epidemiology. Given that error cannot be totally eliminated, bias correction methods of analysis are needed. Many methods require more than one exposure measurement per person to be made, but the `group mean OLS method,' in which subjects are grouped into several a priori defined groups followed by ordinary least squares (OLS) regression on the group means, can be applied with one measurement. An alternative approach is to use an instrumental variable (IV) method in which both the single error-prone measure and an IV are used in IV analysis. In this paper we show that the `group mean OLS' estimator is equal to an IV estimator with the group mean used as IV, but that the variance estimators for the two methods are different. We derive a simple expression for the bias in the common estimator which is a simple function of group size, reliability and contrast of exposure between groups, and show that the bias can be very small when group size is large. We compare this method with a new proposal (group mean ranking method), also applicable with a single exposure measurement, in which the IV is the rank of the group means. When there are two independent exposure measurements per subject, we propose a new IV method (EVROS IV) and compare it with Carroll and Stefanski's (CS IV) proposal in which the second measure is used as an IV; the new IV estimator combines aspects of the `group mean' and `CS' strategies. All methods are evaluated in terms of bias, precision and root mean square error via simulations and a dataset from occupational epidemiology. The `group mean ranking method' does not offer much improvement over the `group mean method.' Compared with the `CS' method, the `EVROS' method is less affected by low reliability of exposure. We conclude that the group IV methods we propose may provide a useful way to handle mismeasured exposures in epidemiology with or without replicate measurements. Our finding may also have implications for the use of aggregate variables in epidemiology to control for unmeasured confounding.

Instrumental variable methods in comparative safety and effectiveness research†

PubMed Central

Brookhart, M. Alan; Rassen, Jeremy A.; Schneeweiss, Sebastian

2010-01-01

Summary Instrumental variable (IV) methods have been proposed as a potential approach to the common problem of uncontrolled confounding in comparative studies of medical interventions, but IV methods are unfamiliar to many researchers. The goal of this article is to provide a non-technical, practical introduction to IV methods for comparative safety and effectiveness research. We outline the principles and basic assumptions necessary for valid IV estimation, discuss how to interpret the results of an IV study, provide a review of instruments that have been used in comparative effectiveness research, and suggest some minimal reporting standards for an IV analysis. Finally, we offer our perspective of the role of IV estimation vis-à-vis more traditional approaches based on statistical modeling of the exposure or outcome. We anticipate that IV methods will be often underpowered for drug safety studies of very rare outcomes, but may be potentially useful in studies of intended effects where uncontrolled confounding may be substantial. PMID:20354968

Compilation of 1985 Annual Reports of the Navy ELF (Extremely Low Frequency) Communications System Ecological Monitoring Program. Volume 1. Tabs A-C.

DTIC Science & Technology

1986-07-01

and straight when short, but spindly and often crooked when long, ususally somewhat constricted at the base. Microscopic -- Surface hyphae sparse, 2-3... hyphae with conspicuous interlocking, "jig-saw puzzle-like" pattern; cortical cells red-brown except over apex where they are colorless; Hartig net hyphae ...Type S Macroscopic -- Black, sometimes with lighter apex; usually fuzzy, with abundant attached, coarse hyphae ; 1-3 mm long X 0.5-1.0 mm diameter; mono

Patchwork plagiarism--a jigsaw of stolen puzzle pieces.

PubMed

Supak Smolcić, Vesna; Bilić-Zulle, Lidija

2013-01-01

Plagiarism remains at the top in terms of interest to the scientific community. In its many vicious forms, patchwork plagiarism is characterized by numerous unresolved issues and often passes "below the radar" of editors and reviewers. The problem of detecting the complexity of misconduct has been partially resolved by plagiarism detection software. However, interpretation of relevant reports is not always obvious or easy. This article deals with plagiarism in general and patchwork plagiarism in particular, as well as related problems that editors must deal with to maintain the integrity of scientific journals.

Classroom Activities: Simple Strategies to Incorporate Student-Centered Activities within Undergraduate Science Lectures

PubMed Central

Lom, Barbara

2012-01-01

The traditional science lecture, where an instructor delivers a carefully crafted monolog to a large audience of students who passively receive the information, has been a popular mode of instruction for centuries. Recent evidence on the science of teaching and learning indicates that learner-centered, active teaching strategies can be more effective learning tools than traditional lectures. Yet most colleges and universities retain lectures as their central instructional method. This article highlights several simple collaborative teaching techniques that can be readily deployed within traditional lecture frameworks to promote active learning. Specifically, this article briefly introduces the techniques of: reader’s theatre, think-pair-share, roundtable, jigsaw, in-class quizzes, and minute papers. Each technique is broadly applicable well beyond neuroscience courses and easily modifiable to serve an instructor’s specific pedagogical goals. The benefits of each technique are described along with specific examples of how each technique might be deployed within a traditional lecture to create more active learning experiences. PMID:23494568

Patchwork plagiarism – a jigsaw of stolen puzzle pieces

PubMed Central

Smolčić, Vesna Šupak; Bilić-Zulle, Lidija

2013-01-01

Plagiarism remains at the top in terms of interest to the scientific community. In its many vicious forms, patchwork plagiarism is characterized by numerous unresolved issues and often passes “below the radar” of editors and reviewers. The problem of detecting the complexity of misconduct has been partially resolved by plagiarism detection software. However, interpretation of relevant reports is not always obvious or easy. This article deals with plagiarism in general and patchwork plagiarism in particular, as well as related problems that editors must deal with to maintain the integrity of scientific journals. PMID:23457762

Method for decontamination of radioactive metal surfaces

DOEpatents

Bray, L.A.

1996-08-13

Disclosed is a method for removing radioactive contaminants from metal surfaces by applying steam containing an inorganic acid and cerium IV. Cerium IV is applied to contaminated metal surfaces by introducing cerium IV in solution into a steam spray directed at contaminated metal surfaces. Cerium IV solution is converted to an essentially atomized or vapor phase by the steam.

Patient-specific puzzle implant preformed with 3D-printed rapid prototype model for combined orbital floor and medial wall fracture.

PubMed

Kim, Young Chul; Min, Kyung Hyun; Choi, Jong Woo; Koh, Kyung S; Oh, Tae Suk; Jeong, Woo Shik

2018-04-01

The management of combined orbital floor and medial wall fractures involving the inferomedial strut is challenging due to absence of stable cornerstone. In this article, we proposed surgical strategies using customized 3D puzzle implant preformed with Rapid Prototype (RP) skull model. Retrospective review was done in 28 patients diagnosed with combined orbital floor and medial wall fracture. Using preoperative CT scans, original and mirror-imaged RP skull models for each patient were prepared and sterilized. In all patients, porous polyethylene-coated titanium mesh was premolded onto RP skull model in two ways; Customized 3D jigsaw puzzle technique was used in 15 patients with comminuted inferomedial strut, whereas individual 3D implant technique was used in each fracture for 13 patients with intact inferomedial strut. Outcomes including enophthalmos, visual acuity, and presence of diplopia were assessed and orbital volume was measured using OsiriX software preoperatively and postoperatively. Satisfactory results were achieved in both groups in terms of clinical improvements. Of 10 patients with preoperative diplopia, 9 improved in 6 months, except one with persistent symptom who underwent extraocular muscle rupture. 18 patients who had moderate to severe enophthalmos preoperatively improved, and one remained with mild degree. Orbital volume ratio, defined as volumetric ratio between affected and control orbit, decreased from 127.6% to 99.79% (p < 0.05) in comminuted group, and that in intact group decreased from 117.03% to 101.3% (p < 0.05). Our surgical strategies using the jigsaw puzzle and individual reconstruction technique provide accurate restoration of combined orbital floor and medial wall fractures. Copyright © 2017 British Association of Plastic, Reconstructive and Aesthetic Surgeons. Published by Elsevier Ltd. All rights reserved.

Emergence of Life on Earth: A Physicochemical Jigsaw Puzzle.

PubMed

Spitzer, Jan

2017-01-01

We review physicochemical factors and processes that describe how cellular life can emerge from prebiotic chemical matter; they are: (1) prebiotic Earth is a multicomponent and multiphase reservoir of chemical compounds, to which (2) Earth-Moon rotations deliver two kinds of regular cycling energies: diurnal electromagnetic radiation and seawater tides. (3) Emerging colloidal phases cyclically nucleate and agglomerate in seawater and consolidate as geochemical sediments in tidal zones, creating a matrix of microspaces. (4) Some microspaces persist and retain memory from past cycles, and others re-dissolve and re-disperse back into the Earth's chemical reservoir. (5) Proto-metabolites and proto-biopolymers coevolve with and within persisting microspaces, where (6) Macromolecular crowding and other non-covalent molecular forces govern the evolution of hydrophilic, hydrophobic, and charged molecular surfaces. (7) The matrices of microspaces evolve into proto-biofilms of progenotes with rudimentary but evolving replication, transcription, and translation, enclosed in unstable cell envelopes. (8) Stabilization of cell envelopes 'crystallizes' bacteria-like genetics and metabolism with low horizontal gene transfer-life 'as we know it.' These factors and processes constitute the 'working pieces' of the jigsaw puzzle of life's emergence. They extend the concept of progenotes as the first proto-cellular life, connected backward in time to the cycling chemistries of the Earth-Moon planetary system, and forward to the ancient cell cycle of first bacteria-like organisms. Supra-macromolecular models of 'compartments first' are preferred: they facilitate macromolecular crowding-a key abiotic/biotic transition toward living states. Evolutionary models of metabolism or genetics 'first' could not have evolved in unconfined and uncrowded environments because of the diffusional drift to disorder mandated by the second law of thermodynamics.

Signature neural networks: definition and application to multidimensional sorting problems.

PubMed

Latorre, Roberto; de Borja Rodriguez, Francisco; Varona, Pablo

2011-01-01

In this paper we present a self-organizing neural network paradigm that is able to discriminate information locally using a strategy for information coding and processing inspired in recent findings in living neural systems. The proposed neural network uses: 1) neural signatures to identify each unit in the network; 2) local discrimination of input information during the processing; and 3) a multicoding mechanism for information propagation regarding the who and the what of the information. The local discrimination implies a distinct processing as a function of the neural signature recognition and a local transient memory. In the context of artificial neural networks none of these mechanisms has been analyzed in detail, and our goal is to demonstrate that they can be used to efficiently solve some specific problems. To illustrate the proposed paradigm, we apply it to the problem of multidimensional sorting, which can take advantage of the local information discrimination. In particular, we compare the results of this new approach with traditional methods to solve jigsaw puzzles and we analyze the situations where the new paradigm improves the performance.

Is primary care a neglected piece of the jigsaw in ensuring optimal stroke care? Results of a national study

PubMed Central

Whitford, David L; Hickey, Anne; Horgan, Frances; O'Sullivan, Bernadette; McGee, Hannah; O'Neill, Desmond

2009-01-01

Background Stroke is a major cause of mortality and morbidity with potential for improved care and prevention through general practice. A national survey was undertaken to determine current resources and needs for optimal stroke prevention and care. Methods Postal survey of random sample of general practitioners undertaken (N = 204; 46% response). Topics included practice organisation, primary prevention, acute management, secondary prevention, long-term care and rehabilitation. Results Service organisation for both primary and secondary prevention was poor. Home management of acute stroke patients was used at some stage by 50% of responders, accounting for 7.3% of all stroke patients. Being in a structured cardiovascular management scheme, a training practice, a larger practice, or a practice employing a practice nurse were associated with structures and processes likely to support stroke prevention and care. Conclusion General practices were not fulfilling their potential to provide stroke prevention and long-term management. Systems of structured stroke management in general practice are essential to comprehensive national programmes of stroke care. PMID:19402908

From CBCL to DSM: A Comparison of Two Methods to Screen for DSM-IV Diagnoses Using CBCL Data

ERIC Educational Resources Information Center

Krol, Nicole P. C. M.; De Bruyn, Eric E. J.; Coolen, Jolanda C.; van Aarle, Edward J. M.

2006-01-01

The screening efficiency of 2 methods to convert Child Behavior Checklist (CBCL) assessment data into Diagnostic and Statistical Manual of Mental Disorders (4th ed. [DSM-IV]; American Psychiatric Association, 1994) diagnoses was compared. The Machine-Aided Diagnosis (MAD) method converts CBCL input data directly into DSM-IV symptom criteria. The…

Factors influencing the academic motivation of individual college students.

PubMed

Yoshida, Masahiro; Tanaka, Masaaki; Mizuno, Kei; Ishii, Akira; Nozaki, Kumi; Urakawa, Ayako; Cho, Yuki; Kataoka, Yosky; Watanabe, Yasuyoshi

2008-10-01

Motivation is an important psychological concept in academic learning. Subjects performed jigsaw puzzle and square puzzle sessions (as difficulty variant task) and 80%, 50%, and 20% completion sessions (as completion variant task). After square puzzle or 20% completion sessions, subjective motivation decreased. Although baseline scores on an academic motivation scale were negatively correlated with changes in subjective motivation for the square puzzle session, a positive correlation was observed for the 20% completion session. These suggest that while continual completion of facile task trials may support the motivation of college students with lower academic motivation, attempting difficult task trials may sustain that of those with higher academic motivation.

Development of Methodologies for IV and V of Neural Networks

NASA Technical Reports Server (NTRS)

Taylor, Brian; Darrah, Marjorie

2003-01-01

Non-deterministic systems often rely upon neural network (NN) technology to "lean" to manage flight systems under controlled conditions using carefully chosen training sets. How can these adaptive systems be certified to ensure that they will become increasingly efficient and behave appropriately in real-time situations? The bulk of Independent Verification and Validation (IV&V) research of non-deterministic software control systems such as Adaptive Flight Controllers (AFC's) addresses NNs in well-behaved and constrained environments such as simulations and strict process control. However, neither substantive research, nor effective IV&V techniques have been found to address AFC's learning in real-time and adapting to live flight conditions. Adaptive flight control systems offer good extensibility into commercial aviation as well as military aviation and transportation. Consequently, this area of IV&V represents an area of growing interest and urgency. ISR proposes to further the current body of knowledge to meet two objectives: Research the current IV&V methods and assess where these methods may be applied toward a methodology for the V&V of Neural Network; and identify effective methods for IV&V of NNs that learn in real-time, including developing a prototype test bed for IV&V of AFC's. Currently. no practical method exists. lSR will meet these objectives through the tasks identified and described below. First, ISR will conduct a literature review of current IV&V technology. TO do this, ISR will collect the existing body of research on IV&V of non-deterministic systems and neural network. ISR will also develop the framework for disseminating this information through specialized training. This effort will focus on developing NASA's capability to conduct IV&V of neural network systems and to provide training to meet the increasing need for IV&V expertise in such systems.

Instrumental Variable Methods for Continuous Outcomes That Accommodate Nonignorable Missing Baseline Values.

PubMed

Ertefaie, Ashkan; Flory, James H; Hennessy, Sean; Small, Dylan S

2017-06-15

Instrumental variable (IV) methods provide unbiased treatment effect estimation in the presence of unmeasured confounders under certain assumptions. To provide valid estimates of treatment effect, treatment effect confounders that are associated with the IV (IV-confounders) must be included in the analysis, and not including observations with missing values may lead to bias. Missing covariate data are particularly problematic when the probability that a value is missing is related to the value itself, which is known as nonignorable missingness. In such cases, imputation-based methods are biased. Using health-care provider preference as an IV method, we propose a 2-step procedure with which to estimate a valid treatment effect in the presence of baseline variables with nonignorable missing values. First, the provider preference IV value is estimated by performing a complete-case analysis using a random-effects model that includes IV-confounders. Second, the treatment effect is estimated using a 2-stage least squares IV approach that excludes IV-confounders with missing values. Simulation results are presented, and the method is applied to an analysis comparing the effects of sulfonylureas versus metformin on body mass index, where the variables baseline body mass index and glycosylated hemoglobin have missing values. Our result supports the association of sulfonylureas with weight gain. © The Author 2017. Published by Oxford University Press on behalf of the Johns Hopkins Bloomberg School of Public Health. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Robust Requirements Tracing via Internet Search Technology: Improving an IV and V Technique. Phase 2

NASA Technical Reports Server (NTRS)

Hayes, Jane; Dekhtyar, Alex

2004-01-01

There are three major objectives to this phase of the work. (1) Improvement of Information Retrieval (IR) methods for Independent Verification and Validation (IV&V) requirements tracing. Information Retrieval methods are typically developed for very large (order of millions - tens of millions and more documents) document collections and therefore, most successfully used methods somewhat sacrifice precision and recall in order to achieve efficiency. At the same time typical IR systems treat all user queries as independent of each other and assume that relevance of documents to queries is subjective for each user. The IV&V requirements tracing problem has a much smaller data set to operate on, even for large software development projects; the set of queries is predetermined by the high-level specification document and individual requirements considered as query input to IR methods are not necessarily independent from each other. Namely, knowledge about the links for one requirement may be helpful in determining the links of another requirement. Finally, while the final decision on the exact form of the traceability matrix still belongs to the IV&V analyst, his/her decisions are much less arbitrary than those of an Internet search engine user. All this suggests that the information available to us in the framework of the IV&V tracing problem can be successfully leveraged to enhance standard IR techniques, which in turn would lead to increased recall and precision. We developed several new methods during Phase II; (2) IV&V requirements tracing IR toolkit. Based on the methods developed in Phase I and their improvements developed in Phase II, we built a toolkit of IR methods for IV&V requirements tracing. The toolkit has been integrated, at the data level, with SAIC's SuperTracePlus (STP) tool; (3) Toolkit testing. We tested the methods included in the IV&V requirements tracing IR toolkit on a number of projects.

Simultaneous speciation and preconcentration of ultra traces of inorganic tellurium and selenium in environmental samples by hollow fiber liquid phase microextraction prior to electrothermal atomic absorption spectroscopy determination.

PubMed

Ghasemi, Ensieh; Najafi, Nahid Mashkouri; Raofie, Farhad; Ghassempour, Alireza

2010-09-15

A simple and effective speciation and preconcentration method based on hollow fiber liquid phase microextraction (HF-LPME) was developed for simultaneous separation of trace inorganic tellurium and selenium in environmental samples prior to electrothermal atomic absorption spectroscopy (ETAAS) determination. The method involves the selective extraction of the Te (IV) and Se (IV) species by HF-LPME with the use of ammonium pyrrolidinecarbodithioate (APDC) as the chelating agent. The complex compounds were extracted into 10 microL of toluene and the solutions were injected into a graphite furnace for the determination of Te (IV) and Se (IV). To determine the total tellurium and selenium in the samples, first Te (VI) and Se (VI) were reduced to Te (IV) and Se (IV), and then the microextraction method was performed. The experimental parameters of HF-LPME were optimized using a central composite design after a 2(n-1) fractional factorial experimental design. Under optimum conditions, enrichment factors of up to 520 and 480 were achieved for Te (IV) and Se (IV), respectively. The detection limits were 4 ng L(-1) with 3.5% RSD (n=5, c=2.0 microg L(-1)) for Te (IV) and 5 ng L(-1) with 3.1% RSD for Se (IV). The applicability of the developed technique was evaluated by application to spiked, environmental water and soil samples. Copyright 2010 Elsevier B.V. All rights reserved.

Spectroscopic characterization of zirconium(IV) and hafniumf(IV) gallate phthalocyanines in monolithic silica gels obtained by sol gel method

NASA Astrophysics Data System (ADS)

Gerasymchuk, Y. S.; Chernii, V. Ya.; Tomachynski, L. A.; Legendziewicz, J.; Radzki, St.

2005-07-01

The Zr(IV) and Hf(IV) phthalocyanines, with gallate as axial ligand coordinated to the central metal atom of phthalocyanine, were incorporated in silica gels during sol-gel process with using tetraethyl orthosilicate (TEOS) as precursor. The obtained mixed inorganic-organic composites were transparent and homogeneous. The absorption and emission properties of these materials in comparison with the spectra of the Zr(IV) and Hf(IV) phthalocyanines in various solvents were investigated. The spectra were correlated with various stage of the sol-gel process. It was established that in the gels concurrence of the monomer and dimer form is different in sol, alco-, hydro- and xerogels. The intensive 700-725 nm fluorescence emission upon relatively long-wavelength excitation and unusually large (about 45 nm) Stokes shift in the Q region, suggest that Zr(IV) and Hf(IV) phthalocyanines could be considered as photosensitizers in the PDT method (photodynamic therapy).

Data Combination and Instrumental Variables in Linear Models

ERIC Educational Resources Information Center

Khawand, Christopher

2012-01-01

Instrumental variables (IV) methods allow for consistent estimation of causal effects, but suffer from poor finite-sample properties and data availability constraints. IV estimates also tend to have relatively large standard errors, often inhibiting the interpretability of differences between IV and non-IV point estimates. Lastly, instrumental…

An iconic programming language for sensor-based robots

NASA Technical Reports Server (NTRS)

Gertz, Matthew; Stewart, David B.; Khosla, Pradeep K.

1993-01-01

In this paper we describe an iconic programming language called Onika for sensor-based robotic systems. Onika is both modular and reconfigurable and can be used with any system architecture and real-time operating system. Onika is also a multi-level programming environment wherein tasks are built by connecting a series of icons which, in turn, can be defined in terms of other icons at the lower levels. Expert users are also allowed to use control block form to define servo tasks. The icons in Onika are both shape and color coded, like the pieces of a jigsaw puzzle, thus providing a form of error control in the development of high level applications.

Historical and social aspects of halitosis.

PubMed

Elias, Marina Sá; Ferriani, Maria das Graças Carvalho

2006-01-01

Buccal odors have always been a factor of concern for society. This study aims to investigate the historical and social base of halitosis, through systematized research in the database BVS (biblioteca virtual em saúde - virtual library in health) and also in books. Lack of knowledge on how to prevent halitosis allows for its occurrence, limiting quality of life. As social relationships are one of the pillars of the quality of life concept, halitosis needs to be considered a factor of negative interference. Education in health should be accomplished with a view to a dynamic balance, involving human beings' physical and psychological aspects, as well as their social interactions, so that individuals do not become jigsaw puzzles of sick parts.

Can we improve C IV-based single epoch black hole mass estimations?

NASA Astrophysics Data System (ADS)

Mejía-Restrepo, J. E.; Trakhtenbrot, B.; Lira, P.; Netzer, H.

2018-05-01

In large optical surveys at high redshifts (z > 2), the C IV broad emission line is the most practical alternative to estimate the mass (MBH) of active super-massive black holes (SMBHs). However, mass determinations obtained with this line are known to be highly uncertain. In this work we use the Sloan Digital Sky Survey Data Release 7 and 12 quasar catalogues to statistically test three alternative methods put forward in the literature to improve C IV-based MBH estimations. These methods are constructed from correlations between the ratio of the C IV line-width to the low ionization line-widths (Hα, Hβ and Mg II) and several other properties of rest-frame UV emission lines. Our analysis suggests that these correction methods are of limited applicability, mostly because all of them depend on correlations that are driven by the linewidth of the C IV profile itself and not by an interconnection between the linewidth of the C IV line with the linewidth of the low ionization lines. Our results show that optical C IV-based mass estimates at high redshift cannot be a proper replacement for estimates based on IR spectroscopy of low ionization lines like Hα, Hβ and Mg II.

A unique dual recognition hairpin probe mediated fluorescence amplification method for sensitive detection of uracil-DNA glycosylase and endonuclease IV activities.

PubMed

Wu, Yushu; Yan, Ping; Xu, Xiaowen; Jiang, Wei

2016-03-07

Uracil-DNA glycosylase (UDG) and endonuclease IV (Endo IV) play cooperative roles in uracil base-excision repair (UBER) and inactivity of either will interrupt the UBER to cause disease. Detection of UDG and Endo IV activities is crucial to evaluate the UBER process in fundamental research and diagnostic application. Here, a unique dual recognition hairpin probe mediated fluorescence amplification method was developed for sensitively and selectively detecting UDG and Endo IV activities. For detecting UDG activity, the uracil base in the probe was excised by the target enzyme to generate an apurinic/apyrimidinic (AP) site, achieving the UDG recognition. Then, the AP site was cleaved by a tool enzyme Endo IV, releasing a primer to trigger rolling circle amplification (RCA) reaction. Finally, the RCA reaction produced numerous repeated G-quadruplex sequences, which interacted with N-methyl-mesoporphyrin IX to generate an enhanced fluorescence signal. Alternatively, for detecting Endo IV activity, the uracil base in the probe was first converted into an AP site by a tool enzyme UDG. Next, the AP site was cleaved by the target enzyme, achieving the Endo IV recognition. The signal was then generated and amplified in the same way as those in the UDG activity assay. The detection limits were as low as 0.00017 U mL(-1) for UDG and 0.11 U mL(-1) for Endo IV, respectively. Moreover, UDG and Endo IV can be well distinguished from their analogs. This method is beneficial for properly evaluating the UBER process in function studies and disease prognoses.

Growth performance and pork fat quality as measured by three methods of pigs fed 20% DDGS and slaughtered using a standard industry split marketing strategy.

PubMed

Shircliff, K E; Callahan, Z D; Wilmoth, T A; Ohman, C E; Johnson, R C; Wiegand, B R

2015-10-01

A total of 40 pens containing 22 crossbred barrows (initial BW = 43.07 ± 1.61 kg; PIC 1050 × PIC 337 genetics) were housed in a commercial wean to finish facility. Pens were randomly allotted to dietary treatments in a 2 × 3 factorial arrangement with 2 levels of dried distillers grains with solubles (DDGS; 0% or 20%) and chosen for 1 of 3 marketing cuts removing 4, 8, and 10 animals from each pen. Fat tissue samples were removed from the anterior tip of the jowl and posterior to the sternum on the belly edge 1d postmortem. Fatty acid composition was determined via the Folch method, and iodine values (IV) were calculated from chemical titrations, fatty acid profile (GC IV), and in-plant Bruker near-infrared (NIR) spectroscopy. Pearson's correlation coefficients for IV determination methods were estimated. Inclusion of 20% DDGS did not change ( > 0.05) growth performance, whereas marketing cut affected performance, with the second cut producing the most efficient pigs ( < 0.01). Total SFA and MUFA concentrations were higher ( < 0.01) in belly and jowl fat from pigs fed 0% DDGS. Total PUFA and the PUFA:SFA in belly and jowl fat was higher ( < 0.01) when 20% DDGS was fed. Dried distillers grains with solubles inclusion increased IV in belly and jowl as determined by all 3 methods. Regardless of dietary treatment or fat depot, Pearson correlation coefficients between titration and GC IV, titration and NIR, and GC IV and NIR were 0.46 ( < 0.01), 0.68 ( < 0.01), and 0.43 ( < 0.01), respectively. These correlations suggest methods may rank samples equally but do not provide the same absolute IV. Belly fat had a lower IV ( < 0.01) than jowl fat using titration or GC IV methods, suggesting pigs have varied degrees of physiological maturity at specific fat depots when weight end points are used during the finishing phase. In conclusion, feeding 20% DDGS negatively affected fat quality but not growth performance, and marketing time changed growth performance.

Criterion validity and clinical usefulness of Attention Deficit Hyperactivity Disorder Rating Scale IV in attention deficit hyperactivity disorder (ADHD) as a function of method and age.

PubMed

López-Villalobos, José A; Andrés-De Llano, Jesús; López-Sánchez, María V; Rodríguez-Molinero, Luis; Garrido-Redondo, Mercedes; Sacristán-Martín, Ana M; Martínez-Rivera, María T; Alberola-López, Susana

2017-02-01

The aim of this research is to analyze Attention Deficit Hyperactivity Disorder Rating Scales IV (ADHD RS-IV) criteria validity and its clinical usefulness for the assessment of Attention Deficit Hyperactivity Disorder (ADHD) as a function of assessment method and age. A sample was obtained from an epidemiological study (n = 1095, 6-16 years). Clinical cases of ADHD  (ADHD-CL) were selected by dimensional ADHD RS-IV and later by clinical interview (DSM-IV). ADHD-CL cases were compared with four categorical results of ADHD RS-IV provided by parents (CATPA), teachers (CATPR), either parents or teachers (CATPAOPR) and both parents and teachers (CATPA&PR). Criterion validity and clinical usefulness of the answer modalities to ADHD RS-IV were studied. ADHD-CL rate was 6.9% in childhood, 6.2% in preadolescence and 6.9% in adolescence. Alternative methods to the clinical interview led to increased numbers of ADHD cases in all age groups analyzed, in the following sequence: CATPAOPR> CATPRO> CATPA> CATPA&PR> ADHD-CL. CATPA&PR was the procedure with the greatest validity, specificity and clinical usefulness in all three age groups, particularly in the childhood. Isolated use of ADHD RS-IV leads to an increase in ADHD cases compared to clinical interview, and varies depending on the procedure used.

Development of an ESL curriculum to educate Chinese immigrants about hepatitis B.

PubMed

Taylor, Victoria M; Coronado, Gloria; Acorda, Elizabeth; Teh, Chong; Tu, Shin-Ping; Yasui, Yutaka; Bastani, Roshan; Hislop, T Gregory

2008-08-01

Chinese immigrants to North America have substantially higher rates of chronic hepatitis B infection than the general population. One area for strategic development in the field of health education is the design and evaluation of English-as-a-Second language (ESL) curricula. The theoretical perspective of the Health Behavior Framework, results from a community-based survey of Chinese Canadian immigrants with limited English proficiency, and findings from focus groups of ESL instructors as well as Chinese ESL students were used to develop a hepatitis B ESL educational module. This research was conducted in Vancouver, BC. Survey data showed that less than three-fifths of the respondents had been tested for hepatitis B, and documented some important hepatitis B knowledge deficits. Further, only about one-quarter had ever received a physician recommendation for hepatitis B serologic testing. The ESL curriculum aims to both promote hepatitis B testing and improve knowledge, and includes seven different ESL exercises: Warm-up, vocabulary cards, information-gap, video, jigsaw, guided discussion, and problem/advice cards. Our quantitative and qualitative methods for curriculum development could be replicated for other health education topics and in other limited English speaking populations.

Sparticles in motion: Analyzing compressed SUSY scenarios with a new method of event reconstruction

NASA Astrophysics Data System (ADS)

Jackson, Paul; Rogan, Christopher; Santoni, Marco

2017-02-01

The observation of light superpartners from a supersymmetric extension to the Standard Model is an intensely sought-after experimental outcome, providing an explanation for the stabilization of the electroweak scale and indicating the existence of new particles which could be consistent with dark matter phenomenology. For compressed scenarios, where sparticle spectra mass splittings are small and decay products carry low momenta, dedicated techniques are required in all searches for supersymmetry. In this paper we suggest an approach for these analyses based on the concept of recursive jigsaw reconstruction, decomposing each event into a basis of complementary observables, for cases where strong initial state radiation has sufficient transverse momentum to elicit the recoil of any final state sparticles. We introduce a collection of kinematic observables which can be used to probe compressed scenarios, in particular exploiting the correlation between missing momentum and that of radiative jets. As an example, we study squark and gluino production, focusing on mass-splittings between parent superparticles and their lightest decay products between 25 and 200 GeV, in hadronic final states where there is an ambiguity in the provenance of reconstructed jets.

Titrimetric and Spectrophotometric Methods for the Assay of Ketotifen Using Cerium(IV) and Two Reagents

PubMed Central

Raghu, Madihalli Srinivas; Basavaiah, Kanakapura; Prashanth, Kudige Nagaraj; Vinay, Kanakapura Basavaiah

2013-01-01

One titrimetric and two spectrophotometric methods are described for the determination of ketotifen fumarate (KTF) in bulk drug and in tablets using cerium(IV) as the oxidimetric agent. In titrimetry (method A), the drug was treated with a measured excess of cerium(IV) in H2SO4 medium and after a standing time of 10 min, the surplus oxidant was determined by back titration with iron(II). The spectrophotometric procedures involve addition of a known excess of cerium(IV) to KTF in acid medium followed by the determination of unreacted oxidant by reacting with either p-dimethyl amino benzaldehyde and measuring the resulting colour at 460 nm (method B) or o-dianisidine and subsequent measurement of the absorbance of coloured product at 470 nm (method C). Titrimetric assay is based on a 1 : 2 reaction stoichiometry between KTF and cerium(IV) and the method is applicable over 2–18 mg range. In spectrophotometry, regression analysis of Beer's law plots showed a good correlation in 0.4–8.0 and 0.4–10.0 g mL−1 KTF ranges for method B and method C, respectively, and the corresponding molar absorptivity coefficients are calculated to be 4.0 × 104 and 3.7 × 104 L mol−1 cm−1. PMID:24324496

New spectrofluorimetric and spectrophotometric methods for the determination of the analgesic drug, nalbuphine in pharmaceutical and biological fluids.

PubMed

El-Didamony, Akram M; Ali, Ismail I

2013-01-01

We describe the first studies of a simple and sensitive spectrofluorimetric and spectrophotometric methods for the analysis of nalbuphine (NLB) in dosage form and biological fluids. The spectrofluorimetric method was based on the oxidation of NLB with Ce(IV) to produce Ce(III) and its fluorescence was monitored at 352 nm after excitation at 250 nm. The spectrophotometric method involves addition of a known excess of Ce(IV) to NLB in acid medium, followed by determination of residual Ce(IV) by reacting with a fixed amount of methyl orange and measuring absorbance at 510 nm. In both methods, the amount of Ce(IV) reacted corresponds to the amount of NLB and measured fluorescence or absorbance were found to increase linearly with the concentration of NLB, which are corroborated by correlation coefficients of 0.9997 and 0.9999 for spectrofluorimetric and spectrophotometric methods, respectively. Different variables affecting the reaction conditions such as concentrations of Ce(IV), type and concentration of acid medium, reaction time, temperature, and diluting solvents were carefully studied and optimized. The accuracy and precision of the methods were evaluated on intra-day and inter-day basis. The proposed methods were successfully applied for the determination of NLB in pharmaceutical formulation and biological samples with good recoveries. Copyright © 2012 John Wiley & Sons, Ltd.

[Evaluation of volatile organic compounds (VOCs) emitted from household products by small chamber test method].

PubMed

Tanaka-Kagawa, Toshiko; Jinno, Hideto; Obama, Tomoko; Miyagawa, Makoto; Yoshikawa, Jun; Komatsu, Kazuhiro; Tokunaga, Hiroshi

2007-01-01

Identification and removal/replacement of sources of indoor air pollutants, such as volatile organic compounds (VOCs) and aldehydes, are most effective measures to reduce indoor chemical exposures. For instance, formaldehyde emissions from building materials have been successfully decreased by the restrictions on interior finishing materials under the amended Building Standard Low in Japan. This study was performed to estimate quantitatively influence of household products on indoor air quality. VOC emissions were investigated for 51 products including interior materials, bedclothes, stationeries, toys and printed matters by the small chamber test method (JIS A 1901) under the standard conditions of 28 degrees C, 50% relative humidity and 0.5 times/h ventilation. Total VOC (TVOC) emissions from the tablecloth and gloves, both of which were made of polyvinyl chloride, showed the highest emission rates; over 2000 microg/(m2 x h) after 1 day, and then rapidly decreased to less than 500 microg/(m2 x h) in a week. Among stationeries/toys for schoolchildren and infants, jigsaw puzzle and play mat exhibited higher TVOC emission rates (38 and 24 microg/(m2 x h) after 1 day, respectively). As for VOCs emitted from printed matters, high boiling-point compounds (higher than that of n-tridecane) were typically identified along with toluene, xylenes and ethylbenzene. These results revealed that VOC emissions from household products may influence significantly indoor air quality.

Thermoregulation and stress hormone recovery after exercise dehydration: comparison of rehydration methods.

PubMed

McDermott, Brendon P; Casa, Douglas J; Lee, Elaine; Yamamoto, Linda; Beasley, Kathleen; Emmanuel, Holly; Anderson, Jeffrey; Pescatello, Linda; Armstrong, Lawrence E; Maresh, Carl

2013-01-01

Athletic trainers recommend and use a multitude of rehydration (REHY) methods with their patients. The REHY modality that most effectively facilitates recovery is unknown. To compare 5 common REHY methods for thermoregulatory and stress hormone recovery after exercise dehydration (EXDE) in trained participants. Randomized, cross-over, controlled study. Twelve physically active, non-heat-acclimatized men (age = 23 ± 4 years, height = 180 ± 6 cm, mass = 81.3 ± 3.7 kg, VO2max = 56.9 ± 4.4 mL·min(-1)·kg(-1), body fat = 7.9% ± 3%) participated. Participants completed 20-hour fluid restriction and 2-hour EXDE; they then received no fluid (NF) or REHY (half-normal saline) via ad libitum (AL), oral (OR), intravenous (IV), or combination IV and OR (IV + OR) routes for 30 minutes; and then were observed for another 30 minutes. Body mass, rectal temperature, 4-site mean weighted skin temperature, plasma stress hormone concentrations, and environmental symptoms questionnaire (ESQ) score. Participants were hypohydrated (body mass -4.23% ± 0.22%) post-EXDE. Rectal temperature for the NF group was significantly greater than for the IV group (P = .023) at 30 minutes after beginning REHY (REHY30) and greater than OR, IV, and IV + OR (P ≤ .009) but not AL (P = .068) at REHY60. Mean weighted skin temperature during AL was less than during IV + OR at REHY5 (P = .019). The AL participants demonstrated increased plasma cortisol concentrations compared with IV + OR, independent of time (P = .015). No differences existed between catecholamine concentrations across treatments (P > .05). The ESQ score was increased at REHY60 for NF, AL, OR, and IV (P < .05) but not for IV + OR (P = .217). The NF ESQ score was greater than that of IV + OR at REHY60 (P = .012). Combination IV + OR REHY reduced body temperature to a greater degree than OR and AL REHY when compared with NF. Future studies addressing clinical implications are needed.

Student perception of group dynamics predicts individual performance: Comfort and equity matter

PubMed Central

Theobald, Elli J.; Eddy, Sarah L.; Grunspan, Daniel Z.; Wiggins, Benjamin L.

2017-01-01

Active learning in college classes and participation in the workforce frequently hinge on small group work. However, group dynamics vary, ranging from equitable collaboration to dysfunctional groups dominated by one individual. To explore how group dynamics impact student learning, we asked students in a large-enrollment university biology class to self-report their experience during in-class group work. Specifically, we asked students whether there was a friend in their group, whether they were comfortable in their group, and whether someone dominated their group. Surveys were administered after students participated in two different types of intentionally constructed group activities: 1) a loosely-structured activity wherein students worked together for an entire class period (termed the ‘single-group’ activity), or 2) a highly-structured ‘jigsaw’ activity wherein students first independently mastered different subtopics, then formed new groups to peer-teach their respective subtopics. We measured content mastery by the change in score on identical pre-/post-tests. We then investigated whether activity type or student demographics predicted the likelihood of reporting working with a dominator, being comfortable in their group, or working with a friend. We found that students who more strongly agreed that they worked with a dominator were 17.8% less likely to answer an additional question correct on the 8-question post-test. Similarly, when students were comfortable in their group, content mastery increased by 27.5%. Working with a friend was the single biggest predictor of student comfort, although working with a friend did not impact performance. Finally, we found that students were 67% less likely to agree that someone dominated their group during the jigsaw activities than during the single group activities. We conclude that group activities that rely on positive interdependence, and include turn-taking and have explicit prompts for students to explain their reasoning, such as our jigsaw, can help reduce the negative impact of inequitable groups. PMID:28727749

Synthesis and Characterization of Tin(IV) Oxide Obtained by Chemical Vapor Deposition Method

NASA Astrophysics Data System (ADS)

Nagirnyak, Svitlana V.; Lutz, Victoriya A.; Dontsova, Tatiana A.; Astrelin, Igor M.

2016-07-01

The effect of precursors on the characteristics of tin oxide obtained by chemical vapor deposition (CVD) method was investigated. The synthesis of nanosized tin(IV) oxide was carried out with the use of two different precursors: tin(II) oxalate obtained using tin chloride(II) and oxalic acid; tin(II) oxalate obtained using tin chloride(II); and ammonium oxalate. The synthesized tin(IV) oxide samples were studied by electron microscopy, X-ray diffraction and optical spectra. The lattice parameters of tin(IV) oxide samples were defined, the bandgap of samples were calculated.

Preconcentration and speciation of ultra-trace Se (IV) and Se (VI) in environmental water samples with nano-sized TiO2 colloid and determination by HG-AFS.

PubMed

Fu, Jiaqi; Zhang, Xu; Qian, Shahua; Zhang, Lin

2012-05-30

A united method for speciation analysis of Se (IV) and Se (VI) in environmental water samples was developed using nano-sized TiO(2) colloid as adsorbent and hydride generation atomic fluorescence spectrometry (HG-AFS) as determination means. When the pH values of bulk solution were between 6.0 and 7.0, successful adsorption onto 1 mL nano-sized TiO(2) colloid (0.2%) was achieved for more than 97.0% of Se (IV) while Se (VI) barely got adsorbed. Therefore, the method made it possible to preconcentrate and determine Se (IV) and Se (VI) separately. The precipitated TiO(2) with concentrated selenium was directly converted to colloid without desorption. Selenium in the resulting colloid was then determined by HG-AFS. The detection limits (3σ) and relative standard deviations (R.S.D) of this method were 24 ng/L and 42 ng/L, 7.8% (n=6) and 7.0% (n=6) for Se (IV) and Se (VI), respectively. This simple, sensitive, and united method was successfully applied to the separation and speciation of ultra-trace Se (IV) and Se (VI) in environmental water samples. Copyright © 2012 Elsevier B.V. All rights reserved.

Methods for synthesis of semiconductor nanocrystals and thermoelectric compositions

DOEpatents

Ren, Zhifeng [Newton, MA; Chen, Gang [Carlisle, MA; Poudel, Bed [Watertown, MA; Kumar, Shankar [Watertown, MA; Wang, Wenzhong [Newton, MA; Dresselhaus, Mildred [Arlington, MA

2007-08-14

The present invention provides methods for synthesis of IV VI nanostructures, and thermoelectric compositions formed of such structures. In one aspect, the method includes forming a solution of a Group IV reagent, a Group VI reagent and a surfactant. A reducing agent can be added to the solution, and the resultant solution can be maintained at an elevated temperature, e.g., in a range of about 20.degree. C. to about 360.degree. C., for a duration sufficient for generating nanoparticles as binary alloys of the IV VI elements.

Methods for synthesis of semiconductor nanocrystals and thermoelectric compositions

NASA Technical Reports Server (NTRS)

Chen, Gang (Inventor); Poudel, Bed (Inventor); Kumar, Shankar (Inventor); Dresselhaus, Mildred (Inventor); Ren, Zhifeng (Inventor); Wang, Wenzhong (Inventor)

2007-01-01

The present invention provides methods for synthesis of IV VI nanostructures, and thermoelectric compositions formed of such structures. In one aspect, the method includes forming a solution of a Group IV reagent, a Group VI reagent and a surfactant. A reducing agent can be added to the solution, and the resultant solution can be maintained at an elevated temperature, e.g., in a range of about 20.degree. C. to about 360.degree. C., for a duration sufficient for generating nanoparticles as binary alloys of the IV VI elements.

Instrumental variables and Mendelian randomization with invalid instruments

NASA Astrophysics Data System (ADS)

Kang, Hyunseung

Instrumental variables (IV) methods have been widely used to determine the causal effect of a treatment, exposure, policy, or an intervention on an outcome of interest. The IV method relies on having a valid instrument, a variable that is (A1) associated with the exposure, (A2) has no direct effect on the outcome, and (A3) is unrelated to the unmeasured confounders associated with the exposure and the outcome. However, in practice, finding a valid instrument, especially those that satisfy (A2) and (A3), can be challenging. For example, in Mendelian randomization studies where genetic markers are used as instruments, complete knowledge about instruments' validity is equivalent to complete knowledge about the involved genes' functions. The dissertation explores the theory, methods, and application of IV methods when invalid instruments are present. First, when we have multiple candidate instruments, we establish a theoretical bound whereby causal effects are only identified as long as less than 50% of instruments are invalid, without knowing which of the instruments are invalid. We also propose a fast penalized method, called sisVIVE, to estimate the causal effect. We find that sisVIVE outperforms traditional IV methods when invalid instruments are present both in simulation studies as well as in real data analysis. Second, we propose a robust confidence interval under the multiple invalid IV setting. This work is an extension of our work on sisVIVE. However, unlike sisVIVE which is robust to violations of (A2) and (A3), our confidence interval procedure provides honest coverage even if all three assumptions, (A1)-(A3), are violated. Third, we study the single IV setting where the one IV we have may actually be invalid. We propose a nonparametric IV estimation method based on full matching, a technique popular in causal inference for observational data, that leverages observed covariates to make the instrument more valid. We propose an estimator along with inferential results that are robust to mis-specifications of the covariate-outcome model. We also provide a sensitivity analysis should the instrument turn out to be invalid, specifically violate (A3). Fourth, in application work, we study the causal effect of malaria on stunting among children in Ghana. Previous studies on the effect of malaria and stunting were observational and contained various unobserved confounders, most notably nutritional deficiencies. To infer causality, we use the sickle cell genotype, a trait that confers some protection against malaria and was randomly assigned at birth, as an IV and apply our nonparametric IV method. We find that the risk of stunting increases by 0.22 (95% CI: 0.044,1) for every malaria episode and is sensitive to unmeasured confounders.

Effect of method of crystallization on the IV-III and IV-II polymorphic transitions of ammonium nitrate.

PubMed

Vargeese, Anuj A; Joshi, Satyawati S; Krishnamurthy, V N

2009-01-15

A study has been undertaken on the effect of crystallization method on the IV<-->III transition of ammonium nitrate (AN). AN is crystallized in three different ways, viz. recrystallization, evaporative crystallization and melt crystallization. When the samples were crystallized from saturated aqueous solution, ideal crystals were formed, which behaved differently from the crystals formed from the other methods. The DTA examination of the crystals showed that the crystals have different transition behaviour. The moisture uptake of the samples determined were found to have influenced by the mode of crystallization. The samples were further analyzed by powder X-ray diffraction (XRD) and scanning electron microscopy (SEM). The present study showed that the parameters like thermal history, number of previous transformations and moisture content have a very negligible influence on the IV<-->III transition of AN as compared to the method of crystallization.

Method for photochemical reduction of uranyl nitrate by tri-N-butyl phosphate and application of this method to nuclear fuel reprocessing

DOEpatents

De Poorter, Gerald L.; Rofer-De Poorter, Cheryl K.

1978-01-01

Uranyl ion in solution in tri-n-butyl phosphate is readily photochemically reduced to U(IV). The product U(IV) may effectively be used in the Purex process for treating spent nuclear fuels to reduce Pu(IV) to Pu(III). The Pu(III) is readily separated from uranium in solution in the tri-n-butyl phosphate by an aqueous strip.

Graphene oxide-TiO2 composite solid phase extraction combined with graphite furnace atomic absorption spectrometry for the speciation of inorganic selenium in water samples.

PubMed

Zhang, Yanan; Chen, Beibei; Wu, Shaowei; He, Man; Hu, Bin

2016-07-01

In this paper, a method of graphene oxide (GO)-TiO2 composite solid phase extraction followed by graphite furnace atomic absorption spectrometry (GFAAS) detection was proposed for the speciation of inorganic selenium in environmental waters. The adsorption behavior of inorganic Se(IV) and Se(VI) on the GO-TiO2(1:1) composite was investigated. It was found that Se(IV) was quantitatively retained on the GO-TiO2 composites within a wide pH range of 0.5-10, while Se(VI) was quantitatively adsorbed on GO-TiO2(1:1) composite at pH 0.5-2, and no obvious adsorption of Se(VI) within the pH range of 4-10 was found. By selecting pH 6.0, Se(IV) could be easily determined. After reduction of Se(VI), total Se was determined by the proposed method, and Se(VI) was calculated as the difference between the total Se and Se(IV). The factors affecting the separation/preconcentration of Se(IV) and Se(VI) were studied. Under the optimum conditions, the isothermal adsorption of Se(IV) on the GO-TiO2(1:1) composite fitted Langmuir model; a linear range over 0.1-12ngmL(-1) was obtained. The limit of detection (LOD) and precision of the method for Se(IV) was 0.04ngmL(-1) and 9.4% (cSe(IV)=0.5ngmL(-1), n=7), respectively. In order to verify the accuracy of the method, a standard water sample (GSBZ50031-94) was analyzed, and the determined value was in a good agreement to the certified value. The established method was applied to inorganic Se speciation in environmental water samples and the recovery of 87.4-102% was obtained for the spiked samples. Copyright © 2016 Elsevier B.V. All rights reserved.

Exporting simulation technology to the Philippines: a comparative study of traditional versus simulation methods for teaching intravenous cannulation.

PubMed

Sotto, Juan Alejandro R; Ayuste, Eduardo C; Bowyer, Mark W; Almonte, Josefina R; Dofitas, Rodney B; Lapitan, Marie C M; Pimentel, Elisabeth A; Ritter, E Matthew; Wherry, David C

2009-01-01

This study examines effectiveness of a donated Laerdal Virtual I.V. simulator when compared with traditional methods of teaching intravenous (IV) cannulation to third year medical students in the Philippines. Forty novice Filipino medical students viewed an instructional video on how to start intravenous lines and were then randomly divided into two groups of twenty. The "Traditional" group observed an IV insertion on an actual patient performed by an experienced practitioner, and then subsequently performed an IV on an actual patient which was videotaped. The "Simulation" group practiced the Virtual I.V. simulator until they successfully completed level three using the "doctor" setting. These students then performed an IV on an actual patient which was videotaped. The videotapes for both groups were reviewed by two pre-trained (Inter-rater reliability of > or =0.84) observers who were blinded to the group using a previously validated checklist for IV insertion. Students trained on the Virtual I.V. showed significantly greater success in successfully starting an IV on an actual patient (40% VS. 15%, p<0.05), decreased constrictive band time (p<.05), increased raw score on the check list (p<.03), and decreased overall time to start an IV (p<.05). The technology was well received but wider application in the non western world is limited by lack of in country company support and the relative expense.

METHOD OF RECOVERING TRANSURANIC ELEMENTS OF AN ATOMIC NUMBER BELOW 95

DOEpatents

Seaborg, G.T.; James, R.A.

1959-12-15

The concentration of neptanium or plutonium by two carrier precipitation steps with identical carriers but using (after dissolution of the first carrier in nitric acid) a reduced quantity of carrier for the second precipitation is discussed. Carriers suitable are uranium(IV) hypophosphate, uranium(IV) pyrophosphate, uranium(IV) oxalate, thorium oxalate, thorium citrate, thorium tartrate, thorium sulfide, and uranium(IV) sulfide.

Digital Images on the DIME

NASA Technical Reports Server (NTRS)

2003-01-01

With NASA on its side, Positive Systems, Inc., of Whitefish, Montana, is veering away from the industry standards defined for producing and processing remotely sensed images. A top developer of imaging products for geographic information system (GIS) and computer-aided design (CAD) applications, Positive Systems is bucking traditional imaging concepts with a cost-effective and time-saving software tool called Digital Images Made Easy (DIME(trademark)). Like piecing a jigsaw puzzle together, DIME can integrate a series of raw aerial or satellite snapshots into a single, seamless panoramic image, known as a 'mosaic.' The 'mosaicked' images serve as useful backdrops to GIS maps - which typically consist of line drawings called 'vectors' - by allowing users to view a multidimensional map that provides substantially more geographic information.

Rapid Intravenous Rehydration Therapy in Children With Acute Gastroenteritis: A Systematic Review.

PubMed

Toaimah, Fatihi Hassan Soliman; Mohammad, Hala Mohammad Fathi

2016-02-01

Rapid intravenous (IV) rehydration is commonly used for the management of pediatric gastroenteritis in the emergency department. The current practice shows wide variation in the volume and rate of rapid IV hydration. The aim of this review was to assess the efficacy of rapid IV rehydration compared with standard method in children with gastroenteritis. MEDLINE (1946-2014), EMBASE (1974-2014), and CENTRAL via the Cochrane Library (Issue 8, 2014) were systematically searched to identify eligible studies. Inclusion criteria were randomized controlled trials of rapid IV rehydration in children with gastroenteritis. A total of 1513 articles were retrieved, and our inclusion criteria were met by 3 studies, with a total of 464 participants. The percentage of children who were successfully rehydrated and tolerated oral fluids at 2 to 4 hours after starting IV fluid therapy ranged from 69% to 100% in both rapid IV rehydration and standard method. Time to discharge ranged from 2 to 6 hours (rapid rehydration) versus 2 to 5 hours (standard rehydration). Emergency department revisits ranged from 3% to 16% (rapid rehydration) versus 5% to 14% (standard). Summarized results suggested that rapid IV rehydration may be associated with longer time-to-discharge and higher readmission rates. The new evidence fails to demonstrate superiority of large-volume (60 mL/kg/h) over standard (20 mL/kg/h) IV rehydration. Standard volume IV rehydration for 1 to 4 hours followed by oral hydration or maintenance IV fluids seems sufficient for most children with gastroenteritis requiring IV fluid administration. However, more evidence is needed to establish an optimal IV rehydration regimen.

Extractive Spectrophotometric Determination of Nortriptyline Hydrochloride Using Sudan II, IV and Black B.

PubMed

Amin, A S; Saleh, H M

2017-08-17

A simple spectrophotometric methods has been developed for the determination of nortriptyline hydrochloride in pure and in pharmaceuticalformulations based on the formation of ion-pair complexes with sudun II (S II ), sudan (IV) (S IV ) and sudan black B (S BB ). The selectivity of the method was improved through extraction with chloroform. The optimum conditions for complete extracted colour development were assessed. The absorbance measurements were made at 534, 596 and 649 nm for S II , S IV and S BB complexes, respectively. The calibration graph was linear in the ranges 0.5- 280. 0.5- 37.5 and 0.5 - 31.0 μg ml -1 of the drug usiny the same reagents, respectively. The precision of the procedure was checked by calculating the relative standard deviation of ten replicate determinations on 15 μg ml -1 of nortriptyline HCI and was found to be 1.7, 1.3 and 1.55% using S II , S IV , and S BB complexes, respectively. The molar absorptivity and Sandell sensitivity for each ion-pair were calculated. The proposed methods were successfully applied to the deterniination of pure nortriptyline HCI and in pharmaceutical formulations, and the results demonstrated that the method is equally accurate, precise and reproducible as the official method.

Comparison of LSS-IV and LISS-III+LISS-IV merged data for classification of crops

NASA Astrophysics Data System (ADS)

Hebbar, R.; Sesha Sai, M. V. R.

2014-11-01

Resourcesat-1 satellite with its unique capability of simultaneous acquisition of multispectral images at different spatial resolutions (AWiFS, LISS-III and LISS-IV MX / Mono) has immense potential for crop inventory. The present study was carried for selection of suitable LISS-IV MX band for data fusion and its evaluation for delineation different crops in a multi-cropped area. Image fusion techniques namely intensity hue saturation (IHS), principal component analysis (PCA), brovey, high pass filter (HPF) and wavelet methods were used for merging LISS-III and LISS-IV Mono data. The merged products were evaluated visually and through universal image quality index, ERGAS and classification accuracy. The study revealed that red band of LISS-IV MX data was found to be optimal band for merging with LISS-III data in terms of maintaining both spectral and spatial information and thus, closely matching with multispectral LISS-IVMX data. Among the five data fusion techniques, wavelet method was found to be superior in retaining image quality and higher classification accuracy compared to commonly used methods of IHS, PCA and Brovey. The study indicated that LISS-IV data in mono mode with wider swath of 70 km could be exploited in place of 24km LISS-IVMX data by selection of appropriate fusion techniques by acquiring monochromatic data in the red band.

Extraction behaviour and mechanism of Pt(iv) and Pd(ii) by liquid-liquid extraction with an ionic liquid [HBBIm]Br.

PubMed

Liu, Wenhui; Wang, Qi; Zheng, Yan; Wang, Shubin; Yan, Yan; Yang, Yanzhao

2017-06-06

In this study, a method of one-step separation and recycling of high purity Pd(ii) and Pt(iv) using an ionic liquid, 1-butyl-3-benzimidazolium bromate ([HBBIm]Br), was investigated. The effects of [HBBIm]Br concentration, initial metal concentration, and loading capacity of [HBBIm]Br were examined in detail. It was observed that [HBBIm]Br was a very effective extractant for selectively extracting Pd(ii) and precipitating Pt(iv). Through selectively extracting Pd(ii) and precipitating Pt(iv), each metal with high purity was separately obtained from mixed Pd(ii) and Pt(iv) multi-metal solution. The method of one-step separation of Pd(ii) and Pt(iv) is simple and convenient. The anion exchange mechanism between [HBBIm]Br and Pt(iv) was proven through Job's method and FTIR and 1 H NMR spectroscopies. The coordination mechanism between [HBBIm]Br and Pd(ii) was demonstrated via single X-ray diffraction and was found to be robust and distinct, as supported by the ab initio quantum-chemical studies. The crystals of the [PdBr 2 ·2BBIm] complex were formed first. Moreover, the influence of the concentrations of hydrochloric acid, sodium chloride, and sodium nitrate on the precipitation of Pt(iv) and extraction of Pd(ii) was studied herein. It was found that only the concentration of H + could inhibit the separation of Pt(iv) because H + could attract the anion PtCl 6 2- ; thus, the exchange (anion exchange mechanism) between the anions PtCl 6 2- and Br - was prevented. However, both the concentration of H + and Cl - can obviously inhibit the extraction of Pd(ii) because H + and Cl - are the reaction products and increasing their concentration can inhibit the progress of the reaction (coordination mechanism).

WAIS-IV and WISC-IV Structural Validity: Alternate Methods, Alternate Results. Commentary on Weiss et al. (2013a) and Weiss et al. (2013b)

ERIC Educational Resources Information Center

Canivez, Gary L.; Kush, Joseph C.

2013-01-01

Weiss, Keith, Zhu, and Chen (2013a) and Weiss, Keith, Zhu, and Chen (2013b), this issue, report examinations of the factor structure of the Wechsler Adult Intelligence Scale-Fourth Edition (WAIS-IV) and Wechsler Intelligence Scale for Children-Fourth Edition (WISC-IV), respectively; comparing Wechsler Hierarchical Model (W-HM) and…

Thermoregulation and Stress Hormone Recovery After Exercise Dehydration: Comparison of Rehydration Methods

PubMed Central

McDermott, Brendon P.; Casa, Douglas J.; Lee, Elaine; Yamamoto, Linda; Beasley, Kathleen; Emmanuel, Holly; Anderson, Jeffrey; Pescatello, Linda; Armstrong, Lawrence E.; Maresh, Carl

2013-01-01

Context: Athletic trainers recommend and use a multitude of rehydration (REHY) methods with their patients. The REHY modality that most effectively facilitates recovery is unknown. Objective: To compare 5 common REHY methods for thermoregulatory and stress hormone recovery after exercise dehydration (EXDE) in trained participants. Design: Randomized, cross-over, controlled study. Patients or Other Participants: Twelve physically active, non–heat-acclimatized men (age = 23 ± 4 years, height = 180 ± 6 cm, mass = 81.3 ± 3.7 kg, V̇o2max = 56.9 ± 4.4 mL·min−1·kg−1, body fat = 7.9% ± 3%) participated. Intervention(s): Participants completed 20-hour fluid restriction and 2-hour EXDE; they then received no fluid (NF) or REHY (half-normal saline) via ad libitum (AL), oral (OR), intravenous (IV), or combination IV and OR (IV + OR) routes for 30 minutes; and then were observed for another 30 minutes. Main Outcome Measure(s): Body mass, rectal temperature, 4-site mean weighted skin temperature, plasma stress hormone concentrations, and environmental symptoms questionnaire (ESQ) score. Results: Participants were hypohydrated (body mass −4.23% ± 0.22%) post-EXDE. Rectal temperature for the NF group was significantly greater than for the IV group (P = .023) at 30 minutes after beginning REHY (REHY30) and greater than OR, IV, and IV + OR (P ≤ .009) but not AL (P = .068) at REHY60. Mean weighted skin temperature during AL was less than during IV + OR at REHY5 (P = .019). The AL participants demonstrated increased plasma cortisol concentrations compared with IV + OR, independent of time (P = .015). No differences existed between catecholamine concentrations across treatments (P > .05). The ESQ score was increased at REHY60 for NF, AL, OR, and IV (P < .05) but not for IV + OR (P = .217). The NF ESQ score was greater than that of IV + OR at REHY60 (P = .012). Conclusions: Combination IV + OR REHY reduced body temperature to a greater degree than OR and AL REHY when compared with NF. Future studies addressing clinical implications are needed. PMID:24143900

Ovine progressive pneumonia virus is transmitted more effectively via aerosol nebulization than oral administration

USDA-ARS?s Scientific Manuscript database

A new method of experimental infection of ovine progressive pneumonia virus (OPPV), aerosol nebulization (Nb), was compared to intravenous (IV) and oral (PO) methods of experimental infection. Seven month old lambs were given 3.5 × 107 TCID50 of Dubois OPPV LMH19 isolate using IV, PO, or Nb methods ...

Self-report assessment of the DSM-IV personality disorders. Measurement of trait and distress characteristics: the ADP-IV.

PubMed

Schotte, C K; de Doncker, D; Vankerckhoven, C; Vertommen, H; Cosyns, P

1998-09-01

Self-report instruments assessing the DSM personality disorders are characterized by overdiagnosis due to their emphasis on the measurement of personality traits rather than the impairment and distress associated with the criteria. The ADP-IV, a Dutch questionnaire, introduces an alternative assessment method: each test item assesses 'Trait' as well as 'Distress/impairment' characteristics of a DSM-IV criterion. This item format allows dimensional as well as categorical diagnostic evaluations. The present study explores the validity of the ADP-IV in a sample of 659 subjects of the Flemish population. The dimensional personality disorder subscales, measuring Trait characteristics, are internally consistent and display a good concurrent validity with the Wisconsin Personality Disorders Inventory. Factor analysis at the item-level resulted in 11 orthogonal factors, describing personality dimensions such as psychopathy, social anxiety and avoidance, negative affect and self-image. Factor analysis at the subscale-level identified two basic dimensions, reflecting hostile (DSM-IV Cluster B) and anxious (DSM-IV Cluster C) interpersonal attitudes. Categorical ADP-IV diagnoses are obtained using scoring algorithms, which emphasize the Trait or the Distress concepts in the diagnostic evaluation. Prevalences of ADP-IV diagnoses of any personality disorder according to these algorithms vary between 2.28 and 20.64%. Although further research in clinical samples is required, the present results support the validity of the ADP-IV and the potential of the measurement of trait and distress characteristics as a method for assessing personality pathology.

Identification of type IV collagen exposure as a molecular imaging target for early detection of thoracic aortic dissection

PubMed Central

Xu, Ke; Xu, Chen; Zhang, Yanzhenzi; Qi, Feiran; Yu, Bingran; Li, Ping; Jia, Lixin; Li, Yulin; Xu, Fu-jian; Du, Jie

2018-01-01

Thoracic aortic dissection (TAD) is an aggressive and life-threatening vascular disease and there is no effective means of early diagnosis of dissection. Type IV collagen (Col-IV) is a major component of the sub-endothelial basement membrane, which is initially exposed followed by endothelial injury as early-stage event of TAD. So, we want to build a noninvasive diagnostic method to detect early dissection by identifying the exposed Col-IV via MRI. Methods: Col-IV-targeted magnetic resonance/ fluorescence dual probe (Col-IV-DOTA-Gd-rhodamine B; CDR) was synthesized by amide reaction and coordination reaction. Flow cytometry analysis was used to evaluate the cell viability of SMC treated with CDR and fluorescence assays were used to assess the Col-IV targeting ability of CDR in vitro. We then examined the sensitivity and specificity of CDR at different stages of TAD via MRI and bioluminescence imaging in vivo. Results: The localization of Col-IV (under the intima) was observed by histology images. CDR bound specifically to Col-IV-expressing vascular smooth muscle cells and BAPN-induced dissected aorta. The CDR signal was co-detected by magnetic resonance imaging (MRI) and bioluminescence imaging as early as 2 weeks after BAPN administration (pre-dissection stage). The ability to detect rupture of dissected aorta was indicated by a strong normalized signal enhancement (NSE) in vivo. Moreover, NSE was negatively correlated with the time of dissection rupture after BAPN administration (r2 = 0.8482). Conclusion: As confirmed by in vivo studies, the CDR can identify the exposed Col-IV in degenerated aorta to monitor the progress of aortic dissection from the early stage to the rupture via MRI. Thus, CDR-enhanced MRI proposes a potential method for dissection screening, and for monitoring disease progression and therapeutic response. PMID:29290819

Method of preparation of uranium nitride

DOEpatents

Kiplinger, Jaqueline Loetsch; Thomson, Robert Kenneth James

2013-07-09

Method for producing terminal uranium nitride complexes comprising providing a suitable starting material comprising uranium; oxidizing the starting material with a suitable oxidant to produce one or more uranium(IV)-azide complexes; and, sufficiently irradiating the uranium(IV)-azide complexes to produce the terminal uranium nitride complexes.

Simultaneous spectrophotometric determination of trace amounts of uranium, thorium, and zirconium using the partial least squares method after their preconcentration by alpha-benzoin oxime modified Amberlite XAD-2000 resin.

PubMed

Ghasemi, Jahan B; Zolfonoun, E

2010-01-15

A new solid phase extraction method for separation and preconcentration of trace amounts of uranium, thorium, and zirconium in water samples is proposed. The procedure is based on the adsorption of U(VI), Th(IV) and Zr(IV) ions on a column of Amberlite XAD-2000 resin loaded with alpha-benzoin oxime prior to their simultaneous spectrophotometric determination with Arsenazo III using orthogonal signal correction partial least squares method. The enrichment factor for preconcentration of uranium, thorium, and zirconium was found to be 100. The detection limits for U(VI), Th(IV) and Zr(IV) were 0.50, 0.54, and 0.48microgL(-1), respectively. The precision of the method, evaluated as the relative standard deviation obtained by analyzing a series of 10 replicates, was below 4% for all elements. The practical applicability of the developed sorbent was examined using synthetic seawater, natural waters and ceramic samples.

Shunt resistance and saturation current determination in CdTe and CIGS solar cells. Part 2: application to experimental IV measurements and comparison with other methods

NASA Astrophysics Data System (ADS)

Rangel-Kuoppa, Victor-Tapio; Albor-Aguilera, María-de-Lourdes; Hérnandez-Vásquez, César; Flores-Márquez, José-Manuel; Jiménez-Olarte, Daniel; Sastré-Hernández, Jorge; González-Trujillo, Miguel-Ángel; Contreras-Puente, Gerardo-Silverio

2018-04-01

In this Part 2 of this series of articles, the procedure proposed in Part 1, namely a new parameter extraction technique of the shunt resistance (R sh ) and saturation current (I sat ) of a current-voltage (I-V) measurement of a solar cell, within the one-diode model, is applied to CdS-CdTe and CIGS-CdS solar cells. First, the Cheung method is used to obtain the series resistance (R s ) and the ideality factor n. Afterwards, procedures A and B proposed in Part 1 are used to obtain R sh and I sat . The procedure is compared with two other commonly used procedures. Better accuracy on the simulated I-V curves used with the parameters extracted by our method is obtained. Also, the integral percentage errors from the simulated I-V curves using the method proposed in this study are one order of magnitude smaller compared with the integral percentage errors using the other two methods.

[Crops: Classifying, Selecting, Harvesting, Grading, and Packing.] Student Materials. V.A. III. [IV-B-1 through IV-B-2; IV-C-1 through IV-C-2].

ERIC Educational Resources Information Center

Texas A and M Univ., College Station. Vocational Instructional Services.

Part of a series of eight student learning modules in vocational agriculture, this booklet deals with crop-related activities. The first section is on harvesting methods and equipment. The following portions address the handling, grading, and packing of crops; and the classification and selection of fruits, vegetables, and ornamental plants. There…

Adsorption study of selenium ions from aqueous solutions using MgO nanosheets synthesized by ultrasonic method

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

Cui, Wenwen; Li, Ping; Wang, Zheming

tMgO nanosheets with thickness ranges of 3–10 molecule layers and high specific area (166.44 m2g-1)were successfully fabricated by an ultrasound-assisted exfoliation method and used as adsorbent forthe removal of both selenite (Se(IV)) and selenate (Se(VI)) from aqueous solutions. The resulting MgOnanosheets displayed high maximum adsorption capacities of 103.52 and 10.28 mg g-1for Se(IV) andSe(VI), respectively. ATR-FTIR and XPS spectroscopic results suggested that both Se(IV) and Se(VI) formedinner-sphere surface complexes on MgO nanosheets under the present experimental conditions. Fur-thermore, high adsorption capacity for Se(IV/VI) in the presence of coexistent anions (SO 4 2-, PO43-, Cl-,and F-) and efficient regeneratability of adsorbentmore » by NaOH solution were observed in the competitiveadsorption and regeneration steps. The simple one-step synthesis process of MgO nanosheets and highadsorption capacities offer a promising method for Se(IV/VI) removal in water treatment.« less

Performing both propensity score and instrumental variable analyses in observational studies often leads to discrepant results: a systematic review.

PubMed

Laborde-Castérot, Hervé; Agrinier, Nelly; Thilly, Nathalie

2015-10-01

Propensity score (PS) and instrumental variable (IV) are analytical techniques used to adjust for confounding in observational research. More and more, they seem to be used simultaneously in studies evaluating health interventions. The present review aimed to analyze the agreement between PS and IV results in medical research published to date. Review of all published observational studies that evaluated a clinical intervention using simultaneously PS and IV analyses, as identified in MEDLINE and Web of Science. Thirty-seven studies, most of them published during the previous 5 years, reported 55 comparisons between results from PS and IV analyses. There was a slight/fair agreement between the methods [Cohen's kappa coefficient = 0.21 (95% confidence interval: 0.00, 0.41)]. In 23 cases (42%), results were nonsignificant for one method and significant for the other, and IV analysis results were nonsignificant in most situations (87%). Discrepancies are frequent between PS and IV analyses and can be interpreted in various ways. This suggests that researchers should carefully consider their analytical choices, and readers should be cautious when interpreting results, until further studies clarify the respective roles of the two methods in observational comparative effectiveness research. Copyright © 2015 Elsevier Inc. All rights reserved.

Three insulation methods to minimize intravenous fluid administration set heat loss.

PubMed

Piek, Richardt; Stein, Christopher

2013-01-01

To assess the effect of three methods for insulating an intravenous (IV) fluid administration set on the temperature of warmed fluid delivered rapidly in a cold environment. The three chosen techniques for insulation of the IV fluid administration set involved enclosing the tubing of the set in 1) a cotton conforming bandage, 2) a reflective emergency blanket, and 3) a combination of technique 2 followed by technique 1. Intravenous fluid warmed to 44°C was infused through a 20-drop/mL 180-cm-long fluid administration set in a controlled environmental temperature of 5°C. Temperatures in the IV fluid bag, the distal end of the fluid administration set, and the environment were continuously measured with resistance thermosensors. Twenty repetitions were performed in four conditions, namely, a control condition (with no insulation) and the three different insulation methods described above. One-way analysis of variance was used to assess the mean difference in temperature between the IV fluid bag and the distal fluid administration set under the four conditions. In the control condition, a mean of 5.28°C was lost between the IV fluid bag and the distal end of the fluid administration set. There was a significant difference found between the four conditions (p < 0.001). A mean of 3.53°C was lost between the IV fluid bag and the distal end of the fluid administration set for both the bandage and reflective emergency blanket, and a mean of 3.06°C was lost when the two methods were combined. Using inexpensive and readily available materials to insulate a fluid administration set can result in a reduction of heat loss in rapidly infused, warmed IV fluid in a cold environment.

A comparison of delirium diagnosis in elderly medical inpatients using the CAM, DRS-R98, DSM-IV and DSM-5 criteria.

PubMed

Adamis, Dimitrios; Rooney, Siobhan; Meagher, David; Mulligan, Owen; McCarthy, Geraldine

2015-06-01

The recently published DSM-5 criteria for delirium may lead to different case identification and rates of delirium than previous classifications. The aims of this study are to determine how the new DSM-5 criteria compare with DSM-IV in identification of delirium in elderly medical inpatients and to investigate the agreement between different methods, using CAM, DRS-R98, DSM-IV, and DSM-5 criteria. Prospective, observational study of elderly patients aged 70+ admitted under the acute medical teams in a regional general hospital. Each participant was assessed within 3 days of admission using the DSM-5, and DSM-IV criteria plus the DRS-R98, and CAM scales. We assessed 200 patients [mean age 81.1±6.5; 50% female; pre-existing cognitive impairment in 63%]. The prevalence rates of delirium for each diagnostic method were: 13.0% (n = 26) for DSM-5; 19.5% (n = 39) for DSM-IV; 13.5% (n = 27) for DRS-R98 and 17.0%, (n = 34) for CAM. Using tetrachoric correlation coefficients the agreement between DSM-5 and DSM-IV was statistically significant (ρtetr = 0.64, SE = 0.1, p < 0.0001). Similar significant agreement was found between the four methods. DSM-IV is the most inclusive diagnostic method for delirium, while DSM-5 is the most restrictive. In addition, these classification systems identify different cases of delirium. This could have clinical, financial, and research implications. However, both classification systems have significant agreement in the identification of the same concept (delirium). Clarity of diagnosis is required for classification but also further research considering the relevance in predicting outcomes can allow for more detailed evaluation of the DSM-5 criteria.

Infusion volume control and calculation using metronome and drop counter based intravenous infusion therapy helper.

PubMed

Park, Kyungnam; Lee, Jangyoung; Kim, Soo-Young; Kim, Jinwoo; Kim, Insoo; Choi, Seung Pill; Jeong, Sikyung; Hong, Sungyoup

2013-06-01

This study assessed the method of fluid infusion control using an IntraVenous Infusion Controller (IVIC). Four methods of infusion control (dial flow controller, IV set without correction, IV set with correction and IVIC correction) were used to measure the volume of each technique at two infusion rates. The infused fluid volume with a dial flow controller was significantly larger than other methods. The infused fluid volume was significantly smaller with an IV set without correction over time. Regarding the concordance correlation coefficient (CCC) of infused fluid volume in relation to a target volume, IVIC correction was shown to have the highest level of agreement. The flow rate measured in check mode showed a good agreement with the volume of collected fluid after passing through the IV system. Thus, an IVIC could assist in providing an accurate infusion control. © 2013 Wiley Publishing Asia Pty Ltd.

Solving the Jigsaw Puzzle of Wound-Healing Potato Cultivars: Metabolite Profiling and Antioxidant Activity of Polar Extracts

PubMed Central

2015-01-01

Potato (Solanum tuberosum L.) is a worldwide food staple, but substantial waste accompanies the cultivation of this crop due to wounding of the outer skin and subsequent unfavorable healing conditions. Motivated by both economic and nutritional considerations, this metabolite profiling study aims to improve understanding of closing layer and wound periderm formation and guide the development of new methods to ensure faster and more complete healing after skin breakage. The polar metabolites of wound-healing tissues from four potato cultivars with differing patterns of tuber skin russeting (Norkotah Russet, Atlantic, Chipeta, and Yukon Gold) were analyzed at three and seven days after wounding, during suberized closing layer formation and nascent wound periderm development, respectively. The polar extracts were assessed using LC-MS and NMR spectroscopic methods, including multivariate analysis and tentative identification of 22 of the 24 biomarkers that discriminate among the cultivars at a given wound-healing time point or between developmental stages. Differences among the metabolites that could be identified from NMR- and MS-derived biomarkers highlight the strengths and limitations of each method, also demonstrating the complementarity of these approaches in terms of assembling a complete molecular picture of the tissue extracts. Both methods revealed that differences among the cultivar metabolite profiles diminish as healing proceeds during the period following wounding. The biomarkers included polyphenolic amines, flavonoid glycosides, phenolic acids and glycoalkaloids. Because wound healing is associated with oxidative stress, the free radical scavenging activities of the extracts from different cultivars were measured at each wounding time point, revealing significantly higher scavenging activity of the Yukon Gold periderm especially after 7 days of wounding. PMID:24998264

The Development and Evaluation of Training Methods for Group IV Personnel. 1. Orientation and Implementation of the Training Methods Development School (TMDS).

ERIC Educational Resources Information Center

Steinemann, John H.

The investigation is part of continuing Navy research on the Trainability of Group IV (low ability) personnel intended to maximize the utilization and integration of marginal personnel in the fleet. An experimental Training Methods Development School (TMDS) was initiated to provide an experimental training program, with research controls, for…

Co-modification of amorphous-Ti(IV) hole cocatalyst and Ni(OH)2 electron cocatalyst for enhanced photocatalytic H2-production performance of TiO2

NASA Astrophysics Data System (ADS)

Wang, Ping; Lu, Yanggang; Wang, Xuefei; Yu, Huogen

2017-01-01

Highly efficient TiO2 photocatalysts co-modified by amorphous-Ti(IV) hole cocatalyst and Ni(OH)2 electron cocatalyst (referred to as Ni(OH)2-Ti(IV)/TiO2) were prepared by facile two-step process which was the initial formation of amorphous Ti(IV) on the TiO2 surface via hydrolysis method and the following formation of Ni(OH)2 via precipitation reaction. It was found that the Ni(OH)2-Ti(IV)/TiO2 showed obviously high hydrogen-production performance. When the amount of Ni(OH)2 and Ti(IV) was 1 wt% and 0.1 wt%, respectively, the hydrogen-production rate of the resultant Ni(OH)2-Ti(IV)/TiO2 reached 7280.04 μmol h-1 g-1, which was significantly higher than that of TiO2, Ti(IV)/TiO2 and Ni(OH)2/TiO2 by a factor of 215, 63 and 1.8, respectively. Moreover, it was found that Ni(OH)2-Ti(IV)/TiO2 photocatalyst preserved a steady and highly efficient H2-production performance during repeated tests and also exhibited a high transient photocurrent density. The enhanced hydrogen-production performance of Ni(OH)2-Ti(IV)/TiO2 can be attributed to the synergistic effect of Ti(IV) hole cocatalyst and Ni(OH)2 electron cocatalyst to simultaneously accelerate the interfacial transfer of photogenerated holes and electrons. The present surface modification of dual cocatalysts can be regarded as one of the ideal strategies for the preparation of highly efficient hydrogen-production materials in view of their abundance, low cost and facile method.

Method of synthesis of anhydrous thorium(IV) complexes

DOEpatents

Kiplinger, Jaqueline L; Cantat, Thibault

2013-04-30

Method of producing anhydrous thorium(IV) tetrahalide complexes, utilizing Th(NO.sub.3).sub.4(H.sub.2O).sub.x, where x is at least 4, as a reagent; method of producing thorium-containing complexes utilizing ThCl.sub.4(DME).sub.2 as a precursor; method of producing purified ThCl.sub.4(ligand).sub.x compounds, where x is from 2 to 9; and novel compounds having the structures: ##STR00001##

Integration of preclinical and clinical knowledge to predict intravenous PK in human: bilastine case study.

PubMed

Vozmediano, Valvanera; Ortega, Ignacio; Lukas, John C; Gonzalo, Ana; Rodriguez, Monica; Lucero, Maria Luisa

2014-03-01

Modern pharmacometrics can integrate and leverage all prior proprietary and public knowledge. Such methods can be used to scale across species or comparators, perform clinical trial simulation across alternative designs, confirm hypothesis and potentially reduce development burden, time and costs. Crucial yet typically lacking in integration is the pre-clinical stage. Prediction of PK in man, using in vitro and in vivo studies in different animal species, is increasingly well theorized but could still find wider application in drug development. The aim of the present work was to explore methods for bridging pharmacokinetic knowledge from animal species (i.v. and p.o.) and man (p.o.) into i.v. in man using the antihistamine drug bilastine as example. A model, predictive of i.v. PK in man, was developed on data from two pre-clinical species (rat and dog) and p.o. in man bilastine trials performed earlier. In the knowledge application stage, two different approaches were used to predict human plasma concentration after i.v. of bilastine: allometry (several scaling methods) and a semi-physiological method. Both approaches led to successful predictions of key i.v. PK parameters of bilastine in man. The predictive i.v. PK model was validated using later data from a clinical study of i.v. bilastine. Introduction of such knowledge in development permits proper leveraging of all emergent knowledge as well as quantification-based exploration of PK scenario, e.g. in special populations (pediatrics, renal insufficiency, comedication). In addition, the methods permit reduction or elimination and certainly optimization of learning trials, particularly those concerning alternative off-label administration routes.

Asian American parents' attributions of children with Down syndrome: connections with child characteristics and culture.

PubMed

Ly, Tran M

2008-04-01

This study explores cultural differences between European American (n = 26) and Asian American (n = 17) parents' attributional ratings of children with Down syndrome. Links were examined among parents' attributions, reactions, and behaviors regarding their child's jigsaw-puzzle performance. Although the children's puzzle abilities did not differ, compared with European American parents, Asian American parents judged their child as less successful and had lower expectations for future success. Asian American parents also attributed the child's performance to lower ability and lower effort. Affectively, they indicated less sympathy and more anger and blame toward the child. Despite striking ethnic differences, parents in both groups judged their older children as more successful and reported offering them less encouragement and help. Implications of these findings are discussed.

Discovering a vaccine against neosporosis using computers: is it feasible?

PubMed

Goodswen, Stephen J; Kennedy, Paul J; Ellis, John T

2014-08-01

A vaccine is urgently needed to prevent cattle neosporosis. This infectious disease is caused by the parasite Neospora caninum, a complex biological system with multifaceted life cycles. An in silico vaccine discovery approach attempts to transform digital abstractions of this system into adequate knowledge to predict candidates. Researchers need current information to implement such an approach, such as understanding evasion mechanisms of the immune system, type of immune response to elicit, availability of data and prediction programs, and statistical models to analyze predictions. Taken together, an in silico approach involves assembly of an intricate jigsaw of interdisciplinary and interdependent knowledge. In this review, we focus on the approach influencing vaccine development against Neospora caninum, which can be generalized to other pathogenic apicomplexans. Copyright © 2014 Elsevier Ltd. All rights reserved.

Molecular mechanisms controlling pavement cell shape in Arabidopsis leaves.

PubMed

Qian, Pingping; Hou, Suiwen; Guo, Guangqin

2009-08-01

Pavement cells have an interlocking jigsaw puzzle-shaped leaf surface pattern. Twenty-three genes involved in the pavement cell morphogenesis were discovered until now. The mutations of these genes through various means lead to pavement cell shape defects, such as loss or lack of interdigitation, the reduction of lobing, gaps between lobe and neck regions in pavement cells, and distorted trichomes. These phenotypes are affected by the organization of microtubules and microfilaments. Microtubule bands are considered corresponding with the neck regions of the cell, while lobe formation depends on patches of microfilaments. The pathway of Rho of plant (ROP) GTPase signaling cascades regulates overall activity of the cytoskeleton in pavement cells. Some other proteins, in addition to the ROPs, SCAR/WAVE, and ARP2/3 complexes, are also involved in the pavement cell morphogenesis.

LobeFinder: A Convex Hull-Based Method for Quantitative Boundary Analyses of Lobed Plant Cells1[OPEN

PubMed Central

Wu, Tzu-Ching; Belteton, Samuel A.; Szymanski, Daniel B.; Umulis, David M.

2016-01-01

Dicot leaves are composed of a heterogeneous mosaic of jigsaw puzzle piece-shaped pavement cells that vary greatly in size and the complexity of their shape. Given the importance of the epidermis and this particular cell type for leaf expansion, there is a strong need to understand how pavement cells morph from a simple polyhedral shape into highly lobed and interdigitated cells. At present, it is still unclear how and when the patterns of lobing are initiated in pavement cells, and one major technological bottleneck to addressing the problem is the lack of a robust and objective methodology to identify and track lobing events during the transition from simple cell geometry to lobed cells. We developed a convex hull-based algorithm termed LobeFinder to identify lobes, quantify geometric properties, and create a useful graphical output of cell coordinates for further analysis. The algorithm was validated against manually curated images of pavement cells of widely varying sizes and shapes. The ability to objectively count and detect new lobe initiation events provides an improved quantitative framework to analyze mutant phenotypes, detect symmetry-breaking events in time-lapse image data, and quantify the time-dependent correlation between cell shape change and intracellular factors that may play a role in the morphogenesis process. PMID:27288363

Sensitive method for the determination of different S(IV) species in cloud and fog water.

PubMed

Lammel, G

1996-08-01

Suppressed ion chromatography has been applied to the determination of S(IV) species in cloud and fog water in the range 0.012-2.4 mg S(IV)-S/L. The samples have been preserved prior to storage and S(IV) species have been determined as hydroxy methanesulfonate (HMS) together with the low molecular weight carboxylic acid anions, formate and acetate. Samples have been divided and treated differently such that total S(IV) as well as the non-oxidizable fraction of S(IV) (as given by the reactivity with H(2)O(2), added in surplus) could be determined. The difference between the two corresponds to the S(IV) fraction subjected to oxididation, which is of paramount interest in cloud and fogwater chemistry.

Andromeda IV: A new local volume very metal-poor galaxy

NASA Astrophysics Data System (ADS)

Pustilnik, S. A.; Tepliakova, A. L.; Kniazev, A. Y.; Burenkov, A. N.

2008-06-01

And IV is a low surface brightness (LSB) dwarf galaxy at a distance of 6.1 Mpc, projecting close to M 31. In this paper the results of spectroscopy of the And IV two brightest HII regions with the SAO 6-m telescope (BTA) are presented. In spectra of both of them the faint line [OIII] λ4363 Å was detected and this allowed us to determine their O/H by the classical Te method. Their values for 12+log(O/H) are equal to 7.49±0.06 and 7.55±0.23, respectively. The comparison of the direct O/H calculations with the two most reliable semi-empirical and empirical methods shows the good consistency between these methods. For And IV absolute blue magnitude, MB = -12.6, our value for O/H corresponds to the ‘standard’ relation between O/H and LB for dwarf irregular galaxies (DIGs). And IV appears to be a new representative of the extremely metal-deficient gas-rich galaxies in the Local Volume. The very large range of M(HI) for LSB galaxies with close metallicities and luminosities indicates that simple models of LSBG chemical evolution are too limited to predict such striking diversity.

Simultaneous speciation of inorganic arsenic, selenium and tellurium in environmental water samples by dispersive liquid liquid microextraction combined with electrothermal vaporization inductively coupled plasma mass spectrometry.

PubMed

Liu, Ying; He, Man; Chen, Beibei; Hu, Bin

2015-09-01

A new method based on dispersive liquid liquid microextraction (DLLME) combined with electrothermal vaporization inductively coupled plasma mass spectrometry (ETV-ICP-MS) was developed for the simultaneous speciation of inorganic arsenic (As), selenium (Se) and tellurium (Te) with sodium diethyldithiocarbamate (DDTC) as both chelating reagent and chemical modifier. As(III), Se(IV) and Te(IV) were transformed into DDTC-chelates at pH 7 and extracted into the fine droplets formed by injecting the binary solution of bromobenzene (extraction solvent) and methanol (dispersive solvent) into the sample solution. After phase separation by centrifugation, As(III), Se(IV) and Te(IV) preconcentrated in the organic phase were determined by ETV-ICP-MS. Total inorganic As, Se and Te were obtained by reducing As(V), Se(VI) and Te(VI) to As(III), Se(IV) and Te(IV) with L-cysteine, which were then subjected to the same DLLME-ETV-ICP-MS process. The concentration of As(V), Se(VI), Te(VI) were calculated by subtracting the concentration of As(III), Se(IV) and Te(IV) from the total inorganic As, Se and Te, respectively. The main factors affecting the microextraction efficiency and the vaporization behavior of target species were investigated in detail. Under the optimal conditions, the limits of detection were 2.5, 8.6 and 0.56 ng L(-1) for As(III), Se(IV) and Te(IV), respectively, with the relative standard deviations (n=7) of 8.5-9.7%. The developed method was applied to the speciation of inorganic As, Se and Te in Certified Reference Materials of GSBZ50004-88, GBW(E)080395 and GBW(E)080548 environmental waters, and the determined values are in good agreement with the certified values. The method was also successfully applied to the simultaneous speciation of inorganic As, Se and Te in different environmental water samples with the recoveries in the range of 86.3-107% for the spiked samples. Copyright © 2015 Elsevier B.V. All rights reserved.

Reliability of DSM-IV Symptom Ratings of ADHD: Implications for DSM-V

ERIC Educational Resources Information Center

Solanto, Mary V.; Alvir, Jose

2009-01-01

Objective: The objective of this study was to examine the intrarater reliability of "DSM-IV" ADHD symptoms. Method: Two-hundred-two children referred for attention problems and 49 comparison children (all 7-12 years) were rated by parents and teachers on the identical "DSM-IV" items presented in two different formats, the…

40 CFR Appendix IV to Part 261 - Reserved

Code of Federal Regulations, 2010 CFR

2010-07-01

... AND LISTING OF HAZARDOUS WASTE Financial Requirements for Management of Excluded Hazardous Secondary Materials Wording of the instruments. Appendix IV to Part 261 [Reserved for Radioactive Waste Test Methods] ...

Solid-phase extraction of iridium from soil and water samples by using activated carbon cloth prior to its spectrophotometric determination.

PubMed

Ozkantar, Nebiye; Yilmaz, Erkan; Soylak, Mustafa; Tuzen, Mustafa

2015-08-01

A solid-phase extraction method for separation and preconcentration of Ir(IV) ion by using activated carbon cloth (ACC) has been presented. Ir(IV) as their 1-(2-pyridylazo) 2-naphtol (PAN) chelate was adsorbed on ACC at pH 2.0 and was eluted from ACC with acidic dimethylformamide (DMF). The Ir(IV) concentration was determined at 536 nm as Ir(IV)-PAN complex by using UV-vis spectrophotometer. The analytical parameters including pH, sample and eluent flow rates, amount of PAN, eluent type, concentration, and sample volume were optimized. The effects of foreign ions on the recoveries of iridium were also investigated. The preconcentration factor was calculated as 60. The limit of detection (LOD) and the limit of quantification (LOQ) of the method were found as 0.039 and 0.129 μg L(-1), respectively. The method was applied to soil and water samples for iridium determination.

Textural variations and fragmentation processes in peperite formed between felsic lava flow and wet substrate: An example from the Cretaceous Buan Volcanics, southwest Korea

NASA Astrophysics Data System (ADS)

Gihm, Yong Sik; Kwon, Chang Woo

2017-02-01

Multiple exposures of peperite within the Cretaceous Buan Volcanics, southwest Korea, have been examined in order to determine variations in their textural characteristics and to investigate their mode of formation. Along undulating boundaries between rhyolite (lava flow) and deformed host sediment expressed as a series of load and flame structures, exposures commonly contain two distinct types of peperite. Type-1 peperites are composed mostly of rounded juvenile clasts at their base and polyhedral juvenile clasts at their upper levels, interpreted to have formed via a two-stage process. Firstly, abrasion of juvenile clasts occurred after their fragmentation due to shear stress imparted by the overlying and still-moving lava flow, forming rounded juvenile clasts. Subsequent in situ quenching fragmentation of the lava flow produced clasts with platy to polyhedral shapes immediately after emplacement of the lava flow. Type-2 peperites laterally extend into the interior of featureless rhyolite as layers that decrease in thickness with increasing distance away from the flame zone. These layers exhibit horizontal textural variations, ranging from poorly sorted mixtures of ash- to block-sized angular juvenile clasts in the proximal zone, to closely packed polyhedral and tabular juvenile clasts with jigsaw-crack textures in the middle and distal zones. Type-2 peperite are inferred to have formed due to internal steam explosions that resulted from an expansion of heated pore water (leading to an increase in pore fluid pressure) that had been vertically injected into the interior of the rhyolite from the flame zone. The proximal zone, composed mainly of poorly sorted mixtures of juvenile clasts, represents the explosion sites. Juvenile clasts in the middle and distal zones are interpreted to have formed due to three separate processes: the development of fractures in the rhyolite during the internal steam explosions, injection of the host sediment through the fractures, and in situ quenching fragmentation. Deformation of the host sediment exerted an important control on peperite-forming processes, with the internal steam explosions suggested to have formed the closely packed, juvenile clasts with a jigsaw-crack texture rather than the clasts that are widely dispersed.

Characterization of cardiac quiescence from retrospective cardiac computed tomography using a correlation-based phase-to-phase deviation measure

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

Wick, Carson A.; McClellan, James H.; Arepalli, Chesnal D.

2015-02-15

Purpose: Accurate knowledge of cardiac quiescence is crucial to the performance of many cardiac imaging modalities, including computed tomography coronary angiography (CTCA). To accurately quantify quiescence, a method for detecting the quiescent periods of the heart from retrospective cardiac computed tomography (CT) using a correlation-based, phase-to-phase deviation measure was developed. Methods: Retrospective cardiac CT data were obtained from 20 patients (11 male, 9 female, 33–74 yr) and the left main, left anterior descending, left circumflex, right coronary artery (RCA), and interventricular septum (IVS) were segmented for each phase using a semiautomated technique. Cardiac motion of individual coronary vessels as wellmore » as the IVS was calculated using phase-to-phase deviation. As an easily identifiable feature, the IVS was analyzed to assess how well it predicts vessel quiescence. Finally, the diagnostic quality of the reconstructed volumes from the quiescent phases determined using the deviation measure from the vessels in aggregate and the IVS was compared to that from quiescent phases calculated by the CT scanner. Three board-certified radiologists, fellowship-trained in cardiothoracic imaging, graded the diagnostic quality of the reconstructions using a Likert response format: 1 = excellent, 2 = good, 3 = adequate, 4 = nondiagnostic. Results: Systolic and diastolic quiescent periods were identified for each subject from the vessel motion calculated using the phase-to-phase deviation measure. The motion of the IVS was found to be similar to the aggregate vessel (AGG) motion. The diagnostic quality of the coronary vessels for the quiescent phases calculated from the aggregate vessel (P{sub AGG}) and IVS (P{sub IV} {sub S}) deviation signal using the proposed methods was comparable to the quiescent phases calculated by the CT scanner (P{sub CT}). The one exception was the RCA, which improved for P{sub AGG} for 18 of the 20 subjects when compared to P{sub CT} (P{sub CT} = 2.48; P{sub AGG} = 2.07, p = 0.001). Conclusions: A method for quantifying the motion of specific coronary vessels using a correlation-based, phase-to-phase deviation measure was developed and tested on 20 patients receiving cardiac CT exams. The IVS was found to be a suitable predictor of vessel quiescence. The diagnostic quality of the quiescent phases detected by the proposed methods was comparable to those calculated by the CT scanner. The ability to quantify coronary vessel quiescence from the motion of the IVS can be used to develop new CTCA gating techniques and quantify the resulting potential improvement in CTCA image quality.« less

77 FR 56138 - World Trade Center Health Program; Addition of Certain Types of Cancer to the List of WTC-Related...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-09-12

... of Rulemaking on Federal Agencies IV. Methods Used by the Administrator To Determine Whether To Add... [ssquf] Rare cancers The Administrator developed a hierarchy of methods (detailed in Section IV of this... treating 9/11- exposed patients; health and research organizations; the WTC Health Program Survivors...

A method of classification for multisource data in remote sensing based on interval-valued probabilities

NASA Technical Reports Server (NTRS)

Kim, Hakil; Swain, Philip H.

1990-01-01

An axiomatic approach to intervalued (IV) probabilities is presented, where the IV probability is defined by a pair of set-theoretic functions which satisfy some pre-specified axioms. On the basis of this approach representation of statistical evidence and combination of multiple bodies of evidence are emphasized. Although IV probabilities provide an innovative means for the representation and combination of evidential information, they make the decision process rather complicated. It entails more intelligent strategies for making decisions. The development of decision rules over IV probabilities is discussed from the viewpoint of statistical pattern recognition. The proposed method, so called evidential reasoning method, is applied to the ground-cover classification of a multisource data set consisting of Multispectral Scanner (MSS) data, Synthetic Aperture Radar (SAR) data, and digital terrain data such as elevation, slope, and aspect. By treating the data sources separately, the method is able to capture both parametric and nonparametric information and to combine them. Then the method is applied to two separate cases of classifying multiband data obtained by a single sensor. In each case a set of multiple sources is obtained by dividing the dimensionally huge data into smaller and more manageable pieces based on the global statistical correlation information. By a divide-and-combine process, the method is able to utilize more features than the conventional maximum likelihood method.

Comparison of variance estimators for meta-analysis of instrumental variable estimates

PubMed Central

Schmidt, AF; Hingorani, AD; Jefferis, BJ; White, J; Groenwold, RHH; Dudbridge, F

2016-01-01

Abstract Background: Mendelian randomization studies perform instrumental variable (IV) analysis using genetic IVs. Results of individual Mendelian randomization studies can be pooled through meta-analysis. We explored how different variance estimators influence the meta-analysed IV estimate. Methods: Two versions of the delta method (IV before or after pooling), four bootstrap estimators, a jack-knife estimator and a heteroscedasticity-consistent (HC) variance estimator were compared using simulation. Two types of meta-analyses were compared, a two-stage meta-analysis pooling results, and a one-stage meta-analysis pooling datasets. Results: Using a two-stage meta-analysis, coverage of the point estimate using bootstrapped estimators deviated from nominal levels at weak instrument settings and/or outcome probabilities ≤ 0.10. The jack-knife estimator was the least biased resampling method, the HC estimator often failed at outcome probabilities ≤ 0.50 and overall the delta method estimators were the least biased. In the presence of between-study heterogeneity, the delta method before meta-analysis performed best. Using a one-stage meta-analysis all methods performed equally well and better than two-stage meta-analysis of greater or equal size. Conclusions: In the presence of between-study heterogeneity, two-stage meta-analyses should preferentially use the delta method before meta-analysis. Weak instrument bias can be reduced by performing a one-stage meta-analysis. PMID:27591262

Involving postgraduate's students in undergraduate small group teaching promotes active learning in both

PubMed Central

Kalra, Ruchi; Modi, Jyoti Nath; Vyas, Rashmi

2015-01-01

Background: Lecture is a common traditional method for teaching, but it may not stimulate higher order thinking and students may also be hesitant to express and interact. The postgraduate (PG) students are less involved with undergraduate (UG) teaching. Team based small group active learning method can contribute to better learning experience. Aim: To-promote active learning skills among the UG students using small group teaching methods involving PG students as facilitators to impart hands-on supervised training in teaching and managerial skills. Methodology: After Institutional approval under faculty supervision 92 UGs and 8 PGs participated in 6 small group sessions utilizing the jigsaw technique. Feedback was collected from both. Observations: Undergraduate Feedback (Percentage of Students Agreed): Learning in small groups was a good experience as it helped in better understanding of the subject (72%), students explored multiple reading resources (79%), they were actively involved in self-learning (88%), students reported initial apprehension of performance (71%), identified their learning gaps (86%), team enhanced their learning process (71%), informal learning in place of lecture was a welcome change (86%), it improved their communication skills (82%), small group learning can be useful for future self-learning (75%). Postgraduate Feedback: Majority performed facilitation for first time, perceived their performance as good (75%), it was helpful in self-learning (100%), felt confident of managing students in small groups (100%), as facilitator they improved their teaching skills, found it more useful and better identified own learning gaps (87.5%). Conclusions: Learning in small groups adopting team based approach involving both UGs and PGs promoted active learning in both and enhanced the teaching skills of the PGs. PMID:26380201

The Use of Linear Instrumental Variables Methods in Health Services Research and Health Economics: A Cautionary Note

PubMed Central

Terza, Joseph V; Bradford, W David; Dismuke, Clara E

2008-01-01

Objective To investigate potential bias in the use of the conventional linear instrumental variables (IV) method for the estimation of causal effects in inherently nonlinear regression settings. Data Sources Smoking Supplement to the 1979 National Health Interview Survey, National Longitudinal Alcohol Epidemiologic Survey, and simulated data. Study Design Potential bias from the use of the linear IV method in nonlinear models is assessed via simulation studies and real world data analyses in two commonly encountered regression setting: (1) models with a nonnegative outcome (e.g., a count) and a continuous endogenous regressor; and (2) models with a binary outcome and a binary endogenous regressor. Principle Findings The simulation analyses show that substantial bias in the estimation of causal effects can result from applying the conventional IV method in inherently nonlinear regression settings. Moreover, the bias is not attenuated as the sample size increases. This point is further illustrated in the survey data analyses in which IV-based estimates of the relevant causal effects diverge substantially from those obtained with appropriate nonlinear estimation methods. Conclusions We offer this research as a cautionary note to those who would opt for the use of linear specifications in inherently nonlinear settings involving endogeneity. PMID:18546544

Assuring NASA's Safety and Mission Critical Software

NASA Technical Reports Server (NTRS)

Deadrick, Wesley

2015-01-01

What is IV&V? Independent Verification and Validation (IV&V) is an objective examination of safety and mission critical software processes and products. Independence: 3 Key parameters: Technical Independence; Managerial Independence; Financial Independence. NASA IV&V perspectives: Will the system's software: Do what it is supposed to do?; Not do what it is not supposed to do?; Respond as expected under adverse conditions?. Systems Engineering: Determines if the right system has been built and that it has been built correctly. IV&V Technical Approaches: Aligned with IEEE 1012; Captured in a Catalog of Methods; Spans the full project lifecycle. IV&V Assurance Strategy: The IV&V Project's strategy for providing mission assurance; Assurance Strategy is driven by the specific needs of an individual project; Implemented via an Assurance Design; Communicated via Assurance Statements.

40 CFR 63.5776 - Who implements and enforces this subpart?

Code of Federal Regulations, 2010 CFR

2010-07-01

... resin operations. (iii) § 63.5731(a)—Standards for resin and gel coat mixing operations. (iv) § 63.5734...)(2)(ii) and (f), the authority to approve alternatives to the test methods listed in paragraphs (b)(2)(i) through (iv) of this section is not delegated. (i) § 63.5719(b)—Method for determining whether an...

Group IV nanocrystals with ion-exchangeable surface ligands and methods of making the same

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

Wheeler, Lance M.; Nichols, Asa W.; Chernomordik, Boris D.

Methods are described that include reacting a starting nanocrystal that includes a starting nanocrystal core and a covalently bound surface species to create an ion-exchangeable (IE) nanocrystal that includes a surface charge and a first ion-exchangeable (IE) surface ligand ionically bound to the surface charge, where the starting nanocrystal core includes a group IV element.

Slope And Equation of Line: Teach And Analysis In Terms of Emotional Intelligence

NASA Astrophysics Data System (ADS)

Dewi, A. C.; Budiyono; Riyadi

2017-09-01

Slope and equation of line is a sub-material of algebra and is one that is difficult for students to understand. The purpose of this study is to understand and explore the slope and equation so that students feel easy and ultimately improve their academic achievement. Experimental research was conducted by applying Jigsaw II learning model and Teams Games Tournament (TGT) and improvement in emotional intelligence (EI). The study sample was students from 3 different schools who were selected stratified cluster random sampling. The results showed that there is no influence of learning model and EI on academic achievement. This can happen even in the learning process students feel happy and interest. Although research shows different results with most theories, but it is expected that this research can be a good reference for students, teachers, and other researchers.

The Puzzle of Science; Making Sense of Incomplete Information

NASA Astrophysics Data System (ADS)

Shorey, B. U.

2015-12-01

There are many topics within Earth science including evolution, historical geology, and climate change, which have gained the status of theory becuse they have overwhelming evidence, yet there is still fragmentary information which can frustrate a student from coming to solid conclusions. Using a jigsaw puzzle whose image has been hidden, and the pieces only given out sparingly, students go though the process of getting more information. How does one get more puzzle pieces and what is the interpretive process? Experience with this exercise demonstrates how students can sketch out an incredibly accurate conception of the "big picture", despite not having all the puzzle pieces. The goal of this talk is to give a complete tool kit to perform as a comprehensive lesson plan. Guiding questions and copies of lesson plans and materials are supplied for this exercise.

Quantitative analysis of microtubule orientation in interdigitated leaf pavement cells.

PubMed

Akita, Kae; Higaki, Takumi; Kutsuna, Natsumaro; Hasezawa, Seiichiro

2015-01-01

Leaf pavement cells are shaped like a jigsaw puzzle in most dicotyledon species. Molecular genetic studies have identified several genes required for pavement cells morphogenesis and proposed that microtubules play crucial roles in the interdigitation of pavement cells. In this study, we performed quantitative analysis of cortical microtubule orientation in leaf pavement cells in Arabidopsis thaliana. We captured confocal images of cortical microtubules in cotyledon leaf epidermis expressing GFP-tubulinβ and quantitatively evaluated the microtubule orientations relative to the pavement cell growth axis using original image processing techniques. Our results showed that microtubules kept parallel orientations to the growth axis during pavement cell growth. In addition, we showed that immersion treatment of seed cotyledons in solutions containing tubulin polymerization and depolymerization inhibitors decreased pavement cell complexity. Treatment with oryzalin and colchicine inhibited the symmetric division of guard mother cells.

Using instrumental variables to estimate a Cox's proportional hazards regression subject to additive confounding

PubMed Central

Tosteson, Tor D.; Morden, Nancy E.; Stukel, Therese A.; O'Malley, A. James

2014-01-01

The estimation of treatment effects is one of the primary goals of statistics in medicine. Estimation based on observational studies is subject to confounding. Statistical methods for controlling bias due to confounding include regression adjustment, propensity scores and inverse probability weighted estimators. These methods require that all confounders are recorded in the data. The method of instrumental variables (IVs) can eliminate bias in observational studies even in the absence of information on confounders. We propose a method for integrating IVs within the framework of Cox's proportional hazards model and demonstrate the conditions under which it recovers the causal effect of treatment. The methodology is based on the approximate orthogonality of an instrument with unobserved confounders among those at risk. We derive an estimator as the solution to an estimating equation that resembles the score equation of the partial likelihood in much the same way as the traditional IV estimator resembles the normal equations. To justify this IV estimator for a Cox model we perform simulations to evaluate its operating characteristics. Finally, we apply the estimator to an observational study of the effect of coronary catheterization on survival. PMID:25506259

Using instrumental variables to estimate a Cox's proportional hazards regression subject to additive confounding.

PubMed

MacKenzie, Todd A; Tosteson, Tor D; Morden, Nancy E; Stukel, Therese A; O'Malley, A James

2014-06-01

The estimation of treatment effects is one of the primary goals of statistics in medicine. Estimation based on observational studies is subject to confounding. Statistical methods for controlling bias due to confounding include regression adjustment, propensity scores and inverse probability weighted estimators. These methods require that all confounders are recorded in the data. The method of instrumental variables (IVs) can eliminate bias in observational studies even in the absence of information on confounders. We propose a method for integrating IVs within the framework of Cox's proportional hazards model and demonstrate the conditions under which it recovers the causal effect of treatment. The methodology is based on the approximate orthogonality of an instrument with unobserved confounders among those at risk. We derive an estimator as the solution to an estimating equation that resembles the score equation of the partial likelihood in much the same way as the traditional IV estimator resembles the normal equations. To justify this IV estimator for a Cox model we perform simulations to evaluate its operating characteristics. Finally, we apply the estimator to an observational study of the effect of coronary catheterization on survival.

The 12-Month Prevalence of DSM-IV Anxiety Disorders among Nigerian Secondary School Adolescents Aged 13-18 Years

ERIC Educational Resources Information Center

Adewuya, Abiodun O.; Ola, Bola A.; Adewumi, Tomi A.

2007-01-01

Aims: To estimate the 12-month prevalence of DSM-IV-specific anxiety disorders among Nigerian secondary school adolescents aged 13-18 years. Method: A representative sample of adolescents (n=1090) from senior secondary schools in a semi-urban town in Nigeria was assessed for the 12-month prevalence of DSM-IV-specific anxiety. Results: The 12-month…

Poor Utility of the Age of Onset Criterion for DSM-IV Attention Deficit/Hyperactivity Disorder: Recommendations for DSM-V and ICD-11

ERIC Educational Resources Information Center

Todd, Richard D.; Huang, Hongyan; Henderson, Cynthia A.

2008-01-01

Background: To test whether the retrospective reporting of the age of onset impairment criterion for attention deficit/hyperactivity disorder (ADHD) required in the "Diagnostic and Statistical Manual of Mental Disorders-IV" (DSM-IV) complicates identification of new and known child and adolescent cases later in life. Methods: A birth-records-based…

Comparison of risk of malignancy index (RMI), CA125, CA 19-9, ultrasound score, and menopausal status in borderline ovarian tumor.

PubMed

Alanbay, Ibrahim; Akturk, Erhan; Coksuer, Hakan; Ercan, Mutlu; Karaşahin, Emre; Dede, Murat; Yenen, Mufit Cemal; Ozan, Hakan; Baser, Iskender

2012-06-01

The aim of this study was to assess the prognostic values of risk of malignancy index (RMI IV), ultrasound score, menopausal status, and serum CA125 and CA19-9 level in patients with borderline ovarian tumor (BOT). Fifty women having borderline ovarian tumor (BOT) and 5O individuals with benign adnexal mass were enrolled in this retrospective study. The sensitivity, specificity, positive predictive values, negative predictive values and diagnostic accuracy of preoperative serum levels of the CA125 and CA19-9, ultrasound findings and menopausal status, and RMI IV were calculated for prediction of discrimination between BOTs and benign adnexal masses and the results were compared. The RMI IV was the best method for discrimination between BOTs and benign adnexal masses and was more accurate than the other parameters. When Receiver Operator Characteristic area under the curves for menopausal status was analyzed, serum CA 125 and CA19-9 level, ultrasound score, RMI IV(CA125), and RMI IV(CA19-9) were, 0.580, 0.625, 0.548, 0.694, 0.734 and 0.711, respectively. The best RMI IV cut-off was found to be 200 for discrimination of benign and BOT lesions. In the RMI formulation, replacing CA125 with CA19-9 didn't affect RMI IV sensitivity and specificity for discrimination. Compared to ultrasound, menopausal status, CA-125, CA19-9, the RMI IV was found to be the best predictive method for differentiation of BOTs from benign adnexal masses. RMI IV cut-off value of 200 is suitable for differentiation of benign and BOT's.

Investigation of Pu(IV)-acetohydroxamic acid complex by solvent extraction with di(2-ethylhexyl) phosphoric acid

NASA Astrophysics Data System (ADS)

Brown, M. Alex; Paulenova, Alena; Tkac, Peter

2010-03-01

The stability constant of the Pu(IV)-acetohydroxamic acid complex Pu(AHA)3+ at 1 M ionic strength (pH = 0) has been investigated by method of solvent extraction. Di(2-ethylhexyl) phosphoric acid (HDEHP) was used to extract Pu(IV) from perchloric and nitric acid media at various AHA concentrations. Distribution ratios over a range of ligand concentrations were used in conjunction with graphical methods to obtain logβ1 = 14.3 ± 0.03 in perchloric acid. The stability constant determined from solutions in nitric acid was excluded because of the uncertainty in plutonium speciation.

Lunar crater depths from orbiter IV long-focus photographs

USGS Publications Warehouse

Arthur, D.W.G.

1974-01-01

The paper presents method and results for the determination of the depths of more than 1900 small lunar craters from measures of shadows on the long-focus pictures obtained by Lunar Orbiter IV. The method for converting the measured shadow length into the true length in nature of the shadow hypotenuse is new and is applicable to other planetary bodies provided comparable spacecraft ephemerides are available. The measures were made with a simple surveyor's plotting scale on the standard Orbiter IV photographic enlargements. The results indicate that the smaller lunar (D < 30 km) craters are appreciably deeper than is indicated by earlier work using imagery obtained at terrestrial observatories. ?? 1974.

Peripherally Inserted Central Catheter Placement with the Sonic Flashlight: Initial Clinical Trial by Nurses

PubMed Central

Wang, David; Amesur, Nikhil; Shukla, Gaurav; Bayless, Angela; Weiser, David; Scharl, Adam; Mockel, Derek; Banks, Christopher; Mandella, Bernadette; Klatzky, Roberta; Stetten, George

2010-01-01

Objective We describe a case series comprising the first clinical trial by intravenous (IV) team nurses using the Sonic Flashlight for ultrasound guidance of peripherally inserted central catheter (PICC) placement. Methods Two IV team nurses with more than 10 years experience placing PICCs and from 3–6 years experience with ultrasound (US) attempted to place PICCs under US guidance in patients requiring long-term IV access. One of two methods of US guidance was used: conventional ultrasound (CUS) (60 patients) or a new device called the Sonic Flashlight (SF) (44 patients). The number of needle punctures required to gain IV access was recorded for each subject. Results In both methods, 87% of the cases resulted in successful venous access on the first attempt. The average number of needle sticks per patient was 1.18 for SF-guided procedures, as compared to 1.20 for CUS-guided procedures. No significant difference was found in the distribution of the number of attempts between the two methods. Anecdotal comments by the nurses indicated the comparative ease of use of the SF display, although relatively small scale of the SF image compared to the CUS image was also noted. Conclusions We have shown that the Sonic Flashlight is a safe and effective device for guidance of PICC placement in the hands of experienced IV team nurses. The advantage of placing the ultrasound image at its actual location must be balanced against the relatively small scale of the SF image. PMID:19389904

Application of Cerium (IV) as an Oxidimetric Agent for the Determination of Ethionamide in Pharmaceutical Formulations

PubMed Central

2016-01-01

Two simple methods are described for the determination of ethionamide (ETM) in bulk drug and tablets using cerium (IV) sulphate as the oxidimetric agent. In both methods, the sample solution is treated with a measured excess of cerium (IV) solution in H2SO4 medium, and after a fixed standing time, the residual oxidant is determined either by back titration with standard iron (II) solution to a ferroin end point in titrimetry or by reacting with o-dianisidine followed by measurement of the absorbance of the orange-red coloured product at 470 nm in spectrophotometry. In titrimetry, the reaction proceeded with a stoichiometry of 1 : 2 (ETM : Ce (IV)) and the amount of cerium (IV) consumed by ETM was related to the latter's amount, and the method was applicable over 1.0–8.0 mg of drug. In spectrophotometry, Beer's law was obeyed over the concentration range of 0.5–5.0 μg/mL ETM with a molar absorptivity value of 2.66 × 104 L/(mol·cm). The limits of detection (LOD) and quantification (LOQ) calculated according to ICH guidelines were 0.013 and 0.043 μg/mL, respectively. The proposed titrimetric and spectrophotometric methods were found to yield reliable results when applied to bulk drug and tablets analysis, and hence they can be applied in quality control laboratories. PMID:27818836

Beyond the floor effect on the Wechsler Intelligence Scale for Children--4th Ed. (WISC-IV): calculating IQ and Indexes of subjects presenting a floored pattern of results.

PubMed

Orsini, A; Pezzuti, L; Hulbert, S

2015-05-01

It is now widely known that children with severe intellectual disability show a 'floor effect' on the Wechsler scales. This effect emerges because the practice of transforming raw scores into scaled scores eliminates any variability present in participants with low intellectual ability and because intelligence quotient (IQ) scores are limited insofar as they do not measure scores lower than 40. Following Hessl et al.'s results, the present authors propose a method for the computation of the Wechsler Intelligence Scale for Children--4th Ed. (WISC-IV)'s IQ and Indexes in intellectually disabled participants affected by a floored pattern of results. The Italian standardization sample (n = 2200) for the WISC-IV was used. The method presented in this study highlights the limits of the 'floor effect' of the WISC-IV in children with serious intellectual disability who present a profile with weighted scores of 1 in all the subtests despite some variability in the raw scores. Such method eliminates the floor effect of the scale and therefore makes it possible to analyse the strengths and weaknesses of the WISC-IV's Indexes in these participants. The Authors reflect on clinical utility of this method and on the meaning of raw score of 0 on subtest. © 2014 MENCAP and International Association of the Scientific Study of Intellectual and Developmental Disabilities and John Wiley & Sons Ltd.

Photoactivation of Diiodido-Pt(IV) Complexes Coupled to Upconverting Nanoparticles.

PubMed

Perfahl, Stefanie; Natile, Marta M; Mohamad, Heba S; Helm, Christiane A; Schulzke, Carola; Natile, Giovanni; Bednarski, Patrick J

2016-07-05

The preparation, characterization, and surface modification of upconverting lanthanide-doped hexagonal NaGdF4 nanocrystals attached to light sensitive diiodido-Pt(IV) complexes is presented. The evaluation for photoactivation and cytotoxicity of the novel carboxylated diiodido-Pt(IV) cytotoxic prodrugs by near-infrared (NIR) light (λ = 980 nm) is also reported. We attempted two different strategies for attachment of light-sensitive diiodido-Pt(IV) complexes to Yb,Er- and Yb,Tm-doped β-NaGdF4 upconverting nanoparticles (UCNPs) in order to provide nanohybrids, which offer unique opportunities for selective drug activation within the tumor cells and subsequent spatiotemporal controlled drug release by NIR-to-visible light-upconversion: (A) covalent attachment of the Pt(IV) complex via amide bond formation and (B) carboxylate exchange of oleate on the surface of the UCNPs with diiodido-Pt(IV) carboxylato complexes. Initial feasibility studies showed that NIR applied by a 980 nm laser had only a slight effect on the stability of the various diiodido-Pt(IV) complexes, but when UCNPs were present more rapid loss of the ligand-metal-charge transfer (LMCT) bands of the diiodido-Pt(IV) complexes was observed. Furthermore, Pt released from the Pt(IV) complexes platinated calf-thymus DNA (ct-DNA) more rapidly when NIR was applied compared to dark controls. Of the two attachment strategies, method A with the covalently attached diiodido-Pt(IV) carboxylates via amide bond formation proved to be the most effective method for generating UCNPs that release Pt when irradiated with NIR; the released Pt was also able to bind irreversibly to calf thymus DNA. Nonetheless, only ca. 20% of the Pt on the surface of the UCNPs was in the Pt(IV) oxidation state, the rest was Pt(II), indicating chemical reduction of the diiodido-Pt(IV) prodrug by the UCNPs. Cytotoxicity studies with the various UCNP-Pt conjugates and constructs, tested on human leukemia HL60 cells in culture, indicated a substantial increase in cytotoxicity when modified UCNPs were combined with five rounds of 30 min irradiation with NIR compared to dark controls, but NIR alone also had a significant cytotoxic effect at this duration.

Consensus in controversy: The modified Delphi method applied to Gynecologic Oncology practice.

PubMed

Cohn, David E; Havrilesky, Laura J; Osann, Kathryn; Lipscomb, Joseph; Hsieh, Susie; Walker, Joan L; Wright, Alexi A; Alvarez, Ronald D; Karlan, Beth Y; Bristow, Robert E; DiSilvestro, Paul A; Wakabayashi, Mark T; Morgan, Robert; Mukamel, Dana B; Wenzel, Lari

2015-09-01

To determine the degree of consensus regarding the probabilities of outcomes associated with IP/IV and IV chemotherapy. A survey was administered to an expert panel using the Delphi method. Ten ovarian cancer experts were asked to estimate outcomes for patients receiving IP/IV or IV chemotherapy. The clinical estimates were: 1) probability of completing six cycles of chemotherapy, 2) probability of surviving five years, 3) median survival, and 4) probability of ER/hospital visits during treatment. Estimates for two patients, one with a low comorbidity index (patient 1) and the other with a moderate index (patient 2), were included. The survey was administered in three rounds, and panelists could revise their subsequent responses based on review of the anonymous opinions of their peers. The ranges were smaller for IV compared with IP/IV therapy. Ranges decreased with each round. Consensus converged around outcomes related to IP/IV chemotherapy for: 1) completion of 6 cycles of therapy (type 1 patient, 62%, type 2 patient, 43%); 2) percentage of patients surviving 5 years (type 1 patient, 66%, type 2 patient, 47%); and 3) median survival (type 1 patient, 83 months, type 2 patient, 58 months). The group required three rounds to achieve consensus on the probabilities of ER/hospital visits (type 1 patient, 24%, type 2 patient, 35%). Initial estimates of survival and adverse events associated with IP/IV chemotherapy differ among experts. The Delphi process works to build consensus and may be a pragmatic tool to inform patients of their expected outcomes. Copyright © 2015 Elsevier Inc. All rights reserved.

An optical chemical sensor for thorium (IV) determination based on thorin.

PubMed

Rastegarzadeh, S; Pourreza, N; Saeedi, I

2010-01-15

A selective method for the determination of thorium (IV) using an optical sensor is described. The sensing membrane is prepared by immobilization of thorin-methyltrioctylammonium ion pair on triacetylcellulose polymer. The sensor produced a linear response for thorium (IV) concentration in the range of 6.46 x 10(-6) to 9.91 x 10(-5)mol L(-1) with detection limit of 1.85 x 10(-6)mol L(-1). The regeneration of optode was accomplished completely at a short time (less than 20s) with 0.1 mol L(-1) of oxalate ion solution. The relative standard deviation for ten replicate measurements of 2.15 x 10(-5) and 8.62 x 10(-5)mol L(-1) of thorium was 2.71 and 1.65%, respectively. The optode membrane exhibits good selectivity for thorium (IV) over several other ionic species and are comparable to those obtained in case of spectrophotometric determination of thorium using thorin in solution. A good agreement with the ICP-MS and spiked method was achieved when the proposed optode was applied to the determination of thorium (IV) in dust and water samples.

Determination of sulphite in wine by coulometric titration.

PubMed

Lowinsohn, D; Bertotti, M

2001-09-01

A method for the determination of both free and bound S(IV) in white wine samples by coulometric titration with electrogenerated iodine is described, the S(IV) speciation being performed by extracting SO2 from samples acidified wiith hydrochloric acid. Titrations of samples treated with NaOH led to the total S(IV) concentration, the results being in agreement with the ones obtained by the distillation procedure as well as by using the classical Monier-Williams method. An average recovery of 97% was obtained for samples spiked with S(IV) in the range 0.4-1.2 mM, which demonstrated the validity of the proposed procedure. The repeatability was 1.3% and the limit of detection was estimated as 0.01 mM. Results from direct titrations of wine added to the electrochemical cell are reported, which give indications of the stability of adducts towards the reaction with iodine.

Multivariate Analysis for Quantification of Plutonium(IV) in Nitric Acid Based on Absorption Spectra

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

Lines, Amanda M.; Adami, Susan R.; Sinkov, Sergey I.

Development of more effective, reliable, and fast methods for monitoring process streams is a growing opportunity for analytical applications. Many fields can benefit from on-line monitoring, including the nuclear fuel cycle where improved methods for monitoring radioactive materials will facilitate maintenance of proper safeguards and ensure safe and efficient processing of materials. On-line process monitoring with a focus on optical spectroscopy can provide a fast, non-destructive method for monitoring chemical species. However, identification and quantification of species can be hindered by the complexity of the solutions if bands overlap or show condition-dependent spectral features. Plutonium (IV) is one example ofmore » a species which displays significant spectral variation with changing nitric acid concentration. Single variate analysis (i.e. Beer’s Law) is difficult to apply to the quantification of Pu(IV) unless the nitric acid concentration is known and separate calibration curves have been made for all possible acid strengths. Multivariate, or chemometric, analysis is an approach that allows for the accurate quantification of Pu(IV) without a priori knowledge of nitric acid concentration.« less

Predicting DPP-IV inhibitors with machine learning approaches

NASA Astrophysics Data System (ADS)

Cai, Jie; Li, Chanjuan; Liu, Zhihong; Du, Jiewen; Ye, Jiming; Gu, Qiong; Xu, Jun

2017-04-01

Dipeptidyl peptidase IV (DPP-IV) is a promising Type 2 diabetes mellitus (T2DM) drug target. DPP-IV inhibitors prolong the action of glucagon-like peptide-1 (GLP-1) and gastric inhibitory peptide (GIP), improve glucose homeostasis without weight gain, edema, and hypoglycemia. However, the marketed DPP-IV inhibitors have adverse effects such as nasopharyngitis, headache, nausea, hypersensitivity, skin reactions and pancreatitis. Therefore, it is still expected for novel DPP-IV inhibitors with minimal adverse effects. The scaffolds of existing DPP-IV inhibitors are structurally diversified. This makes it difficult to build virtual screening models based upon the known DPP-IV inhibitor libraries using conventional QSAR approaches. In this paper, we report a new strategy to predict DPP-IV inhibitors with machine learning approaches involving naïve Bayesian (NB) and recursive partitioning (RP) methods. We built 247 machine learning models based on 1307 known DPP-IV inhibitors with optimized molecular properties and topological fingerprints as descriptors. The overall predictive accuracies of the optimized models were greater than 80%. An external test set, composed of 65 recently reported compounds, was employed to validate the optimized models. The results demonstrated that both NB and RP models have a good predictive ability based on different combinations of descriptors. Twenty "good" and twenty "bad" structural fragments for DPP-IV inhibitors can also be derived from these models for inspiring the new DPP-IV inhibitor scaffold design.

Tumor Response and Apoptosis of N1-S1 Rodent Hepatomas in Response to Intra-arterial and Intravenous Benzamide Riboside

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

McLennan, Gordon, E-mail: gmclenna@me.com; Bennett, Stacy L.; Ju, Shenghong

2012-06-15

Purpose: Benzamide riboside (BR) induces tumor apoptosis in multiple cell lines and animals. This pilot study compares apoptosis and tumor response in rat hepatomas treated with hepatic arterial BR (IA) or intravenous (IV) BR. Methods: A total of 10{sup 6} N1-S1 cells were placed in the left hepatic lobes of 15 Sprague-Dawley rats. After 2 weeks, BR (20 mg/kg) was infused IA (n = 5) or IV (n = 5). One animal in each group was excluded for technical factors, which prevented a full dose administration (1 IA and 1 IV). Five rats received saline (3 IA and 2 IV).more » Animals were killed after 3 weeks. Tumor volumes after IA and IV treatments were analyzed by Wilcoxon rank sum test. The percentage of tumor and normal liver apoptosis was counted by using 10 fields of TUNEL (terminal deoxynucleotidyl transferase dUTP nick-end labeling)-stained slides at 40 Multiplication-Sign magnification. The percentage of apoptosis was compared between IV and IA administrations and with saline sham-treated rats by the Wilcoxon rank sum test. Results: Tumors were smaller after IA treatment, but this did not reach statistical significance (0.14 IA vs. 0.57 IV; P = 0.138). There was much variability in percentage of apoptosis and no significant difference between IA and IV BR (44.49 vs. 1.52%; P = 0.18); IA BR and saline (44.49 vs. 33.83%; P = 0.66); or IV BR and saline (1.52 vs. 193%; P = 0.18). Conclusions: Although differences in tumor volumes did not reach statistical significance, there was a trend toward smaller tumors after IA BR than IV BR in this small pilot study. Comparisons of these treatment methods will require a larger sample size and repeat experimentation.« less

Intravenous Solutions for Exploration Missions

NASA Technical Reports Server (NTRS)

Miller, Fletcher J.; Niederhaus, Charles; Barlow, Karen; Griffin, DeVon

2007-01-01

This paper describes the intravenous (IV) fluids requirements being developed for medical care during NASA s future exploration class missions. Previous research on IV solution generation and mixing in space is summarized. The current exploration baseline mission profiles are introduced, potential medical conditions described and evaluated for fluidic needs, and operational issues assessed. We briefly introduce potential methods for generating IV fluids in microgravity. Conclusions on the recommended fluid volume requirements are presented.

PaCeQuant: A Tool for High-Throughput Quantification of Pavement Cell Shape Characteristics1[OPEN

PubMed Central

Poeschl, Yvonne; Plötner, Romina

2017-01-01

Pavement cells (PCs) are the most frequently occurring cell type in the leaf epidermis and play important roles in leaf growth and function. In many plant species, PCs form highly complex jigsaw-puzzle-shaped cells with interlocking lobes. Understanding of their development is of high interest for plant science research because of their importance for leaf growth and hence for plant fitness and crop yield. Studies of PC development, however, are limited, because robust methods are lacking that enable automatic segmentation and quantification of PC shape parameters suitable to reflect their cellular complexity. Here, we present our new ImageJ-based tool, PaCeQuant, which provides a fully automatic image analysis workflow for PC shape quantification. PaCeQuant automatically detects cell boundaries of PCs from confocal input images and enables manual correction of automatic segmentation results or direct import of manually segmented cells. PaCeQuant simultaneously extracts 27 shape features that include global, contour-based, skeleton-based, and PC-specific object descriptors. In addition, we included a method for classification and analysis of lobes at two-cell junctions and three-cell junctions, respectively. We provide an R script for graphical visualization and statistical analysis. We validated PaCeQuant by extensive comparative analysis to manual segmentation and existing quantification tools and demonstrated its usability to analyze PC shape characteristics during development and between different genotypes. PaCeQuant thus provides a platform for robust, efficient, and reproducible quantitative analysis of PC shape characteristics that can easily be applied to study PC development in large data sets. PMID:28931626

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

Liu, Xiu-Li, E-mail: usually.158@163.com; Hubei Key Laboratory of Tumor Biological Behaviors and Hubei Cancer Clinical Study Center, No 169 Donghu Road, Wuchang District, Wuhan 430071; Peng, Chun-Wei, E-mail: pqc278@163.com

Highlights: {yields} HER2 level is closely related to the biologic behaviors of breast cancer cells. {yields} A new method to simultaneously image HER2 and type IV collagen was established. {yields} HER2 status and type IV collagen degradation predict breast cancer invasion. {yields} The complex interactions between tumor and its environment were revealed. -- Abstract: It has been well recognized that human epidermal growth factor receptor 2 (HER2) level in breast cancer (BC) is closely related to the malignant biologic behaviors of the tumor, including invasion and metastasis. Yet, there has been a lack of directly observable evidence to support suchmore » notion. Here we report a quantum dots (QDs)-based double-color imaging technique to simultaneously show the HER2 level on BC cells and the type IV collagen in the tumor matrix. In benign breast tumor, the type IV collagen was intact. With the increasing of HER2 expression level, there has been a progressive decrease in type IV collagen around the cancer nest. At HER2 (3+) expression level, there has virtually been a total destruction of type IV collagen. Moreover, HER2 (3+) BC cells also show direct invasion into the blood vessels. This novel imaging method provides direct observable evidence to support the theory that the HER2 expression level is directly related to BC invasion.« less

Characterization of cardiac quiescence from retrospective cardiac computed tomography using a correlation-based phase-to-phase deviation measure

PubMed Central

Wick, Carson A.; McClellan, James H.; Arepalli, Chesnal D.; Auffermann, William F.; Henry, Travis S.; Khosa, Faisal; Coy, Adam M.; Tridandapani, Srini

2015-01-01

Purpose: Accurate knowledge of cardiac quiescence is crucial to the performance of many cardiac imaging modalities, including computed tomography coronary angiography (CTCA). To accurately quantify quiescence, a method for detecting the quiescent periods of the heart from retrospective cardiac computed tomography (CT) using a correlation-based, phase-to-phase deviation measure was developed. Methods: Retrospective cardiac CT data were obtained from 20 patients (11 male, 9 female, 33–74 yr) and the left main, left anterior descending, left circumflex, right coronary artery (RCA), and interventricular septum (IVS) were segmented for each phase using a semiautomated technique. Cardiac motion of individual coronary vessels as well as the IVS was calculated using phase-to-phase deviation. As an easily identifiable feature, the IVS was analyzed to assess how well it predicts vessel quiescence. Finally, the diagnostic quality of the reconstructed volumes from the quiescent phases determined using the deviation measure from the vessels in aggregate and the IVS was compared to that from quiescent phases calculated by the CT scanner. Three board-certified radiologists, fellowship-trained in cardiothoracic imaging, graded the diagnostic quality of the reconstructions using a Likert response format: 1 = excellent, 2 = good, 3 = adequate, 4 = nondiagnostic. Results: Systolic and diastolic quiescent periods were identified for each subject from the vessel motion calculated using the phase-to-phase deviation measure. The motion of the IVS was found to be similar to the aggregate vessel (AGG) motion. The diagnostic quality of the coronary vessels for the quiescent phases calculated from the aggregate vessel (PAGG) and IVS (PIV S) deviation signal using the proposed methods was comparable to the quiescent phases calculated by the CT scanner (PCT). The one exception was the RCA, which improved for PAGG for 18 of the 20 subjects when compared to PCT (PCT = 2.48; PAGG = 2.07, p = 0.001). Conclusions: A method for quantifying the motion of specific coronary vessels using a correlation-based, phase-to-phase deviation measure was developed and tested on 20 patients receiving cardiac CT exams. The IVS was found to be a suitable predictor of vessel quiescence. The diagnostic quality of the quiescent phases detected by the proposed methods was comparable to those calculated by the CT scanner. The ability to quantify coronary vessel quiescence from the motion of the IVS can be used to develop new CTCA gating techniques and quantify the resulting potential improvement in CTCA image quality. PMID:25652511

Chemometric methods for the simultaneous determination of some water-soluble vitamins.

PubMed

Mohamed, Abdel-Maaboud I; Mohamed, Horria A; Mohamed, Niveen A; El-Zahery, Marwa R

2011-01-01

Two spectrophotometric methods, derivative and multivariate methods, were applied for the determination of binary, ternary, and quaternary mixtures of the water-soluble vitamins thiamine HCI (I), pyridoxine HCI (II), riboflavin (III), and cyanocobalamin (IV). The first method is divided into first derivative and first derivative of ratio spectra methods, and the second into classical least squares and principal components regression methods. Both methods are based on spectrophotometric measurements of the studied vitamins in 0.1 M HCl solution in the range of 200-500 nm for all components. The linear calibration curves were obtained from 2.5-90 microg/mL, and the correlation coefficients ranged from 0.9991 to 0.9999. These methods were applied for the analysis of the following mixtures: (I) and (II); (I), (II), and (III); (I), (II), and (IV); and (I), (II), (III), and (IV). The described methods were successfully applied for the determination of vitamin combinations in synthetic mixtures and dosage forms from different manufacturers. The recovery ranged from 96.1 +/- 1.2 to 101.2 +/- 1.0% for derivative methods and 97.0 +/- 0.5 to 101.9 +/- 1.3% for multivariate methods. The results of the developed methods were compared with those of reported methods, and gave good accuracy and precision.

A proposed method to estimate premorbid full scale intelligence quotient (FSIQ) for the Canadian Wechsler Intelligence Scale for Children-Fourth Edition (WISC-IV) using demographic and combined estimation procedures.

PubMed

Schoenberg, Mike R; Lange, Rael T; Saklofske, Donald H

2007-11-01

Establishing a comparison standard in neuropsychological assessment is crucial to determining change in function. There is no available method to estimate premorbid intellectual functioning for the Wechsler Intelligence Scale for Children-Fourth Edition (WISC-IV). The WISC-IV provided normative data for both American and Canadian children aged 6 to 16 years old. This study developed regression algorithms as a proposed method to estimate full-scale intelligence quotient (FSIQ) for the Canadian WISC-IV. Participants were the Canadian WISC-IV standardization sample (n = 1,100). The sample was randomly divided into two groups (development and validation groups). The development group was used to generate regression algorithms; 1 algorithm only included demographics, and 11 combined demographic variables with WISC-IV subtest raw scores. The algorithms accounted for 18% to 70% of the variance in FSIQ (standard error of estimate, SEE = 8.6 to 14.2). Estimated FSIQ significantly correlated with actual FSIQ (r = .30 to .80), and the majority of individual FSIQ estimates were within +/-10 points of actual FSIQ. The demographic-only algorithm was less accurate than algorithms combining demographic variables with subtest raw scores. The current algorithms yielded accurate estimates of current FSIQ for Canadian individuals aged 6-16 years old. The potential application of the algorithms to estimate premorbid FSIQ is reviewed. While promising, clinical validation of the algorithms in a sample of children and/or adolescents with known neurological dysfunction is needed to establish these algorithms as a premorbid estimation procedure.

Intravenous catheter training system: computer-based education versus traditional learning methods.

PubMed

Engum, Scott A; Jeffries, Pamela; Fisher, Lisa

2003-07-01

Virtual reality simulators allow trainees to practice techniques without consequences, reduce potential risk associated with training, minimize animal use, and help to develop standards and optimize procedures. Current intravenous (IV) catheter placement training methods utilize plastic arms, however, the lack of variability can diminish the educational stimulus for the student. This study compares the effectiveness of an interactive, multimedia, virtual reality computer IV catheter simulator with a traditional laboratory experience of teaching IV venipuncture skills to both nursing and medical students. A randomized, pretest-posttest experimental design was employed. A total of 163 participants, 70 baccalaureate nursing students and 93 third-year medical students beginning their fundamental skills training were recruited. The students ranged in age from 20 to 55 years (mean 25). Fifty-eight percent were female and 68% percent perceived themselves as having average computer skills (25% declaring excellence). The methods of IV catheter education compared included a traditional method of instruction involving a scripted self-study module which involved a 10-minute videotape, instructor demonstration, and hands-on-experience using plastic mannequin arms. The second method involved an interactive multimedia, commercially made computer catheter simulator program utilizing virtual reality (CathSim). The pretest scores were similar between the computer and the traditional laboratory group. There was a significant improvement in cognitive gains, student satisfaction, and documentation of the procedure with the traditional laboratory group compared with the computer catheter simulator group. Both groups were similar in their ability to demonstrate the skill correctly. CONCLUSIONS; This evaluation and assessment was an initial effort to assess new teaching methodologies related to intravenous catheter placement and their effects on student learning outcomes and behaviors. Technology alone is not a solution for stand alone IV catheter placement education. A traditional learning method was preferred by students. The combination of these two methods of education may further enhance the trainee's satisfaction and skill acquisition level.

Coverage and parental perceptions of influenza vaccination among parents of children aged 6 to 23 months in Hong Kong

PubMed Central

2013-01-01

Background The impact of influenza on young children can be severe and even fatal. Influenza vaccination (IV) has been shown to be effective in reducing complications of influenza among children. This study investigated the prevalence and factors of IV among children aged 6-23 months in Hong Kong. Methods A sample of 401 Chinese parents of children aged 6-23 months were interviewed at local Maternal and Child Health Centers. Socio-demographic information, variables related to Health Belief Model, including perceptions about the child’s chance of contracting influenza, perceived harm of influenza on children, perceived benefits and side-effects of IV, having received recommendations from health professionals to uptake IV, and IV behaviors of the children were measured. Multivariate analysis was used to examine factors associated with IV behaviors of children. Results Only 9% of the children had ever been vaccinated. Among those parents who had heard of IV (92.0%), substantial proportions perceived that IV could reduce the risk of influenza-induced complications (70.5%), hospitalization (70.5%) and death (65.9%). Relatively few of the participants believed that IV had no side effects (17.1%) and even less had been recommended by health care professionals to uptake IV (10.6%). Results from multivariate analysis showed that physician recommendations were associated with a higher likelihood for IV among younger children, whilst parental perceptions of the side effects of IV was associated with a lower likelihood for IV. Conclusion The prevalence of IV among children aged 6-23 months in Hong Kong was very low. Promotion of IV with the component of physician recommendations and parents’ knowledge about IV safety for this group is warranted. PMID:24171947

Effect of oxidation state and ionic strength on sorption of actinides (Th, U, Np, Am) to geologic media [Abstract and References Only

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

Dittrich, Timothy M.; Richmann, Michael K.; Reed, Donald T.

2015-10-30

The degree of conservatism in the estimated sorption partition coefficients (K ds) used in a performance assessment model is being evaluated based on a complementary batch and column method. The main focus of this work is to investigate the role of ionic strength, solution chemistry, and oxidation state (III-VI) in actinide sorption to dolomite rock. Based on redox conditions and solution chemistry expected at the WIPP, possible actinide species include Pu(III), Pu(IV), U(IV), U(VI), Np(IV), Np(V), Am(III), and Th(IV).

Chromogenic Detection of Dipeptidyl Peptidase IV (DPP-IV) Activity using Peptide-Functionalized Gold Nanoparticles

NASA Astrophysics Data System (ADS)

Abul-Huda, Yasin Mohammad

Metal nanoparticles offer a useful platform for a wide range of biological applications especially for biosensing, bioimaging and drug delivery. This thesis presents a body of original research describing the synthesis, characterisation and development of a novel and convenient biosensing assay for detection of dipeptidyl peptidase IV (DPP-IV) enzyme activity using peptide functionalized gold nanoparticles. The distinctive optical and physical properties of gold nanoparticles (Au NP) were harnessed for the development of a colorimetric assay for rapid sensing of DPP-IV activities and screening DPP-IV inhbitors. The citrate reduction method for Au NPs synthesis was optimised and several potential peptide substrates (GPDC, VP-EN-DC, C/G dipeptide, GPG-EN-PEG4-LA, GPDCALNNC) were designed to provide substrates that mimic the DPP-IV natural substrates. The performances of the substrate functionalized Au NPs were assessed for their appropriateness for the detection of the enzyme activity. Addition of DPP-IV to the solutions containing the functionalized Au NPs resulted in cleavage of the substrate and thus causing the aggregation of the Au NPs which in turn led to a shift of the surface plasmon peak toward longer wavelengths, and a change of the colour of the colloidal suspension from red to blue. Overall, real-time detection of DPP-IV activity over a broader range (0-40 U/L) with high selectivity and stability was obtained, thus providing a method that can be used to determine the levels of DPP-IV/CD26 in biological fluids such as serum and plasma. Further assay developments were conducted to overcome limitations encountered with the original Au NP assay, especially the narrow dynamic linear range and stability in high ionic strength solutions. Validation and comparison of the Au NP assay developed has revealed that this method is highly correlated to the gold standard chromogenic Gly-Pro-pNA method for detection of enzyme activity in biological samples. Very good recoveries (in the range 83.6 -114.9%) were obtained in spiked serum samples, which indicate that this assay could provide a suitable alternative for enzyme activity detection with the naked eye and without the need for sophisticated instruments. Investigations into the effects of incorporating different stabilizers in order to improve the stability of the peptide functionalized Au NP in high ionic strength solutions were also investigated. Gold nanoparticles have different shapes and structures and an alternative approach for detection of DPP-IV activity using gold nanorods due to their higher refractive index sensitivities was explored. As a conclusion, three out of five approaches, all utilising Au NP-ligand conjugates were demonstrated useful for the detection of the DPP-IV activity. The system developed here is portable and would permit on-site analysis of samples, which offers a real alternative approach from traditional assays and reduces the need for laboratory testing. The logical next step in this research would be the continuation of experiments to transform this test into a point of care testing device that could offer an early detection tool for disease management.

Effects of Vanadium Substitution on the Structure and Photocatalytic Behavior of ETS-10

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

Shough,A.; Doren, D.; Nash, M.

2007-01-01

A combination of experimental and computational methods has been used to investigate the effects of vanadium doping in ETS-10. Near edge X-ray absorption fine structure (NEXAFS) spectra reveal octahedrally coordinated V{sup IV} and V{sup V} species within V-doped ETS-10 materials, confirming substitution for Ti{sup IV} sites only. Computational models, using hybrid density functional theory/molecular mechanics (DFT/MM) methods, have been developed that contain varying concentrations of V{sup IV} and V{sup V} within the O-M-O (M = Ti, V) chain. Geometry optimizations indicate that V{sup V} substitution leads to larger changes in the local chain geometry than V{sup IV} substitution. Substitution energeticsmore » for V{sup IV} and V{sup V} in different sites have been calculated to determine preferred locations of the two species, suggesting that long chains of V{sup V} are not stable and demonstrating the need for both V{sup V} and V{sup IV} within V-substituted materials. Wavefunctions for systems with an electron added or removed are used to identify electron and hole trapping sites associated with the V{sup V} and V{sup IV} doping centers respectively. An increase in photocatalytic activity is predicted at low [V] due to improved charge separation. However photocatalytic activity is expected to decrease at high [V] due to increased carrier recombination. These results are consistent with recent experimental data.« less

The determination of uranium (IV) in apatite

USGS Publications Warehouse

Clarke, Roy S.; Altschuler, Zalman S.

1956-01-01

Geologic and mineralogic evidence indicate that the uranium present in apatite may proxy for calcium in the mineral structure as U(IV). An experimental investigation was conducted and chemical evidence was obtained that establishes the presence of U(IV) in apatite. The following analytical procedure was developed for the determination of U(IV). Carbonate-fluorapatite is dissolved in cold 1.5M orthophosphoric acid and fluorapatite is dissolved in cold 1.2M hydrochloric acid containing 1.5 g of hydroxylamine hydrochloride per 100 ml. Uranium (IV) is precipitated by cupferron using titanium as a carrier. The uranium in the precipitate is separated by use of the ethyl acetate extraction procedure and determined fluorimetrically. The validity and the limitations of the method have been established by spike experiments.

Intravenous Fluid Mixing in Normal Gravity, Partial Gravity, and Microgravity: Down-Selection of Mixing Methods

NASA Technical Reports Server (NTRS)

Niederhaus, Charles E.; Miller, Fletcher J.

2008-01-01

The missions envisioned under the Vision for Space Exploration will require development of new methods to handle crew medical care. Medications and intravenous (IV) fluids have been identified as one area needing development. Storing certain medications and solutions as powders or concentrates can both increase the shelf life and reduce the overall mass and volume of medical supplies. The powders or concentrates would then be mixed in an IV bag with Sterile Water for Injection produced in situ from the potable water supply. Fluid handling in microgravity is different than terrestrial settings, and requires special consideration in the design of equipment. This document describes the analyses and down-select activities used to identify the IV mixing method to be developed that is suitable for ISS and exploration missions. The chosen method is compatible with both normal gravity and microgravity, maintains sterility of the solution, and has low mass and power requirements. The method will undergo further development, including reduced gravity aircraft experiments and computations, in order to fully develop the mixing method and associated operational parameters.

Effect of impurities and processing on silicon solar cells. Volume 1: Characterization methods for impurities in silicon and impurity effects data base

NASA Technical Reports Server (NTRS)

Hopkins, R. H.; Davis, J. R.; Rohatgi, A.; Campbell, R. B.; Blais, P. D.; Rai-Choudhury, P.; Stapleton, R. E.; Mollenkopf, H. C.; Mccormick, J. R.

1980-01-01

Two major topics are treated: methods to measure and evaluate impurity effects in silicon and comprehensive tabulations of data derived during the study. Discussions of deep level spectroscopy, detailed dark I-V measurements, recombination lifetime determination, scanned laser photo-response, conventional solar cell I-V techniques, and descriptions of silicon chemical analysis are presented and discussed. The tabulated data include lists of impurity segregation coefficients, ingot impurity analyses and estimated concentrations, typical deep level impurity spectra, photoconductive and open circuit decay lifetimes for individual metal-doped ingots, and a complete tabulation of the cell I-V characteristics of nearly 200 ingots.

Determination of thorium (IV) using isophthalaldehyde-tetrapyrrole as probe by resonance light scattering, second-order scattering and frequency-doubling scattering spectra

NASA Astrophysics Data System (ADS)

Wang, Jiao; Xue, Jinhua; Xiao, Xilin; Xu, Li; Jiang, Min; Peng, Pengcheng; Liao, Lifu

2017-12-01

The coordination reaction of thorium (IV) with a ditopic bidentate ligand to form supramolecular polymer was studied by resonance light scattering (RLS) spectra, second-order scattering (SOS) spectra and frequency-doubling scattering (FDS) spectra, respectively. The ditopic bidentate ligand is isophthalaldehyde-tetrapyrrole (IPTP). It was synthesized through a condensation reaction of isophthalaldehyde with pyrrole. The formation of supramolecular polymer results in remarkable intensity enhancements of the three light scattering signals. The maximum scattering wavelengths of RLS, FDS and SOS were 290, 568 and 340 nm, respectively. The reaction was used to establish new light scattering methods for the determination of thorium (IV) by using IPTP as probe. Under optimum conditions, the intensity enhancements of RLS, SOS and FDS were directly proportional to the concentration of thorium (IV) in the ranges of 0.01 to 1.2 μg mL- 1, 0.05 to 1.2 μg mL- 1 and 0.05 to 1.2 μg mL- 1, respectively. The detection limits were 0.003 μg mL- 1, 0.012 μg mL- 1 and 0.021 μg mL- 1, respectively. The methods were suitable for analyzing thorium (IV) in actual samples. The results show acceptable recoveries and precision compared with a reference method.

Determination of total antioxidant capacity by a new spectrofluorometric method based on Ce(IV) reduction: Ce(III) fluorescence probe for CERAC assay.

PubMed

Ozyurt, Dilek; Demirata, Birsen; Apak, Resat

2011-11-01

A Ce(IV)-based reducing capacity (CERAC) assay was developed to measure the total antioxidant capacity (TAC) of foods, in which Ce(IV) would selectively oxidize antioxidant compounds but not citric acid and reducing sugars which are not classified as antioxidants. The method is based on the electron-transfer (ET) reaction between Ce(IV) ion and antioxidants in optimized acidic sulphate medium (i.e., 0.3 M H(2)SO(4) and 0.7 M Na(2)SO(4)) and subsequent determination of the produced Ce(III) ions by a fluorometric method. The fluorescent product, Ce(III), exhibited strong fluorescence at 360 nm with an excitation wavelength of 256 nm, the fluorescence intensity being correlated to antioxidant power of the original sample. The linear concentration range for most antioxidants was quite wide, e.g., 5.0 × 10(-7)-1.0 × 10(-5) M for quercetin. The developed procedure was successfully applied to the TAC assay of antioxidant compounds such as trolox, quercetin, gallic acid, ascorbic acid, catechin, naringin, naringenin, caffeic acid, ferulic acid, glutathione, and cysteine. The proposed method was reproducible, additive in terms of TAC values of constituents of complex mixtures, and the trolox equivalent antioxidant capacities (TEAC coefficients) of the tested antioxidant compounds gave good correlations with those found by reference methods such as ABTS and CUPRAC.

Mono- and di-bromo platinum(IV) prodrugs via oxidative bromination: synthesis, characterization, and cytotoxicity.

PubMed

Xu, Zoufeng; Wang, Zhigang; Yiu, Shek-Man; Zhu, Guangyu

2015-12-14

Platinum(IV)-based anticancer prodrugs have attracted much attention due to their relative inertness under physiological conditions, being activated inside cells, and their capacity for functionalization with a variety of small-molecule or macromolecule moieties. Novel asymmetric platinum(IV) compounds synthesized through expedient and unique methods are desired. Here we utilize N-bromosuccinimide (NBS) and carry out oxidative bromination on platinum(II) drugs, namely cisplatin, carboplatin, and oxaliplatin, to obtain asymmetric and mono-bromo platinum(IV) prodrugs. Different solvents are used to obtain various compounds, and the compounds are further functionalized. Di-bromo compounds are also obtained through NBS-directed oxidative bromination in ethanol. The crystal structures of representative compounds are discussed, and the reduction potentials of some compounds are examined. A cytotoxicity test shows that the mono- and di-bromo platinum(IV) compounds are active against human ovarian cancer cells. Our study enriches the family of asymmetric platinum(IV) prodrugs and provides with a convenient strategy to obtain brominated platinum(IV) complexes.

Equatorial Ligand Perturbations Influence the Reactivity of Manganese(IV)-Oxo Complexes.

PubMed

Massie, Allyssa A; Denler, Melissa C; Cardoso, Luísa Thiara; Walker, Ashlie N; Hossain, M Kamal; Day, Victor W; Nordlander, Ebbe; Jackson, Timothy A

2017-04-03

Manganese(IV)-oxo complexes are often invoked as intermediates in Mn-catalyzed C-H bond activation reactions. While many synthetic Mn IV -oxo species are mild oxidants, other members of this class can attack strong C-H bonds. The basis for these reactivity differences is not well understood. Here we describe a series of Mn IV -oxo complexes with N5 pentadentate ligands that modulate the equatorial ligand field of the Mn IV center, as assessed by electronic absorption, electron paramagnetic resonance, and Mn K-edge X-ray absorption methods. Kinetic experiments show dramatic rate variations in hydrogen-atom and oxygen-atom transfer reactions, with faster rates corresponding to weaker equatorial ligand fields. For these Mn IV -oxo complexes, the rate enhancements are correlated with both 1) the energy of a low-lying 4 E excited state, which has been postulated to be involved in a two-state reactivity model, and 2) the Mn III/IV reduction potentials. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

Titanium(IV) isopropoxide mediated synthesis of pyrimidin-4-ones.

PubMed

Ramanjulu, Joshi M; Demartino, Michael P; Lan, Yunfeng; Marquis, Robert

2010-05-21

A novel, one-step method for the synthesis of tri- and tetrasubstituted pyrimidin-4-ones is reported. This method involves a titanium(IV)-mediated cyclization involving two sequential condensations of primary and beta-ketoamides. The reaction is operationally facile, readily scalable, and offers rapid entry into differentially substituted pyrimidin-4-one scaffolds. The high functional group compatibility allows for substantial diversification in the products generated from this transformation.

Effects of an oil spill on the leaf anatomical characteristics of a beach plant (Terminalia catappa L.).

PubMed

Punwong, Paramita; Juprasong, Yotin; Traiperm, Paweena

2017-09-01

This study investigated the short-term impacts of an oil spill on the leaf anatomical structures of Terminalia catappa L. from crude oil leakage in Rayong province, Thailand, in 2013. Approximately 3 weeks after the oil spill, leaves of T. catappa were collected along the coastline of Rayong from one affected site, five adjacent sites, and a control site. Slides of the leaf epidermis were prepared by the peeling method, while leaf and petiole transverse sections were prepared by paraffin embedding. Cell walls of adaxial epidermal cell on leaves in the affected site were straight instead of the jigsaw shape found in leaves from the adjacent and control sites. In addition, the stomatal index of the abaxial leaf surface was significantly lower in the affected site. Leaf and petiole transverse sections collected from the affected site showed increased cuticle thickness, epidermal cell diameter on both sides, and palisade mesophyll thickness; in contrast, vessel diameter and spongy mesophyll thickness were reduced. These significant changes in the leaf anatomy of T. catappa correspond with previous research and demonstrate the negative effects of oil spill pollution on plants. The anatomical changes of T. catappa in response to crude oil pollution are discussed as a possible indicator of pollution and may be used in monitoring crude oil pollution.

JIGSAW-GEO (1.0): Locally Orthogonal Staggered Unstructured Grid Generation for General Circulation Modelling on the Sphere

NASA Technical Reports Server (NTRS)

Engwirda, Darren

2017-01-01

An algorithm for the generation of non-uniform, locally orthogonal staggered unstructured spheroidal grids is described. This technique is designed to generate very high-quality staggered VoronoiDelaunay meshes appropriate for general circulation modelling on the sphere, including applications to atmospheric simulation, ocean-modelling and numerical weather prediction. Using a recently developed Frontal-Delaunay refinement technique, a method for the construction of high-quality unstructured spheroidal Delaunay triangulations is introduced. A locally orthogonal polygonal grid, derived from the associated Voronoi diagram, is computed as the staggered dual. It is shown that use of the Frontal-Delaunay refinement technique allows for the generation of very high-quality unstructured triangulations, satisfying a priori bounds on element size and shape. Grid quality is further improved through the application of hill-climbing-type optimisation techniques. Overall, the algorithm is shown to produce grids with very high element quality and smooth grading characteristics, while imposing relatively low computational expense. A selection of uniform and non-uniform spheroidal grids appropriate for high-resolution, multi-scale general circulation modelling are presented. These grids are shown to satisfy the geometric constraints associated with contemporary unstructured C-grid-type finite-volume models, including the Model for Prediction Across Scales (MPAS-O). The use of user-defined mesh-spacing functions to generate smoothly graded, non-uniform grids for multi-resolution-type studies is discussed in detail.

JIGSAW-GEO (1.0): locally orthogonal staggered unstructured grid generation for general circulation modelling on the sphere

NASA Astrophysics Data System (ADS)

Engwirda, Darren

2017-06-01

An algorithm for the generation of non-uniform, locally orthogonal staggered unstructured spheroidal grids is described. This technique is designed to generate very high-quality staggered Voronoi-Delaunay meshes appropriate for general circulation modelling on the sphere, including applications to atmospheric simulation, ocean-modelling and numerical weather prediction. Using a recently developed Frontal-Delaunay refinement technique, a method for the construction of high-quality unstructured spheroidal Delaunay triangulations is introduced. A locally orthogonal polygonal grid, derived from the associated Voronoi diagram, is computed as the staggered dual. It is shown that use of the Frontal-Delaunay refinement technique allows for the generation of very high-quality unstructured triangulations, satisfying a priori bounds on element size and shape. Grid quality is further improved through the application of hill-climbing-type optimisation techniques. Overall, the algorithm is shown to produce grids with very high element quality and smooth grading characteristics, while imposing relatively low computational expense. A selection of uniform and non-uniform spheroidal grids appropriate for high-resolution, multi-scale general circulation modelling are presented. These grids are shown to satisfy the geometric constraints associated with contemporary unstructured C-grid-type finite-volume models, including the Model for Prediction Across Scales (MPAS-O). The use of user-defined mesh-spacing functions to generate smoothly graded, non-uniform grids for multi-resolution-type studies is discussed in detail.

Magic in the machine: a computational magician's assistant.

PubMed

Williams, Howard; McOwan, Peter W

2014-01-01

A human magician blends science, psychology, and performance to create a magical effect. In this paper we explore what can be achieved when that human intelligence is replaced or assisted by machine intelligence. Magical effects are all in some form based on hidden mathematical, scientific, or psychological principles; often the parameters controlling these underpinning techniques are hard for a magician to blend to maximize the magical effect required. The complexity is often caused by interacting and often conflicting physical and psychological constraints that need to be optimally balanced. Normally this tuning is done by trial and error, combined with human intuitions. Here we focus on applying Artificial Intelligence methods to the creation and optimization of magic tricks exploiting mathematical principles. We use experimentally derived data about particular perceptual and cognitive features, combined with a model of the underlying mathematical process to provide a psychologically valid metric to allow optimization of magical impact. In the paper we introduce our optimization methodology and describe how it can be flexibly applied to a range of different types of mathematics based tricks. We also provide two case studies as exemplars of the methodology at work: a magical jigsaw, and a mind reading card trick effect. We evaluate each trick created through testing in laboratory and public performances, and further demonstrate the real world efficacy of our approach for professional performers through sales of the tricks in a reputable magic shop in London.

A Cyber-Attack Detection Model Based on Multivariate Analyses

NASA Astrophysics Data System (ADS)

Sakai, Yuto; Rinsaka, Koichiro; Dohi, Tadashi

In the present paper, we propose a novel cyber-attack detection model based on two multivariate-analysis methods to the audit data observed on a host machine. The statistical techniques used here are the well-known Hayashi's quantification method IV and cluster analysis method. We quantify the observed qualitative audit event sequence via the quantification method IV, and collect similar audit event sequence in the same groups based on the cluster analysis. It is shown in simulation experiments that our model can improve the cyber-attack detection accuracy in some realistic cases where both normal and attack activities are intermingled.

Multiple Intravenous Infusions Phase 2a: Ontario Survey

PubMed Central

Fan, Mark; Koczmara, Christine; Masino, Caterina; Cassano-Piché, Andrea; Trbovich, Patricia; Easty, Anthony

2014-01-01

Background Research conducted in earlier phases of this study prospectively identified a number of concerns related to the safe administration of multiple intravenous (IV) infusions in Ontario hospitals. Objective To investigate the potential prevalence of practices or policies that may contribute to the patient safety risks identified in Phase 1b of this study. Data Sources and Review Methods Sixty-four survey responses were analyzed from clinical units where multiple IV infusions may occur (e.g., adult intensive care units). Survey questions were organized according to the topics identified in Phase 1b as potential contributors to patient harm (e.g., labelling practices, patient transfer practices, secondary infusion policies). Results Survey results indicated suboptimal practices and policies in some clinical units, and variability in a number of infusion practices. Key areas of concern included the following: use of primary IV tubing without back check valves when administering secondary infusions administration of secondary infusions with/as high-alert continuous IV medications potential confusion about how IV tubing should be labelled to reflect replacement date and time interruptions to IV therapy due to IV pump and/or tubing changes when patients are transferred between clinical units coadministration of continuous or intermittent infusions on central venous pressure monitoring ports variability in respondents’ awareness of the infusion pump's bolus capabilities Limitations Due to the limited sample size, survey responses may not be representative of infusion practices across Ontario. Answers to some questions indicated that the intent of the questions might have been misunderstood. Due to a design error, 1 question about bolus administration methods was not shown to as many respondents as appropriate. Conclusions The Ontario survey revealed variability in IV infusion practice across the province and potential opportunities to improve safety. PMID:26257837

[Ion chromatography of L-ascorbic acid, sulfite and thiosulfate using their postcolumn reactions with cerium (IV) and fluorescence detection of cerium (III)].

PubMed

Chen, Q; Hu, K; Miura, Y

1999-09-01

An ion chromatographic method was used to separate the species of L-ascorbic acid, sulfite and thiosulfate in their mixtures. This method is based on the separation of each anion in their mixtures by using a separation column, and then on the fluorimetric measurement of cerium (III) formed by a postcolumn reaction of cerium (IV) with the species of L-ascorbic acid, sulfite and thiosulfate in the effluent. The optimal conditions for separating and determining the above three species have been established. By using a 3 mmol/L carbonate eluent, the species of L-ascorbic acid, sulfite and thiosulfate could be eluted at the proper retention times of 1.7, 2.6 and 5.0 min, respectively, and these three anions could be separated completely. The effects of the concentrations of cerium (IV) and sulfuric acid in the postcolumn reaction solution on the chromatographic peak-height were tested in order to obtain the optimal peak-height. It was found that the peak-height at first increases rapidly with an increase in the concentration of cerium (IV) and sulfuric acid respectively up to a certain concertation, then increases slowly. These critical concentrations of cerium (IV) and sulfuric acid also depend on the amount of the analyte injected. Meanwhile the baseline signals of the sepectra increase with an increase in the concentration of cerium (IV). Some concentrations above the critical concentration of sulfuric acid could be selected as the optimal concentration of sulfuric acid, but the concentration of cerium (IV) should be optimized by establishing a compromise between the higher peak-height and the lower baseline signal. The detection limit of this method was found to be 1 mumol/L for thiosulfate when an amount of 100 microL analyte was injected.

Overcoming the brittleness of glass through bio-inspiration and micro-architecture.

PubMed

Mirkhalaf, M; Dastjerdi, A Khayer; Barthelat, F

2014-01-01

Highly mineralized natural materials such as teeth or mollusk shells boast unusual combinations of stiffness, strength and toughness currently unmatched by engineering materials. While high mineral contents provide stiffness and hardness, these materials also contain weaker interfaces with intricate architectures, which can channel propagating cracks into toughening configurations. Here we report the implementation of these features into glass, using a laser engraving technique. Three-dimensional arrays of laser-generated microcracks can deflect and guide larger incoming cracks, following the concept of 'stamp holes'. Jigsaw-like interfaces, infiltrated with polyurethane, furthermore channel cracks into interlocking configurations and pullout mechanisms, significantly enhancing energy dissipation and toughness. Compared with standard glass, which has no microstructure and is brittle, our bio-inspired glass displays built-in mechanisms that make it more deformable and 200 times tougher. This bio-inspired approach, based on carefully architectured interfaces, provides a new pathway to toughening glasses, ceramics or other hard and brittle materials.

Quantity of Movement as a Measure of Engagement for Dementia: The Influence of Motivational Disorders

PubMed Central

Perugia, Giulia; Rodríguez-Martín, Daniel; Boladeras, Marta Díaz; Mallofré, Andreu Català; Barakova, Emilia; Rauterberg, Matthias

2017-01-01

Engagement in activities is crucial to improve quality of life in dementia. Yet, its measurement relies exclusively on behavior observation and the influence that behavioral and psychological symptoms of dementia (BPSD) have on it is overlooked. This study investigated whether quantity of movement, gauged with a wrist-worn accelerometer, could be a sound measure of engagement and whether apathy and depression negatively affected engagement. Fourteen participants with dementia took part in 6 sessions of activities: 3 of cognitive games (eg, jigsaw puzzles) and 3 of robot play (Pleo). Results highlighted significant correlations between quantity of movement and observational scales of engagement and a strong negative influence of apathy and depression on engagement. Overall, these findings suggest that quantity of movement could be used as an ancillary measure of engagement and underline the need to profile people with dementia according to their concurrent BPSD to better understand their engagement in activities. PMID:29148293

The history of ergot of rye (Claviceps purpurea) I: from antiquity to 1900.

PubMed

Lee, M R

2009-06-01

This article outlines the history of ergot of rye up to 1900. Ergot is a fungal disease that affects many grasses but is particularly damaging to rye. It occurs as the result of an infection by the parasitic organism Claviceps purpurea, which produces characteristic black spurs on the grass. When incorporated into grain, the ergot fungus can cause severe outbreaks of poisoning in humans called ergotism. There are two main clinical forms of toxicity, gangrenous and convulsive, where coma and death often supervene: the death rate for ergotism has been reported to be between 10 and 20 per cent in major outbreaks. Historical accounts note that ergot could accelerate labour, stop postpartum haemorrhage and inhibit lactation. At the end of the nineteenth century ergot was still regarded as a 'glorious chemical mess', but help would arrive in the early 1900s and the complex jigsaw would be solved.

Overcoming the brittleness of glass through bio-inspiration and micro-architecture

NASA Astrophysics Data System (ADS)

Mirkhalaf, M.; Dastjerdi, A. Khayer; Barthelat, F.

2014-01-01

Highly mineralized natural materials such as teeth or mollusk shells boast unusual combinations of stiffness, strength and toughness currently unmatched by engineering materials. While high mineral contents provide stiffness and hardness, these materials also contain weaker interfaces with intricate architectures, which can channel propagating cracks into toughening configurations. Here we report the implementation of these features into glass, using a laser engraving technique. Three-dimensional arrays of laser-generated microcracks can deflect and guide larger incoming cracks, following the concept of ‘stamp holes’. Jigsaw-like interfaces, infiltrated with polyurethane, furthermore channel cracks into interlocking configurations and pullout mechanisms, significantly enhancing energy dissipation and toughness. Compared with standard glass, which has no microstructure and is brittle, our bio-inspired glass displays built-in mechanisms that make it more deformable and 200 times tougher. This bio-inspired approach, based on carefully architectured interfaces, provides a new pathway to toughening glasses, ceramics or other hard and brittle materials.

Combining computational analyses and interactive visualization for document exploration and sensemaking in jigsaw.

PubMed

Görg, Carsten; Liu, Zhicheng; Kihm, Jaeyeon; Choo, Jaegul; Park, Haesun; Stasko, John

2013-10-01

Investigators across many disciplines and organizations must sift through large collections of text documents to understand and piece together information. Whether they are fighting crime, curing diseases, deciding what car to buy, or researching a new field, inevitably investigators will encounter text documents. Taking a visual analytics approach, we integrate multiple text analysis algorithms with a suite of interactive visualizations to provide a flexible and powerful environment that allows analysts to explore collections of documents while sensemaking. Our particular focus is on the process of integrating automated analyses with interactive visualizations in a smooth and fluid manner. We illustrate this integration through two example scenarios: an academic researcher examining InfoVis and VAST conference papers and a consumer exploring car reviews while pondering a purchase decision. Finally, we provide lessons learned toward the design and implementation of visual analytics systems for document exploration and understanding.

Quantitative analysis of microtubule orientation in interdigitated leaf pavement cells

PubMed Central

Akita, Kae; Higaki, Takumi; Kutsuna, Natsumaro; Hasezawa, Seiichiro

2015-01-01

Leaf pavement cells are shaped like a jigsaw puzzle in most dicotyledon species. Molecular genetic studies have identified several genes required for pavement cells morphogenesis and proposed that microtubules play crucial roles in the interdigitation of pavement cells. In this study, we performed quantitative analysis of cortical microtubule orientation in leaf pavement cells in Arabidopsis thaliana. We captured confocal images of cortical microtubules in cotyledon leaf epidermis expressing GFP-tubulinβ and quantitatively evaluated the microtubule orientations relative to the pavement cell growth axis using original image processing techniques. Our results showed that microtubules kept parallel orientations to the growth axis during pavement cell growth. In addition, we showed that immersion treatment of seed cotyledons in solutions containing tubulin polymerization and depolymerization inhibitors decreased pavement cell complexity. Treatment with oryzalin and colchicine inhibited the symmetric division of guard mother cells. PMID:26039484

Mechanochemical Polarization of Contiguous Cell Walls Shapes Plant Pavement Cells.

PubMed

Majda, Mateusz; Grones, Peter; Sintorn, Ida-Maria; Vain, Thomas; Milani, Pascale; Krupinski, Pawel; Zagórska-Marek, Beata; Viotti, Corrado; Jönsson, Henrik; Mellerowicz, Ewa J; Hamant, Olivier; Robert, Stéphanie

2017-11-06

The epidermis of aerial plant organs is thought to be limiting for growth, because it acts as a continuous load-bearing layer, resisting tension. Leaf epidermis contains jigsaw puzzle piece-shaped pavement cells whose shape has been proposed to be a result of subcellular variations in expansion rate that induce local buckling events. Paradoxically, such local compressive buckling should not occur given the tensile stresses across the epidermis. Using computational modeling, we show that the simplest scenario to explain pavement cell shapes within an epidermis under tension must involve mechanical wall heterogeneities across and along the anticlinal pavement cell walls between adjacent cells. Combining genetics, atomic force microscopy, and immunolabeling, we demonstrate that contiguous cell walls indeed exhibit hybrid mechanochemical properties. Such biochemical wall heterogeneities precede wall bending. Altogether, this provides a possible mechanism for the generation of complex plant cell shapes. Copyright © 2017 Elsevier Inc. All rights reserved.

New analytical methodology for analysing S(IV) species at low pH solutions by one stage titration method (bichromatometry) with a clear colour change. Could potentially replace the state-of-art-method iodometry at low pH analysis due higher accuracy

PubMed Central

Galfi, Istvan; Virtanen, Jorma; Gasik, Michael M.

2017-01-01

A new, faster and more reliable analytical methodology for S(IV) species analysis at low pH solutions by bichromatometry is proposed. For decades the state of the art methodology has been iodometry that is still well justified method for neutral solutions, thus at low pH media possess various side reactions increasing inaccuracy. In contrast, the new methodology has no side reactions at low pH media, requires only one titration step and provides a clear color change if S(IV) species are present in the solution. The method is validated using model solutions with known concentrations and applied to analyses of gaseous SO2 from purged solution in low pH media samples. The results indicate that bichromatometry can accurately analyze SO2 from liquid samples having pH even below 0 relevant to metallurgical industrial processes. PMID:29145479

A New Method to Assess Asymmetry in Fingerprints Could Be Used as an Early Indicator of Type 2 Diabetes Mellitus

PubMed Central

Morris, Molly R.; Ludwar, Bjoern Ch.; Swingle, Evan; Mamo, Mahelet N.; Shubrook, Jay H.

2016-01-01

Background: Inexpensive screening tools are needed to identify individuals predisposed to developing diabetes mellitus (DM). Such early identification coupled with an effective intervention could help many people avoid the substantial health costs of this disease. We investigated the hypothesis that fluctuating asymmetry (FA) in fingerprints is an indicator of type 2 diabetes mellitus (T2DM). Methods: Participants with T2DM, with T1DM, and without any indication or known family history of diabetes were fingerprinted with a Crossmatch Verifier 320 LC scanner. Asymmetry scores for each finger pair were assessed using both pattern analysis (ridge counts), and a wavelet-based analysis. Results: Both methods for scoring asymmetry predicted risk of T2DM for finger pair IV, controlling for gender and age. AUC scores were significantly greater than the null for pattern asymmetry scores (finger IV AUC = 0.74), and wavelet asymmetry scores for finger pair IV (AUC = 0.73) and finger pair V (AUC = 0.73), for predicting T2DM. In addition, wavelet asymmetry scores for finger pair IV (AUC = 0.80) and finger pair V (AUC = 0.85) significantly predicted risk of T1DM. Conclusions: A diagnostic tool based on FA in the fingerprints of finger pair IV, measured using a wavelet analysis could be developed for predicting risk prior to associated health problems for both T2DM and T1DM. In addition, given that that the prints for fingers IV and V develop during the 14-17 weeks of gestation, we predict that interventions during this time period of pregnancy will be most successful. PMID:26830490

Onset and Duration of Intravenous and Intraosseous Rocuronium in Swine

PubMed Central

Loughren, Michael; Banks, Sarah; Naluan, Carleo; Portenlanger, Paul; Wendorf, Arthur; Johnson, Don

2014-01-01

Introduction The intraosseous (IO) route has become a popular method to gain access to the peripheral circulation in emergency situations. Despite little supporting data, it is generally believed that IO absorption is immediate and equivalent to the intravenous (IV) route. It is important to determine if rocuronium can effectively be administered by the IO route. The aim of the study was to determine and compare the onset and duration of rocuronium when administered via the IO and IV routes in a normovolemic pig model. Methods We recorded electromyographic (EMG) data following tibial IO and peripheral IV administration of rocuronium (1.2 mg/kg) in 10 swine weighing between 56 and 71 Kg. We transformed data were transformed to percent of baseline, determined onset and recovery characteristics. Results The onset EMG-time profiles for IO and IV administration were very similar: tibial IO compared to IV administration did not statistically alter the onset of paralysis. The IO group took statistically longer than the IV group to return to 50 (p=0.042), 75 (p=0.034) and 95 (p=0.036) percent of baseline activity. Conclusion The duration of effect is statistically longer after IO administration but is more of an academic interest than a clinical concern. The results of this study suggest that rocuronium can effectively be administered via the IO route without the need for dose adjustments. PMID:24672619

Advantages and Disadvantages of the Amplatzer Vascular Plug IV in Visceral Embolization: Report of 50 Placements

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

Pech, Maciej, E-mail: maciej.pech@med.ovgu.de; Mohnike, Konrad; Wieners, Gero

2011-10-15

Purpose: We describe our initial clinical experience in artificial embolization with the Amplatzer Vascular Plug IV (VP IV), a further development of the Vascular Plug family already in routine use. Methods: Results from 50 embolization procedures conducted with the VP IV in 44 patients are summarized. Results: All 50 embolizations were successful, although two required the technique to be modified because of problems with jamming of the screw thread and thus with disconnection of the plug. This was associated with large branching angles. Conclusions: With experience, the VP IV can be used safely and effectively, and it expands the spectrummore » of possible embolizations in interventional radiology. Its greatest disadvantage is its relatively poor positional controllability.« less

Real-Time Series Resistance Monitoring in PV Systems Without the Need for I-V Curves

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

Deceglie, Michael G.; Silverman, Timothy J.; Marion, Bill

We apply the physical principles of a familiar method, suns-V oc, to a new application: the real-time detection of series resistance changes in modules and systems operating outside. The real-time series resistance (RTSR) method that we describe avoids the need for collecting I-V curves or constructing full series resistance-free I-V curves. RTSR is most readily deployable at the module level on microinverters or module-integrated electronics, but it can also be extended to full strings. We found that automated detection of series resistance increases can provide early warnings of some of the most common reliability issues, which also pose fire risks,more » including broken ribbons, broken solder bonds, and contact problems in the junction or combiner box. We also describe the method in detail and describe a sample application to data collected from modules operating in the field.« less

Real-Time Series Resistance Monitoring in PV Systems Without the Need for IV Curves

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

Deceglie, Michael G.; Silverman, Timothy J.; Marion, Bill

We apply the physical principles of a familiar method, suns-Voc, to a new application: the real-time detection of series resistance changes in modules and systems operating outside. The real-time series resistance (RTSR) method that we describe avoids the need for collecting IV curves or constructing full series-resistance-free IV curves. RTSR is most readily deployable at the module level on micro-inverters or module-integrated electronics, but it can also be extended to full strings. Automated detection of series resistance increases can provide early warnings of some of the most common reliability issues, which also pose fire risks, including broken ribbons, broken soldermore » bonds, and contact problems in the junction or combiner box. We describe the method in detail and describe a sample application to data collected from modules operating in the field.« less

An investigation of a PRESAGE® in-vivo dosimeter for brachytherapy

PubMed Central

Vidovic, A K; Juang, T; Meltsner, S; Adamovics, J; Chino, J; Steffey, B; Craciunescu, O; Oldham, M

2014-01-01

Determining accurate in-vivo dosimetry in brachytherapy treatment with high dose gradients is challenging. Here we introduce, investigate, and characterize a novel in-vivo dosimeter and readout technique with the potential to address this problem. A cylindrical (4 mm x 20 mm) tissue equivalent radiochromic dosimeter PRESAGE® In-Vivo (PRESAGE®-IV) is investigated. Two readout methods of the radiation induced change in optical density (OD) were investigated: (i) volume-averaged readout by spectrophotometer, and (ii) a line profile readout by 2D projection imaging utilizing a high-resolution (50 micron) telecentric optical system. Method (i) is considered the gold standard when applied to PRESAGE® in optical cuvettes. The feasibility of both methods was evaluated by comparison to standard measurements on PRESAGE® in optical cuvettes via spectrophotometer. An end-to-end feasibility study was performed by a side-by-side comparison with TLDs in an 192Ir HDR delivery. 7 and 8 Gy was delivered to PRESAGE®-IV and TLDs attached to the surface of a vaginal cylinder. Known geometry enabled direct comparison of measured dose with commissioned treatment planning system. A high-resolution readout study under a steep dose gradient region showed 98.9% (5%/1 mm) agreement between PRESAGE®-IV and Gafchromic® EBT2 Film. Spectrometer measurements exhibited a linear dose response between 0–15 Gy with sensitivity of 0.0133 ± 0.0007 ΔOD/(Gy·cm) at the 95% confidence interval. Method (ii) yielded a linear response with sensitivity of 0.0132 ± 0.0006 (ΔOD/Gy), within 2% of method (i). Method (i) has poor spatial resolution due to volume averaging. Method (ii) has higher resolution (~1mm) without loss of sensitivity or increased noise. Both readout methods are shown to be feasible. The end-to-end comparison revealed a 2.5% agreement between PRESAGE®-IV and treatment plan in regions of uniform high dose. PRESAGE®-IV shows promise for in-vivo dose verification, although improved sensitivity would be desirable. Advantages include high-resolution, convenience and fast, low-cost readout. PMID:24957850

An investigation of a PRESAGE® in vivo dosimeter for brachytherapy

NASA Astrophysics Data System (ADS)

Vidovic, A. K.; Juang, T.; Meltsner, S.; Adamovics, J.; Chino, J.; Steffey, B.; Craciunescu, O.; Oldham, M.

2014-07-01

Determining accurate in vivo dosimetry in brachytherapy treatment with high dose gradients is challenging. Here we introduce, investigate, and characterize a novel in vivo dosimeter and readout technique with the potential to address this problem. A cylindrical (4 mm × 20 mm) tissue equivalent radiochromic dosimeter PRESAGE® in vivo (PRESAGE®-IV) is investigated. Two readout methods of the radiation induced change in optical density (OD) were investigated: (i) volume-averaged readout by spectrophotometer, and (ii) a line profile readout by 2D projection imaging utilizing a high-resolution (50 micron) telecentric optical system. Method (i) is considered the gold standard when applied to PRESAGE® in optical cuvettes. The feasibility of both methods was evaluated by comparison to standard measurements on PRESAGE® in optical cuvettes via spectrophotometer. An end-to-end feasibility study was performed by a side-by-side comparison with TLDs in an 192Ir HDR delivery. 7 and 8 Gy was delivered to PRESAGE®-IV and TLDs attached to the surface of a vaginal cylinder. Known geometry enabled direct comparison of measured dose with a commissioned treatment planning system. A high-resolution readout study under a steep dose gradient region showed 98.9% (5%/1 mm) agreement between PRESAGE®-IV and Gafchromic® EBT2 Film. Spectrometer measurements exhibited a linear dose response between 0-15 Gy with sensitivity of 0.0133 ± 0.0007 ΔOD/(Gy ṡ cm) at the 95% confidence interval. Method (ii) yielded a linear response with sensitivity of 0.0132 ± 0.0006 (ΔOD/Gy), within 2% of method (i). Method (i) has poor spatial resolution due to volume averaging. Method (ii) has higher resolution (˜1 mm) without loss of sensitivity or increased noise. Both readout methods are shown to be feasible. The end-to-end comparison revealed a 2.5% agreement between PRESAGE®-IV and treatment plan in regions of uniform high dose. PRESAGE®-IV shows promise for in vivo dose verification, although improved sensitivity would be desirable. Advantages include high-resolution, convenience and fast, low-cost readout.

Advances in containment methods and plutonium recovery strategies that led to the structural characterization of plutonium(IV) tetrachloride tris-diphenylsulfoxide, PuCl 4(OSPh 2) 3

DOE PAGES

Schrell, Samantha K.; Boland, Kevin Sean; Cross, Justin Neil; ...

2017-01-18

In an attempt to further advance the understanding of plutonium coordination chemistry, we report a robust method for recycling and obtaining plutonium aqueous stock solutions that can be used as a convenient starting material in plutonium synthesis. This approach was used to prepare and characterize plutonium(IV) tetrachloride tris-diphenylsulfoxide, PuCl 4(OSPh 2) 3, by single crystal X-ray diffraction. The PuCl 4(OSPh 2) 3 compound represents a rare example of a 7-coordinate plutonium(IV) complex. Structural characterization of PuCl 4(OSPh 2) 3 by X-ray diffraction utilized a new containment method for radioactive crystals. The procedure makes use of epoxy, polyimide loops, and amore » polyester sheath to provide a robust method for safely containing and easily handling radioactive samples. Lastly, the described procedure is more user friendly than traditional containment methods that employ fragile quartz capillary tubes. Additionally, moving to polyester, instead of quartz, lowers the background scattering from the heavier silicon atoms.« less

Pedophilia: an evaluation of diagnostic and risk prediction methods.

PubMed

Wilson, Robin J; Abracen, Jeffrey; Looman, Jan; Picheca, Janice E; Ferguson, Meaghan

2011-06-01

One hundred thirty child sexual abusers were diagnosed using each of following four methods: (a) phallometric testing, (b) strict application of Diagnostic and Statistical Manual of Mental Disorders (4th ed., text revision [DSM-IV-TR]) criteria, (c) Rapid Risk Assessment of Sex Offender Recidivism (RRASOR) scores, and (d) "expert" diagnoses rendered by a seasoned clinician. Comparative utility and intermethod consistency of these methods are reported, along with recidivism data indicating predictive validity for risk management. Results suggest that inconsistency exists in diagnosing pedophilia, leading to diminished accuracy in risk assessment. Although the RRASOR and DSM-IV-TR methods were significantly correlated with expert ratings, RRASOR and DSM-IV-TR were unrelated to each other. Deviant arousal was not associated with any of the other methods. Only the expert ratings and RRASOR scores were predictive of sexual recidivism. Logistic regression analyses showed that expert diagnosis did not add to prediction of sexual offence recidivism over and above RRASOR alone. Findings are discussed within a context of encouragement of clinical consistency and evidence-based practice regarding treatment and risk management of those who sexually abuse children.

Room temperature current-voltage (I-V) characteristics of Ag/InGaN/n-Si Schottky barrier diode

NASA Astrophysics Data System (ADS)

Erdoğan, Erman; Kundakçı, Mutlu

2017-02-01

Metal-semiconductors (MSs) or Schottky barrier diodes (SBDs) have a significant potential in the integrated device technology. In the present paper, electrical characterization of Ag/InGaN/n-Si Schottky diode have been systematically carried out by simple Thermionic method (TE) and Norde function based on the I-V characteristics. Ag ohmic and schottky contacts are deposited on InGaN/n-Si film by thermal evaporation technique under a vacuum pressure of 1×10-5 mbar. Ideality factor, barrier height and series resistance values of this diode are determined from I-V curve. These parameters are calculated by TE and Norde methods and findings are given in a comparetive manner. The results show the consistency for both method and also good agreement with other results obtained in the literature. The value of ideality factor and barrier height have been determined to be 2.84 and 0.78 eV at room temperature using simple TE method. The value of barrier height obtained with Norde method is calculated as 0.79 eV.

L-arginine mediated renaturation enhances yield of human, α6 type IV collagen non-collagenous domain from bacterial inclusion bodies

PubMed Central

Gunda, Venugopal; Boosani, Chandra Shekhar; Verma, Raj Kumar; Guda, Chittibabu; Akul Sudhakar, Yakkanti

2012-01-01

The anti-angiogenic, carboxy terminal non-collagenous domain (NC1) derived from human Collagen type IV alpha 6 chain, [α6(IV)NC1] or hexastatin, was earlier obtained using different recombinant methods of expression in bacterial systems. However, the effect of L-arginine mediated renaturation in enhancing the relative yields of this protein from bacterial inclusion bodies has not been evaluated. In the present study, direct stirring and on-column renaturation methods using L-arginine and different size exclusion chromatography matrices were applied for enhancing the solubility in purifying the recombinant α6(IV)NC1 from bacterial inclusion bodies. This methodology enabled purification of higher quantities of soluble protein from inclusion bodies, which inhibited endothelial cell proliferation, migration and tube formation. Thus, the scope for L-arginine mediated renaturation in obtaining higher yields of soluble, biologically active NC1 domain from bacterial inclusion bodies was evaluated. PMID:22512648

L-arginine mediated renaturation enhances yield of human, α6 Type IV collagen non-collagenous domain from bacterial inclusion bodies.

PubMed

Gunda, Venugopal; Boosani, Chandra Shekhar; Verma, Raj Kumar; Guda, Chittibabu; Sudhakar, Yakkanti Akul

2012-10-01

The anti-angiogenic, carboxy terminal non-collagenous domain (NC1) derived from human Collagen type IV alpha 6 chain, [α6(IV)NC1] or hexastatin, was earlier obtained using different recombinant methods of expression in bacterial systems. However, the effect of L-arginine mediated renaturation in enhancing the relative yields of this protein from bacterial inclusion bodies has not been evaluated. In the present study, direct stirring and on-column renaturation methods using L-arginine and different size exclusion chromatography matrices were applied for enhancing the solubility in purifying the recombinant α6(IV)NC1 from bacterial inclusion bodies. This methodology enabled purification of higher quantities of soluble protein from inclusion bodies, which inhibited endothelial cell proliferation, migration and tube formation. Thus, the scope for L-arginine mediated renaturation in obtaining higher yields of soluble, biologically active NC1 domain from bacterial inclusion bodies was evaluated.

Estimating premorbid general cognitive functioning for children and adolescents using the American Wechsler Intelligence Scale for Children-Fourth Edition: demographic and current performance approaches.

PubMed

Schoenberg, Mike R; Lange, Rael T; Brickell, Tracey A; Saklofske, Donald H

2007-04-01

Neuropsychologic evaluation requires current test performance be contrasted against a comparison standard to determine if change has occurred. An estimate of premorbid intelligence quotient (IQ) is often used as a comparison standard. The Wechsler Intelligence Scale for Children-Fourth Edition (WISC-IV) is a commonly used intelligence test. However, there is no method to estimate premorbid IQ for the WISC-IV, limiting the test's utility for neuropsychologic assessment. This study develops algorithms to estimate premorbid Full Scale IQ scores. Participants were the American WISC-IV standardization sample (N = 2172). The sample was randomly divided into 2 groups (development and validation). The development group was used to generate 12 algorithms. These algorithms were accurate predictors of WISC-IV Full Scale IQ scores in healthy children and adolescents. These algorithms hold promise as a method to predict premorbid IQ for patients with known or suspected neurologic dysfunction; however, clinical validation is required.

Silica-gel Particles Loaded with an Ionic Liquid for Separation of Zr(IV) Prior to Its Determination by ICP-OES.

PubMed

Marwani, Hadi M; Alsafrani, Amjad E; Asiri, Abdullah M; Rahman, Mohammed M

2016-06-29

A new ionic liquid loaded silica gel amine (SG-APTMS-N,N-EPANTf₂) was developed, as an adsorptive material, for selective adsorption and determination of zirconium, Zr(IV), without the need for a chelating intermediate. Based on a selectivity study, the SG-APTMS-N,N-EPANTf₂ phase showed a perfect selectivity towards Zr(IV) at pH 4 as compared to other metallic ions, including gold [Au(III)], copper [Cu(II)], cobalt [Co(II)], chromium [Cr(III)], lead [Pb(II)], selenium [Se(IV)] and mercury [Hg(II)] ions. The influence of pH, Zr(IV) concentration, contact time and interfering ions on SG-APTMS-N,N-EPANTf₂ uptake for Zr(IV) was evaluated. The presence of incorporated donor atoms in newly synthesized SG-APTMS-N,N-EPANTf₂ phase played a significant role in enhancing its uptake capacity of Zr(IV) by 78.64% in contrast to silica gel (activated). The equilibrium and kinetic information of Zr(IV) adsorption onto SG-APTMS-N,N-EPANTf₂ were best expressed by Langmuir and pseudo second-order kinetic models, respectively. General co-existing cations did not interfere with the extraction and detection of Zr(IV). Finally, the analytical efficiency of the newly developed method was also confirmed by implementing it for the determination of Zr(IV) in several water samples.

The influence of rehydration mode after exercise dehydration on cardiovascular function.

PubMed

McDermott, Brendon P; Casa, Douglas J; Lee, Elaine C; Yamamoto, Linda M; Beasley, Kathleen N; Emmanuel, Holly; Pescatello, Linda S; Kraemer, William J; Anderson, Jeffrey M; Armstrong, Lawrence E; Maresh, Carl M

2013-08-01

Our purpose was to compare the common modes of rehydration (REHY) on cardiovascular and fluid regulation recovery after exercise dehydration (EXDE). Twelve nonheat-acclimatized trained subjects (age: 23 ± 4 years, weight: 81.3 ± 3.7 kg, height: 180 ± 6 cm, V[Combining Dot Above]O2max: 56.9 ± 4.4 ml·min·kg , and body fat: 7.8 ± 3.0%) completed 20-hour fluid restriction and 2-hour EXDE to -4% body mass, and then were rehydrated to -2% body mass in a randomized, crossover design. The REHY methods included no fluid (NF), ad libitum, oral (OR), intravenous (IV), and a combination of IV and OR (IV + OR) of 1/2-normal saline (0.45% NaCl). The REHY occurred for 30 minutes, and the subjects were observed during rest for 30 minutes. Seated, standing, and mean arterial pressure (MAP) and blood pressure (BP) were measured every 15 minutes throughout REHY. Heart rate (HR), plasma arginine vasopressin concentration [AVP], and thirst perception were measured throughout REHY. The EXDE resulted in a body mass loss of 4.32 ± 0.22%. The REHY returned the subjects to -2.13 ± 0.47% body mass for controlled trials. Seated systolic BP was greater for IV + OR compared with that for OR (p = 0.015). Seated systolic BP and MAP during REHY showed that IV + OR was greater than OR, independent of time (p ≤ 0.011). Upon standing, IV + OR demonstrated a greater BP than both NF (p = 0.012) and OR (p = 0.031) did. The HR was reduced by IV and IV + OR to a greater extent than NF at REHY30 and REHY60 (p < 0.05). The IV + OR [AVP] demonstrated a strong trend for decreasing over time (p = 0.054) and was significantly less than NF at REHY60 (p = 0.003). Practical application seeking to restore cardiovascular function after EXDE, the combined use of IV + OR rather than a single REHY method seems to be most expedient.

Single-layer group IV-V and group V-IV-III-VI semiconductors: Structural stability, electronic structures, optical properties, and photocatalysis

NASA Astrophysics Data System (ADS)

Lin, Jia-He; Zhang, Hong; Cheng, Xin-Lu; Miyamoto, Yoshiyuki

2017-07-01

Recently, single-layer group III monochalcogenides have attracted both theoretical and experimental interest at their potential applications in photonic devices, electronic devices, and solar energy conversion. Excited by this, we theoretically design two kinds of highly stable single-layer group IV-V (IV =Si ,Ge , and Sn; V =N and P) and group V-IV-III-VI (IV =Si ,Ge , and Sn; V =N and P; III =Al ,Ga , and In; VI =O and S) compounds with the same structures with single-layer group III monochalcogenides via first-principles simulations. By using accurate hybrid functional and quasiparticle methods, we show the single-layer group IV-V and group V-IV-III-VI are indirect bandgap semiconductors with their bandgaps and band edge positions conforming to the criteria of photocatalysts for water splitting. By applying a biaxial strain on single-layer group IV-V, single-layer group IV nitrides show a potential on mechanical sensors due to their bandgaps showing an almost linear response for strain. Furthermore, our calculations show that both single-layer group IV-V and group V-IV-III-VI have absorption from the visible light region to far-ultraviolet region, especially for single-layer SiN-AlO and SnN-InO, which have strong absorption in the visible light region, resulting in excellent potential for solar energy conversion and visible light photocatalytic water splitting. Our research provides valuable insight for finding more potential functional two-dimensional semiconductors applied in optoelectronics, solar energy conversion, and photocatalytic water splitting.

Coordination-Enabled One-Step Assembly of Ultrathin, Hybrid Microcapsules with Weak pH-Response.

PubMed

Yang, Chen; Wu, Hong; Yang, Xiao; Shi, Jiafu; Wang, Xiaoli; Zhang, Shaohua; Jiang, Zhongyi

2015-05-06

In this study, an ultrathin, hybrid microcapsule is prepared though coordination-enabled one-step assembly of tannic acid (TA) and titanium(IV) bis(ammonium lactate) dihydroxide (Ti-BALDH) upon a hard-templating method. Briefly, the PSS-doped CaCO3 microspheres with a diameter of 5-8 μm were synthesized and utilized as the sacrificial templates. Then, TA-Ti(IV) coatings were formed on the surface of the PSS-doped CaCO3 templates through soaking in TA and Ti-BALDH aqueous solutions under mild conditions. After removing the template by EDTA treatment, the TA-Ti(IV) microcapsules with a capsule wall thickness of 15 ± 3 nm were obtained. The strong coordination bond between polyphenol and Ti(IV) conferred the TA-Ti(IV) microcapsules high structural stability in the range of pH values 3.0-11.0. Accordingly, the enzyme-immobilized TA-Ti(IV) microcapsules exhibited superior pH and thermal stabilities. This study discloses the formation of TA-Ti(IV) microcapsules that are suitable for use as supports in catalysis due to their extensive pH and thermal stabilities.

Prevalence of "DSM-IV" Major Depression among Spanish University Students

ERIC Educational Resources Information Center

Vazquez, Fernando L.; Blanco, Vanessa

2008-01-01

Objective: The authors' purpose in this study was to estimate prevalence and correlates of "Diagnostic and Statistical Manual of Mental Disorders," 4th edition ("DSM-IV"), major depressive episodes (MDEs) among Spanish university students. Participants and Methods: In October and November 2004, interviewers administered a…

Reductive capacity measurement of waste forms for secondary radioactive wastes

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

Um, Wooyong; Yang, Jung-Seok; Serne, R. Jeffrey

2015-12-01

The reductive capacities of dry ingredients and final solid waste forms were measured using both the Cr(VI) and Ce(IV) methods and the results were compared. Blast furnace slag (BFS), sodium sulfide, SnF2, and SnCl2 used as dry ingredients to make various waste forms showed significantly higher reductive capacities compared to other ingredients regardless of which method was used. Although the BFS exhibits appreciable reductive capacity, it requires greater amounts of time to fully react. In almost all cases, the Ce(IV) method yielded larger reductive capacity values than those from the Cr(VI) method and can be used as an upper boundmore » for the reductive capacity of the dry ingredients and waste forms, because the Ce(IV) method subjects the solids to a strong acid (low pH) condition that dissolves much more of the solids. Because the Cr(VI) method relies on a neutral pH condition, the Cr(VI) method can be used to estimate primarily the waste form surface-related and readily dissolvable reductive capacity. However, the Cr(VI) method does not measure the total reductive capacity of the waste form, the long-term reductive capacity afforded by very slowly dissolving solids, or the reductive capacity present in the interior pores and internal locations of the solids.« less

Semiparametric methods for estimation of a nonlinear exposure-outcome relationship using instrumental variables with application to Mendelian randomization.

PubMed

Staley, James R; Burgess, Stephen

2017-05-01

Mendelian randomization, the use of genetic variants as instrumental variables (IV), can test for and estimate the causal effect of an exposure on an outcome. Most IV methods assume that the function relating the exposure to the expected value of the outcome (the exposure-outcome relationship) is linear. However, in practice, this assumption may not hold. Indeed, often the primary question of interest is to assess the shape of this relationship. We present two novel IV methods for investigating the shape of the exposure-outcome relationship: a fractional polynomial method and a piecewise linear method. We divide the population into strata using the exposure distribution, and estimate a causal effect, referred to as a localized average causal effect (LACE), in each stratum of population. The fractional polynomial method performs metaregression on these LACE estimates. The piecewise linear method estimates a continuous piecewise linear function, the gradient of which is the LACE estimate in each stratum. Both methods were demonstrated in a simulation study to estimate the true exposure-outcome relationship well, particularly when the relationship was a fractional polynomial (for the fractional polynomial method) or was piecewise linear (for the piecewise linear method). The methods were used to investigate the shape of relationship of body mass index with systolic blood pressure and diastolic blood pressure. © 2017 The Authors Genetic Epidemiology Published by Wiley Periodicals, Inc.

Semiparametric methods for estimation of a nonlinear exposure‐outcome relationship using instrumental variables with application to Mendelian randomization

PubMed Central

Staley, James R.

2017-01-01

ABSTRACT Mendelian randomization, the use of genetic variants as instrumental variables (IV), can test for and estimate the causal effect of an exposure on an outcome. Most IV methods assume that the function relating the exposure to the expected value of the outcome (the exposure‐outcome relationship) is linear. However, in practice, this assumption may not hold. Indeed, often the primary question of interest is to assess the shape of this relationship. We present two novel IV methods for investigating the shape of the exposure‐outcome relationship: a fractional polynomial method and a piecewise linear method. We divide the population into strata using the exposure distribution, and estimate a causal effect, referred to as a localized average causal effect (LACE), in each stratum of population. The fractional polynomial method performs metaregression on these LACE estimates. The piecewise linear method estimates a continuous piecewise linear function, the gradient of which is the LACE estimate in each stratum. Both methods were demonstrated in a simulation study to estimate the true exposure‐outcome relationship well, particularly when the relationship was a fractional polynomial (for the fractional polynomial method) or was piecewise linear (for the piecewise linear method). The methods were used to investigate the shape of relationship of body mass index with systolic blood pressure and diastolic blood pressure. PMID:28317167

The dynamic basis of energy transduction in enzymes.

PubMed

Somogyi, B; Welch, G R; Damjanovich, S

1984-09-06

The most important idea underlying our treatment herein is the unity of the enzyme molecule and the medium. Appreciation of this relationship is vital, if enzymology is to graduate from its present reductionistic status to a more holistic posture. Enzymes are biological entities firstly, and isolated objects of physicochemical analysis secondly. Perhaps the most crucial 'biological lesson', particularly apropos of enzymes in intermediary metabolism, concerns the 'cytosociology' of enzyme action in vivo [94,128]. The natural habitat of many enzymes in the living cell is far different from that in bulk aqueous solution in vitro. In order to obtain a real grasp of the nature of enzyme function, one must ultimately couch enzymology in concepts emerging from contemporary cell biology [95]. Notwithstanding, analysis precedes synthesis; and one must needs begin with the individual enzyme molecule. The trenchant efforts of the physical chemist and the organic chemist have produced a wealth of information on the nature of the binding and catalytic events at the enzyme active site. While it is not yet possible to explain precisely the complete sequence of events in the catalytic process, nevertheless, the basic mechanisms by which enzymes effect catalysis (i.e., reduce activation energy) now seem apparent [81,129]. The new frontier is to be found, in exploring the dynamic role of the protein matrix [17]. Not only does the protein provide the 3-D scaffolding for active-site processes, but, more importantly, it serves as the local solvent for the bound chemical subsystem. Thus, the dynamical aspects of enzyme catalysis (for thermally based systems) must arise from the fluctuational properties of the protein molecule. This notion is the common denominator in all of the models in subsection IIC. It is the anisotropic nature of this fluctuational behavior, which would characterize the energy-transduction phenomenon leading to localized catalytic events at the active-site. In Section III we attempted to show that all of the various enzyme models contribute pieces to a single, all-embracing jig-saw puzzle. Some models focus on the dynamical properties of the protein per se, whereas others deal with the stochastic aspects of protein-solvent interaction. The two approaches are complementary, as are mutually interlocking pieces of a puzzle. The ultimate picture depicted by this 'jig-saw puzzle' is still somewhat vague--owing to the present paucity of empirical information on protein motions.(ABSTRACT TRUNCATED AT 400 WORDS)

Dismantling processes of basaltic shield volcanoes - origin of the Piton des Neiges breccias - Reunion Island

NASA Astrophysics Data System (ADS)

Arnaud, A.; Bachèlery, B.; Cruchet, C.

2003-04-01

Reunion Island is mainly composed by two volcanic massifs: the active Piton de la Fournaise to the southeast and the Piton des Neiges to the northwest that has been inactive for about 12000 years. The latter corresponds to a dismantled volcanic massif, deeply cut by valleys and by three vast depressions, called “cirques” around the centre of the volcano. They offer the opportunity to observe the inside of a basaltic shield volcano. The first work dealing with the origin of the “cirques” very quickly showed the existence of a significant cover of breccia deposits. These breccias were often interpreted as the result of a major stage of erosion considered as partly at the origin of the “cirques” formation. Geological campaigns mainly achieved in the “cirque de Salazie” (eastern of the Piton des Neiges), allow to establish a first typology based on morphological, phenomenological and sedimentary features of the deposits. Two main complexes of breccias have been distinguished. An old complex outcropping in the internal parts of the cirque and an upper complex generally overlaying the lower complex. The old complex comprises two main units of breccias. These units show a strong alteration marked by the presence of clays, chlorites, serpentines and zeolites. In the inner part of the cirque, these breccias are closely related to the old lava formations from which they come. These units show frequent jigsaw-cracks, a chaotic stratigraphy, as well as large amounts of chlorite. The upper complex is constituted by four main units which are more or less geographically separated in the cirque of Salazie. Their limits are not yet well identified because of the significant relief and a strong vegetable cover. Several units display a very strong fracturation, jigsaw-cracks and a chaotic stratigraphy whereas many lava flows are pulverised and locally injected in scoria levels. Recent work on Saint-Gilles breccias (Fèvre et al., this meeting) allowed to identify several sub-aerials deposits of debris avalanches. These new data, the analysis of geology and sedimentary figures observed within the breccia units in the “cirque de Salazie”, evidence several major gravitational collapse affecting the northeast flank of Piton des Neiges volcano. Considering that, the “cirque de Salazie” appears as partly bounded by gravitational collapse affecting the flanks of the volcano.

Sensitive determination of carbohydrates by fluorimetric method with Ce(IV) and sodium triphosphate.

PubMed

Yang, Jinghe; Cao, Xihui; Sun, Changxia; Wu, Xia; Li, Lei

2004-05-01

A new simple and sensitive fluorimetric method for the determination of carbohydrates is described. The method is based on the reaction between carbohydrates and Ce(IV) in the presence of sulfuric acid. All the reductive carbohydrates can be detected indirectly by the fluorescence of Ce(III) produced. The addition of sodium triphate enhances the sensitivity of the method by more than 10-folds. Under optimum conditions, an excellent linear relationship was obtained between the fluorescence intensity and the concentration of carbohydrates. The limits of detection lie in the range of 9.3 x 10(-10) - 1.3 x 10(-9) mol/L. As compared to the normal fluorimetric method, the proposed method is faster and more sensitive.

Nonlinear excited waves on the interventricular septum

NASA Astrophysics Data System (ADS)

Bekki, Naoaki; Harada, Yoshifumi; Kanai, Hiroshi

2012-11-01

Using a novel ultrasonic noninvasive imaging method, we observe some phase singularities in propagating excited waves on a human cardiac interventricular septum (IVS) for a healthy young male. We present a possible physical model explaining one-dimensional dynamics of phase singularities in nonlinearly excited waves on the IVS. We show that at least one of the observed phase singularities in the excited waves on the IVS can be explained by the Bekki-Nozaki hole solution of the complex Ginzburg-Landau equation without any adjustable parameters. We conclude that the complex Ginzburg-Landau equation is such a suitable model for one-dimensional dynamics of cardiac phase singularities in nonlinearly excited waves on the IVS.

Hydrogen storage material and related processes

DOEpatents

Soloveichik, Grigorii Lev [Latham, NY; Andrus, Matthew John [Cape Canaveral, FL

2012-06-05

Disclosed herein is a composition comprising a complex hydride and a borohydride catalyst wherein the borohydride catalyst comprises a BH.sub.4 group, and a group IV metal, a group V metal, or a combination of a group IV and a group V metal. Also disclosed herein are methods of making the composition.

Hydrogen storage material and related processes

DOEpatents

Soloveichik; Grigorii Lev , Andrus; Matthew John

2010-07-13

Disclosed herein is a composition comprising a complex hydride and a borohydride catalyst wherein the borohydride catalyst comprises a BH.sub.4 group, and a group IV metal, a group V metal, or a combination of a group IV and a group V metal. Also disclosed herein are methods of making the composition.

78 FR 18325 - Defense Transportation Regulation, Part IV

Federal Register 2010, 2011, 2012, 2013, 2014

2013-03-26

... received in connection with the Defense Personal Property Program (DP3) Phase III Direct Procurement Method... at http://www.transcom.mil/dtr/part-iv/phaseiii.cfm (DPM SECTION). All identified changes will be... Defense Personal Property System (DPS) Phase III programming projected for FY17. FOR FURTHER INFORMATION...

Degradation study of AlAs/GaAs resonant tunneling diode IV curves under influence of high temperatures

NASA Astrophysics Data System (ADS)

Makeev, M. O.; Meshkov, S. A.; Sinyakin, V. Yu

2017-11-01

In the present work the thermal degradation of IV curves of AlAs/GaAs resonant tunneling diodes using artificial aging method was investigated. The dependency of AuGeNi specific ohmic contact resistance on time and temperature was determined.

Visual and surface plasmon resonance sensor for zirconium based on zirconium-induced aggregation of adenosine triphosphate-stabilized gold nanoparticles.

PubMed

Qi, Wenjing; Zhao, Jianming; Zhang, Wei; Liu, Zhongyuan; Xu, Min; Anjum, Saima; Majeed, Saadat; Xu, Guobao

2013-07-17

Owing to its high affinity with phosphate, Zr(IV) can induce the aggregation of adenosine 5'-triphosphate (ATP)-stabilized AuNPs, leading to the change of surface plasmon resonance (SPR) absorption spectra and color of ATP-stabilized AuNP solutions. Based on these phenomena, visual and SPR sensors for Zr(IV) have been developed for the first time. The A(660 nm)/A(518 nm) values of ATP-stabilized AuNPs in SPR absorption spectra increase linearly with the concentrations of Zr(IV) from 0.5 μM to 100 μM (r=0.9971) with a detection limit of 95 nM. A visual Zr(IV) detection is achieved with a detection limit of 30 μM. The sensor shows excellent selectivity against other metal ions, such as Cu(2+), Fe(3+), Cd(2+), and Pb(2+). The recoveries for the detection of 5 μM, 10 μM, 25 μM and 75 μM Zr(IV) in lake water samples are 96.0%, 97.0%, 95.6% and 102.4%, respectively. The recoveries of the proposed SPR method are comparable with those of ICP-OES method. Copyright © 2013 Elsevier B.V. All rights reserved.

Speciation of inorganic tellurium from seawater by ICP-MS following magnetic SPE separation and preconcentration.

PubMed

Huang, Chaozhang; Hu, Bin

2008-03-01

A new method was developed for the speciation of inorganic tellurium species in seawater by inductively coupled plasma-MS (ICP-MS) following selective magnetic SPE (MSPE) separation. Within the pH range of 2-9, tellurite (Te(IV)) could be quantitatively adsorbed on gamma-mercaptopropyltrimethoxysilane (gamma-MPTMS) modified silica-coated magnetic nanoparticles (MNPs), while the tellurate (Te(VI)) was not retained and remained in solution. Without filtration or centrifugation, these tellurite-loaded MNPs could be separated easily from the aqueous solution by simply applying external magnetic field. The Te(IV) adsorbed on the MNPs could be recovered quantitatively using a solution containing 2 mol/L HCl and 0.03 mol/L K2Cr2O7. Te(VI) was reduced to Te(IV) by L-cysteine prior to the determination of total tellurium, and its assay was based on subtracting Te(IV) from total tellurium. The parameters affecting the separation were investigated systematically and the optimal separation conditions were established. Under the optimal conditions, the LOD obtained for Te(IV) was 0.079 ng/L, while the precision was 7.0% (C = 10 ng/L, n = 7). The proposed method was successfully applied to the speciation of inorganic tellurium in seawater.

Subcutaneous Crotaline Fab antivenom for the treatment of rattlesnake envenomation in a porcine model.

PubMed

Offerman, Steven R; Barry, J David; Richardson, William H; Tong, Tri; Tanen, Dave; Bush, Sean P; Clark, Richard F

2009-01-01

This study was designed to investigate whether the local, subcutaneous injection of Crotaline Fab antivenom (CroFab) at the rattlesnake envenomation site would result in less extremity edema when compared to intravenous (i.v.) antivenom infusion alone. This is a randomized, three-arm laboratory experiment using a porcine model. Each animal was anesthetized, intubated, and maintained on mechanical ventilation. About 6 mg/kg of Crotalus atrox venom was injected subcutaneously at the hock of the right hind leg. Animals were then randomized to immediately receive subcutaneous and i.v. antivenom (SC/IV), i.v. antivenom only, or saline control. SC/IV animals received two vials of CroFab subcutaneously at the envenomation site and two vials intravenously. IV animals received four vials of CroFab intravenously. Limb edema was tracked by serial circumference and volumetric measurements over an 8-h period. Limb circumference was measured at four pre-determined locations hourly. Limb volume was measured by a water displacement method at baseline, 4, and 8 h. Twenty-six animals were randomized to the three treatment groups. The SC/IV and IV arms included nine animals each. Two animals in the SC/IV group died suddenly during the study, leaving seven animals for data analysis. There were eight controls. Increasing limb edema was observed in all groups. No differences were detected in limb circumferences or limb volumes between control and either treatment arms. In this porcine model of crotaline envenomation, no differences in limb edema were found between animals treated with SC/IV or IV CroFab when compared to saline controls.

Chronic production of angiotensin IV in the brain leads to hypertension that is reversible with an angiotensin II AT1 receptor antagonist.

PubMed

Lochard, Nadheige; Thibault, Gaétan; Silversides, David W; Touyz, Rhian M; Reudelhuber, Timothy L

2004-06-11

Angiotensin IV (Ang IV) is a metabolite of the potent vasoconstrictor angiotensin II (Ang II). Because specific binding sites for this peptide have been reported in numerous tissues including the brain, it has been suggested that a specific Ang IV receptor (AT4) might exist. Bolus injection of Ang IV in brain ventricles has been implicated in learning, memory, and localized vasodilatation. However, the functions of Ang IV in a physiological context are still unknown. In this study, we generated a transgenic (TG) mouse model that chronically releases Ang IV peptide specifically in the brain. TG mice were found to be hypertensive by the tail-cuff method as compared with control littermates. Treatment with the angiotensin-converting enzyme inhibitor captopril had no effect on blood pressure, but surprisingly treatment with the Ang II AT1 receptor antagonist candesartan normalized the blood pressure despite the fact that the levels of Ang IV in the brains of TG mice were only 4-fold elevated over the normal endogenous level of Ang peptides. Calcium mobilization assays performed on cultured CHO cells chronically transfected with the AT1 receptor confirm that low-dose Ang IV can mobilize calcium via the AT1 receptor only in the presence of Ang II, consistent with an allosteric mechanism. These results suggest that chronic elevation of Ang IV in the brain can induce hypertension that can be treated with angiotensin II AT1 receptor antagonists.

PaCeQuant: A Tool for High-Throughput Quantification of Pavement Cell Shape Characteristics.

PubMed

Möller, Birgit; Poeschl, Yvonne; Plötner, Romina; Bürstenbinder, Katharina

2017-11-01

Pavement cells (PCs) are the most frequently occurring cell type in the leaf epidermis and play important roles in leaf growth and function. In many plant species, PCs form highly complex jigsaw-puzzle-shaped cells with interlocking lobes. Understanding of their development is of high interest for plant science research because of their importance for leaf growth and hence for plant fitness and crop yield. Studies of PC development, however, are limited, because robust methods are lacking that enable automatic segmentation and quantification of PC shape parameters suitable to reflect their cellular complexity. Here, we present our new ImageJ-based tool, PaCeQuant, which provides a fully automatic image analysis workflow for PC shape quantification. PaCeQuant automatically detects cell boundaries of PCs from confocal input images and enables manual correction of automatic segmentation results or direct import of manually segmented cells. PaCeQuant simultaneously extracts 27 shape features that include global, contour-based, skeleton-based, and PC-specific object descriptors. In addition, we included a method for classification and analysis of lobes at two-cell junctions and three-cell junctions, respectively. We provide an R script for graphical visualization and statistical analysis. We validated PaCeQuant by extensive comparative analysis to manual segmentation and existing quantification tools and demonstrated its usability to analyze PC shape characteristics during development and between different genotypes. PaCeQuant thus provides a platform for robust, efficient, and reproducible quantitative analysis of PC shape characteristics that can easily be applied to study PC development in large data sets. © 2017 American Society of Plant Biologists. All Rights Reserved.

Polyethylene glycol assisted growth of Sn-doped ZnO nanorod arrays prepared via sol-gel immersion method

NASA Astrophysics Data System (ADS)

Ismail, A. S.; Mamat, M. H.; Malek, M. F.; Saidi, S. A.; Yusoff, M. M.; Mohamed, R.; Sin, N. D. Md; Suriani, A. B.; Rusop, M.

2018-05-01

Tin-doped zinc oxide (SZO) nanorod films at different concentrations of polyethylene glycol (PEG) were successfully deposited on zinc oxide (ZnO) seeded layer catalyst using sol-gel immersion method. The morphology of the samples were characterized using field emission scanning electron microscopy (FESEM), optical properties using UV-Vis spectrophotometer and electrical properties using I-V measurement system. The current-voltage (I-V) characteristics displayed that 5 wt % sample produced the highest conductivity.

A photometric study of the dwarf spheroidal galaxies Leo IV and Bootes II

NASA Astrophysics Data System (ADS)

Cheng, Haw

A photometric study of the ultra-faint dwarf (UFD) galaxies Leo IV and Bootes II in the V and IC filters is here presented. The age of Leo IV relative to M92 were derived by fitting of Dartmouth isochrones, by a "standard" VHBTO method, and by the V HBTO method of VandenBerg et al. 2013. The age of Bootes II relative to M92 was derived by fitting of Dartmouth isochrones. Leo IV is found to be between 2 to 2.5 Gyr younger than M92 by these three methods. It is found to be predominantly old and metal poor and is well fit by isochrones of [Fe/H] = ---2.46 and [alpha/Fe] = 0.2 and 0.4. An age spread with a plausible value of ˜ 2 Gyr cannot be ruled out. A 10 Gyr old synthetic horizontal branch with [Fe/H] = ---1.70 and [alpha/Fe] of 0.2 is fit to Leo IV's red horizontal branch (RHB). The good fit of this model and its matching isochrone to Leo IV's CMD suggests that the RHB is real and not an observational artifact as proposed by Okamoto et al. 2012. Two RRab Lyraes previously observed by Moretti et al. 2009 were observed in Leo IV. One of the stars, V1, is observed to exhibit the Blazhko effect. No further RR Lyraes were uncovered in Leo IV. Comparison of the horizontal branch's observed V magnitude to the absolute magnitudes of the RR Lyraes yields a distance modulus of (m---M)0 = 21.01 +/- 0.07, in good agreement with previous studies. Leo IV's possible population of blue stragglers is found to show no signs of central concentration, though this study's sample and spatial coverage are too small for any detailed spatial distribution study. Bootes II's CMD is found to be consistent with that of a single age, mono-metallicity system. It is well fit by isochrones of [Fe/H] = ---1.79 and [alpha/Fe] = 0.2 and 0.4. Bootes II is found to be between 0.5 to 1.5 Gyr younger than M92. Distance was left as a free parameter in the fits. Bootes II is found to have distance modulus (m---M)0 lying between 18.02 to 18.15, in good agreement with previous studies. A single RRab Lyrae is discovered in Bootes II.

Utility of NBD-Cl for the spectrophotometric determination of some skeletal muscle relaxant and antihistaminic drugs

NASA Astrophysics Data System (ADS)

Saleh, Hanaa M.; EL-Henawee, Magda M.; Ragab, Gamal H.; El-Hay, Soad S. Abd

2007-08-01

A simple, accurate, precise and sensitive colorimetric method for the determination of some skeletal muscle relaxant drugs, namely orphenadrine citrate ( I), baclofen ( II), antihistaminic drugs as acrivastine ( III) and fexofenadine hydrochloride ( IV) is described. This method is based on the formation of charge transfer complex with 4-chloro-7-nitro-2,1,3-benzoxadiazole (NBD-Cl) in non-aqueous medium. The orange color products were measured at 472, 465, 475 and 469 nm for drugs I, II, III and IV, respectively. The optimization of various experimental conditions was described. Beer's Law was obeyed in the range (2.5-17.5), (5-70), (2.5-25) and (10-50) μg/ml for drugs I, II, III and IV, respectively. The molar absorptivity ( ɛ), sandell sensitivity, detection (LOD) and quantitation limits (LOQ) are calculated. The procedure was favorably applied for determination of certain pharmaceutical dosage forms containing the studied drugs. The obtained results were compared with the official and reported methods. There were no significant differences between proposed, reported and the official methods.

The radio-frequency fluctuation effect on the floating harmonic method

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

Lee, Jaewon; Kim, Kyung-Hyun; Kim, Dong-Hwan

2016-08-15

The radio-frequency (RF) plasma diagnostics with an electrical probe facing a challenge, because the RF fluctuation oscillates the plasma potential and distorts the current-voltage (I-V) curve. As Langmuir probe is widely used in plasma diagnostics, many researchers have been studying the effect of RF fluctuation on probe and compensation methods. On the other hand, there have not been enough studies on the fluctuation effect on the floating harmonic method. Therefore, we investigated the impact of RF fluctuation on the floating harmonic method theoretically and experimentally. When the electrons are in ideal Maxwellian distribution, the floating potential is negatively shifted bymore » the RF fluctuation, but the fluctuation does not distort I-V curve around the floating potential. However, in practical plasmas, the I-V curve and their harmonic components are distorted. This RF fluctuation effect becomes more significant in a low density plasma with a high impedance sheath. The second harmonic current decreases with the RF fluctuation while the first harmonic current is merely affected. Therefore, the electron temperatures measured with the floating harmonic method under low density plasma with uncompensated probe are overestimated than the results obtained with the compensated probe.« less

The structure of DSM-IV-TR personality disorder diagnoses in NESARC: a reanalysis.

PubMed

Trull, Timothy J; Vergés, Alvaro; Wood, Phillip K; Sher, Kenneth J

2013-12-01

Cox, Clara, Worobec, and Grant (2012) recently presented results from a series of analyses aimed at identifying the factor structure underlying the DSM-IV-TR (APA, 2000) personality diagnoses assessed in the large NESARC study. Cox et al. (2012) concluded that the best fitting model was one that modeled three lower-order factors (the three clusters of PDs as outlined by DSM-IV-TR), which in turn loaded on a single PD higher-order factor. Our reanalyses of the NESARC Wave 1 and Wave 2 data for personality disorder diagnoses revealed that the best fitting model was that of a general PD factor that spans each of the ten DSM-IV PD diagnoses, and our reanalyses do not support the three-cluster hierarchical structure outlined by Cox et al. (2012) and DSM-IV-TR. Finally, we note the importance of modeling the Wave 2 assessment method factor in analyses of NESARC PD data.

Method development and survey of Sudan I–IV in palm oil and chilli spices in the Washington, DC, area

PubMed Central

Genualdi, Susie; MacMahon, Shaun; Robbins, Katherine; Farris, Samantha; Shyong, Nicole; DeJager, Lowri

2016-01-01

Sudan I, II, III and IV dyes are banned for use as food colorants in the United States and European Union because they are toxic and carcinogenic. These dyes have been illegally used as food additives in products such as chilli spices and palm oil to enhance their red colour. From 2003 to 2005, the European Union made a series of decisions requiring chilli spices and palm oil imported to the European Union to contain analytical reports declaring them free of Sudan I–IV. In order for the USFDA to investigate the adulteration of palm oil and chilli spices with unapproved colour additives in the United States, a method was developed for the extraction and analysis of Sudan dyes in palm oil, and previous methods were validated for Sudan dyes in chilli spices. Both LC-DAD and LC-MS/MS methods were examined for their limitations and effectiveness in identifying adulterated samples. Method validation was performed for both chilli spices and palm oil by spiking samples known to be free of Sudan dyes at concentrations close to the limit of detection. Reproducibility, matrix effects, and selectivity of the method were also investigated. Additionally, for the first time a survey of palm oil and chilli spices was performed in the United States, specifically in the Washington, DC, area. Illegal dyes, primarily Sudan IV, were detected in palm oil at concentrations from 150 to 24 000 ng ml−1. Low concentrations (< 21 μg kg−1) of Sudan dyes were found in 11 out of 57 spices and are most likely a result of cross-contamination during preparation and storage and not intentional adulteration. PMID:26824489

Method development and survey of Sudan I-IV in palm oil and chilli spices in the Washington, DC, area.

PubMed

Genualdi, Susie; MacMahon, Shaun; Robbins, Katherine; Farris, Samantha; Shyong, Nicole; DeJager, Lowri

2016-01-01

Sudan I, II, III and IV dyes are banned for use as food colorants in the United States and European Union because they are toxic and carcinogenic. These dyes have been illegally used as food additives in products such as chilli spices and palm oil to enhance their red colour. From 2003 to 2005, the European Union made a series of decisions requiring chilli spices and palm oil imported to the European Union to contain analytical reports declaring them free of Sudan I-IV. In order for the USFDA to investigate the adulteration of palm oil and chilli spices with unapproved colour additives in the United States, a method was developed for the extraction and analysis of Sudan dyes in palm oil, and previous methods were validated for Sudan dyes in chilli spices. Both LC-DAD and LC-MS/MS methods were examined for their limitations and effectiveness in identifying adulterated samples. Method validation was performed for both chilli spices and palm oil by spiking samples known to be free of Sudan dyes at concentrations close to the limit of detection. Reproducibility, matrix effects, and selectivity of the method were also investigated. Additionally, for the first time a survey of palm oil and chilli spices was performed in the United States, specifically in the Washington, DC, area. Illegal dyes, primarily Sudan IV, were detected in palm oil at concentrations from 150 to 24 000 ng ml(-1). Low concentrations (< 21 µg kg(-1)) of Sudan dyes were found in 11 out of 57 spices and are most likely a result of cross-contamination during preparation and storage and not intentional adulteration.

Thermometric titrimetry Studies of the cerium(IV) oxidation of alpha-mercaptocarboxylic acids.

PubMed

Alexander, W A; Mash, C J; McAuley, A

1969-04-01

The cerium(IV) oxidation of thioglycollic, thiolactic and thiomalic acids has been examined by thermometric titration. The titration curves indicate stoichiometries of more than 1 mole of cerium(IV) per mole of alpha-thiol, suggesting possible side-reactions. In the presence of methyl acrylate, however, the expected ratio is observed. The overall heat of each reaction has been derived. Only with a titration method of this kind where allowance can be made for side-reactions can the heats of reaction for these systems be measured.

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

Despotopulos, John D.; Kmak, Kelly N.; Gharibyan, Narek

Eichrom’s Pb resin, a crown-ether-based extraction chromatography resin, was characterized for separation of the flerovium (Fl) homologs, Pb and Sn. Batch uptake of Pb(II) and Sn(IV) radionuclides was determined from an HNO 3 matrix. Pb(II) was strongly retained on the resin at all HNO 3 concentrations, while Sn(IV) showed no uptake. Extraction kinetics for Pb(II) were examined and show suitable uptake on the second time scale. Here, separation methods for the isolation of individual homologs, Pb(II) and Sn(IV), have been established using 2 mL pre-packed vacuum flow Pb resin columns.

Predictive Validity of DSM-IV and ICD-10 Criteria for ADHD and Hyperkinetic Disorder

ERIC Educational Resources Information Center

Lee, Soyoung I.; Schachar, Russell J.; Chen, Shirley X.; Ornstein, Tisha J.; Charach, Alice; Barr, Cathy; Ickowicz, Abel

2008-01-01

Background: The goal of this study was to compare the predictive validity of the two main diagnostic schemata for childhood hyperactivity--attention-deficit hyperactivity disorder (ADHD; "Diagnostic and Statistical Manual"-IV) and hyperkinetic disorder (HKD; "International Classification of Diseases"-10th Edition). Methods: Diagnostic criteria for…

Efficacy and Safety of Lisdexamfetamine Dimesylate in Adolescents with Attention-Deficit/Hyperactivity Disorder

ERIC Educational Resources Information Center

Findling, Robert L.; Childress, Ann C.; Cutler, Andrew J.; Gasior, Maria; Hamdani, Mohamed; Ferreira-Cornwell, M. Celeste; Squires, Liza

2011-01-01

Objective: To examine lisdexamfetamine dimesylate (LDX) efficacy and safety versus placebo in adolescents with attention-deficit/hyperactivity disorder (ADHD). Method: Adolescents (13 through 17) with at least moderately symptomatic ADHD (ADHD Rating Scale IV: Clinician Version [ADHD-RS-IV] score greater than or equal to 28) were randomized to…

29 CFR 4022.82 - Method of recoupment.

Code of Federal Regulations, 2013 CFR

2013-07-01

... by the present value of the benefit payable with respect to the participant under title IV of ERISA... the present value of the benefit to which a participant or beneficiary is entitled under title IV of... determine the present value of that amount as of the termination date, using PBGC interest rates and factors...

29 CFR 4022.82 - Method of recoupment.

Code of Federal Regulations, 2014 CFR

2014-07-01

... by the present value of the benefit payable with respect to the participant under title IV of ERISA... the present value of the benefit to which a participant or beneficiary is entitled under title IV of... determine the present value of that amount as of the termination date, using PBGC interest rates and factors...

29 CFR 4022.82 - Method of recoupment.

Code of Federal Regulations, 2011 CFR

2011-07-01

... determine the fractional multiplier by dividing the amount of the net overpayment by the present value of... the present value of the benefit to which a participant or beneficiary is entitled under title IV of... by the present value of the benefit payable with respect to the participant under title IV of ERISA...

29 CFR 4022.82 - Method of recoupment.

Code of Federal Regulations, 2012 CFR

2012-07-01

... by the present value of the benefit payable with respect to the participant under title IV of ERISA... the present value of the benefit to which a participant or beneficiary is entitled under title IV of... determine the present value of that amount as of the termination date, using PBGC interest rates and factors...

WISC-IV Profiles Are Associated with Differences in Symptomatology and Outcome in Children with ADHD

ERIC Educational Resources Information Center

Thaler, Nicholas S.; Bello, Danielle T.; Etcoff, Lewis M.

2013-01-01

Objective: The current study investigated the Wechsler Intelligence Scale for Children-Fourth Edition (WISC-IV) cluster profiles of children with ADHD to examine the association between IQ profiles and diagnostic frequency, symptomatology, and outcome in this population. Method: Hierarchical cluster analysis was conducted on 189 children with a…

Selenium speciation using capillary electrophoresis coupled with modified electrothermal atomic absorption spectrometry after selective extraction with 5-sulfosalicylic acid functionalized magnetic nanoparticles.

PubMed

Yan, Lizhen; Deng, Biyang; Shen, Caiying; Long, Chanjuan; Deng, Qiufen; Tao, Chunyao

2015-05-22

A new method for selenium speciation in fermented bean curd wastewater and juice was described. This method involved sample extraction with 5-sulfosalicylic acid (SSA)-functionalized silica-coated magnetic nanoparticles (SMNPs), capillary electrophoresis (CE) separation, and online detection with a modified electrothermal atomic absorption spectrometry (ETAAS) system. The modified interface for ETAAS allowed for the introduction of CE effluent directly through the end of the graphite tube. Elimination of the upper injection hole of the graphite tube reduced the loss of the anlayte and enhanced the detection sensitivity. The SSA-SMNPs were synthesized and used to extract trace amounts of selenite [Se(IV)], selenite [Se(VI)], selenomethionine (SeMet), and selenocystine (SeCys2) from dilute samples. The concentration enrichment factors for Se(VI), Se(IV), SeMet, and SeCys2 were 21, 29, 18, and 12, respectively, using the SSA-SMNPs extraction. The limits of detection for Se(VI), Se(IV), SeMet, and SeCys2 were 0.18, 0.17, 0.54, 0.49ngmL(-1), respectively. The RSD values (n=6) of method for intraday were observed between 0.7% and 2.9%. The RSD values of method for interday were less than 3.5%. The linear range of Se(VI) and Se(IV) were in the range of 0.5-200ngmL(-1), and the linear ranges of SeMet and SeCys2 were 2-500 and 2-1000ngmL(-1), respectively. The detection limits of this method were improved by 10 times due to the enrichment by the SSA-SMNP extraction. The contents of Se(VI) and Se(IV) in fermented bean curd wastewater were measured as 3.83 and 2.62ngmL(-1), respectively. The contents of Se(VI), Se(IV), SeMet, and SeCys2 in fermented bean curd juice were determined as 6.39, 4.08, 2.77, and 4.00ngmL(-1), respectively. The recoveries were in the range of 99.14-104.5% and the RSDs (n=6) of recoveries between 0.82% and 3.5%. Copyright © 2015 Elsevier B.V. All rights reserved.

Quantifying and Reducing Curve-Fitting Uncertainty in Isc

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

Campanelli, Mark; Duck, Benjamin; Emery, Keith

2015-06-14

Current-voltage (I-V) curve measurements of photovoltaic (PV) devices are used to determine performance parameters and to establish traceable calibration chains. Measurement standards specify localized curve fitting methods, e.g., straight-line interpolation/extrapolation of the I-V curve points near short-circuit current, Isc. By considering such fits as statistical linear regressions, uncertainties in the performance parameters are readily quantified. However, the legitimacy of such a computed uncertainty requires that the model be a valid (local) representation of the I-V curve and that the noise be sufficiently well characterized. Using more data points often has the advantage of lowering the uncertainty. However, more data pointsmore » can make the uncertainty in the fit arbitrarily small, and this fit uncertainty misses the dominant residual uncertainty due to so-called model discrepancy. Using objective Bayesian linear regression for straight-line fits for Isc, we investigate an evidence-based method to automatically choose data windows of I-V points with reduced model discrepancy. We also investigate noise effects. Uncertainties, aligned with the Guide to the Expression of Uncertainty in Measurement (GUM), are quantified throughout.« less

The prevalence of ADHD in a population-based sample

PubMed Central

Rowland, Andrew S.; Skipper, Betty J.; Umbach, David M.; Rabiner, David L.; Campbell, Richard A.; Naftel, A. Jack; Sandler, Dale P.

2014-01-01

Objective Few studies of ADHD prevalence have used population-based samples, multiple informants, and DSM-IV criteria. In addition, children who are asymptomatic while receiving ADHD mediction often have been misclassified. Therefore, we conducted a population-based study to estimate the prevalence of ADHD in elementary school children using DSM-IV critera. Methods We screened 7587 children for ADHD. Teachers of 81% of the children completed a DSM-IV checklist. We then interviewed parents using a structured interview (DISC). Of these, 72% participated. Parent and teacher ratings were combined to determine ADHD status. We also estimated the proportion of cases attributable to other conditions. Results Overall, 15.5% of our sample (95% confidence interval (C.I.) 14.6%-16.4%) met DSM-IV-TR criteria for ADHD. Over 40% of cases reported no previous diagnosis. With additional information, other conditions explained about 9% of cases. Conclusions The prevalence of ADHD in this population-based sample was higher than the 3-7% commonly reported. To compare study results, the methods used to implement the DSM criteria need to be standardized. PMID:24336124

A systematic method of interconnection optimization for dense-array concentrator photovoltaic system.

PubMed

Siaw, Fei-Lu; Chong, Kok-Keong

2013-01-01

This paper presents a new systematic approach to analyze all possible array configurations in order to determine the most optimal dense-array configuration for concentrator photovoltaic (CPV) systems. The proposed method is fast, simple, reasonably accurate, and very useful as a preliminary study before constructing a dense-array CPV panel. Using measured flux distribution data, each CPV cells' voltage and current values at three critical points which are at short-circuit, open-circuit, and maximum power point are determined. From there, an algorithm groups the cells into basic modules. The next step is I-V curve prediction, to find the maximum output power of each array configuration. As a case study, twenty different I-V predictions are made for a prototype of nonimaging planar concentrator, and the array configuration that yields the highest output power is determined. The result is then verified by assembling and testing of an actual dense-array on the prototype. It was found that the I-V curve closely resembles simulated I-V prediction, and measured maximum output power varies by only 1.34%.

Comparison of FLAASH and QUAC atmospheric correction methods for Resourcesat-2 LISS-IV data

NASA Astrophysics Data System (ADS)

Saini, V.; Tiwari, R. K.; Gupta, R. P.

2016-05-01

The LISS-IV sensor aboard Resourcesat-2 is a modern relatively high resolution multispectral sensor having immense potential for generation of good quality land use land cover maps. It generates data in high (10-bit) radiometric resolution and 5.8 m spatial resolution and has three bands in the visible-near infrared region. This is of particular importance to global community as the data are provided at highly competitive prices. However, no literature describing the atmospheric correction of Resourcesat-2-LISS-IV data could be found. Further, without atmospheric correction full radiometric potential of any remote sensing data remains underutilized. The FLAASH and QUAC module of ENVI software are highly used by researchers for atmospheric correction of popular remote sensing data such as Landsat, SPOT, IKONOS, LISS-I, III etc. This article outlines a methodology for atmospheric correction of Resourcesat-2-LISS-IV data. Also, a comparison of reflectance from different atmospheric correction modules (FLAASH and QUAC) with TOA and standard data has been made to determine the best suitable method for reflectance estimation for this sensor.

3-D simulation of nanopore structure for DNA sequencing.

PubMed

Park, Jun-Mo; Pak, Y Eugene; Chun, Honggu; Lee, Jong-Ho

2012-07-01

In this paper, we propose a method for simulating nanopore structure by using conventional 3-D simulation tool to mimic the I-V behavior of the nanopore structure. In the simulation, we use lightly doped silicon for ionic solution where some parameters like electron affinity and dielectric constant are fitted to consider the ionic solution. By using this method, we can simulate the I-V behavior of nanopore structure depending on the location and the size of the sphere shaped silicon oxide which is considered to be an indicator of a DNA base. In addition, we simulate an Ionic Field Effect Transistor (IFET) which has basically the nanopore structure, and show that the simulated curves follow sufficiently the I-V behavior of the measurement data. Therefore, we think it is reasonable to apply parameter modeling mentioned above to simulate nanopore structure. The key idea is to modify electron affinity of silicon which is used to mimic the KCl solution to avoid band bending and depletion inside the nanopore. We could efficiently utilize conventional 3-D simulation tool to simulate the I-V behavior of nanopore structures.

Quantifying and Reducing Curve-Fitting Uncertainty in Isc: Preprint

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

Campanelli, Mark; Duck, Benjamin; Emery, Keith

Current-voltage (I-V) curve measurements of photovoltaic (PV) devices are used to determine performance parameters and to establish traceable calibration chains. Measurement standards specify localized curve fitting methods, e.g., straight-line interpolation/extrapolation of the I-V curve points near short-circuit current, Isc. By considering such fits as statistical linear regressions, uncertainties in the performance parameters are readily quantified. However, the legitimacy of such a computed uncertainty requires that the model be a valid (local) representation of the I-V curve and that the noise be sufficiently well characterized. Using more data points often has the advantage of lowering the uncertainty. However, more data pointsmore » can make the uncertainty in the fit arbitrarily small, and this fit uncertainty misses the dominant residual uncertainty due to so-called model discrepancy. Using objective Bayesian linear regression for straight-line fits for Isc, we investigate an evidence-based method to automatically choose data windows of I-V points with reduced model discrepancy. We also investigate noise effects. Uncertainties, aligned with the Guide to the Expression of Uncertainty in Measurement (GUM), are quantified throughout.« less

A Systematic Method of Interconnection Optimization for Dense-Array Concentrator Photovoltaic System

PubMed Central

Siaw, Fei-Lu

2013-01-01

This paper presents a new systematic approach to analyze all possible array configurations in order to determine the most optimal dense-array configuration for concentrator photovoltaic (CPV) systems. The proposed method is fast, simple, reasonably accurate, and very useful as a preliminary study before constructing a dense-array CPV panel. Using measured flux distribution data, each CPV cells' voltage and current values at three critical points which are at short-circuit, open-circuit, and maximum power point are determined. From there, an algorithm groups the cells into basic modules. The next step is I-V curve prediction, to find the maximum output power of each array configuration. As a case study, twenty different I-V predictions are made for a prototype of nonimaging planar concentrator, and the array configuration that yields the highest output power is determined. The result is then verified by assembling and testing of an actual dense-array on the prototype. It was found that the I-V curve closely resembles simulated I-V prediction, and measured maximum output power varies by only 1.34%. PMID:24453823

Determination of total antioxidant capacity by a new spectrophotometric method based on Ce(IV) reducing capacity measurement.

PubMed

Ozyurt, Dilek; Demirata, Birsen; Apak, Resat

2007-02-28

Dietary antioxidants widely found in fruits and vegetables may serve the task of reducing oxidative damage in humans induced by free radicals and reactive oxygen species under 'oxidative stress' conditions. The aim of this work is to develop a simple, low-cost, sensitive, and diversely applicable indirect spectrophotometric method for the determination of total antioxidant capacity of several plants. The method is based on the oxidation of antioxidants with cerium(IV) sulfate in dilute sulfuric acid at room temperature. The Ce(IV) reducing capacity of the sample is measured under carefully adjusted conditions of oxidant concentration and pH such that only antioxidants and not other organic compounds would be oxidized. The spectrophotometric determination of the remaining Ce(IV) was performed after completion of reaction with antioxidants. Quercetin and gallic acid were used as standards for flavonoids and phenolic acids, respectively, and results of antioxidant measurements were reported as trolox equivalents. The developed procedure was successfully applied to the assay of total antioxidant capacity due to simple compounds such as trolox, quercetin, gallic acid, ascorbic acid, catechin, naringin, naringenin, caffeic acid, chlorogenic acid, ferulic acid, and p-coumaric acid, and due to phenolic acids and flavonoids in the arieal parts of nettle (Urtica Dioica L.). Blank correction of significantly absorbing plant extracts at 320nm could be made with the aid of spectrophotometric titration. Plant selection was made in respect to high antioxidant content, and extraction was made with water. The proposed method was reproducible, and the trolox equivalent antioxidant capacities (TEAC coefficients) of the tested antioxidant compounds were correlated to those found by reference methods such as ABTS and CUPRAC. Since the TEAC coefficients found with the proposed method of naringin-naringenin and rutin-catechin pairs were close to each other, this Ce(IV)-based assay probably caused the simultaneous hydrolysis of flavonoid glycosides to the corresponding aglycones and their subsequent oxidation such that the hydrolysis products exhibed antioxidant capacities roughly proportional the number of -OH groups contained in a molecule.

Detection of Cardiac Quiescence from B-Mode Echocardiography Using a Correlation-Based Frame-to-Frame Deviation Measure

PubMed Central

Mcclellan, James H.; Ravichandran, Lakshminarayan; Tridandapani, Srini

2013-01-01

Two novel methods for detecting cardiac quiescent phases from B-mode echocardiography using a correlation-based frame-to-frame deviation measure were developed. Accurate knowledge of cardiac quiescence is crucial to the performance of many imaging modalities, including computed tomography coronary angiography (CTCA). Synchronous electrocardiography (ECG) and echocardiography data were obtained from 10 healthy human subjects (four male, six female, 23–45 years) and the interventricular septum (IVS) was observed using the apical four-chamber echocardiographic view. The velocity of the IVS was derived from active contour tracking and verified using tissue Doppler imaging echocardiography methods. In turn, the frame-to-frame deviation methods for identifying quiescence of the IVS were verified using active contour tracking. The timing of the diastolic quiescent phase was found to exhibit both inter- and intra-subject variability, suggesting that the current method of CTCA gating based on the ECG is suboptimal and that gating based on signals derived from cardiac motion are likely more accurate in predicting quiescence for cardiac imaging. Two robust and efficient methods for identifying cardiac quiescent phases from B-mode echocardiographic data were developed and verified. The methods presented in this paper will be used to develop new CTCA gating techniques and quantify the resulting potential improvement in CTCA image quality. PMID:26609501

Analgesic Activity of Some 1,2,4-Triazole Heterocycles Clubbed with Pyrazole, Tetrazole, Isoxazole and Pyrimidine

PubMed Central

Gajanan Khanage, Shantaram; Raju, Appala; Baban Mohite, Popat; Bhanudas Pandhare, Ramdas

2013-01-01

Purpose: In the present study in vivo analgesic activity of some previously synthesized 1,2,4-triazole derivatives containing pyrazole, tetrazole, isoxazole and pyrimidine ring have been evaluated. Methods: Acetic acid induced writhing method and Hot plate method has been described to study analgesic activity of some 1,2,4-triazole derivatives containing pyrazole, tetrazole, isoxazole and pyrimidine as a pharmacological active lead. Results: Thirty six different derivatives containing 1,2,4-triazole ring were subjected to study their in vivo analgesic activity. Chloro, nitro and methoxy, hydroxy and bromo substituted derivatives showed excellent analgesic activity and dimethylamino, furan and phenyl substituted derivatives showed moderate analgesic activity in both of the methods. Compounds IIIa, IIId, IIIf, IIIi, IIIj, IVa, IVb, IVd, IVf, IVh, IVj IV3a and IIj were found to be superior analgesic agents after screening by Acetic acid induced writhing method. Compounds IIIb, IIId, IIIf, IIIh, IIIj, IVa, IVb, IVd, IVf, IVh, IVi, IV3c, IV3e and IIj were showed analgesic potential after screening of Hot plate method. Conclusion: All tested compounds containing 1,2,4-triazole were found to be promising analgesic agents, for this activity pyrazole, tetrazole, isoxazole and pyrimidine leads might be supported. PMID:24312806

46 CFR 160.077-5 - Incorporation by reference.

Code of Federal Regulations, 2013 CFR

2013-10-01

..., Breaking of Woven Cloth; Grab Method. (ii) Method 5132, Strength of Cloth, Tearing; Falling-Pendulum Method. (iii) Method 5134, Strength of Cloth, Tearing; Tongue Method. (iv) Method 5804.1, Weathering Resistance of Cloth; Accelerated Weathering Method. (v) Method 5762, Mildew Resistance of Textile Materials...

46 CFR 160.077-5 - Incorporation by reference.

Code of Federal Regulations, 2014 CFR

2014-10-01

..., Breaking of Woven Cloth; Grab Method. (ii) Method 5132, Strength of Cloth, Tearing; Falling-Pendulum Method. (iii) Method 5134, Strength of Cloth, Tearing; Tongue Method. (iv) Method 5804.1, Weathering Resistance of Cloth; Accelerated Weathering Method. (v) Method 5762, Mildew Resistance of Textile Materials...

Synchronous fluorescence determination of ferulic acid with Ce(IV) and sodium tripolyphosphate.

PubMed

Meng, F; Liu, P; Huang, F; Wang, L; Wu, X; Shen, L

2014-05-01

In this study, a synchronous fluorescence detection method for ferulic acid (FA) is proposed based on a redox reaction between FA and Ce(IV) sulfate in dilute sulfuric acid medium at room temperature. It was found that FA could reduce Ce(IV) to Ce(III) in acidic medium, and sodium tripolyphosphate could further enhance the intrinsic fluorescence of the Ce(III) produced. The enhanced extent of synchronous fluorescence intensity was in proportion to the concentration of FA over the range 3.0 × 10(-8) to 1.0 × 10(-5) mol/L. The corresponding limit of determination (S/N = 3) was 1.3 × 10(-8) mol/L. The proposed method was applied to the determination of sodium ferulate for injection sample with satisfactory results. Copyright © 2013 John Wiley & Sons, Ltd.

The Fentanyl Patch Boil-Up - A Novel Method of Opioid Abuse.

PubMed

Schauer, Cameron K M W; Shand, James A D; Reynolds, Thomas M

2015-11-01

Fentanyl is a potent opioid analgesic used in the treatment of pain. Transdermal fentanyl patches are now widely utilized as an acceptable and efficacious method of medication delivery. Unfortunately, the potential for their abuse is well recognized. Previous case reports have documented deaths after intravenous (IV) misuse of fentanyl which had been extracted from Duragesic (liquid reservoir type) patches. We present a case of IV fentanyl abuse after the extraction from a Mylan (matrix type) patch. This method of abuse has not previously been described in the literature. © 2015 Nordic Association for the Publication of BCPT (former Nordic Pharmacological Society).

Comparison Between Individually and Group-Based Insulin Pump Initiation by Time-Driven Activity-Based Costing

PubMed Central

Ridderstråle, Martin

2017-01-01

Background: Depending on available resources, competencies, and pedagogic preference, initiation of insulin pump therapy can be performed on either an individual or a group basis. Here we compared the two models with respect to resources used. Methods: Time-driven activity-based costing (TDABC) was used to compare initiating insulin pump treatment in groups (GT) to individual treatment (IT). Activities and cost drivers were identified, timed, or estimated at location. Medical quality and patient satisfaction were assumed to be noninferior and were not measured. Results: GT was about 30% less time-consuming and 17% less cost driving per patient and activity compared to IT. As a batch driver (16 patients in one group) GT produced an upward jigsaw-shaped accumulative cost curve compared to the incremental increase incurred by IT. Taking the alternate cost for those not attending into account, and realizing the cost of opportunity gained, suggested that GT was cost neutral already when 5 of 16 patients attended, and that a second group could be initiated at no additional cost as the attendance rate reached 15:1. Conclusions: We found TDABC to be effective in comparing treatment alternatives, improving cost control and decision making. Everything else being equal, if the setup is available, our data suggest that initiating insulin pump treatment in groups is far more cost effective than on an individual basis and that TDABC may be used to find the balance point. PMID:28366085

Magic in the machine: a computational magician's assistant

PubMed Central

Williams, Howard; McOwan, Peter W.

2014-01-01

A human magician blends science, psychology, and performance to create a magical effect. In this paper we explore what can be achieved when that human intelligence is replaced or assisted by machine intelligence. Magical effects are all in some form based on hidden mathematical, scientific, or psychological principles; often the parameters controlling these underpinning techniques are hard for a magician to blend to maximize the magical effect required. The complexity is often caused by interacting and often conflicting physical and psychological constraints that need to be optimally balanced. Normally this tuning is done by trial and error, combined with human intuitions. Here we focus on applying Artificial Intelligence methods to the creation and optimization of magic tricks exploiting mathematical principles. We use experimentally derived data about particular perceptual and cognitive features, combined with a model of the underlying mathematical process to provide a psychologically valid metric to allow optimization of magical impact. In the paper we introduce our optimization methodology and describe how it can be flexibly applied to a range of different types of mathematics based tricks. We also provide two case studies as exemplars of the methodology at work: a magical jigsaw, and a mind reading card trick effect. We evaluate each trick created through testing in laboratory and public performances, and further demonstrate the real world efficacy of our approach for professional performers through sales of the tricks in a reputable magic shop in London. PMID:25452736

Zirconium(IV) functionalized magnetic nanocomposites for extraction of organophosphorus pesticides from environmental water samples.

PubMed

Jiang, Li; Huang, Tengjun; Feng, Shun; Wang, Jide

2016-07-22

The widespread use of organophosphate pesticides (OPPs) in agriculture leads to residue accumulation in the environment which is dangerous to human health and disrupts the ecological balance. In this work, one nanocomposite immobilized zirconium (Zr, IV) was prepared and used as the affinity probes to quickly and selectively extract organophosphorus pesticides (OPPs) from water samples. The Fe3O4-ethylenediamine tetraacetic acid (EDTA)@Zr(IV) nanocomposites (NPs) were prepared by simply mixing Zr(IV) ions with Fe3O4-EDTA NPs synthesized by one-pot chemical co-precipitation method. The immobilized Zr(IV) ions were further utilized to capture OPPs based on their high affinity for the phosphate moiety in OPPs. Coupled with GC-MS, four OPPs were used as models to demonstrate the feasibility of this approach. Under the optimum conditions, the limits of detection for target OPPs were in the range of 0.10-10.30ngmL(-1) with relative standard deviations (RSDs) of 0.61-4.40% (n=3), respectively. The linear ranges were over three orders of magnitudes (correlation coefficients, R(2)>0.9995). The Fe3O4-EDTA@Zr(IV) NPs were successfully applied to extract OPPs samples with recoveries of 86.95-112.60% and RSDs of 1.20-10.42% (n=3) from two spiked real water. By the proposed method, the matrix interference could be effectively eliminated. We hope our finding can provide a promising alternative for the fast extraction of OPPs from complex real samples. Copyright © 2016 Elsevier B.V. All rights reserved.

Educating to the seismic risk with the community of learners

NASA Astrophysics Data System (ADS)

Miranda, Nicola

2013-04-01

The web has a lot of information available for teachers about seismology both at informal and at a scientific level. The average student, who approaches the study of seismology for the first time, lacks direct involvement in the study and it often happens that the simple informal knowledge does not result in learning and formalization. The teacher who wants to use web resources for the didactics, finds it is difficult to select information and adapt it to the school level, because of the short weekly time reserved for earth science studies. The seismologist, who gives a lecture in the school, has difficulty to understand how much of the knowledge transmitted will pass to the students. A way to solve these problems is to adopt the Community of Learners' method, creating groups of different-aged students directly involved in research activities and in the production of learning material, using websites organized for web research, production and sharing of ideas, as Jigsaw methodology suggests. The poster shown documents the experience I had with a group of students (aged from 14 to 18) in an Italian high school in Somma Vesuviana, near Naples. The method adopted is adaptable to any kind of technical-scientific issue. In this case seismology was the topic of the work group and thanks to the Community of Learners' method, all the students: -Started as apprentices, learning new things, questioning their knowledge, accessing new sources, using different channels and means of communication and debating with the others; -Moved to the role of teachers, sharing their own knowledge with the others, and explaining their own discoveries; -Became scientists specialized in something unknown to the other students, producers of new and original ideas to explain to the others who had different opinions and ideas. Thanks to the Community of Learners, they all became apprentices, teachers and scientists.

Printed-Circuit-Board Soldering Training for Group IV Personnel.

ERIC Educational Resources Information Center

Hooprich, E. A.; Matlock, E. W.

As part of a larger program to determine which Navy skills can be learned by lower aptitude personnel, and which methods and techniques would be most effective, an experimental course in printed circuit board soldering was given to 186 Group IV students in 13 classes. Two different training approaches--one stressing instructor guidance and the…

Simple, Fast and Effective Correction for Irradiance Spatial Nonuniformity in Measurement of IVs of Large Area Cells at NREL

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

Moriarty, Tom

The NREL cell measurement lab measures the IV parameters of cells of multiple sizes and configurations. A large contributing factor to errors and uncertainty in Jsc, Imax, Pmax and efficiency can be the irradiance spatial nonuniformity. Correcting for this nonuniformity through its precise and frequent measurement can be very time consuming. This paper explains a simple, fast and effective method based on bicubic interpolation for determining and correcting for spatial nonuniformity and verification of the method's efficacy.

The fabrication of nitrogen detector porous silicon nanostructures

NASA Astrophysics Data System (ADS)

Husairi, F. S.; Othman, N.; Eswar, K. A.; Guliling, Muliyadi; Khusaimi, Z.; Rusop, M.; Abdullah, S.

2018-05-01

In this study the porous silicon nanostructure used as a the nitrogen detector was fabricated by using anodization method because of simple and easy to handle. This method using 20 mA/ cm2 of current density and the etching time is from 10 - 40 minutes. The properties of the porous silicon nanostructure analyzed using I-V testing (electrical properties) and photoluminescence spectroscopy. From the I-V testing, sample PsiE40 where the sensitivity is 25.4% is a sensitivity of PSiE40 at 10 seconds exposure time.

Assessment of Semi-Structured Clinical Interview for Mobile Phone Addiction Disorder

PubMed Central

Alavi, Seyyed Salman; Jannatifard, Fereshteh; Mohammadi Kalhori, Soroush; Sepahbodi, Ghazal; BabaReisi, Mohammad; Sajedi, Sahar; Farshchi, Mojtaba; KhodaKarami, Rasul; Hatami Kasvaee, Vahid

2016-01-01

Objective: The Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition, Text Revision (DSM-IV-TR) classified mobile phone addiction disorder under “impulse control disorder not elsewhere classified”. This study surveyed the diagnostic criteria of DSM-IV-TR for the diagnosis of mobile phone addiction in correspondence with Iranian society and culture. Method: Two hundred fifty students of Tehran universities were entered into this descriptive-analytical and cross-sectional study. Quota sampling method was used. At first, semi- structured clinical interview (based on DSM-IV-TR) was performed for all the cases, and another specialist reevaluated the interviews. Data were analyzed using content validity, inter-scorer reliability (Kappa coefficient) and test-retest via SPSS18 software. Results: The content validity of the semi- structured clinical interview matched the DSM–IV-TR criteria for behavioral addiction. Moreover, their content was appropriate, and two items, including “SMS pathological use” and “High monthly cost of using the mobile phone” were added to promote its validity. Internal reliability (Kappa) and test–retest reliability were 0.55 and r = 0.4 (p<0. 01) respectively. Conclusion: The results of this study revealed that semi- structured diagnostic criteria of DSM-IV-TR are valid and reliable for diagnosing mobile phone addiction, and this instrument is an effective tool to diagnose this disorder. PMID:27437008

Equipoise among recanalization strategies.

PubMed

Tomsick, T A; Khatri, P; Jovin, T; Demaerschalk, B; Malisch, T; Demchuk, A; Hill, M D; Jauch, E; Spilker, J; Broderick, J P

2010-03-30

Modern acute ischemic stroke therapy is based on the premise that recanalization and subsequent reperfusion are essential for the preservation of brain tissue and favorable clinical outcomes. We outline key issues that we think underlie equipoise regarding the comparative clinical efficacy of IV recombinant tissue-type plasminogen activator (rt-PA) and intra-arterial (IA) reperfusion therapies for acute ischemic stroke. On the one hand, IV rt-PA therapy has the benefit of speed with presumed lower rates of recanalization of large artery occlusions as compared to IA methods. More recent reports of major arterial occlusions treated with IV rt-PA, as measured by transcranial Doppler and magnetic resonance angiography, demonstrate higher rates of recanalization. Conversely, IA therapies report higher recanalization rates, but are hampered by procedural delays and risks, even failing to be applied at all in occasional patients where time to reperfusion remains a critical factor. Higher rates of recanalization in IA trials using clot-removal devices have not translated into improved patient functional outcome as compared to trials of IV therapy. Combined IV-IA therapy promises to offer advantages of both, but perhaps only when applied in the timeliest of fashions, compared to IV therapy alone. Where equipoise exists, randomizing subjects to either IV rt-PA therapy or IV therapy followed by IA intervention, while incorporating new interventions into the study design, is a rational and appropriate research approach.

Distribution of type IV collagen in pancreatic adenocarcinoma and chronic pancreatitis.

PubMed Central

Lee, C. S.; Montebello, J.; Georgiou, T.; Rode, J.

1994-01-01

Changes in the basement membrane are present in various neoplastic conditions such as neurofibrosarcoma, cervical carcinoma, colorectal cancers and hepatoblastoma. This study examines the expression of type IV collagen in the basement membrane, using an immunohistochemical method, in the normal pancreas (n = 10), chronic pancreatitis (n = 15) and pancreatic adenocarcinoma (n = 30). The formalin fixed, paraffin embedded tissue was sectioned and pretreated with protease prior to immunostaining for type IV collagen. There was a statistically significant difference in type IV collagen expression between pancreatic carcinoma and chronic pancreatitis (P = 0.0001; chi 2 test with continuity correction). In pancreatic adenocarcinoma, type IV collagen distribution in the basement membrane was discontinuous and irregular or absent around individual or groups of neoplastic cells (n = 30). Most cases of chronic pancreatitis showed continuous pattern of basement membrane type IV collagen around residual ducts (n = 10). In the normal pancreas, only one of the ten cases showed discontinuous basement membrane around pancreatic ducts, while in the rest of the cases, the pattern was continuous. This study suggests that there is abnormal distribution of type IV collagen in the basement membrane in pancreatic carcinoma, which may be related to either abnormal deposition or degradation of the collagen. Immunostaining for type IV collagen may be of some diagnostic use for distinguishing pancreatic adenocarcinoma from problematic cases of chronic pancreatitis. Images Figure 1 Figure 2 Figure 3 PMID:8199008

Systematic Evaluation of Wajima Superposition (Steady-State Concentration to Mean Residence Time) in the Estimation of Human Intravenous Pharmacokinetic Profile.

PubMed

Lombardo, Franco; Berellini, Giuliano; Labonte, Laura R; Liang, Guiqing; Kim, Sean

2016-03-01

We present a systematic evaluation of the Wajima superpositioning method to estimate the human intravenous (i.v.) pharmacokinetic (PK) profile based on a set of 54 marketed drugs with diverse structure and range of physicochemical properties. We illustrate the use of average of "best methods" for the prediction of clearance (CL) and volume of distribution at steady state (VDss) as described in our earlier work (Lombardo F, Waters NJ, Argikar UA, et al. J Clin Pharmacol. 2013;53(2):178-191; Lombardo F, Waters NJ, Argikar UA, et al. J Clin Pharmacol. 2013;53(2):167-177). These methods provided much more accurate prediction of human PK parameters, yielding 88% and 70% of the prediction within 2-fold error for VDss and CL, respectively. The prediction of human i.v. profile using Wajima superpositioning of rat, dog, and monkey time-concentration profiles was tested against the observed human i.v. PK using fold error statistics. The results showed that 63% of the compounds yielded a geometric mean of fold error below 2-fold, and an additional 19% yielded a geometric mean of fold error between 2- and 3-fold, leaving only 18% of the compounds with a relatively poor prediction. Our results showed that good superposition was observed in any case, demonstrating the predictive value of the Wajima approach, and that the cause of poor prediction of human i.v. profile was mainly due to the poorly predicted CL value, while VDss prediction had a minor impact on the accuracy of human i.v. profile prediction. Copyright © 2016. Published by Elsevier Inc.

Are symptoms of spirit possessed patients covered by the DSM-IV or DSM-5 criteria for possession trance disorder? A mixed-method explorative study in Uganda.

PubMed

van Duijl, Marjolein; Kleijn, Wim; de Jong, Joop

2013-09-01

As in many cultures, spirit possession is a common idiom of distress in Uganda. The DSM-IV contains experimental research criteria for dissociative and possession trance disorder (DTD and PTD), which are under review for the DSM-5. In the current proposed categories of the DSM-5, PTD is subsumed under dissociative identity disorder (DID) and DTD under dissociative disorders not elsewhere classified. Evaluation of these criteria is currently urgently required. This study explores the match between local symptoms of spirit possession in Uganda and experimental research criteria for PTD in the DSM-IV and proposed criteria for DID in the DSM-5. A mixed-method approach was used combining qualitative and quantitative research methods. Local symptoms were explored of 119 spirit possessed patients, using illness narratives and a cultural dissociative symptoms' checklist. Possible meaningful clusters of symptoms were inventoried through multiple correspondence analysis. Finally, local symptoms were compared with experimental criteria for PTD in the DSM-IV and proposed criteria for DID in the DSM-5. Illness narratives revealed different phases of spirit possession, with passive-influence experiences preceding the actual possession states. Multiple correspondence analysis of symptoms revealed two dimensions: 'passive' and 'active' symptoms. Local symptoms, such as changes in consciousness, shaking movements, and talking in a voice attributed to spirits, match with DSM-IV-PTD and DSM-5-DID criteria. Passive-influence experiences, such as feeling influenced or held by powers from outside, strange dreams, and hearing voices, deserve to be more explicitly described in the proposed criteria for DID in the DSM-5. The suggested incorporation of PTD in DID in the DSM-5 and the envisioned separation of DTD and PTD in two distinctive categories have disputable aspects.

Simultaneous detection of Hb constant spring (α142, TAA>CAA, α2) and the α2 IVS-I donor site (-TGAGG) deletion by a simple polymerase chain reaction-based method in Iran.

PubMed

Akhavan-Niaki, Haleh; Banihashemi, Ali; Mostafazadeh, Amrollah; Kholghi Oskooei, Vahid; Azizi, Mandana; Youssefi Kamangar, Reza; Elmi, Maryam Mitra

2012-01-01

Hb Constant Spring (Hb CS, codon 142, TAA>CAA, α2) (HBA2:c.427T>C) and α2 IVS-I donor site (GAGGTGAGG>GAGG - - - - -) (HBA2:c.95+2_95+6delTGAGG) are nondeletional α-thalassemia (α-thal) mutations found all over the world. Identification of α-thal genotypes in at-risk couples for severe anemia or in highly heterogeneous populations requires rapid, accurate and cost-effective genotyping methods. In this study, a pair of primers were used to specifically amplify an 883 bp fragment from the α2-globin gene in order to simultaneously identify these two mutations by a PCR-RFLP (polymerase chain reaction-restriction fragment length polymorphism) method. We determined the genotypic frequencies of Hb CS and the α2 IVS-I donor site mutations after amplification and enzymatic digestion with Tru9I in 238 northern Iranian samples referred for α-thal testing. Hb CS and the α2 IVS-I donor site mutations accounted for 21 (8.8%) and 29 (12.2%) of the nondeletional cases. This genotyping assay has proven to be a rapid, reliable and useful diagnostic tool for simultaneous detection of these two anomalies for genetic counseling or further prenatal diagnosis.

Selenium speciation in radix puerariae using ultrasonic assisted extraction combined with reversed phase high performance liquid chromatography-inductively coupled plasma-mass spectrometry after magnetic solid-phase extraction with 5-sulfosalicylic acid functionalized magnetic nanoparticles

NASA Astrophysics Data System (ADS)

Cao, Yupin; Yan, Lizhen; Huang, Hongli; Deng, Biyang

2016-08-01

A new method for determination of selenium species in radix puerariae was described. The method consists of sample enrichment with 5-sulfosalicylic acid (SSA)-functionalized silica-coated magnetic nanoparticles (SMNPs), high performance liquid chromatography (HPLC) separation, and online detection using inductively coupled plasma mass spectrometry (ICP-MS). The selenium species were extracted using ultrasonic extraction system with a mixture of protease K and lipase. The SSA-SMNPs were used to enrich trace amounts of selenite [Se(IV)], selenate [Se(VI)], selenomethionine (SeMet), and selenocystine (SeCys2) from lower selenium containing samples. Under the optimal conditions, the limits of detection (3σ) for SeCys2, Se(IV), SeMet and Se(VI) were observed as 0.0023, 0.0015, 0.0043, and 0.0016 ng mL- 1, respectively. The RSD values (n = 6) of method for intraday were observed between 0.5% and 0.9%. The RSD values of method for interday were less than 1.3%. The linear concentration ranges for SeCys2, Se(IV), SeMet and Se(VI) were 0.008-1000, 0.005-200, 0.015-500 and 0.006-200 ng mL- 1, respectively. The detection limits of this method were improved by 10 times due to the enrichment with the SSA-SMNP extraction. The contents of SeCys2, Se(IV), SeMet, and Se(VI) in radix puerariae were determined as 0.0140, 0.171, 0.0178, and 0.0344 μg g- 1, respectively. The recoveries were in the range of 95.6%-99.4% and the RSDs (n = 6) of recoveries were less than 1.5%.

Application of F⁺RNA Coliphages as Source Tracking Enteric Viruses on Parsley and Leek Using RT-PCR.

PubMed

Shahrampour, Dina; Yavarmanesh, Masoud; Najafi, Mohammad Bagher Habibi; Mohebbi, Mohebbat

2015-12-01

The objective of this study was to identify sources of fecal contamination in leek and parsley, by using four different F(+)RNA coliphage genogroups (IV, I indicate animal fecal contamination and II, III indicate human fecal contamination). Three different concentrations (10(2), 10(4), 10(6) pfu/ml) of MS2 coliphage were inoculated on the surface of parsley and leek samples for detection of phage recovery efficiency among two methods of elution concentration (PEG-precipitation and Ultracentrifugation) by performing double agar layer (DAL) assay in three replications. Highest recovery of MS2 was observed in PEG method and in 10(6) inoculation concentration. Accordingly, the PEG method was used for washing and isolation of potentially contaminated phages of 30 collected samples (15 samples from the market and 15 samples from the farm). The final solutions of PEG method were tested for the enumeration of plaques by DAL assay. Total RNA was then extracted from recovered phages, and RT-PCR was performed by using four primer sets I, II, III, and IV. Incidence of F(+)RNA coliphages was observed in 12/15 (80 %) and 10/15 (66/6 %) of samples were obtained from farm and market, respectively, using both DAL and RT-PCR test methods. Different genotypes (I, II, and IV) of F(+)RNA coliphages were found in farm samples, while only genotype I was detected in market samples by using the primer sets. Due to the higher frequency of genotype I and IV, the absence of genotype III, and also the low frequency of genotype II, it is concluded that the contamination of vegetable (parsley and leek) in Neyshabour, Iran is most likely originated from animal sources.

The Extrapolation of High Altitude Solar Cell I(V) Characteristics to AM0

NASA Technical Reports Server (NTRS)

Snyder, David B.; Scheiman, David A.; Jenkins, Phillip P.; Reinke, William; Blankenship, Kurt; Demers, James

2007-01-01

The high altitude aircraft method has been used at NASA GRC since the early 1960's to calibrate solar cell short circuit current, ISC, to Air Mass Zero (AMO). This method extrapolates ISC to AM0 via the Langley plot method, a logarithmic extrapolation to 0 air mass, and includes corrections for the varying Earth-Sun distance to 1.0 AU and compensating for the non-uniform ozone distribution in the atmosphere. However, other characteristics of the solar cell I(V) curve do not extrapolate in the same way. Another approach is needed to extrapolate VOC and the maximum power point (PMAX) to AM0 illumination. As part of the high altitude aircraft method, VOC and PMAX can be obtained as ISC changes during the flight. These values can then the extrapolated, sometimes interpolated, to the ISC(AM0) value. This approach should be valid as long as the shape of the solar spectra in the stratosphere does not change too much from AMO. As a feasibility check, the results are compared to AMO I(V) curves obtained using the NASA GRC X25 based multi-source simulator. This paper investigates the approach on both multi-junction solar cells and sub-cells.

A Si IV/O IV Electron Density Diagnostic for the Analysis of IRIS Solar Spectra

NASA Astrophysics Data System (ADS)

Young, P. R.; Keenan, F. P.; Milligan, R. O.; Peter, H.

2018-04-01

Solar spectra of ultraviolet bursts and flare ribbons from the Interface Region Imaging Spectrograph (IRIS) have suggested high electron densities of > {10}12 cm‑3 at transition region temperatures of 0.1 MK, based on large intensity ratios of Si IV λ1402.77 to O IV λ1401.16. In this work, a rare observation of the weak O IV λ1343.51 line is reported from an X-class flare that peaked at 21:41 UT on 2014 October 24. This line is used to develop a theoretical prediction of the Si IV λ1402.77 to O IV λ1401.16 ratio as a function of density that is recommended to be used in the high-density regime. The method makes use of new pressure-dependent ionization fractions that take account of the suppression of dielectronic recombination at high densities. It is applied to two sequences of flare kernel observations from the October 24 flare. The first shows densities that vary between 3× {10}12 and 3× {10}13 cm‑3 over a seven-minute period, while the second location shows stable density values of around 2× {10}12 cm‑3 over a three-minute period.

Real-time Series Resistance Monitoring in PV Systems; NREL (National Renewable Energy Laboratory)

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

Deceglie, M. G.; Silverman, T. J.; Marion, B.

We apply the physical principles of a familiar method, suns-Voc, to a new application: the real-time detection of series resistance changes in modules and systems operating outside. The real-time series resistance (RTSR) method that we describe avoids the need for collecting IV curves or constructing full series-resistance-free IV curves. RTSR is most readily deployable at the module level on apply the physical principles of a familiar method, suns-Voc, to a new application: the real-time detection of series resistance changes in modules and systems operating outside. The real-time series resistance (RTSR) method that we describe avoids the need for collecting IVmore » curves or constructing full series-resistance-free IV curves. RTSR is most readily deployable at the module level on micro-inverters or module-integrated electronics, but it can also be extended to full strings. Automated detection of series resistance increases can provide early warnings of some of the most common reliability issues, which also pose fire risks, including broken ribbons, broken solder bonds, and contact problems in the junction or combiner box. We describe the method in detail and describe a sample application to data collected from modules operating in the field.« less

Fabricate heterojunction diode by using the modified spray pyrolysis method to deposit nickel-lithium oxide on indium tin oxide substrate.

PubMed

Wu, Chia-Ching; Yang, Cheng-Fu

2013-06-12

P-type lithium-doped nickel oxide (p-LNiO) thin films were deposited on an n-type indium tin oxide (ITO) glass substrate using the modified spray pyrolysis method (SPM), to fabricate a transparent p-n heterojunction diode. The structural, optical, and electrical properties of the p-LNiO and ITO thin films and the p-LNiO/n-ITO heterojunction diode were characterized by field emission scanning electron microscopy (FE-SEM), X-ray diffraction (XRD), UV-visible spectroscopy, Hall effect measurement, and current-voltage (I-V) measurements. The nonlinear and rectifying I-V properties confirmed that a heterojunction diode characteristic was successfully formed in the p-LNiO/n-ITO (p-n) structure. The I-V characteristic was dominated by space-charge-limited current (SCLC), and the Anderson model demonstrated that band alignment existed in the p-LNiO/n-ITO heterojunction diode.

Segregation and recombination of a multipartite mitochondrial DNA in populations of the potato cyst nematode Globodera pallida.

PubMed

Armstrong, Miles R; Husmeier, Dirk; Phillips, Mark S; Blok, Vivian C

2007-06-01

The discovery that the potato cyst nematode Globodera pallida has a multipartite mitochondrial DNA (mtDNA) composed, at least in part, of six small circular mtDNAs (scmtDNAs) raised a number of questions concerning the population-level processes that might act on such a complex genome. Here we report our observations on the distribution of some scmtDNAs among a sample of European and South American G. pallida populations. The occurrence of sequence variants of scmtDNA IV in population P4A from South America, and that particular sequence variants are common to the individuals within a single cyst, is described. Evidence for recombination of sequence variants of scmtDNA IV in P4A is also reported. The mosaic structure of P4A scmtDNA IV sequences was revealed using several detection methods and recombination breakpoints were independently detected by maximum likelihood and Bayesian MCMC methods.

Risk factors associated with difficult venous access in adult ED patients.

PubMed

Fields, J Matthew; Piela, Nicole E; Au, Arthur K; Ku, Bon S

2014-10-01

The objective was to determine risk factors associated with difficult venous access (DVA) in the emergency department (ED). This was a prospective, observational study conducted in the ED of an urban tertiary care hospital. Adult patients undergoing intravenous (IV) placement were consecutively enrolled during periods of block enrollment. The primary outcome was DVA, defined as 3 or more IV attempts or use of a method of rescue vascular access to establish IV access. Univariate and multivariate analyses for factors predicting DVA were performed using logistic regression. A total of 743 patients were enrolled, of which 88 (11.8%) met the criteria for DVA. In the adjusted analysis, only 3 medical conditions were significantly associated with DVA: diabetes (odds ratio [OR] 1.72, 95% confidence interval [CI] 1.1-2.8), sickle cell disease (OR 3.8, 95% CI 1.5-9.5), and history of IV drug abuse (OR 2.5, 95% CI 1.1-5.7). Notably, age, body mass index, and dialysis were not. Of patients who reported a history of requiring multiple IV attempts in the past for IV access, 14% met criteria for DVA on this visit (OR 7.7 95% CI 3-18). Of the patients who reported a history of IV insertion into the external jugular, ultrasound-guided IV placement, or a central venous catheter for IV access, 26% had DVA on this visit (OR 16.7, 95% CI 6.8-41). Nearly 1 of every 9 to 10 adults in an urban ED had DVA. Diabetes, IV drug abuse, and sickle cell disease were found to be significantly associated with DVA. Copyright © 2014 Elsevier Inc. All rights reserved.

Enteral Contrast in the Computed Tomography Diagnosis of Appendicitis

PubMed Central

Drake, Frederick Thurston; Alfonso, Rafael; Bhargava, Puneet; Cuevas, Carlos; Dighe, Manjiri K.; Florence, Michael G.; Johnson, Morris G.; Jurkovich, Gregory J.; Steele, Scott R.; Symons, Rebecca Gaston; Thirlby, Richard C.; Flum, David R.

2014-01-01

Objective Our goal was to perform a comparative effectiveness study of intravenous (IV)-only versus IV + enteral contrast in computed tomographic (CT) scans performed for patients undergoing appendectomy across a diverse group of hospitals. Background Small randomized trials from tertiary centers suggest that enteral contrast does not improve diagnostic performance of CT for suspected appendicitis, but generalizability has not been demonstrated. Eliminating enteral contrast may improve efficiency, patient comfort, and safety. Methods We analyzed data for adult patients who underwent nonelective appendectomy at 56 hospitals over a 2-year period. Data were obtained directly from patient charts by trained abstractors. Multivariate logistic regression was utilized to adjust for potential confounding. The main outcome measure was concordance between final radiology interpretation and final pathology report. Results A total of 9047 adults underwent appendectomy and 8089 (89.4%) underwent CT, 54.1% of these with IV contrast only and 28.5% with IV + enteral contrast. Pathology findings correlated with radiographic findings in 90.0% of patients who received IV + enteral contrast and 90.4% of patients scanned with IV contrast alone. Hospitals were categorized as rural or urban and by their teaching status. Regardless of hospital type, there was no difference in concordance between IV-only and IV + enteral contrast. After adjusting for age, sex, comorbid conditions, weight, hospital type, and perforation, odds ratio of concordance for IV + enteral contrast versus IV contrast alone was 0.95 (95% CI: 0.72–1.25). Conclusions Enteral contrast does not improve CT evaluation of appendicitis in patients undergoing appendectomy. These broadly generalizable results from a diverse group of hospitals suggest that enteral contrast can be eliminated in CT scans for suspected appendicitis. PMID:24598250

Multiple Intravenous Infusions Phase 2b: Laboratory Study

PubMed Central

Pinkney, Sonia; Fan, Mark; Chan, Katherine; Koczmara, Christine; Colvin, Christopher; Sasangohar, Farzan; Masino, Caterina; Easty, Anthony; Trbovich, Patricia

2014-01-01

Background Administering multiple intravenous (IV) infusions to a single patient via infusion pump occurs routinely in health care, but there has been little empirical research examining the risks associated with this practice or ways to mitigate those risks. Objectives To identify the risks associated with multiple IV infusions and assess the impact of interventions on nurses’ ability to safely administer them. Data Sources and Review Methods Forty nurses completed infusion-related tasks in a simulated adult intensive care unit, with and without interventions (i.e., repeated-measures design). Results Errors were observed in completing common tasks associated with the administration of multiple IV infusions, including the following (all values from baseline, which was current practice): setting up and programming multiple primary continuous IV infusions (e.g., 11.7% programming errors) identifying IV infusions (e.g., 7.7% line-tracing errors) managing dead volume (e.g., 96.0% flush rate errors following IV syringe dose administration) setting up a secondary intermittent IV infusion (e.g., 11.3% secondary clamp errors) administering an IV pump bolus (e.g., 11.5% programming errors) Of 10 interventions tested, 6 (1 practice, 3 technology, and 2 educational) significantly decreased or even eliminated errors compared to baseline. Limitations The simulation of an adult intensive care unit at 1 hospital limited the ability to generalize results. The study results were representative of nurses who received training in the interventions but had little experience using them. The longitudinal effects of the interventions were not studied. Conclusions Administering and managing multiple IV infusions is a complex and risk-prone activity. However, when a patient requires multiple IV infusions, targeted interventions can reduce identified risks. A combination of standardized practice, technology improvements, and targeted education is required. PMID:26316919

What Have We Learned From the Typhoid Fever Surveillance in Africa Program?

PubMed

Baker, Stephen; Hombach, Joachim; Marks, Florian

2016-03-15

The Typhoid Fever Surveillance in Africa Program (TSAP) was established in 2009 to fill the data void concerning invasive Salmonella disease in sub-Saharan Africa, and to specifically estimate the burden of bloodstream infections caused by the key pathogen, Salmonella enterica serovar Typhi. TSAP has achieved this ambitious target, finding high incidences of typhoid fever in both rural and urban populations in several countries in sub-Saharan Africa. The results of TSAP will undoubtedly dictate the direction of future typhoid fever research in Africa, and at last provides a key piece of the disease burden jigsaw puzzle. With the dawn of new Vi conjugate vaccines against Salmonella Typhi, the next priority for the typhoid community must be providing the required data on these vaccines so they can be licensed and provided to those in high-risk groups and locations across sub-Saharan Africa. © The Author 2016. Published by Oxford University Press for the Infectious Diseases Society of America.

Does Prop-2-ynylideneamine, HC≡CCH=NH, Exist in Space? A Theoretical and Computational Investigation

PubMed Central

Osman, Osman I.; Elroby, Shaaban A.; Aziz, Saadullah G.; Hilal, Rifaat H.

2014-01-01

MP2, DFT and CCSD methods with 6-311++G** and aug-cc-pvdz basis sets have been used to probe the structural changes and relative energies of E-prop-2-ynylideneamine (I), Z-prop-2-ynylideneamine (II), prop-1,2-diene-1-imine (III) and vinyl cyanide (IV). The energy near-equivalence and provenance of preference of isomers and tautomers were investigated by NBO calculations using HF and B3LYP methods with 6-311++G** and aug-cc-pvdz basis sets. All substrates have Cs symmetry. The optimized geometries were found to be mainly theoretical method dependent. All elected levels of theory have computed I/II total energy of isomerization (ΔE) of 1.707 to 3.707 kJ/mol in favour of II at 298.15 K. MP2 and CCSD methods have indicated clearly the preference of II over III; while the B3LYP functional predicted nearly similar total energies. All tested levels of theory yielded a global II/IV tautomerization total energy (ΔE) of 137.3–148.4 kJ/mol in support of IV at 298.15 K. The negative values of ΔS indicated that IV is favoured at low temperature. At high temperature, a reverse tautomerization becomes spontaneous and II is preferred. The existence of II in space was debated through the interpretation and analysis of the thermodynamic and kinetic studies of this tautomerization reaction and the presence of similar compounds in the Interstellar Medium (ISM). PMID:24950178

Quantitative analysis of charge trapping and classification of sub-gap states in MoS2 TFT by pulse I-V method

NASA Astrophysics Data System (ADS)

Park, Junghak; Hur, Ji-Hyun; Jeon, Sanghun

2018-04-01

The threshold voltage instabilities and huge hysteresis of MoS2 thin film transistors (TFTs) have raised concerns about their practical applicability in next-generation switching devices. These behaviors are associated with charge trapping, which stems from tunneling to the adjacent trap site, interfacial redox reaction and interface and/or bulk trap states. In this report, we present quantitative analysis on the electron charge trapping mechanism of MoS2 TFT by fast pulse I-V method and the space charge limited current (SCLC) measurement. By adopting the fast pulse I-V method, we were able to obtain effective mobility. In addition, the origin of the trap states was identified by disassembling the sub-gap states into interface trap and bulk trap states by simple extraction analysis. These measurement methods and analyses enable not only quantitative extraction of various traps but also an understanding of the charge transport mechanism in MoS2 TFTs. The fast I-V data and SCLC data obtained under various measurement temperatures and ambient show that electron transport to neighboring trap sites by tunneling is the main charge trapping mechanism in thin-MoS2 TFTs. This implies that interfacial traps account for most of the total sub-gap states while the bulk trap contribution is negligible, at approximately 0.40% and 0.26% in air and vacuum ambient, respectively. Thus, control of the interface trap states is crucial to further improve the performance of devices with thin channels.

Quantitative analysis of charge trapping and classification of sub-gap states in MoS2 TFT by pulse I-V method.

PubMed

Park, Junghak; Hur, Ji-Hyun; Jeon, Sanghun

2018-04-27

The threshold voltage instabilities and huge hysteresis of MoS 2 thin film transistors (TFTs) have raised concerns about their practical applicability in next-generation switching devices. These behaviors are associated with charge trapping, which stems from tunneling to the adjacent trap site, interfacial redox reaction and interface and/or bulk trap states. In this report, we present quantitative analysis on the electron charge trapping mechanism of MoS 2 TFT by fast pulse I-V method and the space charge limited current (SCLC) measurement. By adopting the fast pulse I-V method, we were able to obtain effective mobility. In addition, the origin of the trap states was identified by disassembling the sub-gap states into interface trap and bulk trap states by simple extraction analysis. These measurement methods and analyses enable not only quantitative extraction of various traps but also an understanding of the charge transport mechanism in MoS 2 TFTs. The fast I-V data and SCLC data obtained under various measurement temperatures and ambient show that electron transport to neighboring trap sites by tunneling is the main charge trapping mechanism in thin-MoS 2 TFTs. This implies that interfacial traps account for most of the total sub-gap states while the bulk trap contribution is negligible, at approximately 0.40% and 0.26% in air and vacuum ambient, respectively. Thus, control of the interface trap states is crucial to further improve the performance of devices with thin channels.

An Investigation into the Effect of the Mode of Presentation on Contract Evaluation When Cost/Schedule Control System Criteria Is Used.

DTIC Science & Technology

1986-09-01

inversely related to years of experience. 1 18 IV. Methodology The methods used to test the research hypotheses were experimentation and survey. Two test...17 IV. Methodology .. .. .. .. .. .. .. ... .. ... .. .... 19 Task. .. .. .. .. .. .. ... .. ... .. ... .... 19 Population...Attribute Ratings vs Mode of Presentation (Paired T-test). . 53 XXVI. Preferences ............................... 53 vii Abstract This rsearch -focused

Examining the Stability of "DSM-IV" and Empirically Derived Eating Disorder Classification: Implications for "DSM-5"

ERIC Educational Resources Information Center

Peterson, Carol B.; Crow, Scott J.; Swanson, Sonja A.; Crosby, Ross D.; Wonderlich, Stephen A.; Mitchell, James E.; Agras, W. Stewart; Halmi, Katherine A.

2011-01-01

Objective: The purpose of this investigation was to derive an empirical classification of eating disorder symptoms in a heterogeneous eating disorder sample using latent class analysis (LCA) and to examine the longitudinal stability of these latent classes (LCs) and the stability of DSM-IV eating disorder (ED) diagnoses. Method: A total of 429…

A Brief "DSM-IV"-Referenced Teacher Rating Scale for Monitoring Behavioral Improvement in ADHD and Co-Occurring Symptoms

ERIC Educational Resources Information Center

Sprafkin, Joyce; Mattison, Richard E.; Gadow, Kenneth D.; Schneider, Jayne; Lavigne, John V.

2011-01-01

Objective: To examine the psychometric properties of the 30-item teacher's version of the Child and Adolescent Symptom Inventory Progress Monitor (CASI-PM-T), a "DSM-IV"-referenced rating scale for monitoring change in ADHD and co-occurring symptoms in youths receiving behavioral or pharmacological interventions. Method: Three separate studies…

Prevalence of neuroleptic-induced movement disorders in chronic schizophrenia inpatients.

PubMed

Janno, Sven; Holi, Matti; Tuisku, Katinka; Wahlbeck, Kristian

2004-01-01

Since most of the world's schizophrenia patients are treated with conventional antipsychotics, the authors evaluated various methods for establishing the prevalence of neuroleptic-induced movement disorders in these patients. DSM-IV criteria and established score thresholds on a movement disorder rating scale were used to identify cases of neuroleptic-induced movement disorder in a representative Estonian patient sample of 99 chronic institutionalized schizophrenia patients, 18-65 years old, treated with conventional neuroleptics (79.8%) or clozapine (20.2%). Neuroleptic-induced movement disorders according to DSM-IV criteria were found in 61.6% of the group: 31.3% had neuroleptic-induced akathisia, 23.2% had neuroleptic-induced parkinsonism, and 32.3% had neuroleptic-induced tardive dyskinesia. Prevalence rates for akathisia and tardive dyskinesia were similar when either DSM-IV criteria or rating scale scores were used, but the prevalence rate for parkinsonism was much lower per DSM-IV criteria than according to rating scale score. Nearly two-thirds of chronic schizophrenia patients suffered from a neuroleptic-induced movement disorder. Globally, extrapyramidal adverse effects still impose a huge burden on the majority of neuroleptic-treated individuals with schizophrenia. The discrepancy between the standard identification methods for neuroleptic-induced movement disorder indicate the need for further research.

High performance preconcentration of inorganic Se species by dispersive micro-solid phase extraction with a nanosilica-ionic liquid hybrid material

NASA Astrophysics Data System (ADS)

Llaver, Mauricio; Coronado, Eduardo A.; Wuilloud, Rodolfo G.

2017-12-01

A highly sensitive and efficient dispersive micro-solid phase extraction (D-μ-SPE) method was developed for inorganic Se speciation analysis. A novel ionic liquid (IL)-nanomaterial hybrid consisting of 1-dodecyl-3-methylimidazolium bromide-functionalized nanosilica was used for the efficient retention of Se(IV) complexed with ammonium pyrrolidine dithiocarbamate, followed by elution with an ethyl acetate/Triton X-114 mixture and determination by electrothermal atomic absorption spectroscopy. The Se(VI) species was selectively determined by difference between total inorganic Se and Se(IV) after pre-reduction. The IL-nanomaterial hybrid was characterized by Fourier transform infrared spectroscopy and transmission electronic microscopy. Likewise, Se(IV) sorption capacity of the retention material and maximum amount of IL loaded on its surface were determined. Several factors concerning the functionalization, extraction and elution steps were optimized, yielding a 100% extraction efficiency for Se(IV) under optimal conditions. A limit of detection of 1.1 ng L- 1, a relative standard deviation of 5.7% and a 110-fold enhancement factor were obtained. The D-μ-SPE method was successfully applied to several water samples from different origins and compositions, including rain, tap, underground, river and sea.

Separation, preconcentration and inductively coupled plasma-mass spectrometric (ICP-MS) determination of thorium(IV), titanium(IV), iron(III), lead(II) and chromium(III) on 2-nitroso-1-naphthol impregnated MCI GEL CHP20P resin.

PubMed

Aydin, Funda Armagan; Soylak, Mustafa

2010-01-15

A simple and effective method is presented for the separation and preconcentration of Th(IV), Ti(IV), Fe(III), Pb(II) and Cr(III) by solid phase extraction on 2-nitroso-1-naphthol impregnated MCI GEL CHP20P resin prior to their inductively coupled plasma-mass spectrometric determinations. The influence of analytical parameters including pH of the aqueous solution, flow rates of sample and eluent solutions and sample volume on the quantitative recoveries of analyte ions was investigated. Matrix effects caused by the presence of alkali, earth alkali and some metal ions in the analyzed solutions were investigated. The presented solid phase extraction method was applied to BCR-144R Sewage Sludge (domestic origin), BCR-141R Calcareous Loam Soil, NIST 1568a Rice Flour and NIST 1577b Bovine Liver certified reference materials (CRMs) for the determination of analyte ions and the results were in good agreement with the certified values. The separation procedure presented was also applied to the various natural water samples collected from Turkey with satisfactory results.

Power and instrument strength requirements for Mendelian randomization studies using multiple genetic variants.

PubMed

Pierce, Brandon L; Ahsan, Habibul; Vanderweele, Tyler J

2011-06-01

Mendelian Randomization (MR) studies assess the causality of an exposure-disease association using genetic determinants [i.e. instrumental variables (IVs)] of the exposure. Power and IV strength requirements for MR studies using multiple genetic variants have not been explored. We simulated cohort data sets consisting of a normally distributed disease trait, a normally distributed exposure, which affects this trait and a biallelic genetic variant that affects the exposure. We estimated power to detect an effect of exposure on disease for varying allele frequencies, effect sizes and samples sizes (using two-stage least squares regression on 10,000 data sets-Stage 1 is a regression of exposure on the variant. Stage 2 is a regression of disease on the fitted exposure). Similar analyses were conducted using multiple genetic variants (5, 10, 20) as independent or combined IVs. We assessed IV strength using the first-stage F statistic. Simulations of realistic scenarios indicate that MR studies will require large (n > 1000), often very large (n > 10,000), sample sizes. In many cases, so-called 'weak IV' problems arise when using multiple variants as independent IVs (even with as few as five), resulting in biased effect estimates. Combining genetic factors into fewer IVs results in modest power decreases, but alleviates weak IV problems. Ideal methods for combining genetic factors depend upon knowledge of the genetic architecture underlying the exposure. The feasibility of well-powered, unbiased MR studies will depend upon the amount of variance in the exposure that can be explained by known genetic factors and the 'strength' of the IV set derived from these genetic factors.

35% Good Outcome Rate in IV-tPA treated Patients with CTA Confirmed Severe Anterior Circulation Occlusive Stroke

PubMed Central

González, R. Gilberto; Furie, Karen L.; Goldmacher, Gregory V.; Smith, Wade S.; Kamalian, Shervin; Payabvash, Seyedmehdi; Harris, Gordon J.; Halpern, Elkan F.; Koroshetz, Walter J.; Camargo, Erica C. S.; Dillon, William P.; Lev, Michael H.

2015-01-01

BACKGROUND AND PURPOSE To determine the effect of IV-tPA on outcomes in patients with severe major anterior circulation ischemic stroke. METHODS Prospectively, 649 acute stroke patients had admission NIH stroke scale scores (NIHSS), non-contrast CT, CT angiography (CTA), and 6-month outcome assessed using modified Rankin scale (mRS). IV-tPA treatment decisions were made prior to CTA, at the time of non-contrast CT scanning, as per routine clinical protocol. Severe symptoms were defined as NIHSS>10. Poor outcome was defined as mRS>2. Major occlusions were identified on CTA. Univariate and multivariate stepwise-forward logistic regression analyses of the full cohort were performed. RESULTS Of 649 patients, 188 (29%) presented with NIHSS>10, and 64/188 (34%) of these received IV-tPA. Admission NIHSS, large artery occlusion, and IV-tPA all independently predicted good outcomes, however a significant interaction existed between IV-tPA and occlusion (p<0.001). Of NIHSS>10 patients with anterior circulation occlusion, twice the percentage had good outcomes if they received IV-tPA (17/49, 35%), than if they did not (13/77, 17%; p=0.031). The “number needed to treat” was 7 (95% CI = 3–60). CONCLUSIONS IV-tPA treatment resulted in significantly more good outcomes in severely symptomatic stroke patients with major anterior circulation occlusions. The 35% good outcome rate was similar to rates found in endovascular therapy trials. Vascular imaging may help in patient selection and stratification for trials of IV-thrombolytic and endovascular therapies. PMID:24003051

Method matters: Understanding diagnostic reliability in DSM-IV and DSM-5.

PubMed

Chmielewski, Michael; Clark, Lee Anna; Bagby, R Michael; Watson, David

2015-08-01

Diagnostic reliability is essential for the science and practice of psychology, in part because reliability is necessary for validity. Recently, the DSM-5 field trials documented lower diagnostic reliability than past field trials and the general research literature, resulting in substantial criticism of the DSM-5 diagnostic criteria. Rather than indicating specific problems with DSM-5, however, the field trials may have revealed long-standing diagnostic issues that have been hidden due to a reliance on audio/video recordings for estimating reliability. We estimated the reliability of DSM-IV diagnoses using both the standard audio-recording method and the test-retest method used in the DSM-5 field trials, in which different clinicians conduct separate interviews. Psychiatric patients (N = 339) were diagnosed using the SCID-I/P; 218 were diagnosed a second time by an independent interviewer. Diagnostic reliability using the audio-recording method (N = 49) was "good" to "excellent" (M κ = .80) and comparable to the DSM-IV field trials estimates. Reliability using the test-retest method (N = 218) was "poor" to "fair" (M κ = .47) and similar to DSM-5 field-trials' estimates. Despite low test-retest diagnostic reliability, self-reported symptoms were highly stable. Moreover, there was no association between change in self-report and change in diagnostic status. These results demonstrate the influence of method on estimates of diagnostic reliability. (c) 2015 APA, all rights reserved).

Plutonium Extraction by the Formation of Insoluble Salts; EXTRACTION DU PLUTONIUM PAR FORMATION DE SELS INSOLUBLES

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

Ganivet, M.

1960-06-29

The aim of this work is to convert Pu IV nitrate in solution into an insoluble salt. Three methods have been studied: 1) the conventional oxalic acid method was improved; 2) precipitation with 8-hydroxyquinoline was tried; 3) the hydrogen peroxide method was adapted to the eluates of the ionic resins from Marcoule. The yield from the oxalic process has been increased (loss of Pu in the mother-liquor brought from 200 mg/l to 20 mg/l). The study of Pu IV precipitation by 8-hydroxyquinoline has shown that the yield is excellent (Pu concentration in the mother-liquor less than 5 mg/h), but decontaminationmore » from impurities is nil. Finally, experiments on the precipitation by hydrogen peroxide of Pu IV solutions at the concentrations normally obtained from the anionic resins at Marcoule have given us good yields (Pu concentration in the mother-liquor less than 7 mg/l), and the purification is better than that obtained by oxalic acid (1000 ppm total impurities after a precipitation). (author)« less

Shunt resistance and saturation current determination in CdTe and CIGS solar cells. Part 1: a new theoretical procedure and comparison with other methodologies

NASA Astrophysics Data System (ADS)

Rangel-Kuoppa, Victor-Tapio; Albor-Aguilera, María-de-Lourdes; Hérnandez-Vásquez, César; Flores-Márquez, José-Manuel; González-Trujillo, Miguel-Ángel; Contreras-Puente, Gerardo-Silverio

2018-04-01

A new proposal for the extraction of the shunt resistance (R sh ) and saturation current (I sat ) of a current-voltage (I-V) measurement of a solar cell, within the one-diode model, is given. First, the Cheung method is extended to obtain the series resistance (R s ), the ideality factor (n) and an upper limit for I sat . In this article which is Part 1 of two parts, two procedures are proposed to obtain fitting values for R sh and I sat within some voltage range. These two procedures are used in two simulated I-V curves (one in darkness and the other one under illumination) to recover the known solar cell parameters R sh , R s , n, I sat and the light current I lig and test its accuracy. The method is compared with two different common parameter extraction methods. These three procedures are used and compared in Part 2 in the I-V curves of CdS-CdTe and CIGS-CdS solar cells.

New process for purifying high purity α1-antitrypsin from Cohn Fraction IV by chromatography: A promising method for the better utilization of plasma.

PubMed

Huangfu, Chaoji; Zhang, Jinchao; Ma, Yuyuan; Jia, Junting; Lv, Maomin; Zhao, Xiong; Zhang, Jingang

2017-03-01

α1-antitrypsin (AAT) is a 52kDa serine protease inhibitor that is abundant in plasma. It is synthesized mainly by hepatic cells, and widely used to treat patients with emphysema due to congenital deficiency of AAT. A new isolation method for the purification of AAT from Cohn Fraction IV (Cohn F IV) is described. Cohn F IV is usually discarded as a byproduct from Cohn process. Using Cohn F IV as starting material does not interfere with the production of other plasma proteins and the cost of purification could be reduced greatly. Parameters of each step during purification were optimized, 15% polyethyleneglycol (PEG) concentration and pH 5.2 for PEG precipitation, elution with 0.05M sodium acetate and pH 4.7 for ion-exchange chromatography, and two steps blue sepharose affinity chromatography were chosen for AAT purification. The final protein with purity of 98.17%, specific activity of 3893.29 IU/mg, and yield of 28.35%, was achieved. Western blotting was applied for qualitative identification of final product, which specifically reacted with goat anti-human AAT antibody. LC-ESI-MS/MS was also employed to confirm the final protein. High performance liquid chromatography was used to analyze the composition of purified protein suggesting that pure protein was achieved. The molecular weight of AAT is 51062.77Da which was identified by LC-MS-MS. The manufacturing process described here may make better use of human plasma with Cohn F IV as starting material. The simple process described in this study is simple and inexpensive, it has a potential value for large scale production. Copyright © 2017 Elsevier B.V. All rights reserved.

Self-consistent-field study of conduction through conjugated molecules

NASA Astrophysics Data System (ADS)

Paulsson, Magnus; Stafström, Sven

2001-07-01

Current-voltage (I-V) characteristics of individual molecules connected by metallic leads are studied theoretically. Using the Pariser-Parr-Pople quantum chemical method to model the molecule enables us to include electron-electron interactions in the Hartree approximation. The self-consistent-field method is used to calculate charging together with other properties for the total system under bias. Thereafter the Landauer formula is used to calculate the current from the transmission amplitudes. The most important parameter to understand charging is the position of the chemical potentials of the leads in relation to the molecular levels. At finite bias, the main part of the potential drop is located at the molecule-lead junctions. Also, the potential of the molecule is shown to partially follow the chemical potential closest to the highest occupied molecular orbital (HOMO). Therefore, the resonant tunneling steps in the I-V curves are smoothed giving a I-V resembling a ``Coulomb-gap.'' However, the charge of the molecule is not quantized since the molecule is small with quite strong interactions with the leads. The calculations predict an increase in the current at the bias corresponding to the energy gap of the molecule irrespective of the metals used in the leads. When the bias is increased further, charge is redistributed from the HOMO level to the lowest unoccupied molecular orbital of the molecule. This gives a step in the I-V curves and a corresponding change in the potential profile over the molecule. Calculations were mainly performed on polyene molecules. Molecules asymmetrically coupled to the leads model the I-V curves for molecules contacted by a scanning tunneling microscopy tip. I-V curves for pentapyrrole and another molecule that show negative differential conductance are also analyzed. The charging of these two systems depends on the shape of the molecular wave functions.

A New Method to Assess Asymmetry in Fingerprints Could Be Used as an Early Indicator of Type 2 Diabetes Mellitus.

PubMed

Morris, Molly R; Ludwar, Bjoern Ch; Swingle, Evan; Mamo, Mahelet N; Shubrook, Jay H

2016-07-01

Inexpensive screening tools are needed to identify individuals predisposed to developing diabetes mellitus (DM). Such early identification coupled with an effective intervention could help many people avoid the substantial health costs of this disease. We investigated the hypothesis that fluctuating asymmetry (FA) in fingerprints is an indicator of type 2 diabetes mellitus (T2DM). Participants with T2DM, with T1DM, and without any indication or known family history of diabetes were fingerprinted with a Crossmatch Verifier 320 LC scanner. Asymmetry scores for each finger pair were assessed using both pattern analysis (ridge counts), and a wavelet-based analysis. Both methods for scoring asymmetry predicted risk of T2DM for finger pair IV, controlling for gender and age. AUC scores were significantly greater than the null for pattern asymmetry scores (finger IV AUC = 0.74), and wavelet asymmetry scores for finger pair IV (AUC = 0.73) and finger pair V (AUC = 0.73), for predicting T2DM. In addition, wavelet asymmetry scores for finger pair IV (AUC = 0.80) and finger pair V (AUC = 0.85) significantly predicted risk of T1DM. A diagnostic tool based on FA in the fingerprints of finger pair IV, measured using a wavelet analysis could be developed for predicting risk prior to associated health problems for both T2DM and T1DM. In addition, given that that the prints for fingers IV and V develop during the 14-17 weeks of gestation, we predict that interventions during this time period of pregnancy will be most successful. © 2016 Diabetes Technology Society.

Do DSM-5 Eating Disorder Criteria Overpathologize Normative Eating Patterns among Individuals with Obesity?

PubMed Central

Eddy, Kamryn T.; Murray, Helen B.; Gorman, Mark J.

2014-01-01

Background. DSM-5 revisions have been criticized in the popular press for overpathologizing normative eating patterns—particularly among individuals with obesity. To evaluate the evidence for this and other DSM-5 critiques, we compared the point prevalence and interrater reliability of DSM-IV versus DSM-5 eating disorders (EDs) among adults seeking weight-loss treatment. Method. Clinicians (n = 2) assigned DSM-IV and DSM-5 ED diagnoses to 100 participants via routine clinical interview. Research assessors (n = 3) independently conferred ED diagnoses via Structured Clinical Interview for DSM-IV and a DSM-5 checklist. Results. Research assessors diagnosed a similar proportion of participants with EDs under DSM-IV (29%) versus DSM-5 (32%). DSM-5 research diagnoses included binge eating disorder (9%), bulimia nervosa (2%), subthreshold binge eating disorder (5%), subthreshold bulimia nervosa (2%), purging disorder (1%), night eating syndrome (6%), and other (7%). Interrater reliability between clinicians and research assessors was “substantial” for both DSM-IV (κ = 0.64, 84% agreement) and DSM-5 (κ = 0.63, 83% agreement). Conclusion. DSM-5 ED criteria can be reliably applied in an obesity treatment setting and appear to yield an overall ED point prevalence comparable to DSM-IV. PMID:25057413

Ti(IV) and the Siderophore Desferrioxamine B: A Tight Complex Has Biological and Environmental Implications.

PubMed

Jones, Kayleigh E; Batchler, Kathleen L; Zalouk, Célia; Valentine, Ann M

2017-02-06

The siderophore desferrioxamine B (DFOB) binds Ti(IV) tightly and precludes its hydrolytic precipitation under biologically and environmentally relevant conditions. This interaction of DFOB with Ti(IV) is investigated by using spectro-potentiometric and spectro-photometric titrations, mass spectrometry, isothermal titration calorimetry (ITC), and computational modeling. The data from pH 2-10 suggest two one-proton equilibria among three species, with one species predominating below pH 3.5, a second from pH 3.5 to 8, and a third above pH 8. The latter species is prone to slow hydrolytic precipitation. Electrospray mass spectrometry allowed the detection of [Ti(IV) (HDFOB)] 2+ and [Ti(DFOB)] + ; these species were assigned as the pH < 3.5 and the 3.5 < pH < 8 species, respectively. The stability constant for Ti(IV)-DFOB was determined by using UV/vis-monitored competition with ethylenediaminetetraacetic acid (EDTA). Taking into consideration the available binding constant of Ti(IV) and EDTA, the data reveal values of log β 111 = 41.7, log β 110 = 38.1, and log β 11-1 = 30.1. The former value was supported by ITC, with the transfer of Ti(IV) from EDTA to DFOB determined to be both enthalpically and entropically favorable. Computational methods yielded a model of Ti-DFOB. The physiological and environmental implications of this tight interaction and the potential role of DFOB in solubilizing Ti(IV) are discussed.

Study on photoelectric parameter measurement method of high capacitance solar cell

NASA Astrophysics Data System (ADS)

Zhang, Junchao; Xiong, Limin; Meng, Haifeng; He, Yingwei; Cai, Chuan; Zhang, Bifeng; Li, Xiaohui; Wang, Changshi

2018-01-01

The high efficiency solar cells usually have high capacitance characteristic, so the measurement of their photoelectric performance usually requires long pulse width and long sweep time. The effects of irradiance non-uniformity, probe shielding and spectral mismatch on the IV curve measurement are analyzed experimentally. A compensation method for irradiance loss caused by probe shielding is proposed, and the accurate measurement of the irradiance intensity in the IV curve measurement process of solar cell is realized. Based on the characteristics that the open circuit voltage of solar cell is sensitive to the junction temperature, an accurate measurement method of the temperature of solar cell under continuous irradiation condition is proposed. Finally, a measurement method with the characteristic of high accuracy and wide application range for high capacitance solar cell is presented.

Instrumental variable specifications and assumptions for longitudinal analysis of mental health cost offsets.

PubMed

O'Malley, A James

2012-12-01

Instrumental variables (IVs) enable causal estimates in observational studies to be obtained in the presence of unmeasured confounders. In practice, a diverse range of models and IV specifications can be brought to bear on a problem, particularly with longitudinal data where treatment effects can be estimated for various functions of current and past treatment. However, in practice the empirical consequences of different assumptions are seldom examined, despite the fact that IV analyses make strong assumptions that cannot be conclusively tested by the data. In this paper, we consider several longitudinal models and specifications of IVs. Methods are applied to data from a 7-year study of mental health costs of atypical and conventional antipsychotics whose purpose was to evaluate whether the newer and more expensive atypical antipsychotic medications lead to a reduction in overall mental health costs.

Determination of the oxidation state of uranium in apatite and phosphorite deposits

USGS Publications Warehouse

Clarke, R.S.; Altschuler, Z.S.

1958-01-01

Geological and mineralogical evidence indicate that the uranium present in apatite may proxy for calcium in the mineral structure as U(IV). An experimental investigation was conducted and chemical evidence was obtained that establishes the presence of U(IV) in apatite. The following analytical procedure was developed for the determination of U(IV). Carbonatefluorapatite is dissolved in 1.5 M orthophosphoric acid at a temperature of 5??C or slightly below and fluorapatite is dissolved in cold 1.2 M hydrochloric acid (approximately 5??C) containing 1.5 g of hydroxylamine hydrochloride per 100 ml. Uranium(IV) is precipitated by cupferron using titanium as a carrier. The uranium in the precipitate is separated by use of the ethyl acetate extraction procedure and determined fluorimetrically. The validity and the limitations of the method have been established by spike experiments. ?? 1958.

Evaluation of transport parameters for PVC based polyvinyl alcohol Ce(IV) phosphate composite membrane.

PubMed

Khan, Mohammad Mujahid Ali; Rafiuddin; Inamuddin

2013-05-01

The aim of this study was to investigate the preparation of novel membrane and the characterization of their properties. A new class of polyvinyl chloride (PVC) based polyvinyl alcohol Ce(IV) phosphate composite membrane was successfully prepared by solution casting method. The structural formation was confirmed by X-ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy and morphological studies. The thermal property was investigated by thermogravimetry analysis (TGA) method. The order of surface charge density for various electrolytes was found to be LiCl

Use and Effectiveness of Intraperitoneal Chemotherapy for Treatment of Ovarian Cancer

PubMed Central

Wright, Alexi A.; Cronin, Angel; Milne, Dana E.; Bookman, Michael A.; Burger, Robert A.; Cohn, David E.; Cristea, Mihaela C.; Griggs, Jennifer J.; Keating, Nancy L.; Levenback, Charles F.; Mantia-Smaldone, Gina; Matulonis, Ursula A.; Meyer, Larissa A.; Niland, Joyce C.; Weeks, Jane C.; O'Malley, David M.

2015-01-01

Purpose A 2006 randomized trial demonstrated a 16-month survival benefit with intraperitoneal and intravenous (IP/IV) chemotherapy administered to patients who had ovarian cancer, compared with IV chemotherapy alone, but more treatment-related toxicities. The objective of this study was to examine the use and effectiveness of IP/IV chemotherapy in clinical practice. Patients and Methods Prospective cohort study of 823 women with stage III, optimally cytoreduced ovarian cancer diagnosed at six National Comprehensive Cancer Network institutions. We examined IP/IV chemotherapy use in all patients diagnosed between 2003 and 2012 (N = 823), and overall survival and treatment-related toxicities with Cox regression and logistic regression, respectively, in a propensity score–matched sample (n = 402) of patients diagnosed from 2006 to 2012, excluding trial participants, to minimize selection bias. Results Use of IP/IV chemotherapy increased from 0% to 33% between 2003 and 2006, increased to 50% from 2007 to 2008, and plateaued thereafter. Between 2006 and 2012, adoption of IP/IV chemotherapy varied by institution from 4% to 67% (P < .001) and 43% of patients received modified IP/IV regimens at treatment initiation. In the propensity score–matched sample, IP/IV chemotherapy was associated with significantly improved overall survival (3-year overall survival, 81% v 71%; hazard ratio, 0.68; 95% CI, 0.47 to 0.99), compared with IV chemotherapy, but also more frequent alterations in chemotherapy delivery route (adjusted rates discontinuation or change, 20.4% v 10.0%; adjusted odds ratio, 2.83; 95% CI, 1.47 to 5.47). Conclusion Although the use of IP/IV chemotherapy increased significantly at National Comprehensive Cancer Network centers between 2003 and 2012, fewer than 50% of eligible patients received it. Increasing IP/IV chemotherapy use in clinical practice may be an important and underused strategy to improve ovarian cancer outcomes. PMID:26240233

Method for separating actinides. [Patent application; stripping of Np from organic extractant

DOEpatents

Friedman, H.A.; Toth, L.M.

1980-11-10

An organic solution used for processing spent nuclear reactor fuels is contacted with an aqueous nitric acid solution to strip Np(VI), U(VI), and Pu(IV) from the organic solution into the acid solution. The acid solution is exposed to ultraviolet light, which reduces Np(VI) to Np(V) without reducing U(VI) and Pu(IV). Since the solubility of Np(V) in the organic solution is much lower than that of Np(VI), U(VI), and Pu(IV), a major part of the Np is stripped from the organic solution while leaving most of the U and Pu therein.

Implementing the UCSD PASCAL system on the MODCOMP computer. [deep space network

NASA Technical Reports Server (NTRS)

Wolfe, T.

1980-01-01

The implementation of an interactive software development system (UCSD PASCAL) on the MODCOMP computer is discussed. The development of an interpreter for the MODCOMP II and the MODCOMP IV computers, written in MODCOMP II assembly language, is described. The complete Pascal programming system was run successfully on a MODCOMP II and MODCOMP IV under both the MAX II/III and MAX IV operating systems. The source code for an 8080 microcomputer version of the interpreter was used as the design for the MODCOMP interpreter. A mapping of the functions within the 8080 interpreter into MODCOMP II assembly language was the method used to code the interpreter.

Characterization of the homologs of flerovium with crown ether based extraction chromatography resins: studies in nitric acid

DOE PAGES

Despotopulos, John D.; Kmak, Kelly N.; Gharibyan, Narek; ...

2016-09-17

Eichrom’s Pb resin, a crown-ether-based extraction chromatography resin, was characterized for separation of the flerovium (Fl) homologs, Pb and Sn. Batch uptake of Pb(II) and Sn(IV) radionuclides was determined from an HNO 3 matrix. Pb(II) was strongly retained on the resin at all HNO 3 concentrations, while Sn(IV) showed no uptake. Extraction kinetics for Pb(II) were examined and show suitable uptake on the second time scale. Here, separation methods for the isolation of individual homologs, Pb(II) and Sn(IV), have been established using 2 mL pre-packed vacuum flow Pb resin columns.

Toxicokinetics of Sulfur Mustard and its DNA-Adducts in the Hairless Guinea Pig - DNA-Adducts as a Measure for Epithelial Damage.

DTIC Science & Technology

1996-03-01

guinea pigs for the intravenous (i.v.), respiratory and percutaneous routes. A highly sensitive method for bioanalysis of the intact agent in blood and tissues was developed, involving gas chromatography with mass-spectrometric detection. Deuterated sulfur mustard (D8-SM) is used as the internal standard. 7-SM-guanine is measured with an immuno-slot-blot assay. In this midterm report the first results on the i.v. toxicokinetics of SM and 7-SM-guanine in hairless guinea pigs are presented. The 96-h i.v. LD50 appeared to be 8.2 mg/kg (95% confidence

A Clinical Comparison Study of Attention Deficit/Hyperactivity Disorder (DSM-IV) and Hyperkinetic Disorder (ICD-10) in Indian children and Adolescents

ERIC Educational Resources Information Center

Sitholey, Prabhat; Agarwal, Vivek; Bharti, Vikram

2012-01-01

Aims: To compare the usefulness of DSM IV and ICD-10 DCR criteria in clinic children presenting with the symptoms of inattention and hyperactivity-impulsivity. Methods: 62 children (54 boys and 8 girls) participated in the study. Children were assessed on Kiddie schedule for affective disorders and schizophrenia--present and lifetime version and…

Assessment of Group Preferences and Group Uncertainty for Decision Making

DTIC Science & Technology

1976-06-01

the individ- uals. decision making , group judgments should be preferred to individual judgments if obtaining group judgments costs more. -26- -YI IV... decision making group . IV. A. 3. Aggregation using conjugate distribution. Arvther procedure for combining indivi(jai probability judgments into a group...statisticized group group decision making group judgment subjective probability Delphi method expected utility nominal group 20. ABSTRACT (Continue on

Diagnostic Classification of Eating Disorders in Children and Adolescents: How Does DSM-IV-TR Compare to Empirically-Derived Categories?

ERIC Educational Resources Information Center

Eddy, Kamryn T.; Le Grange, Daniel; Crosby, Ross D.; Hoste, Renee Rienecke; Doyle, Angela Celio; Smyth, Angela; Herzog, David B.

2010-01-01

Objective: The purpose of this study was to empirically derive eating disorder phenotypes in a clinical sample of children and adolescents using latent profile analysis (LPA), and to compare these latent profile (LP) groups to the DSM-IV-TR eating disorder categories. Method: Eating disorder symptom data collected from 401 youth (aged 7 through 19…

Clinical Implications of DSM-IV Subtyping of Bipolar Disorders in Referred Children and Adolescents

ERIC Educational Resources Information Center

Masi, Gabriele; Perugi, Giulio; Millepiedi, Stefania; Mucci, Maria; Pari, Cinzia; Pfanner, Chiara; Berloffa, Stefano; Toni, Cristina

2007-01-01

Objective: According to DSM-IV, bipolar disorders (BDs) include four subtypes, BD I, BD II, cyclothymic disorder, and BD not otherwise specified (NOS). We explore the clinical implications of this subtyping in a naturalistic sample of referred youths with BD I, BD II, and BD-NOS. Method: The sample consisted of 217 patients, 135 males and 82…

An enhanced cerium(IV)-rhodamine 6G chemiluminescence system using guest-host interactions in a lab-on-a-chip platform for estimating the total phenolic content in food samples.

PubMed

Al Haddabi, Buthaina; Al Lawati, Haider A J; Suliman, FakhrEldin O

2016-04-01

Two chemiluminescence-microfluidic (CL-MF) systems, e.g., Ce(IV)-rhodamine B (RB) and Ce(IV)-rhodamine 6G (R6G), for the determination of the total phenolic content in teas and some sweeteners were evaluated. The results indicated that the Ce(IV)-R6G system was more sensitive in comparison to the Ce(IV)-RB CL system. Therefore, a simple (CL-MF) method based on the CL of Ce(IV)-R6G was developed, and the sensitivity, selectivity and stability of this system were evaluated. Selected phenolic compounds (PCs), such as quercetin (QRC), catechin (CAT), rutin (RUT), gallic acid (GA), caffeic acid (CA) and syringic acid (SA), produced analytically useful chemiluminescence signals with low detection limits ranging from 0.35 nmol L(-1) for QRC to 11.31 nmol L(-1) for SA. The mixing sequence and the chip design were crucial, as the sensitivity and reproducibility could be substantially affected by these two factors. In addition, the anionic surfactant (i.e., sodium dodecyl sulfate (SDS)) can significantly enhance the CL signal intensity by as much as 300% for the QRC solution. Spectroscopic studies indicated that the enhancement was due to a strong guest-host interaction between the cationic R6G molecules and the anionic amphiphilic environment. Other parameters that could affect the CL intensities of the PCs were carefully optimized. Finally, the method was successfully applied to tea and sweetener samples. Six different tea samples exhibited total phenolic/antioxidant levels from 7.32 to 13.5 g per 100g of sample with respect to GA. Four different sweetener samples were also analyzed and exhibited total phenolic/antioxidant levels from 500.9 to 3422.9 mg kg(-1) with respect to GA. The method was selective, rapid and sensitive when used to estimate the total phenolic/antioxidant level, and the results were in good agreement with those reported for honey and tea samples. Copyright © 2015 Elsevier B.V. All rights reserved.

Evaluating chemical extraction techniques for the determination of uranium oxidation state in reduced aquifer sediments.

PubMed

Stoliker, Deborah L; Campbell, Kate M; Fox, Patricia M; Singer, David M; Kaviani, Nazila; Carey, Minna; Peck, Nicole E; Bargar, John R; Kent, Douglas B; Davis, James A

2013-08-20

Extraction techniques utilizing high pH and (bi)carbonate concentrations were evaluated for their efficacy in determining the oxidation state of uranium (U) in reduced sediments collected from Rifle, CO. Differences in dissolved concentrations between oxic and anoxic extractions have been proposed as a means to quantify the U(VI) and U(IV) content of sediments. An additional step was added to anoxic extractions using a strong anion exchange resin to separate dissolved U(IV) and U(VI). X-ray spectroscopy showed that U(IV) in the sediments was present as polymerized precipitates similar to uraninite and/or less ordered U(IV), referred to as non-uraninite U(IV) species associated with biomass (NUSAB). Extractions of sediment containing both uraninite and NUSAB displayed higher dissolved uranium concentrations under oxic than anoxic conditions while extractions of sediment dominated by NUSAB resulted in identical dissolved U concentrations. Dissolved U(IV) was rapidly oxidized under anoxic conditions in all experiments. Uraninite reacted minimally under anoxic conditions but thermodynamic calculations show that its propensity to oxidize is sensitive to solution chemistry and sediment mineralogy. A universal method for quantification of U(IV) and U(VI) in sediments has not yet been developed but the chemical extractions, when combined with solid-phase characterization, have a narrow range of applicability for sediments without U(VI).

Evaluating chemical extraction techniques for the determination of uranium oxidation state in reduced aquifer sediments

USGS Publications Warehouse

Stoliker, Deborah L.; Campbell, Kate M.; Fox, Patricia M.; Singer, David M.; Kaviani, Nazila; Carey, Minna; Peck, Nicole E.; Barger, John R.; Kent, Douglas B.; Davis, James A.

2013-01-01

Extraction techniques utilizing high pH and (bi)carbonate concentrations were evaluated for their efficacy in determining the oxidation state of uranium (U) in reduced sediments collected from Rifle, CO. Differences in dissolved concentrations between oxic and anoxic extractions have been proposed as a means to quantify the U(VI) and U(IV) content of sediments. An additional step was added to anoxic extractions using a strong anion exchange resin to separate dissolved U(IV) and U(VI). X-ray spectroscopy showed that U(IV) in the sediments was present as polymerized precipitates similar to uraninite and/or less ordered U(IV), referred to as non-uraninite U(IV) species associated with biomass (NUSAB). Extractions of sediment containing both uraninite and NUSAB displayed higher dissolved uranium concentrations under oxic than anoxic conditions while extractions of sediment dominated by NUSAB resulted in identical dissolved U concentrations. Dissolved U(IV) was rapidly oxidized under anoxic conditions in all experiments. Uraninite reacted minimally under anoxic conditions but thermodynamic calculations show that its propensity to oxidize is sensitive to solution chemistry and sediment mineralogy. A universal method for quantification of U(IV) and U(VI) in sediments has not yet been developed but the chemical extractions, when combined with solid-phase characterization, have a narrow range of applicability for sediments without U(VI).

Comparison of Intravenous/Oral Ciprofloxacin Plus Metronidazole Versus Piperacillin/Tazobactam in the Treatment of Complicated Intraabdominal Infections

PubMed Central

Cohn, Stephen M.; Lipsett, Pamela A.; Buchman, Timothy G.; Cheadle, William G.; Milsom, Jeffery W.; O’Marro, Steven; Yellin, Albert E.; Jungerwirth, Steven; Rochefort, Estela V.; Haverstock, Daniel C.; Kowalsky, Steven F.

2000-01-01

Objective To compare the safety and efficacy of intravenous (IV) ciprofloxacin plus IV metronidazole (CIP+MET) with that of IV piperacillin/tazobactam (PIP/TAZO) in adults with complicated intraabdominal infections, and to compare the efficacy of sequential IV-to-oral CIP+MET therapy with that of the IV CIP-only regimen. Summary Background Data Treatment of intraabdominal infections remains a challenge, mainly because of their polymicrobial etiology and attendant death and complications. Antimicrobial regimens using sequential IV-to-oral therapy may reduce the length of hospital stay. Methods In this multicenter, randomized, double-blind trial involving 459 patients, clinically improved IV-treated patients were switched to oral therapy after 48 hours. Overall clinical response was the primary efficacy measurement. Results A total of 282 patients (151 CIP+MET, 131 PIP/TAZO) were valid for efficacy. Of these patients, 64% CIP+MET and 57% PIP/TAZO patients were considered candidates for oral therapy. Patients had a mean APACHE II score of 9.6. The most common diagnoses were appendicitis (33%), other intraabdominal infection (29%), and abscess (25%). Overall clinical resolution rates were statistically superior for CIP+MET (74%) compared with PIP/TAZO (63%). Corresponding rates in the subgroup suitable for oral therapy were 85% for CIP+MET and 70% for PIP/TAZO. Postsurgical wound infection rates were significantly lower in CIP+MET (11%) versus PIP/TAZO patients (19%). Mean length of stay was 14 days for CIP+MET and 17 days for PIP/TAZO patients. Conclusion CIP+MET, initially administered IV and followed by CIP+MET oral therapy, was clinically more effective than IV PIP/TAZO for the treatment of patients with complicated intraabdominal infections. PMID:10903605

Flow injection for the determination of Se(IV) and Se(VI) by hydride generation atomic absorption spectrometry with microwave oven on-line prereduction of Se(VI) to Se(IV)

NASA Astrophysics Data System (ADS)

Burguera, J. L.; Carrero, P.; Burguera, M.; Rondon, C.; Brunetto, M. R.; Gallignani, M.

1996-12-01

An on-line flow injection system has been developed for the selective determination of Se(IV) and Se(VI) in citric fruit juices and geothermal waters by hydride generation atomic absorption spectrometry with microwave-aided heating prereduction of Se(VI) to Se(IV). The samples and the prereductant solutions (4 mol l -1 HCl for Se(IV) and 12 mol l -1 HCl for Se(VI)) which circulated in a closed-flow circuit were injected by means of a time-based injector. This mixture was displaced by a carrier solution of 1% v/v of hydrochloric acid through a PTFE coil located inside the focused microwave oven and mixed downstream with a borohydride solution to generate the hydride. The linear ranges were 0-120 and 0-100 μg l -1 of Se(IV) and Se(VI), respectively. The detection limits were 1.0 μg l -1 for Se(IV) and 1.5 μg l -1 for Se(VI). The precision (about 2.0-2.5% RSD) and recoveries (96-98% for Se(IV) and 94-98% for Se(VI)) were good. Total selenium values were also obtained by electrothermal atomic absorption spectrometry which agreed with the content of both selenium species. The sample throughput was about 50 measurements per hour. The main advantage of the method is that the selective determination of Se(IV) and Se(VI) in citric fruit juices and geothermal waters is performed in a closed system with a minimum sample manipulation, exposure to the environment, minimum sample waste and operator attention.

Intra-articular versus intravenous tranexamic acid application in total knee arthroplasty: a meta-analysis of randomized controlled trials.

PubMed

Mi, Bobin; Liu, Guohui; Zhou, Wu; Lv, Huijuan; Liu, Yi; Zha, Kun; Wu, Qipeng; Liu, Jing

2017-07-01

The purpose of this meta-analysis was to compare the blood loss and complications of intra-articular (IA) with intravenous (IV) tranexamic acid (TXA) for total knee arthroplasty (TKA). A comprehensive search of studies was conducted to identify related articles in Pubmed, Embase, Cochrane central Register of Controlled Trials, springerLink, OVID and the Research published from January 1980 to September 2016. All studies that compared IA TXA with IV TXA application on TKA were included. Main outcomes of the two methods were collected and analyzed by using Review Manager 5.3. There were 16 randomized controlled trials with 1308 cases met the criteria. Compared with IV TXA, IA TXA had similar blood volume of drainage, hidden blood loss, transfusion rate and complications (P > 0.05). IA TXA had lower total blood loss than IV TXA, and there was significant difference (P < 0.05). Subgroup analysis of total blood loss based on times of IV TXA administration showed that repeat dose of IV TXA had a higher total blood loss and postoperative hemoglobin drop (P < 0.05) than IA TXA. However, single dose of IV TXA had a similar efficacy on total blood loss and postoperative hemoglobin drop (P > 0.05) when compared with IA TXA. Both IA TXA and single dose of IV TXA are effective in reducing total blood loss and postoperative hemoglobin drop without increasing complications of DVT or PE. The current meta-analysis suggests that 1.5 g TXA by IA administration or 1 g TXA by IV administration 10 min before tourniquet deflation is effective and safe in patients undergoing TKA.

Astragaloside-IV Alleviates Heat-Induced Inflammation by Inhibiting Endoplasmic Reticulum Stress and Autophagy.

PubMed

Dong, Zhiwei; Zhou, Jian; Zhang, Ying; Chen, Yajie; Yang, Zichen; Huang, Guangtao; Chen, Yu; Yuan, Zhiqiang; Peng, Yizhi; Cao, Tongtong

2017-01-01

Thermal injury is the main cause of pulmonary disease in stroke after burn and can be life threatening. Heat-induced inflammation is an important factor that triggers a series of induces pathological changes. However, this mechanism underlying heat-induced inflammation in thermal inhalation injury remains unclear. Studies have revealed that astragaloside-IV (AS-IV), a natural compound extracted from Astragalus membranaceus, has protective effects in inflammatory diseases. Here, we investigated whether the protective effects of AS-IV occur because of the suppression of heat-induced endoplasmic reticulum (ER) stress and excessive autophagy Methods: AS-IV was administered to Wistar rats after thermal inhalation injury and 16HBE140-cells were treated with AS-IV. TNF-α, IL-6, and IL-8 levels were determined by ELISA and real-time PCR. ER stress and autophagy were determined by western blot. Autophagic flux was measured by recording the fluorescence emission of the fusion protein mRFP-GFP-LC3 by dynamic live-cell imaging. AS-IV had protective effects against heat-induced reactive oxygen species production and attenuated ER stress. AS IV alleviated heat-induced excessive autophagy in vitro and in vivo. Excessive autophagy was attenuated by the PERK inhibitor GSK2656157 and eIF2α siRNA, suggesting that heat stress-induced autophagy can activate the PERK-eIF2α pathway. Beclin 1 and Atg5 siRNAs inhibited the upregulation of the inflammatory cytokines TNF-α, IL-6, and IL-8 after heat exposure. Thus, AS-IV may attenuate inflammatory responses by disrupting the crosstalk between autophagy and the PERK-eIF2α pathway and may be an ideal agent for treating inflammatory pulmonary diseases. © 2017 The Author(s). Published by S. Karger AG, Basel.

Simultaneous quantification of flavonoids in blood plasma by a high-performance liquid chromatography method after oral administration of Blumea balsamifera leaf extracts in rats.

PubMed

Nessa, Fazilatun; Ismail, Zhari; Mohamed, Nornisah; Karupiah, Sundram

2013-03-01

The leaves of Blumea balsamifera are used as a folk medicine in kidney stone diseases in South-East Asia. Phytochemical investigation revealed leaves contained a number of flavonoids. In view of these, the present work was aimed to quantify and preliminary pharmacokinetic investigation of five flavonoids viz. dihydroquercetin-7,4¢-dimethyl ether (I), dihydroquercetin-4¢-methyl ether (II), 5,7,3¢,5¢-tetrahydroxyflavanone (III), blumeatin (IV) and quercetin (V) in rat plasma following oral administration (0.5g/Kg) of B. balsamifera leaf extract in rats. Quantification was achieved by using a validated, reproducible high-performance liquid chromatographic method. The mean recoveries of I, II, III, IV and V were 90.6, 93.4, 93.5, 91.2 and 90.3% respectively. The limit of quantification was 25 ng/mL for I and IV, 10 ng/mL for II and III and 100 ng/mL for V respectively. The within day and day-to-day precision for all the compounds were < 10%. The validated HPLC method herein was applied for pharmacokinetic studies and the main pharmacokinetic parameters were: t1/2 (hr) 5.8, 4.3, 2.9, 5.7 and 7.3, Cmax (ng/mL) 594.9, 1542.9 1659.9, 208.9 and 3040.4; Tmax (hr) 4.7, 1.0, 1.0, 3.5 and 2.3; AUC0-oo (ng hr/mL) 5040, 5893, 9260, 1064 and 27233 for I, II, III, IV and V respectively. The developed method was suitable for pharmacokinetic studies and this preliminary study also revealed significant absorption after oral dosing in rats.

Functional assessment of a novel COL4A5 splice region variant and immunostaining of plucked hair follicles as an alternative method of diagnosis in X-linked Alport syndrome

PubMed Central

Malone, Andrew F.; Funk, Steven D.; Alhamad, Tarek; Miner, Jeffrey H.

2016-01-01

Introduction Many COL4A5 splice region variants have been described in patients with X-linked Alport syndrome, but few have been confirmed by functional analysis to actually cause defective splicing. We sought to demonstrate that a novel COL4A5 splice region variant in a family with Alport syndrome is pathogenic using functional studies. We also describe an alternative method of diagnosis. Methods We analyzed targeted next-generation sequencing results of an individual with Alport syndrome and confirmed results by Sanger sequencing in family members. A splicing reporter minigene assay was used to examine the variant’s effect on splicing in transfected cells. Plucked hair follicles from patients and controls were examined for collagen IV proteins using immunofluorescence microscopy. Results A novel splice region mutation in COL4A5, c.1780-6T>G, was identified and segregated with disease in this family. This variant caused frequent skipping of exon 25, resulting in a frameshift and truncation of collagen α5(IV) protein. We also developed and validated a new approach to characterize the expression of collagen α5(IV) protein in the basement membranes of plucked hair follicles. We demonstrated reduced collagen α5(IV) protein in affected male and female individuals in this family, supporting frequent failure of normal splicing. Conclusions Differing normal to abnormal transcript ratios in affected individuals carrying splice region variants may contribute to variable disease severity observed in Alport families. Examination of plucked hair follicles in suspected X-linked Alport syndrome patients may offer a less invasive alternative method of diagnosis and serve as a pathogenicity test for COL4A5 variants of uncertain significance. PMID:28013382

[Economic Evaluation of Integrated Care Systems - Scientific Standard Specifications, Challenges, Best Practice Model].

PubMed

Pimperl, A; Schreyögg, J; Rothgang, H; Busse, R; Glaeske, G; Hildebrandt, H

2015-12-01

 Transparency of economic performance of integrated care systems (IV) is a basic requirement for the acceptance and further development of integrated care. Diverse evaluation methods are used but are seldom openly discussed because of the proprietary nature of the different business models. The aim of this article is to develop a generic model for measuring economic performance of IV interventions.  A catalogue of five quality criteria is used to discuss different evaluation methods -(uncontrolled before-after-studies, control group-based approaches, regression models). On this -basis a best practice model is proposed.  A regression model based on the German morbidity-based risk structure equalisation scheme (MorbiRSA) has some benefits in comparison to the other methods mentioned. In particular it requires less resources to be implemented and offers advantages concerning the relia-bility and the transparency of the method (=important for acceptance). Also validity is sound. Although RCTs and - also to a lesser -extent - complex difference-in-difference matching approaches can lead to a higher validity of the results, their feasibility in real life settings is limited due to economic and practical reasons. That is why central criticisms of a MorbiRSA-based model were addressed, adaptions proposed and incorporated in a best practice model: Population-oriented morbidity adjusted margin improvement model (P-DBV(MRSA)).  The P-DBV(MRSA) approach may be used as a standardised best practice model for the economic evaluation of IV. Parallel to the proposed approach for measuring economic performance a balanced, quality-oriented performance measurement system should be introduced. This should prevent incentivising IV-players to undertake short-term cost cutting at the expense of quality. © Georg Thieme Verlag KG Stuttgart · New York.

Flow injection chemiluminescence determination of the total phenolics levels in plant-derived beverages using soluble manganese(IV).

PubMed

Nalewajko-Sieliwoniuk, Edyta; Tarasewicz, Iwona; Kojło, Anatol

2010-05-23

This study established a flow injection (FI) methodology for the determination of the total phenolic content in plant-derived beverages based on soluble manganese(IV) chemiluminescence (CL) detection. It was found that mixing polyphenols with acidic soluble manganese(IV) in the presence of formaldehyde evoked chemiluminescence. Based on this finding, a new FI-CL method was developed for the estimation of the total content of phenolic compounds (expressed as milligrams of gallic acid equivalent per litre of drink) in a variety of wine, tea and fruit juice samples. The proposed method is sensitive with a detection limit of 0.02 ng mL(-1) (gallic acid), offers a wide linear dynamic range (0.5-400 ng mL(-1)) and high sample throughput (247 samples h(-1)). The relative standard deviation for 15 measurements was 3.8% for 2 ng mL(-1) and 0.45% for 10 ng mL(-1) of gallic acid. Analysis of 36 different samples showed that the results obtained by the proposed FI-CL method correlate highly with those obtained by spectrophotometric methods commonly used for the evaluation of the total phenolic/antioxidant level. However, the FI-CL method was found to be far simpler, more rapid and selective, with almost no interference from non-phenolic components of the samples examined. Copyright 2010 Elsevier B.V. All rights reserved.

48 CFR 15.203 - Requests for proposals.

Code of Federal Regulations, 2010 CFR

2010-10-01

... information regarding cost comparisons between Government and contractor performance. (c) Electronic commerce... RFP shall specify the electronic commerce method(s) that offerors may use (see subpart 4.5). (d... and suitability of electronic commerce methods; and (iv) Adequacy of administrative procedures and...

Chemiluminescence of the reaction system Ce(IV)-non-steroidal anti-inflammatory drugs containing europium(III) ions and its application to the determination of naproxen in pharmaceutical preparations and urine.

PubMed

Kaczmarek, Małgorzata

2011-11-01

The chemiluminescence (CL) of oxidation of non-steroidal anti-inflammatory drugs (NSAIDs) by Ce(IV) ions, was recorded in the presence and absence europium(III) ions, in solution of pH ~ 4 of solution. Kinetic curves and CL emission spectra of the all studied systems were discussed. CL of measurable intensity was observed in the Ce(IV)-NP-Eu(III) reaction system only in acidic solutions. The CL spectrum rcegistered for this system shows emission bands, typical of Eu(III) ions, with maximum at λ ~ 600 nm. The chemiluminescent method, based on Eu(III) emission in reaction system of NP-Ce(IV)-Eu(III) in acid solution was therefore used for the determination of naproxen in mixture of non-steroidal anti-inflammatory drugs.

Speciation of selenium and arsenic compounds by capillary electrophoresis with hydrodynamically modified electroosmotic flow and on-line reduction of selenium(VI) to selenium(IV) with hydride generation inductively coupled plasma mass spectrometric detection.

PubMed

Magnuson, M L; Creed, J T; Brockhoff, C A

1997-10-01

Capillary electrophoresis (CE) with hydride generation inductively coupled plasma mass spectrometry was used to determine four arsenicals and two selenium species. Selenate (SeVI) was reduced on-line to selenite (SeIV) by mixing the CE effluent with concentrated HCl. A microporous PTFE tube was used as a gas-liquid separator to eliminate the 40Ar37Cl and 40Ar35Cl interference from 77Se and 75As, respectively. The direction of the electroosmotic flow during CE was reversed with hydrodynamic pressure, which allowed increased freedom of buffer choice. For conventional pressure injection, method detection limits for SeIV and SeVI based on seven replicate injections were 10 and 24 pg, respectively. Recoveries of SeIV and SeVI in drinking water were measured.

Carbon–hydrogen (C–H) bond activation at PdIV: a Frontier in C–H functionalization catalysis

PubMed Central

Topczewski, Joseph J.

2015-01-01

The direct functionalization of carbon–hydrogen (C–H) bonds has emerged as a versatile strategy for the synthesis and derivatization of organic molecules. Among the methods for C–H bond activation, catalytic processes that utilize a PdII/PdIV redox cycle are increasingly common. The C–H activation step in most of these catalytic cycles is thought to occur at a PdII centre. However, a number of recent reports have suggested the feasibility of C–H cleavage occurring at PdIV complexes. Importantly, these latter processes often result in complementary reactivity and selectivity relative to analogous transformations at PdII. This mini review highlights proposed examples of C–H activation at PdIV centres. Applications of this transformation in catalysis as well as mechanistic details obtained from stoichiometric model studies are discussed. Furthermore, challenges and future perspectives for the field are reviewed. PMID:25544882

Carbon-Hydrogen (C-H) Bond Activation at PdIV: A Frontier in C-H Functionalization Catalysis.

PubMed

Topczewski, Joseph J; Sanford, Melanie S

2015-01-01

The direct functionalization of carbon-hydrogen (C-H) bonds has emerged as a versatile strategy for the synthesis and derivatization of organic molecules. Among the methods for C-H bond activation, catalytic processes that utilize a Pd II /Pd IV redox cycle are increasingly common. The C-H activation step in most of these catalytic cycles is thought to occur at a Pd II centre. However, a number of recent reports have suggested the feasibility of C-H cleavage occurring at Pd IV complexes. Importantly, these latter processes often result in complementary reactivity and selectivity relative to analogous transformations at Pd II . This Mini Review highlights proposed examples of C-H activation at Pd IV centres. Applications of this transformation in catalysis as well as mechanistic details obtained from stoichiometric model studies are discussed. Furthermore, challenges and future perspectives for the field are reviewed.

Spray Drying as a Reliable Route to Produce Metastable Carbamazepine Form IV.

PubMed

Halliwell, Rebecca A; Bhardwaj, Rajni M; Brown, Cameron J; Briggs, Naomi E B; Dunn, Jaclyn; Robertson, John; Nordon, Alison; Florence, Alastair J

2017-07-01

Carbamazepine (CBZ) is an active pharmaceutical ingredient used in the treatment of epilepsy that can form at least 5 polymorphic forms. Metastable form IV was originally discovered from crystallization with polymer additives; however, it has not been observed from subsequent solvent-only crystallization efforts. This work reports the reproducible formation of phase pure crystalline form IV by spray drying of methanolic CBZ solution. Characterization of the material was carried out using diffraction, scanning electron microscopy, and differential scanning calorimetry. In situ Raman spectroscopy was used to monitor the spray-dried product during the spray drying process. This work demonstrates that spray drying provides a robust method for the production of form IV CBZ, and the combination of high supersaturation and rapid solid isolation from solution overcomes the apparent limitation of more traditional solution crystallization approaches to produce metastable crystalline forms. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.

Seeing High Velocity Clouds and Turbulent Mixing Layers in the Ultraviolet: Predictions from Hydrodynamic Simulations

NASA Astrophysics Data System (ADS)

Shelton, Robin L.

2018-06-01

High velocity clouds (HVCs) and turbulent mixing layers (TMLs) emit light across a wide range of wavelengths. In order to aid in the detection of their ultraviolet emission, we predict the UV emission line intensities emitted by C II, C III, C IV, N II, N III, N IV, N V, O III, O IV, O V, O VI, Si II, Si III, and Si IV in a variety of simulated HVCs and TMLs. These predictions are based on detailed hydrodynamic simulations made with the FLASH code and employing non-equilibrium ionization calculations for carbon, nitrogen, oxygen, and silicon. The results are compared with FUSE and SPEAR/FIMS observations and with predictions from other models of hot/cool interfaces. We also present methods for scaling the results so that they can be applied to more or less dense environments.

7 CFR 52.3185 - Moisture limits.

Code of Federal Regulations, 2011 CFR

2011-01-01

... Method or in accordance with methods that give equivalent results. The moisture limits in Table IV apply only to so-called “bulk packs” of dried prunes packaged in non-hermetically sealed containers holding...

Predictive power of the DASA-IV: Variations in rating method and timescales.

PubMed

Nqwaku, Mphindisi; Draycott, Simon; Aldridge-Waddon, Luke; Bush, Emma-Louise; Tsirimokou, Alexandra; Jones, Dominic; Puzzo, Ignazio

2018-05-10

This project evaluated the predictive validity of the Dynamic Appraisal of Situational Aggression - Inpatient Version (DASA-IV) in a high-secure psychiatric hospital in the UK over 24 hours and over a single nursing shift. DASA-IV scores from three sequential nursing shifts over a 24-hour period were compared with the mean (average of three scores across the 24-hour period) and peak (highest of the three scores across the 24-hour period) scores across these shifts. In addition, scores from a single nursing shift were used to predict aggressive incidents over each of the following three shifts. The DASA-IV was completed by nursing staff during handover meetings, rating 43 male psychiatric inpatients over a period of 6 months. Data were compared to incident reports recorded over the same period. Receiver operating characteristic (ROC) curves and generalized estimating equations assessed the predictive ability of various DASA-IV scores over 24-hour and single-shift timescales. Scores from the DASA-IV based on a single shift had moderate predictive ability for aggressive incidents occurring the next calendar day, whereas scores based on all three shifts had excellent predictive ability. DASA-IV scores from a single shift showed moderate predictive ability for each of the following three shifts. The DASA-IV has excellent predictive ability for aggressive incidents within a secure setting when data are summarized over a 24-hour period, as opposed to when a single rating is taken. In addition, it has moderate value for predicting incidents over even shorter timescales. © 2018 Australian College of Mental Health Nurses Inc.

The Effect of Basis Selection on Thermal-Acoustic Random Response Prediction Using Nonlinear Modal Simulation

NASA Technical Reports Server (NTRS)

Rizzi, Stephen A.; Przekop, Adam

2004-01-01

The goal of this investigation is to further develop nonlinear modal numerical simulation methods for prediction of geometrically nonlinear response due to combined thermal-acoustic loadings. As with any such method, the accuracy of the solution is dictated by the selection of the modal basis, through which the nonlinear modal stiffness is determined. In this study, a suite of available bases are considered including (i) bending modes only; (ii) coupled bending and companion modes; (iii) uncoupled bending and companion modes; and (iv) bending and membrane modes. Comparison of these solutions with numerical simulation in physical degrees-of-freedom indicates that inclusion of any membrane mode variants (ii - iv) in the basis affects the bending displacement and stress response predictions. The most significant effect is on the membrane displacement, where it is shown that only the type (iv) basis accurately predicts its behavior. Results are presented for beam and plate structures in the thermally pre-buckled regime.

Ultrafast current imaging by Bayesian inversion

DOE Data Explorer

Somnath, Suhas; Law, Kody J. H.; Morozovska, Anna; Maksymovych, Petro; Kim, Yunseok; Lu, Xiaoli; Alexe, Marin; Archibald, Richard K; Kalinin, Sergei V; Jesse, Stephen; Vasudevan, Rama K

2016-01-01

Spectroscopic measurements of current-voltage curves in scanning probe microscopy is the earliest and one of the most common methods for characterizing local energy-dependent electronic properties, providing insight into superconductive, semiconductor, and memristive behaviors. However, the quasistatic nature of these measurements renders them extremely slow. Here, we demonstrate a fundamentally new approach for dynamic spectroscopic current imaging via full information capture and Bayesian inference analysis. This "general-mode I-V"method allows three orders of magnitude faster rates than presently possible. The technique is demonstrated by acquiring I-V curves in ferroelectric nanocapacitors, yielding >100,000 I-V curves in <20 minutes. This allows detection of switching currents in the nanoscale capacitors, as well as determination of dielectric constant. These experiments show the potential for the use of full information capture and Bayesian inference towards extracting physics from rapid I-V measurements, and can be used for transport measurements in both atomic force and scanning tunneling microscopy. The data was analyzed using pycroscopy - an open-source python package available at https://github.com/pycroscopy/pycroscopy

Nitrogen plasma-treated multilayer graphene-based field effect transistor fabrication and electronic characteristics

NASA Astrophysics Data System (ADS)

Su, Wei-Jhih; Chang, Hsuan-Chen; Honda, Shin-ichi; Lin, Pao-Hung; Huang, Ying-Sheng; Lee, Kuei-Yi

2017-08-01

Chemical doping with hetero-atoms is an effective method used to change the characteristics of materials. Nitrogen doping technology plays a critical role in regulating the electronic properties of graphene. Nitrogen plasma treatment was used in this work to dope nitrogen atoms to modulate multilayer graphene electrical properties. The measured I-V multilayer graphene-base field-effect transistor characteristics (GFETs) showed a V-shaped transfer curve with the hole and electron region separated from the measured current-voltage (I-V) minimum. GFETs fabricated with multilayer graphene from chemical vapor deposition (CVD) exhibited p-type behavior because of oxygen adsorption. After using different nitrogen plasma treatment times, the minimum in I-V characteristic shifted into the negative gate voltage region with increased nitrogen concentration and the GFET channel became an n-type semiconductor. GFETs could be easily fabricated using this method with potential for various applications. The GFET transfer characteristics could be tuned precisely by adjusting the nitrogen plasma treatment time.

Effects of practice on the Wechsler Adult Intelligence Scale-IV across 3- and 6-month intervals.

PubMed

Estevis, Eduardo; Basso, Michael R; Combs, Dennis

2012-01-01

A total of 54 participants (age M = 20.9; education M = 14.9; initial Full Scale IQ M = 111.6) were administered the Wechsler Adult Intelligence Scale-Fourth Edition (WAIS-IV) at baseline and again either 3 or 6 months later. Scores on the Full Scale IQ, Verbal Comprehension, Working Memory, Perceptual Reasoning, Processing Speed, and General Ability Indices improved approximately 7, 5, 4, 5, 9, and 6 points, respectively, and increases were similar regardless of whether the re-examination occurred over 3- or 6-month intervals. Reliable change indices (RCI) were computed using the simple difference and bivariate regression methods, providing estimated base rates of change across time. The regression method provided more accurate estimates of reliable change than did the simple difference between baseline and follow-up scores. These findings suggest that prior exposure to the WAIS-IV results in significant score increments. These gains reflect practice effects instead of genuine intellectual changes, which may lead to errors in clinical judgment.

The 10/66 Dementia Research Group's fully operationalised DSM-IV dementia computerized diagnostic algorithm, compared with the 10/66 dementia algorithm and a clinician diagnosis: a population validation study

PubMed Central

Prince, Martin J; de Rodriguez, Juan Llibre; Noriega, L; Lopez, A; Acosta, Daisy; Albanese, Emiliano; Arizaga, Raul; Copeland, John RM; Dewey, Michael; Ferri, Cleusa P; Guerra, Mariella; Huang, Yueqin; Jacob, KS; Krishnamoorthy, ES; McKeigue, Paul; Sousa, Renata; Stewart, Robert J; Salas, Aquiles; Sosa, Ana Luisa; Uwakwa, Richard

2008-01-01

Background The criterion for dementia implicit in DSM-IV is widely used in research but not fully operationalised. The 10/66 Dementia Research Group sought to do this using assessments from their one phase dementia diagnostic research interview, and to validate the resulting algorithm in a population-based study in Cuba. Methods The criterion was operationalised as a computerised algorithm, applying clinical principles, based upon the 10/66 cognitive tests, clinical interview and informant reports; the Community Screening Instrument for Dementia, the CERAD 10 word list learning and animal naming tests, the Geriatric Mental State, and the History and Aetiology Schedule – Dementia Diagnosis and Subtype. This was validated in Cuba against a local clinician DSM-IV diagnosis and the 10/66 dementia diagnosis (originally calibrated probabilistically against clinician DSM-IV diagnoses in the 10/66 pilot study). Results The DSM-IV sub-criteria were plausibly distributed among clinically diagnosed dementia cases and controls. The clinician diagnoses agreed better with 10/66 dementia diagnosis than with the more conservative computerized DSM-IV algorithm. The DSM-IV algorithm was particularly likely to miss less severe dementia cases. Those with a 10/66 dementia diagnosis who did not meet the DSM-IV criterion were less cognitively and functionally impaired compared with the DSMIV confirmed cases, but still grossly impaired compared with those free of dementia. Conclusion The DSM-IV criterion, strictly applied, defines a narrow category of unambiguous dementia characterized by marked impairment. It may be specific but incompletely sensitive to clinically relevant cases. The 10/66 dementia diagnosis defines a broader category that may be more sensitive, identifying genuine cases beyond those defined by our DSM-IV algorithm, with relevance to the estimation of the population burden of this disorder. PMID:18577205

MoDOT pavement preservation research program volume IV, pavement evaluation tools-data collection methods.

DOT National Transportation Integrated Search

2015-10-01

The overarching goal of the MoDOT Pavement Preservation Research Program, Task 3: Pavement Evaluation Tools Data : Collection Methods was to identify and evaluate methods to rapidly obtain network-level and project-level information relevant to :...

An Introduction to Biological NMR Spectroscopy*

PubMed Central

Marion, Dominique

2013-01-01

NMR spectroscopy is a powerful tool for biologists interested in the structure, dynamics, and interactions of biological macromolecules. This review aims at presenting in an accessible manner the requirements and limitations of this technique. As an introduction, the history of NMR will highlight how the method evolved from physics to chemistry and finally to biology over several decades. We then introduce the NMR spectral parameters used in structural biology, namely the chemical shift, the J-coupling, nuclear Overhauser effects, and residual dipolar couplings. Resonance assignment, the required step for any further NMR study, bears a resemblance to jigsaw puzzle strategy. The NMR spectral parameters are then converted into angle and distances and used as input using restrained molecular dynamics to compute a bundle of structures. When interpreting a NMR-derived structure, the biologist has to judge its quality on the basis of the statistics provided. When the 3D structure is a priori known by other means, the molecular interaction with a partner can be mapped by NMR: information on the binding interface as well as on kinetic and thermodynamic constants can be gathered. NMR is suitable to monitor, over a wide range of frequencies, protein fluctuations that play a crucial role in their biological function. In the last section of this review, intrinsically disordered proteins, which have escaped the attention of classical structural biology, are discussed in the perspective of NMR, one of the rare available techniques able to describe structural ensembles. This Tutorial is part of the International Proteomics Tutorial Programme (IPTP 16 MCP). PMID:23831612

A Volcano Exploration Project Pu`u `O`o (VEPP) Exercise: Is Kilauea in Volcanic Unrest? (Invited)

NASA Astrophysics Data System (ADS)

Schwartz, S. Y.

2010-12-01

Volcanic activity captures the interest and imagination of students at all stages in their education. Analysis of real data collected on active volcanoes can further serve to engage students in higher-level inquiry into the complicated physical processes associated with volcanic eruptions. This exercise takes advantage of both student fascination with volcanoes and the recognized benefits of incorporating real, internet-accessible data to achieve its goals of enabling students to: 1) navigate a scientific website; 2) describe the physical events that produce volcano monitoring data; 3) identify patterns in geophysical time-series and distinguish anomalies preceding and synchronous with eruptive events; 4) compare and contrast geophysical time series and 5) integrate diverse data sets to assess the eruptive state of Kilauea volcano. All data come from the VEPP website (vepp.wr.usgs.gov) which provides background information on the historic activity and volcano monitoring methods as well as near-real time volcano monitoring data from the Pu`u `O`o eruptive vent on Kilauea Volcano. This exercise, designed for geology majors, has students initially work individually to acquire basic skills with volcano monitoring data interpretation and then together in a jigsaw activity to unravel the events leading up to and culminating in the July 2007 volcanic episode. Based on patterns established prior to the July 2007 event, students examine real-time volcano monitoring data to evaluate the present activity level of Kilauea volcano. This exercise will be used for the first time in an upper division Geologic Hazards class in fall 2010 and lessons learned including an exercise assessment will be presented.

Instrumental variable approaches to identifying the causal effect of educational attainment on dementia risk

PubMed Central

Nguyen, Thu T.; Tchetgen Tchetgen, Eric J.; Kawachi, Ichiro; Gilman, Stephen E.; Walter, Stefan; Liu, Sze Y.; Manly, Jennifer; Glymour, M. Maria

2015-01-01

Purpose Education is an established correlate of cognitive status in older adulthood, but whether expanding educational opportunities would improve cognitive functioning remains unclear given limitations of prior studies for causal inference. Therefore, we conducted instrumental variable (IV) analyses of the association between education and dementia risk, using for the first time in this area, genetic variants as instruments as well as state-level school policies. Methods IV analyses in the Health and Retirement Study cohort (1998–2010) used two sets of instruments: 1) a genetic risk score constructed from three single nucleotide polymorphisms (SNPs) (n=8,054); and 2) compulsory schooling laws (CSLs) and state school characteristics (term length, student teacher ratios, and expenditures) (n=13,167). Results Employing the genetic risk score as an IV, there was a 1.1% reduction in dementia risk per year of schooling (95% CI: −2.4, 0.02). Leveraging compulsory schooling laws and state school characteristics as IVs, there was a substantially larger protective effect (−9.5%; 95% CI: −14.8, −4.2). Analyses evaluating the plausibility of the IV assumptions indicated estimates derived from analyses relying on CSLs provide the best estimates of the causal effect of education. Conclusion IV analyses suggest education is protective against risk of dementia in older adulthood. PMID:26633592

IVGEN

NASA Technical Reports Server (NTRS)

DeVon, Griffin; McKay, Terri; McQuillen, John

2011-01-01

The Exploration Medical Capabilities Element of NASA's Human Research Program chartered the IV fluid GENeration (IVGEN) project at the NASA Glenn Research Center to develop a system that could produce IV fluid in a microgravity environment meeting USP standards. NASA's flight surgeons have identified medical conditions likely to arise during exploration missions of various length and distance from the earth. Adequately treating some of those conditions will require the ability to utilize Intravenous (IV) therapy to either serve as a method for delivering pharmaceuticals that can only be administered via that route, or to hydrate patients that are unable to hydrate themselves. Given that need, NASA currently maintains a reserve of IV fluid on ISS sufficient to treat an astronaut until they can be returned to earth, which is generally within 24 hours. Because such a rapid return will not be an designed to produce United States Pharmacopeia ( USP) grade IV fluid in a reduced gravity p option for missions extending beyond low earth orbit, NASA must either fly as many as 100 liters of IV fluid, with a total mass of 100 Kg, or provide systems that can use vehicle resources to produce such fluid if it is needed. The IVGEN hardware, a compact water purification and mixing system, was environment using available resources.

Wechsler Intelligence Scale for Children 4th edition-Chinese version index scores in Taiwanese children with attention-deficit/hyperactivity disorder.

PubMed

Yang, Pinchen; Cheng, Chung-Ping; Chang, Chen-Lin; Liu, Tai-Ling; Hsu, Hsiu-Yi; Yen, Cheng-Fang

2013-02-01

The Wechsler Intelligence Scale for Children 4th edition-Chinese version (WISC-IV-Chinese) has been in clinical use in Taiwan since 2007. Research is needed to determine how the WISC-IV, modified from its earlier version, will affect its interpretation in clinical practice in a Mandarin-speaking context. We attempted to use WISC-IV-Chinese scores to identify the cognitive strengths and weaknesses in 334 Taiwanese children with attention-deficit/hyperactivity disorder (ADHD). Comparison of cognitive profiles of WISC-IV-Chinese scores between subtypes of ADHD was also performed. The results indicated that the four-factor model of the WISC-IV-Chinese fitted well for Taiwanese children with ADHD. The profiles showed that performance in the index score of the Processing Speed Index was the weakness domain for the Taiwanese children with ADHD, as confirmed by two different kinds of analytic methods. Cognitive profile analysis of ADHD subtypes revealed children with inattentive subtypes to have a greater weakness in processing speed performance. The implications of the profiles of the index scores on the WISC-IV-Chinese version for Taiwanese children with ADHD were explored. © 2013 The Authors. Psychiatry and Clinical Neurosciences © 2013 Japanese Society of Psychiatry and Neurology.

The Activity of Class I-IV Alcohol Dehydrogenase Isoenzymes and Aldehyde Dehydrogenase in Bladder Cancer Cells.

PubMed

Orywal, Karolina; Jelski, Wojciech; Werel, Tadeusz; Szmitkowski, Maciej

2018-01-02

The aim of this study was to determine the differences in the activity of Alcohol Dehydrogenase (ADH) isoenzymes and Aldehyde Dehydrogenase (ALDH) in normal and cancerous bladder cells. Class III, IV of ADH and total ADH activity were measured by the photometric method and class I, II ADH and ALDH activity by the fluorometric method. Significantly higher total activity of ADH was found in both, low-grade and high-grade bladder cancer, in comparison to healthy tissues. The increased activity of total ADH in bladder cancer cells may be the cause of metabolic disorders in cancer cells, which may intensify carcinogenesis.

Method for selectively reducing plutonium values by a photochemical process

DOEpatents

Friedman, Horace A.; Toth, Louis M.; Bell, Jimmy T.

1978-01-01

The rate of reduction of Pu(IV) to Pu(III) in nitric acid solution containing a reducing agent is enhanced by exposing the solution to 200-500 nm electromagnetic radiation. Pu values are recovered from an organic extractant solution containing Pu(IV) values and U(VI) values by the method of contacting the extractant solution with an aqueous nitric acid solution in the presence of a reducing agent and exposing the aqueous solution to electromagnetic radiation having a wavelength of 200-500 nm. Under these conditions, Pu values preferentially distribute to the aqueous phase and U values preferentially distribute to the organic phase.

Pedagogies in Action: A Community Resource Linking Teaching Methods to Examples of their Use

NASA Astrophysics Data System (ADS)

Manduca, C. A.; Fox, S. P.; Iverson, E. A.; Kirk, K.; Ormand, C. J.

2009-12-01

The Pedagogies in Action portal (http://serc.carleton.edu/sp) provides access to information on more than 40 teaching methods with examples of their use in geoscience and beyond. Each method is described with pages addressing what the method is, why or when it is useful, and how it can be implemented. New methods added this year include Teaching with Google Earth, Jigsaw, Teaching the Process of Science, Guided Discovery Problems, Teaching Urban Students, and Using ConceptTests. Examples then show specifically how the method has been used to teach concepts in a variety of disciplines. The example collection now includes 775 teaching activities of which more than 550 are drawn from the geosciences. Geoscience faculty are invited to add their own examples to this collection or to test examples in the collection and provide a review. Evaluation results show that the combination of modules and activities inspires teachers at all levels to use a new pedagogy and increases their confidence that they can use it successfully. In addition, submitting activities to the collection, including writing summary information for other instructors, helps them think more carefully about the design of their activity. The activity collections are used both for ready to use activities and to find ideas for new activities. The portal provides overarching access to materials developed by a wide variety of collaborating partners each of which uses the service to create a customized pedagogic portal addressing a more specific audience. Of interest to AGU members are pedagogic portals on Starting Point: Teaching Introductory Geoscience (http://serc.carleton.edu/introgeo); On the Cutting Edge (http://serc.carleton.edu/NAGTWorkshops); Enduring Resources for Earth System Education (http://earthref.org/ERESE) Microbial Life Educational Resources (http://serc.carleton.edu/microbe_life); the National Numeracy Network (http://serc.carleton.edu/nnn/index.html); CAUSE: The Consortium for Undergraduate Statistics Education (http://causeweb.org); ComPADRE: Digital Resources for Physics and Astronomy Education (http://www.compadre.org) and Project Kaleidoscope (http://pkal.org). Pedagogies in Action is part of the National Science Digital Library (http://nsdl.org). Projects or groups interested in exploring use of the service can find information about using the service on the project website or contact the authors.

Determination of sub-ng g-1 levels of total inorganic arsenic and selenium in foods by hydride-generation atomic absorption spectrometry after pre-concentration.

PubMed

Altunay, Nail; Gürkan, Ramazan

2017-03-01

A new and simple ultrasonic-assisted extraction (UAE) procedure was developed for the determination of inorganic arsenic and selenium in foods by hydride-generation atomic absorption spectrometry (HG-AAS). The various analytical variables affecting complex formation and extraction efficiency were investigated and optimised. The method is based on selective complex formation of As(III) and Se(IV) in the presence of excess As(V) and Se(VI) with toluidine red in the presence of tartaric acid at pH 4.5, and then extraction of the resulting condensation products into the micellar phase of non-ionic surfactant, polyethylene glycol dodecyl ether, Brij 35. Under optimised conditions, good linear relationships were obtained in the ranges of 4-225 and 12-400 ng l - 1 with limits of detection of 1.1 and 3.5 ng l - 1 for As(III) and Se(IV), respectively. The repeatability was better than 3.9% for both analytes (n = 10, 25 ng l - 1 ) while reproducibility ranged from 4.2% to 4.8%. The recoveries of As(III) and Se(IV) spiked at 25-100 ng l - 1 were in the range of 94.2-104.8%. After pre-concentration of a 5.0 ml sample, the sensitivity enhancement factors for As(III) and Se(IV) were 185 and 140, respectively. Accuracy was assessed by analysis of two standard reference materials (SRMs) and spiked recovery experiments. The method was successfully applied to the accurate and reliable determination of total As and total Se by HG-AAS after pre-reduction with a mixture of L-cysteine and tartaric acid. Finally, the method was shown to be rapid and sensitive, with good results for extraction, pre-concentration and determination of total As and Se contents (as As(III) and Se(IV)) from food samples.

Time course for measuring endolymphatic size in healthy volunteers following intravenous administration of gadoteridol.

PubMed

Naganawa, Shinji; Suzuki, Kojiro; Yamazaki, Masahiro; Sakurai, Yasuo; Ikeda, Mitsuru

2014-01-01

We developed semi-quantitative methods to measure endolymphatic size on images obtained 4 hours after intravenous administration of single-dose gadolinium-based contrast medium (IV-SD-GBCM) and found little variation in results between observers. We used the methods to measure the size of the endolymph in healthy volunteers at various times after IV-SD-GBCM and attempted to determine the optimal timing for the evaluation. In 8 healthy male volunteers, we obtained heavily T2-weighted 3-dimensional fluid-attenuated inversion recovery (hT2W-3D-FLAIR) images 1.5, 3, 4.5, and 6 hours after IV-SD-GBCM as positive perilymph images (PPI) as well as acquiring positive endolymph images (PEI) and magnetic resonance cisternography (MRC). To evaluate the endolymph, we generated 2 kinds of processed images (HYDROPS-Mi2 and HYDROPS2-Mi2) by subtracting PEI or MRC from PPI as previously proposed. We semi-quantitatively measured the ratio of the area of the endolymph (%EL) to that of total lymph on the 2 kinds of generated images for the cochlea and vestibule according to the previously proposed method. We analyzed statistics to evaluate the change in %EL over time and used analysis of variance (ANOVA) for a 2 × 4 repeated-measures design to assess difference in image type. We adopted 5% as a significance level. The %EL was significantly larger at 1.5 hours after IV-SD-GBCM than at 3, 4.5, and 6 hours in both the cochlea and vestibule for both kinds of generated images. Between 4.5 and 6 hours, the %EL plateaued for both the cochlea and vestibule, and the 2 kinds of generated images did not differ significantly. A delay of 1.5 hours after IV-SD-GBCM is not sufficient to evaluate endolymphatic size. The %EL plateaus between 4.5 and 6 hours. These data might be valuable for further clinical studies.

Extraction chromatographic method of preconcentration, estimation and concomitant separation of vanadium (IV) with silica gel-versatic 10 composite.

PubMed

Mandal, Bhabatosh; Barman, Milan K; Srivastava, Bhavya

2014-10-01

A selective method has been developed for the extraction chromatographic separation of V(IV) with SSG-V-10 composite. V(IV) was quantitatively extracted at pH 5.0-6.0, and its loading has been confirmed by EDAX. XRD studies indicate that the SSG network does not get influenced by impregnation with V-10 or by the sorption of V(IV) on the surface of SSG-V-10 composite. The binding between SSG and V-10 is a hydrophobic interaction only, and it takes place at the surface of the hydrophobic SSG. TGA-DTA analysis indicates its thermal stability up to 45°C. The exchange capacity (1.65 meq of H(+) g(-1)), break-through capacity (34.5 mg g(-1)) and column efficiency (360) of the extractor have been rationalized by Brunauer-Emmett-Teller analysis (SA = 149.46 m(2) g(-1) and PV = 0.2001 mL g(-1) at a relative pressure of 0.9-1.0). The sorption process was endothermic (ΔH = 12.63 kJ mol(-1)), entropy gaining (ΔS = 0.271 kJ mol(-1) K(-1)) and spontaneous (ΔG = -68.241 kJ mol(-1)) in nature. Preconcentration factor has been optimized at 182.3 ± 0.2. Formation constants (Kf) of the metal centers [Zn(II) (0.6 × 10(3)), Cd(II) (0.9 × 10(4)), Pb(II) (0.6 × 10(5)), Cu(II) (0.2 × 10(5)), Al(III) (6.2 × 10(5)), Ga(III) (4.2 × 10(5)), Hg(II) (2.2 × 10(6)), Bi(III) (6.2 × 10(6)), Tl(III) (8.9 × 10(6)), Zr(IV) (6.8 × 10(9)), Fe(III) (0.9 × 10(9)) and V(IV) (0.8 × 10(6))] have been determined. The desorption constants Kdesorption (1.9 × 10(-2)) and [Formula: see text] have been determined. Rf values and selectivity factors for diverse metal ions have been determined. V(IV) has been separated from the synthetic and real samples containing its congeners. A plausible mechanism for the extraction of V(IV) has been suggested. © The Author [2013]. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

[Basic requirements on post-marketing clinical re-evaluation of chinese medicine and phase IV clinical trials].

PubMed

Xie, Yanming; Wang, Yanping; Tian, Feng; Wang, Yongyan

2011-10-01

As information on safety and effectiveness is not comprehensive, gained from the researches for listing approval of Chinese medicine, it is very necessary to conduct post-marketing clinical re-evaluation of Chinese medicine. Effectiveness, safety and economic evaluation are three main aspects of post-marketing clinical re-evaluation. In this paper, the difference and relations between the post-marketing clinical re-evaluation and the phase IV clinical trials were discussed, and the basic requests and suggestions were proposed, according to the domestic and foreign relevant regulations and experts' suggestions, and discussed the requirements of the phase IV clinical trials on indications, design methods, inclusion and exclusion criteria, sample size, etc.

Circuit analysis method for thin-film solar cell modules

NASA Technical Reports Server (NTRS)

Burger, D. R.

1985-01-01

The design of a thin-film solar cell module is dependent on the probability of occurrence of pinhole shunt defects. Using known or assumed defect density data, dichotomous population statistics can be used to calculate the number of defects expected in a module. Probability theory is then used to assign the defective cells to individual strings in a selected series-parallel circuit design. Iterative numerical calculation is used to calcuate I-V curves using cell test values or assumed defective cell values as inputs. Good and shunted cell I-V curves are added to determine the module output power and I-V curve. Different levels of shunt resistance can be selected to model different defect levels.

Stochastic optimization for the detection of changes in maternal heart rate kinetics during pregnancy

NASA Astrophysics Data System (ADS)

Zakynthinaki, M. S.; Barakat, R. O.; Cordente Martínez, C. A.; Sampedro Molinuevo, J.

2011-03-01

The stochastic optimization method ALOPEX IV has been successfully applied to the problem of detecting possible changes in the maternal heart rate kinetics during pregnancy. For this reason, maternal heart rate data were recorded before, during and after gestation, during sessions of exercises of constant mild intensity; ALOPEX IV stochastic optimization was used to calculate the parameter values that optimally fit a dynamical systems model to the experimental data. The results not only demonstrate the effectiveness of ALOPEX IV stochastic optimization, but also have important implications in the area of exercise physiology, as they reveal important changes in the maternal cardiovascular dynamics, as a result of pregnancy.

Primary Intravenous Set Consumption Across 3 Branded Infusion Pumps

PubMed Central

Hedlund, Nancy; Sarangpur, Shishir; Kayler, Shannon; O'Brien, Kathy

2017-01-01

This retrospective study of 6426 hip replacement, coronary artery bypass graft, and colectomy surgeries across 23 US hospitals found that intravenous (IV) set designs that can be interchanged for use both in gravity-fed and automated pump delivery systems are replaced less frequently than IV sets designed for use primarily by one delivery method. Semistructured interviews with nurses highlighted the impact of set design on nursing workflow when moving between gravity-fed and pump-based administration. Use of interchangeable, single-design IV sets across gravity and automated infusions minimizes disruptions to closed systems, may reduce nurses being distracted from patients' clinical needs when replacing sets, and may yield supply cost savings. PMID:28682999

Advanced Computational Thermal Fluid Physics (CTFP) and Its Assessment for Light Water Reactors and Supercritical Reactors

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

D.M. McEligot; K. G. Condie; G. E. McCreery

2005-10-01

Background: The ultimate goal of the study is the improvement of predictive methods for safety analyses and design of Generation IV reactor systems such as supercritical water reactors (SCWR) for higher efficiency, improved performance and operation, design simplification, enhanced safety and reduced waste and cost. The objective of this Korean / US / laboratory / university collaboration of coupled fundamental computational and experimental studies is to develop the supporting knowledge needed for improved predictive techniques for use in the technology development of Generation IV reactor concepts and their passive safety systems. The present study emphasizes SCWR concepts in the Generationmore » IV program.« less

Mariner IV Mission to Mars. Part I

NASA Technical Reports Server (NTRS)

James, Jack N.

1965-01-01

This technical report is a series of individual papers documenting the Mariner-Mars project from its beginning in 1962 following the successful Mariner-Venus mission. Part I is pre-encounter data. It includes papers on the design, development, and testing of Mariner IV, as well as papers detailing methods of maintaining communication with and obtaining data from the spacecraft during flight, and expected results during encounter with Mars. Part 11, post-encounter data, to be published later, will consist of documentation of the events taking place during Mariner IV's encounter with Mars and thereafter. The Mariner-Mars mission, the culmination of an era of spacecraft development, has contributed much new technology to be used in future projects.

Application of histogram analysis for the evaluation of vascular permeability in glioma by the K2 parameter obtained with the dynamic susceptibility contrast method: Comparisons with Ktrans obtained with the dynamic contrast enhance method and cerebral blood volume.

PubMed

Taoka, Toshiaki; Kawai, Hisashi; Nakane, Toshiki; Hori, Saeka; Ochi, Tomoko; Miyasaka, Toshiteru; Sakamoto, Masahiko; Kichikawa, Kimihiko; Naganawa, Shinji

2016-09-01

The "K2" value is a factor that represents the vascular permeability of tumors and can be calculated from datasets obtained with the dynamic susceptibility contrast (DSC) method. The purpose of the current study was to correlate K2 with Ktrans, which is a well-established permeability parameter obtained with the dynamic contrast enhance (DCE) method, and determine the usefulness of K2 for glioma grading with histogram analysis. The subjects were 22 glioma patients (Grade II: 5, III: 6, IV: 11) who underwent DSC studies, including eight patients in which both DSC and DCE studies were performed on separate days within 10days. We performed histogram analysis of regions of interest of the tumors and acquired 20th percentile values for leakage-corrected cerebral blood volume (rCBV20%ile), K2 (K220%ile), and for patients who underwent a DCE study, Ktrans (Ktrans20%ile). We evaluated the correlation between K220%ile and Ktrans20%ile and the statistical difference between rCBV20%ile and K220%ile. We found a statistically significant correlation between K220%ile and Ktrans20%ile (r=0.717, p<0.05). rCBV20%ile showed a significant difference between Grades II and III and between Grades II and IV, whereas K220%ile showed a statistically significant (p<0.05) difference between Grades II and IV and between Grades III and IV. The K2 value calculated from the DSC dataset, which can be obtained with a short acquisition time, showed a correlation with Ktrans obtained with the DCE method and may be useful for glioma grading when analyzed with histogram analysis. Copyright © 2016 Elsevier Inc. All rights reserved.

Identification, synthesis and structural characterization of process related and degradation impurities of acrivastine and validation of HPLC method.

PubMed

Kumar, Ajay; Devineni, Subba Rao; Dubey, Shailender Kumar; Kumar, Pradeep; Srivastava, Vishal; Ambulgekar, Girish; Jain, Mohit; Gupta, Dharmendra Kumar; Singh, Gurmeet; Kumar, Rajesh; Hiriyanna, S G; Kumar, Pramod

2016-10-17

Four impurities (Imp-I-IV) were detected using gradient HPLC method in few laboratory batches of acrivastine in the level of 0.03-0.12% and three impurities (Imp-I-III) were found to be known and one (Imp-IV) was unknown. In forced degradation study, the drug is degraded into four degradation products under oxidation and photolytic conditions. Two impurities (Imp-III and -IV) were concurred with process related impurities whereas Imp-V and -VI were identified as new degradation impurities. Based on LC-ESI/MS n study, the chemical structures of new impurities were presumed as 1-[(2E)-3-(4-methylphenyl)-3-{6-[(1E)-3-oxobut-1-en-1-yl]pyridin-2-yl}prop-2-en-1-yl]pyrrolidin-1-ium-1-olate (Imp-IV), 1-{[3-(4-methylphenyl)-3-{6-[(1E)-3-oxobut-1-en-1-yl]pyridin-2-yl}oxiran-2-yl]methyl}pyrrolidin-1-ium-1-olate (Imp-V) and 2-[2-(4-methylphenyl)-3-[(1-oxidopyrrolidin-1-ium-1-yl)methyl]oxiran-2-yl]-6-[(1E)-3-oxobut-1-en-1-yl]pyridin-1-ium-1-olate (Imp-VI), and confirmed by their synthesis followed by spectroscopic analysis, IR, NMR ( 1 H, 13 C) and mass. An efficient and selective high-performance liquid chromatography method has been developed and resolved well the drug related substances on a Phenomenex Gemini C-18 (250×4.6mm, particle size 5μm) column. The mobile phase was composed of sodium dihydrogen phosphate (10mM) and methanol, temperature at 25°C, and a PDA detector set at 254nm used for detection. The method was validated with respect to specificity, linearity, precision, accuracy, and sensitivity and satisfactory results were achieved. Identification, synthesis, characterization of impurities and method validation were first reported in this paper. Copyright © 2016 Elsevier B.V. All rights reserved.

WE-G-BRE-06: New Potential for Enhancing External Beam Radiotherapy for Lung Cancer Using FDA-Approved Concentrations of Cisplatin Or Carboplatin Nanoparticles Administered Via Inhalation

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

Hao, Y; Altundal, Y; Sajo, E

Purpose: This study investigates, for the first time, the dose enhancement to lung tumors due to cisplatin nanoparticles (CNPs) and carboplatin nanoparticles (CBNPs) administered via inhalation route (IR) during external beam radiotherapy. Methods: Using Monte Carlo generated 6 MV energy fluence spectra, a previously employed analytic method was used to estimate dose enhancement to lung tumor due to radiation-induced photoelectrons from CNPs administered via IR in comparison to intravenous (IV) administration. Previous studies have indicated about 5% of FDA-approved cisplatin concentrations reach the lung tumor via IV. Meanwhile recent experimental studies indicate that 3.5–14.6 times higher concentrations of CNPs canmore » reach the lung tumors by IR compared to IV. Taking these into account, the dose enhancement factor (DEF) defined as the ratio of the dose with and without CNPs was calculated for field size of 10 cm × 10 cm (sweeping gap), for a range of tumor depths and tumor sizes. Similar calculations were done for CBNPs. Results: For IR with 3.5 times higher concentrations than IV, and 2 cm diameter tumor, clinically significant DEF values of 1.19–1.30 were obtained for CNPs at 3–10 cm depth, respectively, in comparison to 1.06–1.09 for IV. For CBNPs, DEF values of 1.26–1.41 were obtained in comparison to 1.07–1.12 for IV. For IR with 14.6 times higher concentrations, higher DEF values were obtained e.g. 1.81–2.27 for CNPs. DEF increased with increasing field size or decreasing tumor size. Conclusions: Our preliminary results indicate that major dose enhancement to lung tumors can be achieved using CNPs/CBNPs administered via IR, in contrast to IV administration during external beam radiotherapy. These findings highlight a potential new approach for radiation boosting to lung tumors using CNPs/CBNPs administered via IR. This would, especially, be applicable during concomitant chemoradiotherapy, potentially allowing for dose enhancement while minimizing normal tissue toxicities.« less

Amplified QCM biosensor for type IV collagenase based on collagenase-cleavage of gold nanoparticles functionalized peptide.

PubMed

Dong, Zong-Mu; Jin, Xin; Zhao, Guang-Chao

2018-05-30

The present study develops a rapid, simple and efficient method for the determination of type IV collagenase by using a specific peptide-modified quartz crystal microbalance (QCM). A small peptide (P1), contains a specific sequence (Pro-Gly) and a terminal cysteine, was synthetized and immobilized to the surface of QCM electrode via the reaction between Au and thiol of the cysteine. The peptide bond between proline and glycine can be specific hydrolyzed cleavage by type IV collagenase, which enabled the modified electrode with a high selectivity toward type IV collagenase. The cleaving process caused a frequency change of QCM to give a signal related to the concentration of type IV collagenase. The morphologies of the modified electrodes were characterized by scanning electron microscope (SEM) and the specific hydrolyzed cleavage process was monitored by QCM. When P1 was modified with gold nanoparticles (P1-Au NPs), the signal could be amplified to further enhance the sensitivity of the designed sensor due to the high-mass of the modified Au NPs. Compared the direct unamplified assay, the values obtained for the limit of detection for type IV collagenase was 0.96 ng mL -1 , yielding about 6.5 times of magnitude improvement in sensitivity. This signal enhanced peptide based QCM biosensor for type IV collagenase also showed good selectivity and sensitivity in complex matrix. Copyright © 2018 Elsevier B.V. All rights reserved.

Computational Investigation of Technetium(IV) Incorporation into Inverse Spinels: Magnetite (Fe 3 O 4 ) and Trevorite (NiFe 2 O 4 )

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

Smith, Frances N.; Um, Wooyong; Taylor, Christopher D.

2016-05-17

Iron oxides and oxyhydroxides play an important role in minimizing the mobility of redox-sensitive elements in engineered and natural environments. For the radionuclide technetium-99 (Tc), these phases hold promise as primary hosts for increasing Tc loading into glass waste form matrices, or as secondary sinks during the long-term storage of nuclear materials. Recent experiments show that the inverse spinel, magnetite [Fe(II)Fe(III)2O4], can incorporate Tc(IV) into its octahedral sub-lattice, and in that same class of materials, trevorite [Ni(II)Fe(III)2O4] is also being investigated for its ability to host Tc(IV). However, questions remain regarding the most energetically favorable charge-compensation mechanism for Tc(IV) incorporationmore » in each structure, which will affect Tc behavior under changing waste processing or storage conditions. Here, quantum-mechanical methods were used to evaluate incorporation energies and optimized lattice bonding environments for three different, charge-balanced Tc(IV) incorporation mechanisms in magnetite and trevorite. In both cases, the removal of two octahedral Fe(II) or Ni(II) ions upon the addition of Tc(IV) to an octahedral site is the most stable mechanism, relative to the creation of octahedral Fe(III) defects or increasing octahedral Fe(II) content. Following hydration-energy corrections, Tc(IV) incorporation into magnetite is energetically favorable while an energy barrier exists for trevorite.« less

Comparison of Effectiveness of Betamethasone gel Applied to the Tracheal Tube and IV Dexamethasone on Postoperative Sore Throat: A Randomized Controlled Trial

PubMed Central

Tabari, Masoomeh; Soltani, Ghasem; Zirak, Nahid; Alipour, Mohammad; Khazaeni, Kamran

2013-01-01

Introduction: Postoperative sore throat is a common complaint in patients with endotracheal intubation and has potentially dangerous complications. This randomized controlled trial study investigated the incidence of postoperative sore throat after general anesthesia when betamethasone gel is applied to a tracheal tube compared with when IV dexamethasone is prescribed. Materials and Methods: Two hundred and twenty five American Society of Anesthesiologist (ASA)-class I and II patients undergoing elective abdominal surgery with tracheal intubation were randomly divided into three groups: betamethasone gel, intravenous (IV) dexamethasone, and control groups. In the post-anesthesia care unit, a blinded anesthesiologist interviewed all patients regarding postoperative sore throat at 1,6, and 24 hours after surgery. Results: The incidence of sore throat was significantly lower in the betamethasone gel group compared with the IV dexamethasone and control groups, 1, 6, and 24 hours after surgery. In the first day after surgery 10.7% of the betamethasone group had sore throat whereas 26.7% of the IV dexamethasone group and 30.7% of the control group had sore throat. Bucking before extubation was observed in 14(18.4%), 8(10.4%), and 9(12.2%) patients, in the IV dexamethasone, betamethasone gel, and control group, respectively. Conclusion: We concluded that wide spread application of betamethasone gel over tracheal tubes effectively mitigates postoperative sore throat, compared with IV dexamethasone application. PMID:24303443

Asynchronous brain-computer interface for cognitive assessment in people with cerebral palsy

NASA Astrophysics Data System (ADS)

Alcaide-Aguirre, R. E.; Warschausky, S. A.; Brown, D.; Aref, A.; Huggins, J. E.

2017-12-01

Objective. Typically, clinical measures of cognition require motor or speech responses. Thus, a significant percentage of people with disabilities are not able to complete standardized assessments. This situation could be resolved by employing a more accessible test administration method, such as a brain-computer interface (BCI). A BCI can circumvent motor and speech requirements by translating brain activity to identify a subject’s response. By eliminating the need for motor or speech input, one could use a BCI to assess an individual who previously did not have access to clinical tests. Approach. We developed an asynchronous, event-related potential BCI-facilitated administration procedure for the peabody picture vocabulary test (PPVT-IV). We then tested our system in typically developing individuals (N  =  11), as well as people with cerebral palsy (N  =  19) to compare results to the standardized PPVT-IV format and administration. Main results. Standard scores on the BCI-facilitated PPVT-IV, and the standard PPVT-IV were highly correlated (r  =  0.95, p  <  0.001), with a mean difference of 2.0  ±  6.4 points, which is within the standard error of the PPVT-IV. Significance. Thus, our BCI-facilitated PPVT-IV provided comparable results to the standard PPVT-IV, suggesting that populations for whom standardized cognitive tests are not accessible could benefit from our BCI-facilitated approach.

[A novel method of multi-channel feature extraction combining multivariate autoregression and multiple-linear principal component analysis].

PubMed

Wang, Jinjia; Zhang, Yanna

2015-02-01

Brain-computer interface (BCI) systems identify brain signals through extracting features from them. In view of the limitations of the autoregressive model feature extraction method and the traditional principal component analysis to deal with the multichannel signals, this paper presents a multichannel feature extraction method that multivariate autoregressive (MVAR) model combined with the multiple-linear principal component analysis (MPCA), and used for magnetoencephalography (MEG) signals and electroencephalograph (EEG) signals recognition. Firstly, we calculated the MVAR model coefficient matrix of the MEG/EEG signals using this method, and then reduced the dimensions to a lower one, using MPCA. Finally, we recognized brain signals by Bayes Classifier. The key innovation we introduced in our investigation showed that we extended the traditional single-channel feature extraction method to the case of multi-channel one. We then carried out the experiments using the data groups of IV-III and IV - I. The experimental results proved that the method proposed in this paper was feasible.

Prevalence of and Risk Factors for Asymptomatic Inflammatory (NIH-IV) Prostatitis in Chinese Men

PubMed Central

Wu, Chunlei; Zhang, Zhifu; Lu, Zheng; Liao, Ming; Zhang, Youjie; Xie, Yuanliang; Guo, Xuefeng; Yu, Xiaoxiang; Yang, Xiaobo; Gao, Yong; Tan, Aihua; Mo, Zengnan

2013-01-01

Background While many investigators have studied symptomatic prostatitis, little research has been done with regard to asymptomatic (NIH-IV) prostatitis. Purpose To describe the prevalence of and risk factors for NIH-IV prostatitis among a large male population. Methods The study population was comprised of 1,868 men at the second phase recruitment of a population-based cohort in China. Asymptomatic and symptomatic men were defined by the National Institutes of Health Chronic Prostatitis (CP) Symptom Index. Meanwhile, EPS specimens and their leukocyte count were collected. Lifestyle and demographic characteristics were obtained through a questionnaire. Results Prevalence of NIH-IV prostatitis was 21.1% among 1,868 asymptomatic men aged 19–78 years and increased with age. After adjusteing for potential confounding variables (age, smoking habits, alcohol drinking habits, education, physical activity, hypertension, dyslipidemia, obesity and diabetes), age remained a significant factor for NIH-IV prostatitis (OR = 1.35; 95% CI = 1.06–1.71; P = 0.01) and the risk of NIH-IV prostatitis was significantly higher in smokers≧15 pack/years than non-smokers (OR = 1.33; 95% CI = 1.01–1.75; P = 0.03). In addition, compared with non-drinkers, the OR of NIH-IV prostatitis in drinkers ≧1 drinks/week was 1.35 (95% CI = 1.03, 1.77, p = 0.02) after adjusting for the other variables above. In addition, having less than a college education may be a risk factor for NIH-IV prostatitis, although a statistically significant difference did not exist in our data (OR = 1.22; 95% CI = 0.97–1.52; P = 0.08). Conclusions Our findings suggest that NIH-IV prostatitis is prevalent in China. Age, smoking, drinking and lower education levels were associated with an increased risk of NIH-IV prostatitis. The prevalence of NIH-IV prostatitis should be taken into account when estimating the total prevalence of CP in future studies. PMID:23967188

Non-equilibrium ionization by a periodic electron beam. II. Synthetic Si IV and O IV transition region spectra

NASA Astrophysics Data System (ADS)

Dzifčáková, Elena; Dudík, Jaroslav

2018-03-01

Context. Transition region (TR) spectra typically show the Si IV 1402.8 Å line to be enhanced by a factor of 5 or more compared to the neighboring O IV 1401.2 Å, contrary to predictions of ionization equilibrium models and the Maxwellian distribution of particle energies. Non-equilibrium effects in TR spectra are therefore expected. Aims: To investigate the combination of non-equilibrium ionization and high-energy particles, we apply the model of the periodic electron beam, represented by a κ-distribution that recurs at periods of several seconds, to plasma at chromospheric temperatures of 104 K. This simple model can approximate a burst of energy release involving accelerated particles. Methods: Instantaneous time-dependent charge states of silicon and oxygen were calculated and used to synthesize the instantaneous and period-averaged spectra of Si IV and O IV. Results: The electron beam drives the plasma out of equilibrium. At electron densities of Ne = 1010 cm-3, the plasma is out of ionization equilibrium at all times in all cases we considered, while for a higher density of Ne = 1011 cm-3, ionization equilibrium can be reached toward the end of each period, depending on the conditions. In turn, the character of the period-averaged synthetic spectra also depends on the properties of the beam. While the case of κ = 2 results in spectra with strong or even dominant O IV, higher values of κ can approximate a range of observed TR spectra. Spectra similar to typically observed spectra, with the Si IV 1402.8 Å line about a factor 5 higher than O IV 1401.2 Å, are obtained for κ = 3. An even higher value of κ = 5 results in spectra that are exclusively dominated by Si IV, with negligible O IV emission. This is a possible interpretation of the TR spectra of UV (Ellerman) bursts, although an interpretation that requires a density that is 1-3 orders of magnitude lower than for equilibrium estimates. Movies associated to Fig. A.1 are available at http://https://www.aanda.org

Study of uranium oxidation states in geological material.

PubMed

Pidchenko, I; Salminen-Paatero, S; Rothe, J; Suksi, J

2013-10-01

A wet chemical method to determine uranium (U) oxidation states in geological material has been developed and tested. The problem faced in oxidation state determinations with wet chemical methods is that U redox state may change when extracted from the sample material, thereby leading to erroneous results. In order to quantify and monitor U redox behavior during the acidic extraction in the procedure, an analysis of added isotopic redox tracers, (236)U(VI) and (232)U(IV), and of variations in natural uranium isotope ratio ((234)U/(238)U) of indigenous U(IV) and U(VI) fractions was performed. Two sample materials with varying redox activity, U bearing rock and U-rich clayey lignite sediment, were used for the tests. The Fe(II)/Fe(III) redox-pair of the mineral phases was postulated as a potentially disturbing redox agent. The impact of Fe(III) on U was studied by reducing Fe(III) with ascorbic acid, which was added to the extraction solution. We observed that ascorbic acid protected most of the U from oxidation. The measured (234)U/(238)U ratio in U(IV) and U(VI) fractions in the sediment samples provided a unique tool to quantify U oxidation caused by Fe(III). Annealing (sample heating) to temperatures above 500 °C was supposed to heal ionizing radiation induced defects in the material that can disturb U redox state during extraction. Good agreement between two independent methods was obtained for DL-1a material: an average 38% of U(IV) determined by redox tracer corrected wet chemistry and 45% for XANES. Copyright © 2013 Elsevier Ltd. All rights reserved.

Mendelian randomization with Egger pleiotropy correction and weakly informative Bayesian priors.

PubMed

Schmidt, A F; Dudbridge, F

2017-12-15

The MR-Egger (MRE) estimator has been proposed to correct for directional pleiotropic effects of genetic instruments in an instrumental variable (IV) analysis. The power of this method is considerably lower than that of conventional estimators, limiting its applicability. Here we propose a novel Bayesian implementation of the MR-Egger estimator (BMRE) and explore the utility of applying weakly informative priors on the intercept term (the pleiotropy estimate) to increase power of the IV (slope) estimate. This was a simulation study to compare the performance of different IV estimators. Scenarios differed in the presence of a causal effect, the presence of pleiotropy, the proportion of pleiotropic instruments and degree of 'Instrument Strength Independent of Direct Effect' (InSIDE) assumption violation. Based on empirical plasma urate data, we present an approach to elucidate a prior distribution for the amount of pleiotropy. A weakly informative prior on the intercept term increased power of the slope estimate while maintaining type 1 error rates close to the nominal value of 0.05. Under the InSIDE assumption, performance was unaffected by the presence or absence of pleiotropy. Violation of the InSIDE assumption biased all estimators, affecting the BMRE more than the MRE method. Depending on the prior distribution, the BMRE estimator has more power at the cost of an increased susceptibility to InSIDE assumption violations. As such the BMRE method is a compromise between the MRE and conventional IV estimators, and may be an especially useful approach to account for observed pleiotropy. © The Author 2017. Published by Oxford University Press on behalf of the International Epidemiological Association.

Norelgestromin/ethinyl estradiol intravenous infusion formulation optimization, stability and compatibility testing: A case study to overcome polysorbate 80 interference in chromatographic analysis.

PubMed

Abdallah, Inas A; Hammell, Dana C; Hassan, Hazem E; Stinchcomb, Audra L

2016-06-05

Norelgestromin/ethinyl estradiol is a progestin/estrogen combination hormonal contraceptive indicated for the prevention of pregnancy in women. The very poor solubility and wettability of these drugs, along with their high potency (adsorption issues), give rise to difficulties in designing intravenous (IV) formulations to assess absolute bioavailability of products containing both drugs. The purpose of this study was to develop an IV formulation, evaluate its stability under different conditions and evaluate its compatibility with IV sets for potential use in absolute bioavailability studies in humans. Also, a selective high-performance liquid chromatography (HPLC) method for quantification of ethinyl estradiol and norelgestromin in polysorbate 80 matrix was developed and validated. Norelgestromin/ethinyl estradiol IV solution was prepared using sterile water for injection with 2.5% ethanol and 2.5% polysorbate 80 as a cosolvent/surfactant system to obtain a final drug solution of 25μg ethinyl estradiol and 252μg norelgestromin from a concentrated stock drug solution. The stabilities of the concentrated stock and IV solutions were assessed after storing them in the refrigerator (3.7±0.6°C) and at room temperature (19.5±0.5°C), respectively. Additional studies were conducted to examine the stability of the IV solution using an Alarias(®) low sorbing IV administration set with and without an inline filter. The solution was allowed to drip at 1mL/min over a 60min period. Samples were obtained at the beginning, middle and end of the 60min duration. The chemical stability was evaluated for up to 10 days. Norelgestromin and ethinyl estradiol concentration, purity, and degradant levels were determined using the HPLC method. The norelgestromin/ethinyl estradiol IV formulation met the chemical stability criteria when tested on day 1 through day 9 (216h). Norelgestromin concentrations assayed in stock and IV solutions were in the range of 90.0-98.5% and 90.9-98.8% after 9 days, respectively. As for ethinyl estradiol, the assayed concentrations were in the range of 91.8-100.9% and 92.7-100.8% for the stock and IV solutions, respectively. The administration set was found to be compatible with both drugs; the assayed concentrations were in the range of 99.2-100.3% for norelgestromin and 96.3-102.7% for ethinyl estradiol, but the inline filter showed some adsorption of ethinyl estradiol; where the assayed concentrations were in the range of 98.1-99.8% for norelgestromin and 95.9-97.4% for ethinyl estradiol. The present study provided evidence supporting the suitability of an intravenous formulation for norelgestromin/ethinyl estradiol using ethanol/polysorbate 80 as a cosolvent/surfactant system. Both IV and concentrated stock solutions when stored at room temperature and refrigeration, respectively, were found to be chemically stable up to 9 days. These results indicated that this formulation is chemically stable and can be used over the time period tested. This IV formulation can be used to evaluate the absolute bioavailability of products containing norelgestromin and ethinyl estradiol provided that microbial testing of the IV formulation is performed. Copyright © 2016. Published by Elsevier B.V.

Nonstatic radiating spheres in general relativity

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

Krori, K.D.; Borgohain, P.; Sarma, R.

1985-02-15

The method of Herrera, Jimenez, and Ruggeri of obtaining nonstatic solutions of Einstein's field equations to study the evolution of stellar bodies is applied to obtain two models of nonstatic radiating spheres from two well-known static solutions of field equations, viz., Tolman's solutions IV and V. Whereas Tolman's type-IV model is found to be contracting for the period under investigation, Tolman's type-V model shows a bounce after attaining a minimum radius.

[DRG-based cost analysis of inpatient conservative treatment of stage III/IV peripheral arterial occlusive disease].

PubMed

Heidrich, H; Rogatti, W; Altmann, E; Bauersachs, R; Diehm, C; Fahrig, C; Lawall, H; Ranft, J; Schenker, M; Schweizer, H J; Stiegler, H; Wilke, M

2003-11-01

DRG-based cost analysis of inpatient conservative treatment of PAD stage III/IV BACKGROUND: In a prospective study carried out by the German Society of Angiology and the DRG Competence Center, Munich, the question was investigated whether the costs of conservative treatment of patients with PAOD stage III/IV (DRG F65) are adequately represented within the current G-DRG system. METHODS UND PATIENTS: Between September 1 and December 16, 2002, a total of 704 patients with DRG F65 (peripheral vascular diseases) were evaluated at 8 angiologic centers in Germany. Apart from the length of hospital stay, the total costs (cost equivalents) were calculated using a method developed by the DRG Research Group at the University of Münster. Moreover, the study population was compared with a German calculation sample for the DRGs F65A/B, as published by InEK. As it turned out, conservatively treated patients with PAOD stage III or IV (DRGs F65A/B) cause significantly (p < 0.001) higher costs and have significantly (p < 0.001) greater lengths of hospital stay than patients who were also assigned to DRG F65 because of other vascular diseases. At the same time it became clear that angiologic centers treat twice as many patients with critical limb ischemia in comparison with the German average. The reimbursement hitherto estimated by InEK covers not even half the cost actually produced by conservative treatment of PAD stage III/IV. To ensure a performance-related reimbursement, a new basis DRG for patients with PAD stage III/IV has to be created, as has ben proposed by the German Society of Angiology. Otherwise, adequate conservative therapy in accordance with existing guidelines, of patients who cannot be treated surgically or interventionally will not be possible any more in the future.

Speciation and determination of ultra trace amounts of inorganic tellurium in environmental water samples by dispersive liquid-liquid microextraction and electrothermal atomic absorption spectrometry.

PubMed

Najafi, Nahid Mashkouri; Tavakoli, Hamed; Alizadeh, Reza; Seidi, Shahram

2010-06-18

A simple and powerful method has been developed for the rapid and selective determination of Te(IV) and Te(VI), employing dispersive liquid-liquid microextraction combined with electrothermal atomic absorption spectrometry using palladium as permanent modifier. Under acidic conditions pH 1, only Te(IV) can form a complex with ammonium pyrrolidine dithiocarbamate (APDC) and therefore be extracted into fine droplets of carbon tetrachloride (extraction solvent) which are dispersed with ethanol into the water sample solution. After centrifugation, Te(IV) was determined in the sedimented organic phase while Te(VI) remained in the aqueous phase. Total inorganic tellurium was determined after the reduction of the Te(VI) to Te(IV). Te(VI) was calculated as the difference between the measured total inorganic tellurium and Te(IV) content. The effective parameters for improving the efficiency of microextraction process were investigated by using experimental and central composite designs. Under optimal conditions the enrichment factor was 125 and the calibration graph was linear in the range of 0.015-1 ng mL(-1) with detection limit and characteristic mass of 0.004 ng mL(-1) and 0.033 pg, respectively. The relative standard deviation for 0.5 ng mL(-1) of tellurium measurement was 3.6% (n=6) at ash and atomization temperature, 900 and 2600 degrees C, respectively. The recoveries of spiked Te(IV) and Te(VI) to the environmental water samples were 89.6-101.3% and 96.6-99.1%, respectively. The accuracy is also evaluated by applying the proposed method to certified reference material (NIST SRM 1643e), for which the result was in a good agreement with the certified values reported for this CRM (95% confidence level). 2010 Elsevier B.V. All rights reserved.

Development of a simple and fast voltammetric procedure for determination of trace quantity of Se(IV) in natural lake and river water samples.

PubMed

Grabarczyk, Malgorzata; Korolczuk, Mieczyslaw

2010-03-15

A simple and fast cathodic stripping voltammetric procedure for determination of trace quantity of Se(IV) in natural samples containing high concentrations of surfactants and humic substances was developed. The procedure exploiting selenium accumulation (from sample solution spiked with 0.1 mol L(-1) HClO(4) and 4 x 10(-4)mol L(-1) Cu(NO(3))(2)) as Cu(2)Se was employed as the initial method. The deposited Cu(2)Se was stripped by differential pulse cathodic potential scan. The interference from dissolved organic matter such as surfactants and humic substances was eliminated by adding Amberlite XAD-7 resin to the voltammetric cell. The whole procedure was applied to a single cell, which allows one to monitor the voltammetric scan. Optimum conditions for removing the surfactants and humic substances due to their adsorption on XAD-7 resin were evaluated. The method was tested on synthetic samples spiked with surfactants and humic substances. The calibration graph for Se(IV) under optimized conditions following the accumulation of 30s was linear in the range from 2 x 10(-9) to 2 x 10(-7)mol L(-1) and was found to obey the equation y=0.74x-0.61, where y and x are the peak current (nA) and Se(IV) concentration (nmol L(-1)), respectively. The linear correlation coefficient was r=0.9993. The relative standard deviation for determination of Se(IV) at the concentration of 1 x 10(-8)mol L(-1) was 3.7% (n=5). The detection limit estimated from three times the standard deviation for low Se(IV) concentration and accumulation time of 30s was about 7.8 x 10(-10)mol L(-1). The presented procedure was successfully applied to selenium determination in TMRAIN-95 certified reference material and to real samples including spiked lake and river waters for selenium speciation. (c) 2009 Elsevier B.V. All rights reserved.

Intravenous nicorandil versus adenosine for fractional flow reserve measurement: a crossover, randomized study.

PubMed

Nishi, Takeshi; Kitahara, Hideki; Fujimoto, Yoshihide; Nakayama, Takashi; Nagashima, Kengo; Hanaoka, Hideki; Kobayashi, Yoshio

2018-06-01

Nicorandil has vasodilatory effects on both the epicardial coronary arteries and the coronary microvasculature, thereby increasing coronary blood flow. The objective of the present study was to investigate the effectiveness of intravenous (IV) nicorandil infusion for fractional flow reserve (FFR) measurement. In this crossover randomized study, 49 patients underwent FFR measurement with a consecutive randomized order of patient-blind infusions of continuous IV adenosine administration and a single bolus IV administration of nicorandil. The primary endpoint was the difference between the FFR by nicorandil and the FFR by adenosine, as assessed by the Bland-Altman method. The mean FFR value measured by nicorandil was not significantly different from that measured by adenosine [0.8125 ± 0.1349 vs. 0.7978 ± 0.124; mean difference, 0.0147 (95% confidence interval - 0.0373, 0.0667); P = 0.58]. There was no clinically significant diagnostic discordance, with the FFR by nicorandil > 0.80 and that by adenosine < 0.75. Hyperemia was achieved earlier using nicorandil than adenosine (34 ± 13 vs. 58 ± 15, P < 0.001). The duration of hyperemia after IV nicorandil was variable (6-570 s, mean 89 ± 98 s). IV nicorandil decreased systolic blood pressure by 32 ± 16 mm Hg (24 ± 10%) from baseline. Linear regression analysis showed that the average FFR value and the difference in systolic blood pressure were significantly associated with the bias in the FFR value between the two drugs. In conclusions, the results of the present study suggest that IV nicorandil can achieve maximal hyperemia easily and rapidly, providing an acceptable diagnostic performance for FFR assessment. However, a wide range of variation in hyperemic plateau and a decrease in blood pressure are the major limitations of this method.

Reconstructing Rodinia by Fitting Neoproterozoic Continental Margins

USGS Publications Warehouse

Stewart, John H.

2009-01-01

Reconstructions of Phanerozoic tectonic plates can be closely constrained by lithologic correlations across conjugate margins by paleontologic information, by correlation of orogenic belts, by paleomagnetic location of continents, and by ocean floor magmatic stripes. In contrast, Proterozoic reconstructions are hindered by the lack of some of these tools or the lack of their precision. To overcome some of these difficulties, this report focuses on a different method of reconstruction, namely the use of the shape of continents to assemble the supercontinent of Rodinia, much like a jigsaw puzzle. Compared to the vast amount of information available for Phanerozoic systems, such a limited approach for Proterozoic rocks, may seem suspect. However, using the assembly of the southern continents (South America, Africa, India, Arabia, Antarctica, and Australia) as an example, a very tight fit of the continents is apparent and illustrates the power of the jigsaw puzzle method. This report focuses on Neoproterozoic rocks, which are shown on two new detailed geologic maps that constitute the backbone of the study. The report also describes the Neoproterozoic, but younger or older rocks are not discussed or not discussed in detail. The Neoproterozoic continents and continental margins are identified based on the distribution of continental-margin sedimentary and magmatic rocks that define the break-up margins of Rodinia. These Neoproterozoic continental exposures, as well as critical Neo- and Meso-Neoproterozoic tectonic features shown on the two new map compilations, are used to reconstruct the Mesoproterozoic supercontinent of Rodinia. This approach differs from the common approach of using fold belts to define structural features deemed important in the Rodinian reconstruction. Fold belts are difficult to date, and many are significantly younger than the time frame considered here (1,200 to 850 Ma). Identifying Neoproterozoic continental margins, which are primarily extensional in origin, supports recognition of the Neoproterozoic fragmentation pattern of Rodinia and outlines the major continental masses that, prior to the breakup, formed the supercontinent. Using this pattern, Rodinia can be assembled by fitting the pieces together. Evidence for Neoproterozoic margins is fragmentary. The most apparent margins are marked by miogeoclinal deposits (passive-margin deposits). The margins can also be outlined by the distribution of continental-margin magmatic-arc rocks, by juvenile ocean-floor rocks, or by the presence of continent-ward extending aulacogens. Most of the continental margins described here are Neoproterozoic, and some had an older history suggesting that they were major, long-lived lithospheric flaws. In particular, the western margin of North America appears to have existed for at least 1,470 Ma and to have been reactivated many times in the Neoproterozoic and Phanerozoic. The inheritance of trends from the Mesoproterozoic by the Neoproterozoic is particularly evident along the eastern United States, where a similarity of Mesoproterozoic (Grenville) and Neoproterozoic trends, as well as Paleozoic or Mesozoic trends, is evident. The model of Rodinia presented here is based on both geologic and paleomagnetic information. Geologic evidence is based on the distribution and shape of Neoproterozoic continents and on assembling these continents so as to match the shape, history, and scale of adjoining margins. The proposed model places the Laurasian continents?Baltica, Greenland, and Laurentia?west of the South American continents (Amazonia, Rio de La Plata, and Sa? Francisco). This assembly is indicated by conjugate pairs of Grenville-age rocks on the east side of Laurentia and on the west side of South America. In the model, predominantly late Neoproterozoic magmatic-arc rocks follow the trend of the Grenville rocks. The boundary between South America and Africa is interpreted as the site of a Wilson cycle

Determination of dipyrone in pharmaceutical preparations based on the chemiluminescent reaction of the quinolinic hydrazide-H2O2-vanadium(IV) system and flow-injection analysis.

PubMed

Pradana Pérez, Juan A; Durand Alegría, Jesús S; Hernando, Pilar Fernández; Sierra, Adolfo Narros

2012-01-01

A rapid, economic and sensitive chemiluminescent method involving flow-injection analysis was developed for the determination of dipyrone in pharmaceutical preparations. The method is based on the chemiluminescent reaction between quinolinic hydrazide and hydrogen peroxide in a strongly alkaline medium, in which vanadium(IV) acts as a catalyst. Principal chemical and physical variables involved in the flow-injection system were optimized using a modified simplex method. The variations in the quantum yield observed when dipyrone was present in the reaction medium were used to determine the concentration of this compound. The proposed method requires no preconcentration steps and reliably quantifies dipyrone over the linear range 1-50 µg/mL. In addition, a sample throughput of 85 samples/h is possible. Copyright © 2011 John Wiley & Sons, Ltd.

Approximating a DSM-5 Diagnosis of PTSD Using DSM-IV Criteria

PubMed Central

Rosellini, Anthony J.; Stein, Murray B.; Colpe, Lisa J.; Heeringa, Steven G.; Petukhova, Maria V.; Sampson, Nancy A.; Schoenbaum, Michael; Ursano, Robert J.; Kessler, Ronald C.

2015-01-01

Background Diagnostic criteria for DSM-5 posttraumatic stress disorder (PTSD) are in many ways similar to DSM-IV criteria, raising the possibility that it might be possible to closely approximate DSM-5 diagnoses using DSM-IV symptoms. If so, the resulting transformation rules could be used to pool research data based on the two criteria sets. Methods The Pre-Post Deployment Study (PPDS) of the Army Study to Assess Risk and Resilience in Servicemembers (Army STARRS) administered a blended 30-day DSM-IV and DSM-5 PTSD symptom assessment based on the civilian PTSD Checklist for DSM-IV (PCL-C) and the PTSD Checklist for DSM-5 (PCL-5). This assessment was completed by 9,193 soldiers from three US Army Brigade Combat Teams approximately three months after returning from Afghanistan. PCL-C items were used to operationalize conservative and broad approximations of DSM-5 PTSD diagnoses. The operating characteristics of these approximations were examined compared to diagnoses based on actual DSM-5 criteria. Results The estimated 30-day prevalence of DSM-5 PTSD based on conservative (4.3%) and broad (4.7%) approximations of DSM-5 criteria using DSM-IV symptom assessments were similar to estimates based on actual DSM-5 criteria (4.6%). Both approximations had excellent sensitivity (92.6-95.5%), specificity (99.6-99.9%), total classification accuracy (99.4-99.6%), and area under the receiver operating characteristic curve (0.96-0.98). Conclusions DSM-IV symptoms can be used to approximate DSM-5 diagnoses of PTSD among recently-deployed soldiers, making it possible to recode symptom-level data from earlier DSM-IV studies to draw inferences about DSM-5 PTSD. However, replication is needed in broader trauma-exposed samples to evaluate the external validity of this finding. PMID:25845710

Mortality Prediction Using Acute Physiology and Chronic Health Evaluation II and Acute Physiology and Chronic Health Evaluation IV Scoring Systems: Is There a Difference?

PubMed Central

Venkataraman, Ramesh; Gopichandran, Vijayaprasad; Ranganathan, Lakshmi; Rajagopal, Senthilkumar; Abraham, Babu K; Ramakrishnan, Nagarajan

2018-01-01

Background: Mortality prediction in the Intensive Care Unit (ICU) setting is complex, and there are several scoring systems utilized for this process. The Acute Physiology and Chronic Health Evaluation (APACHE) II has been the most widely used scoring system; although, the more recent APACHE IV is considered an updated and advanced prediction model. However, these two systems may not give similar mortality predictions. Objectives: The aim of this study is to compare the mortality prediction ability of APACHE II and APACHE IV scoring systems among patients admitted to a tertiary care ICU. Methods: In this prospective longitudinal observational study, APACHE II and APACHE IV scores of ICU patients were computed using an online calculator. The outcome of the ICU admissions for all the patients was collected as discharged or deceased. The data were analyzed to compare the discrimination and calibration of the mortality prediction ability of the two scores. Results: Out of the 1670 patients' data analyzed, the area under the receiver operating characteristic of APACHE II score was 0.906 (95% confidence interval [CI] – 0.890–0.992), and APACHE IV score was 0.881 (95% CI – 0.862–0.890). The mean predicted mortality rate of the study population as given by the APACHE II scoring system was 44.8 ± 26.7 and as given by APACHE IV scoring system was 29.1 ± 28.5. The observed mortality rate was 22.4%. Conclusions: The APACHE II and IV scoring systems have comparable discrimination ability, but the calibration of APACHE IV seems to be better than that of APACHE II. There is a need to recalibrate the scales with weights derived from the Indian population. PMID:29910542

Influence of experimental history on nicotine self-administration in squirrel monkeys.

PubMed

Desai, Rajeev I; Sullivan, Katherine A; Kohut, Stephen J; Bergman, Jack

2016-06-01

Methods for establishing robust long-term self-administration of intravenous (i.v.) nicotine, the primary psychoactive agent in tobacco, are not well-established in laboratory animals. Here, we examine the use of a fading procedure to establish robust and consistent i.v. nicotine self-administration under second-order schedule conditions in squirrel monkeys. First, self-administration behavior was developed in two groups of male squirrel monkeys using a second-order fixed-interval 5-min schedule with fixed-ratio 5 units (FI 5-min (FR5: S)). Comparable performances were maintained by i.v. cocaine (0.032 mg/kg/injection (inj); group A, n = 3) and the combination of food delivery (20-30 % condensed milk) and 0.01 mg/kg/inj i.v. nicotine (group B, n = 3). Subsequently, the concentration of condensed milk was gradually reduced to zero in the second group and self-administration behavior was maintained by i.v. nicotine alone. Next, self-administration of a range of doses of i.v. nicotine (0.001-0.032 mg/kg/inj) and, in additional experiments, the minor tobacco alkaloid anatabine (0.01-0.18 mg/kg/inj) was studied in both groups. Results show that nicotine and anatabine had reinforcing effects in both groups. However, optimal doses of nicotine and anatabine maintained significantly higher rates of i.v. self-administration behavior in subjects trained with the fading procedure than in subjects provided with a history of cocaine-maintained responding. These results illustrate conditions under which robust i.v. nicotine self-administration can be established in squirrel monkeys and the influence of prior experimental history in the expression of reinforcing effects of nicotine and anatabine.

Crosswalk between DSM-IV Dependence and DSM-5 Substance Use Disorders for Opioids, Cannabis, Cocaine and Alcohol

PubMed Central

Compton, Wilson M.; Dawson, Deborah A.; Goldstein, Risë B.; Grant, Bridget F.

2013-01-01

Background Ascertaining agreement between DSM-IV and DSM-5 is important to determine the applicability of treatments for DSM-IV conditions to persons diagnosed according to the proposed DSM-5. Methods Data from a nationally representative sample of US adults were used to compare concordance of past-year DSM-IV Opioid, Cannabis, Cocaine and Alcohol Dependence with past-year DSM-5 disorders at thresholds of 3+, 4+ 5+ and 6+ positive DSM-5 criteria among past-year users of opioids (n=264), cannabis (n=1,622), cocaine (n=271) and alcohol (n=23,013). Substance-specific 2×2 tables yielded overall concordance (kappa), sensitivity, specificity, positive predictive values (PPV) and negative predictive values (NPV). Results For DSM-IV Alcohol, Cocaine and Opioid Dependence, optimal concordance occurred when 4+ DSM-5 criteria were endorsed, corresponding to the threshold for moderate DSM-5 Alcohol, Cocaine and Opioid Use Disorders. Maximal concordance of DSM-IV Cannabis Dependence and DSM-5 Cannabis Use Disorder occurred when 6+ criteria were endorsed, corresponding to the threshold for severe DSM-5 Cannabis Use Disorder. At these optimal thresholds, sensitivity, specificity, PPV and NPV generally exceeded 85% (>75% for cannabis). Conclusions Overall, excellent correspondence of DSM-IV Dependence with DSM-5 Substance Use Disorders was documented in this general population sample of alcohol, cannabis, cocaine and opioid users. Applicability of treatments tested for DSM-IV Dependence is supported by these results for those with a DSM-5 Alcohol, Cocaine or Opioid Use Disorder of at least moderate severity or Severe Cannabis Use Disorder. Further research is needed to provide evidence for applicability of treatments for persons with milder substance use disorders. PMID:23642316