DOT National Transportation Integrated Search
1996-02-01
This report describes the initial formative evaluation of the Federal Aviation Administration (FAA) College Training Initiative - Air Traffic Control Specialist (CTI-ATCS) Program. The purpose of the CTI-ATCS program is to test "the concept that non-...
Formative Evaluation of the Understanding the Early Years Initiative. Final Report
ERIC Educational Resources Information Center
Human Resources and Skills Development Canada, 2009
2009-01-01
This report presents the findings of the formative evaluation of the Understanding the Early Years (UEY) Initiative. The evaluation was conducted to examine issues of implementation and design, early progress in achieving immediate objectives, and issues related to accountability. The evaluation team was also asked to provide preliminary guidance…
Formative Evaluation of the Targeted Initiative for Older Workers. Final Report
ERIC Educational Resources Information Center
Human Resources and Skills Development Canada, 2010
2010-01-01
This report presents the findings and conclusions, and recommendations for the Formative Evaluation of the Targeted Initiative for Older Workers (TIOW). The TIOW was introduced in 2006 to help older workers in vulnerable communities who had lost their jobs to extend their labour market participation and reintegrate into employment. The TIOW is…
NASA Technical Reports Server (NTRS)
Morello, S. A.; Knox, C. E.; Steinmetz, G. G.
1977-01-01
The results of a flight evaluation of two electronic display formats for the approach to landing under instrument conditions are presented. The evaluation was conducted for a base-line electronic display format and for the same format with runway symbology and track information added. The evaluation was conducted during 3 deg, manual straight-in approaches with and without initial localizer offsets. Flight path tracking performance data and pilot subjective comments were examined with regard to the pilot's ability to capture and maintain localizer and glide slope by using both display formats.
Evaluation of the Michigan Public School Academy Initiative: Final Report [and] Executive Summary.
ERIC Educational Resources Information Center
Horn, Jerry; Miron, Gary
This is the final report of a one-year evaluation of the Michigan Public School Academy (PSA) initiative. The evaluation involved both formative and summative evaluations and used both qualitative and quantitative methods. The study was conducted between October 1997 and December 1998. Data-collection methods included a charter-school survey and a…
ERIC Educational Resources Information Center
Crossouard, Barbara
2009-01-01
Drawing upon data arising from an evaluation carried out for the Jersey educational authority, this article discusses the interaction of two professional development initiatives, formative assessment and critical skills thinking, bringing the two initiatives together from the perspective of Cultural Historical Activity Theory (CHAT). This allows…
Program Evaluation of a School District's Multisensory Reading Initiative
ERIC Educational Resources Information Center
Asip, Michael Patrick
2012-01-01
The purpose of this study was to conduct a formative program evaluation of a school district's multisensory reading initiative. The mixed methods study involved semi-structured interviews, online survey, focus groups, document review, and analysis of extant special education student reading achievement data. Participants included elementary…
The Role of Formative Evaluation in Implementation Research and the QUERI Experience
Stetler, Cheryl B; Legro, Marcia W; Wallace, Carolyn M; Bowman, Candice; Guihan, Marylou; Hagedorn, Hildi; Kimmel, Barbara; Sharp, Nancy D; Smith, Jeffrey L
2006-01-01
This article describes the importance and role of 4 stages of formative evaluation in our growing understanding of how to implement research findings into practice in order to improve the quality of clinical care. It reviews limitations of traditional approaches to implementation research and presents a rationale for new thinking and use of new methods. Developmental, implementation-focused, progress-focused, and interpretive evaluations are then defined and illustrated with examples from Veterans Health Administration Quality Enhancement Research Initiative projects. This article also provides methodologic details and highlights challenges encountered in actualizing formative evaluation within implementation research. PMID:16637954
ERIC Educational Resources Information Center
Hogg, Linda; Yates, Anne
2013-01-01
This formative evaluation within a graduate initial teacher education program sought to identify student teachers' perceptions of lecturer practice and its influence on their developing practice. Data collected from course and teaching evaluations and focus group interviews suggested that microstructural course elements--lectures, tutorials, and…
A Formative Evaluation of the Children, Youth, and Families at Risk Coaching Model
ERIC Educational Resources Information Center
Olson, Jonathan R.; Smith, Burgess; Hawkey, Kyle R.; Perkins, Daniel F.; Borden, Lynne M.
2016-01-01
In this article, we describe the results of a formative evaluation of a coaching model designed to support recipients of funding through the Children, Youth, and Families at Risk (CYFAR) initiative. Results indicate that CYFAR coaches draw from a variety of types of coaching and that CYFAR principle investigators (PIs) are generally satisfied with…
Pitts, Stephanie B Jilcott; Bringolf, Karamie R; Lloyd, Cameron L; McGuirt, Jared T; Lawton, Katherine K; Morgan, Jo
2013-07-18
We examined the feasibility of increasing access to healthful food in corner stores to inform a Communities Putting Prevention to Work (CPPW) initiative by engaging stakeholders (corner store owners and customers) in a formative evaluation. Qualitative interviews were conducted with corner store owners and managers (n = 11). Customer intercept surveys (n = 179) were also conducted with customers of 9 stores. Corner stores were located in rural food deserts (municipalities without a chain supermarket) and in low-income, urban municipalities in eastern North Carolina. Interviews were transcribed verbatim and double-coded. Qualitative themes related to feasibility of increasing access to healthful foods were extracted. Shopping patterns of rural and urban customers were compared by using t tests. Corner store owners were willing to stock more healthful foods, but they perceived that customer demand for these foods was low. Rural customers reported more frequently shopping at corner stores than urban customers and more frequently stated that the reason they do not eat more fruits and vegetables is that the stores in which they shop do not sell them. Most customers reported they would be very or somewhat likely to purchase fresh produce at a corner store. Corner stores may be an important source of food for rural and low-income residents and thus a good place in which to intervene. The results of this formative evaluation were used to plan and evaluate a CPPW healthy corner store initiative.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Lavado, Ramon; Rimoldi, John M.; Schlenk, Daniel
2009-03-01
Previous studies in rainbow trout have shown that acclimation to hypersaline environments enhances the toxicity to thioether organophosphate and carbamate pesticides. In order to determine the role of biotransformation in this process, the metabolism of the thioether organophosphate biocide, fenthion was evaluated in microsomes from gills, liver and olfactory tissues in rainbow trout (Oncorhynchus mykiss) acclimated to freshwater and 17 per mille salinity. Hypersalinity acclimation increased the formation of fenoxon and fenoxon sulfoxide from fenthion in liver microsomes from rainbow trout, but not in gills or in olfactory tissues. NADPH-dependent and independent hydrolysis was observed in all tissues, but onlymore » NADPH-dependent fenthion cleavage was differentially modulated by hypersalinity in liver (inhibited) and gills (induced). Enantiomers of fenthion sulfoxide (65% and 35% R- and S-fenthion sulfoxide, respectively) were formed in liver and gills. The predominant pathway of fenthion activation in freshwater appears to be initiated through initial formation of fenoxon which may be subsequently converted to the most toxic metabolite fenoxon R-sulfoxide. However, in hypersaline conditions both fenoxon and fenthion sulfoxide formation may precede fenoxon sulfoxide formation. Stereochemical evaluation of sulfoxide formation, cytochrome P450 inhibition studies with ketoconazole and immunoblots indicated that CYP3A27 was primarily involved in the enhancement of fenthion activation in hypersaline-acclimated fish with limited contribution of FMO to initial sulfoxidation.« less
Klar, Roland M; Duarte, Raquel; Dix-Peek, Therese; Dickens, Caroline; Ferretti, Carlo; Ripamonti, Ugo
2013-01-01
Coral-derived calcium carbonate/hydroxyapatite macroporous constructs of the genus Goniopora with limited hydrothermal conversion to hydroxyapatite (7% HA/CC) initiate the induction of bone formation. Which are the molecular signals that initiate pattern formation and the induction of bone formation? To evaluate the role of released calcium ions and osteoclastogenesis, 7% HA/CC was pre-loaded with either 500 μg of the calcium channel blocker, verapamil hydrochloride, or 240 μg of the osteoclast inhibitor, biphosphonate zoledronate, and implanted in the rectus abdominis muscle of six adult Chacma baboons Papio ursinus. Generated tissues on days 15, 60 and 90 were analysed by histomorphometry and qRT-PCR. On day 15, up-regulation of type IV collagen characterized all the implanted constructs correlating with vascular invasion. Zoledronate-treated specimens showed an important delay in tissue patterning and morphogenesis with limited bone formation. Osteoclastic inhibition yielded minimal, if any, bone formation by induction. 7% HA/CC pre-loaded with the Ca++ channel blocker verapamil hydrochloride strongly inhibited the induction of bone formation. Down-regulation of bone morphogenetic protein-2 (BMP-2) together with up-regulation of Noggin genes correlated with limited bone formation in 7% HA/CC pre-loaded with either verapamil or zoledronate, indicating that the induction of bone formation by coral-derived macroporous constructs is via the BMPs pathway. The spontaneous induction of bone formation is initiated by a local peak of Ca++ activating stem cell differentiation and the induction of bone formation. PMID:24106923
Development and formative evaluation of the e-Health Implementation Toolkit (e-HIT).
Murray, Elizabeth; May, Carl; Mair, Frances
2010-10-18
The use of Information and Communication Technology (ICT) or e-Health is seen as essential for a modern, cost-effective health service. However, there are well documented problems with implementation of e-Health initiatives, despite the existence of a great deal of research into how best to implement e-Health (an example of the gap between research and practice). This paper reports on the development and formative evaluation of an e-Health Implementation Toolkit (e-HIT) which aims to summarise and synthesise new and existing research on implementation of e-Health initiatives, and present it to senior managers in a user-friendly format. The content of the e-HIT was derived by combining data from a systematic review of reviews of barriers and facilitators to implementation of e-Health initiatives with qualitative data derived from interviews of "implementers", that is people who had been charged with implementing an e-Health initiative. These data were summarised, synthesised and combined with the constructs from the Normalisation Process Model. The software for the toolkit was developed by a commercial company (RocketScience). Formative evaluation was undertaken by obtaining user feedback. There are three components to the toolkit--a section on background and instructions for use aimed at novice users; the toolkit itself; and the report generated by completing the toolkit. It is available to download from http://www.ucl.ac.uk/pcph/research/ehealth/documents/e-HIT.xls. The e-HIT shows potential as a tool for enhancing future e-Health implementations. Further work is needed to make it fully web-enabled, and to determine its predictive potential for future implementations.
Development and formative evaluation of the e-Health Implementation Toolkit (e-HIT)
2010-01-01
Background The use of Information and Communication Technology (ICT) or e-Health is seen as essential for a modern, cost-effective health service. However, there are well documented problems with implementation of e-Health initiatives, despite the existence of a great deal of research into how best to implement e-Health (an example of the gap between research and practice). This paper reports on the development and formative evaluation of an e-Health Implementation Toolkit (e-HIT) which aims to summarise and synthesise new and existing research on implementation of e-Health initiatives, and present it to senior managers in a user-friendly format. Results The content of the e-HIT was derived by combining data from a systematic review of reviews of barriers and facilitators to implementation of e-Health initiatives with qualitative data derived from interviews of "implementers", that is people who had been charged with implementing an e-Health initiative. These data were summarised, synthesised and combined with the constructs from the Normalisation Process Model. The software for the toolkit was developed by a commercial company (RocketScience). Formative evaluation was undertaken by obtaining user feedback. There are three components to the toolkit - a section on background and instructions for use aimed at novice users; the toolkit itself; and the report generated by completing the toolkit. It is available to download from http://www.ucl.ac.uk/pcph/research/ehealth/documents/e-HIT.xls Conclusions The e-HIT shows potential as a tool for enhancing future e-Health implementations. Further work is needed to make it fully web-enabled, and to determine its predictive potential for future implementations. PMID:20955594
Under the Air Quality Model Evaluation International Initiative, Phase 2 (AQMEII-2), three online coupled air quality model simulations, with six different configurations, are analyzed for their performance, inter-model agreement, and responses to emission and meteorological chan...
Development and Formative Evaluation of Computer Simulated College Chemistry Experiments.
ERIC Educational Resources Information Center
Cavin, Claudia S.; Cavin, E. D.
1978-01-01
This article describes the design, preparation, and initial evaluation of a set of computer-simulated chemistry experiments. The experiments entailed the use of an atomic emission spectroscope and a single-beam visible absorption spectrophometer. (Author/IRT)
ERIC Educational Resources Information Center
Brennan, Sue E.; Cumpston, Miranda; Misso, Marie L.; McDonald, Steve; Murphy, Matthew J.; Green, Sally E.
2016-01-01
The Policy Liaison Initiative (PLI) is a long-term knowledge translation initiative designed to support the use of Cochrane systematic reviews in health policy. A joint initiative between the Australasian Cochrane Centre and Australian Government Department of Health and Ageing, the PLI includes: 1) a community of practice for evidence-informed…
Steps toward a Formative Evaluation of NSDL. Technical Report
ERIC Educational Resources Information Center
Bikson, Tora K.; Kalra, Nidhi; Galway, Lionel A.; Agnew, Grace
2011-01-01
The National Science Foundation's (NSF) National Science Digital Library/Distributed Learning (NSDL) program turned 10 years old in 2010. This report presents results of a preliminary program evaluation carried out by RAND and is organized around three principal goals: (1) Provide an initial evaluation of NSDL based on existing information…
Project Change Evaluation Research Brief.
ERIC Educational Resources Information Center
Leiderman, Sally A.; Dupree, David M.
Project Change is a community-driven anti-racism initiative operating in four communities: Albuquerque, New Mexico; El Paso, Texas; Knoxville, Tennessee; and Valdosta, Georgia. The formative evaluation of Project Change began in 1994 when all of the sites were still in planning or early action phases. Findings from the summative evaluation will be…
Williams, Katherine M; Kirsh, Susan; Aron, David; Au, David; Helfrich, Christian; Lambert-Kerzner, Anne; Lowery, Julie; Battaglia, Catherine; Graham, Glenn D; Doukas, Michael; Jain, Rajiv; Ho, P Michael
2017-07-01
Veteran's Affairs Office of Specialty Care (OSC) launched four national initiatives (Electronic-Consults [e-Consults], Specialty Care Access Networks-Extension for Community Healthcare Outcomes [SCAN-ECHO], Mini-Residencies, and Specialty Care Neighborhood) to improve specialty care delivery and funded a center to evaluate the initiatives. The evaluation, guided by two implementation frameworks, provides formative (administrator/provider interviews and surveys) and summative data (quantitative data on patterns of use) about the initiatives to OSC. Evaluation of initiative implementation is assessed through CFIR (Consolidated Framework for Implementation Research)-grounded qualitative interviews to identify barriers/facilitators. Depending on high or low implementation, factors such as receiving workload credit, protected time, existing workflow/systems compatibility, leadership engagement, and access to information/resources were considered implementation barriers or facilitators. Findings were shared with OSC and used to further refine implementation at additional sites. Evaluation of other initiatives is ongoing. The mixed-methods approach has provided timely information to OSC about initiative effect and impacted OSC policies on implementation at additional sites.
Takashina, Hirotsugu; Watanabe, Akira; Tsuneoka, Hiroshi
2017-01-01
To evaluate full-thickness macular hole (MH) formation in the postoperative period after initial vitrectomy for rhegmatogenous retinal detachment (rRD). We retrospectively reviewed the medical records of 4 consecutive eyes that required additional vitrectomy for full-thickness MH between April 2013 and March 2016 after undergoing an initial vitrectomy for rRD. Epiretinal membrane (ERM) was identified by preoperative optical coherence tomography or intraoperative dye staining in each case. Photocoagulation of retinal breaks prior to initial vitrectomy was performed in Cases 1, 2, and 3 (4-16 days), with yttrium-aluminum-garnet capsulotomy after cataract extraction also performed prior to the retinal break formation in Case 3. At the initial vitrectomy, there was a superior retinal break which crossed the equator in Case 2, and an intentional hole was created in Cases 1 and 4. The mean interval from the initial vitrectomy until MH formation was 27.5 ± 15.8 months. As with Case 2, the intervals in Cases 1 and 4, in which an intentional hole was created, were clearly shorter than in those in Case 3. Finally, MH closure was achieved after an additional vitrectomy (removal of the internal limiting membrane with ERM and gas tamponade) and best-corrected visual acuity improved in each case. ERM was identified in the cases examined in our study. The presence of an intentional hole might shorten the interval of MH formation after vitrectomy for rRD.
Developmental evaluation and the 'Stronger Economies Together' initiative in the United States.
Honadle, Beth Walter; Zapata, Marisa A; Auffrey, Christopher; vom Hofe, Rainer; Looye, Johanna
2014-04-01
This article describes a developmental evaluation and explains its impact on the Stronger Economies Together (SET) initiative of the U.S. Department of Agriculture in collaboration with the Nation's four Regional Rural Development Centers and Land-Grant universities. Through a dynamic process, this evaluation of the early phases of an initiative led to continuous program alterations based on feedback. The relationship of the evaluation team to the initiative's coordinating team enabled seamless transfer of observations, suggestions, and recommendations to decision makers. The multidisciplinary character of the evaluation team provided a diverse set of perspectives with a depth of subject matter and knowledge from relevant fields. One lesson is that developmental evaluators must be flexible, nimble, creative, and adaptive. When expected data are imperfect or nonexistent, the team must collect alternate information and make recommendations to improve data collection. As the initiative proceeded and modifications came about, the evaluation team had to recognize the changes in the program and focus on different questions. This experience with developmental evaluation provides insights into how interdisciplinary teams may need to change course and conduct a developmental evaluation when a formative evaluation was originally envisioned. Published by Elsevier Ltd.
An Unexpected Benefit of Formative Student Evaluations
ERIC Educational Resources Information Center
Aultman, Lori Price
2006-01-01
The issue of student evaluations of faculty has been a source of debate in higher education for many years (Arden 2002; McKeachie 1979; Ory 2001; Trout 2000). Nevertheless, this author believes that student evaluations can be a valuable source of feedback for improving the quality of instruction. Therefore, she decided to initiate the practice of…
Critical Fusion--Technology and Equity in Secondary Education
ERIC Educational Resources Information Center
Magolda, Peter
2006-01-01
This manuscript reports on the first year of a formative, external program evaluation of the Critical Fusion Initiative (CFI), which involved a higher education institution, a public high school, a corporation, and two nonprofit organizations. The initiative fused technology and education to address the issue of equity by assisting 16 high school…
Nakamura, M; Saito, K; Wakabayashi, M
1990-04-01
The purpose of this study was to investigate how attitude change is generated by the recipient's degree of attitude formation, evaluative-emotional elements contained in the persuasive messages, and source expertise as a peripheral cue in the persuasion context. Hypotheses based on the Attitude Formation Theory of Mizuhara (1982) and the Elaboration Likelihood Model of Petty and Cacioppo (1981, 1986) were examined. Eighty undergraduate students served as subjects in the experiment, the first stage of which involving manipulating the degree of attitude formation with respect to nuclear power development. Then, the experimenter presented persuasive messages with varying combinations of evaluative-emotional elements from a source with either high or low expertise on the subject. Results revealed a significant interaction effect on attitude change among attitude formation, persuasive message and the expertise of the message source. That is, high attitude formation subjects resisted evaluative-emotional persuasion from the high expertise source while low attitude formation subjects changed their attitude when exposed to the same persuasive message from a low expertise source. Results exceeded initial predictions based on the Attitude Formation Theory and the Elaboration Likelihood Model.
2014-11-01
Integrated Cognitive-neuroscience Architectures for Understanding Sensemaking (ICArUS): Phase 1 Test and Evaluation Development Guide Craig...Self-initiated sensemaking ........................................................................................... 19 Feature Vector Format: Tasks...The Integrated Cognitive-neuroscience Architectures for Understanding Sensemaking (ICArUS) Program aimed to build computational cognitive
USDA-ARS?s Scientific Manuscript database
Adherence of Enterohemorrhagic Escherichia coli (EHEC) O157:H7 to biotic (epithelial cells) and abiotic surfaces (biofilm formation) proceeds from an initial reversible adherence to an irreversible stage of intimate adherence. While flagella and fimbriae facilitate initial stage of adherence in both...
ERIC Educational Resources Information Center
McAnaney, Donal F.; Wynne, Richard F.
2016-01-01
A key challenge in formative evaluation is to gather appropriate evidence to inform the continuous improvement of initiatives. In the absence of outcome data, the programme evaluator often must rely on the perceptions of beneficiaries and staff in generating insight into what is making a difference. The article describes the approach adopted in an…
Scanlon, Dennis P; Alexander, Jeffrey A; Beich, Jeff; Christianson, Jon B; Hasnain-Wynia, Romana; McHugh, Megan C; Mittler, Jessica N; Shi, Yunfeng; Bodenschatz, Laura J
2012-09-01
The Aligning Forces for Quality (AF4Q) initiative is the Robert Wood Johnson Foundation's (RWJF's) signature effort to increase the overall quality of healthcare in targeted communities throughout the country. In addition to sponsoring this 16-site, complex program, the RWJF funds an independent scientific evaluation to support objective research on the initiative's effectiveness and contributions to basic knowledge in 5 core programmatic areas. The research design, data, and challenges faced in the evaluation of this 10-year initiative are discussed. A descriptive overview of the evaluation research design for a multi-site, community based, healthcare quality improvement initiative is provided. The multiphase research design employed by the evaluation team is discussed. Evaluation provides formative feedback to the RWJF, participants, and other interested audiences in real time; develops approaches to assess innovative and under-studied interventions; furthers the analysis and understanding of effective community-based collaborative work in healthcare; and helps to differentiate the various facilitators, barriers, and contextual dimensions that affect the implementation and outcomes of community-based health interventions. The AF4Q initiative is arguably the largest community-level healthcare improvement demonstration in the United States to date; it is being implemented at a time of rapid change in national healthcare policy. The implementation of large-scale, multi-site initiatives is becoming an increasingly common approach for addressing problems in healthcare. The evaluation research design for the AF4Q initiative, and the lessons learned from its approach, may be valuable to others tasked with evaluating similar community-based initiatives.
Utilizing Evaluation To Develop a Marketing Strategy in the Louisiana Cooperative Extension Service.
ERIC Educational Resources Information Center
Coreil, Paul D.; Verma, Satish
Marketing has become a popular strategic initiative among state extension services to meet the growing demand for program accountability. The Louisiana Cooperative Extension Service (LCES) began a formative evaluation of its marketing efforts as a step toward a comprehensive marketing plan. All extension faculty were surveyed to determine their…
ERIC Educational Resources Information Center
Flaherty, John, Jr.; Sobolew-Shubin, Alexandria; Heredia, Alberto; Chen-Gaddini, Min; Klarin, Becca; Finkelstein, Neal D.
2014-01-01
Math in Common® (MiC) is a five-year initiative that supports a formal network of 10 California school districts as they implement the Common Core State Standards in mathematics (CCSS-M) across grades K-8. As the MiC initiative moves into its second year, one of the central activities that each of the districts is undergoing to support CCSS…
Mostyn, Alison; Meade, Oonagh; Lymn, Joanne S
2012-11-13
The use of anonymous audience response technology (ART) to actively engage students in classroom learning has been evaluated positively across multiple settings. To date, however, there has been no empirical evaluation of the use of individualised ART handsets and formative feedback of ART scores. The present study investigates student perceptions of such a system and the relationship between formative feedback results and exam performance. Four successive cohorts of Non-Medical Prescribing students (n=107) had access to the individualised ART system and three of these groups (n=72) completed a questionnaire about their perceptions of using ART. Semi-structured interviews were carried out with a purposive sample of seven students who achieved a range of scores on the formative feedback. Using data from all four cohorts of students, the relationship between mean ART scores and summative pharmacology exam score was examined using a non-parametric correlation. Questionnaire and interview data suggested that the use of ART enhanced the classroom environment, motivated students and promoted learning. Questionnaire data demonstrated that students found the formative feedback helpful for identifying their learning needs (95.6%), guiding their independent study (86.8%), and as a revision tool (88.3%). Interviewees particularly valued the objectivity of the individualised feedback which helped them to self-manage their learning. Interviewees' initial anxiety about revealing their level of pharmacology knowledge to the lecturer and to themselves reduced over time as students focused on the learning benefits associated with the feedback.A significant positive correlation was found between students' formative feedback scores and their summative pharmacology exam scores (Spearman's rho = 0.71, N=107, p<.01). Despite initial anxiety about the use of individualised ART units, students rated the helpfulness of the individualised handsets and personalised formative feedback highly. The significant correlation between ART response scores and student exam scores suggests that formative feedback can provide students with a useful reference point in terms of their level of exam-readiness.
Genetic and Phenotypic Analysis of Lateral Root Development in Arabidopsis thaliana.
Napsucialy-Mendivil, Selene; Dubrovsky, Joseph G
2018-01-01
Root system formation to a great extent depends on lateral root (LR) formation. In Arabidopsis thaliana, LRs are initiated within a parent root in pericycle that is an external tissue of the stele. LR initiation takes place in a strictly acropetal pattern, whereas posterior lateral root primordium (LRP) formation is asynchronous. In this chapter, we focus on methods of genetic and phenotypic analysis of LR initiation, LRP morphogenesis, and LR emergence in Arabidopsis. We provide details on how to make cleared root preparations and how to identify the LRP stages. We also pay attention to the categorization of the LRP developmental stages and their variations and to the normalization of the number of LRs and LRPs formed, per length of the primary root, and per number of cells produced within a root. Hormonal misbalances and mutations affect LRP morphogenesis significantly, and the evaluation of LRP abnormalities is addressed as well. Finally, we deal with various molecular markers that can be used for genetic and phenotypic analyses of LR development.
Shin, Marlena H; Rivard, Peter E; Shwartz, Michael; Borzecki, Ann; Yaksic, Enzo; Stolzmann, Kelly; Zubkoff, Lisa; Rosen, Amy K
2018-02-14
Given that patient safety measures are increasingly used for public reporting and pay-for performance, it is important for stakeholders to understand how to use these measures for improvement. The Agency for Healthcare Research and Quality (AHRQ) Patient Safety Indicators (PSIs) are one particularly visible set of measures that are now used primarily for public reporting and pay-for-performance among both private sector and Veterans Health Administration (VA) hospitals. This trend generates a strong need for stakeholders to understand how to interpret and use the PSIs for quality improvement (QI). The goal of this study was to develop an educational program and tailor it to stakeholders' needs. In this paper, we share what we learned from this program development process. Our study population included key VA stakeholders involved in reviewing performance reports and prioritizing and initiating quality/safety initiatives. A pre-program formative evaluation through telephone interviews and web-based surveys assessed stakeholders' educational needs/interests. Findings from the formative evaluation led to development and implementation of a cyberseminar-based program, which we tailored to stakeholders' needs/interests. A post-program survey evaluated program participants' perceptions about the PSI educational program. Interview data confirmed that the concepts we had developed for the interviews could be used for the survey. Survey results informed us on what program delivery mode and content topics were of high interest. Six cyberseminars were developed-three of which focused on two content areas that were noted of greatest interest: learning how to use PSIs for monitoring trends and understanding how to interpret PSIs. We also used snapshots of VA PSI reports so that participants could directly apply learnings. Although initial interest in the program was high, actual attendance was low. However, post-program survey results indicated that perceptions about the program were positive. Conducting a formative evaluation was a highly important process in program development. The useful information that we collected through the interviews and surveys allowed us to tailor the program to stakeholders' needs and interests. Our experiences, particularly with the formative evaluation process, yielded valuable lessons that can guide others when developing and implementing similar educational programs.
Yuan, Jun; Zhang, Nan; Huang, Qiwei; Raza, Waseem; Li, Rong; Vivanco, Jorge M.; Shen, Qirong
2015-01-01
The successful colonization of plant growth promoting rhizobacteria (PGPR) in the rhizosphere is an initial and compulsory step in the protection of plants from soil-borne pathogens. Therefore, it is necessary to evaluate the role of root exudates in the colonization of PGPR. Banana root exudates were analyzed by high pressure liquid chromatography (HPLC) which revealed exudates contained several organic acids (OAs) including oxalic, malic and fumaric acid. The chemotactic response and biofilm formation of Bacillus amyloliquefaciens NJN-6 were investigated in response to OA’s found in banana root exudates. Furthermore, the transcriptional levels of genes involved in biofilm formation, yqxM and epsD, were evaluated in response to OAs via quantitative reverse transcriptase polymerase chain reaction (qRT-PCR). Results suggested that root exudates containing the OAs both induced the chemotaxis and biofilm formation in NJN-6. In fact, the strongest chemotactic and biofilm response was found when 50 μM of OAs were applied. More specifically, malic acid showed the greatest chemotactic response whereas fumaric acid significantly induced biofilm formation by a 20.7–27.3% increase and therefore biofilm formation genes expression. The results showed banana root exudates, in particular the OAs released, play a crucial role in attracting and initiating PGPR colonization on the host roots. PMID:26299781
[Control on products of NDMA degradation by UV/O3].
Xu, Bing-bing; Chen, Zhong-lin; Qi, Fei; Yang, Lei; Huang, Lu-xi
2008-12-01
Comparison experiments of two advanced oxidation processes, UV/O3 and UV/H2O2, were carried out to evaluate their degradation effect of N-nitrosodimethylamine (NDMA) and controlling effect of dimethylamine (DMA) formation. The results showed that UV/H2O2 could enhance NDMA degradation, but could not control on the formation of DMA. UV/O3 was not only effective for NDMA degradation, but also was good at controlling on DMA formation. Furthermore, factors affecting the formation of DMA during degradation of NDMA by UV/O3 were studied. The formation of DMA decreased with O3 dosage increasing and DMA was 0.98 mg x L(-1) with 7.7 mg x L(-1) NDMA and 6.64 mg x L(-1) O3 dose. Solution pH had obvious effect on controlling of DMA formation during degradation of NDMA by UV/O3 . The formation of DMA lightly increased with pH increasing from acid to neutral but dramatically decreased in basic aqueous solution. The formation of DMA was only 0.3 mg x L(-1) when the initial concentration of NDMA was 7.7 mg x L(-1) under pH = 11.0 condition. UV/O3 had better controlling of DMA formation with lesser initial concentration of NDMA.
NASA Astrophysics Data System (ADS)
Prikryl, Richard; Lokajíček, Tomáš
2017-04-01
According to previous studies, evaluation of stress-strain behaviour (in uniaxial compression) of various rocks appears to be effective tool allowing for prediction of resistance of natural stone to some physical weathering processes. Precise determination of critical thresholds, specifically of 'crack initiation' and 'crack damage' is fundamental issue in this approach. In contrast to 'crack damage stress/strain threshold', which can be easily read from deflection point on volumetric curve, detection of 'crack initiation' is much more difficult. Besides previously proposed mathematical processing of axial stress-strain curve, recording of acoustic emission (AE) data and their processing provide direct measure of various stress/strain thresholds, specifically of 'crack initiation'. This specific parameter is required during successive computation of energetic parameters (mechanical work), that can be stored by a material without formation of new defects (microcracks) due to acting stress. Based on our experimental data, this mechanical work seems to be proportional to the resistance of a material to formation of mode I (tensile) cracks that are responsible for destruction of subsurface below exposed faces of natural stone.
Time Sequence Evaluation of Biliary Stent Occlusion by Dissection Analysis of Retrieved Stents.
Kwon, Chang-Il; Gromski, Mark A; Sherman, Stuart; Easler, Jeffrey J; El Hajj, Ihab I; Watkins, James; Fogel, Evan L; McHenry, Lee; Lehman, Glen A
2016-08-01
Multiple factors can affect the occlusion of plastic stents. Previous data demonstrate that side holes may induce more biofilm formation probably via microturbulence and bile flow disturbances that could lead to occlusion. These results, however, have not been replicated in subsequent clinical studies with different methods. The objective of this study is to evaluate the physical characteristics of plastic stent occlusion over time. This is a plastic stent sequential analysis study. Biliary stents removed via ERCP from February 24, 2015, to June 2, 2015, were included. One hundred and forty-eight retrieved straight-type plastic stents were longitudinally cut by a custom-made cutting device. These dissected stents were then evaluated in detail with regard to the location of stent occlusion and the stent patency period. Location of stent occlusive debris was the primary outcome in this study. Biofilm formations and occlusions by debris were sequentially but separately tallied. Biofilm formations were initially seen around the side hole areas within 30 days and spread to the entire stent by 60 days. Then, occlusion process by debris was mainly initiated by 80 days and progressed to full occlusion by median of 90 days. Although some occlusions were also observed around the side hole areas within 30 days, affected areas were more widely observed after biofilm formation. This study is the first to attempt to describe the distribution of stent occlusions over time. These observations may help guide future stent development.
Tailoring risk communication to improve comprehension: Do patient preferences help or hurt?
Barnes, Andrew J; Hanoch, Yaniv; Miron-Shatz, Talya; Ozanne, Elissa M
2016-09-01
Risk communication tools can facilitate patients' understanding of risk information. In this novel study, we examine the hypothesis that risk communication methods tailored to individuals' preferences can increase risk comprehension. Preferences for breast cancer risk formats, and risk comprehension data were collected using an online survey from 361 women at high risk for breast cancer. Women's initial preferences were assessed by asking them which of the following risk formats would be the clearest: (a) percentage, (b) frequency, (c) bar graph, (d) pictogram, and (e) comparison to other women. Next, women were presented with 5 different formats for displaying cancer risks and asked to interpret the risk information presented. Finally, they were asked again which risk format they preferred. Initial preferences for risk formats were not associated with risk comprehension scores. However, women with lower risk comprehension scores were more likely to update their risk format preferences after they evaluated risks in different formats. Less numerate women were more likely to prefer graphical rather than numeric risk formats. Importantly, we found that women preferring graphical risk formats had lower risk comprehension in these formats compared to numeric formats. In contrast, women preferring numeric formats performed equally well across formats. Our findings suggest that tailoring risk communication to patient preferences may not improve understanding of medical risks, particularly for less numerate women, and point to the potential perils of tailoring risk communication formats to patient preferences. (PsycINFO Database Record (c) 2016 APA, all rights reserved).
Mager, Diana R; Kazer, Meredith W; Conelius, Jaclyn; Shea, Joyce; Lippman, Doris T; Torosyan, Roben; Nantz, Kathryn
2014-06-03
For many years, an area of research in higher education has been emerging around the development and implementation of fair and effective peer evaluation programs. Recently, a new body of knowledge has developed regarding the development and implementation of fair and effective peer evaluation programs resulting in formative and summative evaluations. The purpose of this article is to describe the development, implementation, and evaluation of a peer review of teaching (PRoT) program for nursing faculty, initiated at one small comprehensive university in the northeastern United States. Pairs of nursing faculty evaluated each other's teaching, syllabi, and course materials after collaborating in a pre-evaluation conference to discuss goals of the classroom visit. Qualitative data gathered in post project focus groups revealed that faculty found their modified PRoT process to be a mutually beneficial experience that was more useful, flexible and collegial, and less stressful than their previous evaluation process.
Evaluation of the Initiation/Promotion Potential of CTFE Trimer Acid
1990-11-01
0 1 0 0 0 0 0 0 0 Atrophic hepatic cords 3 Cc Cc Cc Cc Cc Cc Cc 3 0e Ce Ce 0e Ge 0e Ce Steatosis 3 2 4 4 4 4 4 3 2 1 0 2 2 1 2 1 Kuppfercell pigment...with the formation of hepatic tumors. Therefore, the present study was designed to evaluate CTFE trimer acid for both tumor initiation and promoting...oxidation of palmitoyl coenzyme A (CoA) MOelRaso, unpublished findings). Many compounds cause an increase in the number of hepatic peroxisomes and are
The Formation of Implicit and Explicit Attitudes for Neutral and Valenced Stimuli Using the Self
ERIC Educational Resources Information Center
Perugini, Marco; Richetin, Juliette; Zogmaister, Cristina
2012-01-01
In Evaluative Conditioning (EC) studies, novel Conditioned Stimuli (CSs) are usually selected so to be neutral. However, in real life, because of the tendency of humans to evaluate novel stimuli automatically, novel CSs are very often initially valenced. From the literature little is known on whether EC can be successful under these conditions. In…
Ito, Kazunari; Gomi, Katsuya; Kariyama, Masahiro; Miyake, Tsuyoshi
2017-07-01
The construction of an experimental system that can mimic koji making in the manufacturing setting of a sake brewery is initially required for the quantitative evaluation of mycelia grown on/in koji pellets (haze formation). Koji making with rice was investigated with a solid-state fermentation (SSF) system using a non-airflow box (NAB), which produced uniform conditions in the culture substrate with high reproducibility and allowed for the control of favorable conditions in the substrate during culture. The SSF system using NAB accurately reproduced koji making in a manufacturing setting. To evaluate haze formation during koji making, surfaces and cross sections of koji pellets obtained from koji making tests were observed using a digital microscope. Image analysis was used to distinguish between haze and non-haze sections of koji pellets, enabling the evaluation of haze formation in a batch by measuring the haze rate of a specific number of koji pellets. This method allowed us to obtain continuous and quantitative data on the time course of haze formation. Moreover, drying koji during the late stage of koji making was revealed to cause further penetration of mycelia into koji pellets (internal haze). The koji making test with the SSF system using NAB and quantitative evaluation of haze formation in a batch by image analysis is a useful method for understanding the relations between haze formation and koji making conditions. Copyright © 2017 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.
Guide to conducting tinnitus retraining therapy initial and follow-up interviews.
Henry, James A; Jastreboff, Margaret M; Jastreboff, Pawel J; Schechter, Martin A; Fausti, Stephen A
2003-01-01
Tinnitus Retraining Therapy (TRT) is a structured method of tinnitus treatment that has been performed since 1990. The TRT Initial Interview form was developed to guide clinicians in obtaining essential information from patients that would specify treatment needs. The TRT Follow-up Interview form is similar to the initial interview form and is designed to evaluate outcomes of treatment. The clinician administers these forms verbally. The forms have been used in a highly abbreviated format with the potential for inconsistent interview administration between examiners. This project was to expand the forms to provide specific wording for each question. The expanded forms are presented in this article, and the intent of each question is explained. Standardized administration of these interview forms will facilitate greater uniformity in the initial evaluation and outcomes analyses of patients treated with TRT.
2012-01-01
Background The use of anonymous audience response technology (ART) to actively engage students in classroom learning has been evaluated positively across multiple settings. To date, however, there has been no empirical evaluation of the use of individualised ART handsets and formative feedback of ART scores. The present study investigates student perceptions of such a system and the relationship between formative feedback results and exam performance. Methods Four successive cohorts of Non-Medical Prescribing students (n=107) had access to the individualised ART system and three of these groups (n=72) completed a questionnaire about their perceptions of using ART. Semi-structured interviews were carried out with a purposive sample of seven students who achieved a range of scores on the formative feedback. Using data from all four cohorts of students, the relationship between mean ART scores and summative pharmacology exam score was examined using a non-parametric correlation. Results Questionnaire and interview data suggested that the use of ART enhanced the classroom environment, motivated students and promoted learning. Questionnaire data demonstrated that students found the formative feedback helpful for identifying their learning needs (95.6%), guiding their independent study (86.8%), and as a revision tool (88.3%). Interviewees particularly valued the objectivity of the individualised feedback which helped them to self-manage their learning. Interviewees’ initial anxiety about revealing their level of pharmacology knowledge to the lecturer and to themselves reduced over time as students focused on the learning benefits associated with the feedback. A significant positive correlation was found between students’ formative feedback scores and their summative pharmacology exam scores (Spearman’s rho = 0.71, N=107, p<.01). Conclusions Despite initial anxiety about the use of individualised ART units, students rated the helpfulness of the individualised handsets and personalised formative feedback highly. The significant correlation between ART response scores and student exam scores suggests that formative feedback can provide students with a useful reference point in terms of their level of exam-readiness. PMID:23148762
ERIC Educational Resources Information Center
Perry, Rebecca R.; Seago, Nanette M.; Burr, Elizabeth; Broek, Marie; Finkelstein, Neal D.
2015-01-01
Math in Common® (MiC) is a five-year initiative that supports a formal network of 10 California school districts as they implement the Common Core State Standards in Mathematics (CCSS-M) across grades K-8. This research brief explores how best to select or develop and use classroom observation systems in order to document instructional shifts and…
Setting priorities for space research: An experiment in methodology
NASA Technical Reports Server (NTRS)
1995-01-01
In 1989, the Space Studies Board created the Task Group on Priorities in Space Research to determine whether scientists should take a role in recommending priorities for long-term space research initiatives and, if so, to analyze the priority-setting problem in this context and develop a method by which such priorities could be established. After answering the first question in the affirmative in a previous report, the task group set out to accomplish the second task. The basic assumption in developing a priority-setting process is that a reasoned and structured approach for ordering competing initiatives will yield better results than other ways of proceeding. The task group proceeded from the principle that the central criterion for evaluating a research initiative must be its scientific merit -- the value of the initiative to the proposing discipline and to science generally. The group developed a two-stage methodology for priority setting and constructed a procedure and format to support the methodology. The first of two instruments developed was a standard format for structuring proposals for space research initiatives. The second instrument was a formal, semiquantitative appraisal procedure for evaluating competing proposals. This report makes available complete templates for the methodology, including the advocacy statement and evaluation forms, as well as an 11-step schema for a priority-setting process. From the beginning of its work, the task group was mindful that the issue of priority setting increasingly pervades all of federally supported science and that its work would have implications extending beyond space research. Thus, although the present report makes no recommendations for action by NASA or other government agencies, it provides the results of the task group's work for the use of others who may study priority-setting procedures or take up the challenge of implementing them in the future.
Corn, Jenifer O; Byrom, Elizabeth; Knestis, Kirk; Matzen, Nita; Thrift, Beth
2012-11-01
Schools, districts, and state-level educational organizations are experiencing a great shift in the way they do the business of education. This shift focuses on accountability, specifically through the expectation of the effective utilization of evaluative-focused efforts to guide and support decisions about educational program implementation. In as much, education leaders need specific guidance and training on how to plan, implement, and use evaluation to critically examine district and school-level initiatives. One specific effort intended to address this need is through the Capacity for Applying Project Evaluation (CAPE) framework. The CAPE framework is composed of three crucial components: a collection of evaluation resources; a professional development model; and a conceptual framework that guides the work to support evaluation planning and implementation in schools and districts. School and district teams serve as active participants in the professional development and ultimately as formative evaluators of their own school or district-level programs by working collaboratively with evaluation experts. The CAPE framework involves the school and district staff in planning and implementing their evaluation. They are the ones deciding what evaluation questions to ask, which instruments to use, what data to collect, and how and to whom results should be reported. Initially this work is done through careful scaffolding by evaluation experts, where supports are slowly pulled away as the educators gain experience and confidence in their knowledge and skills as evaluators. Since CAPE engages all stakeholders in all stages of the evaluation, the philosophical intentions of these efforts to build capacity for formative evaluation strictly aligns with the collaborative evaluation approach. Copyright © 2012 Elsevier Ltd. All rights reserved.
The Schladitz Fuel Injector: An Initial Performance Evaluation without Burning.
1982-03-01
same heating rate in the absence of the exit nozzle. Stated alternatively , the presence of the downstream nozzle reduced the required heat addition...rate by about one-third for formation of a spray having 50% or more mist content. It was further noted that this heating rate reduction was essentially...plot for Jet-A fuel suggests that the creation of a fine mist by the SFI in the absence of any downstream nozzle is accompanied by the formation of a
Collisional and dynamical processes in moon and planet formation
NASA Technical Reports Server (NTRS)
1979-01-01
The collisional and dynamical processes in moon and planet formation are discussed. A hydrodynamic code of collision calculations, the orbital element changes due to gravitational scattering, a validation of the mass shifting algorithm, a theory of rotations, and the origin of asteroids are studied. A numerical model of planet growth is discussed and a methodology to evaluate the rate at which megaregolith increases its depth as a function of total accumulate number of impacts on an initially smooth, coherent surface is described.
Gøtterup, Jacob; Olsen, Karsten; Knøchel, Susanne; Tjener, Karsten; Stahnke, Louise H; Møller, Jens K S
2008-04-01
Three Staphylococcus strains, S. carnosus, S. simulans and S. saprophyticus, selected due to their varying nitrite and/or nitrate-reductase activities, were used to initiate colour formation during sausage fermentation. During fermentation of sausages with either nitrite or nitrate added, colour was followed by L(∗)a(∗)b measurements and the content of nitrosylmyoglobin (MbFe(II)NO) quantified by electron spin resonance (ESR). MbFe(II)NO was rapidly formed in sausages with added nitrite independent of the presence of nitrite reducing bacteria, whereas the rate of MbFe(II)NO formation in sausages with added nitrate depended on the specific Staphylococcus strain. Strains with high nitrate-reductase activity showed a significantly faster rate of pigment formation, but other factors were of influence as well. Product stability for the sliced, packaged sausage was evaluated as surface colour and oxidation by autofluorescence and hexanal content, respectively. No significant direct effect of the Staphylococcus addition was observed, however, there was a clear correspondence between high initial amount of MbFe(II)NO in the different sausages and the colour stability during storage. Autofluorescence data correlated well with hexanal content, and may be used as predictive tools. Overall, nitrite- and nitrate-reductase activities of Staphylococcus strains in nitrite-cured sausages were of limited importance regarding colour development, while in nitrate-cured sausages strains with higher nitrate reductase activity were crucial for ensuring optimal colour formation during initial fermentation stages.
Sawatsky, Adam P; Berlacher, Kathryn; Granieri, Rosanne
2014-07-01
The traditional lecture is used by many residency programs to fulfill the mandate for regular didactic sessions, despite limited evidence to demonstrate its effectiveness. Active teaching strategies have shown promise in improving medical knowledge but have been challenging to implement within the constraints of residency training. We developed and evaluated an innovative structured format for interactive teaching within the residency noon conference. We developed an ACTIVE teaching format structured around the following steps: assemble (A) into groups, convey (C) learning objectives, teach (T) background information, inquire (I) through cases and questions, verify (V) understanding, and explain (E) answer choices and educate on the learning points. We conducted a prospective, controlled study of the ACTIVE teaching format versus the standard lecture format, comparing resident satisfaction, immediate knowledge achievement and long-term knowledge retention. We qualitatively assessed participating faculty members' perspectives on the faculty development efforts and the feasibility of teaching using the ACTIVE format. Sixty-nine internal medicine residents participated in the study. Overall, there was an improvement in perceived engagement using the ACTIVE teaching format (4.78 vs. 3.80, P < 0.01), with no increase in stress or decrement in break time. There was an improvement in initial knowledge achievement with the ACTIVE teaching format (overall absolute score increase of 11%, P = 0.04) and a trend toward improvement in long-term knowledge retention. Faculty members felt adequately prepared to use the ACTIVE teaching format, and enjoyed teaching with the ACTIVE teaching format more than the standard lecture. A structured ACTIVE teaching format improved resident engagement and initial knowledge, and required minimal resources. The ACTIVE teaching format offers an exciting alternative to the standard lecture for resident noon conference and is easy to implement.
Interdisciplinary Collaboration Supporting Social-Emotional Learning in Rural School Systems
ERIC Educational Resources Information Center
Meyers, Adena B.; Tobin, Renée M.; Huber, Brenda J.; Conway, Dawn E.; Shelvin, Kristal H.
2015-01-01
In this article we illustrate the roles of school psychologists, administrators, social workers, teachers, and parents in school reform by describing the adoption, initial implementation, and formative evaluation of an evidence-based social and emotional learning (SEL) program within several rural Midwestern school districts in a geographically…
NASA Technical Reports Server (NTRS)
Chafin, R. L.; Martin, T. H.
1980-01-01
The project plan was to hold focus groups to identify the factors influencing the ease of use characteristics of software and to bond the problem. A questionnaire survey was conducted to evaluate those factors which were more appropriately measured with that method. The performance oriented factors were analyzed and relationships hypothesized. The hypotheses were put to test in the experimental phase of the project. In summary, the initial analysis indicates that there is an initial performance effect favoring computer controlled dialogue but the advantage fades fast as operators become experienced. The user documentation style is seen to have a significant effect on performance. The menu and prompt command formats are preferred by inexperienced operators. The short form mnemonic is least favored. There is no clear best command format but the short form mnemonic is clearly the worst.
Bioactivity of gelatin coated magnetic iron oxide nanoparticles: in vitro evaluation.
Gaihre, Babita; Khil, Myung Seob; Kang, Hyo Kyoung; Kim, Hak Yong
2009-02-01
Current research explores formation of bone like apatite on gelatin coated magnetic iron oxide nanoparticles (GIOPs) to evaluate the bioactivity of the material. The GIOPs were soaked in simulated body fluid (SBF) and the apatite formation on the surface was investigated in regular interval of time. Fourier transform-infrared (FT-IR) and x-ray diffraction spectroscopic (XRD) analyses were done to investigate the chemical changes and field emission-scanning electron microscopic (FE-SEM) analysis was done to investigate the morphological changes occurring on the surface of the GIOPs after soaking in different time intervals. The kinetic studies of the apatite growth in SBF suggest that initially calcium and phosphorous ions were deposited to the surface of the GIOPs from the SBF leading to formation of amorphous Ca/P particles. Later, after 9 days of the incubation the amorphous particles were fused to form needle and blade like crystalline structures of bone like apatite.
Kręcisz, Magdalena; Wójtowicz, Agnieszka
2017-01-01
For consumers suffering with gluten intolerance, the only way to manage the condition is to avoid foods which are high in gluten. Instant gruels, processed from gluten-free corn and rice by extrusion cooking, could be used as a ready meal both for children and for adults on a gluten-free diet. The aim of the study was to evaluate the effects of various processing conditions on selected characteristics of corn-rice instant gruels. Corn-rice mixtures (75:25 and 50:50) were processed at 12, 14, 16 and 18% of initial moisture content, using an extruder with screw speeds of 80, 100 and 120 rpm. Bulk density, water absorption and solubility, gel formation, color and sensory characteristics were assessed, under various pro- cessing conditions and with various corn:rice ratios. The composition of the raw materials, initial moisture content and screw speed applied during processing affected the characteristics of the corn-rice extruded instant gruels. Increasing the amount of rice in the recipe from 25 to 50% resulted in decreased bulk density, water solubility, volumetric gel formation ability and b* value. Increasing the initial moisture content increased the bulk density, L*, a* and b* intensity, and gel formation index values of extrudates made with a 75:25 corn-rice recipe. Increased rpm increased extrudate solubility and water absorption, if the initial moisture content was higher than 14%. The highest scores for overall acceptability were found for milk suspensions of 75:25 and 50:50 corn-rice instant gruels processed at 12 and 14% of initial moisture content, at 120 rpm. Corn-rice instant gruels can be successfully produced by extrusion-cooking. Variable param- eters, like the initial moisture content of raw materials or screw speed during processing significantly affected the properties of the products. An understanding of the effects of processing conditions on some qualities of extruded instant gruels allows more desirable products to be created. Moreover, the various components can be used for extruded products for consumers on gluten-free diets. Functional additives incorporated in the recipe to improve the nutritional value of the extrudates, which will be investigated in our upcoming research.
Ferreira Ribeiro, Cyntia; Cogo-Müller, Karina; Franco, Gilson Cesar; Silva-Concílio, Laís Regiane; Sampaio Campos, Márcia; de Mello Rode, Sigmar; Claro Neves, Ana Christina
2016-09-01
The aim of this study was to examine in vivo the initial bacterial adhesion on titanium implants with different surface treatments. Ten subjects wore oral splints containing machined pure titanium disks (Ti-M), acid-etched titanium (Ti-AE) and anodized and laser irradiated disks (Ti-AL) for 24h. After this period, disks were removed from the splints and adherent bacteria were quantified by an enzymatic assay to assess total viable bacteria and by Real Time PCR to evaluate total bacteria and Streptococcus oralis levels. Additionally, the initial adherent microorganisms were visualized by scanning electron microscopy (SEM). Titanium surface morphology was verified using SEM, and roughness was evaluated by profilometer analysis. Regarding titanium surface roughness, Ti-AL (1.423±0.397) showed significantly higher Ra values than did Ti-M (0.771±0.182) and Ti-AE (0.735±0.196) (p<0.05, ANOVA - Tahame). Ti-AE and Ti-AL presented roughened micro-structure surfaces characterized by open pores, whereas Ti-M showed long grooves alternating with planed areas. Comparing the Ti-M, Ti-AE and Ti-AL groups for viable bacteria (MTT assay), total bacteria and S. oralis quantification (qPCR), no significant differences were observed among these three groups (p>0.05, ANOVA - Tahame). SEM images showed similar bacterial adhesion on the three titanium surfaces, predominantly characterized by cocci and several bacilli, indicating an initial colonization of the oral biofilm. In conclusion, roughness and microtopography did not stimulate initial biofilm formation on titanium surfaces with different surface treatments. Copyright © 2016 Elsevier Ltd. All rights reserved.
The interaction of rhinal cortex and hippocampus in human declarative memory formation.
Fell, Jürgen; Klaver, Peter; Elger, Christian E; Fernández, Guillén
2002-01-01
Human declarative memory formation crucially depends on processes within the medial temporal lobe (MTL). These processes can be monitored in real-time by recordings from depth electrodes implanted in the MTL of patients with epilepsy who undergo presurgical evaluation. In our studies, patients performed a word memorization task during depth EEG recording. Afterwards, the difference between event-related potentials (ERPs) corresponding to subsequently remembered versus forgotten words was analyzed. These kind of studies revealed that successful memory encoding is characterized by an early process generated by the rhinal cortex within 300 ms following stimulus onset. This rhinal process precedes a hippocampal process, which starts about 200 ms later. Further investigation revealed that the rhinal process seems to be a correlate of semantic preprocessing which supports memory formation, whereas the hippocampal process appears to be a correlate of an exclusively mnemonic operation. These studies yielded only indirect evidence for an interaction of rhinal cortex and hippocampus. Direct evidence for a memory related cooperation between both structures, however, has been found in a study analyzing so called gamma activity, EEG oscillations of around 40 Hz. This investigation showed that successful as opposed to unsuccessful memory formation is accompanied by an initial enhancement of rhinal-hippocampal phase synchronization, which is followed by a later desynchronization. Present knowledge about the function of phase synchronized gamma activity suggests that this phase coupling and decoupling initiates and later terminates communication between the two MTL structures. Phase synchronized rhinal-hippocampal gamma activity may, moreover, accomplish Hebbian synaptic modifications and thus provide an initial step of declarative memory formation on the synaptic level.
Advanced Fatigue Damage Development in Graphite Epoxy Laminates.
1982-12-01
8217essary and identify by block number) Composite Materials Stiffness Changes Nondestructive Graphite/Epoxy Laminates Delamination Evaluation (NDE...30 3. Specimen in the Testing Machine with Extensometer Mounted ................................................. 32 4. Initial...for Micocrack Formation in [0,±45]. Laminat •s....115 43. Typical Stiffness Reduction Curve for a [0,90,±45]sLaminate
ERIC Educational Resources Information Center
Wammes, Birgitte; Breedveld, Boudewijn; Kremers, Stef; Brug, Johannes
2006-01-01
To help people prevent weight gain, the Netherlands Nutrition Centre initiated the "balance intervention", which promotes moderation of food intake and/or increased physical activity in response to occasions of overeating. The aim of this study was to determine whether intervention materials were appreciated, encouraged information…
Veena, Ravindran K; Ajith, Thekkuttuparambil A; Janardhanan, Kainoor K; Antonawich, Francis
2017-09-01
Chemopreventive agents which exhibit activities such as anti-inflammation, inhibition of carcinogen induced mutagenesis and scavenging of free radical might play a decisive role in the inhibition of chemical carcinogenesis either at the initiation or promotion stage. Many synthesized palladium (Pd) complexes tested experimentally for antitumor activity are found effective. Poly-MVA is a liquid blend preparation containing B complex vitamins, ruthenium with Pd complexed with alpha lipoic acid as the major ingredients. The antitumor effect of Poly-MVA was evaluated against 7,12-dimethylbenz[a] anthracene-initiated croton oil-promoted papilloma formation on mice skin. Skin tumor was initiated with a single application of 390 nmol of DMBA in 20 µl acetone. The effect of Poly-MVA against croton oil- induced inflammation and lipid peroxidation on the mice skin was also evaluated. Topical application of Poly-MVA (100 µl, twice weekly for 18 weeks) 30 minutes prior to each croton oil application, significantly decreased the tumor incidence (11%) and the average number of tumor per animals. Application of Poly-MVA (100 µl) before croton oil significantly (p < 0.05) protected the mouse skin from inflammation (36%) and lipid peroxidation (14%) when compared to the croton oil alone treated group. Experimental results indicate that Poly-MVA attenuate the tumor promoting effects of croton oil and the effect may probably be due to its anti-inflammatory and antioxidant activity.
Flight Deck Data Link Displays: An Evaluation of Textual and Graphical Implementations
NASA Technical Reports Server (NTRS)
McGann, Alison; Lozito, Sandy; Corker, Kevin; Ashford, Rose (Technical Monitor)
2001-01-01
In Experiment 1, 16 pilots participated in a part-task simulation study that evaluated pilot data link communication for short and long message types and for two textual formats. No differences were found between the two textual formats when evaluating data link transaction times and pilot performance on a secondary task. Pilots initiated flight changes more quickly with the T-Scan format, where location of clearance information roughly corresponded to the cockpit instrument layout. Longer messages were less problematic than two short messages sent in close succession as pilots required more verbal clarification for closely spaced messages. 24 pilots participated in a second experiment that evaluated pilot communication performance for textual data link, two implementations of graphical data link, and a combined graphical and textual information modality. The two modalities incorporating text resulted in significantly faster transaction times and better performance on the secondary task than the two graphical-only implementations. The interval between messages was also more systematically varied in Experiment 2, and a short interval between messages significantly increased the access time for the second message. This delay in access was long enough to increase significantly the total transaction time of the second message, and this effect was exaggerated for the graphical-only implementations. Time to view the message before acknowledgement and time to initiate flight changes were not affected by the interval manipulation, This suggests that pilots adopt a sequential message handling strategy, and presenting messages closely in succession may present operational problems in a data link Air Traffic Control (ATC) environment. The results of this study also indicate that the perceived importance of message content is currently a crucial element in pilot data link communication.
Beaulac, Julie; Edwards, Jeanette; Steele, Angus
2017-01-01
Aim To investigate the implementation and initial impact of the Physician Integrated Network (PIN) mental health indicators, which are specific to screening and managing follow-up for depression, in three primary care practices with Shared Mental Health Care in Manitoba. Manitoba Health undertook a primary care renewal initiative in 2006 called the PIN, which included the development of mental health indicators specific to screening and managing follow-up for depression. These indicators were implemented in three PIN group practice sites in Manitoba, which are also part of Shared Mental Health Care. The design was a non-experimental longitudinal design. A formative evaluation investigated the implementation and initial impact of the mental health indicators using mixed methods (document review, survey, and interview). Quantitative data was explored using descriptive and comparative statistics and a content and theme analysis of the qualitative interviews was conducted. Survey responses were received from 32 out of 36 physicians from the three sites. Interviews were conducted with 15 providers. Findings This evaluation illustrated providers' perceived attitudes, knowledge, skills, and behaviours related to recognizing and treating depression and expanded our understanding of primary care processes related to managing depression related to the implementation of a new initiative. Depression is viewed as an important problem in primary care practice that is time consuming to diagnose, manage and treat and requires further investigation. Implementation of the PIN mental health indicators was variable across sites and providers. There was an increase in use of the indicators across time and a general sentiment that benefits of screening outweigh the costs; however, the benefit of screening for depression remains unclear. Consistent with current guidelines, a question the findings of this evaluation suggests is whether there are more effective ways of having an impact on depression within primary care than screening.
Ten Eyck, Raymond P; Tews, Matthew; Ballester, John M; Hamilton, Glenn C
2010-06-01
To determine the impact of simulation-based instruction on student performance in the role of emergency department resuscitation team leader. A randomized, single-blinded, controlled study using an intention to treat analysis. Eighty-three fourth-year medical students enrolled in an emergency medicine clerkship were randomly allocated to two groups differing only by instructional format. Each student individually completed an initial simulation case, followed by a standardized curriculum of eight cases in either group simulation or case-based group discussion format before a second individual simulation case. A remote coinvestigator measured eight objective performance end points using digital recordings of all individual simulation cases. McNemar chi2, Pearson correlation, repeated measures multivariate analysis of variance, and follow-up analysis of variance were used for statistical evaluation. Sixty-eight students (82%) completed both initial and follow-up individual simulations. Eight students were lost from the simulation group and seven from the discussion group. The mean postintervention case performance was significantly better for the students allocated to simulation instruction compared with the group discussion students for four outcomes including a decrease in mean time to (1) order an intravenous line; (2) initiate cardiac monitoring; (3) order initial laboratory tests; and (4) initiate blood pressure monitoring. Paired comparisons of each student's initial and follow-up simulations demonstrated significant improvement in the same four areas, in mean time to order an abdominal radiograph and in obtaining an allergy history. A single simulation-based teaching session significantly improved student performance as a team leader. Additional simulation sessions provided further improvement compared with instruction provided in case-based group discussion format.
Feline crystalluria. Detection and interpretation.
Osborne, C A; Lulich, J P; Ulrich, L K; Bird, K A
1996-03-01
Crystalluria results from oversaturation of urine with crystallogenic substances. However, oversaturation may occur as a result of in vivo and in vitro events. Therefore, care must be used not to overinterpret the significance of crystalluria. Evaluation of urine crystals may aid in (1) detection of disorders predisposing cats to urolith or matrix-crystalline urethral plug formation; (2) estimation of the mineral composition of uroliths or urethral plugs; and (3) evaluation of the effectiveness of medical protocols initiated to dissolve or prevent urolithiasis.
Papalexopoulou, Konstantina; Chalkias, Athanasios; Dontas, Ioannis; Pliatsika, Paraskevi; Giannakakos, Charalampos; Papapanagiotou, Panagiotis; Aggelina, Afroditi; Moumouris, Theodoros; Papadopoulos, Georgios; Xanthos, Theodoros
2014-01-01
To examine whether education and age affect skill acquisition and retention in lay rescuers after a European Resuscitation Council (ERC) CPR/AED course. Because of the importance of bystander CPR/AED skills in the setting of cardiac arrest, acquisition and retention of resuscitation skills has gained a great amount of interest. The ERC CPR/AED course format for written and practical evaluation was used. Eighty lay people were trained and evaluated at the end of the course, as well as at one, three, and six months. Retention of CPR/AED skills improved over time, recording the lowest practical scores at one month after initial training and the lowest written scores at initial training. In practical evaluation scores, when examined longitudinally, age presented a significant adverse effect and higher background education presented a non-significant positive effect. Moreover, regarding written evaluation scores, when examined longitudinally, education presented a significant positive effect while age did not significantly correlate with written scores. Education and age affected retention of CPR/AED skills in lay rescuers. Also, our results suggest that the ERC CPR/AED course format may be poorly designed to discriminate between participants with different levels of practical and written resuscitation skills and merit a thorough investigation in future studies. Copyright © 2014 Elsevier Inc. All rights reserved.
Optimization of Game Formats in U-10 Soccer Using Logistic Regression Analysis
Amatria, Mario; Arana, Javier; Anguera, M. Teresa; Garzón, Belén
2016-01-01
Abstract Small-sided games provide young soccer players with better opportunities to develop their skills and progress as individual and team players. There is, however, little evidence on the effectiveness of different game formats in different age groups, and furthermore, these formats can vary between and even within countries. The Royal Spanish Soccer Association replaced the traditional grassroots 7-a-side format (F-7) with the 8-a-side format (F-8) in the 2011-12 season and the country’s regional federations gradually followed suit. The aim of this observational methodology study was to investigate which of these formats best suited the learning needs of U-10 players transitioning from 5-aside futsal. We built a multiple logistic regression model to predict the success of offensive moves depending on the game format and the area of the pitch in which the move was initiated. Success was defined as a shot at the goal. We also built two simple logistic regression models to evaluate how the game format influenced the acquisition of technicaltactical skills. It was found that the probability of a shot at the goal was higher in F-7 than in F-8 for moves initiated in the Creation Sector-Own Half (0.08 vs 0.07) and the Creation Sector-Opponent's Half (0.18 vs 0.16). The probability was the same (0.04) in the Safety Sector. Children also had more opportunities to control the ball and pass or take a shot in the F-7 format (0.24 vs 0.20), and these were also more likely to be successful in this format (0.28 vs 0.19). PMID:28031768
Farrell, Richard J; Alsahli, Mazen; Jeen, Yoon-Tae; Falchuk, Kenneth R; Peppercorn, Mark A; Michetti, Pierre
2003-04-01
We assessed the relationship between antibodies to infliximab (ATI) and the loss of response postinfliximab, infusion reactions and, in a randomized trial, investigated whether intravenous hydrocortisone premedication can reduce ATI. Initially, we prospectively evaluated clinical response, adverse events, and ATI levels in 53 consecutive patients with Crohn's disease who received 199 infliximab (5 mg/kg) infusions. Subsequently, 80 patients with Crohn's disease were randomized to intravenous hydrocortisone 200 mg or placebo immediately before their first and subsequent infliximab infusions. The primary endpoint was reduction in median ATI levels at week 16. Analysis was by intention to treat. Nineteen of our initial 53 patients (36%) developed ATI, including all 7 patients with serious infusion reactions (median ATI level, 19.6 microg/mL). Eleven of 15 patients (73%) who lost their initial response were ATI positive compared with none of 21 continuous responders, (8.9 vs. 0.7 microg/mL, P < 0.0001). Administering a second infusion within 8 weeks of the first (OR, 0.13; 95% CI, 0.03-0.5; P = 0.0007) or concurrent immunosuppressants (OR, 0.19; 95% CI, 0.04-1.03; P = 0.007) significantly reduced ATI formation. In the placebo-controlled trial, ATI levels were lower at week 16 among hydrocortisone-treated patients (1.6 vs. 3.4 microg/mL, P = 0.02), and 26% of hydrocortisone-treated patients developed ATI compared with 42% of placebo-treated patients, P = 0.06. Loss of initial response and infusion reactions post-infliximab is strongly related to ATI formation and level. Administering a second infusion within 8 weeks of the first and concurrent immunosuppressant therapy significantly reduce ATI formation. Intravenous hydrocortisone premedication significantly reduces ATI levels but does not eliminate ATI formation or infusion reactions.
NASA Astrophysics Data System (ADS)
Shibata, Yukie; Yamashita, Yoshihisa; Tsuru, Kanji; Ishihara, Kazuhiko; Fukazawa, Kyoko; Ishikawa, Kunio
2016-12-01
The regulation of biofilm formation on dental materials such as denture bases is key to oral health. Recently, a biocompatible phospholipid polymer, poly(2-methacryloyloxyethyl phosphorylcholine-co-n-butyl methacrylate) (PMB) coating, was reported to inhibit sucrose-dependent biofilm formation by Streptococcus mutans, a cariogenic bacterium, on the surface of poly(methyl methacrylate) (PMMA) denture bases. However, S. mutans is a minor component of the oral microbiome and does not play an important role in biofilm formation in the absence of sucrose. Other, more predominant oral streptococci must play an indispensable role in sucrose-independent biofilm formation. In the present study, the effect of PMB coating on PMMA was evaluated using various oral streptococci that are known to be initial colonizers during biofilm formation on tooth surfaces. PMB coating on PMMA drastically reduced sucrose-dependent tight biofilm formation by two cariogenic bacteria (S. mutans and Streptococcus sobrinus), among seven tested oral streptococci, as described previously [N. Takahashi, F. Iwasa, Y. Inoue, H. Morisaki, K. Ishihara, K. Baba, J. Prosthet. Dent. 112 (2014) 194-203]. Streptococci other than S. mutans and S. sobrinus did not exhibit tight biofilm formation even in the presence of sucrose. On the other hand, all seven species of oral streptococci exhibited distinctly reduced glucose-dependent soft biofilm retention on PMB-coated PMMA. We conclude that PMB coating on PMMA surfaces inhibits biofilm attachment by initial colonizer oral streptococci, even in the absence of sucrose, indicating that PMB coating may help maintain clean conditions on PMMA surfaces in the oral cavity.
Barbosa, Judite N; Amaral, Isabel F; Aguas, Artur P; Barbosa, Mário A
2010-04-01
The effect of the degree of acetylation (DA) of 3D chitosan (Ch) scaffolds on the inflammatory reaction was investigated. Chitosan porous scaffolds with DAs of 4 and 15% were implanted using a subcutaneous air-pouch model of inflammation. The initial acute inflammatory response was evaluated 24 and 48 h after implantation. To characterize the initial response, the recruitment and adhesion of inflammatory cells to the implant site was studied. The fibrous capsule formation and the infiltration of inflammatory cells within the scaffolds were evaluated for longer implantation times (2 and 4 weeks). Chitosan with DA 15% attracted the highest number of leukocytes to the implant site. High numbers of adherent inflammatory cells were also observed in this material. For longer implantation periods Ch scaffolds with a DA of 15% induced the formation of a thick fibrous capsule and a high infiltration of inflammatory cells within the scaffold. Our results indicate that the biological response to implanted Ch scaffolds was influenced by the DA. Chitosan with a DA of 15% induce a more intense inflammatory response when compared with DA 4% Ch. Because inflammation and healing are interrelated, this result may provide clues for the relative importance of acetyl and amine functional groups in tissue repair and regeneration.
ERIC Educational Resources Information Center
Perry, Rebecca R.; Finkelstein, Neal D.; Seago, Nanette; Heredia, Alberto; Sobolew-Shubin, Sandy; Carroll, Cathy
2015-01-01
Math in Common® (MiC) is a five-year initiative that supports a formal network of 10 California school districts as they implement the Common Core State Standards in Mathematics (CCSS-M) across grades K-8. In spring 2015, WestEd administered surveys to understand the perspectives on Common Core State Standards-Mathematics (CCSS-M) implementation…
Updating histological data on crown initiation and crown completion ages in southern Africans.
Reid, Donald J; Guatelli-Steinberg, Debbie
2017-04-01
To update histological data on crown initiation and completion ages in southern Africans. To evaluate implications of these data for studies that: (a) rely on these data to time linear enamel hypoplasias (LEHs), or, (b) use these data for comparison to fossil hominins. Initiation ages were calculated on 67 histological sections from southern Africans, with sample sizes ranging from one to 11 per tooth type. Crown completion ages for southern Africans were calculated in two ways. First, actual derived initiation ages were added to crown formation times for each histological section to obtain direct information on the crown completion ages of individuals. Second, average initiation ages from this study were added to average crown formation times of southern Africans from the Reid and coworkers previous studies that were based on larger samples. For earlier-initiating tooth types (all anterior teeth and first molars), there is little difference in ages of initiation and crown completion between this and previous studies. Differences increase as a function of initiation age, such that the greatest differences between this and previous studies for both initiation and crown completion ages are for the second and third molars. This study documents variation in initiation ages, particularly for later-initiating tooth types. It upholds the use of previously published histological aging charts for LEHs on anterior teeth. However, this study finds that ages of crown initiation and completion in second and third molars for this southern African sample are earlier than previously estimated. These earlier ages reduce differences between modern humans and fossil hominins for these developmental events in second and third molars. © 2017 Wiley Periodicals, Inc.
Local injection of methylprednisolonacetat to prevent seroma formation after mastectomy.
Axelsson, Christen Kirk; Quamme, Gro Maria; Lanng, Charlotte; Szecsi, Pal Bela; Mortensen, Minea Brusgaard; Wegeberg, Birgitte; Arpi, Magnus; Lingskov, Marianne; Puglich, Mette Stub; Okholm, Mette
2012-09-01
This study served the following three purposes: To evaluate the prophylactic effect against seroma of a single dose of steroid in the mastectomy cavity, to evaluate the thesis that there is a connection between subclinical bacterial colonization and seroma formation and to evaluate if a simple urine stix test can detect postmastectomy infection. This was a double-blinded and randomized study of injection of methylprednisolonacetate versus saline in the mastectomy cavity at the time of drain removal. A total of 160 females were enrolled after mastectomy. The study parameters were as follows: seroma volume, number of seroma punctures, frequency of clinical infections, degree and type of subclinical colonization, complications and evaluation of the microbiological results of the stix test with automatically read glucose, ketones, blood, pH, protein, nitrite and leucocytes. The degree of inflammation was monitored by measurement of 15 cytokines in each sample of seroma fluid. The study was initiated in August 2010 and is expected to run for three years. Some reports have concluded that seroma formation forms part of postsurgical inflammation. Steroids are effective against inflammation and accumulation of fluid at the surgical site after several types of surgery and have also proved valuable in the treatment of seroma formation. In the present study, the prophylactic effect of steroids on seroma formation is investigated. As the incidence of postmastectomy seroma formation is 80%, there is a need for improvement in the prophylaxis and treatment of this condition. not relevant. Medicines Agency The EudraCT number 2009-016650-40 has been issued for your Sponsor's Protocol Code Number 23837. Data protection agency J.no. F.750.75-2. The study is perfomed in collaboration with the GCP Unit, capital Region, Bispebjerg Hospital under the EudraCT number: 2009-016650-40.
When to Adapt Materials and When to Initiate Fresh Instructional Development.
ERIC Educational Resources Information Center
Rojas, Alicia M.
A study was conducted to examine the procedures and requirements of a formative evaluation when it is carried out for instructional materials that have been designed for a U.S. target audience, but which also have potential use by a population of another country, e.g., Brazil. The study concentrated on determining whether different formative…
2014-01-01
Background The traditional lecture is used by many residency programs to fulfill the mandate for regular didactic sessions, despite limited evidence to demonstrate its effectiveness. Active teaching strategies have shown promise in improving medical knowledge but have been challenging to implement within the constraints of residency training. We developed and evaluated an innovative structured format for interactive teaching within the residency noon conference. Methods We developed an ACTIVE teaching format structured around the following steps: assemble (A) into groups, convey (C) learning objectives, teach (T) background information, inquire (I) through cases and questions, verify (V) understanding, and explain (E) answer choices and educate on the learning points. We conducted a prospective, controlled study of the ACTIVE teaching format versus the standard lecture format, comparing resident satisfaction, immediate knowledge achievement and long-term knowledge retention. We qualitatively assessed participating faculty members’ perspectives on the faculty development efforts and the feasibility of teaching using the ACTIVE format. Results Sixty-nine internal medicine residents participated in the study. Overall, there was an improvement in perceived engagement using the ACTIVE teaching format (4.78 vs. 3.80, P < 0.01), with no increase in stress or decrement in break time. There was an improvement in initial knowledge achievement with the ACTIVE teaching format (overall absolute score increase of 11%, P = 0.04) and a trend toward improvement in long-term knowledge retention. Faculty members felt adequately prepared to use the ACTIVE teaching format, and enjoyed teaching with the ACTIVE teaching format more than the standard lecture. Conclusions A structured ACTIVE teaching format improved resident engagement and initial knowledge, and required minimal resources. The ACTIVE teaching format offers an exciting alternative to the standard lecture for resident noon conference and is easy to implement. PMID:24985781
Solid-gas phase equilibria and thermodynamic properties of cadmium selenide.
NASA Technical Reports Server (NTRS)
Sigai, A. G.; Wiedemeier, H.
1972-01-01
Accurate vapor pressures are determined through direct weight loss measurements using the Knudsen effusion technique. The experimental data are evaluated by establishing the mode of vaporization and determining the heat capacity of cadmium selenide at elevated temperatures. Additional information is obtained through a second- and third-law evaluation of data, namely, the heat of formation and the absolute entropy of cadmium selenide. A preferential loss of selenium during the initial heating of CdSe is observed, which leads to a deviation in stoichiometry.
Follow-On Development of Structured Training for the Close Combat Tactical Trainer.
1998-07-01
and Evaluation ( IOT &E) scheduled for the second quarter of FY 1998. Though the STRUCCTT Project provided a variety of exercises for the initial...References 73 APPENDIX A. ACRONYMS A-l B. FORMATIVE EVALUATION PROJECT LOG B-l C. TASK CHARTS C-l D. TASK FORCE SCHEDULE D-l E. SURVEY...phases of all three missions. The proponent selected tables to be developed assuring that most capabilities of the CCTT were used during the IOT &E
Yang, Zhenyu; Gonzalez, Christina M; Purkait, Tapas K; Iqbal, Muhammad; Meldrum, Al; Veinot, Jonathan G C
2015-09-29
Hydrosilylation is among the most common methods used for modifying silicon surface chemistry. It provides a wide range of surface functionalities and effective passivation of surface sites. Herein, we report a systematic study of radical initiated hydrosilylation of silicon nanocrystal (SiNC) surfaces using two common radical initiators (i.e., 2,2'-azobis(2-methylpropionitrile) and benzoyl peroxide). Compared to other widely applied hydrosilylation methods (e.g., thermal, photochemical, and catalytic), the radical initiator based approach is particle size independent, requires comparatively low reaction temperatures, and yields monolayer surface passivation after short reaction times. The effects of differing functional groups (i.e., alkene, alkyne, carboxylic acid, and ester) on the radical initiated hydrosilylation are also explored. The results indicate functionalization occurs and results in the formation of monolayer passivated surfaces.
Cook, Troy A.
2013-01-01
Estimated ultimate recoveries (EURs) are a key component in determining productivity of wells in continuous-type oil and gas reservoirs. EURs form the foundation of a well-performance-based assessment methodology initially developed by the U.S. Geological Survey (USGS; Schmoker, 1999). This methodology was formally reviewed by the American Association of Petroleum Geologists Committee on Resource Evaluation (Curtis and others, 2001). The EUR estimation methodology described in this paper was used in the 2013 USGS assessment of continuous oil resources in the Bakken and Three Forks Formations and incorporates uncertainties that would not normally be included in a basic decline-curve calculation. These uncertainties relate to (1) the mean time before failure of the entire well-production system (excluding economics), (2) the uncertainty of when (and if) a stable hyperbolic-decline profile is revealed in the production data, (3) the particular formation involved, (4) relations between initial production rates and a stable hyperbolic-decline profile, and (5) the final behavior of the decline extrapolation as production becomes more dependent on matrix storage.
Basler, J.A.
1983-01-01
Requirements for testing hydrologic test wells at the proposed Waste Isolation Pilot Plant near Carlsbad, New Mexico, necessitated the use of inflatable formation packers and pressure transducers. Observations during drilling and initial development indicated small formation yields which would require considerable test times by conventional open-casing methods. A pressure-monitoring system was assembled for performance evaluation utilizing commercially available components. Formation pressures were monitored with a down-hole strain-gage transducer. An inflatable packer equipped with a 1/4-inch-diameter steel tube extending through the inflation element permitted sensing formation pressures in isolated test zones. Surface components of the monitoring system provided AC transducer excitation, signal conditioning for recording directly in engineering units, and both analog and digital recording. Continuous surface monitoring of formation pressures provided a means of determining test status and projecting completion times during any phase of testing. Maximum portability was afforded by battery operation with all surface components mounted in a small self-contained trailer. (USGS)
Apetrei, Roxana-Mihaela; Carac, Geta; Bahrim, Gabriela; Ramanaviciene, Almira; Ramanavicius, Arunas
2018-06-01
The enhancement of bioelectrochemical properties of microorganism by in situ formation of conducting polymer within the cell structures (e.g. cell wall) was performed. The synthesis of polypyrrole (Ppy) within fungi (Aspergillus niger) cells was achieved. Two different Aspergillus niger strains were selected due to their ability to produce glucose oxidase, which initiated the Ppy formation through products of enzymatic reaction. The evolution of Ppy structural features was investigated by absorption spectroscopy, cyclic voltammetry and Fourier transform infrared spectroscopy. Copyright © 2018 Elsevier B.V. All rights reserved.
Orchard, Sandra; Hermjakob, Henning
2008-03-01
The amount of data currently being generated by proteomics laboratories around the world is increasing exponentially, making it ever more critical that scientists are able to exchange, compare and retrieve datasets when re-evaluation of their original conclusions becomes important. Only a fraction of this data is published in the literature and important information is being lost every day as data formats become obsolete. The Human Proteome Organisation Proteomics Standards Initiative (HUPO-PSI) was tasked with the creation of data standards and interchange formats to allow both the exchange and storage of such data irrespective of the hardware and software from which it was generated. This article will provide an update on the work of this group, the creation and implementation of these standards and the standards-compliant data repositories being established as result of their efforts.
Polymerization Behavior and Polymer Properties of Eosin-Mediated Surface Modification Reactions.
Avens, Heather J; Randle, Thomas James; Bowman, Christopher N
2008-10-17
Surface modification by surface-mediated polymerization necessitates control of the grafted polymer film thicknesses to achieve the desired property changes. Here, a microarray format is used to assess a range of reaction conditions and formulations rapidly in regards to the film thicknesses achieved and the polymerization behavior. Monomer formulations initiated by eosin conjugates with varying concentrations of poly(ethylene glycol) diacrylate (PEGDA), N-methyldiethanolamine (MDEA), and 1-vinyl-2-pyrrolidone (VP) were evaluated. Acrylamide with MDEA or ascorbic acid as a coinitiator was also investigated. The best formulation was found to be 40 wt% acrylamide with MDEA which yielded four to eight fold thicker films (maximum polymer thickness increased from 180 nm to 1420 nm) and generated visible films from 5-fold lower eosin surface densities (2.8 vs. 14 eosins/µm(2)) compared to a corresponding PEGDA formulation. Using a microarray format to assess multiple initiator surface densities enabled facile identification of a monomer formulation that yields the desired polymer properties and polymerization behavior across the requisite range of initiator surface densities.
Polymerization Behavior and Polymer Properties of Eosin-Mediated Surface Modification Reactions
Avens, Heather J.; Randle, Thomas James; Bowman, Christopher N.
2008-01-01
Surface modification by surface-mediated polymerization necessitates control of the grafted polymer film thicknesses to achieve the desired property changes. Here, a microarray format is used to assess a range of reaction conditions and formulations rapidly in regards to the film thicknesses achieved and the polymerization behavior. Monomer formulations initiated by eosin conjugates with varying concentrations of poly(ethylene glycol) diacrylate (PEGDA), N-methyldiethanolamine (MDEA), and 1-vinyl-2-pyrrolidone (VP) were evaluated. Acrylamide with MDEA or ascorbic acid as a coinitiator was also investigated. The best formulation was found to be 40 wt% acrylamide with MDEA which yielded four to eight fold thicker films (maximum polymer thickness increased from 180 nm to 1420 nm) and generated visible films from 5-fold lower eosin surface densities (2.8 vs. 14 eosins/µm2) compared to a corresponding PEGDA formulation. Using a microarray format to assess multiple initiator surface densities enabled facile identification of a monomer formulation that yields the desired polymer properties and polymerization behavior across the requisite range of initiator surface densities. PMID:19838291
Zhou, S; Wang, Z; Tang, J; Li, W; Huang, J; Xu, W; Luo, F; Xu, M; Wang, J; Wen, X; Chen, L; Chen, H; Su, N; Shen, Y; Du, X; Xie, Y; Chen, L
2016-12-01
The aim of the present study is to investigate the effects of exogenous fibroblast growth factor (FGF)9 on the progression of post-traumatic osteoarthritis (OA). The expression of FGF9 in articular cartilage with OA is detected by immunohistochemistry (IHC). The effects of intra-articular exogenous FGF9 injection on post-traumatic OA induced by the destabilization of the medial meniscus (DMM) surgery are evaluated. Cartilage changes and osteophyte formation in knee joints are investigated by histological analysis. Changes in subchondral bone are evaluated by microcomputed tomography (micro-CT). The effect of exogenous FGF9 on an interleukin-1β (IL-1β)-induced ex vivo OA model of human articular cartilage tissues is also evaluated. FGF9 expression was down-regulated in articular chondrocytes of OA but ectopically induced at sites of osteophyte formation. Intra-articular injection of exogenous FGF9 attenuated articular cartilage degradation in mice after DMM surgery. Exogenous FGF9 suppressed collagen X and MMP13 expressions in OA cartilage, while promoted collagen II expression. Similar results were observed in IL-1β-induced ex vivo OA model. Intra-articular injection of FGF9 had no significant effect on the subchondral bone of knee joints after DMM surgery, but aggravated osteophyte formation. The expressions of SOX9 and collagen II, and cell proliferation were up-regulated at sites of initial osteophyte formation in mice with exogenous FGF9 treatment. Intra-articular injection of exogenous FGF9 delays articular cartilage degradation in post-traumatic OA, while aggravates osteophyte formation. Copyright © 2016. Published by Elsevier Ltd.
ERIC Educational Resources Information Center
Ezumah, Bellarmine Anthonia
2010-01-01
Copious educational technology projects have been implemented in several low-income communities by multilateral institutions, individuals, and governmental agencies. Statistics show that the majority of these initiatives fail to accomplish their objectives, thereby wasting colossal amounts of money, talent, and resources. Scholars aver that poor…
Time-reversed, flow-reversed ballistics simulations
DOE Office of Scientific and Technical Information (OSTI.GOV)
Zernow, L.; Chapyak, E. J.; Scheffler, D. R.
2001-01-01
Two-dimensional simulations of planar sheet jet formation are studied to examine the hydrodynamic issues involved when simulations are carried out in the inverse direction, that is, with reversed time and flow. Both a realistic copper equation of state and a shockless equation of state were used. These studies are an initial step in evaluating this technique as a ballistics design tool.
ERIC Educational Resources Information Center
Natker, Elana; Baker, Susan S.; Auld, Garry; McGirr, Kathryn; Sutherland, Barbara; Cason, Katherine L.
2015-01-01
The project reported here served to assess a curriculum for EFNEP to ensure theory compliance and content validity. Adherence to Adult Learning Theory and Social Cognitive Theory tenets was determined. A curriculum assessment tool was developed and used by five reviewers to assess initial and revised versions of the curriculum. T-tests for…
Discovery Systems for Manufacturing
1994-01-01
Rev. Letters, 68, Number 10, pp 1500-1503, 1992. Karp, Peter D., Hypothesis Formation and Qualitative Reasoning in Molecular Biology, Ph.D. Thesis ...1-4 2.5.1.2 Evaluating Attributes ........................ 2-17 1.21.4 The Simulated Laboratory ..............1-4 2.5.2 Nearest...4-11vs. Conventional Ae Cs R ............... 2-6 4.33 Initialize Simulator ......... ........... 4-112.4.12.1 Similarities
Striving for Discussion: An Analysis of a Teacher Educator's Comments in Whole-Class Conversation
ERIC Educational Resources Information Center
Reynolds, Todd
2016-01-01
During my English Language Arts methods class, I noticed that my discussion patterns were teacher-focused and in an Initiation-Response-Evaluation format. Because I wanted to model dialogic methods of whole-class discussions for my preservice teachers, I recoiled from this finding and began a self-study using an action research method to examine…
ERIC Educational Resources Information Center
McKibben, Stephen
2013-01-01
In this analysis of practice, I conduct a combination formative and summative program evaluation of an initiative introduced to serve gifted learners at The Ocean School (TOS), an independent, Pre-K-grade 8 day school located in a rural area of the West Coast. Using the best practices as articulated by the National Association of Gifted Children…
Online Learning Community Development with Teachers as a Means of Enhancing Initial Teacher Training
ERIC Educational Resources Information Center
Hramiak, Alison
2010-01-01
A purpose-built blend of teaching and learning activities was used with trainee teachers on a Postgraduate Certificate in Education (PGCE) course, and subsequently evaluated in a cyclical action research study, over a period of two years. The purpose of the blend was to engender the formation of a learning community, by giving them access to each…
ERIC Educational Resources Information Center
Willis, Mike; Kennedy, Rowan
2004-01-01
This research identifies a range of issues and factors which impact on the formation of initial expectations developed by local university students wishing to study for a foreign degree program in Hong Kong. Key factors were foreign university Internet sites, exhibitions, agents and associations, brochures and friends. This is one of the first…
ERIC Educational Resources Information Center
Boh, Larry E.; And Others
1987-01-01
A project to (1) develop and apply a microcomputer simulation program to enhance clinical medication problem solving in preclerkship and clerkship students and (2) perform an initial formative evaluation of the simulation is described. A systematic instructional design approach was used in applying the simulation to the disease state of rheumatoid…
Yang, Zixuan; Kan, Bo; Li, Jinxu; Qiao, Lijie; Volinsky, Alex A; Su, Yanjing
2017-11-14
Hydrostatic pressure effects on pitting initiation and propagation in X70 steel are investigated by evaluating metastable pitting probability using electrochemical methods and immersion corrosion tests in containing chlorine ion solution. Potentiodynamic tests indicated that hydrostatic pressure can decrease the breakdown potential and lead to a reduced transpassivity region. Metastable test results revealed that hydrostatic pressure can increase metastable pitting formation frequency and promote stabilization of metastable pitting growth. Electrochemical impedance spectroscopy (EIS) results indicate that Hydrostatic pressure decreases the charge transfer resistance and increases the dissolution rate within the cavities. Corrosion test results also indicated that pitting initiation and propagation are accelerated by hydrostatic pressure. Result validity was verified by evaluating metastable pitting to predict pitting corrosion resistance.
Yang, Zixuan; Kan, Bo; Li, Jinxu; Su, Yanjing; Qiao, Lijie; Volinsky, Alex A.
2017-01-01
Hydrostatic pressure effects on pitting initiation and propagation in X70 steel are investigated by evaluating metastable pitting probability using electrochemical methods and immersion corrosion tests in containing chlorine ion solution. Potentiodynamic tests indicated that hydrostatic pressure can decrease the breakdown potential and lead to a reduced transpassivity region. Metastable test results revealed that hydrostatic pressure can increase metastable pitting formation frequency and promote stabilization of metastable pitting growth. Electrochemical impedance spectroscopy (EIS) results indicate that Hydrostatic pressure decreases the charge transfer resistance and increases the dissolution rate within the cavities. Corrosion test results also indicated that pitting initiation and propagation are accelerated by hydrostatic pressure. Result validity was verified by evaluating metastable pitting to predict pitting corrosion resistance. PMID:29135912
Solar TiO2-assisted photocatalytic degradation of IGCC power station effluents using a Fresnel lens.
Monteagudo, J M; Durán, A; Guerra, J; García-Peña, F; Coca, P
2008-03-01
The heterogeneous TiO2 assisted photocatalytic degradation of wastewater from a thermoelectric power station under concentrated solar light irradiation using a Fresnel lens has been studied. The efficiency of photocatalytic degradation was determined from the analysis of cyanide and formate removal. Firstly, the influence of the initial concentration of H2O2 and TiO2 on the degradation kinetics of cyanides and formates was studied based on a factorial experimental design. Experimental kinetic constants were fitted using neural networks. Results showed that the photocatalytic process was effective for cyanides destruction (mainly following a molecular mechanism), whereas most of formates (degraded mainly via a radical path) remained unaffected. Finally, to improve formates degradation, the effect of lowering pH on their degradation rate was evaluated after complete cyanide destruction. The photooxidation efficiency of formates reaches a maximum at pH around 5-6. Above pH 6, formate anion is subjected to electrostatic repulsion with the negative surface of TiO2. At pH<4.5, formate adsorption and photon absorption are reduced due to some catalyst agglomeration.
A case study examining classroom instructional practices at a U.S. dental school.
Behar-Horenstein, Linda S; Mitchell, Gail S; Dolan, Teresa A
2005-06-01
A case study is used to illustrate how an evaluation strategy was used to assess classroom instructional practices following a multiyear institutional curriculum revision process. From January through April of 2003, twelve faculty in medicine and three faculty in dentistry who taught in the first- and second-year basic science courses within the dental curriculum participated in a qualitative study. The purpose was to use a formative evaluation process to assess the impact of the curriculum revision at the level of classroom instruction. The observations revealed that seventeen of the twenty classes observed were teacher-centered, passive, and lacked observable effort to help students understand the relationship of the lecture content to the oral health problems. Findings illustrate the importance of using formative evaluation as a mechanism to assess change efforts and how evidence-based study can be used to support initiatives directed toward assessing active student learning and problem solving. Raising faculty awareness about the importance of acquiring evidence-based educational skills, aligning instruction with course goals and objectives, formatively assessing teaching, and providing learning experiences that will actually be used in practice are essential to ensuring that active learning and critical thinking are demonstrated in the curriculum.
ERIC Educational Resources Information Center
Louie, Josephine; Sanchez, Maria Teresa; North, Charlotte; Cazabon, Mary; Melo, Daniel; Kagle, Melissa
2011-01-01
This study examines two state-supported formative assessment initiatives that promote a consensus definition of formative assessment endorsed by the Council of Chief State School Officers. It describes the primary components of the two initiatives and the strategies that state, district, and school leaders report using to support implementation of…
ERIC Educational Resources Information Center
Louie, Josephine; Sanchez, Maria Teresa; North, Charlotte; Cazabon, Mary; Melo, Daniel; Kagle, Melissa
2011-01-01
This study examines two state-supported formative assessment initiatives that promote a consensus definition of formative assessment endorsed by the Council of Chief State School Officers. It describes the primary components of the two initiatives and the strategies that state, district, and school leaders report using to support implementation of…
Modulation format identification aided hitless flexible coherent transceiver.
Xiang, Meng; Zhuge, Qunbi; Qiu, Meng; Zhou, Xingyu; Zhang, Fangyuan; Tang, Ming; Liu, Deming; Fu, Songnian; Plant, David V
2016-07-11
We propose a hitless flexible coherent transceiver enabled by a novel modulation format identification (MFI) scheme for dynamic agile optical networks. The modulation format transparent digital signal processing (DSP) is realized by a block-wise decision-directed least-mean-square (DD-LMS) equalizer for channel tracking, and a pilot symbol aided superscalar phase locked loop (PLL) for carrier phase estimation (CPE). For the MFI, the modulation format information is encoded onto the pilot symbols initially used for CPE. Therefore, the proposed MFI method does not require extra overhead. Moreover, it can identify arbitrary modulation formats including multi-dimensional formats, and it enables tracking of the format change for short data blocks. The performance of the proposed hitless flexible coherent transceiver is successfully evaluated with five modulation formats including QPSK, 16QAM, 64QAM, Hybrid QPSK/8QAM and set-partitioning (SP)-512-QAM. We show that the proposed MFI method induces a negligible performance penalty. Moreover, we experimentally demonstrate that such a hitless transceiver can adapt to fast block-by-block modulation format switching. Finally, the performance improvement of the proposed MFI method is experimentally verified with respect to other commonly used MFI methods.
Predicting episodic memory formation for movie events
Tang, Hanlin; Singer, Jed; Ison, Matias J.; Pivazyan, Gnel; Romaine, Melissa; Frias, Rosa; Meller, Elizabeth; Boulin, Adrianna; Carroll, James; Perron, Victoria; Dowcett, Sarah; Arellano, Marlise; Kreiman, Gabriel
2016-01-01
Episodic memories are long lasting and full of detail, yet imperfect and malleable. We quantitatively evaluated recollection of short audiovisual segments from movies as a proxy to real-life memory formation in 161 subjects at 15 minutes up to a year after encoding. Memories were reproducible within and across individuals, showed the typical decay with time elapsed between encoding and testing, were fallible yet accurate, and were insensitive to low-level stimulus manipulations but sensitive to high-level stimulus properties. Remarkably, memorability was also high for single movie frames, even one year post-encoding. To evaluate what determines the efficacy of long-term memory formation, we developed an extensive set of content annotations that included actions, emotional valence, visual cues and auditory cues. These annotations enabled us to document the content properties that showed a stronger correlation with recognition memory and to build a machine-learning computational model that accounted for episodic memory formation in single events for group averages and individual subjects with an accuracy of up to 80%. These results provide initial steps towards the development of a quantitative computational theory capable of explaining the subjective filtering steps that lead to how humans learn and consolidate memories. PMID:27686330
Predicting episodic memory formation for movie events.
Tang, Hanlin; Singer, Jed; Ison, Matias J; Pivazyan, Gnel; Romaine, Melissa; Frias, Rosa; Meller, Elizabeth; Boulin, Adrianna; Carroll, James; Perron, Victoria; Dowcett, Sarah; Arellano, Marlise; Kreiman, Gabriel
2016-09-30
Episodic memories are long lasting and full of detail, yet imperfect and malleable. We quantitatively evaluated recollection of short audiovisual segments from movies as a proxy to real-life memory formation in 161 subjects at 15 minutes up to a year after encoding. Memories were reproducible within and across individuals, showed the typical decay with time elapsed between encoding and testing, were fallible yet accurate, and were insensitive to low-level stimulus manipulations but sensitive to high-level stimulus properties. Remarkably, memorability was also high for single movie frames, even one year post-encoding. To evaluate what determines the efficacy of long-term memory formation, we developed an extensive set of content annotations that included actions, emotional valence, visual cues and auditory cues. These annotations enabled us to document the content properties that showed a stronger correlation with recognition memory and to build a machine-learning computational model that accounted for episodic memory formation in single events for group averages and individual subjects with an accuracy of up to 80%. These results provide initial steps towards the development of a quantitative computational theory capable of explaining the subjective filtering steps that lead to how humans learn and consolidate memories.
Impact of planet-planet scattering on the formation and survival of debris discs
NASA Astrophysics Data System (ADS)
Marzari, F.
2014-10-01
Planet-planet scattering is a major dynamical mechanism able to significantly alter the architecture of a planetary system. In addition to that, it may also affect the formation and retention of a debris disc by the system. A violent chaotic evolution of the planets can easily clear leftover planetesimal belts preventing the ignition of a substantial collisional cascade that can give origin to a debris disc. On the other end, a mild evolution with limited steps in eccentricity and semimajor axis can trigger the formation of a debris disc by stirring an initially quiet planetesimal belt. The variety of possible effects that planet-planet scattering can have on the formation of debris discs is analysed and the statistical probability of the different outcomes is evaluated. This leads to the prediction that systems which underwent an episode of chaotic evolution might have a lower probability of harbouring a debris disc.
Solov'eva, O A; Storozheva, Z I; Proshin, A T; Sherstnev, V V
2011-02-01
Effect of administration of selective N-methyl-D-aspartate (NMDA) receptor antagonist Ro 25-6981 on learning and memory in a dose which is known to stimulate neoneurogenesis was assessed in adult rats with different abilities to formation of spatial skills in different time periods after the antagonist injection. Wistar male rats were trained to find hidden platform in the Morris water maze for 5 consecutive days. Rats' learning ability for spatial skill formation was evaluated depending on platform speed achievements. In re-training sessions (cues and platform location changed), it was found that all rats received Ro 25-6981 13 days before the re-training demonstrated impaired spatial memory. At the same time the inhibitor injected 29 days before re-training selectively facilitated the formation of spatial skill in animals with initially low learning abilities.
Zhuge, Qunbi; Morsy-Osman, Mohamed; Chagnon, Mathieu; Xu, Xian; Qiu, Meng; Plant, David V
2014-02-10
In this paper, we propose a low-complexity format-transparent digital signal processing (DSP) scheme for next generation flexible and energy-efficient transceiver. It employs QPSK symbols as the training and pilot symbols for the initialization and tracking stage of the receiver-side DSP, respectively, for various modulation formats. The performance is numerically and experimentally evaluated in a dual polarization (DP) 11 Gbaud 64QAM system. Employing the proposed DSP scheme, we conduct a system-level study of Tb/s bandwidth-adaptive superchannel transmissions with flexible modulation formats including QPSK, 8QAM and 16QAM. The spectrum bandwidth allocation is realized in the digital domain instead of turning on/off sub-channels, which improves the performance of higher order QAM. Various transmission distances ranging from 240 km to 6240 km are demonstrated with a colorless detection for hardware complexity reduction.
Excimer laser annealing: A gold process for CZ silicon junction formation
NASA Technical Reports Server (NTRS)
Wong, David C.; Bottenberg, William R.; Byron, Stanley; Alexander, Paul
1987-01-01
A cold process using an excimer laser for junction formation in silicon has been evaluated as a way to avoid problems associated with thermal diffusion. Conventional thermal diffusion can cause bulk precipitation of SiOx and SiC or fail to completely activate the dopant, leaving a degenerate layer at the surface. Experiments were conducted to determine the feasibility of fabricating high quality p-n junctions using a pulsed excimer laser for junction formation at remelt temperature with ion-implanted surfaces. Solar-cell efficiency exceeding 16 percent was obtained using Czochralski single-crystal silicon without benefit of back surface field or surface passivation. Characterization shows that the formation of uniform, shallow junctions (approximately 0.25 micron) by excimer laser scanning preserves the minority carrier lifetime that leads to high current collection. However, the process is sensitive to initial surface conditions and handling parameters that drive the cost up.
Experimental models for cancellous bone healing in the rat
Bernhardsson, Magnus; Sandberg, Olof; Aspenberg, Per
2015-01-01
Background and purpose — Cancellous bone appears to heal by mechanisms different from shaft fracture healing. There is a paucity of animal models for fractures in cancellous bone, especially with mechanical evaluation. One proposed model consists of a screw in the proximal tibia of rodents, evaluated by pull-out testing. We evaluated this model in rats by comparing it to the healing of empty drill holes, in order to explain its relevance for fracture healing in cancellous bone. To determine the sensitivity to external influences, we also compared the response to drugs that influence bone healing. Methods — Mechanical fixation of the screws was measured by pull-out test and related to the density of the new bone formed around similar, but radiolucent, PMMA screws. The pull-out force was also related to the bone density in drill holes at various time points, as measured by microCT. Results — The initial bone formation was similar in drill holes and around the screw, and appeared to be reflected by the pull-out force. Both models responded similarly to alendronate or teriparatide (PTH). Later, the models became different as the bone that initially filled the drill hole was resorbed to restore the bone marrow cavity, whereas on the implant surface a thin layer of bone remained, making it change gradually from a trauma-related model to an implant fixation model. Interpretation — The similar initial bone formation in the different models suggests that pull-out testing in the screw model is relevant for assessment of metaphyseal bone healing. The subsequent remodeling would not be of clinical relevance in either model. PMID:26200395
Geng, Hongjuan; Yuan, Yang; Adayi, Aidina; Zhang, Xu; Song, Xin; Gong, Lei; Zhang, Xi; Gao, Ping
2018-01-01
Titanium (Ti) implants have been commonly used in oral medicine. However, despite their widespread clinical application, these implants are susceptible to failure induced by microbial infection due to bacterial biofilm formation. Immobilization of chimeric peptides with antibacterial properties on the Ti surface may be a promising antimicrobial approach to inhibit biofilm formation. Here, chimeric peptides were designed by connecting three sequences (hBD-3-1/2/3) derived from human β-defensin-3 (hBD-3) with Ti-binding peptide-l (TBP-l: RKLPDAGPMHTW) via a triple glycine (G) linker to modify Ti surfaces. Using X-ray photoelectron spectroscopy (XPS), the properties of individual domains of the chimeric peptides were evaluated for their binding activity toward the Ti surface. The antimicrobial and anti-biofilm efficacy of the peptides against initial settlers, Streptococcus oralis (S. oralis), Streptococcus gordonii (S. gordonii) and Streptococcus sanguinis (S. sanguinis), was evaluated with confocal laser scanning microscopy (CLSM) and scanning electron microscopy (SEM). Transmission electron microscopy (TEM) and real-time quantitative PCR (qRT-PCR) were used to study cell membrane changes and the underlying antimicrobial mechanism. Compared with the other two peptides, TBP-1-GGG-hBD3-3 presented stronger antibacterial activity and remained stable in saliva and serum. Therefore, it was chosen as the best candidate to modify Ti surfaces in this study. This peptide inhibited the growth of initial streptococci and biofilm formation on Ti surfaces with no cytotoxicity to MC3T3-E1 cells. Disruption of the integrity of bacterial membranes and decreased expression of adhesion protein genes from S. gordonii revealed aspects of the antibacterial mechanism of TBP-1-GGG-hBD3-3. We conclude that engineered chimeric peptides with antimicrobial activity provide a potential solution for inhibiting biofilm formation on Ti surfaces to reduce or prevent the occurrence of peri-implant diseases. Copyright © 2017 Elsevier B.V. All rights reserved.
Data presentation techniques for rotating machinery malfunction diagnosis
NASA Technical Reports Server (NTRS)
Spettel, T.
1985-01-01
Baseline steady state data is excellent for documentation of vibration signals at normal operating conditions. Assuming that a set of initial data was acquired with the machinery in a good state of repair, any future changes or deterioration in mechanical condition can be easily compared to the baseline information. Often this type of comparison will yield sufficient information for evaluation of the problem. However, many malfunctions require the analysis of transient data in order to identify the malfunction. Steady-state data formats consist of: Time Base Waveform, Orbit, Spectrum. Transient data formats consist of: Polar, Bode, Cascade. Our objective is to demonstrate the use of the above formats to diagnose a machine malfunction. A turbine-driven compressor train is chosen as an example. The machine train outline drawing is shown.
Core formation in the Moon: The mystery of the excess depletion of Mo, W and P
NASA Technical Reports Server (NTRS)
Newsom, H. E.; Maehr, S. A.
1993-01-01
We have evaluated siderophile element depletion models for the Moon in light of our improved statistical treatment of siderophile element abundance data and new information on the physics of core formation. If core formation occurred in the Moon at the large degrees of partial melting necessary for metal segregation, according to recent estimates, then a significant inconsistency (not seen in the eucrite parent body) exists in the depletion of the incompatible siderophile elements Mo, W, and P, compared to other siderophile elements in the Moon. The siderophile data, with the exception of Mo, are most consistent with terrestrial initial siderophile abundances and segregation of a very small core in the Moon. Our improved abundance estimates and possible explanations for these discrepancies are discussed.
Acne Scarring—Pathogenesis, Evaluation, and Treatment Options
Connolly, Deirdre; Vu, Ha Linh; Mariwalla, Kavita
2017-01-01
Acne vulgaris is a ubiquitous problem affecting 80 percent of people ages 11 to 30 years, with many patients experiencing some degree of scarring. This review focuses on atrophic scars, the most common type of acne scar. We briefly address the cellular sequelae that lead to scar formation and the initial evaluation of patients with acne scars. We then discuss an algorithmic approach to the treatment of acne scarring based on the classification of scars into erythematous and atrophic types. Lastly, we discuss the future treatment of acne scars and ongoing clinical trials. PMID:29344322
Matsuda, Yuko; Cho, Otomi; Sugita, Takashi; Ogishima, Daiki; Takeda, Satoru
2018-03-30
Vulvovaginal candidiasis (VVC) is a common superficial infection of the vaginal mucous membranes caused by the fungus Candida albicans. The aim of this study was to assess the mechanisms underlying the inhibitory effects of the culture supernatants of Lactobacillus gasseri and L. crispatus, the predominant microbiota in Asian healthy women, on C. albicans biofilm formation. The inhibition of C. albicans adhesion to HeLa cells by Lactobacillus culture supernatant was also investigated. Candida albicans biofilm was formed on polystyrene flat-bottomed 96-well plates, and the inhibitory effects on the initial colonization and maturation phases were determined using the XTT reduction assay. The expression levels of biofilm formation-associated genes (HWP1, ECE1, ALS3, BCR1, EFG1, TEC1, and CPH1) were determined by reverse transcription quantitative polymerase chain reaction. The inhibition of C. albicans adhesion to HeLa cells by Lactobacillus culture supernatant was evaluated by enumerating viable C. albicans cells. The culture supernatants of both Lactobacillus species inhibited the initial colonization and maturation of C. albicans biofilm. The expression levels of all biofilm formation-related genes were downregulated in the presence of Lactobacillus culture supernatant. The culture supernatant also inhibited C. albicans adhesion to HeLa cells. The culture supernatants of L. gasseri and L. crispatus inhibited C. albicans biofilm formation by downregulating biofilm formation-related genes and C. albicans adhesion to HeLa cells. These findings support the notion that Lactobacillus metabolites may be useful alternatives to antifungal drugs for the management of VVC.
Alexander N. Kapich; Tatyana V. Korneichik; Kenneth E. Hammel; Annele Hatakka
2011-01-01
The peroxidation of C18 unsaturated fatty acids by fungal manganese peroxidase (MnP)/Mn(II) and by chelated Mn(III) was studied with application of three different methods: by monitoring oxygen consumption, by measuring conjugated dienes and by thiobarbituric acid-reactive substances (TBARS) formation. All tested polyunsaturated fatty acids (PUFAs) were oxidized by MnP...
Cook, Joan M.; O’Donnell, Casey; Dinnen, Stephanie; Bernardy, Nancy; Rosenheck, Robert; Desai, Rani
2013-01-01
Thirty-eight U.S. Department of Veterans Affairs (VA) residential treatment programs for posttraumatic stress disorder (PTSD) participated in a formative evaluation of their programmatic services, including evidenced-based treatments (EBTs), between July 2008 and March 2011. Face-to-face qualitative interviews were conducted with over 250 staff by an independent psychologist along with on-site participant observations. This evaluation coincided with a national VA dissemination initiative to train providers in two EBTs for PTSD, Prolonged Exposure (PE) and Cognitive Processing Therapy (CPT). A substantial proportion of eligible (based on professional background) residential treatment providers received training in PE (37.4%) or CPT (64.2%), with 9.5% completing case consultation or becoming national trainers in each therapy respectively. In semi-structured interviews, providers reported that their clinical programs had adopted these EBTs at varying levels ranging from no adoption to every patient receiving the full protocol. Suggestions for improving the adoption of PE and CPT are noted, including distilling manualized treatments to essential common elements. PMID:23417875
Pragmatic Applications of RE-AIM for Health Care Initiatives in Community and Clinical Settings
Estabrooks, Paul E.
2018-01-01
The RE-AIM (Reach Effectiveness Adoption Implementation Maintenance) planning and evaluation framework has been applied broadly, but users often have difficulty in applying the model because of data collection needs across multiple domains and sources. Questions in the more common “who, what, where, how, when, and why” format may be an effective guide to ensure that individual participants, organization staff, and the perspectives of the setting are considered in planning and evaluation. Such a format can also help users in typical community and clinical settings to identify which outcomes are most valued and to focus limited measurement resources. Translations of RE-AIM that are easy to understand and apply are needed for application in real-world community and clinical settings where research and evaluation resources are limited. The purpose of this article is to provide simplified, pragmatic, user-centered and stakeholder-centered recommendations to increase the use of RE-AIM in community and clinical settings and in translational research. PMID:29300695
Initiation of small-satellite formations via satellite ejector
NASA Astrophysics Data System (ADS)
McMullen, Matthew G
Small satellites can be constructed at a fraction of the cost of a full-size satellite. One full-size satellite can be replaced with a multitude of small satellites, offering expanded area coverage through formation flight. However, the shortcoming to the smaller size is usually a lack of thrusting capabilities. Furthermore, current designs for small satellite deployment mechanisms are only capable of love deployment velocities (on the order of meters per second). Motivated to address this shortcoming, a conceived satellite ejector would offer a significant orbit change by ejecting the satellite at higher deployment velocities (125-200 m/s). Focusing on the applications of the ejector, it is sought to bridge the gap in prior research by offering a method to initiate formation flight. As a precursor to the initiation, the desired orbit properties to initiate the formation are specified in terms of spacing and velocity change vector. From this, a systematic method is developed to find the relationship among velocity change vector, the desired orbit's orientation, and the spacing required to initiate the formation.
Space shuttle launch era spacecraft injection errors and DSN initial acquisition
NASA Technical Reports Server (NTRS)
Khatib, A. R.; Berman, A. L.; Wackley, J. A.
1981-01-01
The initial acquisition of a spacecraft by the Deep Space Network (DSN) is a critical mission event. This results from the importance of rapidly evaluating the health and trajectory of a spacecraft in the event that immediate corrective action might be required. Further, the DSN initial acquisition is always complicated by the most extreme tracking rates of the mission. The DSN initial acquisition characteristics will change considerably in the upcoming space shuttle launch era. How given injection errors at spacecraft separation from the upper stage launch vehicle (carried into orbit by the space shuttle) impact the DSN initial acquisition, and how this information can be factored into injection accuracy requirements to be levied on the Space Transportation System (STS) is addressed. The approach developed begins with the DSN initial acquisition parameters, generates a covariance matrix, and maps this covariance matrix backward to the spacecraft injection, thereby greatly simplifying the task of levying accuracy requirements on the STS, by providing such requirements in a format both familiar and convenient to STS.
Chemistry of fuel deposits and sediments and their predursors
NASA Technical Reports Server (NTRS)
Mayo, F. R.; Lan, B. Y.; Buttrill, S. E., Jr.; St.john, G. A.
1984-01-01
The mechanism of solid deposit formation on hot engine parts from turbine fuels is investigated. Deposit formation is associated with oxidation of the hydrocarbon fuel. Therefore, oxidation rates and soluble gum formation were measured for several jet turbine fuels and pure hydrocarbon mixtures. Experiments were performed at 130 C using thermal initiation and at 100 C using ditertiary butyl peroxide as a chemical initiator. Correlation of the data shows that the ratio of rate of oxidation to rate of gum formation for a single fuel is not much affected by experimental conditions, even though there are differences in the abilities of different hydrocarbons to initiate and continue the oxidation. This indicates a close association of gum formation with the oxidation process. Oxidations of n-dodecane, tetralin and the more unstable jet fuels are autocatalytic, while those of 2-ethylnaphthalene and a stable jet fuel are self-retarding. However, the ratio of oxidation rate to gum formation rate appear to be nearly constant for each substrate. The effect of oxygen pressure on gum and oxidation formation was also studied. Dependence of gum formation on the concentration of initiator at 100 C is discussed and problems for future study are suggested.
Initialization of distributed spacecraft for precision formation flying
NASA Technical Reports Server (NTRS)
Hadaegh, F. Y.; Scharf, D. P.; Ploen, S. R.
2003-01-01
In this paper we present a solution to the formation initialization problem for N distributed spacecraft located in deep space. Our solution to the FI problem is based on a three-stage sky search procedure that reduces the FI problem for N spacecraft to the simpler problem of initializing a set of sub-formations. We demonstrate our FI algorithm in simulation using NASA's five spacecraft Terrestrial Planet Finder mission as an example.
Secret, Mary; Abell, Melissa L; Berlin, Trey
2011-01-01
The authors present a set of guiding principles and strategies to facilitate the collaborative efforts of social work researchers and practitioners as they initiate, design, and implement outcome evaluations of human service interventions and programs. Beginning with an exploration of the interpersonal barriers to practice-research collaborations, and building on their experiences in successfully completing a community-based research evaluation, the authors identify specific relationship-focused principles and strategies and illustrate how these approaches can guide practice-research teams through the various sequential activities of the evaluation research process. In particular, it is suggested that practice-research collaborations can be formed, strengthened, and sustained by emphasis on a spirit of discovery and shared leadership at the start of the relationship, use of a comprehensive evaluation model to clarify and frame the evaluation and program goals, beginning where the client is when selecting research methodology and measurement tools, commitment to keeping the program first and recording everything during the implementation and data-collection stages, discussion of emerging findings and presentation of findings in graphic format at the data-analysis stage, and a total team approach at the dissemination stage.
Outcome evaluation of a 3-year senior health and wellness initiative.
Kuczmarksi, Marie Fanelli; Cotugna, Nancy
2009-02-01
The Wilmington Senior Center developed a 3-year multidisciplinary health and wellness initiative entitled The Time of Your Life to promote healthy aging for participants attending countywide senior centers. The purpose of this paper is to describe the development and implementation of the evaluation methodology and outcomes of this senior health and wellness project that consisted of 11 programs in total. Long-term programming can present several challenges in both implementation and evaluation, but assessing outcomes is critical to documenting program value and accountability. Participant-completed surveys and post-series focus groups were utilized as the evaluation tools. Our findings indicate that the program's objectives of increasing knowledge and motivating adoption or maintenance of a healthy lifestyle were met to varying degrees, while a third objective of assessing the usefulness of resources to inform health-related decisions was unable to be evaluated due to the cross-sectional nature of the data collection. Post-series focus groups indicated that topics of most interest to seniors were money management, medications and staying mentally and physically fit. The evaluations showed that long-term programming, while challenging, can be a successful and sustainable format for senior health education.
Méndez Rojano, Rodrigo; Mendez, Simon; Nicoud, Franck
2018-06-01
Thrombosis is a major concern in blood-coated medical devices. Contact activation, which is the initial part of the coagulation cascade in device-related thrombosis, is not considered in current thrombus formation models. In the present study, pro-coagulant reactions including the contact activation system are coupled with a fluid solver in order to evaluate the potential of the contact system to initiate thrombin production. The biochemical/fluid model is applied to a backward-facing step configuration, a flow configuration that frequently appears in medical devices. In contrast to the in vivo thrombosis models in which a specific thrombotic zone (injury region) is set a priori by the user to initiate the coagulation reaction, a reactive surface boundary condition is applied to the whole device wall. Simulation results show large thrombin concentration in regions related to recirculation zones without the need of an a priori knowledge of the thrombus location. The numerical results align well with the regions prone to thrombosis observed in experimental results reported in the literature. This approach could complement thrombus formation models that take into account platelet activity and thrombus growth to optimize a wide range of medical devices.
Young, Laura; Anderson, Jennifer; Beckstrom, Leslie; Bellows, Laura; Johnson, Susan L
2004-01-01
Within the field of nutrition education, social marketing has become a promising framework to systematically approach problems related to nutrition behavior. In 1997, the Colorado Nutrition Network began developing a social marketing campaign to promote healthful food choices among low-income Coloradans. A multifaceted formative evaluation plan that included focus groups, campaign concept pretesting, and a food frequency questionnaire was used to segment and scrutinize the target audience. The resulting pilot program was a blend of educational and marketing strategies targeting preschoolers that was implemented in Head Start classrooms. The 12-week intervention contained a narrow, behavior-based "try new foods" message, multiple nutrition education activities, and repeated opportunities to taste 13 novel foods. Key strategies used and findings from the formative evaluation process are presented herein in an effort to provide insight for nutrition educators interested in developing similar interventions.
NASA Astrophysics Data System (ADS)
Li, R.; Li, W. B.; Wang, X. M.; Li, W. B.
2018-03-01
The effects of the initiation diameter and synchronicity error on the formation of fins and stable-flight velocity of an explosively formed projectile (EFP) with three-point initiation are investigated. The pressure and area of the Mach wave acting on the metal liner at different initiation diameters are calculated employing the Whitham method. LS-DYNA software is used to investigate the asymmetric collision of detonation waves resulting from three-point initiation synchronicity error, the distortion characteristics of the liner resulting from the composite detonation waves, and the performance parameters of the EFP with fins. Results indicate that deviations of the Y-shaped high-pressure zone and central ultrahigh-pressure zone from the liner center can be attributed to the error of three-point initiation, which leads to the irregular formation of EFP fins. It is noted that the area of the Mach wave decreases, but the pressure of the Mach wave and the final speed and length-to-diameter ( L/ D) ratio of the EFP increase, benefiting the formation of the EFP fins, as the initiation diameter increases.
TESSX: A Mission for Space Exploration with Tethers
NASA Technical Reports Server (NTRS)
Cosmo, Mario L.; Lorenzini, Enrico C.; Gramer, Daniel J.; Hoffman, John H.; Mazzoleni, Andre P.
2005-01-01
Tethers offer significant potential for substantially increasing payload mass fraction, increasing spacecraft lifetime, enhancing long-term space travel, and enabling the understanding and development of gravity-dependent technologies required for Moon and Mars exploration. The development of the Tether Electrodynamic Spin-up and Survivability Experiment (TESSX) will support applications relevant to NASA's new exploration initiative, including: artificial gravity generation, formation flying, electrodynamic propulsion, momentum exchange, and multi-amp current collection and emission. Under the broad term TESSX, we are currently evaluating several different tether system configurations and operational modes. The initial results of this work are presented, including hardware development, orbital dynamics simulations, and electrodynamics design and analysis.
Development and evaluation of an electronic drug and therapeutics bulletin.
Alderman, Christopher P
2002-10-01
To describe the development, implementation, and initial evaluation of a paperless drug and therapeutics bulletin that is distributed by electronic mail from the pharmacy department of an Australian teaching hospital. A standardized format for the bulletin was designed and approved in February 2001. The aim of the bulletin is to facilitate the timely dissemination of concise, factual information about issues of current interest in therapeutics, drug safety, and the cost-effective use of medicines. A simple and attractive graphic design was chosen, and the hospital's clinical pharmacists and drug information staff developed an initial bank of content during the period immediately preceding the launch. The bulletin is presented as a 1-page, read-only file in Word for Windows format and was initially distributed by electronic mail to all users of the hospital's computerized communication network. As the popularity of the bulletin increased, healthcare practitioners from outside of the hospital began to request permission for inclusion on the circulation list, and the content was frequently forwarded by E-mail to workers in other hospitals and community-based settings. The bulletin is now distributed to pharmacists around Australia via 2 separate moderated discussion lists, one of which provides an archive site for previous editions. Healthcare workers in Singapore, the US, Canada, and New Zealand also receive the bulletin, which is now also abstracted by a major Australian pharmacy journal. A readership survey (also electronically distributed) was used to seek feedback after the publication of the first 12 editions. Readers indicated a high level of satisfaction with the content, format, and frequency of distribution of the materials. Although the concept and execution of this project was relatively simple, an extensive literature review did not reveal any previously published reports describing this type of approach to the distribution of a pharmacy bulletin. The development and implementation of the electronic drug and therapeutics bulletin has provided an opportunity to use modern communication technology to promote safe and effective medication use and appears to have been well received.
Bach, Long Giang; Islam, Md Rafiqul; Vo, Thanh-Sang; Kim, Se-Kwon; Lim, Kwon Taek
2013-03-15
Hydroxyapatite nanocrystals (HAP NCs) were encapsulated by poly(allyl methacrylate) (PolyAMA) employing controlled surface-initiated reversible addition-fragmentation chain transfer (SI-RAFT) polymerization of allyl methacrylate to afford HAP-PolyAMA nanohybrids. The subsequent thiol-ene coupling of nanohybrids with 2-mercaptosuccinic acid resulted HAP-Poly(AMA-COOH) possessing multicarboxyl group. The formation of the nanohybrids was confirmed by FT-IR and EDS analyses. The TGA and FE-SEM investigation were further suggested the grafting of PolyAMA onto HAP NCs. The utility of the HAP-PolyAMA nanohybrid as drug carrier was also explored. The pendant carboxyl groups on the external layers of nanohybrids were conjugated with anticancer drug cisplatin to afford HAP-Poly(AMA-COOH)/Pt complex. The formation of the complex was confirmed by FT-IR, XPS, and FE-SEM. In vitro evaluation of the synthesized complex as nanomedicine revealed its potential chemotherapeutic efficacy against cancer cell lines. Copyright © 2012 Elsevier Inc. All rights reserved.
Enhanced dimethyl phthalate biodegradation by accelerating phthalic acid di-oxygenation.
Tang, Yingxia; Zhang, Yongming; Jiang, Ling; Yang, Chao; Rittmann, Bruce E
2017-12-01
The aerobic biodegradation of dimethyl phthalate (DMP) is initiated with two hydrolysis reactions that generate an intermediate, phthalic acid (PA), that is further biodegraded through a two-step di-oxygenation reaction. DMP biodegradation is inhibited when PA accumulates, but DMP's biodegradation can be enhanced by adding an exogenous electron donor. We evaluated the effect of adding succinate, acetate, or formate as an exogenous electron donor. PA removal rates were increased by 15 and 30% for initial PA concentrations of 0.3 and 0.6 mM when 0.15 and 0.30 mM succinate, respectively, were added as exogenous electron donor. The same electron-equivalent additions of acetate and formate had the same acceleration impacts on PA removal. Consequently, the DMP-removal rate, even PA coexisting with DMP simultaneously, was accelerated by 37% by simultaneous addition of 0.3 mM succinate. Thus, lowering the accumulation of PA by addition of an electron increased the rate of DMP biodegradation.
NASA Astrophysics Data System (ADS)
Nitta, Noriko; Taniwaki, Masafumi
2006-04-01
The present authors proposed a novel nano-fabrication technique that is able to arrange the fine cells orderly, based on their finding in GaSb implanted at a low temperature. In this article, first the experimental results that anomalous cellular structure was formed in GaSb by ion implantation is introduced and the self-organizational formation mechanism of the structure is described. Next a nano-fabrication technique that utilizes focused ion beam is described. This technique consists of two procedures, i.e. the formation process of the voids array and the development of the initial array to ordered cellular structure. Finally, the nano-fabrication is actually performed by this technique and their results are reported. Fabrication succeeded in structures where the dot (cell) interval was 100 nm or larger. The minimum ion dose for initial voids which develops to the ordered cellular structure is evaluated. It is also shown that the substrate temperature during implantation is an essential parameter for this technique.
A new approach to large area microchannel plate manufacture
NASA Technical Reports Server (NTRS)
1986-01-01
Methods of manufacture of twisted single elements as the base for producing microchannel plates (MCP) are discussed. Initial evaluations validated the off-axis channel concept and no technological roadblocks were identified which would prevent fabrication of high gain, high spatial resolution, large format MCP's using this technique. The first MP's have operated at stable gains of 3 million with pulse height resolution superior to results obtained by standard chevron MCP's.
The formation of nickel sulfides has been examined experimentally over the temperature range from 25 to 60°C. At all conditions studied, hexagonal (α-NiS) was the initial precipitate from solution containing Ni2+ and dissolved sulfide. The formation of millerite (β- NiS, rhombo...
Efficacy of a mouthrinse based on hydroxyapatite to reduce initial bacterial colonisation in situ.
Kensche, A; Holder, C; Basche, S; Tahan, N; Hannig, C; Hannig, M
2017-08-01
The present in situ - investigation aimed to specify the impact of pure hydroxyapatite microclusters on initial bioadhesion and bacterial colonization at the tooth surface. Pellicle formation was carried out in situ on bovine enamel slabs (9 subjects). After 1min of pellicle formation rinses with 8ml of hydroxyapatite (HA) microclusters (5%) in bidestilled water or chlorhexidine 0.2% were performed. As negative control no rinse was adopted. In situ biofilm formation was promoted by the intraoral slab exposure for 8h overnight. Afterwards initial bacterial adhesion was quantified by DAPI staining and bacterial viability was determined in vivo/in vitro by live/dead-staining (BacLight). SEM analysis evaluated the efficacy of the mouthrinse to accumulate hydroxyapatite microclusters at the specimens' surface and spit-out samples of the testsolution were investigated by TEM. Compared to the control (2.36×10 6 ±2.01×10 6 bacteria/cm 2 ), significantly reduced amounts of adherent bacteria were detected on specimens rinsed with chlorhexidine 0.2% (8.73×10 4 ±1.37×10 5 bacteria/cm 2 ) and likewise after rinses with the hydroxyapatite testsolution (2.08×10 5 ±2.85×10 5 bacteria/cm 2 , p<0.001). No demonstrable effect of HA-particles on Streptococcus mutans viability could be shown. SEM analysis confirmed the temporary adsorption of hydroxyapatite microclusters at the tooth surface. Adhesive interactions of HA-particles with oral bacteria were shown by TEM. Hydroxyapatite microclusters reduced initial bacterial adhesion to enamel in situ considerably and could therefore sensibly supplement current approaches in dental prophylaxis. Copyright © 2017 Elsevier Ltd. All rights reserved.
Relative Positioning Evaluation of a Tetrahedral Flight Formation’s Satellites
NASA Astrophysics Data System (ADS)
Mahler, W. F. C.; Rocco, E. M.; Santos, D. P. S.
2017-10-01
This paper presents a study about the tetrahedral layout of four satellites in a way that every half-orbital period this set groups together while flying in formation. The formation is calculated analyzing the problem from a geometrical perspective and disposed by precisely adjusting the orbital parameters of each satellite. The dynamic modelling considers the orbital motion equations. The results are analyzed, compared and discussed. A detection algorithm is used as flag to signal the regular tetrahedron’s exact moments of occurrence. To do so, the volume calculated during the simulation is compared to the real volume, based on the initial conditions of the exact moment of formation and respecting a tolerance. This tolerance value is stablished arbitrarily depending on the mission and the formation’s geometrical parameters. The simulations will run on a computational environment.
McElwain, Alyssa; Finnegan, Vanessa; Whittaker, Angela; Kerpelman, Jennifer; Adler-Baeder, Francesca; Duke, Adrienne
2016-10-01
Adolescent romantic relationships are known to have a significant impact on individual well-being and development. However, few teens experience formal education about the knowledge and skills necessary for building healthy romantic relationships. In response, a statewide relationship education initiative was developed at a large university in a Southeastern state. Undergraduates who enrolled in a service learning course in Human Development and Family Studies partnered with this initiative and implemented a relationship education program targeting high school students. A service learning model is used in this initiative because it offers opportunities for students' professional development and experiential learning. The present article provides a formative and illustrative summative evaluation of the service learning program. Specifically, the primary aims of this paper are to 1) provide an overview of the service learning course components; 2) describe preparation of the service learning students and their implementation of the relationship education program; 3) discuss challenges and lessons learned; and 4) offer initial evidence of effectiveness by showing change in targeted outcomes for the high school student recipients of the relationship education program. Copyright © 2016 Elsevier Ltd. All rights reserved.
Kang, T W; Lee, M W; Hye, M J; Song, K D; Lim, S; Rhim, H; Lim, H K; Cha, D I
2014-12-01
To evaluate the technical feasibility of artificial ascites formation using an angiosheath before percutaneous radiofrequency ablation (RFA) for hepatic tumours and to determine predictive factors affecting the technical failure of artificial ascites formation. This retrospective study was approved by the institutional review board. One hundred and thirteen patients underwent percutaneous RFA of hepatic tumours after trying to make artificial ascites using an angiosheath to avoid collateral thermal damage. The technical success rate of making artificial ascites using an angiosheath and conversion rate to other techniques after initial failure of making artificial ascites were evaluated. The technical success rate for RFA was assessed. In addition, potential factors associated with technical failure including previous history of transcatheter arterial chemoembolization (TACE) or RFA, type of abdominal surgery, and adjacent perihepatic structures were reviewed. Predictive factors for the technical failure of artificial ascites formation were analysed using multivariate analysis. The technical success rates of artificial ascites formation by angiosheath and that of RFA were 84.1% (95/113) and 97.3% (110/113), respectively. The conversion rate to other techniques after the failure of artificial ascites formation using an angiosheath was 15.9% (18/113). Previous hepatic resection was the sole independent predictive factor affecting the technical failure of artificial ascites formation (p<0.001, odds ratio = 29.03, 95% confidence interval: 4.56-184.69). Making artificial ascites for RFA of hepatic tumours using an angiosheath was technically feasible in most cases. However, history of hepatic resection was a significant predictive factor affecting the technical failure of artificial ascites formation. Copyright © 2014 The Royal College of Radiologists. Published by Elsevier Ltd. All rights reserved.
LeBlanc, Blaise W; Eggleston, Gillian; Sammataro, Diana; Cornett, Charles; Dufault, Renee; Deeby, Thomas; St Cyr, Eldwin
2009-08-26
In the United States, high-fructose corn syrup (HFCS) has become a sucrose replacement for honey bees and has widespread use as a sweetener in many processed foods and beverages for human consumption. It is utilized by commercial beekeepers as a food for honey bees for several reasons: to promote brood production, after bees have been moved for commercial pollination, and when field-gathered nectar sources are scarce. Hydroxymethylfurfural (HMF) is a heat-formed contaminant and is the most noted toxin to honey bees. Currently, there are no rapid field tests that would alert beekeepers of dangerous levels of HMF in HFCS or honey. In this study, the initial levels and the rates of formation of HMF at four temperatures were evaluated in U.S.-available HFCS samples. Different HFCS brands were analyzed and compared for acidity and metal ions by inductively coupled plasma mass spectroscopy. Levels of HMF in eight HFCS products were evaluated over 35 days, and the data were fit to polynomial and exponential equations, with excellent correlations. The data can be used by beekeepers to predict HMF formation on storage. Caged bee studies were conducted to evaluate the HMF dose-response effect on bee mortality. Finally, commercial bases such as lime, potash, and caustic soda were added to neutralize hydronium ion in HMF samples, and the rates of HMF formation were compared at 45 degrees C.
Arai, Toshiaki; Ochiai, Kuniyasu; Senpuku, Hidenobu
2015-02-01
Actinomyces naeslundii is an early colonizer with important roles in the development of the oral biofilm. The effects of butyric acid, one of short chain fatty acids in A. naeslundii biofilm formation was observed using a flow cell system with Tryptic soy broth without dextrose and with 0.25% sucrose (TSB sucrose). Significant biofilms were established involving live and dead cells in TSB sucrose with 60mM butyric acid but not in concentrations of 6, 30, 40, and 50mM. Biofilm formation failed in 60mM sodium butyrate but biofilm level in 60mM sodium butyrate (pH4.7) adjusted with hydrochloric acid as 60mM butyric media (pH4.7) was similar to biofilm levels in 60mM butyric acid. Therefore, butyric acid and low pH are required for significant biofilm formation in the flow cell. To determine the mechanism of biofilm formation, we investigated initial A. naeslundii colonization in various conditions and effects of anti-GroEL antibody. The initial colonization was observed in the 60mM butyric acid condition and anti-GroEL antibody inhibited the initial colonization. In conclusion, we established a new biofilm formation model in which butyric acid induces GroEL-dependent initial colonization of A. naeslundii resulting in significant biofilm formation in a flow system. Copyright © 2014 Elsevier B.V. All rights reserved.
You, Fang; Dalal, Ram; Huang, Longbin
2018-08-01
Field evidence has been scarce about soil (or technosol) formation and direct phytostabilization of base metal mine tailings under field conditions. The present study evaluated key attributes of soil formation in weathered and neutral Cu-Pb-Zn tailings subject to organic amendment (WC: woodchips) and colonization of pioneer native plant species (mixed native woody and grass plant species) in a 2.5-year field trial under subtropical and semi-arid climatic conditions. Key soil indicators of engineered soil formation process were characterized, including organic carbon fractions, aggregation, microbial community and key enzymatic activities. The majority (64-87%) of the OC was stabilized in microaggregate or organo-mineral complexes in the amended tailings. The levels of OC and water soluble OC were elevated by 2-3 folds across the treatments, with the highest level in the treatment of WC and plant colonization (WC+P). Specifically, the WC+P treatment increased the proportion of water stable macroaggregates. Plants further contributed to the N rich organic matter in the tailings, favouring organo-mineral interactions and organic stabilization. Besides, the plants played a major role in boosting microbial biomass and activities in the treated tailings. WC and plants enhanced the contents of organic carbon (OC) associated with aggregates (e.g., physically protected OC), formation of water-stable aggregates (e.g., micro and macroaggregates), chemical buffering capacity (e.g., cation exchange capacity). Microbial community and enzymatic activities were also stimulated in the amended tailings. The present results showed that the formation of functional technosol was initiated in the eco-engineered and weathered Cu-Pb-Zn tailings under field conditions for direct phytostabilization. Copyright © 2018 Elsevier Ltd. All rights reserved.
Risk Factors for Inhibitor Formation in Hemophilia: A Prevalent Case-Control Study
Ragni, Margaret V.; Ojeifo, Oluseyi; Feng, Jinong; Yan, Jin; Hill, Kathleen A.; Sommer, Steve S.; Trucco, Massimo N.; Brambilla, Donald J.
2009-01-01
Background Inhibitor formation is a major complication of hemophilia treatment. Aim In a prevalent case-control study, we evaluated blood product exposure, genotype, and HLA type on hemophilia A inhibitor formation. Methods Product exposure was extracted from medical records. Genotype was determined on stored DNA samples by detection of virtually all mutations-SSCP (DOVAM-S) and subcycling PCR. HLA typing was performed by PCR amplification and exonuclease-released fluorescence. Results Cases experienced higher intensity factor, 455 vs. 200 U per exposure, p<0.005, more frequent central nervous system (CNS) bleeding, 7 of 20 (35.0%) vs. 1 of 57 (1.7%), p=0.001, and more commonly from inhibitor families, 7 of 20 (35.0%) vs. 0 of 57 (0%), p<0.001, and African-American, 12 of 63 (19.0%) vs. 6 of 117 (5.1%), p=0.015. Among the latter, CNS bleeding was more commonly the initial bleed, 60% vs. 0%, p<0.001, and survival was shorter, 14 vs. 38 yr, p=0.025. Inhibitor formation was uncommon in those with missense mutations, 2 of 65 (3.1%) vs. 31 of 119 (26.0%), p=0.008, and unrelated to factor VIII immunogenic epitope, p=0.388, or HLA type, p>0.100. Genotype was not associated with race. Time to immune tolerance was shorter for titers < 120 vs. ≥ 120 BU/ml, 6 vs. 16 months, p<0.01, but unaffected by tolerizing dose regimen, p>0.50. Conclusions Inhibitor formation is associated with high intensity product exposure, CNS bleeding, African-American race, and low frequency of missense mutations. The ideal time to initiate prophylaxis to reduce CNS bleeding and inhibitor formation will require prospective studies. PMID:19563499
Formative Assessment Jump-Starts a Middle Grades Differentiation Initiative
ERIC Educational Resources Information Center
Doubet, Kristina J.
2012-01-01
A rural middle level school had stalled in its third year of a district-wide differentiation initiative. This article describes the way teachers and the leadership team engaged in collaborative practices to put a spotlight on formative assessment. Teachers learned to systematically gather formative assessment data from their students and to use…
Meinen, Amy; Hilgendorf, Amy; Korth, Amy L; Christens, Brian D; Breuer, Catherine; Joyner, Hilary; Polzin, Molle; Adams, Alexandra; Wolfe, Daithi; Braun, Abbe; Hoiting, Jill; Paulson, Jeanette; Cullen, Bridget; Stader, Kelli
2016-11-01
The Wisconsin Early Childhood Obesity Prevention Initiative (Initiative), established in 2007, seeks to address and prevent obesity in the early care and education system through nutrition and physical activity environmental and policy changes. The collaborative includes professionals from 3 state of Wisconsin Departments, the University of Wisconsin-Extension, the University of Wisconsin-Madison, and public health and early care and education organizations. This paper explores the efforts of the Initiative to advance our understanding of collective impact in practice and its value to health promotion efforts. Evaluators conducted a mixed methods case study to evaluate the application of collective impact principles by the Initiative. This included a survey of Initiative partners, review of archival documents, and qualitative interviews with Initiative leaders. Initiative partners noted progress in establishing the conditions for collective impact. Archival documents and interviews describe both formal and informal practices that helped set a common agenda, align and coordinate partner activities, and promote communication among Initiative leaders. Results also detail the important current and potential roles of “backbone” staff from healthTIDE to support the Initiative. Additionally, results suggest particularly challenging aspects of the Initiative’s impact model related to shared measurement and broader stakeholder communication. While the Initiative is still setting in place the conditions for collective impact, it has achieved significant policy, systems, and environment changes since its formation. Inclusion of nutrition and physical activity criteria in the state’s quality rating improvement system for child care centers is one of its outcomes. This case study offers several important insights about the application of collective impact in health promotion efforts, particularly in relation to the transition from previous collaborative activities, the value of establishing a clear common agenda among partners, the roles of backbone staff, and time and partner relationships in collective impact.
Wang, Haode; Ma, Zhoujie; Gai, Xiaotong; Sun, Yanqiu; He, Shidao; Liu, Xian; Wang, Yanfeng; Xuan, Yuanhu
2018-01-01
Rhizoctonia solani AG1 IA is a soil-borne fungal phytopathogen that can significantly harm crops resulting in economic loss. This species overwinters in grass roots and diseased plants, and produces sclerotia that infect future crops. R. solani AG1 IA does not produce spores; therefore, understanding the molecular mechanism of sclerotia formation is important for crop disease control. To identify the genes involved in this process for the development of disease control targets, the transcriptomes of this species were determined at three important developmental stages (mycelium, sclerotial initiation, and sclerotial maturation) using an RNA-sequencing approach. A total of 5,016, 6,433, and 5,004 differentially expressed genes (DEGs) were identified in the sclerotial initiation vs. mycelial, sclerotial maturation vs. mycelial, and sclerotial maturation vs. sclerotial initiation stages, respectively. Moreover, gene ontology (GO) and kyoto encyclopedia of genes and genomes (KEGG) analyses showed that these DEGs were enriched in diverse categories, including oxidoreductase activity, carbohydrate metabolic process, and oxidation-reduction processes. A total of 12 DEGs were further verified using reverse transcription quantitative PCR. Among the genes examined, NADPH oxidase 1 (NOX1) and superoxide dismutase (SOD) were highly induced in the stages of sclerotial initiation and maturation. In addition, the highest reactive oxygen species (ROS) production levels were detected during sclerotial initiation, and enzyme activities of NOX1, SOD, and catalase (CAT) matched with the gene expression profiles. To further evaluate the role of ROS in sclerotial formation, R. solani AG1 IA was treated with the CAT inhibitor aminotriazole and H2O2, resulting in the early differentiation of sclerotia. Taken together, this study provides useful information toward understanding the molecular basis of R. solani AG1 IA sclerotial formation and maturation, and identified the important role of ROS in these processes. PMID:29938140
Production from multiple zones of a tar sands formation
Karanikas, John Michael; Vinegar, Harold J
2013-02-26
A method for treating a tar sands formation includes providing heat to at least part of a hydrocarbon layer in the formation from a plurality of heaters located in the formation. The heat is allowed to transfer from the heaters to at least a portion of the formation. Fluids are produced from the formation through at least one production well that is located in at least two zones in the formation. The first zone has an initial permeability of at least 1 darcy. The second zone has an initial of at most 0.1 darcy. The two zones are separated by a substantially impermeable barrier.
Ueda, Tadaharu; Okumura, Takashi; Tanaka, Yukino; Akase, Saki; Shimamura, Tomoko; Ukeda, Hiroyuki
2016-01-01
A new method was developed to evaluate antioxidant activity based on the redox properties of polyoxometalates, which are partially reduced by antioxidants to generate a limiting potential. The polyoxometalates [PMo12O40](3-), [PVW11O40](4-) and [SV2W10O40]4- formed in situ were used as electrochemical probes for the new evaluation method, and their formation conditions were optimized to evaluate the antioxidant activities of gallic acid, ellagic acid, catechin, quercetin, morin, trans-ferulic acid, sesamol, α-tocopherol, δ-tocopherol and L-ascorbic acid. The observed difference between initial potential and limiting potential (ΔE) were compared with spectrophotometrically evaluated antioxidant activities. In addition, the antioxidant capacities of five beverages (Japanese green tea, concentrated catechin-containing green tea, grapefruit juice, red wine and Japanese sake) were evaluated.
2008-04-01
Initiative acknowledges the dearth of published research on Massively Multiplayer Online Games ((MMOGs), which are based on MMP technology) for...wanting help during the emergency, protesting insufficient aid being delivered in time, escalating to violence , including sniper attacks and attempted... multiplayer environment. The movement control systems were rated "moderately easy" to learn, and ease of movement after learning to use the controls was rated
Improving Joint Function Using Photochemical Hydrogels for Articular Surface Repair
2012-10-01
with thrombin previously has been reported as a favorable scaffold for cartilage formation by encapsulated chondrocytes [10]. Studies over the past...during the photochemical crosslinking process. A full scale study is planned for the first quarter of year 3 to evaluate the fully formed cartilage ...Perform initial study of collagen and PEG gels with stem cells implanted in mice Bone marrow MSCs were harvested from donor swine and grown in culture
Rosenkrantz, Andrew B; Pujara, Akshat C; Taneja, Samir S
2016-05-01
The purpose of this article is to evaluate the utility of a quality improvement (QI) initiative in achieving long-term adherence to an evolving structured format for reporting the level of suspicion for tumor on prostate MRI examinations. The original QI initiative occurred over a 4-month period in 2010, before which prostate MRI was reported using free text. The initiative consisted of development of a section-wide macro, an initial group training session, ordering physician input regarding the structured report's value, subsequent weekly sessions for ongoing review, and timely individualized feedback in instances of nonuse. The initial structured report included pick lists for describing the level of suspicion for tumor as negative, low, medium, or high. Pick lists were modified in 2011 to incorporate a 5-point Likert scale and again in 2015 to incorporate Prostate Imaging Data and Reporting System (PI-RADS) version 2. These refinements were implemented after accelerated training periods. The frequency of reports providing an MRI-based suspicion level during these periods was assessed. Fifty-five percent of reports provided an MRI-based level of suspicion for tumor before the initiative. For various cohorts evaluated after the initiative (using structured reports based on the low, medium, or high scheme; a numeric Likert scale; or PI-RADS), this frequency improved to 95-100% (p < 0.001). Among reports without a suspicion level, potential confounding factors included marked artifact from hip prosthesis and overt diffuse tumor. The QI initiative achieved excellent adherence in reporting a suspicion level for tumor on prostate MRI examinations. The described components of the initiative were useful for maintaining long-term adherence that persisted after serial modifications to the report lexicon.
NASA Technical Reports Server (NTRS)
Noyes, G. P.; Cusick, R. J.
1985-01-01
The three steps in pyrolytic carbon formation are: (1) gaseous hydrocarbon polymerization and aromatic formation; (2) gas-phase condensation and surface adsorption/impingement of polyaromatic hydrocarbon; and (3) final dehydration to carbon. The structure of the carbon in the various stages of formation is examined. The apparatuses and experimental procedures for the pyrolysis of methane in a 60 cm long quartz reactor tube at temperatures ranging from 1400-1600 K are described. The percentage of carbon converted and its density are calculated and tabularly presented. The results reveal that dense carbon formation is maximized and soot eliminated by this procedure. It is observed that conversion efficiency depends on the composition of the inlet gas and conversion increases with increasing temperature. Based on the experimental data a three-man carbon reactor subsystem (CRS) is developed; the functions of the Sabatier Methanation Reactor, two carbon formation reactors and fluid handling components of the CRS are analyzed. The CRS forms 16 kg of carbon at a rate of 0.8 kg/day for 20 days in a two percent volume density quartz wool packing at temperature of 1500-1600 K.
Yoon, Kyoung Ho; Tak, Dae Hyun; Ko, Taeg Su; Park, Sang Eon; Nam, Juhyun; Lee, Sang Hak
2017-03-01
The purpose of this study was to evaluate the prevalence and risk factor of cartilage degeneration of the patellofemoral joint (PFJ) that was diagnosed by second-look arthroscopy. One-hundred and seven patients who underwent ACL reconstruction were evaluated by preoperative MRI, postoperative MRI and second-look arthroscopy. Severity of infrapatellar fat pad (IPFP) fibrosis was evaluated by MRI at an average of 26months after ACL reconstruction. Cartilage degeneration was assessed by second-look arthroscopy at 29months. Twenty-five patients (24.0%) showed cartilage degeneration of the PFJ in second-look arthroscopy. Patients were divided into three groups according to severity of IPFP fibrosis of postoperative MRI (i.e. Group A, focal and incomplete band fibrosis, n=69; Group B, complete band fibrosis, n=31; and Group C, diffuse and infiltrated fibrosis, n=7). Cartilage degeneration of the PFJ was significantly worsened with more fibrosis formation of the IPFP (P<0.001). Other factors for instabilities (BMI, age, concomitant meniscal procedure, time from injury to reconstruction, severity of IPFP fibrosis at preoperative MRI and clinical scores) were not correlated with cartilage degeneration of the PFJ. The multivariate logistic regression analysis of degeneration of the PFJ after ACL reconstruction identified more severe fibrosis tissue formation of the IPFP and initial cartilage defect as significant predictors. More extensive fibrosis of the IPFP and initial cartilage defect may be related to further degenerative changes of the PFJ. Other factors did not affect cartilage degeneration of the PFJ, although the muscle strength, the individual activity level or the rehabilitation protocol was not evaluated in the short-term follow-up period. Copyright © 2016 Elsevier B.V. All rights reserved.
Hibino, Narutoshi; Yi, Tai; Duncan, Daniel R.; Rathore, Animesh; Dean, Ethan; Naito, Yuji; Dardik, Alan; Kyriakides, Themis; Madri, Joseph; Pober, Jordan S.; Shinoka, Toshiharu; Breuer, Christopher K.
2011-01-01
The primary graft-related complication during the first clinical trial evaluating the use of tissue-engineered vascular grafts (TEVGs) was stenosis. We investigated the role of macrophages in the formation of TEVG stenosis in a murine model. We analyzed the natural history of TEVG macrophage infiltration at critical time points and evaluated the role of cell seeding on neovessel formation. To assess the function of infiltrating macrophages, we implanted TEVGs into mice that had been macrophage depleted using clodronate liposomes. To confirm this, we used a CD11b-diphtheria toxin-receptor (DTR) transgenic mouse model. Monocytes infiltrated the scaffold within the first few days and initially transformed into M1 macrophages. As the scaffold degraded, the macrophage infiltrate disappeared. Cell seeding decreased the incidence of stenosis (32% seeded, 64% unseeded, P=0.024) and the degree of macrophage infiltration at 2 wk. Unseeded TEVGs demonstrated conversion from M1 to M2 phenotype, whereas seeded grafts did not. Clodronate and DTR inhibited macrophage infiltration and decreased stenosis but blocked formation of vascular neotissue, evidenced by the absence of endothelial and smooth muscle cells and collagen. These findings suggest that macrophage infiltration is critical for neovessel formation and provides a strategy for predicting, detecting, and inhibiting stenosis in TEVGs.—Hibino, N., Yi, T., Duncan, D. R., Rathore, A., Dean, E., Naito, Y., Dardik, A., Kyriakides, T., Madri, J., Pober, J. S., Shinoka, T., Breuer, C. K. A critical role for macrophages in neovessel formation and the development of stenosis in tissue-engineered vascular grafts. PMID:21865316
Effects of different titanium zirconium implant surfaces on initial supragingival plaque formation.
John, Gordon; Becker, Jürgen; Schwarz, Frank
2017-07-01
The aim of the current study was the evaluation of biofilm development on different implant surfaces. Initial biofilm formation was investigated on five different implant surfaces, machined titanium (MTi), modified machined acid-etched titanium (modMATi), machined titanium zirconium (MTiZr), modified machined and acid-etched titanium zirconium (modMATiZr) and sandblasted large grid and acid-etched titanium zirconium surface (SLATiZr) for 24 and 48 h. Biocompatibility was tested after tooth brushing of the samples via cell viability testing with human gingival fibroblasts. After 24 h of biofilm collection, mean plaque surface was detected in the following descending order: After 24 h: MTiZr > MTi > SLATiZr > modMATiZr > modMATi. Both M surfaces showed significant higher biofilm formation than the other groups. After 48 h: MTiZr > MTi > SLATiZr > modMATiZr > modMATi. After tooth brushing: SLATiZr > modMATi > modMATiZr > MTi > MTiZr. All native samples depicted significant higher cell viability than their corresponding surfaces after biofilm removal procedure. The TiZr groups especially the modMATiZr group showed slower and less biofilm formation. In combination with the good biocompatibility, both modMA surfaces seem to be interesting candidates for surfaces in transgingival implant design. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.
Wood, Brent L; Arroz, Maria; Barnett, David; DiGiuseppe, Joseph; Greig, Bruce; Kussick, Steven J; Oldaker, Teri; Shenkin, Mark; Stone, Elizabeth; Wallace, Paul
2007-01-01
Immunophenotyping by flow cytometry has become standard practice in the evaluation and monitoring of patients with hematopoietic neoplasia. However, despite its widespread use, considerable variability continues to exist in the reagents used for evaluation and the format in which results are reported. As part of the 2006 Bethesda Consensus conference, a committee was formed to attempt to define a consensus set of reagents suitable for general use in the diagnosis and monitoring of hematopoietic neoplasms. The committee included laboratory professionals from private, public, and university hospitals as well as large reference laboratories that routinely operate clinical flow cytometry laboratories with an emphasis on lymphoma and leukemia immunophenotyping. A survey of participants successfully identified the cell lineage(s) to be evaluated for each of a variety of specific medical indications and defined a set of consensus reagents suitable for the initial evaluation of each cell lineage. Elements to be included in the reporting of clinical flow cytometric results for leukemia and lymphoma evaluation were also refined and are comprehensively listed. The 2006 Bethesda Consensus conference represents the first successful attempt to define a set of consensus reagents suitable for the initial evaluation of hematopoietic neoplasia. Copyright 2007 Clinical Cytometry Society.
NASA Astrophysics Data System (ADS)
Zhou, Haiou; Shi, Tiejun; Zhou, Xun
2013-02-01
In this paper, polystyrene (PS)/SiO2 microspheres were successfully prepared via Pickering emulsion polymerization stabilized solely by ethacryloxypropyltrimethoxysilane (MPTMS) modified SiO2 nanoparticles. The formation mechanisms of PS/SiO2 microspheres with different morphology were investigated under various Pickering emulsion polymerization conditions. The results showed that SiO2 concentrations and initiator sorts would synergistically impact on the morphology of products corresponding to distinct formation mechanisms. When SiO2 concentrations was low and water-solute initiator potassium persulfate (KPS) was used, aqueous nucleation was dominant, which was deduced to the formation of dispersive microspheres sparsely anchored by SiO2 particles. When SiO2 concentrations was increased and oil-solute initiator azobisisobutyronitrile (AIBN) was applied, nucleation in oil phase prevailed which lead to the formation of microspheres densely packed by SiO2 particles.
NASA Astrophysics Data System (ADS)
Girina, O.; Fonstein, N.; Yakubovsky, O.; Panahi, D.; Bhattacharya, D.; Jansto, S.
The influence of Nb, Mo, Cr and B on phase transformations and mechanical properties are studied in a 0.15C-2.0Mn-0.3Si-0.020Ti dual phase steel separately and in combination. The formation and decomposition of austenite together with recrystallization of ferrite are evaluated by dilatometry and constructed CCT-diagrams in laboratory processed cold rolled material cooled after full austenitization and from intercritical temperature range. The effect of alloying elements on formation of austenite through their effect on initial hot rolled structure is taken into account. The interpretation of phase transformations during heating and cooling is supported by metallography. The effect of alloying elements on mechanical properties and structure are evaluated by annealing simulations. It has been shown that mechanical properties are strongly influenced by alloying additions such as Nb, Mo, Cr and B through their effect on ferrite formation during continuous cooling and corresponding enrichment of remaining austenite by carbon. Depending on combined effect of these alloying elements, different phase transformations can be promoted during cooling. This allows controlling of final microstructural constituents and mechanical properties.
Method for the measurement of susceptibility to decubitus ulcer formation.
Meijer, J H; Schut, G L; Ribbe, M W; Goovaerts, H G; Nieuwenhuys, R; Reulen, J P; Schneider, H
1989-09-01
A method for measuring the susceptibility of a patient to develop decubitus ulcers is described and initially evaluated. It is based on an indirect, noninvasive measurement of the transient regional blood flow response after a test pressure load which simulates the external stimulus for pressure-sore formation. This method was developed to determine the individual risk of a patient and to study the subfactors which contribute to the susceptibility. This would also offer the possibility of evaluating the effect of preventive treatment aimed at reducing the susceptibility. The method was found to discriminate between preselected elderly patients at risk on the one hand, and non-risk patients and healthy young adults on the other hand. No differences in blood flow responses were found between the non-risk elderly patients and the healthy young adults. This suggests that age per se is not a factor in the formation of pressure sores. In the risk group the recovery time after pressure relief was found to be three times as long as the duration of the pressure exercise. This indicates that the recovery time after pressure exercise may be as important as the period of pressure exercise in deducing the risk of developing decubitus ulcers.
Effects of CO2 laser irradiation on matrix-rich biofilm development formation-an in vitro study.
Zancopé, Bruna Raquel; Dainezi, Vanessa B; Nobre-Dos-Santos, Marinês; Duarte, Sillas; Pardi, Vanessa; Murata, Ramiro M
2016-01-01
A carbon dioxide (CO 2 ) laser has been used to morphologically and chemically modify the dental enamel surface as well as to make it more resistant to demineralization. Despite a variety of experiments demonstrating the inhibitory effect of a CO 2 laser in reduce enamel demineralization, little is known about the effect of surface irradiated on bacterial growth. Thus, this in vitro study was preformed to evaluate the biofilm formation on enamel previously irradiated with a CO 2 laser (λ = 10.6 µM). For this in vitro study, 96 specimens of bovine enamel were employed, which were divided into two groups (n = 48): 1) Control-non-irradiated surface and 2) Irradiated enamel surface. Biofilms were grown on the enamel specimens by one, three and five days under intermittent cariogenic condition in the irradiated and non-irradiated surface. In each assessment time, the biofilm were evaluated by dry weigh, counting the number of viable colonies and, in fifth day, were evaluated by polysaccharides analysis, quantitative real time Polymerase Chain Reaction (PCR) as well as by contact angle. In addition, the morphology of biofilms was characterized by fluorescence microscopy and field emission scanning electron microscopy (FESEM). Initially, the assumptions of equal variances and normal distribution of errors were conferred and the results are analyzed statistically by t-test and Mann Whitney test. The mean of log CFU/mL obtained for the one-day biofilm evaluation showed that there is statistical difference between the experimental groups. When biofilms were exposed to the CO 2 laser, CFU/mL and CFU/dry weight in three day was reduced significantly compared with control group. The difference in the genes expression (Glucosyltransferases (gtfB) and Glucan-binding protein (gbpB)) and polysaccharides was not statically significant. Contact angle was increased relative to control when the surface was irradiated with the CO 2 laser. Similar morphology was also visible with both treatments; however, the irradiated group revealed evidence of melting and fusion in the specimens. In conclusion, CO 2 laser irradiation modifies the energy surface and disrupts the initial biofilm formation.
NASA Astrophysics Data System (ADS)
Yudanto, Sigit Dwi; Imaduddin, Agung; Kurniawan, Budhy; Manaf, Azwar
2018-04-01
Magnesium diboride, MgB2 is a new high critical temperature superconductor that discovered in the beginning of the 21st century. The MgB2 has a simple crystal structure and a high critical temperature, which can be manufactured in several forms like thin films, tapes, wires including bulk in the large scale. For that reason, the MgB2 has good prospects for various applications in the field of electronic devices. In the current work, we have explored the synthesis of MgB2 polycrystalline using powder in a sealed tube method. Different initial boron phase for the synthesized of MgB2 polycrystalline were used. These were, in addition to magnesium powders, crystalline boron, amorphous boron and combination both of them were respectively fitted in the synthesis. The raw materials were mixed in a stoichiometric ratio of Mg: B=1:2, ground using agate mortar, packed into stainless steel SS304. The pack was then sintered at temperature of 800°C for 2 hours in air atmosphere. Phase formation of MgB2 polycrystalline in difference of initial boron phase was characterized using XRD and SEM. Referring to the diffraction pattern and microstructure observation, MgB2 polycrystalline was formed, and the formation was effective when using the crystalline Mg and fully amorphous B as the raw materials. The critical temperature of the specimen was evaluated by the cryogenic magnet. The transition temperature of the MgB2 specimen synthesized using crystalline magnesium and full amorphous boron is 42.678 K (ΔTc = 0.877 K).
Darrington, Richard T; Jiao, Jim
2004-04-01
Rapid and accurate stability prediction is essential to pharmaceutical formulation development. Commonly used stability prediction methods include monitoring parent drug loss at intended storage conditions or initial rate determination of degradants under accelerated conditions. Monitoring parent drug loss at the intended storage condition does not provide a rapid and accurate stability assessment because often <0.5% drug loss is all that can be observed in a realistic time frame, while the accelerated initial rate method in conjunction with extrapolation of rate constants using the Arrhenius or Eyring equations often introduces large errors in shelf-life prediction. In this study, the shelf life prediction of a model pharmaceutical preparation utilizing sensitive high-performance liquid chromatography-mass spectrometry (LC/MS) to directly quantitate degradant formation rates at the intended storage condition is proposed. This method was compared to traditional shelf life prediction approaches in terms of time required to predict shelf life and associated error in shelf life estimation. Results demonstrated that the proposed LC/MS method using initial rates analysis provided significantly improved confidence intervals for the predicted shelf life and required less overall time and effort to obtain the stability estimation compared to the other methods evaluated. Copyright 2004 Wiley-Liss, Inc. and the American Pharmacists Association.
Harte, Philip T.
2017-01-01
A common assumption with groundwater sampling is that low (<0.5 L/min) pumping rates during well purging and sampling captures primarily lateral flow from the formation through the well-screened interval at a depth coincident with the pump intake. However, if the intake is adjacent to a low hydraulic conductivity part of the screened formation, this scenario will induce vertical groundwater flow to the pump intake from parts of the screened interval with high hydraulic conductivity. Because less formation water will initially be captured during pumping, a substantial volume of water already in the well (preexisting screen water or screen storage) will be captured during this initial time until inflow from the high hydraulic conductivity part of the screened formation can travel vertically in the well to the pump intake. Therefore, the length of the time needed for adequate purging prior to sample collection (called optimal purge duration) is controlled by the in-well, vertical travel times. A preliminary, simple analytical model was used to provide information on the relation between purge duration and capture of formation water for different gross levels of heterogeneity (contrast between low and high hydraulic conductivity layers). The model was then used to compare these time–volume relations to purge data (pumping rates and drawdown) collected at several representative monitoring wells from multiple sites. Results showed that computation of time-dependent capture of formation water (as opposed to capture of preexisting screen water), which were based on vertical travel times in the well, compares favorably with the time required to achieve field parameter stabilization. If field parameter stabilization is an indicator of arrival time of formation water, which has been postulated, then in-well, vertical flow may be an important factor at wells where low-flow sampling is the sample method of choice.
Sorensen, Mathew D; Hsi, Ryan S; Chi, Thomas; Shara, Nawar; Wactawski-Wende, Jean; Kahn, Arnold J; Wang, Hong; Hou, Lifang; Stoller, Marshall L
2014-12-01
We evaluated the relationship between dietary fiber, fruit and vegetable intake, and the risk of kidney stone formation. Overall 83,922 postmenopausal women from the Women's Health Initiative observational study were included in the analysis and followed prospectively. Cox proportional hazards regression analyses were used to evaluate the associations between total dietary fiber, fruit and vegetable intake, and the risk of incident kidney stone formation, adjusting for nephrolithiasis risk factors (age, race/ethnicity, geographic region, diabetes mellitus, calcium supplementation, hormone therapy use, body mass index and calibrated caloric intake; and dietary water, sodium, animal protein and calcium intake). Women with a history of kidney stones (3,471) were analyzed separately. Mean age of the women was 64±7 years, 85% were white and 2,937 (3.5%) experienced a kidney stone in a median followup of 8 years. In women with no history of kidney stones higher total dietary fiber (6% to 26% decreased risk, p <0.001), greater fruit intake (12% to 25% decreased risk, p <0.001) and greater vegetable intake (9% to 22% decreased risk, p=0.002) were associated with a decreased risk of incident kidney stone formation in separate adjusted models. In women with a history of stones there were no significant protective effects of fiber, fruit or vegetable intake on the risk of kidney stone recurrence. Greater dietary intake of fiber, fruits and vegetables was associated with a reduced risk of incident kidney stones in postmenopausal women. The protective effects were independent of other known risk factors for kidney stones. In contrast, there was no reduction in risk in women with a history of stones. Copyright © 2014 American Urological Association Education and Research, Inc. Published by Elsevier Inc. All rights reserved.
Evaluation of pyrolysis and arc tracking on candidate wire insulation designs for space applications
NASA Technical Reports Server (NTRS)
Stueber, Thomas J.; Hrovat, Kenneth
1994-01-01
The ability of wire insulation materials and constructions to resist arc tracking was determined and the damage caused by initial arcing and restrike events was assessed. Results of arc tracking tests on various insulation constructions are presented in view-graph format. Arc tracking tests conducted on Champlain, Filotex, and Teledyne Thermatics indicate the Filotex is least likely to arc track. Arc tracking occurs more readily in air than it does in vacuum.
Journal of Special Operations Medicine. Volume 4, Edition 1, Winter 2004
2004-01-01
an ophthalmologist. He has been instrumental in PRK initiatives, has been a very productive mem- ber of the BISC, knows the risks of our missions...results to SOF mission commanders in a format suit- able for training at the unit level. 1999-3 PROSPECTIVE EVALUATION OF WAVE- FRONT-GUIDED PRK (Year...1 of 3) Conduct a prospective, randomized clinical trial to compare PRK for the treatment of naturally occurring myopia and astigmatism using
ERIC Educational Resources Information Center
Cummings, Kelli D.; Stoolmiller, Michael L.; Baker, Scott K.; Fien, Hank; Kame'enui, Edward J.
2015-01-01
We present a method for data-based decision making at the school level using student achievement data. We demonstrate the potential of a national assessment database [i.e., the University of Oregon DIBELS Data System (DDS)] to provide comparative levels of school-level data on average student achievement gains. Through the DDS as a data source,…
DOE Office of Scientific and Technical Information (OSTI.GOV)
Matsumoto, Yuji; Kokubo, Eiichiro, E-mail: ymatsumoto@cfca.nao.ac.jp
Recent observations have revealed the eccentricity and inclination distributions of close-in super-Earths. These distributions have the potential to constrain their formation processes. In the in situ formation scenario, the eccentricities and inclinations of planets are determined by gravitational scattering and collisions between protoplanets on the giant impact stage. We investigate the effect of the initial eccentricities and inclinations of protoplanets on the formation of close-in super-Earths. We perform N -body simulations of protoplanets in gas-free disks, changing the initial eccentricities and inclinations systematically. We find that while the eccentricities of protoplanets are well relaxed through their evolution, the inclinations aremore » not. When the initial inclinations are small, they are not generally pumped up since scattering is less effective and collisions occur immediately after orbital crossing. On the other hand, when the initial inclinations are large, they tend to be kept large since collisional damping is less effective. Not only the resultant inclinations of planets, but also their number, eccentricities, angular momentum deficit, and orbital separations are affected by the initial inclinations of protoplanets.« less
Atala, E; Velásquez, G; Vergara, C; Mardones, C; Reyes, J; Tapia, R A; Quina, F; Mendes, M A; Speisky, H; Lissi, E; Ureta-Zañartu, M S; Aspée, A; López-Alarcón, C
2013-05-02
Pyrogallol red (PGR) presents high reactivity toward reactive (radical and nonradical) species (RS). This property of PGR, together with its characteristic spectroscopic absorption in the visible region, has allowed developing methodologies aimed at evaluating the antioxidant capacity of foods, beverages, and human fluids. These methods are based on the evaluation of the consumption of PGR induced by RS and its inhibition by antioxidants. However, at present, there are no reports regarding the degradation mechanism of PGR, limiting the extrapolation to how antioxidants behave in different systems comprising different RS. In the present study, we evaluate the kinetics of PGR consumption promoted by different RS (peroxyl radicals, peroxynitrite, nitrogen dioxide, and hypochlorite) using spectroscopic techniques and detection of product by HPLC mass spectrometry. The same pattern of oxidation and spectroscopic properties of the products is observed, independently of the RS employed. Mass analysis indicates the formation of only one product identified as a quinone derivative, excluding the formation of peroxides or hydroperoxides and/or chlorinated compounds, in agreement with FOX's assays and oxygen consumption experiments. Cyclic voltammetry, carried out at different pH's, shows an irreversible oxidation of PGR, indicating the initial formation of a phenoxy radical and a second charge transfer reaction generating an ortho-quinone derivative. Spectroelectrochemical oxidation of PGR shows oxidation products with identical UV-visible absorption properties to those observed in RS-induced oxidation.
Nam, Ki Min; Choi, Young Cheol; Jung, Sung Chul; Kim, Yong-Il; Jo, Mi Ru; Park, Se Ho; Kang, Yong-Mook; Han, Young-Kyu; Park, Joon T
2012-01-21
Thermal decomposition of Co(acac)(3) and Cu(acac)(2) in benzylamine leads to the formation of [100] directed Cu-doped h-CoO nanorods, which are very stable in an aqueous solution. The formation mechanism of the [100] directed Cu-doped h-CoO nanorods is fully elucidated by using first-principles calculations, demonstrating that Cu-doping not only changes the growth direction but also enhances the stability of the nanorods significantly. Evaluation of the electrochemical performance of Cu-doped h-CoO nanorods shows high initial Coulombic efficiency and ultrahigh capacity with excellent cycling performance, indicating their suitability as an anode material for next generation lithium-ion batteries.
Pereira, D; Gomes, P; Faria, S; Cruz-Correia, R; Coimbra, M
2016-08-01
Auscultation is currently both a powerful screening tool, providing a cheap and quick initial assessment of a patient's clinical condition, and a hard skill to master. The teaching of auscultation in Universities is today reduced to an unsuitable number of hours. Virtual patient simulators can potentially mitigate this problem, by providing an interesting high-quality alternative to teaching with real patients or patient simulators. In this paper we evaluate the pedagogical impact of using a virtual patient simulation technology in a short workshop format for medical students, training them to detect cardiac pathologies. Results showed a significant improvement (+16%) in the differentiation between normal and pathological cases, although longer duration formats seem to be needed to accurately identify specific pathologies.
NASA Technical Reports Server (NTRS)
Fisher, John; Wignarajah, K.; Howard, Kevin; Serio, Mike; Kroo, Eric
2004-01-01
The prototype dry pyrolyser delivered to Ames Research Center is the end-product of a Phase I1 Small Business Initiative Research (SBIR) project. Some of the major advantages of pyrolysis for processing solid wastes are that it can process solid wastes, it permits elemental recycling while conserving oxygen use, and it can function as a pretreatment for combustion processes. One of the disadvantages of pyrolysis is the formation of tars. By controlling the rate of heating, tar formation can be minimized. This paper presents data on the pyrolysis of various space station wastes. The performance of the pyrolyser is also discussed and appropriate modifications suggested to improve the performance of the dry pyrolyzer.
Real-time near IR (1310 nm) imaging of CO2 laser ablation of enamel.
Darling, Cynthia L; Fried, Daniel
2008-02-18
The high-transparency of dental enamel in the near-IR (NIR) can be exploited for real-time imaging of ablation crater formation during drilling with lasers. NIR images were acquired with an InGaAs focal plane array and a NIR zoom microscope during drilling incisions in human enamel samples with a lambda=9.3-microm CO(2) laser operating at repetition rates of 50-300-Hz with and without a water spray. Crack formation, dehydration and thermal changes were observed during ablation. These initial images demonstrate the potential of NIR imaging to monitor laser-ablation events in real-time to provide information about the mechanism of ablation and to evaluate the potential for peripheral thermal and mechanical damage.
NASA Astrophysics Data System (ADS)
Florschutz, Anthony Vatroslav
Utilization of bone grafts for the treatment of skeletal pathology is a common practice in orthopaedic, craniomaxillofacial, dental, and plastic surgery. Autogenous bone graft is the established archetype but has disadvantages including donor site morbidity, limited supply, and prolonging operative time. In order to avoid these and other issues, bone graft substitute materials are becoming increasingly prevalent among surgeons for reconstructing skeletal defects and arthrodesis applications. Bone graft substitutes are biomaterials, biologics, and guided tissue/bone regenerative devices that can be used alone or in combinations as supplements or alternatives to autogenous bone graft. There is a growing interest and trend to specialize graft substitutes for specific indications and although there is good rationale for this indication-specific approach, the development and utility of a more universal bone graft substitute may provide a better answer for patients and surgeons. The aim of the present research focuses on the design, synthesis, and initial evaluation of D-glyceraldehyde crosslinked gelatin-hydroxyapatite composites for potential use as a bone graft substitutes. After initial establishment of rational material design, gelatinhydroxyapatite scaffolds were fabricated with different gelatin:hydroxyapatite ratios and crosslinking concentrations. The synthesized scaffolds were subsequently evaluated on the basis of their swelling behavior, porosity, density, percent composition, mechanical properties, and morphology and further assessed with respect to cell-biomaterial interaction and biomineralization in vitro. Although none of the materials achieved mechanical properties suitable for structural graft applications, a reproducible material design and synthesis was achieved with properties recognized to facilitate bone formation. Select scaffold formulations as well as a subset of scaffolds loaded with recombinant human bone morphogenetic protein-2 were implanted ectopically in a rodent animal model and histologically evaluated for biocompatibility, degradation, and bone formation in vivo. The gelatin-hydroxyapatite scaffolds retained dimensional structure over 28 days and did not elicit any undesirable systemic or local effects. Distinct areas of mineralization and osteoid/bone were noted in all the implanted scaffolds and quantitative differences were primarily dependent on the presence of hydroxyapatite.
Multi-Objective Online Initialization of Spacecraft Formations
NASA Technical Reports Server (NTRS)
Jeffrey, Matthew; Breger, Louis; How, Jonathan P.
2007-01-01
This paper extends a previously developed method for finding spacecraft initial conditions (ICs) that minimize the drift resulting from J2 disturbances while also minimizing the fuel required to attain those ICs. It generalizes the single spacecraft optimization to a formation-wide optimization valid for an arbitrary number of vehicles. Additionally, the desired locations of the spacecraft, separate from the starting location, can be specified, either with respect to a reference orbit, or relative to the other spacecraft in the formation. The three objectives (minimize drift, minimize fuel, and maintain a geometric template) are expressed as competing costs in a linear optimization, and are traded against one another through the use of scalar weights. By carefully selecting these weights and re-initializing the formation at regular intervals, a closed-loop, formation-wide control system is created. This control system can be used to reconfigure the formations on the fly, and creates fuel-efficient plans by placing the spacecraft in semi-invariant orbits. The overall approach is demonstrated through nonlinear simulations for two formations a GEO orbit, and an elliptical orbit.
Yan, Li; Ye, Jie; Zhang, Panyue; Xu, Dong; Wu, Yan; Liu, Jianbo; Zhang, Haibo; Fang, Wei; Wang, Bei; Zeng, Guangming
2018-07-01
High sulfur content in excess sludge impacts the production of biomethane during anaerobic digestion, meanwhile leads to hydrogen sulfide (H 2 S) formation in biogas. Effect of initial sludge pH on H 2 S formation during batch mesophilic anaerobic digestion of slaughterhouse wastewater sludge was studied in this paper. The results demonstrated that when the initial sludge pH increased from 6.5 to 8.0, the biogas production increased by 10.1%, the methane production increased by 64.1%, while the H 2 S content in biogas decreased by 44.7%. The higher initial sludge pH inhibited the competition of sulfate-reducing bacteria with methane-producing bacteria, and thus benefitted the growth of methanogens. Positive correlation was found between the relative abundance of Desulfomicrobium and H 2 S production, as well as the relative abundance of Methanosarcina and methane production. More sulfates and organic sulfur were transferred to solid and liquid rather than H 2 S formation at a high initial pH. Copyright © 2018 Elsevier Ltd. All rights reserved.
van de Kruijs, Bastiaan H P; Dressen, Mark H C L; Meuldijk, Jan; Vekemans, Jef A J M; Hulshof, Lumbertus A
2010-04-07
A detailed study regarding the influence of microwave irradiation on the formation of a series of Grignard reagents in terms of rates and selectivities has revealed that these heterogeneous reactions may display a beneficial microwave effect. The interaction between microwaves and magnesium turnings generates violent electrostatic discharges. These discharges on magnesium lead to melting of the magnesium surface, thus generating highly active magnesium particles. As compared to conventional operation the microwave-induced discharges on the magnesium surface lead to considerably shorter initiation times for the insertion of magnesium in selected substrates (i.e. halothiophenes, halopyridines, octyl halides, and halobenzenes). Thermographic imaging and surface characterization by scanning electron microscopy showed that neither selective heating nor a "specific" microwave effect was causing the reduction in initiation times. This novel and straightforward initiation method eliminates the use of toxic and environmentally adverse initiators. Thus, this initiation method limits the formation of by-products. We clearly demonstrated that microwave irradiation enables fast Grignard reagent formation. Therefore, microwave technology is promising for process intensification of Grignard based coupling reactions.
NASA Technical Reports Server (NTRS)
Kingsmill, David E.; Yuter, Sandra E.; Hobbs, Peter V.; Rangno, Arthur L.; Heymsfield, Andrew J.; Stith, Jeffrey L.; Bansemer, Aaron; Haggerty, Julie A.; Korolev, Alexei V.
2004-01-01
A customized product for analysis of microphysics data collected from aircraft during field campaigns in support of the TRMM program is described. These Common Microphysics Products (CMP's) are designed to aid in evaluation of TRMM spaceborne precipitation retrieval algorithms. Information needed for this purpose (e.g., particle size spectra and habit, liquid and ice water content) was derived using a common processing strategy on the wide variety of microphysical instruments and raw native data formats employed in the field campaigns. The CMP's are organized into an ASCII structure to allow easy access to the data for those less familiar with and without the tools to accomplish microphysical data processing. Detailed examples of the CMP show its potential and some of its limitations. This approach may be a first step toward developing a generalized microphysics format and an associated community-oriented, non-proprietary software package for microphysics data processing, initiatives that would likely broaden community access to and use of microphysics datasets.
NASA Astrophysics Data System (ADS)
Fan, Yang; Qi, Yang; Bing, Gao; Rong, Xia; Yanjie, Le; Iroegbu, Paul Ikechukwu
2018-03-01
Water tree is the predominant defect in high-voltage crosslinked polyethylene cables. The microscopic mechanism in the discharge process is not fully understood; hence, a drawback is created towards an effective method to evaluate the insulation status. In order to investigate the growth of water tree, a plasma-chemical model is developed. The dynamic characteristics of the discharge process including voltage waveform, current waveform, electron density, electric potential, and electric field intensity are analyzed. Our results show that the distorted electric field is the predominant contributing factor of electron avalanche formation, which inevitably leads to the formation of pulse current. In addition, it is found that characteristic parameters such as the pulse width and pulse number have a great relevance to the length of water tree. Accordingly, the growth of water tree can be divided into the initial stage, development stage, and pre-breakdown stage, which provides a reference for evaluating the deteriorated stages of crosslinked polyethylene cables.
ERIC Educational Resources Information Center
Hamodi, Carolina; López-Pastor, Víctor Manuel; López-Pastor, Ana Teresa
2017-01-01
The aim of this article is to analyse whether having experience of formative assessment during their initial teacher education courses (ITE) influences graduates' subsequent practice as teachers. That is, if the assessment methods that university students are subject to during their learning process are then actually employed by them during their…
NASA Astrophysics Data System (ADS)
Avdeev, A. V.; Boreisho, A. S.; Ivakin, S. V.; Moiseev, A. A.; Savin, A. V.; Sokolov, E. I.; Smirnov, P. G.
2018-01-01
This article is devoted to the simulation of the processes of formation of dust clouds in the absence of gravitation, which is necessary for understanding the processes proceeding in dust clusters in outer space, upper planetary atmosphere, and on the surface of space objects, as well as for evaluating the possibilities of creating disperse structures with given properties. The chief aim of the simulation is to determine the general laws of the dynamics of the dust cloud at the initial stage of its formation. With the use of the original approach based on the particle-in-cell method that permits investigating the mechanics of large ensembles of particles on contemporary computational platforms, we consider the mechanics of a dusty medium in the process of its excitation in a closed container due to the vibration of the walls, and then in the process of particle scattering when the container opens in outer space. The main formation mechanisms of a dust formation have been elucidated, and the possibilities of mathematical simulation for predicting spatial and time characteristics of disperse structures have been shown.
GVE-Based Dynamics and Control for Formation Flying Spacecraft
NASA Technical Reports Server (NTRS)
Breger, Louis; How, Jonathan P.
2004-01-01
Formation flying is an enabling technology for many future space missions. This paper presents extensions to the equations of relative motion expressed in Keplerian orbital elements, including new initialization techniques for general formation configurations. A new linear time-varying form of the equations of relative motion is developed from Gauss Variational Equations and used in a model predictive controller. The linearizing assumptions for these equations are shown to be consistent with typical formation flying scenarios. Several linear, convex initialization techniques are presented, as well as a general, decentralized method for coordinating a tetrahedral formation using differential orbital elements. Control methods are validated using a commercial numerical propagator.
A tungsten-rhenium interatomic potential for point defect studies
Setyawan, Wahyu; Gao, Ning; Kurtz, Richard J.
2018-05-28
A tungsten-rhenium (W-Re) classical interatomic potential is developed within the embedded atom method (EAM) interaction framework. A force-matching method is employed to fit the potential to ab initio forces, energies, and stresses. Simulated annealing is combined with the conjugate gradient technique to search for an optimum potential from over 1000 initial trial sets. The potential is designed for studying point defects in W-Re systems. It gives good predictions of the formation energies of Re defects in W and the binding energies of W self-interstitial clusters with Re. The potential is further evaluated for describing the formation energy of structures inmore » the σ and χ intermetallic phases. The predicted convex-hulls of formation energy are in excellent agreement with ab initio data. In pure Re, the potential can reproduce the formation energies of vacancy and self-interstitial defects sufficiently accurately, and gives the correct ground state self-interstitial configuration. Furthermore, by including liquid structures in the fit, the potential yields a Re melting temperature (3130 K) that is close to the experimental value (3459 K).« less
A tungsten-rhenium interatomic potential for point defect studies
NASA Astrophysics Data System (ADS)
Setyawan, Wahyu; Gao, Ning; Kurtz, Richard J.
2018-05-01
A tungsten-rhenium (W-Re) classical interatomic potential is developed within the embedded atom method interaction framework. A force-matching method is employed to fit the potential to ab initio forces, energies, and stresses. Simulated annealing is combined with the conjugate gradient technique to search for an optimum potential from over 1000 initial trial sets. The potential is designed for studying point defects in W-Re systems. It gives good predictions of the formation energies of Re defects in W and the binding energies of W self-interstitial clusters with Re. The potential is further evaluated for describing the formation energy of structures in the σ and χ intermetallic phases. The predicted convex-hulls of formation energy are in excellent agreement with ab initio data. In pure Re, the potential can reproduce the formation energies of vacancies and self-interstitial defects sufficiently accurately and gives the correct ground state self-interstitial configuration. Furthermore, by including liquid structures in the fit, the potential yields a Re melting temperature (3130 K) that is close to the experimental value (3459 K).
A tungsten-rhenium interatomic potential for point defect studies
DOE Office of Scientific and Technical Information (OSTI.GOV)
Setyawan, Wahyu; Gao, Ning; Kurtz, Richard J.
A tungsten-rhenium (W-Re) classical interatomic potential is developed within the embedded atom method (EAM) interaction framework. A force-matching method is employed to fit the potential to ab initio forces, energies, and stresses. Simulated annealing is combined with the conjugate gradient technique to search for an optimum potential from over 1000 initial trial sets. The potential is designed for studying point defects in W-Re systems. It gives good predictions of the formation energies of Re defects in W and the binding energies of W self-interstitial clusters with Re. The potential is further evaluated for describing the formation energy of structures inmore » the σ and χ intermetallic phases. The predicted convex-hulls of formation energy are in excellent agreement with ab initio data. In pure Re, the potential can reproduce the formation energies of vacancy and self-interstitial defects sufficiently accurately, and gives the correct ground state self-interstitial configuration. Furthermore, by including liquid structures in the fit, the potential yields a Re melting temperature (3130 K) that is close to the experimental value (3459 K).« less
Semianalytical solutions for transport in aquifer and fractured clay matrix system
NASA Astrophysics Data System (ADS)
Huang, Junqi; Goltz, Mark N.
2015-09-01
A three-dimensional mathematical model that describes transport of contaminant in a horizontal aquifer with simultaneous diffusion into a fractured clay formation is proposed. A group of semianalytical solutions is derived based on specific initial and boundary conditions as well as various source functions. The analytical model solutions are evaluated by numerical Laplace inverse transformation and analytical Fourier inverse transformation. The model solutions can be used to study the fate and transport in a three-dimensional spatial domain in which a nonaqueous phase liquid exists as a pool atop a fractured low-permeability clay layer. The nonaqueous phase liquid gradually dissolves into the groundwater flowing past the pool, while simultaneously diffusing into the fractured clay formation below the aquifer. Mass transfer of the contaminant into the clay formation is demonstrated to be significantly enhanced by the existence of the fractures, even though the volume of fractures is relatively small compared to the volume of the clay matrix. The model solution is a useful tool in assessing contaminant attenuation processes in a confined aquifer underlain by a fractured clay formation.
NASA Astrophysics Data System (ADS)
Sleiman, Mohamad; Destaillats, Hugo; Smith, Jared D.; Liu, Chen-Lin; Ahmed, Musahid; Wilson, Kevin R.; Gundel, Lara A.
2010-11-01
We used controlled laboratory experiments to evaluate the aerosol-forming potential of ozone reactions with nicotine and secondhand smoke. Special attention was devoted to real-time monitoring of the particle size distribution and chemical composition of SOA as they are believed to be key factors determining the toxicity of SOA. The experimental approach was based on using a vacuum ultraviolet photon ionization time-of-flight aerosol mass spectrometer (VUV-AMS), a scanning mobility particle sizer (SMPS) and off-line thermal desorption coupled to mass spectrometry (TD-GC-MS) for gas-phase byproducts analysis. Results showed that exposure of SHS to ozone induced the formation of ultrafine particles (<100 nm) that contained high molecular weight nitrogenated species ( m/ z 400-500), which can be due to accretion/acid-base reactions and formation of oligomers. In addition, nicotine was found to contribute significantly (with yields 4-9%) to the formation of secondary organic aerosol through reaction with ozone. The main constituents of the resulting SOA were tentatively identified and a reaction mechanism was proposed to elucidate their formation. These findings identify a new component of thirdhand smoke that is associated with the formation of ultrafine particles (UFP) through oxidative aging of secondhand smoke. The significance of this chemistry for indoor exposure and health effects is highlighted.
Sugar fatty acid esters inhibit biofilm formation by food-borne pathogenic bacteria
Furukawa, Soichi; Akiyoshi, Yuko; O’Toole, George A.; Ogihara, Hirokazu; Morinaga, Yasushi
2010-01-01
Effects of food additives on biofilm formation by food-borne pathogenic bacteria were investigated. Thirty-three potential food additives and 3 related compounds were added to the culture medium at concentrations from 0.001 to 0.1% (w/w), followed by inoculation and cultivation of five biofilm-forming bacterial strains for the evaluation of biofilm formation. Among the tested food additives, 21 showed inhibitory effects of biofilm formation by Staphylococcus aureus and Escherichia coli, and in particular, sugar fatty acid esters showed significant anti-biofilm activity. Sugar fatty acid esters with long chain fatty acid residues (C14-16) exerted their inhibitory effect at the concentration of 0.001%(w/w), but bacterial growth was not affected at this low concentration. Activities of the sugar fatty acid esters positively correlated with the increase of the chain length of the fatty acid residues. Sugar fatty acid esters inhibited the initial attachment of the Staphylococcus aureus cells to the abiotic surface. Sugar fatty acid esters with long chain fatty acid residues (C14-16) also inhibited biofilm formation by Streptococcus mutans and Listeria monocytogenes at 0.01%(w/w), while the inhibition of biofilm formation by Pseudomonas aeruginosa required the addition of a far higher concentration (0.1%(w/w)) of the sugar fatty acid esters. PMID:20089325
Stellar populations dominated by massive stars in dusty starburst galaxies across cosmic time
NASA Astrophysics Data System (ADS)
Zhang, Zhi-Yu; Romano, D.; Ivison, R. J.; Papadopoulos, Padelis P.; Matteucci, F.
2018-06-01
All measurements of cosmic star formation must assume an initial distribution of stellar masses—the stellar initial mass function—in order to extrapolate from the star-formation rate measured for typically rare, massive stars (of more than eight solar masses) to the total star-formation rate across the full stellar mass spectrum1. The shape of the stellar initial mass function in various galaxy populations underpins our understanding of the formation and evolution of galaxies across cosmic time2. Classical determinations of the stellar initial mass function in local galaxies are traditionally made at ultraviolet, optical and near-infrared wavelengths, which cannot be probed in dust-obscured galaxies2,3, especially distant starbursts, whose apparent star-formation rates are hundreds to thousands of times higher than in the Milky Way, selected at submillimetre (rest-frame far-infrared) wavelengths4,5. The 13C/18O isotope abundance ratio in the cold molecular gas—which can be probed via the rotational transitions of the 13CO and C18O isotopologues—is a very sensitive index of the stellar initial mass function, with its determination immune to the pernicious effects of dust. Here we report observations of 13CO and C18O emission for a sample of four dust-enshrouded starbursts at redshifts of approximately two to three, and find unambiguous evidence for a top-heavy stellar initial mass function in all of them. A low 13CO/C18O ratio for all our targets—alongside a well tested, detailed chemical evolution model benchmarked on the Milky Way6—implies that there are considerably more massive stars in starburst events than in ordinary star-forming spiral galaxies. This can bring these extraordinary starbursts closer to the `main sequence' of star-forming galaxies7, although such main-sequence galaxies may not be immune to changes in initial stellar mass function, depending on their star-formation densities.
Stellar populations dominated by massive stars in dusty starburst galaxies across cosmic time.
Zhang, Zhi-Yu; Romano, D; Ivison, R J; Papadopoulos, Padelis P; Matteucci, F
2018-06-01
All measurements of cosmic star formation must assume an initial distribution of stellar masses-the stellar initial mass function-in order to extrapolate from the star-formation rate measured for typically rare, massive stars (of more than eight solar masses) to the total star-formation rate across the full stellar mass spectrum 1 . The shape of the stellar initial mass function in various galaxy populations underpins our understanding of the formation and evolution of galaxies across cosmic time 2 . Classical determinations of the stellar initial mass function in local galaxies are traditionally made at ultraviolet, optical and near-infrared wavelengths, which cannot be probed in dust-obscured galaxies 2,3 , especially distant starbursts, whose apparent star-formation rates are hundreds to thousands of times higher than in the Milky Way, selected at submillimetre (rest-frame far-infrared) wavelengths 4,5 . The 13 C/ 18 O isotope abundance ratio in the cold molecular gas-which can be probed via the rotational transitions of the 13 CO and C 18 O isotopologues-is a very sensitive index of the stellar initial mass function, with its determination immune to the pernicious effects of dust. Here we report observations of 13 CO and C 18 O emission for a sample of four dust-enshrouded starbursts at redshifts of approximately two to three, and find unambiguous evidence for a top-heavy stellar initial mass function in all of them. A low 13 CO/C 18 O ratio for all our targets-alongside a well tested, detailed chemical evolution model benchmarked on the Milky Way 6 -implies that there are considerably more massive stars in starburst events than in ordinary star-forming spiral galaxies. This can bring these extraordinary starbursts closer to the 'main sequence' of star-forming galaxies 7 , although such main-sequence galaxies may not be immune to changes in initial stellar mass function, depending on their star-formation densities.
Appropriate Statistics for Determining Chance-Removed Interpractitioner Agreement.
Popplewell, Michael; Reizes, John; Zaslawski, Chris
2018-05-31
Fleiss' Kappa (FK) has been commonly, but incorrectly, employed as the "standard" for evaluating chance-removed inter-rater agreement with ordinal data. This practice may lead to misleading conclusions in inter-rater agreement research. An example is presented that demonstrates the conditions where FK produces inappropriate results, compared with Gwet's AC2, which is proposed as a more appropriate statistic. A novel format for recording a Chinese Medical (CM) diagnoses, called the Diagnostic System of Oriental Medicine (DSOM), was used to record and compare patient diagnostic data, which, unlike the contemporary CM diagnostic format, allows agreement by chance to be considered when evaluating patient data obtained with unrestricted diagnostic options available to diagnosticians. Five CM practitioners diagnosed 42 subjects drawn from an open population. Subjects' diagnoses were recorded using the DSOM format. All the available data were initially used to evaluate agreement. Then, the subjects were sorted into three groups to demonstrate the effects of differing data marginality on the calculated chance-removed agreement. Agreement between the practitioners for each subject was evaluated with linearly weighted simple agreement, FK and Gwet's AC2. In all cases, overall agreement was much lower with FK than Gwet's AC2. Larger differences occurred when the data were more free marginal. Inter-rater agreement determined with FK statistics is unlikely to be correct unless it can be shown that the data from which agreement is determined are, in fact, fixed marginal. It follows that results obtained on agreement between practitioners with FK are probably incorrect. It is shown that inter-rater agreement evaluated with AC2 statistic is an appropriate measure when fixed marginal data are neither expected nor guaranteed. The AC2 statistic should be used as the standard statistical approach for determining agreement between practitioners.
Laser Ignition Technology for Bi-Propellant Rocket Engine Applications
NASA Technical Reports Server (NTRS)
Thomas, Matthew E.; Bossard, John A.; Early, Jim; Trinh, Huu; Dennis, Jay; Turner, James (Technical Monitor)
2001-01-01
The fiber optically coupled laser ignition approach summarized is under consideration for use in igniting bi-propellant rocket thrust chambers. This laser ignition approach is based on a novel dual pulse format capable of effectively increasing laser generated plasma life times up to 1000 % over conventional laser ignition methods. In the dual-pulse format tinder consideration here an initial laser pulse is used to generate a small plasma kernel. A second laser pulse that effectively irradiates the plasma kernel follows this pulse. Energy transfer into the kernel is much more efficient because of its absorption characteristics thereby allowing the kernel to develop into a much more effective ignition source for subsequent combustion processes. In this research effort both single and dual-pulse formats were evaluated in a small testbed rocket thrust chamber. The rocket chamber was designed to evaluate several bipropellant combinations. Optical access to the chamber was provided through small sapphire windows. Test results from gaseous oxygen (GOx) and RP-1 propellants are presented here. Several variables were evaluated during the test program, including spark location, pulse timing, and relative pulse energy. These variables were evaluated in an effort to identify the conditions in which laser ignition of bi-propellants is feasible. Preliminary results and analysis indicate that this laser ignition approach may provide superior ignition performance relative to squib and torch igniters, while simultaneously eliminating some of the logistical issues associated with these systems. Further research focused on enhancing the system robustness, multiplexing, and window durability/cleaning and fiber optic enhancements is in progress.
Numerical Modelling of Extended Leak-Off Test with a Pre-Existing Fracture
NASA Astrophysics Data System (ADS)
Lavrov, A.; Larsen, I.; Bauer, A.
2016-04-01
Extended leak-off test (XLOT) is one of the few techniques available for stress measurements in oil and gas wells. Interpretation of the test is often difficult since the results depend on a multitude of factors, including the presence of natural or drilling-induced fractures in the near-well area. Coupled numerical modelling of XLOT has been performed to investigate the pressure behaviour during the flowback phase as well as the effect of a pre-existing fracture on the test results in a low-permeability formation. Essential features of XLOT known from field measurements are captured by the model, including the saw-tooth shape of the pressure vs injected volume curve, and the change of slope in the pressure vs time curve during flowback used by operators as an indicator of the bottomhole pressure reaching the minimum in situ stress. Simulations with a pre-existing fracture running from the borehole wall in the radial direction have revealed that the results of XLOT are quite sensitive to the orientation of the pre-existing fracture. In particular, the fracture initiation pressure and the formation breakdown pressure increase steadily with decreasing angle between the fracture and the minimum in situ stress. Our findings seem to invalidate the use of the fracture initiation pressure and the formation breakdown pressure for stress measurements or rock strength evaluation purposes.
Holden, Mark D; Buck, Era; Luk, John; Ambriz, Frank; Boisaubin, Eugene V; Clark, Mark A; Mihalic, Angela P; Sadler, John Z; Sapire, Kenneth J; Spike, Jeffrey P; Vince, Alan; Dalrymple, John L
2015-06-01
The University of Texas System established the Transformation in Medical Education (TIME) initiative to reconfigure and shorten medical education from college matriculation through medical school graduation. One of the key changes proposed as part of the TIME initiative was to begin emphasizing professional identity formation (PIF) at the premedical level. The TIME Steering Committee appointed an interdisciplinary task force to explore the fundamentals of PIF and to formulate strategies that would help students develop their professional identity as they transform into physicians. In this article, the authors describe the task force's process for defining PIF and developing a framework, which includes 10 key aspects, 6 domains, and 30 subdomains to characterize the complexity of physician identity. The task force mapped this framework onto three developmental phases of medical education typified by the undergraduate student, the clerkship-level medical student, and the graduating medical student. The task force provided strategies for the promotion and assessment of PIF for each subdomain at each of the three phases, in addition to references and resources. Assessments were suggested for student feedback, curriculum evaluation, and theoretical development. The authors emphasize the importance of longitudinal, formative assessment using a combination of existing assessment methods. Though not unique to the medical profession, PIF is critical to the practice of exemplary medicine and the well-being of patients and physicians.
Better Care Teams: A Stepwise Skill Reinforcement Model.
Christopher, Beth-Anne; Grantner, Mary; Coke, Lola A; Wideman, Marilyn; Kwakwa, Francis
2016-06-01
The Building Healthy Urban Communities initiative presents a path for organizations partnering to improve patient outcomes with continuing education (CE) as a key component. Components of the CE initiative included traditional CE delivery formats with an essential element of adaptability and new methods, with rigorous evaluation over time that included evaluation prior to the course, immediately following the CE session, 6 to 8 weeks after the CE session, and then subsequent monthly "testlets." Outcome measures were designed to allow for ongoing adaptation of content, reinforcement of key learning objectives, and use of innovative concordant testing and retrieval practice techniques. The results after 1 year of programming suggest the stepwise skill reinforcement model is effective for learning and is an efficient use of financial and human resources. More important, its design is one that could be adopted at low cost by organizations willing to work in close partnership. J Contin Educ Nurs. 2016;47(6):283-288. Copyright 2016, SLACK Incorporated.
NASA Astrophysics Data System (ADS)
Anaperta, M.; Helendra, H.; Zulva, R.
2018-04-01
This study aims to describe the validity of physics module with Character Oriented Values Using Process Approach Skills at Dynamic Electrical Material in high school physics / MA and SMK. The type of research is development research. The module development model uses the development model proposed by Plomp which consists of (1) preliminary research phase, (2) the prototyping phase, and (3) assessment phase. In this research is done is initial investigation phase and designing. Data collecting technique to know validation is observation and questionnaire. In the initial investigative phase, curriculum analysis, student analysis, and concept analysis were conducted. In the design phase and the realization of module design for SMA / MA and SMK subjects in dynamic electrical materials. After that, the formative evaluation which include self evaluation, prototyping (expert reviews, one-to-one, and small group. At this stage validity is performed. This research data is obtained through the module validation sheet, which then generates a valid module.
Xiang, Ning; Lyu, Yuan; Zhu, Xiao; Bhunia, Arun K; Narsimhan, Ganesan
2016-11-01
Antimicrobial peptides (AMPs) inactivate microbial cells through pore formation in cell membrane. Because of their different mode of action compared to antibiotics, AMPs can be effectively used to combat drug resistant bacteria in human health. AMPs can also be used to replace antibiotics in animal feed and immobilized on food packaging films. In this research, we developed a methodology based on mechanistic evaluation of peptide-lipid bilayer interaction to identify AMPs from soy protein. Production of AMPs from soy protein is an attractive, cost-saving alternative for commercial consideration, because soy protein is an abundant and common protein resource. This methodology is also applicable for identification of AMPs from any protein. Initial screening of peptide segments from soy glycinin (11S) and soy β-conglycinin (7S) subunits was based on their hydrophobicity, hydrophobic moment and net charge. Delicate balance between hydrophilic and hydrophobic interactions is necessary for pore formation. High hydrophobicity decreases the peptide solubility in aqueous phase whereas high hydrophilicity limits binding of the peptide to the bilayer. Out of several candidates chosen from the initial screening, two peptides satisfied the criteria for antimicrobial activity, viz. (i) lipid-peptide binding in surface state and (ii) pore formation in transmembrane state of the aggregate. This method of identification of antimicrobial activity via molecular dynamics simulation was shown to be robust in that it is insensitive to the number of peptides employed in the simulation, initial peptide structure and force field. Their antimicrobial activity against Listeria monocytogenes and Escherichia coli was further confirmed by spot-on-lawn test. Copyright © 2016 Elsevier Inc. All rights reserved.
Cowsert, L M; Fox, M C; Zon, G; Mirabelli, C K
1993-01-01
Papillomaviruses induce benign proliferative lesions, such as genital warts, in humans. The E2 gene product is thought to play a major role in the regulation of viral transcription and DNA replication and may represent a rational target for an antisense oligonucleotide drug action. Phosphorothioate oligonucleotides complementary to E2 mRNAs were synthesized and tested in a series of in vitro bovine papillomavirus (BPV) and human papillomavirus (HPV) models for the ability to inhibit E2 transactivation and virus-induced focus formation. The most active BPV-specific compounds were complementary to the mRNA cap region (ISIS 1751), the translation initiation region for the full-length E2 transactivator (ISIS 1753), and the translation initiation region for the E2 transrepressor mRNA (ISIS 1755). ISIS 1751 and ISIS 1753 were found to reduce E2-dependent transactivation and viral focus formation in a sequence-specific and concentration-dependent manner. ISIS 1755 increased E2 transactivation in a dose-dependent manner but had no effect on focus formation. Oligonucleotides with a chain length of 20 residues had optimal activity in the E2 transactivation assay. On the basis of the above observations, ISIS 2105, a 20-residue phosphorothioate oligonucleotide targeted to the translation initiation of both HPV type 6 (HPV-6) and HPV-11 E2 mRNA, was designed and shown to inhibit E2-dependent transactivation by HPV-11 E2 expressed from a surrogate promoter. These observations support the rationale of E2 as a target for antiviral therapy against papillomavirus infections and specifically identify ISIS 2105 as a candidate antisense oligonucleotide for the treatment of genital warts induced by HPV-6 and HPV-11. Images PMID:8383937
An evaluation of the process and initial impact of disseminating a nursing e-thesis.
Macduff, Colin
2009-05-01
This paper is a report of a study conducted to evaluate product, process and outcome aspects of the dissemination of a nursing PhD thesis via an open-access electronic institutional repository. Despite the growth of university institutional repositories which make theses easily accessible via the world wide web, nursing has been very slow to evaluate related processes and outcomes. Drawing on Stake's evaluation research methods, a case study design was adopted. The case is described using a four-phase structure within which key aspects of process and impact are reflexively analysed. In the conceptualization/re-conceptualization phase, fundamental questions about the purpose, format and imagined readership for a published nursing PhD were considered. In the preparation phase, seven key practical processes were identified that are likely to be relevant to most e-theses. In the dissemination phase email invitations were primarily used to invite engagement. The evaluation phase involved quantitative indicators of initial impact, such as page viewing and download statistics and qualitative feedback on processes and product. Analysis of process and impact elements of e-thesis dissemination is likely to have more than intrinsic value. The advent of e-theses housed in web-based institutional repositories has the potential to transform thesis access and use. It also offers potential to transform the nature and scope of thesis production and dissemination. Nursing scholars can exploit and evaluate such opportunities.
Considering mutagenicity and genotoxicity in the cancer mode ...
It is well known that genotoxicity plays a significant role in the development of tumor formation. Mutations in somatic cells can play a key role early in cancer initiation and might affect other stages of the carcinogenic process. Determination of carcinogens that operate through a genotoxic mode of action entails evaluation of the available data. One way of determining if a chemical is acting through a genotoxic mechanism is to assemble the relevant data (human, animal, in vivo, in vitro) of individual genetic end points, evaluating the data against a current acceptance criteria (study quality, methodology used etc.), and determining the weight of evidence based on both the available data as well as evaluating against other existing information such as epidemiological data, ADME information etc. This presentation will lay-out key, currently available genotoxicity information on naphthalene, styrene and ethylbenzene. These three chemicals were chosen because all three chemicals cause mouse lung tumors, in particular bronchiolar-alveolar adenomas and carcinomas. This analysis of the data will enable further understanding of the mode of action of mouse lung tumor formation and species differences, which will impact the hazard identification and use of mode of action in the risk assessment of naphthalene, styrene, and ethylbenzene.
Assessment of dental plaque by optoelectronic methods
NASA Astrophysics Data System (ADS)
Negrutiu, Meda-Lavinia; Sinescu, Cosmin; Bortun, Cristina Maria; Levai, Mihaela-Codrina; Topala, Florin Ionel; Crǎciunescu, Emanuela Lidia; Cojocariu, Andreea Codruta; Duma, Virgil Florin; Podoleanu, Adrian Gh.
2016-03-01
The formation of dental biofilm follows specific mechanisms of initial colonization on the surface, microcolony formation, development of organized three dimensional community structures, and detachment from the surface. The structure of the plaque biofilm might restrict the penetration of antimicrobial agents, while bacteria on a surface grow slowly and display a novel phenotype; the consequence of the latter is a reduced sensitivity to inhibitors. The aim of this study was to evaluate with different optoelectronic methods the morphological characteristics of the dental biofilm. The study was performed on samples from 25 patients aged between 18 and 35 years. The methods used in this study were Spectral Domain Optical Coherence Tomography (SD-OCT) working at 870 nm for in vivo evaluations and Scanning Electron Microscopy (SEM) for validations. For each patient a sample of dental biofilm was obtained directly from the vestibular surface of the teeth's. SD-OCT produced C- and B-scans that were used to generate three dimensional (3D) reconstructions of the sample. The results were compared with SEM evaluations. The biofilm network was dramatically destroyed after the professional dental cleaning. OCT noninvasive methods can act as a valuable tool for the 3D characterization of dental biofilms.
NASA Astrophysics Data System (ADS)
Youssefi, Somayeh; Waring, Michael S.
2015-07-01
The ozonolysis of reactive organic gases (ROG), e.g. terpenes, generates secondary organic aerosol (SOA) indoors. The SOA formation strength of such reactions is parameterized by the aerosol mass fraction (AMF), a.k.a. SOA yield, which is the mass ratio of generated SOA to oxidized ROG. AMFs vary in magnitude both among and for individual ROGs. Here, we quantified dynamic SOA formation from the ozonolysis of α-pinene with 'transient AMFs,' which describe SOA formation due to pulse emission of a ROG in an indoor space with air exchange, as is common when consumer products are intermittently used in ventilated buildings. We performed 19 experiments at low, moderate, and high (0.30, 0.52, and 0.94 h-1, respectively) air exchange rates (AER) at varying concentrations of initial reactants. Transient AMFs as a function of peak SOA concentrations ranged from 0.071 to 0.25, and they tended to increase as the AER and product of the initial reactant concentrations increased. Compared to our similar research on limonene ozonolysis (Youssefi and Waring, 2014), for which formation strength was driven by secondary ozone reactions, the AER impact for α-pinene was opposite in direction and weaker, while the initial reactant product impact was in the same direction but stronger for α-pinene than for limonene. Linear fits of AMFs for α-pinene ozonolysis as a function of the AER and initial reactant concentrations are provided so that future indoor models can predict SOA formation strength.
Lulli, Matteo; Cammalleri, Maurizio; Granucci, Irene; Witort, Ewa; Bono, Silvia; Di Gesualdo, Federico; Lupia, Antonella; Loffredo, Rosa; Casini, Giovanni; Dal Monte, Massimo; Capaccioli, Sergio
2017-08-26
Neoangiogenesis is the main pathogenic event involved in a variety of retinal diseases. It has been recently demonstrated that inhibiting the urokinase-type plasminogen activator receptor (uPAR) results in reduced angiogenesis in a mouse model of oxygen-induced retinopathy (OIR), establishing uPAR as a therapeutic target in proliferative retinopathies. Here, we evaluated in cultured human retinal endothelial cells (HRECs) and in OIR mice the potential of a specific antisense oligodeoxyribonucleotide (ASO) in blocking the synthesis of uPAR and in providing antiangiogenic effects. uPAR expression in HRECs was inhibited by lipofection with the phosphorotioated 5'-CGGCGGGTGACCCATGTG-3' ASO-uPAR, complementary to the initial translation site of uPAR mRNA. Inhibition of uPAR expression via ASO-uPAR was evaluated in HRECs by analyzing VEGF-induced tube formation and migration. In addition, the well-established and reproducible murine OIR model was used to induce retinal neovascularization in vivo. OIR mice were injected intraperitoneally with ASO-uPAR and retinopathy was evaluated considering the extent of the avascular area in the central retina and neovascular tuft formation. The ASO-uPAR specifically decreased uPAR mRNA and protein levels in HRECs and mitigated VEGF-induced tube formation and cell migration. Noteworthy, in OIR mice ASO-uPAR administration reduced both the avascular area and the formation of neovascular tufts. In conclusion, although the extrapolation of these experimental findings to the clinic is not straightforward, ASO-uPAR may be considered a potential therapeutic tool for treatment of proliferative retinal diseases. Copyright © 2017 Elsevier Inc. All rights reserved.
Matsumoto, Kouichi; Fujie, Shunsuke; Suga, Seiji; Nokami, Toshiki; Yoshida, Jun-ichi
2009-09-28
A catalytic amount of electrochemically generated "ArS+" ("ArS+" = ArS(ArSSAr)+) initiates a cation chain reaction of dienes that involves the addition of ArSSAr associated with stereoselective intramolecular carbon-carbon bond formation, and the direct (in-cell) electrolysis of a mixture of a diene and ArSSAr with a catalytic amount of electricity also effectively initiates the reaction.
NASA Astrophysics Data System (ADS)
Tovpinets, A. O.; Leytsin, V. N.; Dmitrieva, M. A.; Ivonin, I. V.; Ponomarev, S. V.
2017-12-01
The solution of the tasks in the field of creating and processing materials for additive technologies requires the development of a single theory of materials for various applications and processes. A separate class of materials that are promising for use in additive technologies includes materials whose consolidation is ensured by the presence of low-melting components in the initial mixture which form a matrix at a temperature not exceeding the melting point, recrystallization or destruction of any of the responsible refractory components of the initial dispersion. The study of the contribution of the binder thermal destruction to the structure and phase composition of the initial compact of the future composite is essential for the development of modern technologies for the synthesis of low-temperature ceramics. This paper investigates the effect of the thermal destruction of a binder on the formation of a green compact of low-temperature ceramics and the structural-mechanical characteristics of sintered ceramics. The approach proposed in Ref. [1] for evaluating the structure and physical characteristics of sintered low-temperature ceramics is improved to clarify the structure of green compacts obtained after thermal destruction of the polymer binder, with taking into account the pores formed and the infusible residue. The obtained results enable a more accurate prediction of thermal stresses in the matrix of sintered ceramics and serve as a basis for optimization.
Shellenberger, Sylvia; Seale, J Paul; Harris, Dona L; Johnson, J Aaron; Dodrill, Carrie L; Velasquez, Mary M
2009-03-01
Educational research demonstrates little evidence of long-term retention from traditional lectures in residency programs. Team-based learning (TBL), an alternative, active learning technique, incites competition and generates discussion. This report presents data evaluating the ability of TBL to reinforce and enhance concepts taught during initial training in a National Institutes of Health-funded alcohol screening and brief intervention (SBI) program conducted in eight residency programs from 2005 to 2007 under the auspices of Mercer University School of Medicine. After initial training of three hours, the authors conducted three TBL booster sessions of one and a quarter hours, spaced four months apart at each site. They assessed feasibility through the amount of preparation time for faculty and staff, residents' evaluations of their training, self-reported use of SBI, residents' performance on individual quizzes compared with group quizzes, booster session evaluations, and levels of confidence in conducting SBI. After initial training and three TBL reinforcement sessions, 42 residents (63%) reported that they performed SBI and that their levels of confidence in performing interventions in their current and future practices was moderately high. Participants preferred TBL formats over lectures. Group performance was superior to individual performance on initial assessments. When invited to select a model for conducting SBI in current and future practices, all residents opted for procedures that included clinician involvement. Faculty found TBL to be efficient but labor-intensive for training large groups. TBL was well received by residents and helped maintain a newly learned clinical skill. Future research should compare TBL to other learning methods.
Geoscientific Site Evaluation Approach for Canada's Deep Geological Repository for Used Nuclear Fuel
NASA Astrophysics Data System (ADS)
Sanchez-Rico Castejon, M.; Hirschorn, S.; Ben Belfadhel, M.
2015-12-01
The Nuclear Waste Management Organization (NWMO) is responsible for implementing Adaptive Phased Management, the approach selected by the Government of Canada for long-term management of used nuclear fuel generated by Canadian nuclear reactors. The ultimate objective of APM is the centralized containment and isolation of Canada's used nuclear fuel in a Deep Geological Repository in a suitable crystalline or sedimentary rock formation. In May 2010, the NWMO published and initiated a nine-step site selection process to find an informed and willing community to host a deep geological repository for Canada's used nuclear fuel. The site selection process is designed to address a broad range of technical and social, economic and cultural factors. The site evaluation process includes three main technical evaluation steps: Initial Screenings; Preliminary Assessments; and Detailed Site Characterizations, to assess the suitability of candidate areas in a stepwise manner over a period of many years. By the end of 2012, twenty two communities had expressed interest in learning more about the project. As of July 2015, nine communities remain in the site selection process. To date (July 2015), NWMO has completed Initial Screenings for the 22 communities that expressed interest, and has completed the first phase of Preliminary Assessments (desktop) for 20 of the communities. Phase 2 of the Preliminary Assessments has been initiated in a number of communities, with field activities such as high-resolution airborne geophysical surveys and geological mapping. This paper describes the approach, methods and criteria being used to assess the geoscientific suitability of communities currently involved in the site selection process.
Sorensen, Mathew D; Chi, Thomas; Shara, Nawar M; Wang, Hong; Hsi, Ryan S; Orchard, Tonya; Kahn, Arnold J; Jackson, Rebecca D; Miller, Joe; Reiner, Alex P; Stoller, Marshall L
2014-02-01
Obesity is a strong risk factor for nephrolithiasis, but the role of physical activity and caloric intake remains poorly understood. We evaluated this relationship in 84,225 women with no history of stones as part of the Women's Health Initiative Observational Study, a longitudinal, prospective cohort of postmenopausal women enrolled from 1993 to 1998 with 8 years' median follow-up. The independent association of physical activity (metabolic equivalents [METs]/wk), calibrated dietary energy intake, and body mass index (BMI) with incident kidney stone development was evaluated after adjustment for nephrolithiasis risk factors. Activity intensity was evaluated in stratified analyses. Compared with the risk in inactive women, the risk of incident stones decreased by 16% in women with the lowest physical activity level (adjusted hazard ratio [aHR], 0.84; 95% confidence interval [95% CI], 0.74 to 0.97). As activity increased, the risk of incident stones continued to decline until plateauing at a decrease of approximately 31% for activity levels ≥10 METs/wk (aHR, 0.69; 95% CI, 0.60 to 0.79). Intensity of activity was not associated with stone formation. As dietary energy intake increased, the risk of incident stones increased by up to 42% (aHR, 1.42; 95% CI, 1.02 to 1.98). However, intake <1800 kcal/d did not protect against stone formation. Higher BMI category was associated with increased risk of incident stones. In summary, physical activity may reduce the risk of incident kidney stones in postmenopausal women independent of caloric intake and BMI, primarily because of the amount of activity rather than exercise intensity. Higher caloric intake further increases the risk of incident stones.
Toonstra, Amy L; Nelliot, Archana; Aronson Friedman, Lisa; Zanni, Jennifer M; Hodgson, Carol; Needham, Dale M
2017-06-01
Knowledge-related barriers to safely implement early rehabilitation programs in intensive care units (ICUs) may be overcome via targeted education. The purpose of this study was to evaluate the effectiveness of an interactive educational session on short-term knowledge of clinical decision-making for safe rehabilitation of patients in ICUs. A case-based teaching approach, drawing from published safety recommendations for initiation of rehabilitation in ICUs, was used with a multidisciplinary audience. An audience response system was incorporated to promote interaction and evaluate knowledge before vs. after the educational session. Up to 175 audience members, of 271 in attendance (129 (48%) physical therapists, 51 (19%) occupational therapists, 31 (11%) nursing, 14 (5%) physician, 46 (17%) other), completed both the pre- and post-test questions for each of the six unique patient cases. In four of six patient cases, there was a significant (p< 0.001) increase in identifying the correct answer regarding initiation of rehabilitation activities. This learning effect was similar irrespective of participants' years of experience and clinical discipline. An interactive, case-based, educational session may be effective for increasing short-term knowledge, and identifying knowledge gaps, regarding clinical decision-making for safe rehabilitation of patients in ICUs. Implications for Rehabilitation Lack of knowledge regarding the safety considerations for early rehabilitation of ICU patients is a barrier to implementing early rehabilitation. Interactive educational formats, such as the use of audience response systems, offer a new method of teaching and instantly assessing learning of clinically important information. In a small study, we have shown that an interactive, case-based educational format may be used to effectively teach clinical decision-making for the safe rehabilitation of ICU patients to a diverse audience of clinicians.
Bustillo-Avendaño, Estefano; Ibáñez, Sergio; Sanz, Oscar; Sousa Barros, Jessica Aline; Gude, Inmaculada; Perianez-Rodriguez, Juan; Micol, José Luis; Del Pozo, Juan Carlos
2018-01-01
Body regeneration through formation of new organs is a major question in developmental biology. We investigated de novo root formation using whole leaves of Arabidopsis (Arabidopsis thaliana). Our results show that local cytokinin biosynthesis and auxin biosynthesis in the leaf blade followed by auxin long-distance transport to the petiole leads to proliferation of J0121-marked xylem-associated tissues and others through signaling of INDOLE-3-ACETIC ACID INDUCIBLE28 (IAA28), CRANE (IAA18), WOODEN LEG, and ARABIDOPSIS RESPONSE REGULATORS1 (ARR1), ARR10, and ARR12. Vasculature proliferation also involves the cell cycle regulator KIP-RELATED PROTEIN2 and ABERRANT LATERAL ROOT FORMATION4, resulting in a mass of cells with rooting competence that resembles callus formation. Endogenous callus formation precedes specification of postembryonic root founder cells, from which roots are initiated through the activity of SHORT-ROOT, PLETHORA1 (PLT1), and PLT2. Primordia initiation is blocked in shr plt1 plt2 mutant. Stem cell regulators SCHIZORIZA, JACKDAW, BLUEJAY, and SCARECROW also participate in root initiation and are required to pattern the new organ, as mutants show disorganized and reduced number of layers and tissue initials resulting in reduced rooting. Our work provides an organ regeneration model through de novo root formation, stating key stages and the primary pathways involved. PMID:29233938
Bustillo-Avendaño, Estefano; Ibáñez, Sergio; Sanz, Oscar; Sousa Barros, Jessica Aline; Gude, Inmaculada; Perianez-Rodriguez, Juan; Micol, José Luis; Del Pozo, Juan Carlos; Moreno-Risueno, Miguel Angel; Pérez-Pérez, José Manuel
2018-02-01
Body regeneration through formation of new organs is a major question in developmental biology. We investigated de novo root formation using whole leaves of Arabidopsis ( Arabidopsis thaliana ). Our results show that local cytokinin biosynthesis and auxin biosynthesis in the leaf blade followed by auxin long-distance transport to the petiole leads to proliferation of J0121-marked xylem-associated tissues and others through signaling of INDOLE-3-ACETIC ACID INDUCIBLE28 (IAA28), CRANE (IAA18), WOODEN LEG, and ARABIDOPSIS RESPONSE REGULATORS1 (ARR1), ARR10, and ARR12. Vasculature proliferation also involves the cell cycle regulator KIP-RELATED PROTEIN2 and ABERRANT LATERAL ROOT FORMATION4, resulting in a mass of cells with rooting competence that resembles callus formation. Endogenous callus formation precedes specification of postembryonic root founder cells, from which roots are initiated through the activity of SHORT-ROOT, PLETHORA1 (PLT1), and PLT2. Primordia initiation is blocked in shr plt1 plt2 mutant. Stem cell regulators SCHIZORIZA, JACKDAW, BLUEJAY, and SCARECROW also participate in root initiation and are required to pattern the new organ, as mutants show disorganized and reduced number of layers and tissue initials resulting in reduced rooting. Our work provides an organ regeneration model through de novo root formation, stating key stages and the primary pathways involved. © 2018 American Society of Plant Biologists. All Rights Reserved.
Phase formation in selected surface-roughened plasma-nitrided 304 austenite stainless steel.
Singh, Gajendra Prasad; Joseph, Alphonsa; Raole, Prakash Manohar; Barhai, Prema Kanta; Mukherjee, Subroto
2008-04-01
Direct current (DC) glow discharge plasma nitriding was carried out on three selected surface-roughened AISI 304 stainless steel samples at 833 K under 4 mbar pressures for 24 h in the presence of N 2 :H 2 gas mixtures of 50 : 50 ratios. After plasma nitriding, the phase formation, case depth, surface roughness, and microhardness of a plasma-nitrided layer were evaluated by glancing angle x-ray diffractogram, optical microscope, stylus profilometer, and Vickers microhardness tester techniques. The case depth, surface hardness, and phase formation variations were observed with a variation in initial surface roughness. The diffraction patterns of the plasma-nitrided samples showed the modified intensities of the α and γ phases along with those of the CrN, Fe 4 N, and Fe 3 N phases. Hardness and case depth variations were observed with a variation in surface roughness. A maximum hardness of 1058 Hv and a case depth of 95 μm were achieved in least surface-roughened samples.
Hanass-Hancock, Jill; Alli, Farzana
2015-01-01
HIV and disability are interrelated providing a double burden to HIV endemic countries in East and Southern Africa and their already fragile health systems. Although literature reveals that people with disabilities are particularly vulnerable to HIV and that HIV, its opportunistic infections and treatments can cause disability, only few interventions target this issue and none have been evaluated in this region. Formative evaluation was undertaken with regard to the effectiveness of a workshop-based intervention for healthcare workers and people with disabilities on the intersection of disability and HIV in order to inform the further development of this intervention. The formative evaluation assessed participants' perception of the inclusion of disability in HIV services and of opportunities to initiate change after the workshops. It also captured their experiences in utilising knowledge and skills after the workshops using quantitative (short checklist and ranking exercise) and qualitative (semi-structured interviews) methods of inquiry. Frequencies and conventional content analysis were used in the analysis of the data. This study presents an example of applied research conducted under real-world conditions. 60 healthcare workers and people with disabilities took part in this pilot workshop training and participated in the formative evaluation. Healthcare workers and people with disabilities alike identified various barriers to access health services. Reasonable accommodation was perceived as being mainly absent by most participants, while some participants indicated a lack of physical accessibility in the form of universal design. Participants also identified a lack of integration of services and disability-related skills within the healthcare staff. Participants reported a number of enablers, success and challenges while implementing the knowledge from the workshops related to structural issues, service provision and integration. While participants worked on health workers' attitudes and accessibility of services, screening and referrals practice was not improved through the workshops. Formative evaluation indicates that the workshops can be effective not only in sensitising healthcare workers and people with disabilities to opportunities to improve services for people with disabilities but also to provide knowledge and skills to initiate improvements. Skills that need more practical training (e.g. screening for disability) need to be trained in more detail, and this will inform the adaptation of the workshops. However, the workshop evaluation also revealed that without policy implementation and budget allocations this change would only be limited. Implications for Rehabilitation HIV, its co-morbidities and treatments cause health conditions and impairments that have the potential to develop into disability. People with disabilities are at increased risk of exposure to HIV. Rehabilitation professionals, healthcare workers and people with disabilities can be sensitised in a three-day workshop on the relationship of disability and HIV. However, the trained participants can only implement no or low-cost elements of interventions, while high-cost interventions need budget allocations at provincial and national level.
Mechanics of graben formation in crustal rocks - A finite element analysis
NASA Technical Reports Server (NTRS)
Melosh, H. J.; Williams, C. A., Jr.
1989-01-01
The mechanics of the initial stages of graben formation are examined, showing that the configuration of a graben (a pair of antithetically dipping normal faults) is the most energetically favorable fault configuration in elastic-brittle rocks subjected to pure extension. The stress field in the vicinity of a single initial normal fault is computed with a two-dimensional FEM. It is concluded that the major factor controlling graben width is the depth of the initial fault.
Scott, Bonnie M; Schmitt, Andrew L; Livingston, Ronald B
2016-01-01
The effects of medication on neuropsychological performance have yet to be fully investigated, particularly in older patients. As such, the present case study was undertaken to examine the specific impact of benzodiazepine use on neuropsychological performance by providing a comparison of the test-retest data of an 81-year-old patient taking lorazepam. A comprehensive neuropsychological evaluation was conducted: (a) during the initial referral, while the patient had been taking high doses of lorazepam for approximately 3 years; and (b) 6 months after complete titration, which was 1 year after the initial evaluation. Normative scores derived from the 2 trials were compared via calculation of Reliable Change Indexes. Neuropsychological performance during both evaluations was indicative of dementia, including similar degrees of impairment in delayed memory, verbal fluency, and olfaction. However, scores obtained during the second evaluation were somewhat higher, with significant improvements observed in immediate memory, visuospatial/construction abilities, language function, abstract concept formation, and set shifting. Results of the current case study suggest that several neuropsychological domains may be particularly sensitive to chronic benzodiazepine use. Although the overall diagnostic picture in the present study remained unaltered, clinicians should be cognizant of such medication effects and the potential for these neuropsychological alterations to obscure differential diagnosis.
The Formation of Initial Components of Number Concepts in Mexican Children
ERIC Educational Resources Information Center
Solovieva, Yulia; Quintanar, Luis; Ortiz, Gerardo
2012-01-01
The initial formation of number concept represents one of the essential aspects of learning mathematics at the primary school. Children commonly show strong difficulties and absence of comprehension of symbolic and abstract nature of concept of number. The objective of the present study was to show the effectiveness of original method for…
Formative Assessment, Communication Skills and ICT in Initial Teacher Training
ERIC Educational Resources Information Center
Romero-Martín, M. Rosario; Castejón-Oliva, Francisco-Javier; López-Pastor, Víctor-Manuel; Fraile-Aranda, Antonio
2017-01-01
The purpose of this study is to analyze the perception of students, graduates, and lecturers in relation to systems of formative and shared assessment and to the acquisition of teaching competences regarding communication and the use of Information and Communications Technology (ICT) in initial teacher education (ITE) on degrees in Primary…
1993-01-01
Xenopus egg extracts prepared before and after egg activation retain M- and S-phase specific activity, respectively. Staurosporine, a potent inhibitor of protein kinase, converted M-phase extracts into interphase- like extracts that were capable of forming nuclei upon the addition of sperm DNA. The nuclei formed in the staurosporine treated M-phase extract were incapable of replicating DNA, and they were unable to initiate replication upon the addition of S-phase extracts. Furthermore, replication was inhibited when the staurosporine-treated M- phase extract was added in excess to the staurosporine-treated S-phase extract before the addition of DNA. The membrane-depleted S-phase extract supported neither nuclear formation nor replication; however, preincubation of sperm DNA with these extracts allowed them to form replication-competent nuclei upon the addition of excess staurosporine- treated M-phase extract. These results demonstrate that positive factors in the S-phase extracts determined the initiation of DNA replication before nuclear formation, although these factors were unable to initiate replication after nuclear formation. PMID:8253833
Formative and Summative Evaluation: Related Issues in Performance Measurement.
ERIC Educational Resources Information Center
Wholey, Joseph S.
1996-01-01
Performance measurement can serve both formative and summative evaluation functions. Formative evaluation is typically more useful for government purposes whereas performance measurement is more useful than one-shot evaluations of either formative or summative nature. Evaluators should study performance measurement through case studies and…
NASA Technical Reports Server (NTRS)
Desai, Tapan G.; Lawson, John W.; Keblinski, Pawel
2010-01-01
Reactive molecular dynamics simulations are used to study initial stage of pyrolysis of ablation materials and their composites with carbon nanotubes and carbon fibers. The products formed during pyrolysis are characterized and water is found as the primary product in all cases. The water formation mechanisms are analyzed and the value of the activation energy for water formation is estimated. A detailed study on graphitic precursor formation reveals the presence of two temperature zones. In the lower temperature zone (less than 2000 K) polymerization occurs resulting in formation of large, stable graphitic precursors, and in the high temperature zone (greater than 2000 K) polymer scission results in formation of short polymer chains/molecules. Simulations performed in the high temperature zone on the phenolic resin composites (with carbon nanotubes and carbon fibers) shows that the presence of interfaces had no substantial effect on the chain scission rate or the activation energy value for water formation.
Augmented Fish Health Monitoring; Volume I of II, Completion Report.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Michak, Patty
1991-05-01
The Bonneville Power Administration (BPA) initiated the Augmented Fish Health Monitoring project in 1986. This project was a five year interagency project involving fish rearing agencies in the Columbia Basin. Historically, all agencies involved with fish health in the Columbia Basin were conducting various levels of fish health monitoring, pathogen screening and collection. The goals of this project were; to identify, develop and implement a standardized level of fish health methodologies, develop a common data collection and reporting format in the area of artificial production, evaluate and monitor water quality, improve communications between agencies and provide annual evaluation of fishmore » health information for production of healthier smolts. This completion report will contain a project evaluation, review of the goals of the project, evaluation of the specific fish health analyses, an overview of highlights of the project and concluding remarks. 8 refs., 1 fig., 4 tabs.« less
Boerebach, Benjamin C M; Lombarts, Kiki M J M H; Arah, Onyebuchi A
2016-03-01
The System for Evaluation of Teaching Qualities (SETQ) was developed as a formative system for the continuous evaluation and development of physicians' teaching performance in graduate medical training. It has been seven years since the introduction and initial exploratory psychometric analysis of the SETQ questionnaires. This study investigates the validity and reliability of the SETQ questionnaires across hospitals and medical specialties using confirmatory factor analyses (CFAs), reliability analysis, and generalizability analysis. The SETQ questionnaires were tested in a sample of 3,025 physicians and 2,848 trainees in 46 hospitals. The CFA revealed acceptable fit of the data to the previously identified five-factor model. The high internal consistency estimates suggest satisfactory reliability of the subscales. These results provide robust evidence for the validity and reliability of the SETQ questionnaires for evaluating physicians' teaching performance. © The Author(s) 2014.
Federal Register 2010, 2011, 2012, 2013, 2014
2011-10-28
...The Alliance for Nanotechnology in Cancer of the National Cancer Institute (NCI) is initiating a public private industry partnership called TONIC (Translation Of Nanotechnology In Cancer) to promote translational research and development opportunities of nanotechnology-based cancer solutions. An immediate consequence of this effort will be the formation of a consortium involving government and pharmaceutical, and biotechnology companies. This consortium will evaluate promising nanotechnology platforms and facilitate their successful translation from academic research to clinical environment, resulting in safe, timely, effective and novel diagnosis and treatment options for cancer patients. The purpose of this notice is to inform the community about the Alliance for Nanotechnology in Cancer of NCI's intention to form the consortium and to invite eligible companies (as defined in last paragraph) to participate.
ArrayInitiative - a tool that simplifies creating custom Affymetrix CDFs
2011-01-01
Background Probes on a microarray represent a frozen view of a genome and are quickly outdated when new sequencing studies extend our knowledge, resulting in significant measurement error when analyzing any microarray experiment. There are several bioinformatics approaches to improve probe assignments, but without in-house programming expertise, standardizing these custom array specifications as a usable file (e.g. as Affymetrix CDFs) is difficult, owing mostly to the complexity of the specification file format. However, without correctly standardized files there is a significant barrier for testing competing analysis approaches since this file is one of the required inputs for many commonly used algorithms. The need to test combinations of probe assignments and analysis algorithms led us to develop ArrayInitiative, a tool for creating and managing custom array specifications. Results ArrayInitiative is a standalone, cross-platform, rich client desktop application for creating correctly formatted, custom versions of manufacturer-provided (default) array specifications, requiring only minimal knowledge of the array specification rules and file formats. Users can import default array specifications, import probe sequences for a default array specification, design and import a custom array specification, export any array specification to multiple output formats, export the probe sequences for any array specification and browse high-level information about the microarray, such as version and number of probes. The initial release of ArrayInitiative supports the Affymetrix 3' IVT expression arrays we currently analyze, but as an open source application, we hope that others will contribute modules for other platforms. Conclusions ArrayInitiative allows researchers to create new array specifications, in a standard format, based upon their own requirements. This makes it easier to test competing design and analysis strategies that depend on probe definitions. Since the custom array specifications are easily exported to the manufacturer's standard format, researchers can analyze these customized microarray experiments using established software tools, such as those available in Bioconductor. PMID:21548938
Model for economic evaluation of high energy gas fracturing
DOE Office of Scientific and Technical Information (OSTI.GOV)
Engi, D.
1984-05-01
The HEGF/NPV model has been developed and adapted for interactive microcomputer calculations of the economic consequences of reservoir stimulation by high energy gas fracturing (HEGF) in naturally fractured formations. This model makes use of three individual models: a model of the stimulated reservoir, a model of the gas flow in this reservoir, and a model of the discounted expected net cash flow (net present value, or NPV) associated with the enhanced gas production. Nominal values of the input parameters, based on observed data and reasonable estimates, are used to calculate the initial expected increase in the average daily rate ofmore » production resulting from the Meigs County HEGF stimulation experiment. Agreement with the observed initial increase in rate is good. On the basis of this calculation, production from the Meigs County Well is not expected to be profitable, but the HEGF/NPV model probably provides conservative results. Furthermore, analyses of the sensitivity of the expected NPV to variations in the values of certain reservoir parameters suggest that the use of HEGF stimulation in somewhat more favorable formations is potentially profitable. 6 references, 4 figures, 3 tables.« less
Gomes, Marcelo Pedrosa; Juneau, Philippe
2016-11-01
We investigated the physiological responses of Lemna minor plants exposed to glyphosate. The deleterious effects of this herbicide on photosynthesis, respiration, and pigment concentrations were related to glyphosate-induced oxidative stress through hydrogen peroxide (H 2 O 2 ) accumulation. By using photosynthetic and respiratory electron transport chain (ETC) inhibitors we located the primary site of reactive oxygen species (ROS) production in plants exposed to 500 mg glyphosate l -1 . Inhibition of mitochondrial ETC Complex I by rotenone reduced H 2 O 2 concentrations in glyphosate-treated plants. Complex III activity was very sensitive to glyphosate which appears to act much like antimycin A (an inhibitor of mitochondrial ETC Complex III) by shunting electrons from semiquinone to oxygen, with resulting ROS formation. Confocal evaluations for ROS localization showed that ROS are initially produced outside of the chloroplasts upon initial glyphosate exposure. Our results indicate that in addition to interfering with the shikimate pathway, glyphosate can induce oxidative stress in plants through H 2 O 2 formation by targeting the mitochondrial ETC, which would explain its observed effects on non-target organisms. Copyright © 2016 Elsevier Ltd. All rights reserved.
Bromate formation in a hybrid ozonation-ceramic membrane filtration system.
Moslemi, Mohammadreza; Davies, Simon H; Masten, Susan J
2011-11-01
The effect of pH, ozone mass injection rate, initial bromide concentration, and membrane molecular weight cut off (MWCO) on bromate formation in a hybrid membrane filtration-ozonation reactor was studied. Decreasing the pH, significantly reduced bromate formation. Bromate formation increased with increasing gaseous ozone mass injection rate, due to increase in dissolved ozone concentrations. Greater initial bromide concentrations resulted in higher bromate concentrations. An increase in the bromate concentration was observed by reducing MWCO, which resulted in a concomitant increase in the retention time in the system. A model to estimate the rate of bromate formation was developed. Good correlation between the model simulation and the experimental data was achieved. Copyright © 2011 Elsevier Ltd. All rights reserved.
Generic Ada code in the NASA space station command, control and communications environment
NASA Technical Reports Server (NTRS)
Mcdougall, D. P.; Vollman, T. E.
1986-01-01
The results of efforts to apply powerful Ada constructs to the formatted message handling process are described. The goal of these efforts was to extend the state-of-technology in message handling while at the same time producing production-quality, reusable code. The first effort was initiated in September, 1984 and delivered in April, 1985. That product, the Generic Message Handling Facility, met initial goals, was reused, and is available in the Ada Repository on ARPANET. However, it became apparent during its development that the initial approach to building a message handler template was not optimal. As a result of this initial effort, several alternate approaches were identified, and research is now on-going to identify an improved product. The ultimate goal is to be able to instantly build a message handling system for any message format given a specification of that message format. The problem lies in how to specify the message format, and one that is done, how to use that information to build the message handler. Message handling systems and message types are described. The initial efforts, its results and its shortcomings are detailed. The approach now being taken to build a system which will be significantly easier to implement, and once implemented, easier to use, is described. Finally, conclusions are offered.
Portfolios for determining initial licensure competency.
Chambers, David W
2004-02-01
Because attempts to improve initial licensure examinations have not been grounded in measurement theory, partial and inadequate remedies have led to a cycle of refutations, defenses and political polarization. The author reviewed the psychometric literature, focusing on high-stakes professional decisions. Editorials in the dental literature and position papers of involved organizations often use words from this literature without incorporating its fundamental concepts. The reliability of one-shot initial licensure examinations is estimated to be approximately r = .40, which is a value well under the standard for such tests in other professions. Validity has not been investigated rigorously, but the one-shot format and proposals to remove live patients certainly would reduce validity. The use of portfolios--a small number of evaluations in several realistic task domains--is a viable means of achieving psychometric standards for initial licensure decisions. Boards are charged with making valid and reliable licensure decisions, not with conducting examinations. At a minimum, they must define the competencies of beginning practitioners and establish the psychometric criteria for their decisions (neither of which are done currently). Gathering data then can be delegated to whoever is best qualified to meet these standards.
Shuck, Lowell Z.
1979-01-01
Subterranean earth formations containing energy values are subjected to hydraulic fracturing procedures to enhance the recovery of the energy values. These fractures are induced in the earth formation by pumping liquid into the wellbore penetrating the earth formation until the pressure of the liquid is sufficient to fracture the earth formation adjacent to the wellbore. The present invention is directed to a transducer which is positionable within the wellbore to generate a signal indicative of the fracture initiation useful for providing a timing signal to equipment for seismic mapping of the fracture as it occurs and for providing a measurement of the pressure at which the fracture is initiated.
Zhou, Tingting; Lou, Jianfeng; Zhang, Yangeng; Song, Huajie; Huang, Fenglei
2016-07-14
We report million-atom reactive molecular dynamic simulations of shock initiation of β-cyclotetramethylene tetranitramine (β-HMX) single crystals containing nanometer-scale spherical voids. Shock induced void collapse and subsequent hot spot formation as well as chemical reaction initiation are observed which depend on the void size and impact strength. For an impact velocity of 1 km s(-1) and a void radius of 4 nm, the void collapse process includes three stages; the dominant mechanism is the convergence of upstream molecules toward the centerline and the downstream surface of the void forming flowing molecules. Hot spot formation also undergoes three stages, and the principal mechanism is kinetic energy transforming to thermal energy due to the collision of flowing molecules on the downstream surface. The high temperature of the hot spot initiates a local chemical reaction, and the breakage of the N-NO2 bond plays the key role in the initial reaction mechanism. The impact strength and void size have noticeable effects on the shock dynamical process, resulting in a variation of the predominant mechanisms leading to void collapse and hot spot formation. Larger voids or stronger shocks result in more intense hot spots and, thus, more violent chemical reactions, promoting more reaction channels and generating more reaction products in a shorter duration. The reaction products are mainly concentrated in the developed hot spot, indicating that the chemical reactivity of the hmx crystal is greatly enhanced by void collapse. The detailed information derived from this study can aid a thorough understanding of the role of void collapse in hot spot formation and the chemical reaction initiation of explosives.
Formation of new stellar populations from gas accreted by massive young star clusters.
Li, Chengyuan; de Grijs, Richard; Deng, Licai; Geller, Aaron M; Xin, Yu; Hu, Yi; Faucher-Giguère, Claude-André
2016-01-28
Stars in clusters are thought to form in a single burst from a common progenitor cloud of molecular gas. However, massive, old 'globular' clusters--those with ages greater than ten billion years and masses several hundred thousand times that of the Sun--often harbour multiple stellar populations, indicating that more than one star-forming event occurred during their lifetimes. Colliding stellar winds from late-stage, asymptotic-giant-branch stars are often suggested to be triggers of second-generation star formation. For this to occur, the initial cluster masses need to be greater than a few million solar masses. Here we report observations of three massive relatively young star clusters (1-2 billion years old) in the Magellanic Clouds that show clear evidence of burst-like star formation that occurred a few hundred million years after their initial formation era. We show that such clusters could have accreted sufficient gas to form new stars if they had orbited in their host galaxies' gaseous disks throughout the period between their initial formation and the more recent bursts of star formation. This process may eventually give rise to the ubiquitous multiple stellar populations in globular clusters.
Assessing the Subsequent Effect of a Formative Evaluation on a Program.
ERIC Educational Resources Information Center
Brown, J. Lynne; Kiernan, Nancy Ellen
2001-01-01
Conducted a formative evaluation of an osteoporosis prevention health education program using several methods, including questionnaires completed by 256 women, and then compared formative evaluation results to those of a summative evaluation focusing on the same target group. Results show the usefulness of formative evaluation for strengthening…
A network architecture for precision formation flying using the IEEE 802.11 MAC Protocol
NASA Technical Reports Server (NTRS)
Clare, Loren P.; Gao, Jay L.; Jennings, Esther H.; Okino, Clayton
2005-01-01
Precision Formation Flying missions involve the tracking and maintenance of spacecraft in a desired geometric formation. The strong coupling of spacecraft in formation flying control requires inter-spacecraft communication to exchange information. In this paper, we present a network architecture that supports PFF control, from the initial random deployment phase to the final formation. We show that a suitable MAC layer for the application protocol is IEEE's 802.11 MAC protocol. IEEE 802.11 MAC has two modes of operations: DCF and PCF. We show that DCF is suitable for the initial deployment phase while switching to PCF when the spacecraft are in formation improves jitter and throughput. We also consider the effect of routing on protocol performance and suggest when it is profitable to turn off route discovery to achieve better network performance.
Li, Yafan; Wheeler, Deric L; Ananthaswamy, Honnavara N; Verma, Ajit K; Oberley, Terry D
2007-12-01
Our previous studies showed that protein kinase Cepsilon (PKCepsilon) verexpression in mouse skin resulted in metastatic squamous cell carcinoma (SCC) elicited by single 7,12-dimethylbenz(a)anthracene (DMBA)-initiation and 12-O-tetradecanoylphorbol-13-acetate (TPA)-promotion in the absence of preceding papilloma formation as is typically observed in wild type mice. The present study demonstrates that double-DMBA initiation modulates tumor incidence, multiplicity, and latency period in both wild type and PKCepsilon overexpression transgenic (PKCepsilon-Tg) mice. After 17 weeks (wks) of tumor promotion, a reduction in papilloma multiplicity was observed in double- versus single-DMBA initiated wild type mice. Papilloma multiplicity was inversely correlated with cell death indices of interfollicular keratinocytes, indicating decreased papilloma formation was caused by increased cell death and suggesting the origin of papillomas is in interfollicular epidermis. Double-initiated PKCepsilon-Tg mice had accelerated carcinoma formation and cancer incidence in comparison to single-initiated PKCepsilon-Tg mice. Morphologic analysis of mouse skin following double initiation and tumor promotion showed a similar if not identical series of events to those previously observed following single initiation and tumor promotion: putative preneoplastic cells were observed arising from hyperplastic hair follicles (HFs) with subsequent cancer cell infiltration into the dermis. Single-initiated PKCepsilon-Tg mice exhibited increased mitosis in epidermal cells of HFs during tumor promotion.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Wildfire, Christina; Sabolsky, Edward M.; Spencer, Michael J.
The rapid synthesis of yttrium aluminum garnet (Y 3Al 15O 12, YAG) powder was investigated through the use of microwave irradiation of the oxide precursor system. For this investigation, an external hybrid heating source was not used. Instead, the rapid heating of the precursor materials (yttria and alumina powders, which are typically transparent to 2.45 GHz microwaves) was initiated by mixing an intrinsic absorbing material (carbon) into the original oxide precursors. The effect of the carbon characteristics, such as carbon source, concentration, particle size, and agglomerate microstructure were evaluated on the efficiency of coupling and resultant oxide reaction. The microwavemore » power was varied to optimize the YAG conversion and eliminate intermediate phase formation. Interactions between the conductive carbon particles and the dielectric oxides within the microwave exposure produced local arching and micro-plasma formation within the powder bed, resulting in the rapid formation of the refractory YAG composition. This optimal conduction led to temperatures of 1000°C that could be achieved in less than 5 min resulting in the formation of > 90 vol% YAG. The understanding of a conductor/dielectric particulate system here, provided insight into possible application of similar systems where microwave irradiation could be used for enhanced solid-state formation, local melting events, and gas phase reactions with a composite powder media.« less
Histological and Transcriptomic Analysis during Bulbil Formation in Lilium lancifolium
Yang, Panpan; Xu, Leifeng; Xu, Hua; Tang, Yuchao; He, Guoren; Cao, Yuwei; Feng, Yayan; Yuan, Suxia; Ming, Jun
2017-01-01
Aerial bulbils are an important propagative organ, playing an important role in population expansion. However, the detailed gene regulatory patterns and molecular mechanism underlying bulbil formation remain unclear. Triploid Lilium lancifolium, which develops many aerial bulbils on the leaf axils of middle-upper stem, is a useful species for investigating bulbil formation. To investigate the mechanism of bulbil formation in triploid L. lancifolium, we performed histological and transcriptomic analyses using samples of leaf axils located in the upper and lower stem of triploid L. lancifolium during bulbil formation. Histological results indicated that the bulbils of triploid L. lancifolium are derived from axillary meristems that initiate de novo from cells on the adaxial side of the petiole base. Transcriptomic analysis generated ~650 million high-quality reads and 11,871 differentially expressed genes (DEGs). Functional analysis showed that the DEGs were significantly enriched in starch and sucrose metabolism and plant hormone signal transduction. Starch synthesis and accumulation likely promoted the initiation of upper bulbils in triploid L. lancifolium. Hormone-associated pathways exhibited distinct patterns of change in each sample. Auxin likely promoted the initiation of bulbils and then inhibited further bulbil formation. High biosynthesis and low degradation of cytokinin might have led to bulbil formation in the upper leaf axil. The present study achieved a global transcriptomic analysis focused on gene expression changes and pathways' enrichment during upper bulbil formation in triploid L. lancifolium, laying a solid foundation for future molecular studies on bulbil formation. PMID:28912794
NASA Astrophysics Data System (ADS)
Chen, Chia-Li; Li, Lijie; Tang, Ping; Cocker, David R.
2018-05-01
SOA formation is not well predicted in current models in urban area. The interaction among multiple anthropogenic volatile organic compounds is essential for the SOA formation in the complex urban atmosphere. Secondary organic aerosol (SOA) from the photooxidation of naphthalene, 1-methylnaphthalene, and 2-methylnaphthalene as well as individual polycyclic aromatic hydrocarbons (PAHs) mixed with m-xylene or an atmospheric surrogate mixture was explored in the UCR CE-CERT environmental chamber under urban relevant low NOx and extremely low NOx (H2O2) conditions. Addition of m-xylene suppressed SOA formation from the individual PAH precursor. A similar suppression effect on SOA formation was observed during the surrogate mixture photooxidation suggesting the importance of gas-phase chemical reactivity to SOA formation. The SOA growth rate for different PAH-m-xylene mixtures was strongly correlated with initial [HO2]/[RO2] ratio but negatively correlated with initial m-xylene/NO ratio. Decreasing SOA formation was observed for increasing m-xylene/PAHs ratios and increasing initial m-xylene/NO ratio. The SOA chemical composition characteristics such as f44 versus f43, H/C ratio, O/C ratio, and the oxidation state of the carbon OSbarc were consistent with a continuously aging with the SOA exhibiting characteristics of both individual precursors. SOA formation from PAHs was also suppressed within an atmospheric surrogate mixture compared to the SOA formed from individual PAHs, indicating that atmospheric reactivity directly influences SOA formation from PAHs.
Sena-Vélez, Marta; Redondo, Cristina; Graham, James H; Cubero, Jaime
2016-01-01
Xanthomonas citri subsp. citri (Xcc) A strain causes citrus bacterial canker, a serious leaf, fruit and stem spotting disease of several Citrus species. X. alfalfae subsp. citrumelonis (Xac) is the cause of citrus bacterial spot, a minor disease of citrus nursery plants and X. campestris pv. campestris (Xc) is a systemic pathogen that causes black rot of cabbage. Xanthomonas spp. form biofilms in planta that facilitate the host infection process. Herein, the role of extracellular DNA (eDNA) was evaluated in the formation and stabilization of the biofilm matrix at different stages of biofilm development. Fluorescence and light microscopy, as well as DNAse treatments, were used to determine the presence of eDNA in biofilms and bacterial cultures. DNAse treatments of Xcc strains and Xac reduced biofilm formation at the initial stage of development, as well as disrupted preformed biofilm. By comparison, no significant effect of the DNAse was detected for biofilm formation by Xc. DNAse effects on biofilm formation or disruption varied among Xcc strains and Xanthomonas species which suggest different roles for eDNA. Variation in the structure of fibers containing eDNA in biofilms, bacterial cultures, and in twitching motility was also visualized by microscopy. The proposed roles for eDNA are as an adhesin in the early stages of biofilm formation, as an structural component of mature bacterial aggregates, and twitching motility structures.
Problems and challenges of nursing students’ clinical evaluation: A qualitative study
Rafiee, Ghazanfar; Moattari, Marzieh; Nikbakht, Alireza N; Kojuri, Javad; Mousavinasab, Masoud
2014-01-01
Background: The purpose of this qualitative exploratory study was to explore the views of nursing trainers and students about nursing students’ clinical evaluation problems and drawbacks in Shiraz Nursing and Midwifery School. Materials and Methods: A qualitative exploratory approach was used in this study at Shiraz Nursing and Midwifery School in 2012. A purposeful sample of 8 nursing instructors and 40 nursing students was interviewed and the data on their opinions about the problems of the clinical evaluation were collected through semi-structured deep interviews. Initially, four open-ended questions, which were related to the clinical evaluation status, problems, were used to stimulate discussions in the interview sessions. Content analysis was employed in order to analyze the transcribed data. The recorded interviews were initially transcribed, read, and reread on a number of occasions to get an overall feeling of what the participants were saying. Each line or incident was described, and then a code, which reflected the essence of the participants’ comments, was given. Results: The codes were compared for similarity and differences, merged together, and categorized. Finally, five themes emerged: In appropriate clinical evaluation method, problems of clinical evaluation Process, problems related to clinical instructors, unsuitable programming of clinical education, and organizational shortcomings. Conclusion: Besides focusing on upgrading the current clinical evaluation forms, nursing trainers should improve their knowledge about a complete and comprehensive clinical evaluation. They should also apply other appropriate and objective clinical evaluation methods and tools, and perform a formative and summative clinical evaluation. Also, workload adjustment of the nursing trainers needs revision. Therefore, despite using traditional and sometimes limited evaluation methods for assessing nursing students, a co mprehensive and appropriate evaluation of nursing students’ clinical competencies seems necessary. PMID:24554959
Crystallography of biological fluid as a method for evaluating its physicochemical characteristics.
Martusevich, A K; Kamakin, N F
2007-03-01
Using an integral qualitative and quantitative approach to the studies of initiation of the biological material crystallogenesis, we showed in experiments with normal human saliva that the external characteristics of biological fluid (pH, osmolality, and environmental temperature) determine the results of crystallization (tesigraphic facies). The main external (macroenvironment) and inner (microenvironment) factors of biological fluid crystal formation, determining specific features of the tesigraphic facies, were distinguished and classified. The informative value of differential analysis of biomaterial properties by means of modulating the environmental conditions is established.
Large-scale galaxy flow from a non-gravitational impulse
NASA Technical Reports Server (NTRS)
Hogan, Craig J.; Kaiser, Nick
1989-01-01
A theory is presented describing linear perturbations of an expanding universe containing multiple, independently perturbed, collisionless, gravitationally coupled constituents. Solutions are found in the limit where one initially unperturbed component dominates the total density. The theory is applied to perturbations generated by a nongravitational process in one or more of the light components, as would occur in explosive or radiation-pressure-instability theories of galaxy formation. The apparent dynamical density parameter and correlations between density and velocity amplitude for various populations, are evaluated as a function of cosmic scale factor.
Conceptual models of the formation of acid-rock drainage at road cuts in Tennessee
Bradley, Michael W.; Worland, Scott; Byl, Tom
2015-01-01
Pyrite and other minerals containing sulfur and trace metals occur in several rock formations throughout Middle and East Tennessee. Pyrite (FeS2) weathers in the presence of oxygen and water to form iron hydroxides and sulfuric acid. The weathering and interaction of the acid on the rocks and other minerals at road cuts can result in drainage with low pH (< 4) and high concentrations of trace metals. Acid-rock drainage can cause environmental problems and damage transportation infrastructure. The formation and remediation of acid-drainage from roads cuts has not been researched as thoroughly as acid-mine drainage. The U.S Geological Survey, in cooperation with the Tennessee Department of Transportation, is conducting an investigation to better understand the geologic, hydrologic, and biogeochemical factors that control acid formation at road cuts. Road cuts with the potential for acid-rock drainage were identifed and evaluated in Middle and East Tennessee. The pyrite-bearing formations evaluated were the Chattanooga Shale (Devonian black shale), the Fentress Formation (coal-bearing), and the Precambrian Anakeesta Formation and similar Precambrian rocks. Conceptual models of the formation and transport of acid-rock drainage (ARD) from road cuts were developed based on the results of a literature review, site reconnaissance, and the initial rock and water sampling. The formation of ARD requires a combination of hydrologic, geochemical, and microbial interactions which affect drainage from the site, acidity of the water, and trace metal concentrations. The basic modes of ARD formation from road cuts are; 1 - seeps and springs from pyrite-bearing formations and 2 - runoff over the face of a road cut in a pyrite-bearing formation. Depending on site conditions at road cuts, the basic modes of ARD formation can be altered and the additional modes of ARD formation are; 3 - runoff over and through piles of pyrite-bearing material, either from construction or breakdown material weathered from shale, and 4 - the deposition of secondary-sulfate minerals can store trace metals and, during rainfall, result in increased acidity and higher concentrations of trace metals in storm runoff. Understanding the factors that control ARD formation and transport are key to addressing the problems associated with the movement of ARD from the road cuts to the environment. The investigation will provide the Tennessee Department of Transportation with a regional characterization of ARD and provide insights into the geochemical and biochemical attributes for the control and remediation of ARD from road cuts.
Xing, Yang; Ge, Yuqing; Liu, Chanjuan; Zhang, Xiaobiao; Jiang, Jianhai; Wei, Yuanyan
2016-06-14
Glioma-initiating cells possess tumor-initiating potential and are relatively resistant to conventional chemotherapy and irradiation. Therefore, their elimination is an essential factor for the development of efficient therapy. Here, we report that endoplasmic reticulum (ER) stress inducer tunicamycin inhibits glioma-initiating cell self-renewal as determined by neurosphere formation assay. Moreover, tunicamycin decreases the efficiency of glioma-initiating cell to initiate tumor formation. Although tunicamycin induces glioma-initiating cell apoptosis, apoptosis inhibitor z-VAD-fmk only partly abrogates the reduction in glioma-initiating cell self-renewal induced by tunicamycin. Indeed, tunicamycin reduces the expression of self-renewal regulator Sox2 at translation level. Overexpression of Sox2 obviously abrogates the reduction in glioma-initiating cell self-renewal induced by tunicamycin. Taken together, tunicamycin suppresses the self-renewal and tumorigenic potential of glioma-initiating cell partly through reducing Sox2 translation. This finding provides a cue to potential effective treatment of glioblastoma through controlling stem cells.
Astronomy in the Initial Formation of Sciences Teachers
NASA Astrophysics Data System (ADS)
Costa, Samuel; Euzébio, Geison João; Damasio, Felipe
2016-12-01
Although astronomy is considered one of the older sciences of mankind, its teaching in basic education is facing problems. It is the school responsibility the dissemination of correct scientific concepts, including those related to Astronomy. This study was conducted at the Federal Institute of Education, Science and Technology of Santa Catarina, Campus Araranguá. In this article, we aimed to present the activities developed to help the formation of teachers, training undergraduate students in Natural Sciences with specialization in Physics to contribute to the dissemination and improvement of the teaching-learning of Astronomy. This paper presents the process and results of the evaluation of that training program. Analyses of the activity from the perspective of the participants are indicated and additional considerations are made regarding its use as a resource for teaching Astronomy and for teacher training.
A Comparison of Formative and Summative Evaluation.
ERIC Educational Resources Information Center
Belenski, Mary Jo
Formative and summative evaluations in education are compared, and appropriate uses of these methods in program evaluation are discussed. The main purpose of formative evaluation is to determine a level of mastery of a learning task, along with discovering any part of the task that was not mastered. In other words, formative evaluation focuses the…
NASA Astrophysics Data System (ADS)
Liu, Tengyu; Huang, Dan Dan; Li, Zijun; Liu, Qianyun; Chan, ManNin; Chan, Chak K.
2018-04-01
The formation of secondary organic aerosol (SOA) has been widely studied in the presence of dry seed particles at low relative humidity (RH). At higher RH, initially dry seed particles can exist as wet particles due to water uptake by the seeds as well as the SOA. Here, we investigated the formation of SOA from the photooxidation of toluene using an oxidation flow reactor in the absence of NOx under a range of OH exposures on initially wet or dry ammonium sulfate (AS) seed particles at an RH of 68 %. The ratio of the SOA yield on wet AS seeds to that on dry AS seeds, the relative SOA yield, decreased from 1.31 ± 0.02 at an OH exposure of 4.66 × 1010 molecules cm-3 s to 1.01 ± 0.01 at an OH exposure of 5.28 × 1011 molecules cm-3 s. This decrease may be due to the early deliquescence of initially dry AS seeds after being coated by highly oxidized toluene-derived SOA. SOA formation lowered the deliquescence RH of AS and resulted in the uptake of water by both AS and SOA. Hence the initially dry AS seeds contained aerosol liquid water (ALW) soon after SOA formed, and the SOA yield and ALW approached those of the initially wet AS seeds as OH exposure and ALW increased, especially at high OH exposure. However, a higher oxidation state of the SOA on initially wet AS seeds than that on dry AS seeds was observed at all levels of OH exposure. The difference in mass fractions of m / z 29, 43 and 44 of SOA mass spectra, obtained using an aerosol mass spectrometer (AMS), indicated that SOA formed on initially wet seeds may be enriched in earlier-generation products containing carbonyl functional groups at low OH exposures and later-generation products containing acidic functional groups at high exposures. Our results suggest that inorganic dry seeds become at least partially deliquesced particles during SOA formation and hence that ALW is inevitably involved in the SOA formation at moderate RH. More laboratory experiments conducted with a wide variety of SOA precursors and inorganic seeds under different NOx and RH conditions are warranted.
Evaluation of a community health representative program among the Cree of northern Quebec.
Lavallée, C; James, C A; Robinson, E J
1991-01-01
The James Bay Cree Community Health Representative (CHR) program was implemented in 1984 to train persons from the Cree population of northern Quebec to act as health care advocates and educators, as intermediaries between the Cree population, health services and local organizations, and as participants in assessing health needs. A formative evaluation was initiated which included quantitative analysis of the daily tasks of CHRs and a qualitative component based on documentary research, observation and semi-structured interviews. The evaluation revealed that CHRs actively participated in the ongoing community health programs mainly through health education; the people interviewed showed a high level of satisfaction. However, direct supervision, sufficient continuing education for the CHRs and better integration into health care teams are long-term goals which need to be emphasized in the program.
Polymer-cement interactions towards improved wellbore cement fracture sealants
NASA Astrophysics Data System (ADS)
Beckingham, B. S.; Iloejesi, C.; Minkler, M. J.; Schindler, A. K.; Beckingham, L. E.
2017-12-01
Carbon capture, utilization, and storage (CCUS) in deep geologic formations is a promising means of reducing point source emissions of CO2. In these systems, CO2 is captured at the source and then injected to be utilized (eg. in enhanced oil recovery or as a working fluid in enhanced geothermal energy plants) or stored in geologic formations such as depleted oil and gas reservoirs or saline aquifers. While CCUS in subsurface systems could aid in reducing atmospheric CO2 emissions, the potential for CO2 leakage from these systems to overlying formations remains a major limitation and poses a significant risk to the security of injected CO2. Thus, improved materials for both initial wellbore isolation and repairing leakage pathways that develop over time are sought. One approach for the repair of cement fractures in wellbore (and other) systems is the injection of polymer materials into the fracture with a subsequent environmentally dependent (temperature, pressure, pH, etc.) densification or solidification. Here, we aim to investigate novel polymer materials for use to repair leaking wellbores in the context of CCUS. We synthesize and fully characterize a series of novel polymer materials and utilize a suite of analysis techniques to examine polymer-cement interactions at a range of conditions (namely temperature, pressure and pH). Initial findings will be leveraged to design novel polymer materials for further evaluation in polymer-cement composite cores, cement fracture healing, and the aging behavior of healed cements.
Lipid-modifying enzymes in oat and faba bean.
Yang, Zhen; Piironen, Vieno; Lampi, Anna-Maija
2017-10-01
The aim was to study lipase, lipoxygenase (LOX) and peroxygenase (POX) activities in oat and faba bean samples to be able to evaluate their potential in formation of lipid-derived off-flavours. Lipase and LOX activities were measured by spectroscopy, and POX activities via the formation of epoxides. An ultra-high performance liquid chromatography method was developed to study the formation of fatty acid epoxides. The epoxides of esters were measured by gas chromatography. Mass spectroscopy was used to verify the identity of the epoxides. Both oat and faba bean possessed high lipase activities. In faba bean, LOX catalysed the formation of hydroperoxides, whose break-down products are the likely cause of off-flavours. Since oat had low LOX activity, autoxidation is needed to initiate lipid oxidation. Oat had high POX activity, which is able to convert hydroperoxides to epoxy and hydroxy fatty acids that could contribute significantly to off-flavours. POX activity in the faba bean was low. Thus, in faba bean volatile lipid oxidation products could rapidly be formed by LOX, whereas in oat reactions are slower due to the need of autoxidation prior to further reactions. Copyright © 2017 Elsevier Ltd. All rights reserved.
A specific role of iron in promoting meristematic cell division during adventitious root formation.
Hilo, Alexander; Shahinnia, Fahimeh; Druege, Uwe; Franken, Philipp; Melzer, Michael; Rutten, Twan; von Wirén, Nicolaus; Hajirezaei, Mohammad-Reza
2017-07-10
Adventitious root (AR) formation is characterized by a sequence of physiological and morphological processes and determined by external factors, including mineral nutrition, the impacts of which remain largely elusive. Morphological and anatomical evaluation of the effects of mineral elements on AR formation in leafy cuttings of Petunia hybrida revealed a striking stimulation by iron (Fe) and a promotive action of ammonium (NH4+). The optimal application period for these nutrients corresponded to early division of meristematic cells in the rooting zone and coincided with increased transcript levels of mitotic cyclins. Fe-localization studies revealed an enhanced allocation of Fe to the nuclei of meristematic cells in AR initials. NH4+ supply promoted AR formation to a lesser extent, most likely by favoring the availability of Fe. We conclude that Fe acts locally by promoting cell division in the meristematic cells of AR primordia. These results highlight a specific biological function of Fe in AR development and point to an unexploited importance of Fe for the vegetative propagation of plants from cuttings. © The Author 2017. Published by Oxford University Press on behalf of the Society for Experimental Biology.
Hiligsmann, Mickaël; Cooper, Cyrus; Guillemin, Francis; Hochberg, Marc C; Tugwell, Peter; Arden, Nigel; Berenbaum, Francis; Boers, Maarten; Boonen, Annelies; Branco, Jaime C; Maria-Luisa, Brandi; Bruyère, Olivier; Gasparik, Andrea; Kanis, John A; Kvien, Tore K; Martel-Pelletier, Johanne; Pelletier, Jean-Pierre; Pinedo-Villanueva, Rafael; Pinto, Daniel; Reiter-Niesert, Susanne; Rizzoli, René; Rovati, Lucio C; Severens, Johan L; Silverman, Stuart; Reginster, Jean-Yves
2014-12-01
General recommendations for a reference case for economic studies in rheumatic diseases were published in 2002 in an initiative to improve the comparability of cost-effectiveness studies in the field. Since then, economic evaluations in osteoarthritis (OA) continue to show considerable heterogeneity in methodological approach. To develop a reference case specific for economic studies in OA, including the standard optimal care, with which to judge new pharmacologic and non-pharmacologic interventions. Four subgroups of an ESCEO expert working group on economic assessments (13 experts representing diverse aspects of clinical research and/or economic evaluations) were charged with producing lists of recommendations that would potentially improve the comparability of economic analyses in OA: outcome measures, comparators, costs and methodology. These proposals were discussed and refined during a face-to-face meeting in 2013. They are presented here in the format of the recommendations of the recently published Consolidated Health Economic Evaluation Reporting Standards (CHEERS) statement, so that an initiative on economic analysis methodology might be consolidated with an initiative on reporting standards. Overall, three distinct reference cases are proposed, one for each hand, knee and hip OA; with diagnostic variations in the first two, giving rise to different treatment options: interphalangeal or thumb-based disease for hand OA and the presence or absence of joint malalignment for knee OA. A set of management strategies is proposed, which should be further evaluated to help establish a consensus on the "standard optimal care" in each proposed reference case. The recommendations on outcome measures, cost itemisation and methodological approaches are also provided. The ESCEO group proposes a set of disease-specific recommendations on the conduct and reporting of economic evaluations in OA that could help the standardisation and comparability of studies that evaluate therapeutic strategies of OA in terms of costs and effectiveness. Copyright © 2014 The Authors. Published by Elsevier Inc. All rights reserved.
Powder compression mechanics of spray-dried lactose nanocomposites.
Hellrup, Joel; Nordström, Josefina; Mahlin, Denny
2017-02-25
The aim of this study was to investigate the structural impact of the nanofiller incorporation on the powder compression mechanics of spray-dried lactose. The lactose was co-spray-dried with three different nanofillers, that is, cellulose nanocrystals, sodium montmorillonite and fumed silica, which led to lower micron-sized nanocomposite particles with varying structure and morphology. The powder compression mechanics of the nanocomposites and physical mixtures of the neat spray-dried components were evaluated by a rational evaluation method with compression analysis as a tool, using the Kawakita equation and the Shapiro-Konopicky-Heckel equation. Particle rearrangement dominated the initial compression profiles due to the small particle size of the materials. The strong contribution of particle rearrangement in the materials with fumed silica continued throughout the whole compression profile, which prohibited an in-depth material characterization. However, the lactose/cellulose nanocrystals and the lactose/sodium montmorillonite nanocomposites demonstrated high yield pressure compared with the physical mixtures indicating increased particle hardness upon composite formation. This increase has likely to do with a reinforcement of the nanocomposite particles by skeleton formation of the nanoparticles. In summary, the rational evaluation of mechanical properties done by applying powder compression analysis proved to be a valuable tool for mechanical evaluation for this type of spray-dried composite materials, unless they demonstrate particle rearrangement throughout the whole compression profile. Copyright © 2016 Elsevier B.V. All rights reserved.
NO2-initiated multiphase oxidation of SO2 by O2 on CaCO3 particles
NASA Astrophysics Data System (ADS)
Yu, Ting; Zhao, Defeng; Song, Xiaojuan; Zhu, Tong
2018-05-01
The reaction of SO2 with NO2 on the surface of aerosol particles has been suggested to be important in sulfate formation during severe air pollution episodes in China. However, we found that the direct oxidation of SO2 by NO2 was slow and might not be the main reason for sulfate formation in ambient air. In this study, we investigated the multiphase reaction of SO2 with an O2 / NO2 mixture on single CaCO3 particles using Micro-Raman spectroscopy. The reaction converted the CaCO3 particle to a Ca(NO3)2 droplet, with CaSO4 ⚫ 2H2O solid particles embedded in it, which constituted a significant fraction of the droplet volume at the end of the reaction. The reactive uptake coefficient of SO2 for sulfate formation was on the order of 10-5, which was higher than that for the multiphase reaction of SO2 directly with NO2 by 2-3 orders of magnitude. According to our observations and the literature, we found that in the multiphase reaction of SO2 with the O2 / NO2 mixture, O2 was the main oxidant of SO2 and was necessary for radical chain propagation. NO2 acted as the initiator of radical formation, but not as the main oxidant. The synergy of NO2 and O2 resulted in much faster sulfate formation than the sum of the reaction rates with NO2 and with O2 alone. We estimated that the multiphase oxidation of SO2 by O2 initiated by NO2 could be an important source of sulfate and a sink of SO2, based on the calculated lifetime of SO2 regarding the loss through the multiphase reaction versus the loss through the gas-phase reaction with OH radicals. Parameterization of the reactive uptake coefficient of the reaction observed in our laboratory for further model simulation is needed, as well as an integrated assessment based on field observations, laboratory study results, and model simulations to evaluate the importance of the reaction in ambient air during severe air pollution episodes, especially in China.
Influence of initial seed distribution on the pattern formation of the phase field crystals
NASA Astrophysics Data System (ADS)
Starodumov, Ilya; Galenko, Peter; Kropotin, Nikolai; Alexandrov, Dmitri V.
2017-11-01
The process of crystal growth can be expressed as a transition of atomic structure to a finally stable state or to a metastable state. In the Phase Field Crystal Model (PFC-model) these states are described by regular distributions of the atomic density. Getting the system into any metastable condition may be caused by the peculiarities of the computational domain, initial and boundary conditions. However, an important factor in the formation of the crystal structure can be the initial disturbance. In the report we show how different types of initial disturbance can change the finally stable state of crystal structure in equilibrium.
Methodology of ETV Formative Evaluation.
ERIC Educational Resources Information Center
Duby, Aliza
Formative evaluation is discussed as it relates to educational television (ETV). Formative evaluation, used to improve a project during its development, is especially valuable in the production of television programs. Methods useful in the formative evaluation of ETV are: (1) try-out studies; (2) learner verification and revision; (3)…
Trust in the workplace: factors affecting trust formation between team members.
Spector, Michele D; Jones, Gwen E
2004-06-01
The authors used survey data from 127 professional-level employees working in 8 industries to assess the effects of respondent's trusting stance and (a) the trustee's organization membership (internal or external), (b) the hierarchical relationship (supervisor or peer), and (c) the gender of the trustee, on initial trust level for a new project team member. The authors found that trusting stance was positively related to initial trust level. The authors also found an interaction effect between respondent gender and trustee gender on initial trust. Specifically, male initial trust level was higher for a new male team member and lower for a new female team member. The present study provided additional understanding of the formation of initial trust levels and its importance for team functioning.
Explosive Model Tarantula V1/JWL++ Calibration of LX-17: #2
DOE Office of Scientific and Technical Information (OSTI.GOV)
Souers, P C; Vitello, P
2009-05-01
Tarantula V1 is a kinetic package for reactive flow codes that seeks to describe initiation, failure, dead zones and detonation simultaneously. The most important parameter is P1, the pressure between the initiation and failure regions. Both dead zone formation and failure can be largely controlled with this knob. However, V1 does failure with low settings and dead zones with higher settings, so that it cannot fulfill its purpose in the current format. To this end, V2 is under test. The derivation of the initiation threshold P0 is discussed. The derivation of the initiation pressure-tau curve as an output of Tarantulamore » shows that the initiation package is sound. A desensitization package is also considered.« less
Mazroui, Rachid; Sukarieh, Rami; Bordeleau, Marie-Eve; Kaufman, Randal J; Northcote, Peter; Tanaka, Junichi; Gallouzi, Imed; Pelletier, Jerry
2006-10-01
Cytoplasmic aggregates known as stress granules (SGs) arise as a consequence of cellular stress and contain stalled translation preinitiation complexes. These foci are thought to serve as sites of mRNA storage or triage during the cell stress response. SG formation has been shown to require induction of eukaryotic initiation factor (eIF)2alpha phosphorylation. Herein, we investigate the potential role of other initiation factors in this process and demonstrate that interfering with eIF4A activity, an RNA helicase required for the ribosome recruitment phase of translation initiation, induces SG formation and that this event is not dependent on eIF2alpha phosphorylation. We also show that inhibition of eIF4A activity does not impair the ability of eIF2alpha to be phosphorylated under stress conditions. Furthermore, we observed SG assembly upon inhibition of cap-dependent translation after poliovirus infection. We propose that SG modeling can occur via both eIF2alpha phosphorylation-dependent and -independent pathways that target translation initiation.
Mazroui, Rachid; Sukarieh, Rami; Bordeleau, Marie-Eve; Kaufman, Randal J.; Northcote, Peter; Tanaka, Junichi; Gallouzi, Imed
2006-01-01
Cytoplasmic aggregates known as stress granules (SGs) arise as a consequence of cellular stress and contain stalled translation preinitiation complexes. These foci are thought to serve as sites of mRNA storage or triage during the cell stress response. SG formation has been shown to require induction of eukaryotic initiation factor (eIF)2α phosphorylation. Herein, we investigate the potential role of other initiation factors in this process and demonstrate that interfering with eIF4A activity, an RNA helicase required for the ribosome recruitment phase of translation initiation, induces SG formation and that this event is not dependent on eIF2α phosphorylation. We also show that inhibition of eIF4A activity does not impair the ability of eIF2α to be phosphorylated under stress conditions. Furthermore, we observed SG assembly upon inhibition of cap-dependent translation after poliovirus infection. We propose that SG modeling can occur via both eIF2α phosphorylation-dependent and -independent pathways that target translation initiation. PMID:16870703
Children's Initial Sleep-Associated Changes in Motor Skill Are Unrelated to Long-Term Skill Levels
ERIC Educational Resources Information Center
Zinke, Katharina; Wilhelm, Ines; Bayramoglu, Müge; Klein, Susanne; Born, Jan
2017-01-01
Sleep is considered to support the formation of skill memory. In juvenile but not adult song birds learning a tutor's song, a stronger initial deterioration of song performance over night-sleep predicts better song performance in the long run. This and similar observations have stimulated the view of sleep supporting skill formation during…
NASA Technical Reports Server (NTRS)
Broeze, R. J.; Pope, D. H.
1978-01-01
The inhibition of translation which is observed after shifting Escherichia coli to low temperature was investigated. 70 S ribosomes were isolated from E. coli 8 hours after a shift to 5 C synthesized protein in the absence of added mRNA (i.e., endogenous protein synthesis by 70 S monosomes) at a rate which was three times greater than the rate of endogenous protein synthesis by 70 S ribosomes which were isolated at the time of the shift to 5 C. Calculations based on the rates of endogenous protein synthesis and polyphenylalanine synthesis indicate that 70 S monosomes comprise only 0.1% of the total E. coli 70 S ribosome population after 8 hours at 5 c. Experiments designed to test initiation complex formation on ApUpG or formaldehyde treated MS-2 viral RNA demonstrated that, although the rate of formation of 30 S initiation complexes was not inhibited, the rate of formation of active 70 S initiation complexes, able to react with puromycin, was inhibited to a great extent at 5 C. A model depicting the effects of low temperature on the E. coli translation system is proposed.
NASA Astrophysics Data System (ADS)
Tkachenko, Ekaterina
2017-11-01
This work presents a hypothesis about the mechanism of bromine activation during polar boundary layer ozone depletion events (ODEs) as well as the mechanism of aerosol formation from the frost flowers. The author suggests that ODEs may be initiated by the electric-field gradients created at the sharp tips of ice formations as a result of the combined effect of various environmental conditions. According to the author's estimates, these electric-field gradients may be sufficient for the onset of point or corona discharges followed by generation of high local concentrations of the reactive oxygen species and initiation of free-radical and redox reactions. This process may be responsible for the formation of seed bromine which then undergoes further amplification by HOBr-driven bromine explosion. The proposed hypothesis may explain a variety of environmental conditions and substrates as well as poor reproducibility of ODE initiation observed by researchers in the field. According to the author's estimates, high wind can generate sufficient conditions for overcoming the Rayleigh limit and thus can initiate ;spraying; of charged aerosol nanoparticles. These charged aerosol nanoparticles can provoke formation of free radicals, turning the ODE on. One can also envision a possible emission of halogen ion as a result of the ;electrospray; process analogous to that of electrospray ionization mass-spectrometry.
Randazzo, James; Zhang, Peng; Makita, Jun; Blessing, Karen; Kador, Peter F.
2011-01-01
Background Age-related cataract is a worldwide health care problem whose progression has been linked to oxidative stress and the accumulation of redox-active metals. Since there is no specific animal model for human age-related cataract, multiple animal models must be used to evaluate potential therapies that may delay and/or prevent cataract formation. Methods/Principal Findings Proof of concept studies were conducted to evaluate 4-(5-hydroxypyrimidin-2-yl)-N,N-dimethyl-3,5-dioxopiperazine-1-sulfonamide (compound 4) and 4-(5-hydroxy-4,6-dimethoxypyrimidin-2-yl)-N,N-dimethyl-3,5-dioxopiperazine-1-sulfonamide (compound 8), multi-functional antioxidants that can independently chelate redox metals and quench free radicals, on their ability to delay the progression of diabetic “sugar” cataracts and gamma radiation-induced cataracts. Prior to 15 Gy of whole head irradiation, select groups of Long Evans rats received either diet containing compound 4 or 8, or a single i.p. injection of panthethine, a radioprotective agent. Compared to untreated, irradiated rats, treatment with pantethine, 4 and 8 delayed initial lens changes by 4, 47, and 38 days, respectively, and the average formation of posterior subcapsular opacities by 23, 53 and 58 days, respectively. In the second study, select groups of diabetic Sprague Dawley rats were administered chow containing compounds 4, 8 or the aldose reductase inhibitor AL1576. As anticipated, treatment with AL1576 prevented cataract by inhibiting sorbitol formation in the lens. However, compared to untreated rats, compounds 4 and 8 delayed vacuole formation by 20 days and 12 days, respectively, and cortical cataract formation by 8 and 3 days, respectively, without reducing lenticular sorbitol. Using in vitro lens culture in 30 mM xylose to model diabetic “sugar” cataract formation, western blots confirmed that multi-functional antioxidants reduced endoplasmic reticulum stress. Conclusions/Significance Multi-functional antioxidants delayed cataract formation in two diverse rat models. These studies provide a proof of concept that a general cataract treatment focused on reducing oxidative stress instead of a specific mechanism of cataractogenesis can be developed. PMID:21541328
Qualitative and quantitative evaluation of avian demineralized bone matrix in heterotopic beds.
Reza Sanaei, M; Abu, Jalila; Nazari, Mojgan; A B, Mohd Zuki; Allaudin, Zeenathul N
2013-11-01
To evaluate the osteogenic potential of avian demineralized bone matrix (DBM) in the context of implant geometry. Experimental. Rock pigeons (n = 24). Tubular and chipped forms of DBM were prepared by acid demineralization of long bones from healthy allogeneic donors and implanted bilaterally into the pectoral region of 24 pigeons. After euthanasia at 1, 4, 6, 8, 10, and 12 weeks, explants were evaluated histologically and compared by means of quantitative (bone area) and semi quantitative measures (scores). All explants had new bone at retrieval with the exception of tubular implants at the end of week 1. The most reactive part in both implants was the interior region between the periosteal and endosteal surfaces followed by the area at the implant-muscle interface. Quantitative measurements demonstrated a significantly (P = .012) greater percentage of new bone formation induced by tubular implants (80.28 ± 8.94) compared with chip implants (57.64 ± 3.12). There was minimal inflammation. Avian DBM initiates heterotopic bone formation in allogeneic recipients with low grades of immunogenicity. Implant geometry affects this phenomenon as osteoconduction appeared to augment the magnitude of the effects in larger tubular implants. © Copyright 2013 by The American College of Veterinary Surgeons.
Olson, Jonathan R; McCarthy, Kimberly J; Perkins, Daniel F; Borden, Lynne M
2018-04-01
The Children, Youth, and Families At-Risk (CYFAR) initiative provides funding and technical support for local community-based programs designed to promote positive outcomes among vulnerable populations. In 2013, CYFAR implemented significant changes in the way it provides technical assistance (TA) to grantees. These changes included introducing a new TA model in which trained coaches provide proactive support that is tailored to individual CYFAR projects. The purpose of this paper is to describe the evolution of this TA model and present preliminary findings from a formative evaluation. CYFAR Principal Investigators (PIs) were invited to respond to online surveys in 2015 and 2016. The surveys were designed to assess PI attitudes towards the nature and quality of support that they receive from their coaches. CYFAR PIs reported that their coaches have incorporated a range of coaching skills and techniques into their work. PIs have generally positive attitudes towards their coaches, and these attitudes have become more positive over time. Results suggest that CYFAR PIs have been generally supportive of the new TA system. Factors that may have facilitated support include a strong emphasis on team-building and the provision of specific resources that support program design, implementation, and evaluation. Copyright © 2017 Elsevier Ltd. All rights reserved.
Evaluation of the healing activity of therapeutic clay in rat skin wounds.
Dário, Giordana Maciel; da Silva, Geovana Gomes; Gonçalves, Davi Ludvig; Silveira, Paulo; Junior, Adilson Teixeira; Angioletto, Elidio; Bernardin, Adriano Michael
2014-10-01
The use of clays for therapeutic practice is widespread in almost all regions of the world. In this study the physicochemical and microbiological healing characteristics of a clay from Ocara, Brazil, popularly used for therapeutic uses, were analyzed. The presence of Ca, Mg, Al, Fe, and Si was observed, which initially indicated that the clay had potential for therapeutic use. The average particle size of the clay (26.3 μm) can induce the microcirculation of the skin and the XRD analysis shows that the clay is formed by kaolinite and illite, a swelling clay. During the microbiological evaluation there was the need to sterilize the clay for later incorporation into the pharmaceutical formula. The accelerated stability test at 50°C for 3 months has showed that the pharmaceutical formula remained stable with a shelf life of two years. After the stability test the wound-healing capacity of the formulation in rats was evaluated. It was observed that the treatment made with the formulation containing the Ocara clay showed the best results since the formula allowed greater formation of collagen fibers and consequent regeneration of the deep dermis after seven days of treatment and reepithelialization and continuous formation of granulation tissue at the 14th day. Copyright © 2014 Elsevier B.V. All rights reserved.
Physician performance feedback in a Canadian academic center.
Garvin, Dennis; Worthington, James; McGuire, Shaun; Burgetz, Stephanie; Forster, Alan J; Patey, Andrea; Gerin-Lajoie, Caroline; Turnbull, Jeffrey; Roth, Virginia
2017-10-02
Purpose This paper aims at the implementation and early evaluation of a comprehensive, formative annual physician performance feedback process in a large academic health-care organization. Design/methodology/approach A mixed methods approach was used to introduce a formative feedback process to provide physicians with comprehensive feedback on performance and to support professional development. This initiative responded to organization-wide engagement surveys through which physicians identified effective performance feedback as a priority. In 2013, physicians primarily affiliated with the organization participated in a performance feedback process, and physician satisfaction and participant perceptions were explored through participant survey responses and physician leader focus groups. Training was required for physician leaders prior to conducting performance feedback discussions. Findings This process was completed by 98 per cent of eligible physicians, and 30 per cent completed an evaluation survey. While physicians endorsed the concept of a formative feedback process, process improvement opportunities were identified. Qualitative analysis revealed the following process improvement themes: simplify the tool, ensure leaders follow process, eliminate redundancies in data collection (through academic or licensing requirements) and provide objective quality metrics. Following physician leader training on performance feedback, 98 per cent of leaders who completed an evaluation questionnaire agreed or strongly agreed that the performance feedback process was useful and that training objectives were met. Originality/value This paper introduces a physician performance feedback model, leadership training approach and first-year implementation outcomes. The results of this study will be useful to health administrators and physician leaders interested in implementing physician performance feedback or improving physician engagement.
Bazzi, Angela R; Mogro-Wilson, Cristina; Negi, Nalini Junko; Gonzalez, Jennifer M Reingle; Cano, Miguel Ángel; Castro, Yessenia; Cepeda, Alice
2017-01-01
Hispanics are disproportionately affected by substance use and related health harms yet remain underrepresented across scientific disciplines focused on researching and addressing these issues. An interdisciplinary network of scientists committed to fostering the development of social and biomedical researchers focused on Hispanic substance use and health disparities developed innovative mentoring and career development activities. We conducted a formative evaluation study using anonymous membership and conference feedback data to describe specific mentoring and career development activities developed within the national network. Successful mentoring initiatives and career development activities were infused with cultural and community values supportive of professional integration and persistence. Mentoring initially occurred within an annual national conference and was then sustained throughout the year through formal training programs and informal mentoring networks. Although rigorous evaluation is needed to determine the success of these strategies in fostering long-term career development among scientists conducting Hispanic health and substance use research, this innovative model may hold promise for other groups committed to promoting career development and professional integration and persistence for minority (and non-minority) scientists committed to addressing health disparities.
PREVENT: a program of the National Training Initiative on Injury and Violence Prevention.
Runyan, Carol W; Gunther-Mohr, Carol; Orton, Stephen; Umble, Karl; Martin, Sandra L; Coyne-Beasley, Tamera
2005-12-01
Training practitioners to use evidence-based approaches to the primary prevention of violence is challenging as a result of the dearth of well-evaluated intervention programs and the lack of familiarity of some practitioners in drawing critically on existing literature. An element of the National Training Initiative in Injury and Violence Prevention, the PREVENT (Preventing Violence Through Education, Networking, and Technical Assistance) program began in late 2003 to train practitioners to address multiple types of violence by encouraging more widespread use of evidence-based approaches to primary prevention. It is intended to reach practitioners involved in addressing violence against women, sexual violence, child maltreatment, youth violence, and suicide in varied community settings. The program uses a combination of varied types of face-to-face training and distance learning coupled with opportunities for networking and technical assistance. Ultimately the program intends to stimulate and facilitate changes in individual, organizational, and cultural awareness and practices fostering primary prevention of violence. The project employs formative, process, and impact evaluation techniques aimed at improving delivery of the training as well as tracking changes in individual and organizations.
Lassnig, R; Hollerer, M; Striedinger, B; Fian, A; Stadlober, B; Winkler, A
2015-11-01
In this work we present in situ electrical and surface analytical, as well as ex situ atomic force microscopy (AFM) studies on temperature and surface condition induced pentacene layer growth modifications, leading to the selection of optimized deposition conditions and entailing performance improvements. We prepared p ++ -silicon/silicon dioxide bottom-gate, gold bottom-contact transistor samples and evaluated the pentacene layer growth for three different surface conditions (sputtered, sputtered + carbon and unsputtered + carbon) at sample temperatures during deposition of 200 K, 300 K and 350 K. The AFM investigations focused on the gold contacts, the silicon dioxide channel region and the highly critical transition area. Evaluations of coverage dependent saturation mobilities, threshold voltages and corresponding AFM analysis were able to confirm that the first 3-4 full monolayers contribute to the majority of charge transport within the channel region. At high temperatures and on sputtered surfaces uniform layer formation in the contact-channel transition area is limited by dewetting, leading to the formation of trenches and the partial development of double layer islands within the channel region instead of full wetting layers. By combining the advantages of an initial high temperature deposition (well-ordered islands in the channel) and a subsequent low temperature deposition (continuous film formation for low contact resistance) we were able to prepare very thin (8 ML) pentacene transistors of comparably high mobility.
Lassnig, R.; Hollerer, M.; Striedinger, B.; Fian, A.; Stadlober, B.; Winkler, A.
2015-01-01
In this work we present in situ electrical and surface analytical, as well as ex situ atomic force microscopy (AFM) studies on temperature and surface condition induced pentacene layer growth modifications, leading to the selection of optimized deposition conditions and entailing performance improvements. We prepared p++-silicon/silicon dioxide bottom-gate, gold bottom-contact transistor samples and evaluated the pentacene layer growth for three different surface conditions (sputtered, sputtered + carbon and unsputtered + carbon) at sample temperatures during deposition of 200 K, 300 K and 350 K. The AFM investigations focused on the gold contacts, the silicon dioxide channel region and the highly critical transition area. Evaluations of coverage dependent saturation mobilities, threshold voltages and corresponding AFM analysis were able to confirm that the first 3–4 full monolayers contribute to the majority of charge transport within the channel region. At high temperatures and on sputtered surfaces uniform layer formation in the contact–channel transition area is limited by dewetting, leading to the formation of trenches and the partial development of double layer islands within the channel region instead of full wetting layers. By combining the advantages of an initial high temperature deposition (well-ordered islands in the channel) and a subsequent low temperature deposition (continuous film formation for low contact resistance) we were able to prepare very thin (8 ML) pentacene transistors of comparably high mobility. PMID:26543442
Influence of amorphous structure on polymorphism in vanadia
DOE Office of Scientific and Technical Information (OSTI.GOV)
Stone, Kevin H.; Schelhas, Laura T.; Garten, Lauren M.
Normally we think of the glassy state as a single phase and therefore crystallization from chemically identical amorphous precursors should be identical. Here we show that the local structure of an amorphous precursor is distinct depending on the initial deposition conditions, resulting in significant differences in the final state material. Using grazing incidence total x-ray scattering, we have determined the local structure in amorphous thin films of vanadium oxide grown under different conditions using pulsed laser deposition (PLD). Here we show that the subsequent crystallization of films deposited using different initial PLD conditions result in the formation of different polymorphsmore » of VO 2. Ultimately this suggests the possibility of controlling the formation of metastable polymorphs by tuning the initial amorphous structure to different formation pathways.« less
Influence of amorphous structure on polymorphism in vanadia
Stone, Kevin H.; Schelhas, Laura T.; Garten, Lauren M.; ...
2016-07-13
Normally we think of the glassy state as a single phase and therefore crystallization from chemically identical amorphous precursors should be identical. Here we show that the local structure of an amorphous precursor is distinct depending on the initial deposition conditions, resulting in significant differences in the final state material. Using grazing incidence total x-ray scattering, we have determined the local structure in amorphous thin films of vanadium oxide grown under different conditions using pulsed laser deposition (PLD). Here we show that the subsequent crystallization of films deposited using different initial PLD conditions result in the formation of different polymorphsmore » of VO 2. Ultimately this suggests the possibility of controlling the formation of metastable polymorphs by tuning the initial amorphous structure to different formation pathways.« less
Sylman, Joanna L; Daalkhaijav, Uranbileg; Zhang, Ying; Gray, Elliot M; Farhang, Parsa A; Chu, Tiffany T; Zilberman-Rudenko, Jevgenia; Puy, Cristina; Tucker, Erik I; Smith, Stephanie A; Morrissey, James H; Walker, Travis W; Nan, Xiaolin L; Gruber, András; McCarty, Owen J T
2017-05-01
In the contact activation pathway of the coagulation, zymogen factor XII (FXII) is converted to FXIIa, which triggers activation of FXI leading to the activation of FIX and subsequent thrombin generation and fibrin formation. Feedback activation of FXI by thrombin has been shown to promote thrombin generation in a FXII-independent manner and FXIIa can bypass FXI to directly activate FX and prothrombin in the presence of highly negatively charged molecules, such as long-chain polyphosphates (LC polyP). We sought to determine whether activation of FXII or FXI differentially regulate the physical biology of fibrin formation. Fibrin formation was initiated with tissue factor, ellagic acid (EA), or LC polyP in the presence of inhibitors of FXI and FXII. Our data demonstrated that inhibition of FXI decreased the rate of fibrin formation and fiber network density, and increased the fibrin network strength and rate of fibrinolysis when gelation was initiated via the contact activation pathway with EA. FXII inhibition decreased the fibrin formation and fibrin density, and increased the fibrinolysis rate only when fibrin formation was initiated via the contact activation pathway with LC polyP. Overall, we demonstrate that inhibition of FXI and FXII distinctly alter the biophysical properties of fibrin.
Graff, L; Russell, J; Seashore, J; Tate, J; Elwell, A; Prete, M; Werdmann, M; Maag, R; Krivenko, C; Radford, M
2000-11-01
To test the hypothesis that physician errors (failure to diagnose appendicitis at initial evaluation) correlate with adverse outcome. The authors also postulated that physician errors would correlate with delays in surgery, delays in surgery would correlate with adverse outcomes, and physician errors would occur on patients with atypical presentations. This was a retrospective two-arm observational cohort study at 12 acute care hospitals: 1) consecutive patients who had an appendectomy for appendicitis and 2) consecutive emergency department abdominal pain patients. Outcome measures were adverse events (perforation, abscess) and physician diagnostic performance (false-positive decisions, false-negative decisions). The appendectomy arm of the study included 1, 026 patients with 110 (10.5%) false-positive decisions (range by hospital 4.7% to 19.5%). Of the 916 patients with appendicitis, 170 (18.6%) false-negative decisions were made (range by hospital 10.6% to 27.8%). Patients who had false-negative decisions had increased risks of perforation (r = 0.59, p = 0.058) and of abscess formation (r = 0.81, p = 0.002). For admitted patients, when the inhospital delay before surgery was >20 hours, the risk of perforation was increased [2.9 odds ratio (OR) 95% CI = 1.8 to 4.8]. The amount of delay from initial physician evaluation until surgery varied with physician diagnostic performance: 7.0 hours (95% CI = 6.7 to 7.4) if the initial physician made the diagnosis, 72.4 hours (95% CI = 51.2 to 93.7) if the initial office physician missed the diagnosis, and 63.1 hours (95% CI = 47.9 to 78.4) if the initial emergency physician missed the diagnosis. Patients whose diagnosis was initially missed by the physician had fewer signs and symptoms of appendicitis than patients whose diagnosis was made initially [appendicitis score 2.0 (95% CI = 1.6 to 2.3) vs 6.5 (95% CI = 6.4 to 6.7)]. Older patients (>41 years old) had more false-negative decisions and a higher risk of perforation or abscess (3.5 OR 95% CI = 2.4 to 5.1). False-positive decisions were made for patients who had signs and symptoms similar to those of appendicitis patients [appendicitis score 5.7 (95% CI = 5.2 to 6.1) vs 6.5 (95% CI = 6.4 to 6.7)]. Female patients had an increased risk of false-positive surgery (2.3 OR 95% CI = 1.5 to 3.4). The abdominal pain arm of the study included 1,118 consecutive patients submitted by eight hospitals, with 44 patients having appendicitis. Hospitals with observation units compared with hospitals without observation units had a higher "rule out appendicitis" evaluation rate [33.7% (95% CI = 27 to 38) vs 24.7% (95% CI = 23 to 27)] and a similar hospital admission rate (27.6% vs 24.7%, p = NS). There was a lower miss-diagnosis rate (15.1% vs 19.4%, p = NS power 0.02), lower perforation rate (19.0% vs 20.6%, p = NS power 0.05), and lower abscess rate (5.6% vs 6.9%, p = NS power 0.06), but these did not reach statistical significance. Errors in physician diagnostic decisions correlated with patient clinical findings, i.e., the missed diagnoses were on appendicitis patients with few clinical findings and unnecessary surgeries were on non-appendicitis patients with clinical findings similar to those of patients with appendicitis. Adverse events (perforation, abscess formation) correlated with physician false-negative decisions.
NAVAIR Portable Source Initiative (NPSI) Standard for Reusable Source Dataset Metadata (RSDM) V2.4
2012-09-26
defining a raster file format: <RasterFileFormat> <FormatName>TIFF</FormatName> <Order>BIP</Order> < DataType >8-BIT_UNSIGNED</ DataType ...interleaved by line (BIL); Band interleaved by pixel (BIP). element RasterFileFormatType/ DataType diagram type restriction of xsd:string facets
NASA Astrophysics Data System (ADS)
Kristensen, K.; Cui, T.; Zhang, H.; Gold, A.; Glasius, M.; Surratt, J. D.
2013-12-01
The formation of secondary organic aerosol (SOA) from both ozonolysis and hydroxyl radical (OH)-initiated oxidation of α-pinene under conditions of high nitric oxide (NO) concentrations with varying relative humidity (RH) and aerosol acidity was investigated in the University of North Carolina dual outdoor smog chamber facility. SOA formation from ozonolysis of α-pinene was enhanced relative to that from OH-initiated oxidation in the presence of initially high NO conditions. However, no effect of RH on SOA mass was evident. Ozone (O3)-initiated oxidation of α-pinene in the presence of ammonium sulfate (AS) seed coated with organic aerosol from OH-initiated oxidation of α-pinene showed reduced nucleation compared to ozonolysis in the presence of pure AS seed aerosol. The chemical composition of α-pinene SOA was investigated by ultra-performance liquid chromatography/electrospray ionization high-resolution quadrupole time-of-flight mass spectrometry (UPLC/ESI-HR-Q-TOFMS), with a focus on the formation of carboxylic acids and high-molecular weight dimer esters. A total of eight carboxylic acids and four dimer esters were identified, constituting between 8 and 12% of the total α-pinene SOA mass. OH-initiated oxidation of α-pinene in the presence of nitrogen oxides (NOx) resulted in the formation of highly oxidized carboxylic acids, such as 3-methyl-1,2,3-butanetricarboxylic acid (MBTCA) and diaterpenylic acid acetate (DTAA). The formation of dimer esters was observed only in SOA produced from the ozonolysis of α-pinene in the absence of NOx, with increased concentrations by a~factor of two at higher RH (50-90%) relative to lower RH (30-50%). The increased formation of dimer esters correlates with an observed increase in new particle formation at higher RH due to nucleation. Increased aerosol acidity was found to have a negligible effect on the formation of the dimer esters. SOA mass yield did not influence the chemical composition of SOA formed from α-pinene ozonolysis with respect to carboxylic acids and dimer esters. The results support the formation of the high-molecular weight dimer esters through gas-phase reactions of the stabilized Criegee Intermediate (sCI) formed from the ozonolysis of α-pinene. The high molecular weight and polar nature of dimer esters formed in the gas-phase may explain increased particle number concentration as a~result of homogenous nucleation. Since three of these dimer esters (i.e., pinyl-diaterpenyl ester (MW 358), pinyl-diaterebyl ester (MW 344) and pinonyl-pinyl ester (MW 368)) have been observed in both laboratory-generated and ambient fine organic aerosol samples, we conclude that the dimer esters observed in this study can be used as tracers for the O3-initiated oxidation of α-pinene, and are therefore indicative of enhanced anthropogenic activities, and that the high molecular weight and low volatility esters result in homogenous nucleation under laboratory conditions, increasing the particle number concentration.
NASA Astrophysics Data System (ADS)
Kristensen, K.; Cui, T.; Zhang, H.; Gold, A.; Glasius, M.; Surratt, J. D.
2014-04-01
The formation of secondary organic aerosol (SOA) from both ozonolysis and hydroxyl radical (OH)-initiated oxidation of α-pinene under conditions of high nitric oxide (NO) concentrations with varying relative humidity (RH) and aerosol acidity was investigated in the University of North Carolina dual outdoor smog chamber facility. SOA formation from ozonolysis of α-pinene was enhanced relative to that from OH-initiated oxidation in the presence of initially high-NO conditions. However, no effect of RH on SOA mass was evident. Ozone (O3)-initiated oxidation of α-pinene in the presence of ammonium sulfate (AS) seed coated with organic aerosol from OH-initiated oxidation of α-pinene showed reduced nucleation compared to ozonolysis in the presence of pure AS seed aerosol. The chemical composition of α-pinene SOA was investigated by ultra-performance liquid chromatography/electrospray ionization high-resolution quadrupole time-of-flight mass spectrometry (UPLC/ESI-HR-Q-TOFMS), with a focus on the formation of carboxylic acids and high-molecular weight dimers. A total of eight carboxylic acids and four dimers were identified, constituting between 8 and 12% of the total α-pinene SOA mass. OH-initiated oxidation of α-pinene in the presence of nitrogen oxides (NOx) resulted in the formation of highly oxidized carboxylic acids, such as 3-methyl-1,2,3-butanetricarboxylic acid (MBTCA) and diaterpenylic acid acetate (DTAA). The formation of dimers was observed only in SOA produced from the ozonolysis of α-pinene in the absence of NOx, with increased concentrations by a factor of two at higher RH (50-90%) relative to lower RH (30-50%). The increased formation of dimers correlates with an observed increase in new particle formation at higher RH due to nucleation. Increased aerosol acidity was found to have a negligible effect on the formation of the dimers. SOA mass yield did not influence the chemical composition of SOA formed from α-pinene ozonolysis with respect to carboxylic acids and dimers. The results support the formation of the high-molecular weight dimers through gas-phase reactions of the stabilized Criegee Intermediate (sCI) formed from the ozonolysis of α-pinene. The high molecular weight and polar nature of dimers formed in the gas phase may explain increased particle number concentration as a result of homogenous nucleation. Since three of these dimers (i.e. pinyl-diaterpenyl dimer (MW 358), pinyl-diaterebyl dimer (MW 344) and pinonyl-pinyl dimer (MW 368)) have been observed in both laboratory-generated and ambient fine organic aerosol samples, we conclude that the dimers observed in this study can be used as tracers for the O3-initiated oxidation of α-pinene, and are therefore indicative of enhanced anthropogenic activities, and that the high molecular weight and low volatility dimers result in homogenous nucleation under laboratory conditions, increasing the particle number concentration.
Star formation onset in baryonic disks: The role of a triaxial halo
NASA Astrophysics Data System (ADS)
Mazzei, P.; Curir, A.
2001-06-01
We investigate the effects of the onset of star formation on the growth of bar instability using a smooth particle hydrodynamics code implemented to account for chemo-photometric evolution from UV to near-IR wavelengths. We analyze the role of a non axisymmetric dark matter halo on the bar triggering and the feedback due to the ongoing star formation rate in the disk. We find that the dark matter halo plays a very important role in the evolution of the luminous matter. The star formation rate (SFR) depends indeed both on its mass, which leads the total gravitational field, and on its dynamical state. Stronger initial bursts of star formation are triggered in the more massive unrelaxed haloes than in the relaxed ones, which are also the more concentrated at the beginning. We point out further that the dark matter concentration is different in haloes with a different initial triaxiality ratio, suggesting a dependence of the SFR also on the halo geometry. By mapping the predicted B surface brightness of the new stars formed, we find that a luminous bar along the whole disk develops only in the first stages of such an instability, then later, new stars are born in the inner regions and the bar is reduced to the central 3-4 kpc. After 1.7 Gyr the young stellar component shows stronger bars in the presence of the relaxed haloes with a lower initial triaxiality ratio; strong bars still appear in the old star isodensity contours of the same systems, at variance with our results when star formation is switched off. The formation of new stars causes indeed a lower dynamical coupling between dark matter and baryonic particles, which lengthens the life-time of the bar. Colours and metallicity gradients of new stars allow us to understand deeply the observational consequences of initial geometry and dynamical state of the halo on the star formation process.
Surface characteristics and bioactivity of oxide film on titanium metal formed by thermal oxidation.
Park, Yeong-Joon; Song, Ho-Jun; Kim, In; Yang, Hong-So
2007-04-01
In this study, we characterized the surface of oxide film formed on titanium metal through the use of thermal treatment and investigated the effect of surface characteristics on the bioactivity of titanium. The as-received sample group was prepared by polishing and cleaning CP-Ti as a control group, and thermally oxidized sample groups were prepared by heat treating at 530, 600, 700, 800, 900, and 1000 degrees C respectively. Micro-morphology, crystalline structure, chemical composition, and binding state were evaluated using FE-SEM, XRD, and XPS. The bioactivity of sample groups was investigated by observing the degree of calcium phosphate formation from immersion testing in MEM. The surface characterization tests showed that hydroxyl group content in titanium oxide film was increased, as the density of titanium atoms was high and the surface area was large. In MEM immersion test, initial calcium phosphate formation was dependent upon the thickness of titanium oxide, and resultant calcium phosphate formation depended on the content of the hydroxyl group of the titanium oxide film surface.
NASA Technical Reports Server (NTRS)
Strahan, Susan E.; Douglass, Anne R.
2003-01-01
The Global Modeling Initiative has integrated two 35-year simulations of an ozone recovery scenario with an offline chemistry and transport model using two different meteorological inputs. Physically based diagnostics, derived from satellite and aircraft data sets, are described and then used to evaluate the realism of temperature and transport processes in the simulations. Processes evaluated include barrier formation in the subtropics and polar regions, and extratropical wave-driven transport. Some diagnostics are especially relevant to simulation of lower stratospheric ozone, but most are applicable to any stratospheric simulation. The temperature evaluation, which is relevant to gas phase chemical reactions, showed that both sets of meteorological fields have near climatological values at all latitudes and seasons at 30 hPa and below. Both simulations showed weakness in upper stratospheric wave driving. The simulation using input from a general circulation model (GMI(sub GCM)) showed a very good residual circulation in the tropics and northern hemisphere. The simulation with input from a data assimilation system (GMI(sub DAS)) performed better in the midlatitudes than at high latitudes. Neither simulation forms a realistic barrier at the vortex edge, leading to uncertainty in the fate of ozone-depleted vortex air. Overall, tracer transport in the offline GMI(sub GCM) has greater fidelity throughout the stratosphere than the GMI(sub DAS).
NASA Astrophysics Data System (ADS)
Clyde, W. C.; Khan, I. H.; Gingerich, P. D.
2003-12-01
Initial continental collision between India and Asia is thought to have caused significant changes to global climate and biota, yet its timing and biogeographic consequences are uncertain. Structural and geophysical evidence indicates initial collision during the early Paleogene, but sedimentary evidence of this has been controversial owing to the intense deformation and metamorphism along the suture zone. Modern orders of mammals that appeared abruptly on northern continents coincident with the global warming event marking the Paleocene-Eocene boundary are hypothesized to have originated on the Indian subcontinent, but no relevant paleontologic information has been available to test this idea. Here we present sedimentologic, paleomagnetic, and paleontologic results that show the lower Eocene Ghazij Formation of western Pakistan records continental sedimentation and mammalian dispersal associated with initial India-Asia collision. Sedimentologically, the Ghazij exhibits a clear transition from shallow-marine facies in the lower part, to paralic deltaic facies in the middle part, and continental fluvial facies in the upper part. Paleomagnetic data indicate that Ghazij deposition occurred just before a pronounced decrease in the sea-floor spreading rate of the Indian Ocean. Large fossil mammal assemblages show strong endemism in the middle part of the formation but increasing cosmopolitanism and affiliation with northern continents higher in the formation. Our results support the hypothesis that initial continent-continent contact occurred near the Paleocene-Eocene boundary along the northwest edge of the Indo-Pakistan plate and that subsequent closure occurred diachronously along the rest of the suture. However, it appears that during initial collision, modern orders of mammals dispersed into India rather than out of it.
Regulation of root hair initiation and expansin gene expression in Arabidopsis
NASA Technical Reports Server (NTRS)
Cho, Hyung-Taeg; Cosgrove, Daniel J.
2002-01-01
The expression of two Arabidopsis expansin genes (AtEXP7 and AtEXP18) is tightly linked to root hair initiation; thus, the regulation of these genes was studied to elucidate how developmental, hormonal, and environmental factors orchestrate root hair formation. Exogenous ethylene and auxin, as well as separation of the root from the medium, stimulated root hair formation and the expression of these expansin genes. The effects of exogenous auxin and root separation on root hair formation required the ethylene signaling pathway. By contrast, blocking the endogenous ethylene pathway, either by genetic mutations or by a chemical inhibitor, did not affect normal root hair formation and expansin gene expression. These results indicate that the normal developmental pathway for root hair formation (i.e., not induced by external stimuli) is independent of the ethylene pathway. Promoter analyses of the expansin genes show that the same promoter elements that determine cell specificity also determine inducibility by ethylene, auxin, and root separation. Our study suggests that two distinctive signaling pathways, one developmental and the other environmental/hormonal, converge to modulate the initiation of the root hair and the expression of its specific expansin gene set.
How to improve outcome in surgery for Proximal Hypospadias?
Qureshi, Abdul Hafeez; Zaidi, Syed Zafar
2016-02-01
To evaluate the role of subdartos fascial tissue as watertight layer in improving outcome for 2-stage proximal hypospadias surgery. The experimental study was conducted at the Department of Urology, Indus Hospital, Karachi, and comprised an audit of patients with proximal hypospadias who underwent surgery from July 1, 2007, to December 31, 2011. The initial two-stage repair of proximal hypospadias led to a high rate of urethrocutanous fistula formation (Group A), and, thus, a modification was introduced and subdartos facial double layer was applied over the urethral suture line (Group B). The results were compared regarding age, type of hypospadias, graft failure and urethrocutanous fistula in these patients. There were 27 patients in Group A and 16(59.3%) of them ended up having urethrocutanous fistula. Group B had 25 patients and only 2(8%) had fistula formation. The application of dartos facial flap waterproofing layer reduced fistula rate.
Determination of product branching ratio of the ClO self-reaction at 298 K
NASA Astrophysics Data System (ADS)
Horowitz, A.; Bauer, D.; Crowley, J. N.; Moortgat, G. K.
1993-07-01
The Cl2-sensitized continuous photolysis of O3 mixtures in O2 was investigated at 298 K using time resolved single wavelength and diode array spectroscopy to monitor the decay of O3 and the formation of OClO. Φ-O3 was found to be 4.1±0.4. This value, combined with the determination of the initial rates of OClO formation, allowed the evaluation of the following branching ratios into the three bimolecular disproportionation channels of ClO reactions; k3a/k3 = 0.40 ± 0.08, k3b/k3 = 0.42 ± 0.08 and k3c/k3 = 0.18 ± 0.02 where ClO + ClO → Cl2 + O2 (3a), ClO + ClO → Cl + Cl + O2 (3b) and ClO + ClO → Cl + OClO (3c).
NASA Astrophysics Data System (ADS)
Nazarova, D. P.; Portnyagin, M. V.; Krasheninnikov, S. P.; Mironov, N. L.; Sobolev, A. V.
2017-01-01
The formation conditions of the parental magmas of Gorely volcano, which is located behind a volcanic front in Southern Kamchatka, have been evaluated using the modern methods of micro-element thermobarometry. These magmas contained 1.7 ± 0.8 (2σ) wt % of H2O, the majority (82%) of which has been lost from inclusions. They crystallized at 1121 ± 17°C and an oxygen fugacity of ΔQFM 1.2 ± 0.2, and could have been produced by about 11% melting of an enriched MORB source (E-DMM) at a temperature of about 1270°C, and a pressure of about 1.5 GPa. A distinctive feature of Gorely volcano, compared with frontal volcanoes of Kamchatka, is the unusually high temperature (925 ± 20°C) of formation of the subduction component corresponding to the region of existence of water-bearing melts.
Unravelling the core microbiome of biofilms in cooling tower systems.
Di Gregorio, L; Tandoi, V; Congestri, R; Rossetti, S; Di Pippo, F
2017-11-01
In this study, next generation sequencing and catalyzed reporter deposition fluorescence in situ hybridization, combined with confocal microscopy, were used to provide insights into the biodiversity and structure of biofilms collected from four full-scale European cooling systems. Water samples were also analyzed to evaluate the impact of suspended microbes on biofilm formation. A common core microbiome, containing members of the families Sphingomonadaceae, Comamonadaceae and Hyphomicrobiaceae, was found in all four biofilms, despite the water of each coming from different sources (river and groundwater). This suggests that selection of the pioneer community was influenced by abiotic factors (temperature, pH) and tolerances to biocides. Members of the Sphingomonadaceae were assumed to play a key role in initial biofilm formation. Subsequent biofilm development was driven primarily by light availability, since biofilms were dominated by phototrophs in the two studied 'open' systems. Their interactions with other microbial populations then shaped the structure of the mature biofilm communities analyzed.
Jézéquel, Ronan; Receveur, Justine; Nedwed, Tim; Le Floch, Stéphane
2018-02-01
A test program was conducted at laboratory and pilot scale to assess the ability of clays used in drilling mud (calcite, bentonite and barite) to create oil-mineral aggregates and disperse crude oil under arctic conditions. Laboratory tests were performed in order to determine the most efficient conditions (type of clay, MOR (Mineral/Oil Ratio), mixing energy) for OMA (Oil Mineral Aggregate) formation. The dispersion rates of four crude oils were assessed at two salinities. Dispersion was characterized in terms of oil concentration in the water column and median OMA size. Calcite appeared to be the best candidate at a MOR of 2:5. High mixing energy was required to initiate OMA formation and low energy was then necessary to prevent the OMAs from resurfacing. Oil dispersion using Corexit 9500 was compared with oil dispersion using mineral fines. Copyright © 2017 Elsevier Ltd. All rights reserved.
An integrated approach to model strain localization bands in magnesium alloys
NASA Astrophysics Data System (ADS)
Baxevanakis, K. P.; Mo, C.; Cabal, M.; Kontsos, A.
2018-02-01
Strain localization bands (SLBs) that appear at early stages of deformation of magnesium alloys have been recently associated with heterogeneous activation of deformation twinning. Experimental evidence has demonstrated that such "Lüders-type" band formations dominate the overall mechanical behavior of these alloys resulting in sigmoidal type stress-strain curves with a distinct plateau followed by pronounced anisotropic hardening. To evaluate the role of SLB formation on the local and global mechanical behavior of magnesium alloys, an integrated experimental/computational approach is presented. The computational part is developed based on custom subroutines implemented in a finite element method that combine a plasticity model with a stiffness degradation approach. Specific inputs from the characterization and testing measurements to the computational approach are discussed while the numerical results are validated against such available experimental information, confirming the existence of load drops and the intensification of strain accumulation at the time of SLB initiation.
Two-dimensional and three-dimensional evaluation of the deformation relief
NASA Astrophysics Data System (ADS)
Alfyorova, E. A.; Lychagin, D. V.
2017-12-01
This work presents the experimental results concerning the research of the morphology of the face-centered cubic single crystal surface after compression deformation. Our aim is to identify the method of forming a quasiperiodic profile of single crystals with different crystal geometrical orientation and quantitative description of deformation structures. A set of modern methods such as optical and confocal microscopy is applied to determine the morphology of surface parameters. The results show that octahedral slip is an integral part of the formation of the quasiperiodic profile surface starting with initial strain. The similarity of the formation process of the surface profile at different scale levels is given. The size of consistent deformation regions is found. This is 45 µm for slip lines ([001]-single crystal) and 30 µm for mesobands ([110]-single crystal). The possibility of using two- and three-dimensional roughness parameters to describe the deformation structures was shown.
Resistive MHD Simulation of Quasi-Single-Helicity State on KTX
NASA Astrophysics Data System (ADS)
Luo, Bing; Zhu, Ping; Li, Hong; Liu, Wandong
2016-10-01
The potential formation of quasi-single-helicity (QSH) state on Keda Torus eXperiment (KTX) is evaluated in resistive MHD simulations using the NIMROD code. In this work, we focus on the effects of finite resistivity on the mode structure and characteristics of the dominant linear and nonlinear resistive tearing-mode instability in a finite β, cylindrical reversed field pinch model configuration for KTX. In the typical resistivity regimes of KTX where Lundquist number S =105 , the plasma reaches a steady QSH state after the initial transient phase of multiple helicities. The dominat mode of the QSH state is developed from the dominat linear tearing mode instability. The conditions for and the variations of the formation of QSH states in different resistivity regimes of KTX will be reported and discussed. Supported by National Magnetic Confinement Fusion Science Program of China Grant Nos. 2014GB124002, 2015GB101004, 2011GB106000, and 2011GB106003.
DOE Office of Scientific and Technical Information (OSTI.GOV)
NONE
SCALE--a modular code system for Standardized Computer Analyses Licensing Evaluation--has been developed by Oak Ridge National Laboratory at the request of the US Nuclear Regulatory Commission. The SCALE system utilizes well-established computer codes and methods within standard analysis sequences that (1) allow an input format designed for the occasional user and/or novice, (2) automated the data processing and coupling between modules, and (3) provide accurate and reliable results. System development has been directed at problem-dependent cross-section processing and analysis of criticality safety, shielding, heat transfer, and depletion/decay problems. Since the initial release of SCALE in 1980, the code system hasmore » been heavily used for evaluation of nuclear fuel facility and package designs. This revision documents Version 4.3 of the system.« less
Intraspecific variation in nutrient reserve use during clutch formation by Lesser Scaup
Esler, Daniel N.; Grand, James B.; Afton, Alan D.
2001-01-01
We studied nutrient reserve dynamics of female Lesser Scaup (Aythya affinis) to identify sources of intraspecific variation in strategies of nutrient acquisition for meeting the high nutritional and energetic costs of egg formation. We collected data from interior Alaska and combined these with data for Lesser Scaup from midcontinent breeding areas (Afton and Ankney 1991), allowing a rangewide analysis for the species. We found little evidence that nutrient reserve use differed between Alaskan and midcontinent Lesser Scaup, except that subarctic birds used a small amount of protein reserves when forming eggs, whereas midcontinent birds did not. Mineral reserves contributed relatively little to the clutch, but endogenous lipid accounted for approximately two-thirds of the lipid in the clutch. Levels of endogenous lipid and protein at initiation of clutch formation declined with date of initiation. Also, absolute amounts of lipid and protein reserves used declined through the season, corresponding to smaller clutch sizes. Our data are consistent with a seasonally variable threshold of lipid reserves for initiation of clutch formation and considerable reliance on lipid reserves, suggestive of lipid control of productivity via effects on clutch size and initiation dates. However, our data cannot refute the hypothesis that clutch size or initiation dates are set by other factors that in turn dictate the amount of lipid reserves that are stored and used. Despite uncertainty regarding the role of nutrient limitations on productivity, maintenance of adequate food resources on winter, migration, and breeding areas should be a management concern, given the high costs of clutch formation by Lesser Scaup, evidence of recent population declines, and potential links between nutrition and productivity.
General Relativistic MHD Simulations of Jet Formation
NASA Technical Reports Server (NTRS)
Mizuno, Y.; Nishikawa, K.-I.; Hardee, P.; Koide, S.; Fishman, G. J.
2005-01-01
We have performed 3-dimensional general relativistic magnetohydrodynamic (GRMHD) simulations of jet formation from an accretion disk with/without initial perturbation around a rotating black hole. We input a sinusoidal perturbation (m = 5 mode) in the rotation velocity of the accretion disk. The simulation results show the formation of a relativistic jet from the accretion disk. Although the initial perturbation becomes weakened by the coupling among different modes, it survives and triggers lower modes. As a result, complex non-axisymmetric density structure develops in the disk and the jet. Newtonian MHD simulations of jet formation with a non-axisymmetric mode show the growth of the m = 2 mode but GRMHD simulations cannot see the clear growth of the m = 2 mode.
Flores-Olvera, Hilda; Vrijdaghs, Alexander; Ochoterena, Helga; Smets, Erik
2011-01-01
Background and Aims Within Chenopodioideae, Atripliceae have been distinguished by two bracteoles enveloping the female flowers/fruits, whereas in other tribes flowers are described as ebracteolate with persistent perianth. Molecular phylogenetic hypotheses suggest ‘bracteoles’ to be homoplastic. The origin of the bracteoles was explained by successive inflorescence reductions. Flower reduction was used to explain sex determination. Therefore, floral ontogeny was studied to evaluate the nature of the bracteoles and sex determination in Atripliceae. Methods Inflorescences of species of Atriplex, Chenopodium, Dysphania and Spinacia oleracea were investigated using light microscopy and scanning electron microscopy. Key Results The main axis of the inflorescence is indeterminate with elementary dichasia as lateral units. Flowers develop centripetally, with first the formation of a perianth primordium either from a ring primordium or from five individual tepal primordia fusing post-genitally. Subsequently, five stamen primordia originate, followed by the formation of an annular ovary primordium surrounding a central single ovule. Flowers are either initially hermaphroditic remaining bisexual and/or becoming functionally unisexual at later stages, or initially unisexual. In the studied species of Atriplex, female flowers are strictly female, except in A. hortensis. In Spinacia, female and male flowers are unisexual at all developmental stages. Female flowers of Atriplex and Spinacia are protected by two accrescent fused tepal lobes, whereas the other perianth members are absent. Conclusions In Atriplex and Spinacia modified structures around female flowers are not bracteoles, but two opposite accrescent tepal lobes, parts of a perianth persistent on the fruit. Flowers can achieve sexuality through many different combinations; they are initially hermaphroditic, subsequently developing into bisexual or functionally unisexual flowers, with the exception of Spinacia and strictly female flowers in Atriplex, which are unisexual from the earliest developmental stages. There may be a relationship between the formation of an annular perianth primordium and flexibility in floral sex determination. PMID:21852278
Review of nutrition labeling formats.
Geiger, C J; Wyse, B W; Parent, C R; Hansen, R G
1991-07-01
This article examines nutrition labeling history as well as the findings of nine research studies of nutrition labeling formats. Nutrition labeling regulations were announced in 1973 and have been periodically amended since then. In response to requests from consumers and health care professionals for revision of the labeling system, the Food and Drug Administration initiated a three-phase plan for reform of nutrition labeling in 1990. President Bush signed the Nutrition Labeling and Education Act in November 1990. Literature analysis revealed that only nine studies with an experimental design have focused on nutrition labeling since 1971. Four were conducted before 1975, which was the year that nutrition labeling was officially implemented, two were conducted in 1980, and three were conducted after 1986. Only two of the nine studies supported the traditional label format mandated by the Code of Federal Regulations, and one study partially supported it. Four of the nine studies that evaluated graphic presentations of nutrition information found that consumer comprehension of nutrition information was improved with a graphic format for nutrition labeling: three studies supported the use of bar graphs and one study supported the use of a pie chart. Full disclosure (ie, complete nutrient and ingredient labeling) was preferred by consumers in two of the three studies that examined this variable. The third study supported three types of information disclosure dependent upon socioeconomic class. In those studies that tested graphics, a bar graph format was significantly preferred and showed better consumer comprehension than the traditional format.
The taccalonolides and paclitaxel cause distinct effects on microtubule dynamics and aster formation
2014-01-01
Background Microtubule stabilizers suppress microtubule dynamics and, at the lowest antiproliferative concentrations, disrupt the function of mitotic spindles, leading to mitotic arrest and apoptosis. At slightly higher concentrations, these agents cause the formation of multiple mitotic asters with distinct morphologies elicited by different microtubule stabilizers. Results We tested the hypothesis that two classes of microtubule stabilizing drugs, the taxanes and the taccalonolides, cause the formation of distinct aster structures due, in part, to differential effects on microtubule dynamics. Paclitaxel and the taccalonolides suppressed the dynamics of microtubules formed from purified tubulin as well as in live cells. Both agents suppressed microtubule dynamic instability, with the taccalonolides having a more pronounced inhibition of microtubule catastrophe, suggesting that they stabilize the plus ends of microtubules more effectively than paclitaxel. Live cell microscopy was also used to evaluate the formation and resolution of asters after drug treatment. While each drug had similar effects on initial formation, substantial differences were observed in aster resolution. Paclitaxel-induced asters often coalesced over time resulting in fewer, larger asters whereas numerous compact asters persisted once they were formed in the presence of the taccalonolides. Conclusions We conclude that the increased resistance of microtubule plus ends to catastrophe may play a role in the observed inability of taccalonolide-induced asters to coalesce during mitosis, giving rise to the distinct morphologies observed after exposure to these agents. PMID:24576146
Solid-state synthesis of YAG powders through microwave coupling of oxide/carbon particulate mixtures
Wildfire, Christina; Sabolsky, Edward M.; Spencer, Michael J.; ...
2017-06-14
The rapid synthesis of yttrium aluminum garnet (Y 3Al 15O 12, YAG) powder was investigated through the use of microwave irradiation of the oxide precursor system. For this investigation, an external hybrid heating source was not used. Instead, the rapid heating of the precursor materials (yttria and alumina powders, which are typically transparent to 2.45 GHz microwaves) was initiated by mixing an intrinsic absorbing material (carbon) into the original oxide precursors. The effect of the carbon characteristics, such as carbon source, concentration, particle size, and agglomerate microstructure were evaluated on the efficiency of coupling and resultant oxide reaction. The microwavemore » power was varied to optimize the YAG conversion and eliminate intermediate phase formation. Interactions between the conductive carbon particles and the dielectric oxides within the microwave exposure produced local arching and micro-plasma formation within the powder bed, resulting in the rapid formation of the refractory YAG composition. This optimal conduction led to temperatures of 1000°C that could be achieved in less than 5 min resulting in the formation of > 90 vol% YAG. The understanding of a conductor/dielectric particulate system here, provided insight into possible application of similar systems where microwave irradiation could be used for enhanced solid-state formation, local melting events, and gas phase reactions with a composite powder media.« less
Biogenic amines in fish: roles in intoxication, spoilage, and nitrosamine formation--a review.
Al Bulushi, Ismail; Poole, Susan; Deeth, Hilton C; Dykes, Gary A
2009-04-01
Biogenic amines are non-volatile amines formed by decarboxylation of amino acids. Although many biogenic amines have been found in fish, only histamine, cadaverine, and putrescine have been found to be significant in fish safety and quality determination. Despite a widely reported association between histamine and scombroid food poisoning, histamine alone appears to be insufficient to cause food toxicity. Putrescine and cadaverine have been suggested to potentiate histamine toxicity. With respect to spoilage on the other hand, only cadaverine has been found to be a useful index of the initial stage of fish decomposition. The relationship between biogenic amines, sensory evaluation, and trimethylamine during spoilage are influenced by bacterial composition and free amino acid content. A mesophilic bacterial count of log 6-7 cfu/g has been found to be associated with 5 mg histamine/100 g fish, the Food and Drug Administration (FDA) maximum allowable histamine level. In vitro studies have shown the involvement of cadaverine and putrescine in the formation of nitrosamines, nitrosopiperidine (NPIP), and nitrosopyrrolidine (NPYR), respectively. In addition, impure salt, high temperature, and low pH enhance nitrosamine formation, whereas pure sodium chloride inhibits their formation. Understanding the relationships between biogenic amines and their involvement in the formation of nitrosamines could explain the mechanism of scombroid poisoning and assure the safety of many fish products.
Ho, Hanley J; Chan, Yin Ying; Ibrahim, Muhamad Alif Bin; Wagle, Anurupa A; Wong, Christina M; Chow, Angela
2017-11-07
Adult influenza and pneumococcal vaccination rates in Singapore are low, and factors influencing knowledge and attitudes of seniors towards influenza, pneumonia and their respective vaccines are not well-known. Our study aims to understand the barriers and facilitators towards getting influenza and pneumococcal vaccinations among seniors in Singapore, and subsequently inform the conduct of a relevant community-based educational intervention, as well as evaluate the intervention outcomes. We performed a mixed methods study with two components: Firstly, formative research was conducted among community-dwelling seniors, using focus group discussions (FGDs), to understand their knowledge and attitudes towards influenza, pneumonia and their respective vaccines. Next, a quantitative study was conducted to evaluate knowledge of seniors and the effectiveness of an educational intervention. Four FGDs were organised with 32 participants, who were predominantly female, of lower educational background, and residing in government rental flats. Participants had varying levels of knowledge and many misconceptions about influenza, pneumonia and their respective vaccinations, with concerns about side effects and vaccine effectiveness. The formative research results were used to inform a community-based educational intervention for seniors. Our subsequent evaluation included 604 elderly participants, mainly from lower educational and socio-economic strata, who initially demonstrated poor knowledge scores (median score 5 out of 9, IQR 4-5). Following our intervention, median knowledge score improved to 7 (IQR 6-8) (p < .0001). Significant improvements in knowledge scores were observed across genders, age strata, education levels, and housing types. Our formative research identified knowledge gaps among community-dwelling seniors which affected their attitudes towards vaccination uptake. Key findings were taken into consideration when implementing the educational intervention. Our community-based intervention was effective in improving knowledge and attitudes, and could be used as a cue to action for short-term behaviour changes. Copyright © 2017 Elsevier Ltd. All rights reserved.
Toxicity evaluation of surface water treated with different disinfectants in HepG2 cells.
Marabini, Laura; Frigerio, Silvia; Chiesara, Enzo; Radice, Sonia
2006-01-01
It is well known that water disinfection through chlorination causes the formation of a mixture of disinfection by-products (DBPs), many of which are genotoxic and carcinogenic. To demonstrate the formation of such compounds, a pilot water plant supplied with water from Lake Trasimeno was set up at the waterworks of Castiglione del Lago (PG, Italy). The disinfectants, continuously added to pre-filtered lake water flowing into three different basins, were sodium hypochlorite, chlorine dioxide and peracetic acid, an alternative disinfectant used until now for disinfecting waste waters, but not yet studied for a possible use in drinking water treatment. The aim of this study was to evaluate the formation during the disinfection processes of some toxic compounds that could explain the genotoxic effects of drinking waters. Differently treated waters were concentrated by solid-phase adsorption on silica C(18) columns and toxicity was assessed in a line of human hepatoma cells (HepG2), a metabolically competent cellular line very useful for human risk evaluation. The seasonal variability of the physical-chemical water characteristics (AOX, UV 254 nm, potential formation of THM, pH and temperature) made indispensable experimentation with water samples taken during the various seasons. Autumn waters cause greater toxicity compared to those of other seasons, in particular dilution of the concentrate at 0.5l equivalent of disinfected waters with chlorine dioxide and peracetic acid causes a 55% reduction in cellular vitality while the cellular vitality is over 80% with the all other water concentrates. Moreover it is very interesting underline that non-cytotoxic quantities of the autumnal water concentrates cause, after 2h treatment, a decrease in GSH and a statistically significant increase in oxygen radicals, while after prolonged treatment (24h) cause a GSH increase, without variations in the oxygen radical content. This phenomenon could be interpreted as the cellular adaptation response to an initial oxidative stress.
Usability evaluation of intradermal adapters (IDA).
Tsals, Izrail
2017-03-27
Intradermal adapter device technology minimizes the complexity of the Mantoux technique, thereby providing predictable, reproducible intradermal (ID) injections and removing the concerns regarding the ease and reliability of Mantoux technique when using conventional needle and syringe. The technology employs a simple device with geometry designed to gently deform the skin surface and the subcutaneous tissue, providing the ideal angle and depth of needle insertion for consistently successful intradermal injections. The results of this development were presented at the First, Second and Third Skin Vaccination Summits in 2011, 2013 and 2015 respectively [1,2,3]. The current publication addresses the performance of intradermal adapters (IDA) evaluated in three preclinical studies. The evaluations were based on the assessment of bleb formation in a skin model, an accepted indicator of ID injection success. All evaluated devices share the same proprietary dermal interface technology. Devices instituting this design are easy to use, require minimal training, and employ conventionally molded parts and cannula. These studies evaluated IDAs of initial design integral with luer lock needles, IDAs for use with conventional syringes, and intradermal adapters for use with auto disable syringes (ADID adapters). The evaluated ID adapters were intended to consistently place the lancet of the needle at a depth of 0.75mm from the skin's surface. This placement depth addresses the variation in the skin thickness at immunization sites for the majority of patients independent of many other variables. Most participants preferred the intradermal adapter method over the traditional Mantoux and identified a need for the adapter at their workplace. Evaluation of IDAs by registered nurses indicated these devices increase success of bleb formation. The use of IDA increased the success of forming blebs by about 30%. Nurses felt the injections were much easier to perform, in particular by novices. Copyright © 2016 Elsevier Ltd. All rights reserved.
[Pharmacogenic osteoporosis beyond cortisone. Proton pump inhibitors, glitazones and diuretics].
Kann, P H; Hadji, P; Bergmann, R S
2014-05-01
[corrected] There are many drugs which can cause osteoporosis or at least favor its initiation. The effect of hormones and drugs with antihormonal activity, such as glucocorticoids and aromatase inhibitors, on initiation of osteoporosis is well known. In addition, proton pump inhibitors, glitazones and diuretics also influence the formation of osteoporosis. The results of currently available studies on the correlation between proton pump inhibitors, glitazones and diuretics on formation of osteoporosis were evaluated and summarized. Proton pump inhibitors and glitazones increase the risk for osteoporotic fractures. Loop diuretics may slightly increase fracture risk, whereas thiazides were shown to be osteoprotective by reducing fracture probability on a relevant scale. Proton pump inhibitors should not be prescribed without serious consideration and then only as long as necessary. Alternatively, the administration of the less effective H2 antagonists should be considered when possible due to the reduction of acid secretion. Because the long-term intake of thiazides is associated with a clinically relevant reduction in the risk of fractures and they are economic and well-tolerated, prescription can be thoroughly recommended within the framework of differential diagnostic considerations in an appropriate clinical context. The briefly increased risk of falling immediately after starting diuretic therapy is the only point which needs to be considered.
Towards the damage evaluation using Gurson-Tvergaard-Needleman (GTN) model for hot forming processes
NASA Astrophysics Data System (ADS)
Imran, Muhammad; Bambach, Markus
2018-05-01
In the production of semi-finished metal products, hot forming is used to eliminate the pores and voids from the casting process under compressive stresses and to modify the microstructure for further processing. In the case of caliber and flat rolling processes, tensile stresses occur at certain roll gap ratios which promote pore formation on nonmetallic inclusion. The formation of new pores contributes to ductile damage and reduces the load carrying capacity of the material. In the literature, the damage nucleation and growth during the hot forming process are not comprehensively described. The aim of this study is to understand the damage initiation and growth mechanism during hot forming processes. Hot tensile tests are performed at different temperatures and strain rates for 16MnCrS5 steel. To investigate the influence of geometrical variations on the damage mechanism, specimens with different stress triaxiality ratios are used. Finite element simulations using the Gurson-Tvergaard-Needleman (GTN) damage model are performed to estimate the critical void fraction for the damage initiation and the evolution of the void volume fraction. The results showed that the GTN model underestimates the softening of the material due to the independence of the temperature and the strain rate.
Bernhardt, C.E.; Willard, D.A.
2009-01-01
The ridge and slough landscape of the Florida Everglades consists of a mosaic of linear sawgrass ridges separated by deeper-water sloughs with tree islands interspersed throughout the landscape. We used pollen assemblages from transects of sediment cores spanning sawgrass ridges, sloughs, and ridge-slough transition zones to determine the timing of ridge and slough formation and to evaluate the response of components of the ridge and slough landscape to climate variability and 20th-century water management. These pollen data indicate that sawgrass ridges and sloughs have been vegetationally distinct from one another since initiation of the Everglades wetland in mid-Holocene time. Although the position and community composition of sloughs have remained relatively stable throughout their history, modern sawgrass ridges formed on sites that originally were occupied by marshes. Ridge formation and maturation were initiated during intervals of drier climate (the Medieval Warm Period and the Little Ice Age) when the mean position of the Intertropical Convergence Zone shifted southward. During these drier intervals, marsh taxa were more common in sloughs, but they quickly receded when precipitation increased. Comparison with regional climate records suggests that slough vegetation is strongly influenced by North Atlantic Oscillation variability, even under 20th-century water management practices. ?? 2009 by the Ecological Society of America.
Mobile healthcare information management utilizing Cloud Computing and Android OS.
Doukas, Charalampos; Pliakas, Thomas; Maglogiannis, Ilias
2010-01-01
Cloud Computing provides functionality for managing information data in a distributed, ubiquitous and pervasive manner supporting several platforms, systems and applications. This work presents the implementation of a mobile system that enables electronic healthcare data storage, update and retrieval using Cloud Computing. The mobile application is developed using Google's Android operating system and provides management of patient health records and medical images (supporting DICOM format and JPEG2000 coding). The developed system has been evaluated using the Amazon's S3 cloud service. This article summarizes the implementation details and presents initial results of the system in practice.
Lessing, P.; Messina, C.P.; Fonner, R.F.
1983-01-01
Landslide risk can be assessed by evaluating geological conditions associated with past events. A sample of 2,4 16 slides from urban areas in West Virginia, each with 12 associated geological factors, has been analyzed using SAS computer methods. In addition, selected data have been normalized to account for areal distribution of rock formations, soil series, and slope percents. Final calculations yield landslide risk assessments of 1.50=high risk. The simplicity of the method provides for a rapid, initial assessment prior to financial investment. However, it does not replace on-site investigations, nor excuse poor construction. ?? 1983 Springer-Verlag New York Inc.
Studies toward brevisulcenal F via convergent strategies for marine ladder polyether synthesis.
Katcher, Matthew; Jamison, Timothy F
2018-03-15
Shortly after the initial isolation of marine ladder polyether natural products, biomimetic epoxide-opening cascade reactions were proposed as an efficient strategy for the synthesis of these compounds. However, difficulties in assembling the cascade precursors have limited the realization of these cascades. In this report, we describe strategies that provide convergent access to cascade precursors via regioselective allylation and efficient fragment coupling. We then investigate epoxide-opening cascades promoted by strong bases for the formation of fused tetrahydropyrans. These strategies are evaluated in the context of the synthesis of rings CDEFG of brevisulcenal F.
In situ Probe Science at Saturn
NASA Technical Reports Server (NTRS)
Atkinson, D.H.; Lunine, J.I.; Simon-Miller, A. A.; Atreya, S. K.; Brinckerhoff, W.; Colaprete, A.; Coustenis, A.; Fletcher, L. N.; Guillot, T.; Lebreton, J.-P.;
2014-01-01
A fundamental goal of solar system exploration is to understand the origin of the solar system, the initial stages, conditions, and processes by which the solar system formed, how the formation process was initiated, and the nature of the interstellar seed material from which the solar system was born. Key to understanding solar system formation and subsequent dynamical and chemical evolution is the origin and evolution of the giant planets and their atmospheres.
Reaction mechanisms in cellulose pyrolysis: a literature review
DOE Office of Scientific and Technical Information (OSTI.GOV)
Molton, P.M.; Demmitt, T.F.
1977-08-01
A bibliographic review of 195 references is presented outlining the history of the research into the mechanisms of cellulose pyrolysis. Topics discussed are: initial product identification, mechanism of initial formation of levoglucosan, from cellulose and from related compounds, decomposition of cellulose to other compounds, formation of aromatics, pyrolysis of levoglucosan, crosslinking of cellulose, pyrolytic reactions of cellulose derivatives, and the effects of inorganic salts on the pyrolysis mechanism. (JSR)
Cross-validated detection of crack initiation in aerospace materials
NASA Astrophysics Data System (ADS)
Vanniamparambil, Prashanth A.; Cuadra, Jefferson; Guclu, Utku; Bartoli, Ivan; Kontsos, Antonios
2014-03-01
A cross-validated nondestructive evaluation approach was employed to in situ detect the onset of damage in an Aluminum alloy compact tension specimen. The approach consisted of the coordinated use primarily the acoustic emission, combined with the infrared thermography and digital image correlation methods. Both tensile loads were applied and the specimen was continuously monitored using the nondestructive approach. Crack initiation was witnessed visually and was confirmed by the characteristic load drop accompanying the ductile fracture process. The full field deformation map provided by the nondestructive approach validated the formation of a pronounced plasticity zone near the crack tip. At the time of crack initiation, a burst in the temperature field ahead of the crack tip as well as a sudden increase of the acoustic recordings were observed. Although such experiments have been attempted and reported before in the literature, the presented approach provides for the first time a cross-validated nondestructive dataset that can be used for quantitative analyses of the crack initiation information content. It further allows future development of automated procedures for real-time identification of damage precursors including the rarely explored crack incubation stage in fatigue conditions.
Haudek, Kevin C.; Kaplan, Jennifer J.; Knight, Jennifer; Long, Tammy; Merrill, John; Munn, Alan; Nehm, Ross; Smith, Michelle; Urban-Lurain, Mark
2011-01-01
Concept inventories, consisting of multiple-choice questions designed around common student misconceptions, are designed to reveal student thinking. However, students often have complex, heterogeneous ideas about scientific concepts. Constructed-response assessments, in which students must create their own answer, may better reveal students’ thinking, but are time- and resource-intensive to evaluate. This report describes the initial meeting of a National Science Foundation–funded cross-institutional collaboration of interdisciplinary science, technology, engineering, and mathematics (STEM) education researchers interested in exploring the use of automated text analysis to evaluate constructed-response assessments. Participants at the meeting shared existing work on lexical analysis and concept inventories, participated in technology demonstrations and workshops, and discussed research goals. We are seeking interested collaborators to join our research community. PMID:21633063
Haudek, Kevin C; Kaplan, Jennifer J; Knight, Jennifer; Long, Tammy; Merrill, John; Munn, Alan; Nehm, Ross; Smith, Michelle; Urban-Lurain, Mark
2011-01-01
Concept inventories, consisting of multiple-choice questions designed around common student misconceptions, are designed to reveal student thinking. However, students often have complex, heterogeneous ideas about scientific concepts. Constructed-response assessments, in which students must create their own answer, may better reveal students' thinking, but are time- and resource-intensive to evaluate. This report describes the initial meeting of a National Science Foundation-funded cross-institutional collaboration of interdisciplinary science, technology, engineering, and mathematics (STEM) education researchers interested in exploring the use of automated text analysis to evaluate constructed-response assessments. Participants at the meeting shared existing work on lexical analysis and concept inventories, participated in technology demonstrations and workshops, and discussed research goals. We are seeking interested collaborators to join our research community.
Distortion of Magnetic Fields in a Starless Core II: 3D Magnetic Field Structure of FeSt 1-457
NASA Astrophysics Data System (ADS)
Kandori, Ryo; Tamura, Motohide; Tomisaka, Kohji; Nakajima, Yasushi; Kusakabe, Nobuhiko; Kwon, Jungmi; Nagayama, Takahiro; Nagata, Tetsuya; Tatematsu, Ken'ichi
2017-10-01
Three-dimensional (3D) magnetic field information on molecular clouds and cores is important for revealing their kinematical stability (magnetic support) against gravity, which is fundamental for studying the initial conditions of star formation. In the present study, the 3D magnetic field structure of the dense starless core FeSt 1-457 is determined based on the near-infrared polarimetric observations of the dichroic polarization of background stars and simple 3D modeling. With an obtained angle of line-of-sight magnetic inclination axis {θ }{inc} of 45^\\circ +/- 10^\\circ and previously determined plane-of-sky magnetic field strength {B}{pol} of 23.8 ± 12.1 μ {{G}}, the total magnetic field strength for FeSt 1-457 is derived to be 33.7 ± 18.0 μ {{G}}. The critical mass of FeSt 1-457, evaluated using both magnetic and thermal/turbulent support is {M}{cr}=3.70+/- 0.92 {M}⊙ , which is identical to the observed core mass, {M}{core}=3.55+/- 0.75 {M}⊙ . We thus conclude that the stability of FeSt 1-457 is in a condition close to the critical state. Without infalling gas motion and no associated young stars, the core is regarded to be in the earliest stage of star formation, I.e., the stage just before the onset of dynamical collapse following the attainment of a supercritical condition. These properties could make FeSt 1-457 one of the best starless cores for future studies of the initial conditions of star formation.
Köhler, G; Hofmann, A; Lechner, M; Mayer, F; Wundsam, H; Emmanuel, K; Fortelny, R H
2016-02-01
In patients with terminal ostomies, parastomal hernias (PSHs) occur on a frequent basis. They are commonly associated with various degrees of complaints and occasionally lead to life-threatening complications. Various strategies and measures have been tested and evaluated, but to date there is a lack of published evidence with regard to the best surgical technique for the prevention of PSH development. We conducted a retrospective analysis of prospectively collected data of eighty patients, who underwent elective permanent ostomy formation between 2009 and 2014 by means of prophylactic implantation of a three-dimensional (3D) funnel mesh in intraperitoneal onlay (IPOM) position. PSH developed in three patients (3.75%). No mesh-related complications were encountered and none of the implants had to be removed. Ostomy-related complications had to be noted in seven (8.75%) cases. No manifestation of ostomy prolapse occurred. Follow-up time was a median 21 (range 3-47) months. The prophylactical implantation of a specially shaped, 3D mesh implant in IPOM technique during initial formation of a terminal enterostomy is safe, highly efficient and comparatively easy to perform. As opposed to what can be achieved with flat or keyhole meshes, the inner boundary areas of the ostomy itself can be well covered and protected from the surging viscera with the 3D implants. At the same time, the vertical, tunnel-shaped part of the mesh provides sufficient protection from an ostomy prolapse. Further studies will be needed to compare the efficacy of various known approaches to PSH prevention.
Cheng, Bi-Hua; Chu, Tien-Min G.; Chang, Chawnshang; Kang, Hong-Yo; Huang, Ko-En
2013-01-01
Loss of large bone segments due to fracture resulting from trauma or tumor removal is a common clinical problem. The goal of this study was to evaluate the use of scaffolds containing testosterone, bone morphogenetic protein-2 (BMP-2), or a combination of both for treatment of critical-size segmental bone defects in mice. A 2.5-mm wide osteotomy was created on the left femur of wildtype and androgen receptor knockout (ARKO) mice. Testosterone, BMP-2, or both were delivered locally using a scaffold that bridged the fracture. Results of X-ray imaging showed that in both wildtype and ARKO mice, BMP-2 treatment induced callus formation within 14 days after initiation of the treatment. Testosterone treatment also induced callus formation within 14 days in wildtype but not in ARKO mice. Micro-computed tomography and histological examinations revealed that testosterone treatment caused similar degrees of callus formation as BMP-2 treatment in wildtype mice, but had no such effect in ARKO mice, suggesting that the androgen receptor is required for testosterone to initiate fracture healing. These results demonstrate that testosterone is as effective as BMP-2 in promoting the healing of critical-size segmental defects and that combination therapy with testosterone and BMP-2 is superior to single therapy. Results of this study may provide a foundation to develop a cost effective and efficient therapeutic modality for treatment of bone fractures with segmental defects. PMID:23940550
DOE Office of Scientific and Technical Information (OSTI.GOV)
John F. Schabron; A. Troy Pauli; Joseph F. Rovani Jr.
The dispersed particle solution model of petroleum residua structure was used to develop predictors for pyrolytic coke formation. Coking Indexes were developed in prior years that measure how near a pyrolysis system is to coke formation during the coke formation induction period. These have been demonstrated to be universally applicable for residua regardless of the source of the material. Coking onset is coincidental with the destruction of the ordered structure and the formation of a multiphase system. The amount of coke initially formed appears to be a function of the free solvent volume of the original residua. In the currentmore » work, three-dimensional coke make predictability maps were developed at 400 C, 450 C, and 500 C (752 F, 842 F, and 932 F). These relate residence time and free solvent volume to the amount of coke formed at a particular pyrolysis temperature. Activation energies for two apparent types of zero-order coke formation reactions were estimated. The results provide a new tool for ranking residua, gauging proximity to coke formation, and predicting initial coke make tendencies.« less
Chang, Larry William; Kadam, Dileep B; Sangle, Shashi; Narayanan, Shivakumar; Borse, Rohidas T; McKenzie-White, Jane; Bowen, Craig W; Sisson, Stephen D; Bollinger, Robert C
2012-01-01
Distance learning is an important tool for training HIV health workers. However, there is limited evidence on design and evaluation of distance learning HIV curricula and tools. We therefore designed, implemented, and evaluated a distance learning course on HIV management for clinical care providers in India. After course completion, participant scores rose significantly from a pretest (78.4% mean correct) compared with the posttest (87.5%, P < .001). After course completion, participants were more likely to be confident in starting an initial antiretroviral (ARV) regimen, understanding ARV toxicities, encouraging patient adherence, diagnosing immune reconstitution syndrome, and monitoring patients on ARV medications (P ≤ .05). All participants (100%) strongly agreed/agreed that they would recommend this course to others, and most of them (96%) strongly agreed/agreed that they would take a course in this format again. A pragmatic approach to HIV curriculum development and evaluation resulted in reliable learning outcomes, as well as learner satisfaction and improvement in knowledge.
Levac, Danielle; Glegg, Stephanie M N; Camden, Chantal; Rivard, Lisa M; Missiuna, Cheryl
2015-04-01
The knowledge-to-practice gap in rehabilitation has spurred knowledge translation (KT) initiatives aimed at promoting clinician behavior change and improving patient care. Online KT resources for physical therapists and other rehabilitation clinicians are appealing because of their potential to reach large numbers of individuals through self-paced, self-directed learning. This article proposes best practice recommendations for developing online KT resources that are designed to translate evidence into practice. Four recommendations are proposed with specific steps in the development, implementation, and evaluation process: (1) develop evidence-based, user-centered content; (2) tailor content to online format; (3) evaluate impact; and (4) share results and disseminate knowledge. Based on KT evidence and instructional design principles, concrete examples are provided along with insights gained from experiences in creating and evaluating online KT resources for physical therapists. In proposing these recommendations, the next steps for research are suggested, and others are invited to contribute to the discussion. © 2015 American Physical Therapy Association.
Role of glutathione S-transferase Pi in cisplatin-induced nephrotoxicity.
Townsend, Danyelle M; Tew, Kenneth D; He, Lin; King, Jarrod B; Hanigan, Marie H
2009-02-01
One of the dose-limiting toxicities of cisplatin is nephrotoxicity. Renal toxicity is localized to quiescent proximal tubule cells, where the formation of DNA-adducts cannot account for the dose-limiting toxicity. Our earlier results have shown that a glutathione conjugate of cisplatin is metabolized to a nephrotoxicant via gamma-glutamyl transpeptidase (GGT) and a cysteine S-conjugate beta-lyase. The present study was designed to evaluate the potential role of glutathione S-transferase Pi (GSTP) in the initial steps of the bioactivation of cisplatin. Wild-type mice and mice deficient in both murine GSTP genes (GstP1/P2) were treated with cisplatin. Toxicity in both male and female mice was evaluated 5 days after treatment and renal damage was most severe in wild-type male mice. Wild-type males have approximately 10-fold higher levels of GSTP expression in the liver than females, suggesting that hepatic GSTP in the wild-type males contributed to the formation of the nephrotoxic platinum-glutathione conjugate. In GstP1/P2 null mice the gender difference in toxicity was eliminated. Our data show that GSTP expression is a determinant in cisplatin-induced nephrotoxicity and its levels contribute to sex-dependent differences.
Role of Glutathione S-Transferase Pi in Cisplatin Induced Nephrotoxicity
Townsend, Danyelle M.; Tew, Kenneth D.; He, Lin; King, Jarrod B.; Hanigan, Marie H.
2009-01-01
SUMMARY One of the dose-limiting toxicities of cisplatin is nephrotoxicity. Renal toxicity is localized to quiescent proximal tubule cells, where the formation of DNA-adducts cannot account for the dose-limiting toxicity. Our earlier results have shown that a glutathione-conjugate of cisplatin is metabolized to a nephrotoxicant via gamma-glutamyltranspeptidase (GGT) and a cysteine S-conjugate beta-lyase. The present study was designed to evaluate the potential role of glutathione-S-transferase Pi (GSTP) in the initial steps of the bioactivation of cisplatin. Wild-type mice and mice deficient in both murine GSTP genes (GstP1/P2) were treated with cisplatin. Toxicity in both male and female mice was evaluated 5 days after treatment and renal damage was most severe in wild-type male mice. Wild-type males have ~10-fold higher levels of GSTP expression in the liver than females, suggesting that hepatic GSTP in the wild-type males contributed to the formation of the nephrotoxic platinum-glutathione conjugate. In GstP1/P2 null mice the gender difference in toxicity was eliminated. Our data show that GSTP expression is a determinant in cisplatin-induced nephrotoxicity and its levels contribute to sex-dependent differences. PMID:18819770
Kelay, Tanika; Chan, Kah Leong; Ako, Emmanuel; Yasin, Mohammad; Costopoulos, Charis; Gold, Matthew; Kneebone, Roger K; Malik, Iqbal S; Bello, Fernando
2017-01-01
Distributed Simulation is the concept of portable, high-fidelity immersive simulation. Here, it is used for the development of a simulation-based training programme for cardiovascular specialities. We present an evidence base for how accessible, portable and self-contained simulated environments can be effectively utilised for the modelling, development and testing of a complex training framework and assessment methodology. Iterative user feedback through mixed-methods evaluation techniques resulted in the implementation of the training programme. Four phases were involved in the development of our immersive simulation-based training programme: ( 1) initial conceptual stage for mapping structural criteria and parameters of the simulation training framework and scenario development ( n = 16), (2) training facility design using Distributed Simulation , (3) test cases with clinicians ( n = 8) and collaborative design, where evaluation and user feedback involved a mixed-methods approach featuring (a) quantitative surveys to evaluate the realism and perceived educational relevance of the simulation format and framework for training and (b) qualitative semi-structured interviews to capture detailed feedback including changes and scope for development. Refinements were made iteratively to the simulation framework based on user feedback, resulting in (4) transition towards implementation of the simulation training framework, involving consistent quantitative evaluation techniques for clinicians ( n = 62). For comparative purposes, clinicians' initial quantitative mean evaluation scores for realism of the simulation training framework, realism of the training facility and relevance for training ( n = 8) are presented longitudinally, alongside feedback throughout the development stages from concept to delivery, including the implementation stage ( n = 62). Initially, mean evaluation scores fluctuated from low to average, rising incrementally. This corresponded with the qualitative component, which augmented the quantitative findings; trainees' user feedback was used to perform iterative refinements to the simulation design and components (collaborative design), resulting in higher mean evaluation scores leading up to the implementation phase. Through application of innovative Distributed Simulation techniques, collaborative design, and consistent evaluation techniques from conceptual, development, and implementation stages, fully immersive simulation techniques for cardiovascular specialities are achievable and have the potential to be implemented more broadly.
NASA Astrophysics Data System (ADS)
Dafflon, B.; Wu, Y.; Hubbard, S. S.; Birkholzer, J. T.; Daley, T. M.; Pugh, J. D.; Peterson, J.; Trautz, R. C.
2011-12-01
A risk factor of CO2 storage in deep geological formations includes its potential to leak into shallow formations and impact groundwater geochemistry and quality. In particular, CO2 decreases groundwater pH, which can potentially mobilize naturally occurring trace metals and ions commonly absorbed to or contained in sediments. Here, geophysical studies (primarily complex electrical method) are being carried out at both laboratory and field scales to evaluate the sensitivity of geophysical methods for monitoring dissolved CO2 distribution and geochemical transformations that may impact water quality. Our research is performed in association with a field test that is exploring the effects of dissolved CO2 intrusion on groundwater geochemistry. Laboratory experiments using site sediments (silica sand and some fraction of clay minerals) and groundwater were initially conducted under field relevant CO2 partial pressures (pCO2). A significant pH drop was observed with inline sensors with concurrent changes in fluid conductivity caused by CO2 dissolution. Electrical resistivity and electrical phase responses correlated well with the CO2 dissolution process at various pCO2. Specifically, resistivity decreased initially at low pCO2 condition resulting from CO2 dissolution followed by a slight rebound because of the transition of bicarbonate into non-dissociated carbonic acid at lower pH slightly reducing the total concentration of dissociated species. Continuous electrical phase decreases were also observed, which are interpreted to be driven by the decrease of surface charge density (due to the decrease of pH, which approaches the PZC of the sediments). In general, laboratory experiments revealed the sensitivity of electrical signals to CO2 intrusion into groundwater formations and can be used to guide field data interpretation. Cross well complex electrical data are currently being collected periodically throughout a field experiment involving the controlled release of dissolved CO2 into groundwater. The objective of the geophysical cross well monitoring effort is to evaluate the sensitivity of complex electrical methods to dissolved CO2 at the field scale. Here, we report on the ability to translate laboratory-based petrophysical information from lab to field scales, and on the potential of field complex electrical methods for remotely monitoring CO2-induced geochemical transformations.
Start-up of an anaerobic fluidized bed reactor treating synthetic carbohydrate rich wastewater.
Yeshanew, Martha M; Frunzo, Luigi; Luongo, Vincenzo; Pirozzi, Francesco; Lens, Piet N L; Esposito, Giovanni
2016-12-15
The present work studied the start-up process of a mesophilic (37 ± 2 °C) anaerobic fluidized bed reactor (AFBR) operated at a hydraulic retention time (HRT) of 20 days using synthetic carbohydrate rich wastewater. Anox Kaldness-K1 carriers were used as biofilm carrier material. The reactor performance and biofilm formation were evaluated during the process. The start-up process at lower liquid recirculation flow rate enhanced the biofilm formation and reactor performance. The organic substrate composition had a major impact on early colonization of methanogenic archaea onto the surface of the Kaldness carriers during the start-up process. Specific organic substrates favouring the growth of methanogenic archaea, such as acetate, are preferred in order to facilitate the subsequent biofilm formation and AFBR start-up. The supply of 'bio-available' nutrients and trace elements, in particular iron, had an important role on optimal methanogenic activity and speeding-up of the biofilm development on the Kaldness carriers. This paper provides possible strategies to optimize the various operational parameters that influence the initial biofilm formation and development in an AFBR and similar high rate anaerobic reactors, hence can be used to reduce the long time required for process start-up. Copyright © 2016 Elsevier Ltd. All rights reserved.
ENVIROMENTALLY BENIGN MITIGATION OF MICROBIOLOGICALLY INFLUENCED CORROSION (MIC)
DOE Office of Scientific and Technical Information (OSTI.GOV)
J. Robert Paterek; Gemma Husmillo; Amrutha Daram
The overall program objective is to develop and evaluate environmentally benign agents or products that are effective in the prevention, inhibition, and mitigation of microbially influenced corrosion (MIC) in the internal surfaces of metallic natural gas pipelines. The goal is to develop one or more environmentally benign (a.k.a. ''green'') products that can be applied to maintain the structure and dependability of the natural gas infrastructure. The technical approach for this quarter includes the application of the method of fractionation of the extracts by high performance liquid chromatography (HPLC); determination of antimicrobial activities of the new extracts and fractions using amore » growth inhibition assay, and evaluation of the extracts' ability to inhibit biofilm formation. We initiated the delivery system for these new biocides in the test cell and in mixtures of foam components and biocides/anti-biofilms. A total of 51 fractions collected by HPLC from crude extracts that were obtained from three varieties of Capsicum sp. (Serrano, Habanero, Chile de Arbol) were subjected to growth inhibition tests against two SRB strains, D. vulgaris and D. desulfuricans. Five fractions showed growth inhibition against both strains while seven inhibited D. desulfuricans only. The crude extracts did not show growth inhibition on both strains but were proven to be potent in preventing the formation of biofilm. Growth inhibition tests of the same set of crude extracts against Comamonas denitrificans did not show positive results. The fractions will be subjected to biofilm inhibition and dissociation assay as well. The delivery system to be evaluated first was foam. The ''foam pig'' components of surfactants and water were tested with the biocide addition. The first chemical and physical parameters to be tested were pH and surfactants. Tests using the fractionated pepper extracts are progressing rapidly. Gas chromatographic analysis on a number of fractions is underway. Involvement of other microorganisms in the tests will be extended. The foam application method has been initiated and is being developed.« less
Fairbanks, Benjamin D.; Schwartz, Michael P.; Bowman, Christopher N.; Anseth, Kristi S.
2009-01-01
Due to mild reaction conditions and temporal and spatial control over material formation, photopolymerization has become a valuable technique for the encapsulation of living cells in three dimensional, hydrated, biomimetic materials. For such applications,2-hydroxy-1-[4-(2-hydroxyethoxy) phenyl]-2-methyl-1-propanone (I2959) is the most commonly used photoinitiator (by virtue of its moderate water solubility), yet this initiator has an absorption spectrum that is poorly matched with wavelengths of light generally regarded as benign to living cells, limiting the rate at which it may initiate polymerization in their presence. In contrast, acylphosphine oxide photoinitiators, generally exhibit absorption spectra at wavelengths suitable for cell encapsulation, yet commercially available initiators of this class have low water solubility. Here, a water soluble lithium acylphosphinate salt is evaluated for its ability to polymerize diacrylated poly(ethylene glycol) (PEGDA) monomers rapidly into hydrogels, while maintaining high viability during direct encapsulation of cells. Through rheometric measurements, the time to reach gelation of a PEGDA solution with the phosphinate initiator is one tenth the time for that using I2959 at similar concentrations, when exposed to 365 nm light. Further, polymerization with the phosphinate initiator at 405 nm visible light exposure is achieved with low initiator concentrations and light intensities, precluded in polymerizations initiated with I2959 by its absorbance profile. When examined 24 hours after encapsulation, survival rates of human neonatal fibroblasts encapsulated in hydrogels polymerized with the phosphinate initiator exceed 95%, demonstrating the cytocompatibility of this initiating system. PMID:19783300
Bringolf, Karamie R.; Lawton, Katherine K.; McGuirt, Jared T.; Wall-Bassett, Elizabeth; Morgan, Jo; Laska, Melissa Nelson; Sharkey, Joseph R.
2013-01-01
Introduction Obesity prevalence in the rural United States is higher than in urban or suburban areas, perhaps as a result of the food environment. Because rural residents live farther from supermarkets than their urban- and suburban-dwelling counterparts, they may be more reliant on smaller corner stores that offer fewer healthful food items. Methods As part of a Communities Putting Prevention to Work (CPPW) healthy corner store initiative, we reviewed audit tools in the fall of 2010 to measure the consumer food environment in eastern North Carolina and chose the NEMS-S-Rev (Nutrition Environment Measures Survey-Stores-Revised) to assess 42 food stores. During the spring and summer of 2011, 2 trained graduate assistants audited stores, achieving interrater reliability of at least 80%. NEMS-S-Rev scores of stores in rural versus urban areas were compared. Results Overall, healthful foods were less available and of lower quality in rural areas than in urban areas. NEMS-S-Rev scores indicated that healthful foods were more likely to be available and had similar pricing and quality in rural corner stores than in urban corner stores. Conclusion Food store audit data provided a baseline to implement and evaluate a CPPW healthy corner store initiative in Pitt County. This work serves as a case study, providing lessons learned for engaging community partners when conducting rural food store audits. PMID:23866165
Patel, Sapana R; Margolies, Paul J; Covell, Nancy H; Lipscomb, Cristine; Dixon, Lisa B
2018-01-01
Implementation science lacks a systematic approach to the development of learning strategies for online training in evidence-based practices (EBPs) that takes the context of real-world practice into account. The field of instructional design offers ecologically valid and systematic processes to develop learning strategies for workforce development and performance support. This report describes the application of an instructional design framework-Analyze, Design, Develop, Implement, and Evaluate (ADDIE) model-in the development and evaluation of e-learning modules as one strategy among a multifaceted approach to the implementation of individual placement and support (IPS), a model of supported employment for community behavioral health treatment programs, in New York State. We applied quantitative and qualitative methods to develop and evaluate three IPS e-learning modules. Throughout the ADDIE process, we conducted formative and summative evaluations and identified determinants of implementation using the Consolidated Framework for Implementation Research (CFIR). Formative evaluations consisted of qualitative feedback received from recipients and providers during early pilot work. The summative evaluation consisted of levels 1 and 2 (reaction to the training, self-reported knowledge, and practice change) quantitative and qualitative data and was guided by the Kirkpatrick model for training evaluation. Formative evaluation with key stakeholders identified a range of learning needs that informed the development of a pilot training program in IPS. Feedback on this pilot training program informed the design document of three e-learning modules on IPS: Introduction to IPS, IPS Job development, and Using the IPS Employment Resource Book . Each module was developed iteratively and provided an assessment of learning needs that informed successive modules. All modules were disseminated and evaluated through a learning management system. Summative evaluation revealed that learners rated the modules positively, and self-report of knowledge acquisition was high (mean range: 4.4-4.6 out of 5). About half of learners indicated that they would change their practice after watching the modules (range: 48-51%). All learners who completed the level 1 evaluation demonstrated 80% or better mastery of knowledge on the level 2 evaluation embedded in each module. The CFIR was used to identify implementation barriers and facilitators among the evaluation data which facilitated planning for subsequent implementation support activities in the IPS initiative. Instructional design approaches such as ADDIE may offer implementation scientists and practitioners a flexible and systematic approach for the development of e-learning modules as a single component or one strategy in a multifaceted approach for training in EBPs.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Deibler, Lisa Anne; Brown, Arthur; Puskar, Joseph D.
Drawn 304L stainless steel tubing was subjected to 42 different annealing heat treatments with the goal of initializing a microstructural model to select a heat treatment to soften the tubing from a hardness of 305 Knoop to 225–275 Knoop. The amount of recrystallization and grain size caused by 18 heat treatments were analyzed via optical microscopy and image analysis, revealing the full range of recrystallization from 0 to 100%. The formation of carbides during the longer duration and higher-temperature heat treatments was monitored via transmission electron microscope evaluation. The experimental results informed a model which includes recovery, recrystallization, and grainmore » growth to predict microstructure and hardness. After initialization of the model, it was able to predict hardness with a R 2 value of 0.95 and recrystallization with an R 2 value of 0.99. As a result, the model was then utilized in the design and testing of a heat treatment to soften the tubing.« less
Wallace, Carolyn M; Legro, Marcia W
2008-01-01
Background Implementation of research into practice in health care systems is a challenging and often unsuccessful endeavor. The United States Department of Veterans Affairs (VA) Quality Enhancement Research Initiative (QUERI) research teams include formative evaluations (FE) in their action-oriented VA implementation projects to identify critical information about the processes of implementation that can guide adjustments to project activities, in order to better meet project goals. This article describes the development and use of FE in an action-oriented implementation research project. Methods This two-year action-oriented implementation research project was conducted at 23 VA Spinal Cord Injury (SCI) Centers, and targeted patients, staff and the system of care, such as administration and information technology. Data for FE were collected by electronic and paper surveys, semi-structured and open-ended interviews, notes during conference calls, and exchange of e-mail messages. Specific questions were developed for each intervention (designed to improve vaccination rates for influenza in veterans with spinal cord injury and disorder); informants were selected for their knowledge of interventions and their use in SCI Centers. Results Data from FE were compiled separately for each intervention to describe barriers to progress and guide adjustments to implementation activities. These data addressed the processes of implementing the interventions, problem-solving activities and the status of interventions at SCI Centers. Conclusion Formative evaluations provided the project team with a broad view of the processes of implementing multi-targeted interventions as well as the evolving status of the related best practice. Using FE was useful, although the challenges of conducting FE for non-field researchers should be addressed. Work is needed to develop methods for conducting FE across multiple sites, as well as acknowledging variations in local contexts that affect implementation of interventions. PMID:18430201
Thymoquinone recovers learning function in a rat model of Alzheimer’s disease
Poorgholam, Parvin; Yaghmaei, Parichehreh; Hajebrahimi, Zahra
2018-01-01
Objective: Alzheimer's disease is a neurodegenerative disorder characterized by accumulation of amyloid beta in the hippocampus. In recent decades, herbal medicine has been widely used to treat many neurodegenerative disorders,as in comparison to conventional drugs, herbal remedies exert minimal side effects. Here, the effects of thymoquinone, as the main active component of Nigella sativa, on passive avoidance memory in rat model of Alzheimer’s disease, were evaluated. Materials and Methods: Hippocampal injection of amyloid beta (Aβ) was used to induce Alzheimer’s disease in male Wistar rats, followed by intra peritoneal administrations of 5 and 10 mg/kg thymoquinone on a daily basis for 4 weeks. Animals were subjected to fear learning behavior in passive avoidance test and histopathological analysis of the hippocampus was done. Shuttle box test was used to evaluate the condition studying memory. Thioflavin-S and Hematoxylin and Eosine staining were done to confirm Aβ plaque formation and to evaluate the effect of thymoquinone on the pyramidal cells in the hippocampal CA1 region. Results: Amyloid beta caused cognitive dysfunction reflected by increasing initial and step-through latency along with plaque formation and degeneration of pyramidal cells in the hippocampus. Thymoquinone administration ameliorated this effect by significant reductions in plaque formation in CA1 region of the hippocampus and increased latency time. It also increased the number of surviving neurons in the hippocampus. Conclusion: It seems that thymoquinone improved learning function in a rat model of Alzheimer’s disease. Thus, thymoquinone could be possibly used as an anti-neurodegenerative agent for protecting hippocampal neurons against neurotoxic effects of Aβ in patients with Alzheimer’s disease. PMID:29881705
JPRS Report, Science & Technology, USSR: Earth Sciences
1988-12-06
Vol 24 No 7, Jul 88] 14 Integral Characteristics of Light Scattering by Large Spherical Particles IE. P. Zege, A. A. Kokhanovskiy; IZVESTIYA AKADEMII...economical that the base not contain a grid model, but the initial contours, represented in vector format, in which case it is called a vector DRM. The...information make it possible to display both screen and vector DRM and from these, retrieve contours in the initial format. The automated forest mapping
Aerobic oxidations catalyzed by chromium corroles.
Mahammed, Atif; Gray, Harry B; Meier-Callahan, Alexandre E; Gross, Zeev
2003-02-05
Oxochromium(V) complexes of 5,10,15-tris(pentafluorophenyl)corrole and brominated derivatives oxygenate substrates (triphenylphosphine and norbornene) with concomitant production of chromium(III). Regeneration of CrVO by reaction of dioxygen with CrIII completes an aerobic catalytic cycle, with very large solvent effects; in acetonitrile, rapid initial turnovers observed initially are shut down by formation of CrIVO, while in toluene, THF, and methanol, relatively slow reactions are further inhibited by product formation.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Hai Huang; Ben Spencer; Jason Hales
2014-10-01
A discrete element Model (DEM) representation of coupled solid mechanics/fracturing and heat conduction processes has been developed and applied to explicitly simulate the random initiations and subsequent propagations of interacting thermal cracks in a ceramic nuclear fuel pellet during initial rise to power and during power cycles. The DEM model clearly predicts realistic early-life crack patterns including both radial cracks and circumferential cracks. Simulation results clearly demonstrate the formation of radial cracks during the initial power rise, and formation of circumferential cracks as the power is ramped down. In these simulations, additional early-life power cycles do not lead to themore » formation of new thermal cracks. They do, however clearly indicate changes in the apertures of thermal cracks during later power cycles due to thermal expansion and shrinkage. The number of radial cracks increases with increasing power, which is consistent with the experimental observations.« less
Star formation in a hierarchical model for Cloud Complexes
NASA Astrophysics Data System (ADS)
Sanchez, N.; Parravano, A.
The effects of the external and initial conditions on the star formation processes in Molecular Cloud Complexes are examined in the context of a schematic model. The model considers a hierarchical system with five predefined phases: warm gas, neutral gas, low density molecular gas, high density molecular gas and protostars. The model follows the mass evolution of each substructure by computing its mass exchange with their parent and children. The parent-child mass exchange depends on the radiation density at the interphase, which is produced by the radiation coming from the stars that form at the end of the hierarchical structure, and by the external radiation field. The system is chaotic in the sense that its temporal evolution is very sensitive to small changes in the initial or external conditions. However, global features such as the star formation efficience and the Initial Mass Function are less affected by those variations.
Iron(II) Initiation of Lipid and Protein Oxidation in Pork: The Role of Oxymyoglobin.
Zhou, Feibai; Jongberg, Sisse; Zhao, Mouming; Sun, Weizheng; Skibsted, Leif H
2016-06-08
Iron(II), added as FeSO4·7H2O, was found to increase the rate of oxygen depletion as detected electrochemically in a pork homogenate from Longissimus dorsi through an initial increase in metmyoglobin formation from oxymyoglobin and followed by formation of primary and secondary lipid oxidation products and protein oxidation as detected as thiol depletion in myofibrillar proteins. Without added iron(II), under the same conditions at 37 °C, oxygen consumption corresponded solely to the slow oxymyoglobin autoxidation. Long-lived myofibrillar protein radicals as detected by ESR spectroscopy in the presence of iron(II) were formed subsequently to oxymyoglobin oxidation, and their level was increased by lipid oxidation when oxygen was completely depleted. Similarly, the time profile for formation of lipid peroxide indicated that oxymyoglobin oxidation initiates both protein oxidation and lipid oxidation.
Gu, Cheng; Liu, Cun; Johnston, Cliff T.; Teppen, Brian J.; Li, Hui; Boyd, Stephen A.
2011-01-01
Octachlorodibenzodioxin (OCDD) forms spontaneously from pentachlorophenol (PCP) on the surfaces of Fe(III)-saturated smectite clay (1). Here, we used in situ FTIR methods and quantum mechanical calculations to determine the mechanism by which this reaction is initiated. As the clay was dehydrated, vibrational spectra showed new peaks that grew and then reversibly disappeared as the clay rehydrated. First principle DFT calculations of hydrated Fe-PCP clusters reproduced these transient FTIR peaks when inner-sphere complexation and concomitant electron transfer produced Fe(II) and PCP radical cations. Thus, our experimental (FTIR) and theoretical (quantum mechanical) results mutually support the hypothesis that OCDD formation on Fe-smectite surfaces is initiated by the reversible formation of metastable PCP radical cations via single electron transfer from PCP to Fe(III). The negatively charged clay surface apparently selects for this reaction mechanism by stabilizing PCP radical cations. PMID:21254769
Correa, Loreto A; Zapata, Beatriz; Samaniego, Horacio; Soto-Gamboa, Mauricio
2013-09-01
Social life involves costs and benefits mostly associated with how individuals interact with each other. The formation of hierarchies inside social groups has evolved as a common strategy to avoid high costs stemming from social interactions. Hierarchical relationships seem to be associated with different features such as body size, body condition and/or age, which determine dominance ability ('prior attributes' hypothesis). In contrast, the 'social dynamic' hypothesis suggests that an initial social context is a determinant in the formation of the hierarchy, more so than specific individual attributes. Hierarchical rank places individuals in higher positions, which presumably increases resource accessibility to their benefit, including opportunities for reproduction. We evaluate the maintenance of hierarchy in a family group of guanacos (Lama guanicoe) and evaluate the possible mechanisms involved in the stability of these interactions and their consequences. We estimate the linearity of social hierarchy and their dynamics. We find evidence of the formation of a highly linear hierarchy among females with males positioned at the bottom of the hierarchy. This hierarchy is not affected by physical characteristics or age, suggesting that it is established only through intra-group interactions. Rank is not related with calves' weight gain either; however, subordinated females, with lower rank, exhibit higher rates of allosuckling. We found no evidence of hierarchical structure in calves suggesting that hierarchical relationship in guanacos could be established during the formation of the family group. Hence, our results suggest that hierarchical dynamics could be related more to social dynamics than to prior attributes. We finally discuss the importance of hierarchies established by dominance and their role in minimizing social costs of interactions. Copyright © 2013 Elsevier B.V. All rights reserved.
Update on the Child's Challenging Behaviour Scale following evaluation using Rasch analysis.
Bourke-Taylor, H M; Pallant, J F; Law, M
2014-03-01
The Child's Challenging Behaviour Scale (CCBS) was designed to measure a mother's rating of her child's challenging behaviours. The CCBS was initially developed for mothers of school-aged children with developmental disability and has previously been shown to have good psychometric properties using classical test theory techniques. The aim of this study was to use Rasch analysis to fully evaluate all aspects of the scale, including response format, item fit, dimensionality and targeting. The sample consisted of 152 mothers of a school-aged child (aged 5-18 years) with a disability. Mothers were recruited via websites and mail-out newsletters through not-for-profit organizations that supported families with disabilities. Respondents completed a survey which included the 11 items of the CCBS. Rasch analysis was conducted on these responses using the RUMM2030 package. Rasch analysis of the CCBS revealed serious threshold disordering for nine of the 11 items, suggesting problems with the 5-point response format used for the scale. The neutral midpoint of the response format was subsequently removed to create a 4-point scale. High levels of local dependency were detected among two pairs of items, resulting in the removal of two items (item 7 and item 1). The final nine-item version of the scale (CCBS Version 2) was unidimensional, well targeted, showed good fit to the Rasch model, and strong internal consistency. To achieve fit to the Rasch model it was necessary to make two modifications to the CCBS scale. The resulting nine-item scale with a 4-point response format showed excellent psychometric properties, supporting its internal validity. © 2013 John Wiley & Sons Ltd.
Mirzazadeh, Azim; Gandomkar, Roghayeh; Hejri, Sara Mortaz; Hassanzadeh, Gholamreza; Koochak, Hamid Emadi; Golestani, Abolfazl; Jafarian, Ali; Jalili, Mohammad; Nayeri, Fatemeh; Saleh, Narges; Shahi, Farhad; Razavi, Seyed Hasan Emami
2016-02-01
The purpose of this study was to utilize the Context, Input, Process and Product (CIPP) evaluation model as a comprehensive framework to guide initiating, planning, implementing and evaluating a revised undergraduate medical education programme. The eight-year longitudinal evaluation study consisted of four phases compatible with the four components of the CIPP model. In the first phase, we explored the strengths and weaknesses of the traditional programme as well as contextual needs, assets, and resources. For the second phase, we proposed a model for the programme considering contextual features. During the process phase, we provided formative information for revisions and adjustments. Finally, in the fourth phase, we evaluated the outcomes of the new undergraduate medical education programme in the basic sciences phase. Information was collected from different sources such as medical students, faculty members, administrators, and graduates, using various qualitative and quantitative methods including focus groups, questionnaires, and performance measures. The CIPP model has the potential to guide policy makers to systematically collect evaluation data and to manage stakeholders' reactions at each stage of the reform in order to make informed decisions. However, the model may result in evaluation burden and fail to address some unplanned evaluation questions.
Cosgrove, J W; Brown, I R
1984-05-01
An initiating cell-free protein synthesis system derived from brain was utilized to demonstrate that the intravenous injection of D-lysergic acid diethylamide (LSD) to rabbits resulted in a lesion at the initiation stage of brain protein synthesis. Three inhibitors of initiation, edeine, poly(I), and aurintricarboxylic acid were used to demonstrate a reduction in initiation-dependent amino acid incorporation in the brain cell-free system. One hour after LSD injection, there was also a measurable decrease in the formation of 40S and 80S initiation complexes in vitro, using either [35S]methionine or [35S]Met-tRNAf. Analysis of the methionine pool size after LSD administration indicated there was no change in methionine levels. Analysis of the formation of initiation complexes in the brain cell-free protein synthesis system prepared 6 h after LSD administration indicated that there was a return to control levels at this time. The effects of LSD on steps in the initiation process are thus reversible.
Formation of massive seed black holes via collisions and accretion
NASA Astrophysics Data System (ADS)
Boekholt, T. C. N.; Schleicher, D. R. G.; Fellhauer, M.; Klessen, R. S.; Reinoso, B.; Stutz, A. M.; Haemmerlé, L.
2018-05-01
Models aiming to explain the formation of massive black hole seeds, and in particular the direct collapse scenario, face substantial difficulties. These are rooted in rather ad hoc and fine-tuned initial conditions, such as the simultaneous requirements of extremely low metallicities and strong radiation backgrounds. Here, we explore a modification of such scenarios where a massive primordial star cluster is initially produced. Subsequent stellar collisions give rise to the formation of massive (104-105 M⊙) objects. Our calculations demonstrate that the interplay among stellar dynamics, gas accretion, and protostellar evolution is particularly relevant. Gas accretion on to the protostars enhances their radii, resulting in an enhanced collisional cross-section. We show that the fraction of collisions can increase from 0.1 to 1 per cent of the initial population to about 10 per cent when compared to gas-free models or models of protostellar clusters in the local Universe. We conclude that very massive objects can form in spite of initial fragmentation, making the first massive protostellar clusters viable candidate birth places for observed supermassive black holes.
Hou, Li; Xie, Jianchun; Zhao, Jian; Zhao, Mengyao; Fan, Mengdie; Xiao, Qunfei; Liang, Jingjing; Chen, Feng
2017-10-01
To explore initial Maillard reaction pathways and mechanisms for maximal formation of meaty flavors in heated cysteine-xylose-glycine systems, model reactions with synthesized initial Maillard intermediates, Gly-Amadori, TTCA (2-threityl-thiazolidine-4-carboxylic acids) and Cys-Amadori, were investigated. Relative relativities were characterized by spectrophotometrically monitoring the development of colorless degradation intermediates and browning reaction products. Aroma compounds formed were determined by solid-phase microextraction combined with GC-MS and GC-olfactometry. Gly-Amadori showed the fastest reaction followed by Cys-Amadori then TTCA. Free glycine accelerated reaction of TTCA, whereas cysteine inhibited that of Gly-Amadori due to association forming relatively stable thiazolidines. Cys-Amadori/Gly had the highest reactivity in development of both meaty flavors and brown products. TTCA/Gly favored yielding meaty flavors, whereas Gly-Amadori/Cys favored generation of brown products. Conclusively, initial formation of TTCA and pathway involving TTCA with glycine were more applicable to efficiently produce processed-meat flavorings in a cysteine-xylose-glycine system. Copyright © 2017 Elsevier Ltd. All rights reserved.
Minero, Claudio; Maurino, Valter; Bono, Francesca; Pelizzetti, Ezio; Marinoni, Angela; Mailhot, Gilles; Carlotti, Maria Eugenia; Vione, Davide
2007-08-01
The effect of selected organic and inorganic compounds, present in snow and cloudwater was studied. Photolysis of solutions of nitrate to nitrite was carried out in the laboratory using a UVB light source. The photolysis and other reactions were then modelled. It is shown that formate, formaldehyde, methanesulphonate, and chloride to a lesser extent, can increase the initial formation rate of nitrite. The effect, particularly significant for formate and formaldehyde, is unlikely to be caused by scavenging of hydroxyl radicals. The experimental data obtained in this work suggest that possible causes are the reduction of nitrogen dioxide and nitrate by radical species formed on photooxidation of the organic compounds. Hydroxyl scavenging by organic and inorganic compounds would not affect the initial formation rate of nitrite, but would protect it from oxidation, therefore, increasing the concentration values reached at long irradiation times. The described processes can be relevant to cloudwater and the quasi-liquid layer on the surface of ice and snow, considering that in the polar regions irradiated snow layers are important sources of nitrous acid to the atmosphere. Formate and (at a lesser extent) formaldehyde are the compounds that play the major role in the described processes of nitrite/nitrous acid photoformation by initial rate enhancement and hydroxyl scavenging.
Investigating the 3-D Subduction Initiation Processes at Transform Faults and Passive Margins
NASA Astrophysics Data System (ADS)
Peng, H.; Leng, W.
2017-12-01
Studying the processes of subduction initiation is a key for understanding the Wilson cycle and improving the theory of plate tectonics. Previous studies investigated subduction initiation with geological synthesis and geodynamic modeling methods, discovering that subduction intends to initiate at the transform faults close to oceanic arcs, and that its evolutionary processes and surface volcanic expressions are controlled by plate strength. However, these studies are mainly conducted with 2-D models, which cannot deal with lateral heterogeneities of crustal thickness and strength along the plate interfaces. Here we extend the 2-D model to a 3-D parallel subduction model with high computational efficiency. With the new model, we study the dynamic controlling factors, morphology evolutionary processes and surface expressions for subduction initiation with lateral heterogeneities of material properties along transform faults and passive margins. We find that lateral lithospheric heterogeneities control the starting point of the subduction initiation along the newly formed trenches and the propagation speed for the trench formation. New subduction tends to firstly initiate at the property changing point along the transform faults or passive margins. Such finds may be applied to explain the formation process of the Izu-Bonin-Mariana (IBM) subduction zone in the western Pacific and the Scotia subduction zone at the south end of the South America. Our results enhance our understanding for the formation of new trenches and help to provide geodynamic modeling explanations for the observed remnant slabs in the upper mantle and the surface volcanic expressions.
Rodriguez-Sanchez, Dariana Graciela; Flores-García, Mirthala; Silva-Platas, Christian; Rizzo, Sheryl; Torre-Amione, Guillermo; De la Peña-Diaz, Aurora; Hernández-Brenes, Carmen; García-Rivas, Gerardo
2015-01-01
Platelets play a pivotal role in physiological hemostasis. However, in coronary arteries damaged by atherosclerosis, enhanced platelet aggregation, with subsequent thrombus formation, is a precipitating factor in acute ischemic events. Avocado pulp (Persea americana) is a good source of bioactive compounds, and its inclusion in the diet as a source of fatty acid has been related to reduced platelet aggregability. Nevertheless, constituents of avocado pulp with antiplatelet activity remain unknown. The present study aims to characterize the chemical nature of avocado constituents with inhibitory effects on platelet aggregation. Centrifugal partition chromatography (CPC) was used as a fractionation and purification tool, guided by an in vitro adenosine diphosphate (ADP), arachidonic acid or collagen-platelet aggregation assay. Antiplatelet activity was initially linked to seven acetogenins that were further purified, and their dose-dependent effects in the presence of various agonists were contrasted. This process led to the identification of Persenone-C (3) as the most potent antiplatelet acetogenin (IC₅₀=3.4 mM) among the evaluated compounds. In vivo evaluations with Persenone A (4) demonstrated potential protective effects against arterial thrombosis (25 mg kg⁻¹ of body weight), as coagulation times increased (2-fold with respect to the vehicle) and thrombus formation was attenuated (71% versus vehicle). From these results, avocado may be referred to as a functional food containing acetogenin compounds that inhibit platelet aggregation with a potential preventive effect on thrombus formation, such as those that occur in ischaemic diseases.
The Initial Physical Conditions of Kepler-36 b and c
NASA Astrophysics Data System (ADS)
Owen, James E.; Morton, Timothy. D.
2016-03-01
The Kepler-36 planetary system consists of two exoplanets at similar separations (0.115 and 0.128 au), which have dramatically different densities. The inner planet has a density consistent with an Earth-like composition, while the outer planet is extremely low density, such that it must contain a voluminous H/He envelope. Such a density difference would pose a problem for any formation mechanism if their current densities were representative of their composition at formation. However, both planets are at close enough separations to have undergone significant evaporation in the past. We constrain the core mass, core composition, initial envelope mass, and initial cooling time of each planet using evaporation models conditioned on their present-day masses and radii, as inferred from Kepler photometry and transit timing analysis. The inner planet is consistent with being an evaporatively stripped core, while the outer planet has retained some of its initial envelope due to its higher core mass. Therefore, both planets could have had a similar formation pathway, with the inner planet having an initial envelope-mass fraction of ≲10% and core mass of ˜4.4 M⊕, while the outer had an initial envelope-mass fraction of the order of 15%-30% and core mass ˜7.3 M⊕. Finally, our results indicate that the outer planet had a long (≳30 Myr) initial cooling time, much longer than would naively be predicted from simple timescale arguments. The long initial cooling time could be evidence for a dramatic early cooling episode such as the recently proposed “boil-off” process.
Tools for Formative Evaluation: Gathering the Information Necessary for Program Improvement
ERIC Educational Resources Information Center
Jayaratne, K. S. U.
2016-01-01
New Extension educators experience a steep learning curve when attempting to develop effective Extension programs. Formative evaluation is helpful to new, and experienced, Extension educators in determining the changes necessary for making programs more effective. Formative evaluation is an essential part of program evaluation. However, its use…
Crack Growth Mechanisms under Anti-Plane Shear in Composite Laminates
NASA Astrophysics Data System (ADS)
Horner, Allison Lynne
The research conducted for this dissertation focuses on determining the mechanisms associated with crack growth in polymer matrix composite laminates subjected to anti-plane shear (mode III) loading. For mode III split-beam test methods were proposed, and initial evaluations were conducted. A single test method was selected for further evaluation. Using this test method, it was determined that the apparent mode III delamination toughness, GIIIc , depended on geometry, which indicated a true material property was not being measured. Transverse sectioning and optical microscopy revealed an array of transverse matrix cracks, or echelon cracks, oriented at approximately 45° and intersecting the plane of the delamination. Subsequent investigations found the echelon array formed prior to the onset of planar delamination advance and that growth of the planar delamination is always coupled to echelon array formation in these specimens. The evolution of the fracture surfaces formed by the echelon array and planar delamination were studied, and it was found that the development was similar to crack growth in homogenous materials subjected to mode III or mixed mode I-III loading, although the composite laminate architecture constrained the fracture surface development differently than homogenous materials. It was also found that, for split-beam specimens such as those used herein, applying an anti-plane shear load results in twisting of the specimen's uncracked region which gives rise to a mixed-mode I-III load condition. This twisting has been related to the apparent mode III toughness as well as the orientation of the transverse matrix cracks. A finite element model was then developed to study the mechanisms of initial echelon array formation. From this, it is shown that an echelon array will develop, but will become self-limiting prior to the onset of planar delamination growth.
A 3-D wellbore simulator (WELLTHER-SIM) to determine the thermal diffusivity of rock-formations
NASA Astrophysics Data System (ADS)
Wong-Loya, J. A.; Santoyo, E.; Andaverde, J.
2017-06-01
Acquiring thermophysical properties of rock-formations in geothermal systems is an essential task required for the well drilling and completion. Wellbore thermal simulators require such properties for predicting the thermal behavior of a wellbore and the formation under drilling and shut-in conditions. The estimation of static formation temperatures also needs the use of these properties for the wellbore and formation materials (drilling fluids and pipes, cements, casings, and rocks). A numerical simulator (WELLTHER-SIM) has been developed for modeling the drilling fluid circulation and shut-in processes of geothermal wellbores, and for the in-situ determination of thermal diffusivities of rocks. Bottomhole temperatures logged under shut-in conditions (BHTm), and thermophysical and transport properties of drilling fluids were used as main input data. To model the thermal disturbance and recovery processes in the wellbore and rock-formation, initial drilling fluid and static formation temperatures were used as initial and boundary conditions. WELLTHER-SIM uses these temperatures together with an initial thermal diffusivity for the rock-formation to solve the governing equations of the heat transfer model. WELLTHER-SIM was programmed using the finite volume technique to solve the heat conduction equations under 3-D and transient conditions. Thermal diffusivities of rock-formations were inversely computed by using an iterative and efficient numerical simulation, where simulated thermal recovery data sets (BHTs) were statistically compared with those temperature measurements (BHTm) logged in some geothermal wellbores. The simulator was validated using a well-documented case reported in the literature, where the thermophysical properties of the rock-formation are known with accuracy. The new numerical simulator has been successfully applied to two wellbores drilled in geothermal fields of Japan and Mexico. Details of the physical conceptual model, the numerical algorithm, and the validation and application results are outlined in this work.
Solid-particle jet formation under shock-wave acceleration.
Rodriguez, V; Saurel, R; Jourdan, G; Houas, L
2013-12-01
When solid particles are impulsively dispersed by a shock wave, they develop a spatial distribution which takes the form of particle jets whose selection mechanism is still unidentified. The aim of the present experimental work is to study particle dispersal with fingering effects in an original quasi-two-dimensional experiment facility in order to accurately extract information. Shock and blast waves are generated in the carrier gas at the center of a granular medium ring initially confined inside a Hele-Shaw cell and impulsively accelerated. With the present experimental setup, the particle jet formation is clearly observed. From fast flow visualizations, we notice, in all instances, that the jets are initially generated inside the particle ring and thereafter expelled outward. This point has not been observed in three-dimensional experiments. We highlight that the number of jets is unsteady and decreases with time. For a fixed configuration, considering the very early times following the initial acceleration, the jet size selection is independent of the particle diameter. Moreover, the influence of the initial overpressure and the material density on the particle jet formation have been studied. It is shown that the wave number of particle jets increases with the overpressure and with the decrease of the material density. The normalized number of jets as a function of the initial ring acceleration shows a power law valid for all studied configurations involving various initial pressure ratios, particle sizes, and particle materials.
NASA Astrophysics Data System (ADS)
Bekki, Kenji
2017-05-01
Most old globular clusters (GCs) in the Galaxy are observed to have internal chemical abundance spreads in light elements. We discuss a new GC formation scenario based on hierarchical star formation within fractal molecular clouds. In the new scenario, a cluster of bound and unbound star clusters ('star cluster complex', SCC) that have a power-law cluster mass function with a slope (β) of 2 is first formed from a massive gas clump developed in a dwarf galaxy. Such cluster complexes and β = 2 are observed and expected from hierarchical star formation. The most massive star cluster ('main cluster'), which is the progenitor of a GC, can accrete gas ejected from asymptotic giant branch (AGB) stars initially in the cluster and other low-mass clusters before the clusters are tidally stripped or destroyed to become field stars in the dwarf. The SCC is initially embedded in a giant gas hole created by numerous supernovae of the SCC so that cold gas outside the hole can be accreted on to the main cluster later. New stars formed from the accreted gas have chemical abundances that are different from those of the original SCC. Using hydrodynamical simulations of GC formation based on this scenario, we show that the main cluster with the initial mass as large as [2-5] × 105 M⊙ can accrete more than 105 M⊙ gas from AGB stars of the SCC. We suggest that merging of hierarchical SSCs can play key roles in stellar halo formation around GCs and self-enrichment processes in the early phase of GC formation.
Growth and evolution of satellites in a Jovian massive disc
NASA Astrophysics Data System (ADS)
Moraes, R. A.; Kley, W.; Vieira Neto, E.
2018-03-01
The formation of satellite systems in circum-planetary discs is considered to be similar to the formation of rocky planets in a proto-planetary disc, especially super-Earths. Thus, it is possible to use systems with large satellites to test formation theories that are also applicable to extrasolar planets. Furthermore, a better understanding of the origin of satellites might yield important information about the environment near the growing planet during the last stages of planet formation. In this work, we investigate the formation and migration of the Jovian satellites through N-body simulations. We simulated a massive, static, low-viscosity, circum-planetary disc in agreement with the minimum mass sub-nebula model prescriptions for its total mass. In hydrodynamic simulations, we found no signs of gaps, therefore type II migration is not expected. Hence, we used analytic prescriptions for type I migration, eccentricity and inclination damping, and performed N-body simulations with damping forces added. Detailed parameter studies showed that the number of final satellites is strong influenced by the initial distribution of embryos, the disc temperature, and the initial gas density profile. For steeper initial density profiles, it is possible to form systems with multiple satellites in resonance while a flatter profile favours the formation of satellites close to the region of the Galilean satellites. We show that the formation of massive satellites such as Ganymede and Callisto can be achieved for hotter discs with an aspect ratio of H/r ˜ 0.15 for which the ice line was located around 30RJ.
Pedrotti, Maria Luiza; Gazeau, Frédéric; Guieu, Cécile
2017-01-01
The evolution of organic carbon export to the deep ocean, under anthropogenic forcing such as ocean warming and acidification, needs to be investigated in order to evaluate potential positive or negative feedbacks on atmospheric CO2 concentrations, and therefore on climate. As such, modifications of aggregation processes driven by transparent exopolymer particles (TEP) formation have the potential to affect carbon export. The objectives of this study were to experimentally assess the dynamics of organic matter, after the simulation of a Saharan dust deposition event, through the measurement over one week of TEP abundance and size, and to evaluate the effects of ocean acidification on TEP formation and carbon export following a dust deposition event. Three experiments were performed in the laboratory using 300 L tanks filled with filtered seawater collected in the Mediterranean Sea, during two ‘no bloom’ periods (spring at the start of the stratification period and autumn at the end of this stratification period) and during the winter bloom period. For each experiment, one of the two tanks was acidified to reach pH conditions slightly below values projected for 2100 (~ 7.6–7.8). In both tanks, a dust deposition event of 10 g m-2 was simulated at the surface. Our results suggest that Saharan dust deposition triggered the abiotic formation of TEP, leading to the formation of organic-mineral aggregates. The amount of particulate organic carbon (POC) exported was proportional to the flux of lithogenic particles to the sediment traps. Depending on the season, the POC flux following artificial dust deposition ranged between 38 and 90 mg m-2 over six experimental days. Such variability is likely linked to the seasonal differences in the quality and quantity of TEP-precursors initially present in seawater. Finally, these export fluxes were not significantly different at the completion of the three experiments between the two pH conditions. PMID:28212418
Louis, Justine; Pedrotti, Maria Luiza; Gazeau, Frédéric; Guieu, Cécile
2017-01-01
The evolution of organic carbon export to the deep ocean, under anthropogenic forcing such as ocean warming and acidification, needs to be investigated in order to evaluate potential positive or negative feedbacks on atmospheric CO2 concentrations, and therefore on climate. As such, modifications of aggregation processes driven by transparent exopolymer particles (TEP) formation have the potential to affect carbon export. The objectives of this study were to experimentally assess the dynamics of organic matter, after the simulation of a Saharan dust deposition event, through the measurement over one week of TEP abundance and size, and to evaluate the effects of ocean acidification on TEP formation and carbon export following a dust deposition event. Three experiments were performed in the laboratory using 300 L tanks filled with filtered seawater collected in the Mediterranean Sea, during two 'no bloom' periods (spring at the start of the stratification period and autumn at the end of this stratification period) and during the winter bloom period. For each experiment, one of the two tanks was acidified to reach pH conditions slightly below values projected for 2100 (~ 7.6-7.8). In both tanks, a dust deposition event of 10 g m-2 was simulated at the surface. Our results suggest that Saharan dust deposition triggered the abiotic formation of TEP, leading to the formation of organic-mineral aggregates. The amount of particulate organic carbon (POC) exported was proportional to the flux of lithogenic particles to the sediment traps. Depending on the season, the POC flux following artificial dust deposition ranged between 38 and 90 mg m-2 over six experimental days. Such variability is likely linked to the seasonal differences in the quality and quantity of TEP-precursors initially present in seawater. Finally, these export fluxes were not significantly different at the completion of the three experiments between the two pH conditions.
Anionic Photopolymerization of Methyl-2-Cyanoacrylate and Simultaneous Color Formation
2000-11-15
Anionic polymerization of methyl 2-cyanoacrylate initiated by photoinduced heterolysis of crystal violet leuconitrile (CVCN) and of malachite green leucohydroxide (MGOH) is demonstrated. Polymerization is accompanied by color formation.
Schmid, Michael; Kulli, Sandra; Schneeberger, Kerstin; Naskova, Javorka; Knøchel, Susanne; Ahrens, Christian H.
2017-01-01
ABSTRACT We tested the biofilm formation potential of 30 heat-resistant and 6 heat-sensitive Escherichia coli dairy isolates. Production of curli and cellulose, static biofilm formation on polystyrene (PS) and stainless steel surfaces, biofilm formation under dynamic conditions (Bioflux), and initial adhesion rates (IAR) were evaluated. Biofilm formation varied greatly between strains, media, and assays. Our results highlight the importance of the experimental setup in determining biofilm formation under conditions of interest, as correlation between different assays was often not a given. The heat-resistant, multidrug-resistant (MDR) strain FAM21845 showed the strongest biofilm formation on PS and the highest IAR and was the only strain that formed significant biofilms on stainless steel under conditions relevant to the dairy industry, and it was therefore fully sequenced. Its chromosome is 4.9 Mb long, and it harbors a total of five plasmids (147.2, 54.2, 5.8, 2.5, and 1.9 kb). The strain carries a broad range of genes relevant to antimicrobial resistance and biofilm formation, including some on its two large conjugative plasmids, as demonstrated in plate mating assays. IMPORTANCE In biofilms, cells are embedded in an extracellular matrix that protects them from stresses, such as UV radiation, osmotic shock, desiccation, antibiotics, and predation. Biofilm formation is a major bacterial persistence factor of great concern in the clinic and the food industry. Many tested strains formed strong biofilms, and especially strains such as the heat-resistant, MDR strain FAM21845 may pose a serious issue for food production. Strong biofilm formation combined with diverse resistances (some encoded on conjugative plasmids) may allow for increased persistence, coselection, and possible transfer of these resistance factors. Horizontal gene transfer may conceivably occur in the food production setting or the gastrointestinal tract after consumption. PMID:28550056
Marti, Roger; Schmid, Michael; Kulli, Sandra; Schneeberger, Kerstin; Naskova, Javorka; Knøchel, Susanne; Ahrens, Christian H; Hummerjohann, Jörg
2017-08-01
We tested the biofilm formation potential of 30 heat-resistant and 6 heat-sensitive Escherichia coli dairy isolates. Production of curli and cellulose, static biofilm formation on polystyrene (PS) and stainless steel surfaces, biofilm formation under dynamic conditions (Bioflux), and initial adhesion rates (IAR) were evaluated. Biofilm formation varied greatly between strains, media, and assays. Our results highlight the importance of the experimental setup in determining biofilm formation under conditions of interest, as correlation between different assays was often not a given. The heat-resistant, multidrug-resistant (MDR) strain FAM21845 showed the strongest biofilm formation on PS and the highest IAR and was the only strain that formed significant biofilms on stainless steel under conditions relevant to the dairy industry, and it was therefore fully sequenced. Its chromosome is 4.9 Mb long, and it harbors a total of five plasmids (147.2, 54.2, 5.8, 2.5, and 1.9 kb). The strain carries a broad range of genes relevant to antimicrobial resistance and biofilm formation, including some on its two large conjugative plasmids, as demonstrated in plate mating assays. IMPORTANCE In biofilms, cells are embedded in an extracellular matrix that protects them from stresses, such as UV radiation, osmotic shock, desiccation, antibiotics, and predation. Biofilm formation is a major bacterial persistence factor of great concern in the clinic and the food industry. Many tested strains formed strong biofilms, and especially strains such as the heat-resistant, MDR strain FAM21845 may pose a serious issue for food production. Strong biofilm formation combined with diverse resistances (some encoded on conjugative plasmids) may allow for increased persistence, coselection, and possible transfer of these resistance factors. Horizontal gene transfer may conceivably occur in the food production setting or the gastrointestinal tract after consumption. Copyright © 2017 Marti et al.
Massive Infrared-Quiet Dense Cores: Unveiling the Initial Conditions of High-Mass Star Formation
NASA Astrophysics Data System (ADS)
Motte, F.; Bontemps, S.; Schneider, N.; Schilke, P.; Menten, K. M.
2008-05-01
As Th. Henning said at the conference, cold precursors of high-mass stars are now ``hot topics''. We here propose some observational criteria to identify massive infrared-quiet dense cores which can host the high-mass analogs of Class~0 protostars and pre-stellar condensations. We also show how far-infrared to millimeter imaging surveys of entire complexes forming OB stars are starting to unveil the initial conditions of high-mass star formation.
Boulet, Louis-Philippe; Borduas, Francine; Bouchard, Jacques; Blais, Johanne; Hargreave, Frederick E; Rouleau, Michel
2007-01-01
OBJECTIVES: To describe an interactive playing card workshop in the communication of asthma guidelines recommendations, and to assess the initial evaluation of this educational tool by family physicians. DESIGN: Family physicians were invited to participate in the workshop by advertisements or personal contacts. Each physician completed a standardized questionnaire on his or her perception of the rules, content and properties of the card game. SETTING: A university-based continuing medical education initiative. PARTICIPANTS: Primary care physicians. MAIN OUTCOME MEASURES: Physicians’ evaluation of the rules, content and usefulness of the program. RESULTS: The game allowed the communication of relevant asthma-related content, as well as experimentation with a different learning format. It also stimulated interaction in a climate of friendly competition. Participating physicians considered the method to be an innovative tool that facilitated reflection, interaction and learning. It generated relevant discussions on how to apply guideline recommendations to current asthma care. CONCLUSIONS: This new, interactive, educational intervention, integrating play and scientific components, was well received by participants. This method may be of value to help integrate current guidelines into current practice, thus facilitating knowledge transfer to caregivers. PMID:18060093
[Monitoring social determinants of health].
Espelt, Albert; Continente, Xavier; Domingo-Salvany, Antonia; Domínguez-Berjón, M Felicitas; Fernández-Villa, Tania; Monge, Susana; Ruiz-Cantero, M Teresa; Perez, Glòria; Borrell, Carme
2016-11-01
Public health surveillance is the systematic and continuous collection, analysis, dissemination and interpretation of health-related data for planning, implementation and evaluation of public health initiatives. Apart from the health system, social determinants of health include the circumstances in which people are born, grow up, live, work and age, and they go a long way to explaining health inequalities. A surveillance system of the social determinants of health requires a comprehensive and social overview of health. This paper analyses the importance of monitoring social determinants of health and health inequalities, and describes some relevant aspects concerning the implementation of surveillance during the data collection, compilation and analysis phases, as well as dissemination of information and evaluation of the surveillance system. It is important to have indicators from sources designed for this purpose, such as continuous records or periodic surveys, explicitly describing its limitations and strengths. The results should be published periodically in a communicative format that both enhances the public's ability to understand the problems that affect them, whilst at the same time empowering the population, with the ultimate goal of guiding health-related initiatives at different levels of intervention. Copyright © 2016 SESPAS. Publicado por Elsevier España, S.L.U. All rights reserved.
Bazzi, Angela R.; Mogro-Wilson, Cristina; Negi, Nalini Junko; Gonzalez, Jennifer M. Reingle; Cano, Miguel Ángel; Castro, Yessenia; Cepeda, Alice
2017-01-01
Hispanics are disproportionately affected by substance use and related health harms yet remain underrepresented across scientific disciplines focused on researching and addressing these issues. An interdisciplinary network of scientists committed to fostering the development of social and biomedical researchers focused on Hispanic substance use and health disparities developed innovative mentoring and career development activities. We conducted a formative evaluation study using anonymous membership and conference feedback data to describe specific mentoring and career development activities developed within the national network. Successful mentoring initiatives and career development activities were infused with cultural and community values supportive of professional integration and persistence. Mentoring initially occurred within an annual national conference and was then sustained throughout the year through formal training programs and informal mentoring networks. Although rigorous evaluation is needed to determine the success of these strategies in fostering long-term career development among scientists conducting Hispanic health and substance use research, this innovative model may hold promise for other groups committed to promoting career development and professional integration and persistence for minority (and non-minority) scientists committed to addressing health disparities. PMID:28804254
Development and initial evaluation of the Clinical Information Systems Success Model (CISSM).
Garcia-Smith, Dianna; Effken, Judith A
2013-06-01
Most clinical information systems (CIS) today are technically sound, but the number of successful implementations of these systems is low. The purpose of this study was to develop and test a theoretically based integrated CIS Success Model (CISSM) from the nurse perspective. Model predictors of CIS success were taken from existing research on information systems acceptance, user satisfaction, use intention, user behavior and perceptions, as well as clinical research. Data collected online from 234 registered nurses in four hospitals were used to test the model. Each nurse had used the Cerner Power Chart Admission Health Profile for at least 3 months. Psychometric testing and factor analysis of the 23-item CISSM instrument established its construct validity and reliability. Initial analysis showed nurses' satisfaction with and dependency on CIS use predicted their perceived CIS use Net Benefit. Further analysis identified Social Influence and Facilitating Conditions as other predictors of CIS user Net Benefit. The level of hospital CIS integration may account for the role of CIS Use Dependency in the success of CIS. Based on our experience, CISSM provides a formative as well as summative tool for evaluating CIS success from the nurse's perspective. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.
Computer-based testing: initial report of extensive use in a medical school curriculum.
Peterson, Michael W; Gordon, Joel; Elliott, Scott; Kreiter, Clarence
2004-01-01
Computer-based digital technology offers many opportunities in medical education. One type of digital technology, computer-based testing (CBT), has potentially wide application in undergraduate, graduate, and continuing medical education. This articles describes the development of CBT in an undergraduate medical curriculum. An early step in evaluating CBT is to be sure that the exam format is measuring the examinees' knowledge and not their comfort level or confidence with the technology. It is, therefore, important that the CBT reproduce or accommodate traditional test-taking behavior. CBT also provides for a number of enhancements not easily achieved with traditional paper-and-pencil exams. These include easier control and editing of exam items, better incorporation of testing into the learning environment using specific feedback, and enhancing the questions by incorporating multimedia. CBT does present some unique challenges in testing security, and this article discusses the approach to the security issues. In addition, before initiating CBT into a medical curriculum, the institution must understand the technical and infrastructure requirements for CBT. By providing a 5-year experience with CBT in the medical curriculum, this article hopes to facilitate discussions among medical educators in its appropriate application and evaluation.
Ma, Xiao-kui; Daugulis, Andrew J
2014-05-01
This study investigated the effects of transformation conditions such as initial pH, the initial concentration of glucose and yeast extract in the medium, and the separate addition of ferulic acid and vanillic acid, on the production of vanillin through an analysis of competing by-product formation by Amycolatopsis sp. ATCC 39116. The extent and nature of by-product formation and vanillin yield were affected by initial pH and different initial concentrations of glucose and yeast extract in the medium, with a high yield of vanillin and high cell density obtained at pH 8.0, 10 g/l glucose, and 8 g/l yeast extract. High concentrations of ferulic acid were found to negatively affect cell density. Additional supplementation of 100 mg/l vanillic acid, a metabolically linked by-product, was found to result in a high concentration of vanillin and guaiacol, an intermediate of vanillin. Via an analysis of the effect of these transformation conditions on competing by-product formation, high concentrations of ferulic acid were transformed with a molar yield to vanillin of 96.1 and 95.2 %, by Amycolatopsis sp. ATCC 39116 and Streptomyces V1, respectively, together with a minor accumulation of by-products. These are among the highest performance values reported in the literature to date for Streptomyces in batch cultures.
Some Mechanisms Leading to the Formation of an Argentinian Dryline
NASA Astrophysics Data System (ADS)
Salio, P. V.; Bechis, H.; Ruiz, J.
2016-12-01
Drylines are boundaries that separate air masses with different moisture content. Although they are known to form in different parts of the world, the most studied, by far, are those who develop in the Great Plains of the United States during the warm season. Drylines are also frequently observed during the austral summer over the eastern slope of the Andes, in central Argentina. These drylines are sometimes associated to convection initiation in the afternoon and evening. Despite the importance of this phenomena for the regional weather and climate, the mechanisms associated with these systems, as well as their importance in convection initiation have not been previously studied. Large-scale to micro-scale formation mechanisms have been documented over the Great Plains, but geographical features of the region are strongly different, presenting new challenges in order to understand the generation processes. In this work an objective and multiparameter dryline identification algorithm is developed and applied to the detection of drylines over central Argentina during two summer seasons. The synoptic and mesoscale environment leading to the formation of a typical dryline observed in this region during January 2016 is also analyzed. The terms of the frontogenesis function, applied to the specific humidity field, are evaluated for this particular case. We found that the shear-deformation term is the main contributor to the dryline genesis, with a smaller contribution of the confluence term. Backward trajectories of air parcels starting at both sides of the dryline are computed, in order to identify the origins of the air masses. The hot, dry air mass south of the dryline appears to have been originated over the Southern Pacific, and experienced subsidence after crossing the Southern Andes elevations. The contrast with a much more humid air mass advancing from subtropical South America sets up the environment for the formation of the dryline.
Limited Effect of Anthropogenic Nitrogen Oxides on Secondary Organic Aerosol Formation
NASA Astrophysics Data System (ADS)
Zheng, Y.; Unger, N.; Hodzic, A.; Knote, C. J.; Tilmes, S.; Emmons, L. K.; Lamarque, J. F.; Yu, P.
2014-12-01
Globally secondary organic aerosol (SOA) is mostly formed from biogenic vegetation emissions and as such is regarded as natural aerosol that cannot be reduced by emission control legislation. However, recent research implies that human activities facilitate SOA formation by affecting the amount of precursor emission, the chemical processing and the partitioning into the aerosol phase. Among the multiple human influences, nitrogen oxides (NO + NO2 = NOx) have been assumed to play a critical role in the chemical formation of low volatile compounds. The goal of this study is to improve the SOA scheme in the global NCAR Community Atmospheric Model version 4 with chemistry (CAM4-Chem) by implementing an updated 4-product Volatility Basis Set (VBS) scheme, and apply it to investigate the impact of anthropogenic NOx on SOA. We first compare three different SOA parameterizations: a 2-product model and the updated VBS model both with and without a SOA aging parameterization. Secondly we evaluate predicted organic aerosol amounts against surface measurement from the Interagency Monitoring of Protected Visual Environments (IMPROVE) network and Aerosol Mass Spectrometer (AMS) measurements from 13 aircraft-based field campaigns. We then perform sensitivity experiments to examine how the SOA loading responds to a 50% reduction in anthropogenic NOx in different regions. We find limited SOA reductions of -2.3%, -5.6% and -4.0% for global, southeastern U.S. and Amazon NOx perturbations, respectively. To investigate the chemical processes in more detail, we also use a simplified box model with the same gas-phase chemistry and gas-aerosol partitioning mechanism as in CAM4-Chem to examine the SOA yields dependence on initial precursor emissions and background NOx level. The fact that SOA formation is almost unaffected by changes in NOx can be largely attributed to buffering in chemical pathways (low- versus high-NOx pathways, OH versus NO3-initiated oxidation) and to offsetting tendencies in the biogenic versus anthropogenic SOA responses.
Rodriguez, Andres; Autio, Wesley R; McLandsborough, Lynne A
2008-01-01
The purpose of this study was to evaluate the effect of surface roughness (Ra) and finish of mechanically polished stainless steel (Ra = 0.26 +/- 0.05, 0.49 +/- 0.10, and 0.69 +/- 0.05 microm) and electropolished stainless steel (Ra = 0.16 +/- 0.06, 0.40 +/- 0.003, and 0.67 +/- 0.02 microm) on Listeria adhesion and biofilm formation. A four-strain cocktail of Listeria monocytogenes was used. Each strain (0.1%) was added to 200 ml of tryptic soy broth (TSB), and coupons were inserted to the mixture for 5 min. For biofilm formation, coupons with adhesive cells were incubated in 1:20 diluted TSB at 32 degrees C for 48 h. The experiment was performed by a randomized block design. Our results show that the level of Listeria present after 48 h of incubation (mean = 7 log CFU/cm2) was significantly higher than after 5 min (mean = 6.0 log CFU/cm2) (P < 0.01). No differences in initial adhesion were seen in mechanically finished (mean = 6.7 log CFU/cm2) when compared with electropolished stainless steel (mean = 6.7 log CFU/cm2) (P > 0.05). Listeria initial adhesion (values ranged from 5.9 to 6.1 log CFU/cm2) or biofilm formation (values ranged from 6.9 to 7.2 log CFU/cm2) was not significantly correlated with Ra values (P > 0.05). Image analysis with an atomic force microscope showed that bacteria did not colonize the complete surface after 48 h but were individual cells or grouped in microcolonies that ranged from 5 to 10 microm in diameter and one to three cell layers in thickness. Exopolymeric substances were observed to be associated with the colonies. According to our results, electropolishing stainless steel does not pose a significant advantage for food sanitation over mechanically finished stainless steel.
The Use of Social Survey Data in the Development of Formative Evaluations.
ERIC Educational Resources Information Center
York, John D.
Evaluators who perform formative evaluations would be well served to apprise themselves of recent survey research in framing formative evaluations. Illustrative examples are used from research into such diverse areas of activity as: the development of identities attached to different forms of modern rock and roll; the rationales that juvenile…
The practical oral care video--evaluation of a dental awareness month initiative.
Chalmers, J M; Robinson, J; Nankivell, N
2005-06-01
A collaborative effort for the Australian Dental Association's Dental Awareness Month in 2002 included the production of 'Practical Oral Care - a video for residential care staff'. This evaluation of the project aimed to profile the video purchasers, evaluate the usefulness and appropriateness of the video and accompanying booklet using a mailed questionnaire, and elicit appropriate and practical themes for future geriatric oral health promotion and research. A national mail-out of evaluation questionnaires was undertaken to all purchasers of the video. Of the 792 purchasers at the time of the project, 294 questionnaires were returned with 83.7 per cent from residential aged care facilities, 12.6 per cent from dental professionals and 3.7 per cent from health educators. The great majority of purchasers agreed or strongly agreed that the booklet was practical and useful, video was the best format, video length was appropriate, content was realistic, the video assisted staff to identify residents at risk for dental problems and better meet their oral care needs, and improved awareness about oral care issues. Analysis of purchasers' comments highlighted the need for the production of videos on more specific practical oral care issues with behaviourally difficult residents and residents with dementia, to be supplemented with a self-directed learning package. The Practical Oral Care video was a successful national collaborative geriatric oral health promotion initiative and provided the opportunity to increase awareness about oral care issues in residential care.
NASA Technical Reports Server (NTRS)
Strahan, Susan E.; Douglass, Anne R.
2004-01-01
The Global Modeling Initiative (GMI) has integrated two 36-year simulations of an ozone recovery scenario with an offline chemistry and tra nsport model using two different meteorological inputs. Physically ba sed diagnostics, derived from satellite and aircraft data sets, are d escribed and then used to evaluate the realism of temperature and transport processes in the simulations. Processes evaluated include barri er formation in the subtropics and polar regions, and extratropical w ave-driven transport. Some diagnostics are especially relevant to sim ulation of lower stratospheric ozone, but most are applicable to any stratospheric simulation. The global temperature evaluation, which is relevant to gas phase chemical reactions, showed that both sets of me teorological fields have near climatological values at all latitudes and seasons at 30 hPa and below. Both simulations showed weakness in upper stratospheric wave driving. The simulation using input from a g eneral circulation model (GMI(GCM)) showed a very good residual circulation in the tropics and Northern Hemisphere. The simulation with inp ut from a data assimilation system (GMI(DAS)) performed better in the midlatitudes than it did at high latitudes. Neither simulation forms a realistic barrier at the vortex edge, leading to uncertainty in the fate of ozone-depleted vortex air. Overall, tracer transport in the offline GML(GCM) has greater fidelity throughout the stratosphere tha n it does in the GMI(DAS)
External front instabilities induced by a shocked particle ring.
Rodriguez, V; Saurel, R; Jourdan, G; Houas, L
2014-10-01
The dispersion of a cylindrical particle ring by a blast or shock wave induces the formation of coherent structures which take the form of particle jets. A blast wave, issuing from the discharge of a planar shock wave at the exit of a conventional shock tube, is generated in the center of a granular medium ring initially confined inside a Hele-Shaw cell. With the present experimental setup, under impulsive acceleration, a solid particle-jet formation is observed in a quasi-two-dimensional configuration. The aim of the present investigation is to observe in detail the formation of very thin perturbations created around the external surface of the dispersed particle layer. By means of fast flow visualization with an appropriate recording window, we focus solely on the first instants during which the external particle ring becomes unstable. We find that the critical area of the destabilization of the external ring surface is constant regardless of the acceleration of the initial layer. Moreover, we observe in detail the external front perturbation wavelength, rendered dimensionless by the initial ring perimeter, and follow its evolution with the initial particle layer acceleration. We report this quantity to be constant regardless of the evolution of the initial particle layer acceleration. Finally, we can reasonably assert that external front perturbations depend solely on the material of the particles.
IRON AND FREE RADICAL OXIDATIONS IN CELL MEMBRANES
Schafer, Freya Q.; Yue Qian, Steven; Buettner, Garry R.
2013-01-01
Brain tissue being rich in polyunsaturated fatty acids, is very susceptible to lipid peroxidation. Iron is well known to be an important initiator of free radical oxidations. We propose that the principal route to iron-mediated lipid peroxidations is via iron-oxygen complexes rather than the reaction of iron with hydrogen peroxide, the Fenton reaction. To test this hypothesis, we enriched leukemia cells (K-562 and L1210 cells) with docosahexaenoic acid (DHA) as a model for brain tissue, increasing the amount of DHA from approximately 3 mole % to 32 mole %. These cells were then subjected to ferrous iron and dioxygen to initiate lipid peroxidation in the presence or absence of hydrogen peroxide. Lipid-derived radicals were detected using EPR spin trapping with α-(4-pyridyl-1-oxide)-N-t-butylnitrone (POBN). As expected, lipid-derived radical formation increases with increasing cellular lipid unsaturation. Experiments with Desferal demonstrate that iron is required for the formation of lipid radicals from these cells. Addition of iron to DHA-enriched L1210 cells resulted in significant amounts of radical formation; radical formation increased with increasing amount of iron. However, the exposure of cells to hydrogen peroxide before the addition of ferrous iron did not increase cellular radical formation, but actually decreased spin adduct formation. These data suggest that iron-oxygen complexes are the primary route to the initiation of biological free radical oxidations. This model proposes a mechanism to explain how catalytic iron in brain tissue can be so destructive. PMID:10872752
Sub 2 nm Particle Characterization in Systems with Aerosol Formation and Growth
NASA Astrophysics Data System (ADS)
Wang, Yang
Aerosol science and technology enable continual advances in material synthesis and atmospheric pollutant control. Among these advances, one important frontier is characterizing the initial stages of particle formation by real time measurement of particles below 2 nm in size. Sub 2 nm particles play important roles by acting as seeds for particle growth, ultimately determining the final properties of the generated particles. Tailoring nanoparticle properties requires a thorough understanding and precise control of the particle formation processes, which in turn requires characterizing nanoparticle formation from the initial stages. The knowledge on particle formation in early stages can also be applied in quantum dot synthesis and material doping. This dissertation pursued two approaches in investigating incipient particle characterization in systems with aerosol formation and growth: (1) using a high-resolution differential mobility analyzer (DMA) to measure the size distributions of sub 2 nm particles generated from high-temperature aerosol reactors, and (2) analyzing the physical and chemical pathways of aerosol formation during combustion. Part. 1. Particle size distributions reveal important information about particle formation dynamics. DMAs are widely utilized to measure particle size distributions. However, our knowledge of the initial stages of particle formation is incomplete, due to the Brownian broadening effects in conventional DMAs. The first part of this dissertation studied the applicability of high-resolution DMAs in characterizing sub 2 nm particles generated from high-temperature aerosol reactors, including a flame aerosol reactor (FLAR) and a furnace aerosol reactor (FUAR). Comparison against a conventional DMA (Nano DMA, Model 3085, TSI Inc.) demonstrated that the increased sheath flow rates and shortened residence time indeed greatly suppressed the diffusion broadening effect in a high-resolution DMA (half mini type). The incipient particle size distributions were discrete, suggesting the formation of stable clusters that may be intermediate phases between initial chemical reactions and downstream particle growth. The evolution of incipient cluster size distributions further provided information on the gaseous precursor reaction kinetics, which matched well with the data obtained through other techniques. Part 2. The size distributions and their evolution measured by the DMAs help explain the physical pathways of aerosol formation. The chemical analysis of the incipient particles is an important counterpart to the existing characterization method. The chemical compositions of charged species were measured online with an atmospheric pressure interface time-of-flight mass spectrometer (APi-TOF). The tandem arrangement of the high-resolution DMA and the APi-TOF realized the simultaneous measurement of the mobility and the mass of combustion-generated natively charged particles, which enabled their chemical and physical formation pathways to be derived. The results showed that the initial stages of particle formation were strongly influenced by chemically ionized species during combustion, and that incipient particles composed of pure oxides did not exist. The effective densities of the incipient particles were much lower than those of bulk materials, due to their amorphous structures and different chemical compositions. Measuring incipient particles with high-resolution DMAs is limited because a DMA classifies charged particles only, while the charging characteristics of sub 2 nm particles are not well understood. The charge fraction of combustion-generated incipient particles was measured by coupling a charged particle remover and a condensation particle counter. A high charge fraction was observed, confirming the strong interaction among chemically ionized species and formed particles. The combustion system was modeled by using a unimodal aerosol dynamics model combined with Fuchs' charging theory, and showed that the charging process indeed affected particle formation dynamics during combustion.
Rodgers, K; Cohn, D; Hotovely, A; Pines, E; Diamond, M P; diZerega, G
1998-03-01
To assess the efficacy of bioresorbable films consisting of various polyethylene glycol 6000 and polylactic acid block copolymers on the formation and reformation of adhesions in rabbit models of adhesion development between the sidewall to the adjacent cecum and bowel. The composition of the different polymers was expressed by the number of monomeric units in the block, namely, ethylene oxide (EO) and lactic acid (LA), respectively. Studies of the efficacy of EO/LA films were conducted in rabbit sidewall adhesion formation studies in the presence and absence of blood and in rabbit adhesion reformation studies. REPEL (Life Medical Sciences, Edison, NJ), a film of EO/LA ratio 3.0 manufactured under commercial conditions, was also tested in these animal models. University-based laboratory. New Zealand white rabbits. Placement of films of various EO/LA ratios at the site of injury to the parietal peritoneum. Adhesion formation and reformation. Films of various EO/LA ratios, Seprafilm (Genzyme, Cambridge, MA) and Interceed (Johnson and Johnson Medical, Arlington, TX) placed over an area of excised sidewall at the time of initial injury were highly efficacious in the prevention of adhesion formation. A film of EO/LA ratio 3.7, in contrast with Interceed, was also shown to maintain maximal efficacy in the reduction of adhesion formation in the presence of blood. Further, a film of EO/LA ratio 3.0 produced under commercial conditions, REPEL, was highly efficacious in reducing adhesion development in the rabbit models of adhesion and reformation. These studies suggest that bioresorbable EO/LA films reduced adhesion development in rabbit models of adhesion formation and reformation.
NASA Technical Reports Server (NTRS)
Steinmetz, G. G.
1986-01-01
The development of an electronic primary flight display format aligned with the aircraft velocity vector, a simulation evaluation comparing this format with an electronic attitude-aligned primary flight display format, and a flight evaluation of the velocity-vector-aligned display format are described. Earlier tests in turbulent conditions with the electronic attitude-aligned display format had exhibited unsteadiness. A primary objective of aligning the display format with the velocity vector was to take advantage of a velocity-vector control-wheel steering system to provide steadiness of display during turbulent conditions. Better situational awareness under crosswind conditions was also achieved. The evaluation task was a curved, descending approach with turbulent and crosswind conditions. Primary flight display formats contained computer-drawn perspective runway images and flight-path angle information. The flight tests were conducted aboard the NASA Transport Systems Research Vehicle (TSRV). Comparative results of the simulation and flight tests were principally obtained from subjective commentary. Overall, the pilots preferred the display format aligned with the velocity vector.
A Test of Two Theories in the Initial Process Stage of Coalition Formation.
ERIC Educational Resources Information Center
Flaherty, John F.; Arenson, Sidney J.
1978-01-01
Males and females participated in a coalition formation procedure by interacting with a computer program that simulated a pachisi game situation. Female partner preference data supported a weighted probability model of coalition formation over a bargaining theory. Male partner preference data did not support either theory. (Author)
NASA Astrophysics Data System (ADS)
Mihara, Ryosuke; Gao, Xu; Kim, Sun-joong; Ueda, Shigeru; Shibata, Hiroyuki; Seok, Min Oh; Kitamura, Shin-ya
2018-02-01
Using a direct observation experimental method, the oxide formation behavior on the surface of Fe-Cr-5 mass pct C-Si alloy baths during decarburization by a top-blown Ar-O2 mixture was studied. The effects of the initial Si and Cr content of the alloy, temperature, and oxygen feed ratio on oxide formation were investigated. The results showed that, for alloys without Si, oxide particles, unstable oxide films, and stable oxide films formed sequentially. The presence of Si in the alloy changed the formation behavior of stable oxide film, and increased the crucial C content when stable oxide film started to form. Increasing the temperature, decreasing the initial Cr content, and increasing the ratio of the diluting gas decreased the critical C content at which a stable oxide film started to form. In addition, the P CO and a_{{{Cr}2 {O}3 }} values at which oxides started to form were estimated using Hilty's equation and the equilibrium relation to understand the formation conditions and the role of each parameter in oxide formation.
Vascular Calcification and Stone Disease: A New Look towards the Mechanism
Yiu, Allen J.; Callaghan, Daniel; Sultana, Razia; Bandyopadhyay, Bidhan C.
2015-01-01
Calcium phosphate (CaP) crystals are formed in pathological calcification as well as during stone formation. Although there are several theories as to how these crystals can develop through the combined interactions of biochemical and biophysical factors, the exact mechanism of such mineralization is largely unknown. Based on the published scientific literature, we found that common factors can link the initial stages of stone formation and calcification in anatomically distal tissues and organs. For example, changes to the spatiotemporal conditions of the fluid flow in tubular structures may provide initial condition(s) for CaP crystal generation needed for stone formation. Additionally, recent evidence has provided a meaningful association between the active participation of proteins and transcription factors found in the bone forming (ossification) mechanism that are also involved in the early stages of kidney stone formation and arterial calcification. Our review will focus on three topics of discussion (physiological influences—calcium and phosphate concentration—and similarities to ossification, or bone formation) that may elucidate some commonality in the mechanisms of stone formation and calcification, and pave the way towards opening new avenues for further research. PMID:26185749
NASA Astrophysics Data System (ADS)
Gray, William J.; McKee, Christopher F.; Klein, Richard I.
2018-01-01
Star-forming molecular clouds are observed to be both highly magnetized and turbulent. Consequently, the formation of protostellar discs is largely dependent on the complex interaction between gravity, magnetic fields, and turbulence. Studies of non-turbulent protostellar disc formation with realistic magnetic fields have shown that these fields are efficient in removing angular momentum from the forming discs, preventing their formation. However, once turbulence is included, discs can form in even highly magnetized clouds, although the precise mechanism remains uncertain. Here, we present several high-resolution simulations of turbulent, realistically magnetized, high-mass molecular clouds with both aligned and random turbulence to study the role that turbulence, misalignment, and magnetic fields have on the formation of protostellar discs. We find that when the turbulence is artificially aligned so that the angular momentum is parallel to the initial uniform field, no rotationally supported discs are formed, regardless of the initial turbulent energy. We conclude that turbulence and the associated misalignment between the angular momentum and the magnetic field are crucial in the formation of protostellar discs in the presence of realistic magnetic fields.
Preliminary Study for a Tetrahedron Formation: Quality Factors and Visualization
NASA Technical Reports Server (NTRS)
Guzman, Jose J.; Schiff, Conrad; Bauer, Frank (Technical Monitor)
2002-01-01
Spacecraft flying in tetrahedron formations are excellent for electromagnetic and plasma studies. The quality of the science recorded is strongly affected by the tetrahedron evolution. This paper is a preliminary study on the computation of quality factors and visualization for a formation of four or five satellites. Four of the satellites are arranged geometrically in a tetrahedron shape. If a fifth satellite is present, it is arbitrarily initialized at the geometric center of the tetrahedron. The fifth satellite could act as a collector or as a spare spacecraft. Tetrahedron natural coordinates are employed for the initialization. The natural orbit evolution is visualized in geocentric equatorial inertial and in geocentric solar magnetospheric coordinates.
Srinivasan, Ramanathan; Santhakumari, Sivasubramanian; Ravi, Arumugam Veera
2017-09-01
Vibrio harveyi is a potent biofilm former, which confers resistance to multiple antimicrobials, disinfectants, chemicals and biocides. The prevalence of biofilm mediated antibiotic resistance among aquatic bacterial pathogens stresses the search for novel alternative approach to treat vibriosis in aquaculture. Exploring suitable therapeutics from natural resources could be a novel area of research. Therefore, this work was executed to evaluate the inhibitory effect of Piper betle ethyl acetate extract (PBE) on bioluminescence production and biofilm formation of V. harveyi. Minimal inhibitory concentration (MIC) of PBE against planktonic V. harveyi was found to be 1600 μg ml -1 ; furthermore, PBE inhibited the quorum sensing (QS) mediated bioluminescence production and biofilm formation in V. harveyi upto 98 and 74% respectively, at its sub-MIC concentration of 400 μg ml -1 without affecting their cell viability. Similar results were obtained for exopolysaccharides production and swimming motility related to biofilm formation of V. harveyi, where PBE reduced EPS production upto 64%. Light and confocal laser scanning microscopic analyses further confirmed that the PBE effectively prevented the initial attachment as well as microcolonies formation of V. harveyi biofilm, when compared to their untreated controls. This study demonstrates the promising antibiofilm activity of PBE and confirms the ethnopharmacological potential of this plant against V. harveyi infections. Copyright © 2017 Elsevier Ltd. All rights reserved.
Sugita, Chihiro; Yamashita, Atsushi; Matsuura, Yunosuke; Iwakiri, Takashi; Okuyama, Nozomi; Matsuda, Shuntaro; Matsumoto, Tomoko; Inoue, Osamu; Harada, Aya; Kitazawa, Takehisa; Hattori, Kunihiro; Shima, Midori; Asada, Yujiro
2013-07-01
Elevated plasma levels of factor VIII (FVIII) are associated with increased risk of deep venous thrombosis. The aim of this study is to elucidate how elevated FVIII levels affect venous thrombus formation and propagation in vivo. We examined rabbit plasma FVIII activity, plasma thrombin generation, whole blood coagulation, platelet aggregation and venous wall thrombogenicity before and one hour after an intravenous infusion of recombinant human FVIII (rFVIII). Venous thrombus induced by the endothelial denudation of rabbit jugular veins was histologically assessed. Thrombus propagation was evaluated as indocyanine green fluorescence intensity. Argatroban, a thrombin inhibitor, and neutralised antibodies for tissue factor (TF), factor XI (FXI), and von Willebrand factor (VWF) were infused before or after thrombus induction to investigate their effects on venous thrombus formation or propagation. Recombinant FVIII (100 IU/kg) increased rabbit plasma FVIII activity two-fold and significantly enhanced whole blood coagulation and total plasma thrombin generation, but did not affect initial thrombin generation time, platelet aggregation and venous wall thrombogenicity. The rFVIII infusion also increased the size of venous thrombus 1 hour after thrombus induction. Argatroban and the antibodies for TF, FXI or VWF inhibited such enhanced thrombus formation and all except TF suppressed thrombus propagation. In conclusion, elevated plasma FVIII levels enhance venous thrombus formation and propagation. Excess thrombin generation by FXI and VWF-mediated FVIII recruitment appear to contribute to the growth of FVIII-driven venous thrombus.
Concurrent Formative Evaluation: Guidelines and Implications for Multimedia Designers.
ERIC Educational Resources Information Center
Northrup, Pamela Taylor
1995-01-01
Discusses formative evaluation for multimedia instruction and presents guidelines for formatively evaluating multimedia instruction concurrent with analysis, design, and development. Data collection criteria that include group involvement, data collection strategies, and information to be gathered are presented, and rapid prototypes and…
Comprehensive planning of data archive in Japanese planetary missions
NASA Astrophysics Data System (ADS)
Yamamoto, Yukio; Shinohara, Iku; Hoshino, Hirokazu; Tateno, Naoki; Hareyama, Makoto; Okada, Naoki; Ebisawa, Ken
Comprehensive planning of data archive in Japanese planetary missions Japan Aerospace Exploration Agency (JAXA) provides HAYABUSA and KAGUYA data as planetary data archives. These data archives, however, were prepared independently. Therefore the inconsistency of data format has occurred, and the knowledge of data archiving activity is not inherited. Recently, the discussion of comprehensive planning of data archive has started to prepare up-coming planetary missions, which indicates the comprehensive plan of data archive is required in several steps. The framework of the comprehensive plan is divided into four items: Preparation, Evaluation, Preservation, and Service. 1. PREPARATION FRAMEWORK Data is classified into several types: raw data, level-0, 1, 2 processing data, ancillary data, and etc. The task of mission data preparation is responsible for instrument teams, but preparations beside mission data and support of data management are essential to make unified conventions and formats over instruments in a mission, and over missions. 2. EVALUATION FRAMEWORK There are two meanings of evaluation: format and quality. The format evaluation is often discussed in the preparation framework. The data quality evaluation which is often called quality assurance (QA) or quality control (QC) must be performed by third party apart from preparation teams. An instrument team has the initiative for the preparation itself, and the third-party group is organized to evaluate the instrument team's activity. 3. PRESERVATION FRAMEWORK The main topic of this framework is document management, archiving structure, and simple access method. The mission produces many documents in the process of the development. Instrument de-velopment is no exception. During long-term development of a mission, many documents are obsoleted and updated repeatedly. A smart system will help instrument team to reduce some troubles of document management and archiving task. JAXA attempts to follow PDS manners to do this management since PDS has highly sophisticated archiving structure. In addition, the access method to archived data must be simple and standard well over a decade. 4. SERVICE FRAMEWORK The service framework including planetary data access protocol, PDAP, has been developed to share a stored data effectively. The sophisticated service framework will work not only for publication data, but also for low-level data. JAXA's data query services is under developed based on PDAP, which means that the low-level data can be published in the same manner as level 2 data. In this presentation, we report the detail structure of these four frameworks adopting upcoming Planet-C, Venus Climate Orbiter, mission.
X-ray insights into star and planet formation.
Feigelson, Eric D
2010-04-20
Although stars and planets form in cold environments, X-rays are produced in abundance by young stars. This review examines the implications of stellar X-rays for star and planet formation studies, highlighting the contributions of NASA's (National Aeronautics and Space Administration) Chandra X-ray Observatory. Seven topics are covered: X-rays from protostellar outflow shocks, X-rays from the youngest protostars, the stellar initial mass function, the structure of young stellar clusters, the fate of massive stellar winds, X-ray irradiation of protoplanetary disks, and X-ray flare effects on ancient meteorites. Chandra observations of star-forming regions often show dramatic star clusters, powerful magnetic reconnection flares, and parsec-scale diffuse plasma. X-ray selected samples of premain sequence stars significantly advance studies of star cluster formation, the stellar initial mass function, triggered star-formation processes, and protoplanetary disk evolution. Although X-rays themselves may not play a critical role in the physics of star formation, they likely have important effects on protoplanetary disks by heating and ionizing disk gases.
X-ray insights into star and planet formation
Feigelson, Eric D.
2010-01-01
Although stars and planets form in cold environments, X-rays are produced in abundance by young stars. This review examines the implications of stellar X-rays for star and planet formation studies, highlighting the contributions of NASA’s (National Aeronautics and Space Administration) Chandra X-ray Observatory. Seven topics are covered: X-rays from protostellar outflow shocks, X-rays from the youngest protostars, the stellar initial mass function, the structure of young stellar clusters, the fate of massive stellar winds, X-ray irradiation of protoplanetary disks, and X-ray flare effects on ancient meteorites. Chandra observations of star-forming regions often show dramatic star clusters, powerful magnetic reconnection flares, and parsec-scale diffuse plasma. X-ray selected samples of premain sequence stars significantly advance studies of star cluster formation, the stellar initial mass function, triggered star-formation processes, and protoplanetary disk evolution. Although X-rays themselves may not play a critical role in the physics of star formation, they likely have important effects on protoplanetary disks by heating and ionizing disk gases. PMID:20404197
Miller, Quin R. S.; Wang, Xiuyu; Kaszuba, John P.; ...
2016-07-18
Laboratory experiments evaluated two shale caprock formations, the Gothic Shale and Marine Tuscaloosa Formation, at conditions relevant to carbon dioxide (CO 2) sequestration. Both rocks were exposed to CO 2-saturated brines at 160°C and 15 MPa for ~45 days. Baseline experiments for both rocks were pressurized with argon to 15 MPa for ~35 days. Varying concentrations of iron, aqueous silica, sulfate, and initial pH decreases coincide with enhanced carbonate and silicate dissolution due to reaction between CO 2-saturated brine and shale. Saturation indices were calculated and activity diagrams were constructed to gain insights into sulfate, silicate, and carbonate mineral stabilities.more » We found that upon exposure to CO 2-saturated brines, the Marine Tuscaloosa Formation appeared to be more reactive than the Gothic Shale. Evolution of aqueous geochemistry in the experiments is consistent with mineral precipitation and dissolution reactions that affect porosity. Finally, this study highlights the importance of tracking fluid chemistry to clarify downhole physicochemical responses to CO 2 injection and subsequent changes in sealing capacity in CO 2 storage and utilization projects.« less
Triratana, T; Kraivaphan, P; Tandhachoon, K; Rustogi, K; Volpe, A R; Petrone, M
1995-01-01
A three-month, double-blind, parallel clinical study was conducted on a population of Thai adults to evaluate the effect of the twice daily use of a commercially available pre-brush mouthrinse on supragingival calculus formation. The mouthrinse test product contained 0.03% triclosan and 0.13% PVM/MA copolymer with the absence of fluoride. The subjects were initially examined for calculus using the Volpe-Manhold procedure. All subjects received an oral prophylaxis and were assigned to the use of either 1) a triclosan-copolymer mouthrinse, or 2) a matching flavored/colored water placebo mouthrinse. Subjects were instructed to rinse twice daily with 10 cc of the assigned mouthrinse for 1 minute, followed by brushing with the provided toothpaste containing fluoride for 45 seconds. After three months of using the assigned mouthrinse, the subjects were reexamined for calculus formation. The results indicated that the subjects using triclosan/copolymer mouthrinse had 23.17% less supragingival calculus than the placebo mouthrinse subjects. This reduction was statistically significant at the 99% or greater (F = 24.35, p<0.001) level of confidence.
Fitzgerald, M M; Kirk, G D; Bristow, C A
2011-05-01
Service user involvement in all levels of healthcare provision is the expectation of UK government policy. Involvement should not only include participation in the planning and delivery of health care but also the exercise of choice and opinions about that care. In practice, however, service user engagement is most often tokenistic, involving post hoc consultation over plans already committed to by services. This paper explores an Occupational Therapy-led initiative to use the Serious Game format to engage low secure service users with serious mental illness in the design, layout and refurbishment of their unit. Among other things how medication was to be dispensed on the new unit was explored by this game and led to significant replanning in response to service user involvement. The game format was found to be a useful tool in facilitating communication between professionals and a traditionally marginalized and powerless client group. It enabled service users to have a voice, it provided a format for that voice to be heard and made possible service-led change in the planning process. © 2010 Blackwell Publishing.
Sustaining Nursing and Midwifery Grand Rounds in a Regional Australian Health Service.
Smyth, Wendy; Abernethy, Gail
2016-07-01
This article reports the success, or otherwise, of strategies implemented to sustain nursing grand rounds in a large regional health service in North Queensland, Australia. Nursing grand rounds had been introduced in late 2010 to increase nurses' engagement with research and evidence-based practice. Although the format, topics, and purpose of grand rounds have changed, attendees continue to positively evaluate each presentation. However, after 5 years, the initiative has expanded and somewhat modified its focus. This article describes these changes and proposes options for the future progression of this professional development activity. J Contin Educ Nurs. 2016;47(7):316-320. Copyright 2016, SLACK Incorporated.
Alternative model of thrust-fault propagation
NASA Astrophysics Data System (ADS)
Eisenstadt, Gloria; de Paor, Declan G.
1987-07-01
A widely accepted explanation for the geometry of thrust faults is that initial failures occur on deeply buried planes of weak rock and that thrust faults propagate toward the surface along a staircase trajectory. We propose an alternative model that applies Gretener's beam-failure mechanism to a multilayered sequence. Invoking compatibility conditions, which demand that a thrust propagate both upsection and downsection, we suggest that ramps form first, at shallow levels, and are subsequently connected by flat faults. This hypothesis also explains the formation of many minor structures associated with thrusts, such as backthrusts, wedge structures, pop-ups, and duplexes, and provides a unified conceptual framework in which to evaluate field observations.
77 FR 42736 - Common Formats for Patient Safety Data Collection and Event Reporting
Federal Register 2010, 2011, 2012, 2013, 2014
2012-07-20
... Safety Databases (NPSD). Since the initial release of the Common Formats in August 2008, AHRQ has.... The inventory includes many systems from the private sector, including prominent academic settings...
Formative Assessment Probes: Is It Erosion or Weathering?
ERIC Educational Resources Information Center
Keeley, Page
2016-01-01
This column focuses on promoting learning through assessment. The formative assessment probe in this month's issue can be used as an initial elicitation before students are introduced to the formal concepts of weathering and erosion.
Degradable borate glass polyalkenoate cements.
Shen, L; Coughlan, A; Towler, M; Hall, M
2014-04-01
Glass polyalkenoate cements (GPCs) containing aluminum-free borate glasses having the general composition Ag2O-Na2O-CaO-SrO-ZnO-TiO2-B2O3 were evaluated in this work. An initial screening study of sixteen compositions was used to identify regions of glass formation and cement compositions with promising rheological properties. The results of the screening study were used to develop four model borate glass compositions for further study. A second round of rheological experiments was used to identify a preferred GPC formulation for each model glass composition. The model borate glasses containing higher levels of TiO2 (7.5 mol %) tended to have longer working times and shorter setting times. Dissolution behavior of the four model GPC formulations was evaluated by measuring ion release profiles as a function of time. All four GPC formulations showed evidence of incongruent dissolution behavior when considering the relative release profiles of sodium and boron, although the exact dissolution profile of the glass was presumably obscured by the polymeric cement matrix. Compression testing was undertaken to evaluate cement strength over time during immersion in water. The cements containing the borate glass with 7.5 mol % TiO2 had the highest initial compressive strength, ranging between 20 and 30 MPa. No beneficial aging effect was observed-instead, the strength of all four model GPC formulations was found to degrade with time.
Chang, Evelyn T; Zulman, Donna M; Asch, Steven M; Stockdale, Susan E; Yoon, Jean; Ong, Michael K; Lee, Martin; Simon, Alissa; Atkins, David; Schectman, Gordon; Kirsh, Susan R; Rubenstein, Lisa V
2018-06-01
Patient-centered medical homes have made great strides providing comprehensive care for patients with chronic conditions, but may not provide sufficient support for patients at highest risk for acute care use. To address this, the Veterans Health Administration (VHA) initiated a five-site demonstration project to evaluate the effectiveness of augmenting the VA's Patient Aligned Care Team (PACT) medical home with PACT Intensive Management (PIM) teams for Veterans at highest risk for hospitalization. Researchers partnered with VHA leadership to design a mixed-methods prospective multi-site evaluation that met leadership's desire for a rigorous evaluation conducted as quality improvement rather than research. We conducted a randomized QI evaluation and assigned high-risk patients to participate in PIM and compared them with high-risk Veterans receiving usual care through PACT. The summative evaluation examines whether PIM: 1) decreases VHA emergency department and hospital use; 2) increases satisfaction with VHA care; 3) decreases provider burnout; and 4) generates positive returns on investment. The formative evaluation aims to support improved care for high-risk patients at demonstration sites and to inform future initiatives for high-risk patients. The evaluation was reviewed by representatives from the VHA Office of Research and Development and the Office of Research Oversight and met criteria for quality improvement. VHA aims to function as a learning organization by rapidly implementing and rigorously testing QI innovations prior to final program or policy development. We observed challenges and opportunities in designing an evaluation consistent with QI standards and operations priorities, while also maintaining scientific rigor. This trial was retrospectively registered at ClinicalTrials.gov on April 3, 2017: NCT03100526. Protocol v1, FY14-17. Copyright © 2018 Elsevier Inc. All rights reserved.
THE FIRST FERMI IN A HIGH ENERGY NUCLEAR COLLISION.
DOE Office of Scientific and Technical Information (OSTI.GOV)
KRASNITZ,A.
1999-08-09
At very high energies, weak coupling, non-perturbative methods can be used to study classical gluon production in nuclear collisions. One observes in numerical simulations that after an initial formation time, the produced partons are on shell, and their subsequent evolution can be studied using transport theory. At the initial formation time, a simple non-perturbative relation exists between the energy and number densities of the produced partons, and a scale determined by the saturated parton density in the nucleus.
2007-04-01
the underlying parameters are available. Standard data format. Battelle, SAGEM Avionics, and Austin Digital, Inc. agreed upon a standard data format...data was initiated at four airlines by SAGEM Avionics beginning January 1, 2006. Transfer was initiated at one airline by Aus- tin Digital, Inc...internal issues have been resolved. As of April 0, 2006, more than 124,000 flights have been transferred to local archive servers by SAGEM and over
[Formative evaluation: experience of the Catalonian family and community medicine teaching units].
Ezquerra Lezcano, Matilde; Bundo Vidiella, Magda; Descarrega Queralt, Ramón; Martín Zurro, Amando; Fores García, Dolores; Fornells Vallès, Josep Maria
2010-04-01
The purpose of this article is to report on the experience in formative evaluation that was carried out in the Catalonian family and community medicine teaching units during the years 2001-2007. This formative evaluation project included the use of several evaluation tools such as, self-listening, video-recording, structured observation of clinical practice, cases by computer and simulated patients. Different resident intakes have participated in the development of the project, as well as their teaching unit tutors and coordinators. This accumulated experience has allowed it to progress into the field of formative evaluation, and to adapt and integrate the activities that were being carried out in a resident portfolio, which in our opinion is the best tool for the formative evaluation of the family medicine resident. Copyright 2009 Elsevier España, S.L. All rights reserved.
Gas potential of the Rome Trough in Kentucky: Results of recent Cambrian exploration
DOE Office of Scientific and Technical Information (OSTI.GOV)
Harris, D.C.; Drahovzal, J.A.
1996-09-01
A recent gas discovery in the Rome Trough suggests the need to re-evaluate the deep Cambrian potential of eastern Kentucky. A new phase of Cambrian exploration began in mid-1994 with a new pool discovery by the Carson Associates No. 1 Kazee well in Elliott County, Ky. This well blew out and initially flowed 11 MMcfd of gas from the upper Conasauga Group/Rome Formation at 6,258 to 6,270 feet. After this discovery, a second exploratory well (the Blue Ridge No. 1Greene) was drilled on a separate structure in Elliott County in late 1995. The Blue Ridge well was temporarily abandoned, butmore » had shows of gas and condensate. In early 1996, Carson Associates offset their initial discovery well with the No. 33 Lawson Heirs well. This activity follows a frustrating exploration history in the Rome Trough that is marked by numerous gas and oil shows, but rare commercial production. Only three single-well pools have produced commercial gas from the trough, including the recent Kazee well. Stratigraphic units below the Cambrian-Ordovician Knox Group in the Rome Trough are dramatically thicker than their equivalents on the shelf to the north. The interval in the trough is thought to include rocks as old as Early Cambrian, consisting of a basal sandstone, equivalents of the Shady/Tomstown Dolomite, the Rome Formation, and the Conasauga Formation. Sandstones and fractured shales have been responsible for most of the production to date, but dolostone intervals may also have potential. Limited seismic data indicate possible fan-delta and basin-floor fan deposits that may have reservoir potential.« less
Su, Yiming; Adeleye, Adeyemi S; Huang, Yuxiong; Sun, Xiaoya; Dai, Chaomeng; Zhou, Xuefei; Zhang, Yalei; Keller, Arturo A
2014-10-15
Nanoscale zerovalent iron (nZVI) has demonstrated high efficacy for treating nitrate or cadmium (Cd) contamination, but its efficiency for simultaneous removal of nitrate and Cd has not been investigated. This study evaluated the reactivity of nZVI to the co-contaminants and by-product formation, employed different catalysts to reduce nitrite yield from nitrate, and examined the transformation of nZVI after reaction. Nitrate reduction resulted in high solution pH, negatively charged surface of nZVI, formation of Fe3O4 (a stable transformation of nZVI), and no release of ionic iron. Increased pH and negative charge contributed to significant increase in Cd(II) removal capacity (from 40 mg/g to 188 mg/g) with nitrate present. In addition, nitrate reduction by nZVI could be catalyzed by Cd(II): while 30% of nitrate was reduced by nZVI within 2 h in the absence of Cd(II), complete nitrate reduction was observed in the presence of 40 mg-Cd/L due to the formation of Cd islands (Cd(0) and CdO) on the nZVI particles. While nitrate was reduced mostly to ammonium when Cd(II) was not present or at Cd(II) concentrations ≥ 40 mg/L, up to 20% of the initial nitrate was reduced to nitrite at Cd(II) concentrations < 40 mg/L. Among nZVI particles doped with 1 wt. % Cu, Ag, or Au, nZVI deposited with 1 wt. % Au reduced nitrite yield to less than 3% of the initial nitrate, while maintaining a high Cd(II) removal capacity. Copyright © 2014 Elsevier Ltd. All rights reserved.
Pereira, Guillermo; Palfner, Götz; Chávez, Daniel; Suz, Laura M; Machuca, Angela; Honrubia, Mario
2013-07-01
The high cost and restricted availability of black truffle spore inoculum for controlled mycorrhiza formation of host trees produced for truffle orchards worldwide encourage the search for more efficient and sustainable inoculation methods that can be applied globally. In this study, we evaluated the potential of the nurse plant method for the controlled inoculation of Quercus cerris and Quercus robur with Tuber melanosporum by mycorrhizal networks in pot cultures. Pine bark compost, adjusted to pH 7.8 by liming, was used as substrate for all assays. Initially, Q. robur seedlings were inoculated with truffle spores and cultured for 12 months. After this period, the plants presenting 74 % mycorrhizal fine roots were transferred to larger containers. Nurse plants were used for two treatments of two different nursling species: five sterilized acorns or five 45-day-old, axenically grown Q. robur or Q. cerris seedlings, planted in containers around the nurse plant. After 6 months, colonized nursling plant root tips showed that mycorrhiza formation by T. melanosporum was higher than 45 % in the seedlings tested, with the most successful nursling combination being Q. cerris seedlings, reaching 81 % colonization. Bulk identification of T. melanosporum mycorrhizae was based on morphological and anatomical features and confirmed by sequencing of the internal transcribed spacer region of the ribosomal DNA of selected root tips. Our results show that the nurse plant method yields attractive rates of mycorrhiza formation by the Périgord black truffle and suggest that establishing and maintaining common mycorrhizal networks in pot cultures enables sustained use of the initial spore inoculum.
Report of Official Foreign Travel to Montreal, Canada
DOE Office of Scientific and Technical Information (OSTI.GOV)
Mason, J. D.
How can DOE, NNSA, and Y-12 best handle the integration of information from diverse sources, and what will best ensure that legacy data will survive changes in computing systems for the future? Although there is no simple answer, it is becoming increasingly clear throughout the information-management industry that a key component of both preservation and integration of information is the adoption of standardized data formats. The most notable standardized format is XML, to which almost all data is now migrating. XML is derived from SGML, as is HTML, the common language of the World Wide Web. XML is becoming increasinglymore » important as part of the Y-12 data infrastructure. Y-12 is implementing a new generation of XML-based publishing systems. Y-12 already has been supporting projects at DOE Headquarters, such as the Guidance Streamlining Initiative (GSI) that will result in the storage of classification guidance in XML. Y-12 collects some test data in XML as the result of Electronic Data Capture (EDC), and XML data is also used in Engineering Releases. I am participating in a series of projects sponsored by the PRIDE initiative that include the capture of dimensional certification and other similar records in XML, the creation of XML formats for Electronic Data Capture, and the creation of Quality Evaluation Reports in XML. In support of DOE's use of SGML, XML, HTML, Topic Maps, and related standards, I served 1985-2007 as chairman of the international committee responsible for SGML and standards derived from it, ISO/IEC JTC1/SC34 (SC34) and its predecessor organizations; I continue to belong to the committee. During the August 2010 trip, I co-chaired the conference Balisage 2010.« less
Transferable Output ASCII Data (TOAD) gateway: Version 1.0 user's guide
NASA Technical Reports Server (NTRS)
Bingel, Bradford D.
1991-01-01
The Transferable Output ASCII Data (TOAD) Gateway, release 1.0 is described. This is a software tool for converting tabular data from one format into another via the TOAD format. This initial release of the Gateway allows free data interchange among the following file formats: TOAD; Standard Interface File (SIF); Program to Optimize Simulated Trajectories (POST) input; Comma Separated Value (TSV); and a general free-form file format. As required, additional formats can be accommodated quickly and easily.
Enhancing the incorporation of the patient's voice in drug development and evaluation.
Chalasani, Meghana; Vaidya, Pujita; Mullin, Theresa
2018-01-01
People living with a condition are uniquely positioned to inform the understanding of the therapeutic context for drug development and evaluation. In 2012, the U.S. Food and Drug Administration (FDA) established the Patient-Focused Drug Development (PFDD) initiative to more systematically obtain the patient perspective on specific diseases and their currently available treatments. PFDD meetings are unique among FDA public meetings, with a format designed to engage patients and elicit their perspectives on two topic areas: (1) the most significant symptoms of their condition and the impact of the condition on daily life; and, (2) their current approaches to treatment. FDA has conducted 24 disease-specific PFDD meetings to date. The lessons learned from PFDD meetings range from experiences common across rare diseases to more disease specific experiences that matter most to patients. FDA recognizes that FDA-led PFDD meetings alone cannot address the gaps in information on the patient perspective. Patient-focused drug development is an ongoing effort and FDA looks forward to the next steps in advancing the science and the utilization of patient input throughout drug development and evaluation. The U.S. Food and Drug Administration (FDA) has multiple mechanisms for its regulators and staff to interact with patients -- but none quite like its novel Patient-Focused Drug Development (PFDD) initiative. FDA established the PFDD initiative to more systematically obtain the patient perspective on specific diseases and their currently available treatments. Since the initiative's inception in 2012, FDA has held 24 PFDD meetings, covering a range of disease areas and hearing directly from thousands of patients and caregivers. FDA's PFDD meetings have also provided key stakeholders, including patient advocates, researchers, drug developers, healthcare providers, and other government officials, an opportunity to hear the patient's voice. The lessons learned include but are not limited to specific experiences that matter most to patients, patient perspectives on meaningful treatment benefits and how patients want to be engaged in the drug development process. FDA recognizes that FDA-led PFDD meetings alone cannot address the gaps in information on the patient perspective. Further enhancing the incorporation of the patient's voice in drug development and evaluation continues to be a priority for FDA.
Galmarini, Stefano; Koffi, Brigitte; Solazzo, Efisio; Keating, Terry; Hogrefe, Christian; Schulz, Michael; Benedictow, Anna; Griesfeller, Jan Jurgen; Janssens-Maenhout, Greet; Carmichael, Greg; Fu, Joshua; Dentener, Frank
2017-01-31
We present an overview of the coordinated global numerical modelling experiments performed during 2012-2016 by the Task Force on Hemispheric Transport of Air Pollution (TF HTAP), the regional experiments by the Air Quality Model Evaluation International Initiative (AQMEII) over Europe and North America, and the Model Intercomparison Study for Asia (MICS-Asia). To improve model estimates of the impacts of intercontinental transport of air pollution on climate, ecosystems, and human health and to answer a set of policy-relevant questions, these three initiatives performed emission perturbation modelling experiments consistent across the global, hemispheric, and continental/regional scales. In all three initiatives, model results are extensively compared against monitoring data for a range of variables (meteorological, trace gas concentrations, and aerosol mass and composition) from different measurement platforms (ground measurements, vertical profiles, airborne measurements) collected from a number of sources. Approximately 10 to 25 modelling groups have contributed to each initiative, and model results have been managed centrally through three data hubs maintained by each initiative. Given the organizational complexity of bringing together these three initiatives to address a common set of policy-relevant questions, this publication provides the motivation for the modelling activity, the rationale for specific choices made in the model experiments, and an overview of the organizational structures for both the modelling and the measurements used and analysed in a number of modelling studies in this special issue.
NASA Astrophysics Data System (ADS)
Galmarini, Stefano; Koffi, Brigitte; Solazzo, Efisio; Keating, Terry; Hogrefe, Christian; Schulz, Michael; Benedictow, Anna; Griesfeller, Jan Jurgen; Janssens-Maenhout, Greet; Carmichael, Greg; Fu, Joshua; Dentener, Frank
2017-01-01
We present an overview of the coordinated global numerical modelling experiments performed during 2012-2016 by the Task Force on Hemispheric Transport of Air Pollution (TF HTAP), the regional experiments by the Air Quality Model Evaluation International Initiative (AQMEII) over Europe and North America, and the Model Intercomparison Study for Asia (MICS-Asia). To improve model estimates of the impacts of intercontinental transport of air pollution on climate, ecosystems, and human health and to answer a set of policy-relevant questions, these three initiatives performed emission perturbation modelling experiments consistent across the global, hemispheric, and continental/regional scales. In all three initiatives, model results are extensively compared against monitoring data for a range of variables (meteorological, trace gas concentrations, and aerosol mass and composition) from different measurement platforms (ground measurements, vertical profiles, airborne measurements) collected from a number of sources. Approximately 10 to 25 modelling groups have contributed to each initiative, and model results have been managed centrally through three data hubs maintained by each initiative. Given the organizational complexity of bringing together these three initiatives to address a common set of policy-relevant questions, this publication provides the motivation for the modelling activity, the rationale for specific choices made in the model experiments, and an overview of the organizational structures for both the modelling and the measurements used and analysed in a number of modelling studies in this special issue.
Galmarini, Stefano; Koffi, Brigitte; Solazzo, Efisio; Keating, Terry; Hogrefe, Christian; Schulz, Michael; Benedictow, Anna; Griesfeller, Jan Jurgen; Janssens-Maenhout, Greet; Carmichael, Greg; Fu, Joshua; Dentener, Frank
2018-01-01
We present an overview of the coordinated global numerical modelling experiments performed during 2012–2016 by the Task Force on Hemispheric Transport of Air Pollution (TF HTAP), the regional experiments by the Air Quality Model Evaluation International Initiative (AQMEII) over Europe and North America, and the Model Intercomparison Study for Asia (MICS-Asia). To improve model estimates of the impacts of intercontinental transport of air pollution on climate, ecosystems, and human health and to answer a set of policy-relevant questions, these three initiatives performed emission perturbation modelling experiments consistent across the global, hemispheric, and continental/regional scales. In all three initiatives, model results are extensively compared against monitoring data for a range of variables (meteorological, trace gas concentrations, and aerosol mass and composition) from different measurement platforms (ground measurements, vertical profiles, airborne measurements) collected from a number of sources. Approximately 10 to 25 modelling groups have contributed to each initiative, and model results have been managed centrally through three data hubs maintained by each initiative. Given the organizational complexity of bringing together these three initiatives to address a common set of policy-relevant questions, this publication provides the motivation for the modelling activity, the rationale for specific choices made in the model experiments, and an overview of the organizational structures for both the modelling and the measurements used and analysed in a number of modelling studies in this special issue. PMID:29541091
NASA Astrophysics Data System (ADS)
Pan, A. F.; Wang, W. J.; Mei, X. S.; Yang, H. Z.; Sun, X. F.
2017-01-01
We report the formation and evolution mechanisms of HSFLs (high-spatial-frequency laser-induced periodic surface structures) on the commercial pure titanium under 10-ps 532-nm-wavelength laser irradiation. At a lower peak laser fluence, HSFLs in the rough zone are first formed along the surface texture. Subsequently, HSFLs in the flat zone are formed with an orientation parallel to the laser polarization direction. The formation of HSFLs can be attributed to the parallel orientation of the initial periodic modulation of the electron plasma concentration to the laser polarization direction. In particular, the formation of HSFLs along the surface texture occurs because the absorbed laser energy density is along the surface texture. At a higher peak laser fluence, two types of HSFLs appear together with LSFLs. The first type involves HSFLs that initially cover the concave part of the LSFL (low-spatial-frequency laser-induced periodic surface structures) and penetrate inward as the number of spot overlaps increases. This formation mechanism can be attributed to cavitation instability. The second type involves HSFLs that are initially in the convex part of the LSFL, and they are transformed into oxidized nanodots as the number of spot overlaps increases. The oxidized nanodots increase the absorption of laser energy in titanium, which leads to the ablation and removal of the oxidized material. Therefore, the surface of the LSFL becomes smooth.
Deswelling kinetics of polyacrylate gels in solutions of cetyltrimethylammonium bromide.
Nilsson, Peter; Hansson, Per
2007-08-23
The deswelling kinetics of single sodium polyacrylate gel beads (radius 40-160 microm) in aqueous solutions of cetyltrimethylammonium bromide under conditions of forced convection are investigated using micromanipulator assisted light microscopy. The purpose of the study is to further evaluate a previously published model (J. Phys. Chem. B 2003, 107, 9203) using a higher homolog surfactant. For gels with expected fast deswelling (small gel size/low surfactant concentration) and/or in low electrolyte concentration, the model is found to correctly predict the deswelling characteristics of the gel beads. However, for some gels with expected slow deswelling, especially in high electrolyte concentration (10 mM NaBr), the model widely underestimates the required deswelling time. The reason for this is argued to be the longer time frame and high bromide concentration allowing the formation of a denser, more ordered structure in the surface phase, which resists the deformation and reorganization of material necessary for deswelling. Unexpectedly long lag times before the start of deswelling are also found for gels in low surfactant concentration, indicating that a relatively high surfactant concentration in the gel, greatly exceeding the critical aggregation concentration, is needed to start formation of a collapsed surface phase. This critical surfactant concentration is found to be dependent on initial gel radius, as small gels require a relatively higher concentration to initiate collapse.
Randall, Rachel M; Shao, Yvonne Y; Wang, Lai; Ballock, R Tracy
2012-12-01
Disrupting the Wnt Planar Cell Polarity (PCP) signaling pathway in vivo results in loss of columnar growth plate architecture, but it is unknown whether activation of this pathway in vitro is sufficient to promote column formation. We hypothesized that activation of the Wnt PCP pathway in growth plate chondrocyte cell pellets would promote columnar organization in these cells that are normally oriented randomly in culture. Rat growth plate chondrocytes were transfected with plasmids encoding the Fzd7 cell-surface Wnt receptor, a Fzd7 deletion mutant lacking the Wnt-binding domain, or Wnt receptor-associated proteins Ror2 or Vangl2, and then cultured as three-dimensional cell pellets in the presence of recombinant Wnt5a or Wnt5b for 21 days. Cellular morphology was evaluated using histomorphometric measurements. Activation of Wnt PCP signaling components promoted the initiation of columnar morphogenesis in the chondrocyte pellet culture model, as measured by histomorphometric analysis of the column index (ANOVA p = 0.01). Activation of noncanonical Wnt signaling through overexpression of both the cell-surface Wnt receptor Fzd7 and receptor-associated protein Ror2 with addition of recombinant Wnt5a promotes the initiation of columnar architecture of growth plate chondrocytes in vitro, representing an important step toward growth plate regeneration. Copyright © 2012 Orthopaedic Research Society.
Teng, Ellen J; Barrera, Terri L; Hiatt, Emily L; Chaison, Angelic D; Dunn, Nancy Jo; Petersen, Nancy J; Stanley, Melinda A
2015-06-01
This pilot study examines the feasibility, acceptability, and potential effectiveness of delivering an intensive weekend group treatment for panic disorder (PD) to Veterans returning from deployments to Iraq and Afghanistan with co-occurring posttraumatic stress disorder (PTSD). The treatment program lasted 6h each day and was delivered by two experienced therapists. Patients received core components of panic treatment, including psychoeducation, cognitive restructuring, and interoceptive exposure. The interoceptive exposure exercises directly targeted anxiety sensitivity, a psychological construct also implicated in the maintenance of PTSD. Eighty-nine percent of patients who expressed interest in the treatment attended a baseline evaluation, and 63% of those who were study eligible initiated treatment. Treatment retention was high, with all 10 patients who initiated treatment completing the program. Veterans reported finding the treatment and delivery format highly acceptable and reported high levels of satisfaction. Panic symptoms improved significantly following the treatment and were maintained at a 7-month follow-up, with 71.4% of the sample reporting being panic free. Co-occurring PTSD symptoms also improved along with symptoms of anxiety and depression. Preliminary findings suggest that brief and intensive group treatments for PD/PTSD are a promising method of delivering cognitive behavioral therapy that may rapidly improve symptoms. This innovative treatment delivery format also may be a cost-effective way of increasing treatment engagement through increased access to quality care. Published by Elsevier Ltd.
Professional Development through Formative Evaluation
ERIC Educational Resources Information Center
Nsibande, Rejoice; Garraway, James
2011-01-01
Formative evaluation and its associated methodology of reflection on practice are used extensively in academic staff development. In reflecting on formative evaluation processes in both more traditional and newer programmes conducted at a university of technology, a number of variables reported in the literature were observed to have influenced…
Hammond, Karl D.; Wirth, Brian D.
2014-10-09
Here, we present atomistic simulations that show the effect of surface orientation on helium depth distributions and surface feature formation as a result of low-energy helium plasma exposure. We find a pronounced effect of surface orientation on the initial depth of implanted helium ions, as well as a difference in reflection and helium retention across different surface orientations. Our results indicate that single helium interstitials are sufficient to induce the formation of adatom/substitutional helium pairs under certain highly corrugated tungsten surfaces, such as {1 1 1}-orientations, leading to the formation of a relatively concentrated layer of immobile helium immediately belowmore » the surface. The energies involved for helium-induced adatom formation on {1 1 1} and {2 1 1} surfaces are exoergic for even a single adatom very close to the surface, while {0 0 1} and {0 1 1} surfaces require two or even three helium atoms in a cluster before a substitutional helium cluster and adatom will form with reasonable probability. This phenomenon results in much higher initial helium retention during helium plasma exposure to {1 1 1} and {2 1 1} tungsten surfaces than is observed for {0 0 1} or {0 1 1} surfaces and is much higher than can be attributed to differences in the initial depth distributions alone. Lastly, the layer thus formed may serve as nucleation sites for further bubble formation and growth or as a source of material embrittlement or fatigue, which may have implications for the formation of tungsten “fuzz” in plasma-facing divertors for magnetic-confinement nuclear fusion reactors and/or the lifetime of such divertors.« less
NASA Technical Reports Server (NTRS)
Peretyazhko, T. A.; Rampe, E. B.; Clark, J. V.; Archer, P. D., Jr.; Morris, R. V.; Ming, D. V.
2017-01-01
Akaganeite (Beta-FeOOH, chloride-containing Fe(III) (hydr)oxide) has been recently discovered on the surface of Mars by the Mars Science Laboratory Curiosity rover in Yellowknife Bay, Gale Crater, Mars [1] and from orbit by the Mars Reconnaissance Orbiter in Robert Sharp crater and Antoniadi basin [2]. However, the mechanism and aqueous environmental conditions of akaganeite formation (e.g., pH and chloride concentration) remain unknown. We have investigated formation of akaganeite through Fe(III) hydrolysis at variable initial pH and chloride concentrations. The formed Fe(III) precipitates were characterized by instruments similar to instruments on Mars robotic spacecraft. Syntheses were performed through hydrolysis of Fe(III) perchlorate with addition of Na cloride (Fe/Cl ratio between 0.5 and 5) and at initial pH of 1.5, 2, 4, 6 and 8 at 90degC. X-ray diffraction analysis revealed formation of akaganeite alone or in mixture with goethite, hematite and ferrihydrite at all initial pHs and Fe/Cl ratio between 0.5 and 2 while akaganeite precipitated only at pH 1.5 and Fe/Cl greater than2. Chloride content of akaganeite was affected by initial pH and decreased from 20-60 mg/g at pH 1.5 to less than 0.1 mg/g at pH 8. The synthesized akaganeite samples were also characterized by Mössbauer and infrared spectroscopy and volatiles were analysed by thermal and evolved gas analysis. The obtained characterization data will be compared to published data from rover and orbital missions [1-3] to determine martian akaganeite composition, crystallinity and formation conditions.
Zhang, Qi; Anastasio, Cort
2003-08-15
Although organic nitrogen (ON) compounds are apparently ubiquitous in the troposphere, very little is known about their fate and transformations. As one step in addressing this issue, we have studied the transformations of bulk (uncharacterized) organic nitrogen in fogwaters and aerosol aqueous extracts during exposure to simulated sunlight and O3. Our results show that over the course of several hours of exposure a significant portion of condensed-phase organic nitrogen is transformed into ammonium, nitrite, nitrate, and NOx. For nitrite, there was both photochemical formation and destruction, resulting in a slow net loss. Ammonium and nitrate were formed at initial rates on the order of a few micromolar per hour in the bulk fogwaters, corresponding to formation rates of approximately 10 and 40 ng m(-3) h(-1), respectively, in ambient fog. The average initial formation rate (expressed as ng (m of air)(-3) h(-1)) of NH4+ in the aqueous extracts of fine particles (PM2.5) was approximately one-half of the corresponding fogwater value. Initial formation rates of NOx (i.e., NO + NO2) were equivalent to approximately 2-11 pptv h(-1) in the three fogwaters tested. Although the formation rates of ammonium and nitrate were relatively small as compared to their initial concentrations in fogwaters (approximately 200-2000 microM) and aerosol particles (approximately 400-1500 ng m(-3)), this photochemical mineralization and "renoxification" from condensed-phase organic N is a previously uncharacterized source of inorganic N in the atmosphere. This conversion also represents a new component in the biogeochemical cycle of nitrogen that might have significant influences on atmospheric composition, condensed-phase properties, and the ecological impacts of N deposition.
Kirby, S.M.; Janecke, S.U.; Dorsey, R.J.; Housen, B.A.; Langenheim, V.E.; McDougall, K.A.; Steeley, A.N.
2007-01-01
We examine the Pleistocene tectonic reorganization of the Pacific-North American plate boundary in the Salton Trough of southern California with an integrated approach that includes basin analysis, magnetostratigraphy, and geologic mapping of upper Pliocene to Pleistocene sedimentary rocks in the San Felipe Hills. These deposits preserve the earliest sedimentary record of movement on the San Felipe and San Jacinto fault zones that replaced and deactivated the late Cenozoic West Salton detachment fault. Sandstone and mudstone of the Brawley Formation accumulated between ???1.1 and ???0.6-0.5 Ma in a delta on the margin of an arid Pleistocene lake, which received sediment from alluvial fans of the Ocotillo Formation to the west-southwest. Our analysis indicates that the Ocotillo and Brawley formations prograded abruptly to the east-northeast across a former mud-dominated perennial lake (Borrego Formation) at ???1.1 Ma in response to initiation of the dextral-oblique San Felipe fault zone. The ???25-km-long San Felipe anticline initiated at about the same time and produced an intrabasinal basement-cored high within the San Felipe-Borrego basin that is recorded by progressive unconformities on its north and south limbs. A disconformity at the base of the Brawley Formation in the eastern San Felipe Hills probably records initiation and early blind slip at the southeast tip of the Clark strand of the San Jacinto fault zone. Our data are consistent with abrupt and nearly synchronous inception of the San Jacinto and San Felipe fault zones southwest of the southern San Andreas fault in the early Pleistocene during a pronounced southwestward broadening of the San Andreas fault zone. The current contractional geometry of the San Jacinto fault zone developed after ???0.5-0.6 Ma during a second, less significant change in structural style. ?? 2007 by The University of Chicago. All rights reserved.
Kahvejian, Avak; Svitkin, Yuri V; Sukarieh, Rami; M'Boutchou, Marie-Noël; Sonenberg, Nahum
2005-01-01
Translation initiation is a multistep process involving several canonical translation factors, which assemble at the 5'-end of the mRNA to promote the recruitment of the ribosome. Although the 3' poly(A) tail of eukaryotic mRNAs and its major bound protein, the poly(A)-binding protein (PABP), have been studied extensively, their mechanism of action in translation is not well understood and is confounded by differences between in vivo and in vitro systems. Here, we provide direct evidence for the involvement of PABP in key steps of the translation initiation pathway. Using a new technique to deplete PABP from mammalian cell extracts, we show that extracts lacking PABP exhibit dramatically reduced rates of translation, reduced efficiency of 48S and 80S ribosome initiation complex formation, and impaired interaction of eIF4E with the mRNA cap structure. Supplementing PABP-depleted extracts with wild-type PABP completely rectified these deficiencies, whereas a mutant of PABP, M161A, which is incapable of interacting with eIF4G, failed to restore translation. In addition, a stronger inhibition (approximately twofold) of 80S as compared to 48S ribosome complex formation (approximately 65% vs. approximately 35%, respectively) by PABP depletion suggests that PABP plays a direct role in 60S subunit joining. PABP can thus be considered a canonical translation initiation factor, integral to initiation complex formation at the 5'-end of mRNA.
Kahvejian, Avak; Svitkin, Yuri V.; Sukarieh, Rami; M'Boutchou, Marie-Noël; Sonenberg, Nahum
2005-01-01
Translation initiation is a multistep process involving several canonical translation factors, which assemble at the 5′-end of the mRNA to promote the recruitment of the ribosome. Although the 3′ poly(A) tail of eukaryotic mRNAs and its major bound protein, the poly(A)-binding protein (PABP), have been studied extensively, their mechanism of action in translation is not well understood and is confounded by differences between in vivo and in vitro systems. Here, we provide direct evidence for the involvement of PABP in key steps of the translation initiation pathway. Using a new technique to deplete PABP from mammalian cell extracts, we show that extracts lacking PABP exhibit dramatically reduced rates of translation, reduced efficiency of 48S and 80S ribosome initiation complex formation, and impaired interaction of eIF4E with the mRNA cap structure. Supplementing PABP-depleted extracts with wild-type PABP completely rectified these deficiencies, whereas a mutant of PABP, M161A, which is incapable of interacting with eIF4G, failed to restore translation. In addition, a stronger inhibition (approximately twofold) of 80S as compared to 48S ribosome complex formation (∼65% vs. ∼35%, respectively) by PABP depletion suggests that PABP plays a direct role in 60S subunit joining. PABP can thus be considered a canonical translation initiation factor, integral to initiation complex formation at the 5′-end of mRNA. PMID:15630022
A Multi-Faceted Formative Assessment Approach: Better Recognising the Learning Needs of Students
ERIC Educational Resources Information Center
Jenkins, James O.
2010-01-01
Students are increasingly subject to a series of learning pressures that prevent effective engagement in assessment. Thus, the aim of this study was to create a multi-faceted formative assessment approach that better enabled students to engage in the assessment process. A formative assessment approach, consisting of six key initiatives, is…
NASA Technical Reports Server (NTRS)
Borisenko, V. I.; Chesalin, L. S.
1980-01-01
The algorithm, block diagram, complete text, and instructions are given for the use of a computer program to separate formations whose spectral characteristics are constant on the average. The initial material for operating the computer program presented is video information in a standard color-superposition format.
NASA Astrophysics Data System (ADS)
McCartney, Tannis Maureen
Tectonic subsidence curves for over 300 subsurface wells in west-central Alberta indicate that the Western Canada Foreland Basin was initiated at the same time the lower units of the Fernie Formation were being deposited. This evidence is further supported by sedimentological data and fits with the timing of the onset of deformation in the Cordillera and the initiation of the foreland basin in Montana. The volume of subsidence curves in this study required an innovative methodology. Subsidence calculations were performed using customized macros in a spreadsheet. The tectonic subsidence variations were displayed in a tectonic subsidence envelope, which showed the total variation in the subsidence curves, and three suites of maps: tectonic subsidence, tectonic subsidence residuals, and tectonic subsidence ratios. Collectively, the maps of the tectonic subsidence in the Fernie Formation show that there was a western influence on subsidence during deposition of the oldest members of the Fernie Formation.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Zhai, Ziqing; Toloczko, Mychailo B.; Kruska, Karen
Long-term grain boundary (GB) damage evolution and stress corrosion crack initiation in alloy 690 are being investigated by constant load tensile testing in high-temperature, simulated PWR primary water. Six commercial alloy 690 heats are being tested in various cold work conditions loaded at their yield stress. This paper reviews the basic test approach and detailed characterizations performed on selected specimens after an exposure time of ~1 year. Intergranular crack nucleation was observed under constant stress in certain highly cold-worked (CW) alloy 690 heats and was found to be associated with the formation of GB cavities. Somewhat surprisingly, the heats mostmore » susceptible to cavity formation and crack nucleation were thermally treated materials with most uniform coverage of small GB carbides. Microstructure, % cold work and applied stress comparisons are made among the alloy 690 heats to better understand the factors influencing GB cavity formation and crack initiation.« less
Neutrophil Extracellular Trap-Related Extracellular Histones Cause Vascular Necrosis in Severe GN.
Kumar, Santhosh V R; Kulkarni, Onkar P; Mulay, Shrikant R; Darisipudi, Murthy N; Romoli, Simone; Thomasova, Dana; Scherbaum, Christina R; Hohenstein, Bernd; Hugo, Christian; Müller, Susanna; Liapis, Helen; Anders, Hans-Joachim
2015-10-01
Severe GN involves local neutrophil extracellular trap (NET) formation. We hypothesized a local cytotoxic effect of NET-related histone release in necrotizing GN. In vitro, histones from calf thymus or histones released by neutrophils undergoing NETosis killed glomerular endothelial cells, podocytes, and parietal epithelial cells in a dose-dependent manner. Histone-neutralizing agents such as antihistone IgG, activated protein C, or heparin prevented this effect. Histone toxicity on glomeruli ex vivo was Toll-like receptor 2/4 dependent, and lack of TLR2/4 attenuated histone-induced renal thrombotic microangiopathy and glomerular necrosis in mice. Anti-glomerular basement membrane GN involved NET formation and vascular necrosis, whereas blocking NET formation by peptidylarginine inhibition or preemptive anti-histone IgG injection significantly reduced all aspects of GN (i.e., vascular necrosis, podocyte loss, albuminuria, cytokine induction, recruitment or activation of glomerular leukocytes, and glomerular crescent formation). To evaluate histones as a therapeutic target, mice with established GN were treated with three different histone-neutralizing agents. Anti-histone IgG, recombinant activated protein C, and heparin were equally effective in abrogating severe GN, whereas combination therapy had no additive effects. Together, these results indicate that NET-related histone release during GN elicits cytotoxic and immunostimulatory effects. Furthermore, neutralizing extracellular histones is still therapeutic when initiated in established GN. Copyright © 2015 by the American Society of Nephrology.
Enzyme activity and AGE formation in a model of AST glycoxidation by D-fructose in vitro.
Bousova, Iva; Vukasović, Danka; Juretić, Dubravka; Palicka, Vladimir; Drsata, Jaroslav
2005-03-01
Non-enzymatic glycation as the chain reaction between reducing sugars and free amino groups of proteins has been shown to correlate with physiological ageing and severity of diabetes. The process involves oxidative steps (glycoxidation). In this paper, the effect of D-fructose as a reactive sugar on aspartate aminotransferase (AST) as a model protein was monitored by measurements of the enzyme activity and formation of fluorescent advanced glycation end products (AGEs). Change in the AST activity was considered as a measure of the overall protein damage caused by glycation, and total AGEs and pentosidine represent, at least partly, the formation of glycoxidation products. Catalytic activity of AST in an incubation mixture containing D-fructose (50 mmol L(-1)), decreased compared to control values to 42% (p < 0.05) and to 11% (p < 0.05) on the 5th and on 21st day of incubation, respectively. In the presence of fructose, total fluorescent AGEs concentration was significantly higher since 5th day of incubation (110%, p < 0.05) and the fluorescent pentosidine concentration from 15th day of incubation (117%, p < 0.05) compared to control values, respectively. Catalytic activity of AST clearly and quantitatively demonstrated functional changes in the enzyme molecule caused by structural modifications initiated by fructose, while the evaluation of AGE formation and especially that of pentosidine by fluorescence measurement was less reliable.
Inhibition of quorum-sensing-mediated biofilm formation in Cronobacter sakazakii strains.
Singh, Niharika; Patil, Amrita; Prabhune, Asmita; Goel, Gunjan
2016-09-01
The present study investigated plant extracts for their anti-quorum-sensing (QS) potential to inhibit the biofilm formation in Cronobacter sakazakii strains. The bioassay based on loss of pigment production by Chromobacterium violaceum 026 and Agrobacterium tumefaciens NTL4(pZLR4) was used for initial screening of the extracts. Further, the effect of extracts on the inhibition of QS-mediated biofilm in C. sakazakii isolates was evaluated using standard crystal violet assay. The effect on biofilm texture was studied using SYTO9 staining and light and scanning electron microscopy. Among the tested extracts, Piper nigrum and Cinnamomum verum at 100 ppm resulted in 78 and 68 % reduction in the production of violacein as well as blue-green colour in both biosensor strains. A higher inhibitory activity (>50 %) on biofilm formation in C. sakazakii was observed for Pip. nigrum and Cin. verum, whereas the other extracts possessed moderate (25-50 %) and minimal (<25 %) inhibitory activities. Further, the fluorescent and scanning electron microscopic images indicated a major disruption in the architecture of biofilms of tested strains by Pip. nigrum. This study points to the possibility of using Pip. nigrum and Cin. verum as inhibitor of QS-mediated biofilm formation by C. sakazakii that could be further explored for novel bioactive molecules to limit the emerging infections of C. sakazakii.
Fernández, Tulio; Olave, Gilberto; Valencia, Carlos H; Arce, Sandra; Quinn, Julian M W; Thouas, George A; Chen, Qi-Zhi
2014-07-01
Vascularization of an artificial graft represents one of the most significant challenges facing the field of bone tissue engineering. Over the past decade, strategies to vascularize artificial scaffolds have been intensively evaluated using osteoinductive calcium phosphate (CaP) biomaterials in animal models. In this work, we observed that CaP-based biomaterials implanted into rat calvarial defects showed remarkably accelerated formation and mineralization of new woven bone in defects in the initial stages, at a rate of ∼60 μm/day (0.8 mg/day), which was considerably higher than normal bone growth rates (several μm/day, 0.1 mg/day) in implant-free controls of the same age. Surprisingly, we also observed histological evidence of primary osteon formation, indicated by blood vessels in early-region fibrous tissue, which was encapsulated by lamellar osteocyte structures. These were later fully replaced by compact bone, indicating complete regeneration of calvarial bone. Thus, the CaP biomaterial used here is not only osteoinductive, but vasculogenic, and it may have contributed to the bone regeneration, despite an absence of osteons in normal rat calvaria. Further investigation will involve how this strategy can regulate formation of vascularized cortical bone such as by control of degradation rate, and use of models of long, dense bones, to more closely approximate repair of human cortical bone.
Customizable PCR-microplate array for differential identification of multiple pathogens
Woubit, Abdela; Yehualaeshet, Teshome; Roberts, Sherrelle; Graham, Martha; Kim, Moonil; Samuel, Temesgen
2014-01-01
Customizable PCR-microplate arrays were developed for the rapid identification of Francisella tularensis subsp. tularensis, Salmonella Typhi, Shigella dysenteriae, Yersinia pestis, Vibrio cholerae Escherichia coli O157:H7, Salmonella Typhimurium, Salmonella Saintpaul, Francisella tularensis subsp. novicida, Vibrio parahaemolyticus, and Yersinia pseudotuberculosis. Previously, we identified highly specific primers targeting each of the pathogens above. Here, we report the development of customizable PCR-microplate arrays for simultaneous identification of the pathogens using the primers. A mixed aliquot of genomic DNA from 38 different strains was used to validate three PCR-microplate array formats. Identical PCR conditions were used to run all the samples on the three formats. Results show specific amplifications on all the three custom plates. In a preliminary test to evaluate the sensitivity of these assays in laboratory-inoculated samples, detection limits as low as 9 cfu/g/ml S. Typhimurium were obtained from beef hot dog, and 78 cfu/ml from milk. Such microplate arrays could serve as valuable tools for initial identification or secondary confirmation of these pathogens. PMID:24215700
DeBonis, Katrina; Blair, Thomas R; Payne, Samuel T; Wigan, Katherine; Kim, Sara
2015-12-01
Web-based instruction in post-graduate psychiatry training has shown comparable effectiveness to in-person instruction, but few topics have been addressed in this format. This study sought to evaluate the viability of a web-based curriculum in teaching electrocardiogram (EKG) reading skills to psychiatry residents. Interest in receiving educational materials in this format was also assessed. A web-based curriculum of 41 slides, including eight pre-test and eight post-test questions with emphasis on cardiac complications of psychotropic medications, was made available to all psychiatry residents via email. Out of 57 residents, 30 initiated and 22 completed the module. Mean improvement from pre-test to post-test was 25 %, and all 22 completing participants indicated interest in future web-based instruction. This pilot study suggests that web-based instruction is feasible and under-utilized as a means of teaching psychiatry residents. Potential uses of web-based instruction, such as tracking learning outcomes or patient care longitudinally, are also discussed.
NASA Technical Reports Server (NTRS)
Drachman, Richard J.
2006-01-01
Formation of triplet positron-helium bound state by stripping of positronium atoms in collision with ground state helium JOSEPH DI RlENZI, College of Notre Dame of Maryland, RICHARD J. DRACHMAN, NASA/Goddard Space Flight Center - The system consisting of a positron and a helium atom in the triplet state e(+)He(S-3)(sup e) was conjectured long ago to be stable [1]. Its stability has recently been established rigorously [2], and the values of the energies of dissociation into the ground states of Ps and He(+) have also been reported [3] and [4]. We have evaluated the cross-section for this system formed by radiative attachment of a positron in triplet He state and found it to be small [5]. The mechanism of production suggested here should result in a larger cross-section (of atomic size) which we are determining using the Born approximation with simplified initial and final wave functions.
The origin of multiple clones in the parthenogenetic lizard species Darevskia rostombekowi.
Ryskov, Alexey P; Osipov, Fedor A; Omelchenko, Andrey V; Semyenova, Seraphima K; Girnyk, Anastasiya E; Korchagin, Vitaly I; Vergun, Andrey A; Murphy, Robert W
2017-01-01
The all-female Caucasian rock lizard Darevskia rostombekowi and other unisexual species of this genus reproduce normally via true parthenogenesis. Typically, diploid parthenogenetic reptiles exhibit some amount of clonal diversity. However, allozyme data from D. rostombekowi have suggested that this species consists of a single clone. Herein, we test this hypothesis by evaluating variation at three variable microsatellite loci for 42 specimens of D. rostombekowi from four populations in Armenia. Analyses based on single nucleotide polymorphisms of each locus reveal five genotypes or presumptive clones in this species. All individuals are heterozygous at the loci. The major clone occurs in 24 individuals and involves three populations. Four rare clones involve one or several individuals from one or two populations. Most variation owes to parent-specific single nucleotide polymorphisms, which occur as heterozygotes. This result fails to reject the hypothesis of a single hybridization founder event that resulted in the initial formation of one major clone. The other clones appear to have originated via post-formation microsatellite mutations of the major clone.
The development of computer networks: First results from a microeconomic model
NASA Astrophysics Data System (ADS)
Maier, Gunther; Kaufmann, Alexander
Computer networks like the Internet are gaining importance in social and economic life. The accelerating pace of the adoption of network technologies for business purposes is a rather recent phenomenon. Many applications are still in the early, sometimes even experimental, phase. Nevertheless, it seems to be certain that networks will change the socioeconomic structures we know today. This is the background for our special interest in the development of networks, in the role of spatial factors influencing the formation of networks, and consequences of networks on spatial structures, and in the role of externalities. This paper discusses a simple economic model - based on a microeconomic calculus - that incorporates the main factors that generate the growth of computer networks. The paper provides analytic results about the generation of computer networks. The paper discusses (1) under what conditions economic factors will initiate the process of network formation, (2) the relationship between individual and social evaluation, and (3) the efficiency of a network that is generated based on economic mechanisms.
NASA Technical Reports Server (NTRS)
Canuto, V. M.
1978-01-01
A review of big-bang cosmology is presented, emphasizing the big-bang model, hypotheses on the origin of galaxies, observational tests of the big-bang model that may be possible with the Large Space Telescope, and the scale-covariant theory of gravitation. Detailed attention is given to the equations of general relativity, the redshift-distance relation for extragalactic objects, expansion of the universe, the initial singularity, the discovery of the 3-K blackbody radiation, and measurements of the amount of deuterium in the universe. The curvature of the expanding universe is examined along with the magnitude-redshift relation for quasars and galaxies. Several models for the origin of galaxies are evaluated, and it is suggested that a model of galaxy formation via the formation of black holes is consistent with the model of an expanding universe. Scale covariance is discussed, a scale-covariant theory is developed which contains invariance under scale transformation, and it is shown that Dirac's (1937) large-numbers hypothesis finds a natural role in this theory by relating the atomic and Einstein units.
Eyre, Rachel; Alférez, Denis G; Spence, Kath; Kamal, Mohamed; Shaw, Frances L; Simões, Bruno M; Santiago-Gómez, Angélica; Sarmiento-Castro, Aida; Bramley, Maria; Absar, Mohammed; Saad, Zahida; Chatterjee, Sumohan; Kirwan, Cliona; Gandhi, Ashu; Armstrong, Anne C; Wardley, Andrew M; O'Brien, Ciara S; Farnie, Gillian; Howell, Sacha J; Clarke, Robert B
2016-12-01
Breast cancer specific mortality results from tumour cell dissemination and metastatic colonisation. Identification of the cells and processes responsible for metastasis will enable better prevention and control of metastatic disease, thus reducing relapse and mortality. To better understand these processes, we prospectively collected 307 patient-derived breast cancer samples (n = 195 early breast cancers (EBC) and n = 112 metastatic samples (MBC)). We assessed colony-forming activity in vitro by growing isolated cells in both primary (formation) and secondary (self-renewal) mammosphere culture, and tumour initiating activity in vivo through subcutaneous transplantation of fragments or cells into mice. Metastatic samples formed primary mammosphere colonies significantly more frequently than early breast cancers and had significantly higher primary mammosphere colony formation efficiency (0.9 % vs. 0.6 %; p < 0.0001). Tumour initiation in vivo was significantly higher in metastatic than early breast cancer samples (63 % vs. 38 %, p = 0.04). Of 144 breast cancer samples implanted in vivo, we established 20 stable patient-derived xenograft (PDX) models at passage 2 or greater. Lung metastases were detected in mice from 14 PDX models. Mammosphere colony formation in vitro significantly correlated with the ability of a tumour to metastasise to the lungs in vivo (p = 0.05), but not with subcutaneous tumour initiation. In summary, the breast cancer stem cell activities of colony formation and tumour initiation are increased in metastatic compared to early samples, and predict metastasis in vivo. These results suggest that breast stem cell activity will predict for poor outcome tumours, and therapy targeting this activity will improve outcomes for patients with metastatic disease.
Stability of alemtuzumab solutions at room temperature.
Goldspiel, Justin T; Goldspiel, Barry R; Grimes, George J; Yuan, Peng; Potti, Gopal
2013-03-01
The 24-hour stability of alemtuzumab solutions prepared at concentrations not included in the product label and stored in glass or polyolefin containers at room temperature was evaluated. Triplicate solutions of alemtuzumab (6.67, 40, and 120 μg/mL) in 0.9% sodium chloride were prepared in either glass bottles or polyolefin containers and stored at room temperature under normal fluorescent lighting conditions. The solutions were analyzed by a validated stability-indicating high-performance liquid chromatography (HPLC) assay at time zero and 8, 14, and 24 hours after preparation; solution pH values were measured and the containers visually inspected at all time points. Stability was defined as the retention of ≥90% of the initial alemtuzumab concentration. HPLC analysis indicated that the percentage of the initial alemtuzumab concentration retained was >90% for all solutions evaluated, with no significant changes over the study period. The most dilute alemtuzumab solution (6.67 μg/mL) showed some degradation (91% of the initial concentration retained at hour 24), whereas the retained concentration was >99% for all other preparations throughout the study period. Solution pH values varied by drug concentration but did not change significantly over 24 hours. No evidence of particle formation was detected in any solution by visual inspection at any time during the study. Solutions of alemtuzumab 6.67 μg/mL stored in glass bottles and solutions of 40 and 120 μg/mL stored in polyolefin containers were stable for at least 24 hours at room temperature.
NASA Astrophysics Data System (ADS)
Han, Inho; Vagaska, Barbora; Joo Park, Bong; Lee, Mi Hee; Jin Lee, Seung; Park, Jong-Chul
2011-06-01
Successful tissue integration of implanted medical devices depends on appropriate initial cellular response. In this study, the effect of helium atmospheric pressure glow discharge (He-APGD) treatment of titanium on selective protein adsorption and the initial attachment processes and focal adhesion formation of osteoprogenitor cells and stem cells were examined. Titanium disks were treated in a self-designed He-APGD system. Initial attachment of MC3T3-E1 mouse pre-osteoblasts and human mesenchymal stem cells (MSCs) was evaluated by MTT assay and plasma membrane staining followed by morphometric analysis. Fibronectin adsorption was investigated by Enzyme-Linked ImmunoSorbant Assay. MSCs cell attachment to treated and non-treated titanium disks coated with different proteins was verified also in serum-free culture. Organization of actin cytoskeleton and focal adhesions was evaluated microscopically. He-APGD treatment effectively modified the titanium surfaces by creating a super-hydrophilic surface, which promoted selectively higher adsorption of fibronectin, a protein of critical importance for cell/biomaterial interaction. In two different types of cells, the He-APGD treatment enhanced the number of attaching cells as well as their attachment area. Moreover, cells had higher organization of actin cytoskeleton and focal adhesions. Faster acceptance of the material by the progenitor cells in the early phases of tissue integration after the implantation may significantly reduce the overall healing time; therefore, titanium treatment with He-APGD seems to be an effective method of surface modification of titanium for improving its tissue inductive properties.
Right timing in formative program evaluation.
Hall, Jori; Freeman, Melissa; Roulston, Kathy
2014-08-01
Since many educational researchers and program developers have limited knowledge of formative evaluation, formative data may be underutilized during the development and implementation of an educational program. The purpose of this article is to explain how participatory, responsive, educative, and qualitative approaches to formative evaluation can facilitate a partnership between evaluators and educational researchers and program managers to generate data useful to inform program implementation and improvement. This partnership is critical, we argue, because it enables an awareness of when to take appropriate action to ensure successful educational programs or "kairos". To illustrate, we use examples from our own evaluation work to highlight how formative evaluation may facilitate opportune moments to (1) define the substance and purpose of a program, (2) develop understanding and awareness of the cultural interpretations of program participants, and (3) show the relevance of stakeholder experiences to program goals. Copyright © 2014 Elsevier Ltd. All rights reserved.
Zhu, Yan; Li, Guodong; Williams, Jessica A.; Buckley, Kyle; Tawfik, Ossama; Luyendyk, James P.
2016-01-01
Farnesoid X receptor (FXR) belongs to the nuclear receptor superfamily with its endogenous ligands bile acids. Mice with whole body FXR deficiency develop liver tumors spontaneously, but the underlying mechanism is unclear. Moreover, it is unknown whether FXR deficiency in liver alone serves as a tumor initiator or promoter during liver carcinogenesis. This study aims to evaluate the effects of hepatocyte-specific FXR deficiency (FXRhep−/−) in liver tumor formation. The results showed that FXRhep−/− mice did not show spontaneous liver tumorigenesis with aging (up to 24 mo of age). Therefore FXRhep−/− mice were fed a bile acid (cholic acid)-containing diet alone or along with a liver tumor initiator, diethylnitrosamine (DEN). Thirty weeks later, no tumors were found in wild-type or FXRhep−/− mice without any treatment or with DEN only. However, with cholic acid, while only some wild-type mice developed tumors, all FXRhep−/− mice presented with severe liver injury and tumors. Interestingly, FXRhep−/− mouse livers increased basal expression of tumor suppressor p53 protein, apoptosis, and decreased basal cyclin D1 expression, which may prevent tumor development in FXRhep−/− mice. However, cholic acid feeding reversed these effects in FXRhep−/− mice, which is associated with an increased cyclin D1 and decreased cell cycle inhibitors. More in-depth analysis indicates that the increased in cell growth might result from disturbance of the MAPK and JAK/Stat3 signaling pathways. In conclusion, this study shows that hepatic FXR deficiency may only serve as a tumor initiator, and increased bile acids is required for tumor formation likely by promoting cell proliferation. PMID:26744468
Slipping through the net: the paradox of nursing's electronic theses and dissertations.
Macduff, C; Goodfellow, L M; Nolfi, D; Copeland, S; Leslie, G D; Blackwood, D
2016-06-01
The study's main aim was to gain in-depth understanding of how nurse scholars engage with electronic theses and dissertations. Through elicitation of opinions about challenges and opportunities, and perceptions of future development, the study also aimed to influence the design of a new international web-based forum for learning and sharing information on this topic. Electronic theses and dissertations provide an opportunity to radically change the way in which graduate student research is presented, disseminated and used internationally. However, as revealed by a multi-national survey in 2011, many nurse scholars in vanguard universities have little awareness of how to find and exploit this ever-expanding global knowledge resource that is increasingly available free in full text format. Within this context more detailed understandings of nurse scholars' thinking and actions are required. A qualitative approach using a semi-structured interview guide was utilized to elicit perceptions from 14 nurse scholars. Thematic analysis of the interviewees' responses identified six major themes: initial exposure and effect; searching; accessing; handling; using; and evaluation. Insights were gained about the value of these resources and behaviours in using them as exemplars for structure, format and methodology. Despite the small study size, the findings added valuable new insights to the overview gained from the 2011 survey. These have been used to inform development of a new global initiative: the International Network for Electronic Theses and Dissertations in Nursing. Featuring an educational website (www.inetdin.net), this initiative aims to support and challenge nursing's policy makers, practitioners and especially educators to utilize this neglected but exponentially increasing wellspring of international nursing knowledge. © 2016 International Council of Nurses.
García García, Tránsito; Ventroux, Magali; Derouiche, Abderahmane; Bidnenko, Vladimir; Correia Santos, Sara; Henry, Céline; Mijakovic, Ivan; Noirot-Gros, Marie-Françoise; Poncet, Sandrine
2018-01-01
Bacillus subtilis cells can adopt different life-styles in response to various environmental cues, including planktonic cells during vegetative growth, sessile cells during biofilm formation and sporulation. While switching life-styles, bacteria must coordinate the progression of their cell cycle with their physiological status. Our current understanding of the regulatory pathways controlling the decision-making processes and triggering developmental switches highlights a key role of protein phosphorylation. The regulatory mechanisms that integrate the bacterial chromosome replication status with sporulation involve checkpoint proteins that target the replication initiator DnaA or the kinase phosphorelay controlling the master regulator Spo0A. B. subtilis YabA is known to interact with DnaA to prevent over-initiation of replication during vegetative growth. Here, we report that YabA is phosphorylated by YabT, a Ser/Thr kinase expressed during sporulation and biofilm formation. The phosphorylation of YabA has no effect on replication initiation control but hyper-phosphorylation of YabA leads to an increase in sporulation efficiency and a strong inhibition of biofilm formation. We also provide evidence that YabA phosphorylation affects the level of Spo0A-P in cells. These results indicate that YabA is a multifunctional protein with a dual role in regulating replication initiation and life-style switching, thereby providing a potential mechanism for cross-talk and coordination of cellular processes during adaptation to environmental change. PMID:29619013
García García, Tránsito; Ventroux, Magali; Derouiche, Abderahmane; Bidnenko, Vladimir; Correia Santos, Sara; Henry, Céline; Mijakovic, Ivan; Noirot-Gros, Marie-Françoise; Poncet, Sandrine
2018-01-01
Bacillus subtilis cells can adopt different life-styles in response to various environmental cues, including planktonic cells during vegetative growth, sessile cells during biofilm formation and sporulation. While switching life-styles, bacteria must coordinate the progression of their cell cycle with their physiological status. Our current understanding of the regulatory pathways controlling the decision-making processes and triggering developmental switches highlights a key role of protein phosphorylation. The regulatory mechanisms that integrate the bacterial chromosome replication status with sporulation involve checkpoint proteins that target the replication initiator DnaA or the kinase phosphorelay controlling the master regulator Spo0A. B. subtilis YabA is known to interact with DnaA to prevent over-initiation of replication during vegetative growth. Here, we report that YabA is phosphorylated by YabT, a Ser/Thr kinase expressed during sporulation and biofilm formation. The phosphorylation of YabA has no effect on replication initiation control but hyper-phosphorylation of YabA leads to an increase in sporulation efficiency and a strong inhibition of biofilm formation. We also provide evidence that YabA phosphorylation affects the level of Spo0A-P in cells. These results indicate that YabA is a multifunctional protein with a dual role in regulating replication initiation and life-style switching, thereby providing a potential mechanism for cross-talk and coordination of cellular processes during adaptation to environmental change.
NASA Astrophysics Data System (ADS)
Yoo, Sung-Moon; Song, Young-Joo; Park, Sang-Young; Choi, Kyu-Hong
2009-06-01
A formation flying strategy with an Earth-crossing object (ECO) is proposed to avoid the Earth collision. Assuming that a future conceptual spacecraft equipped with a powerful laser ablation tool already rendezvoused with a fictitious Earth collision object, the optimal required laser operating duration and direction histories are accurately derived to miss the Earth. Based on these results, the concept of formation flying between the object and the spacecraft is applied and analyzed as to establish the spacecraft's orbital motion design strategy. A fictitious "Apophis"-like object is established to impact with the Earth and two major deflection scenarios are designed and analyzed. These scenarios include the cases for the both short and long laser operating duration to avoid the Earth impact. Also, requirement of onboard laser tool's for both cases are discussed. As a result, the optimal initial conditions for the spacecraft to maintain its relative trajectory to the object are discovered. Additionally, the discovered optimal initial conditions also satisfied the optimal required laser operating conditions with no additional spacecraft's own fuel expenditure to achieve the spacecraft formation flying with the ECO. The initial conditions founded in the current research can be used as a spacecraft's initial rendezvous points with the ECO when designing the future deflection missions with laser ablation tools. The results with proposed strategy are expected to make more advances in the fields of the conceptual studies, especially for the future deflection missions using powerful laser ablation tools.
Formative Research in Educational Media.
ERIC Educational Resources Information Center
Hodapp, Timothy
This paper distinguishes between basic research, applied research, and evaluation. Evaluation is broken down into two types: summative and formative. The limitations of formative research are presented, followed by a discussion of the value of the formative researcher participating in the product planning process. The types of data which formative…
The Formation of a Sunspot Penumbra Sector in Active Region NOAA 12574
NASA Astrophysics Data System (ADS)
Li, Qiaoling; Yan, Xiaoli; Wang, Jincheng; Kong, DeFang; Xue, Zhike; Yang, Liheng; Cao, Wenda
2018-04-01
We present a particular case of the formation of a penumbra sector around a developing sunspot in the active region NOAA 12574 on 2016 August 11 by using the high-resolution data observed by the New Solar Telescope at the Big Bear Solar Observatory and the data acquired by the Helioseismic and Magnetic Imager and the Atmospheric Imaging Assembly on board the Solar Dynamics Observatory satellite. Before the new penumbra sector formed, the developing sunspot already had two umbrae with some penumbral filaments. The penumbra sector gradually formed at the junction of two umbrae. We found that the formation of the penumbra sector can be divided into two stages. First, during the initial stage of penumbral formation, the region where the penumbra sector formed always appeared blueshifted in a Dopplergram. The area, mean transverse magnetic field strength, and total magnetic flux of the umbra and penumbra sector all increased with time. The initial penumbral formation was associated with magnetic emergence. Second, when the penumbra sector appeared, the magnetic flux and area of the penumbra sector increased after the umbra’s magnetic flux and area decreased. These results indicate that the umbra provided magnetic flux for penumbral development after the penumbra sector appeared. We also found that the newly formed penumbra sector was associated with sunspot rotation. Based on these findings, we suggest that the penumbra sector was the result of the emerging flux that was trapped in the photosphere at the initial stage of penumbral formation, and when the rudimentary penumbra formed, the penumbra sector developed at the cost of the umbra.
Timmermans, Daniëlle R M; Ockhuysen-Vermey, Caroline F; Henneman, Lidewij
2008-12-01
Effective communication of health risks plays an important role in enabling patients to make adequate decisions. There is little--though contradictory--evidence to indicate which format is most effective for communicating risks, and which risk format is preferred by counselees. In an experiment, subjects were presented health scenarios and risk information in different formats (percentages, frequencies, and population figures) and asked to evaluate the risks and make a decision based on these. Different risk formats had different effects on respondents' evaluation of the health risks presented. Contrary to our expectation, population figures were not evaluated as being the easiest format for all decision problems. Population figures were shown to have the biggest affective impact, and risks presented as population figures were also evaluated as significantly greater than the risks presented in other formats. The format of the presented risks influenced their decision in only one out of four decision-making situations, although in a second situation there was a similar trend. This study suggests that the risk format plays a role in the decision-making process, although it remains unclear which format is the most effective in terms of understanding. More experimental studies based on a theoretical analysis of the factors that promote effective risk communication are needed in the general population as well as in clinical settings with patients actually experiencing the risks and making the decisions.
Replication Rate, Framing, and Format Affect Attitudes and Decisions about Science Claims.
Barnes, Ralph M; Tobin, Stephanie J; Johnston, Heather M; MacKenzie, Noah; Taglang, Chelsea M
2016-01-01
A series of five experiments examined how the evaluation of a scientific finding was influenced by information about the number of studies that had successfully replicated the initial finding. The experiments also tested the impact of frame (negative, positive) and numeric format (percentage, natural frequency) on the evaluation of scientific findings. In Experiments 1 through 4, an attitude difference score served as the dependent measure, while a measure of choice served as the dependent measure in Experiment 5. Results from a diverse sample of 188 non-institutionalized U.S. adults (Experiment 2) and 730 undergraduate college students (Experiments 1, 3, and 4) indicated that attitudes became more positive as the replication rate increased and attitudes were more positive when the replication information was framed positively. The results also indicate that the manner in which replication rate was framed had a greater impact on attitude than the replication rate itself. The large effect for frame was attenuated somewhat when information about replication was presented in the form of natural frequencies rather than percentages. A fifth study employing 662 undergraduate college students in a task in which choice served as the dependent measure confirmed the framing effect and replicated the replication rate effect in the positive frame condition, but provided no evidence that the use of natural frequencies diminished the effect.
Blaikie, L; Basketter, D A
1999-08-01
The predictive identification of respiratory allergenic potential is an important primary step in the safety evaluation of (novel) proteins, such as the enzymes used in a range of consumer laundry products. In the past this has been achieved by assessing the relative ability of proteins to give rise to the formation of anaphylactic antibody in the guinea pig. Recently, an alternative model has been proposed which assesses the formation of specific IgG1 antibody in a mouse intranasal test (MINT), the assumption being that specific IgG1 antibody is a surrogate for anaphylactic antibody in the mouse. This procedure has undergone successful initial intralaboratory and interlaboratory assessment. In the present work, the MINT has been evaluated in a more thorough intralaboratory study using eight enzymes plus ovalbumin. While the data generated with a reference enzyme protein, Alcalase, showed good reproducibility, results with the remaining eight proteins led to estimates of their relative antigenic or sensitization potential several of which were at variance from those derived from the guinea pig/ human experience. In consequence, it is concluded that the MINT requires substantial further investigation before it can be adopted as a model for the assessment of the relative ability of proteins to behave as respiratory allergens.
Occurrence of furan in coffee from Spanish market: Contribution of brewing and roasting.
Altaki, M S; Santos, F J; Galceran, M T
2011-06-15
In this work, we evaluated the occurrence of furan in brews obtained from regular, decaffeinated, and instant coffee and commercial packed capsules. For this purpose, a previously developed automated headspace solid-phase microextraction method coupled to gas chromatography-mass spectrometry (HS-SPME-GC-MS) was used. Initially, the influence of HS-SPME conditions on furan formation was evaluated. In addition, the effect of roasting conditions (temperature and time) used for coffee beans on furan formation was also studied. We found that low temperature and long roasting time (140°C and 20min) decreases the final furan content. Furan concentrations in regular ground coffee brews from an espresso coffee machine were higher (43-146ng/ml) than those obtained from a home drip coffee maker (20 and 78ng/ml), while decaffeinated coffee brews from a home drip coffee maker (14-65ng/ml) showed a furan concentration similar to that obtained from regular coffee. Relatively low concentrations of this compound (12-35ng/ml) were found in instant coffee brews, while commercial packed coffee capsules showed the highest concentrations (117-244ng/ml). Finally, the daily intake of furan through coffee consumption in Barcelona (Spain) (0.03-0.38μg/kg of body weight) was estimated. Copyright © 2010 Elsevier Ltd. All rights reserved.
Ramesh, Aruna; Ganguly, Rumpa; Qualters, Donna M
2014-09-01
This article describes the transition of an oral and maxillofacial radiology course from a traditional lecture format to an interactive case-based, team-based, interdisciplinary, and intraprofessional learning model in advanced dental education. Forty-four postdoctoral dental students were enrolled in the course over a twelve-week period in the fall semester 2012. The class consisted of U.S.- and foreign-trained dentists enrolled in advanced education programs in various dental disciplines. The course faculty preassigned interdisciplinary teams with four or five students in each. The class met once a week for an hour. Ten of the twelve sessions consisted of a team presentation, individual quiz, team quiz, and case discussion. Each member of a team completed peer evaluation of other team members during weeks six and twelve of the course. The final course grade was a composite of individual and team quiz grades, team presentation, and peer evaluation grades. The overall class average was 90.43. Ninety-five percent of the class (42/44) had total team grades equal to or greater than total individual quiz grades. The objective of creating a new case-based, team-based, interdisciplinary, intraprofessional learning model in advanced dental education was achieved, and the initial student perception of the new format was positive.
Muscat, Danielle M; Morony, Suzanne; Shepherd, Heather L; Smith, Sian K; Dhillon, Haryana M; Trevena, Lyndal; Hayen, Andrew; Luxford, Karen; Nutbeam, Don; McCaffery, Kirsten
2015-10-01
Given the scarcity of shared decision-making (SDM) interventions for adults with low literacy, we created a SDM training program tailored to this population to be delivered in adult education settings. Formative evaluation during program development included a review of the problem and previous efforts to address it, qualitative interviews with the target population, program planning and field testing. A comprehensive SDM training program was developed incorporating core SDM elements. The program aimed to improve students' understanding of SDM and to provide them with the necessary skills (understanding probabilistic risks and benefits, personal values and preferences) and self-efficacy to use an existing set of questions (the AskShareKnow questions) as a means to engage in SDM during healthcare interactions. There is an ethical imperative to develop SDM interventions for adults with lower literacy. Generic training programs delivered direct-to-consumers in adult education settings offer promise in a national and international environment where too few initiatives exist. Formative evaluation of the program offers practical insights into developing consumer-focused SDM training. The content of the program can be used as a guide for future efforts to engage consumers in SDM. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.
Hirakawa, Yuko; Jimbo, Ryo; Shibata, Yasuaki; Watanabe, Ikuya; Wennerberg, Ann; Sawase, Takashi
2013-08-01
The purpose of this study was to investigate the effect of photo-induced hydrophilic titanium dioxide (TiO₂) on serum fibronectin (sFN) attachment, and further to evaluate initial osseointegration responses in the dog mandibles. To apply the anatase TiO₂ film, plasma source ion implantation (PSII) method followed by annealing was employed for the titanium disks and implants, which were then illuminated with UV-A for 24 h for the experimental groups. Non-deposited titanium disks and implants were prepared for the control group. Surface characterization was performed using the interferometer and contact angle analyzer. The attachments of sFN were evaluated using fluorescence emission analysis. Thereafter both groups of implants were placed in the mandible of six beagle dogs. Bone response was investigated with histological and histomorphometrical analyses after periods of 2 and 4 weeks. The experimental groups exhibited strong hydrophilicity under UV-A illumination and showed significant improvement in sFN attachment. And further, the experimental implants enhanced the bone formation with the bone-to-implant contact of 42.7% after 2 weeks of healing (control: 28.4%). The combined applications of plasma fibronectin and PSII to produce hydrophilic titanium surfaces could accelerate early osseointegration. © 2012 John Wiley & Sons A/S.
Early formation of the Moon 4.51 billion years ago
Barboni, Melanie; Boehnke, Patrick; Keller, Brenhin; Kohl, Issaku E.; Schoene, Blair; Young, Edward D.; McKeegan, Kevin D.
2017-01-01
Establishing the age of the Moon is critical to understanding solar system evolution and the formation of rocky planets, including Earth. However, despite its importance, the age of the Moon has never been accurately determined. We present uranium-lead dating of Apollo 14 zircon fragments that yield highly precise, concordant ages, demonstrating that they are robust against postcrystallization isotopic disturbances. Hafnium isotopic analyses of the same fragments show extremely low initial 176Hf/177Hf ratios corrected for cosmic ray exposure that are near the solar system initial value. Our data indicate differentiation of the lunar crust by 4.51 billion years, indicating the formation of the Moon within the first ~60 million years after the birth of the solar system. PMID:28097222
Primeval galaxies and cold dark matter
NASA Technical Reports Server (NTRS)
Silk, Joseph; Szalay, Alexander S.
1987-01-01
In the context of the cold dark matter theory for the large-scale matter distribution, the onset of galaxy formation is a gradual process, with star formation being initiated at z = about 10 and reaching a peak for luminous galaxies at z = about 1. The mass function of galaxy cores matches the observed quasar luminosity function at z = 2-3. Primeval galaxies are envisaged as a collection of many interacting and merging clumps, attaining a peak luminosity that is an order of magnitude below that achieved in models in which galaxy formation is initiated abruptly. Hence, ongoing searches for primeval galaxies would not necessarily have been successful unless they are designed to find moderately low-luminosity, low-surface-brigtness extended objects at low redshift.
Effect of hypersaline cooling canals on aquifer salinization
Hughes, Joseph D.; Langevin, Christian D.; Brakefield-Goswami, Linzy
2010-01-01
The combined effect of salinity and temperature on density-driven convection was evaluated in this study for a large (28 km2) cooling canal system (CCS) at a thermoelectric power plant in south Florida, USA. A two-dimensional cross-section model was used to evaluate the effects of hydraulic heterogeneities, cooling canal salinity, heat transport, and cooling canal geometry on aquifer salinization and movement of the freshwater/saltwater interface. Four different hydraulic conductivity configurations, with values ranging over several orders of magnitude, were evaluated with the model. For all of the conditions evaluated, aquifer salinization was initiated by the formation of dense, hypersaline fingers that descended downward to the bottom of the 30-m thick aquifer. Saline fingers reached the aquifer bottom in times ranging from a few days to approximately 5 years for the lowest hydraulic conductivity case. Aquifer salinization continued after saline fingers reached the aquifer bottom and coalesced by lateral movement away from the site. Model results showed that aquifer salinization was most sensitive to aquifer heterogeneity, but was also sensitive to CCS salinity, temperature, and configuration.
Mobile drama in an instrumented museum: inducing group conversation via coordinated narratives
NASA Astrophysics Data System (ADS)
Callaway, Charles; Stock, Oliviero; Dekoven, Elyon; Noy, Kinneret; Citron, Yael; Dobrin, Yael
2012-03-01
Museum visits can be more enjoyable to small groups if they can be both social and educational experiences. One very rewarding aspect of a visit, especially those involving small groups such as families, is the unmediated group discussion that can ensue during a shared cultural experience. We present a situated, mobile museum system that delivers an hour-long drama to museum visitors. It perceives and analyzes group behavior, uses the result to dynamically deliver coordinated dramatic narrative presentations about the nearby museum exhibit, with the expected result of stimulating group discussion. To accomplish this, our drama-based presentations contain small, complementary differences in the content delivered to each participant, leveraging the narrative tension/release cycle of drama to naturally lead visitors to fill in missing pieces by interacting with friends, thus initiating a conversation. We present two evaluations for these story variations, one in a closed, non-mobile environment, and the other a formative evaluation to gauge how well the methodology used in the non-mobile evaluation performs in evaluating the fully implemented system in a real museum environment.
eHealth and mHealth initiatives in Bangladesh: a scoping study.
Ahmed, Tanvir; Lucas, Henry; Khan, Azfar Sadun; Islam, Rubana; Bhuiya, Abbas; Iqbal, Mohammad
2014-06-16
The health system of Bangladesh is haunted by challenges of accessibility and affordability. Despite impressive gains in many health indicators, recent evidence has raised concerns regarding the utilization, quality and equity of healthcare. In the context of new and unfamiliar public health challenges including high population density and rapid urbanization, eHealth and mHealth are being promoted as a route to cost-effective, equitable and quality healthcare in Bangladesh. The aim of this paper is to highlight such initiatives and understand their true potential. This scoping study applies a combination of research tools to explore 26 eHealth and mHealth initiatives in Bangladesh. A screening matrix was developed by modifying the framework of Arksey & O'Malley, further complemented by case study and SWOT analysis to identify common traits among the selected interventions. The WHO health system building blocks approach was then used for thematic analysis of these traits. Findings suggest that most eHealth and mHealth initiatives have proliferated within the private sector, using mobile phones. The most common initiatives include tele-consultation, prescription and referral. While a minority of projects have a monitoring and evaluation framework, less than a quarter have undertaken evaluation. Most of the initiatives use a health management information system (HMIS) to monitor implementation. However, these do not provide for effective sharing of information and interconnectedness among the various actors. There are extremely few individuals with eHealth training in Bangladesh and there is a strong demand for capacity building and experience sharing, especially for implementation and policy making. There is also a lack of research evidence on how to design interventions to meet the needs of the population and on potential benefits. This study concludes that Bangladesh needs considerable preparation and planning to sustain eHealth and mHealth initiatives successfully. Additional formative and operational research is essential to explore the true potential of the technology. Frameworks for regulation in regards to eHealth governance should be the aim of future research on the integration of eHealth and mHealth into the Bangladesh health system.
eHealth and mHealth initiatives in Bangladesh: A scoping study
2014-01-01
Background The health system of Bangladesh is haunted by challenges of accessibility and affordability. Despite impressive gains in many health indicators, recent evidence has raised concerns regarding the utilization, quality and equity of healthcare. In the context of new and unfamiliar public health challenges including high population density and rapid urbanization, eHealth and mHealth are being promoted as a route to cost-effective, equitable and quality healthcare in Bangladesh. The aim of this paper is to highlight such initiatives and understand their true potential. Methods This scoping study applies a combination of research tools to explore 26 eHealth and mHealth initiatives in Bangladesh. A screening matrix was developed by modifying the framework of Arksey & O’Malley, further complemented by case study and SWOT analysis to identify common traits among the selected interventions. The WHO health system building blocks approach was then used for thematic analysis of these traits. Results Findings suggest that most eHealth and mHealth initiatives have proliferated within the private sector, using mobile phones. The most common initiatives include tele-consultation, prescription and referral. While a minority of projects have a monitoring and evaluation framework, less than a quarter have undertaken evaluation. Most of the initiatives use a health management information system (HMIS) to monitor implementation. However, these do not provide for effective sharing of information and interconnectedness among the various actors. There are extremely few individuals with eHealth training in Bangladesh and there is a strong demand for capacity building and experience sharing, especially for implementation and policy making. There is also a lack of research evidence on how to design interventions to meet the needs of the population and on potential benefits. Conclusion This study concludes that Bangladesh needs considerable preparation and planning to sustain eHealth and mHealth initiatives successfully. Additional formative and operational research is essential to explore the true potential of the technology. Frameworks for regulation in regards to eHealth governance should be the aim of future research on the integration of eHealth and mHealth into the Bangladesh health system. PMID:24934164
Fhaner, Mathew; Zhao, Hong; Bian, Xiaochun; Galligan, James J.; Swain, Greg M.
2010-01-01
In order to increase the initial nucleation density for the growth of boron-doped diamond on platinum wires, we employed the novel nucleation process (NNP) originally developed by Rotter et al. and discussed by others [1–3]. This pretreatment method involves (i) the initial formation of a thin carbon layer over the substrate followed by (ii) ultrasonic seeding of this “soft” carbon layer with nanoscale particles of diamond. This two-step pretreatment is followed by the deposition of boron-doped diamond by microwave plasma-assisted CVD. Both the diamond seed particles and sites on the carbon layer itself function as the initial nucleation zones for diamond growth from an H2-rich source gas mixture. We report herein on the characterization of the pre-growth carbon layer formed on Pt as well as boron-doped films grown for 2, 4 and 6 h post NNP pretreatment. Results from scanning electron microscopy, Raman spectroscopy and electrochemical studies are reported. The NNP method increases the initial nucleation density on Pt and leads to the formation of a continuous diamond film in a shorter deposition time than is typical for wires pretreated by conventional ultrasonic seeding. The results indicate that the pregrowth layer itself consists of nanoscopic domains of diamond and functions well to enhance the initial nucleation of diamond without any diamond powder seeding. PMID:21617759
Research on the statically thrusting propeller
NASA Technical Reports Server (NTRS)
Eisenhuth, J. J.
1978-01-01
Methods for calculating the induced flow at propeller blades were analyzed by treating the wake formation as an initial problem in time. An unsteady vortex lattice technique was applied to the wake formation and the vortex core size was studied.
Structure of a bacterial RNA polymerase holoenzyme open promoter complex
DOE Office of Scientific and Technical Information (OSTI.GOV)
Bae, Brian; Feklistov, Andrey; Lass-Napiorkowska, Agnieszka
2015-09-08
Initiation of transcription is a primary means for controlling gene expression. In bacteria, the RNA polymerase (RNAP) holoenzyme binds and unwinds promoter DNA, forming the transcription bubble of the open promoter complex (RPo). We have determined crystal structures, refined to 4.14 Å-resolution, of RPo containing Thermus aquaticus RNAP holoenzyme and promoter DNA that includes the full transcription bubble. The structures, combined with biochemical analyses, reveal key features supporting the formation and maintenance of the double-strand/single-strand DNA junction at the upstream edge of the -10 element where bubble formation initiates. The results also reveal RNAP interactions with duplex DNA just upstreammore » of the -10 element and potential protein/DNA interactions that direct the DNA template strand into the RNAP active site. Addition of an RNA primer to yield a 4 base-pair post-translocated RNA:DNA hybrid mimics an initially transcribing complex at the point where steric clash initiates abortive initiation and σA dissociation.« less
Structure of a bacterial RNA polymerase holoenzyme open promoter complex
Bae, Brian; Feklistov, Andrey; Lass-Napiorkowska, Agnieszka; ...
2015-09-08
Initiation of transcription is a primary means for controlling gene expression. In bacteria, the RNA polymerase (RNAP) holoenzyme binds and unwinds promoter DNA, forming the transcription bubble of the open promoter complex (RPo). We have determined crystal structures, refined to 4.14 Å-resolution, of RPo containing Thermus aquaticus RNAP holoenzyme and promoter DNA that includes the full transcription bubble. The structures, combined with biochemical analyses, reveal key features supporting the formation and maintenance of the double-strand/single-strand DNA junction at the upstream edge of the -10 element where bubble formation initiates. The results also reveal RNAP interactions with duplex DNA just upstreammore » of the -10 element and potential protein/DNA interactions that direct the DNA template strand into the RNAP active site. Additionally a RNA primer to yield a 4 base-pair post-translocated RNA:DNA hybrid mimics an initially transcribing complex at the point where steric clash initiates abortive initiation and σ A dissociation.« less
NASA Astrophysics Data System (ADS)
Clyde, William C.; Khan, Intizar H.; Gingerich, Philip D.
2003-12-01
Initial continental collision between India and Asia is thought to have caused significant changes to global climate and biota, yet its timing and biogeographic consequences are uncertain. Structural and geophysical evidence indicates initial collision during the early Paleogene, but sedimentary evidence of this has been controversial owing to the intense deformation and metamorphism along the suture zone. Modern orders of mammals that appeared abruptly on northern continents coincident with the global warming event marking the Paleocene-Eocene boundary are hypothesized to have originated on the Indian subcontinent, but no relevant paleontological information has been available to test this idea. Here we present new paleomagnetic, sedimentologic, and paleontologic evidence to show that the lower Eocene Ghazij Formation of western Pakistan records continental sedimentation and mammalian dispersal associated with initial India-Asia collision. Our results are consistent with the initial collision occurring near the Paleocene-Eocene boundary, but modern orders of mammals appeared later in Indo-Pakistan and thus did not likely originate on the Indian subcontinent.
Keith, Rosalind E; Crosson, Jesse C; O'Malley, Ann S; Cromp, DeAnn; Taylor, Erin Fries
2017-02-10
Much research does not address the practical needs of stakeholders responsible for introducing health care delivery interventions into organizations working to achieve better outcomes. In this article, we present an approach to using the Consolidated Framework for Implementation Research (CFIR) to guide systematic research that supports rapid-cycle evaluation of the implementation of health care delivery interventions and produces actionable evaluation findings intended to improve implementation in a timely manner. To present our approach, we describe a formative cross-case qualitative investigation of 21 primary care practices participating in the Comprehensive Primary Care (CPC) initiative, a multi-payer supported primary care practice transformation intervention led by the Centers for Medicare and Medicaid Services. Qualitative data include observational field notes and semi-structured interviews with primary care practice leadership, clinicians, and administrative and medical support staff. We use intervention-specific codes, and CFIR constructs to reduce and organize the data to support cross-case analysis of patterns of barriers and facilitators relating to different CPC components. Using the CFIR to guide data collection, coding, analysis, and reporting of findings supported a systematic, comprehensive, and timely understanding of barriers and facilitators to practice transformation. Our approach to using the CFIR produced actionable findings for improving implementation effectiveness during this initiative and for identifying improvements to implementation strategies for future practice transformation efforts. The CFIR is a useful tool for guiding rapid-cycle evaluation of the implementation of practice transformation initiatives. Using the approach described here, we systematically identified where adjustments and refinements to the intervention could be made in the second year of the 4-year intervention. We think the approach we describe has broad application and encourage others to use the CFIR, along with intervention-specific codes, to guide the efficient and rigorous analysis of rich qualitative data. NCT02318108.
Constructive Student Feedback: Online vs. Traditional Course Evaluations
ERIC Educational Resources Information Center
Donovan, Judy; Mader, Cynthia E.; Shinsky, John
2010-01-01
Substantial efforts have been made recently to compare the effectiveness of traditional course formats to alternative formats (most often, online delivery compared to traditional on-site delivery). This study examines, not the delivery format but rather the evaluation format. It compares traditional paper and pencil methods for course evaluation…
Cyclopamine-induced synophthalmia in sheep: defining a critical window and toxicokinetic evaluation.
Welch, K D; Panter, K E; Lee, S T; Gardner, D R; Stegelmeier, B L; Cook, D
2009-07-01
Cyclopamine, a steroidal alkaloid, from the plant Veratrum californicum is teratogenic, causing a range of different birth defects. The critical window for cyclopamine-induced synophthalmia formation has been reported to be gestational day (GD) 14. The objectives of this study were to better describe cyclopamine-induced craniofacial deformities, to better define the window of susceptibility to synophthalmia formation, and to characterize cyclopamine toxicokinetics in sheep. Ewes were dosed i.v. with purified cyclopamine for toxicokinetic analysis. Another four groups of ewes were dosed orally twice daily with 0.88 g/kg of V. californicum on GD 13, 14 or 15 or consecutively on GD days 13-15. Pregnancy and pre-partum fetal malformations were determined by ultrasound imaging on GD 60. At parturition lambs were assessed for gross malformations. The elimination half-life of cyclopamine in ewes was determined to be 1.1 +/- 0.1 h. The rapid clearance of cyclopamine indicates that ingestion of V. californicum must occur during a very narrow window for synophthalmia formation to occur. Ewes dosed with V. californicum on GD 13 or 14 had lambs with various craniofacial malformations including cyclopia, maxillary dysplasia and mandibular micrognathia. Ewes dosed on GD 15 delivered normal lambs. Ewes dosed consecutively on GD 13-15 were not pregnant at GD 60 and Veratrum-induced embryonic death was assumed to be the cause. Interestingly, lambs with cyclopia were smaller, under-developed and appeared premature even though their twin appeared fully developed. Initial evaluations suggest this was due to placental dysplasia. 2009 by John Wiley & Sons, Ltd.
Federal Register 2010, 2011, 2012, 2013, 2014
2013-05-20
... formative and summative evaluations of the project; Note: The following Web site provides more information... plan, linked to the project's logic model, for a formative evaluation of the project's activities. The plan must describe how the formative evaluation will use clear performance objectives to ensure...
NASA Astrophysics Data System (ADS)
Menneken, M.; John, T.; Läufer, A.; Berndt, J.; Henjes-Kunst, F.; Giese, J.
2016-12-01
When reconstructing the formation and evolution of Earths earliest crust, one is still heavily reliant on information that can be gathered from detrital zircon grains, which have been proven to be a useful tool concerning the various isotopic, chemical, and mineralogical features that can be utilized within. However, detailed investigations have shown that some of these tracers might be prone to alteration and will not necessarily reflect conditions during formation [1, 2]. In this study, zircons and their host rocks from the Granite Harbour Intrusives (GHI) of northern Victoria Land, Antarctica, have been investigated with respect to regional evolution of continental crust as well as the reliability of zircon as a recorder of crustal formation. Here we present U-Pb, δ18O, trace element and inclusion data of zircons from Cambro-Ordovician granitoids, as well as geochemical analyses of accessory apatites. Our initial results show that even in I-type granitoids with a presumably simple formation history, U-Pb-age data and related isotopic, chemical, or mineralogical features have to be evaluated carefully in order to constrain the timing of magmatic events, inheritance or fluid alteration events. They do, for example, incorporate a large portion of recycled material, which is clearly reflected by a strong component of inherited U-Pb-zircon ages, but can also be inferred by comparing main- and trace-element compositions of apatite inclusions in zircon with accessory apatites. Apatite inclusions from all investigated samples for example, are clearly higher in F concentration, than their accessory counterparts. However, not all zircon grains record the youngest event, emphasizing that not only alteration might be a key factor to consider when evaluating zircon characteristics with respect to their host rock, but also, the timing and preservation of predating features. [1] Rasmussen et al. (2011) Metamorphic replacement of mineral inclusions in detrital zircon from Jack Hills, Australia: Implications for the Hadean Earth: Geology 39, 1143-1146. [2] Nemchin et al. (2006) Re-evaluation of the origin and evolution of > 4.2 Ga zircons from the Jack Hills metasedimentary rocks: Earth and Planetary Science Letters, v. 244, p. 218-233.
Pediatric trainees' engagement in the online nutrition curriculum: preliminary results.
Lewis, Kadriye O; Frank, Graeme R; Nagel, Rollin; Turner, Teri L; Ferrell, Cynthia L; Sangvai, Shilpa G; Donthi, Rajesh; Mahan, John D
2014-09-16
The Pediatric Nutrition Series (PNS) consists of ten online, interactive modules and supplementary educational materials that have utilized web-based multimedia technologies to offer nutrition education for pediatric trainees and practicing physicians. The purpose of the study was to evaluate pediatric trainees' engagement, knowledge acquisition, and satisfaction with nutrition modules delivered online in interactive and non-interactive formats. From December 2010 through August 2011, pediatric trainees from seventy-three (73) different U.S. programs completed online nutrition modules designed to develop residents' knowledge of counseling around and management of nutritional issues in children. Data were analyzed using SPSS version 19. Both descriptive and inferential statistics were used in comparing interactive versus non-interactive modules. Pretest/posttest and module evaluations measured knowledge acquisition and satisfaction. Three hundred and twenty-two (322) pediatric trainees completed one or more of six modules for a total of four hundred and forty-two (442) accessions. All trainees who completed at least one module were included in the study. Two-way analyses of variance (ANOVA) with repeated measures (pre/posttest by interactive/non-interactive format) indicated significant knowledge gains from pretest to posttest (p < 0.002 for all six modules). Comparisons between interactive and non-interactive formats for Module 1 (N = 85 interactive, N = 95 non-interactive) and Module 5 (N = 5 interactive, N = 16 non-interactive) indicated a parallel improvement from the pretest to posttest, with the interactive format significantly higher than the non-interactive modules (p < .05). Both qualitative and quantitative data from module evaluations demonstrated that satisfaction with modules was high. However, there were lower ratings for whether learning objectives were met with Module 6 (p < 0.03) and lecturer rating (p < 0.004) compared to Module 1. Qualitative data also showed that completion of the interactive modules resulted in higher resident satisfaction. This initial assessment of the PNS modules shows that technology-mediated delivery of a nutrition curriculum in residency programs has great potential for providing rich learning environments for trainees while maintaining a high level of participant satisfaction.
Global survey of star clusters in the Milky Way. VI. Age distribution and cluster formation history
NASA Astrophysics Data System (ADS)
Piskunov, A. E.; Just, A.; Kharchenko, N. V.; Berczik, P.; Scholz, R.-D.; Reffert, S.; Yen, S. X.
2018-06-01
Context. The all-sky Milky Way Star Clusters (MWSC) survey provides uniform and precise ages, along with other relevant parameters, for a wide variety of clusters in the extended solar neighbourhood. Aims: In this study we aim to construct the cluster age distribution, investigate its spatial variations, and discuss constraints on cluster formation scenarios of the Galactic disk during the last 5 Gyrs. Methods: Due to the spatial extent of the MWSC, we have considered spatial variations of the age distribution along galactocentric radius RG, and along Z-axis. For the analysis of the age distribution we used 2242 clusters, which all lie within roughly 2.5 kpc of the Sun. To connect the observed age distribution to the cluster formation history we built an analytical model based on simple assumptions on the cluster initial mass function and on the cluster mass-lifetime relation, fit it to the observations, and determined the parameters of the cluster formation law. Results: Comparison with the literature shows that earlier results strongly underestimated the number of evolved clusters with ages t ≳ 100 Myr. Recent studies based on all-sky catalogues agree better with our data, but still lack the oldest clusters with ages t ≳ 1 Gyr. We do not observe a strong variation in the age distribution along RG, though we find an enhanced fraction of older clusters (t > 1 Gyr) in the inner disk. In contrast, the distribution strongly varies along Z. The high altitude distribution practically does not contain clusters with t < 1 Gyr. With simple assumptions on the cluster formation history, the cluster initial mass function and the cluster lifetime we can reproduce the observations. The cluster formation rate and the cluster lifetime are strongly degenerate, which does not allow us to disentangle different formation scenarios. In all cases the cluster formation rate is strongly declining with time, and the cluster initial mass function is very shallow at the high mass end.
NASA Technical Reports Server (NTRS)
Miller, James G.
1997-01-01
In this Progress Report, we describe our further development of advanced ultrasonic nondestructive evaluation methods applied to the characterization of anisotropic materials. We present images obtained from experimental measurements of ultrasonic diffraction patterns transmitted through water only and transmitted through water and a thin woven composite. All images of diffraction patterns have been included on the accompanying CD-ROM in the JPEG format and Adobe TM Portable Document Format (PDF), in addition to the inclusion of hardcopies of the images contained in this report. In our previous semi-annual Progress Report (NAG 1-1848, December, 1996), we proposed a simple model to simulate the effect of a thin woven composite on an insonifying ultrasonic pressure field. This initial approach provided an avenue to begin development of a robust measurement method for nondestructive evaluation of anisotropic materials. In this Progress Report, we extend that work by performing experimental measurements on a single layer of a five-harness biaxial woven composite to investigate how a thin, yet architecturally complex, material interacts with the insonifying ultrasonic field. In Section 2 of this Progress Report we describe the experimental arrangement and methods for data acquisition of the ultrasonic diffraction patterns upon transmission through a thin woven composite. We also briefly describe the thin composite specimen investigated. Section 3 details the analysis of the experimental data followed by the experimental results in Section 4. Finally, a discussion of the observations and conclusions is found in Section 5.
ERIC Educational Resources Information Center
Felsenberg, Johannes; Dombrowski, Vincent; Eisenhardt, Dorothea
2012-01-01
Protein degradation is known to affect memory formation after extinction learning. We demonstrate here that an inhibitor of protein degradation, MG132, interferes with memory formation after extinction learning in a classical appetitive conditioning paradigm. In addition, we find an enhancement of memory formation when the same inhibitor is…
ERIC Educational Resources Information Center
Chen, Qiuxian; Kettle, Margaret; Klenowski, Val; May, Lyn
2013-01-01
Formative assessment is increasingly being implemented through policy initiatives in Chinese educational contexts. As an approach to assessment, formative assessment derives many of its key principles from Western contexts, notably through the work of scholars in the UK, the USA and Australia. The question for this paper is the ways that formative…
Numerical two-dimensional calculations of the formation of the solar nebula
NASA Technical Reports Server (NTRS)
Bodenheimer, Peter H.
1991-01-01
Numerical two dimensional calculations of the formation of the solar nebula are presented. The following subject areas are covered: (1) observational constraints of the properties of the initial solar nebula; (2) the physical problem; (3) review if two dimensional calculations of the formation phase; (4) recent models with hydrodynamics and radiative transport; and (5) further evolution of the system.
Singlet oxygen production in Chlamydomonas reinhardtii under heat stress.
Prasad, Ankush; Ferretti, Ursula; Sedlářová, Michaela; Pospíšil, Pavel
2016-02-01
In the current study, singlet oxygen formation by lipid peroxidation induced by heat stress (40 °C) was studied in vivo in unicellular green alga Chlamydomonas reinhardtii. Primary and secondary oxidation products of lipid peroxidation, hydroperoxide and malondialdehyde, were generated under heat stress as detected using swallow-tailed perylene derivative fluorescence monitored by confocal laser scanning microscopy and high performance liquid chromatography, respectively. Lipid peroxidation was initiated by enzymatic reaction as inhibition of lipoxygenase by catechol and caffeic acid prevented hydroperoxide formation. Ultra-weak photon emission showed formation of electronically excited species such as triplet excited carbonyl, which, upon transfer of excitation energy, leads to the formation of either singlet excited chlorophyll or singlet oxygen. Alternatively, singlet oxygen is formed by direct decomposition of hydroperoxide via Russell mechanisms. Formation of singlet oxygen was evidenced by the nitroxyl radical 2,2,6,6-tetramethylpiperidine-1-oxyl detected by electron paramagnetic resonance spin-trapping spectroscopy and the imaging of green fluorescence of singlet oxygen sensor green detected by confocal laser scanning microscopy. Suppression of singlet oxygen formation by lipoxygenase inhibitors indicates that singlet oxygen may be formed via enzymatic lipid peroxidation initiated by lipoxygenase.
Gum and deposit formation from jet-turbine and diesel fuels at 100 C
DOE Office of Scientific and Technical Information (OSTI.GOV)
Mayo, F.R.; Lan, B.Y.
1987-01-01
Rates of oxidation and gum formation for six hydrocarbons, three jet-turbine fuels and three diesel fuels have been measured at 100 C in the presence of t-Bu2O2 tert-butyl-peroxide as initiator. Four of six fuels oxidize faster at 100 C than in previous work at 130 C with initiator. Four any single substrate, the amount of gum produced for the oxygen absorbed is similar at 100 and 130 C even with large changes in rates and t-Bu2O2 concentrations. Thus, one mechanism of gum formation is intimately associated with oxidation. The effects of t-Bu2O2 concentration on the rates of oxygen absorption andmore » gum formation show that gum formation is associated with chain termination by two peroxy radicals. In general, the pure hydrocarbons have long kinetic chains and give good yields of hydroperoxides. The fuels give short kinetic chains and produce little hydroperoxide but but much more gum formation is the coupling of substrates by peroxides in the absence of oxygen. The mechanism, condensation of oxidation products from alkylnaphthalenes, is also proposed.« less
Investigation of IGES for CAD/CAE data transfer
NASA Technical Reports Server (NTRS)
Zobrist, George W.
1989-01-01
In a CAD/CAE facility there is always the possibility that one may want to transfer the design graphics database from the native system to a non-native system. This may occur because of dissimilar systems within an organization or a new CAD/CAE system is to be purchased. The Initial Graphics Exchange Specification (IGES) was developed in an attempt to solve this scenario. IGES is a neutral database format into which the CAD/CAE native database format can be translated to and from. Translating the native design database format to IGES requires a pre-processor and transling from IGES to the native database format requires a post-processor. IGES is an artifice to represent CAD/CAE product data in a neutral environment to allow interfacing applications, archive the database, interchange of product data between dissimilar CAD/CAE systems, and other applications. The intent here is to present test data on translating design product data from a CAD/CAE system to itself and to translate data initially prepared in IGES format to various native design formats. This information can be utilized in planning potential procurement and developing a design discipline within the CAD/CAE community.
Carrillo, Héctor; Fontdevila, Jorge
2011-12-01
The topic of same-sex sexual initiation has generally remained understudied in the literature on sexual identity formation among sexual minority youth. This article analyzes the narratives of same-sex sexual initiation provided by 76 gay and bisexual Mexican immigrant men who participated in interviews for the Trayectos Study, an ethnographic study of sexuality and HIV risk. These participants were raised in a variety of locations throughout Mexico, where they also realized their same-sex attraction and initiated their sexual lives with men. We argue that Mexican male same-sex sexuality is characterized by three distinct patterns of sexual initiation--one heavily-based on gender roles, one based on homosociality, and one based on object choice--which inform the men's interpretations regarding sexual roles, partner preferences, and sexual behaviors. We analyzed the social factors and forms of cultural/sexual socialization that lead sexual minority youth specifically to each of these three patterns of sexual initiation. Our findings confirm the importance of studying same-sex sexual initiation as a topic in its own right, particularly as a tool to gain a greater understanding of the diversity of same-sex sexual experiences and sexual identities within and among ethnic/cultural groups.
Wang, Shanshan; Shi, Mingxin; Zhu, Dongqing; Mathews, Ranjiv; Zheng, Zhengui
2018-03-01
To determine whether the guinea pig phallus would be an appropriate model of human penile development, we characterized the embryology and sexual differentiation of guinea pig external genitalia and attended to induce hypospadias in males and tubular urethra formation in females pharmacologically. The external genitalia of guinea pig were collected from genital swelling initiation to newborn stages, and scanning electronic microscopy and histology were performed to visualize the morphology and structure. Immunohistochemistry was used to determine the androgen receptor localization. Bicalutamide and methyltestosterone were given to pregnant dams to reveal the role and timing of androgen in guinea pig penile masculinization. Canalization and dorsal-to-ventral movement of the urethral canal develops the urethral groove in both sexes, and then the males perform distal-opening-proximal-closing to form tubular urethra. More nuclear-localized androgen receptor is found in proximal genital tubercles of males than in females at (E) 29. Antiandrogen treatment at E26-E30 can cause hypospadias, and methyltestosterone administration at E27-E31 can induce tubular urethra formation in females. Fetal development of the guinea pig phallus is homologous to that of humans. Although guinea pig has structures similar to mouse, the urethral groove and the tubular urethra formation are more similar to humans. Antiandrogen treatment causes hypospadias in males and additional androgen induces tubular urethra formation in females. Thus, guinea pig is an appropriate model for further study of cellular and molecular mechanisms involved in distal-opening-proximal-closing in tubular urethra formation and the evaluation of the pathophysiological processes of hypospadias. Published by Elsevier Inc.
Identification of tumor-initiating cells derived from two canine rhabdomyosarcoma cell lines
KISHIMOTO, Takuya Evan; YASHIMA, Shoko; NAKAHIRA, Rei; ONOZAWA, Eri; AZAKAMI, Daigo; UJIKE, Makoto; OCHIAI, Kazuhiko; ISHIWATA, Toshiyuki; TAKAHASHI, Kimimasa; MICHISHITA, Masaki
2017-01-01
Cancer stem cells or tumor-initiating cells (TICs) are a small subpopulation of cells that have the capacity to self-renew, differentiate and initiate tumors. These cells may function in tumor initiation, aggression and recurrence. Whether spheres derived from canine rhabdomyosarcoma cells have stem cell-like properties is unclear. We induced sphere formation in the canine rhabdomyosarcoma cell lines, CMS-C and CMS-J, and characterized the spheres in vitro and in vivo. Sphere-forming cells were more resistant to vincristine, mitoxantrone and doxorubicin than adherent cells. Xenograft transplantation demonstrated that 1 × 103 sphere-forming cells derived from CMS-C were sufficient for tumor formation. The sphere assay showed that the sphere-forming cells were present in these tumors. These results suggest that the spheres derived from canine rhabdomyosarcoma cells may possess characteristics of TICs. This study provides the foundation for elucidating the contribution of TICs to rhabdomyosarcoma tumorigenesis. PMID:28529244
Identification of tumor-initiating cells derived from two canine rhabdomyosarcoma cell lines.
Kishimoto, Takuya Evan; Yashima, Shoko; Nakahira, Rei; Onozawa, Eri; Azakami, Daigo; Ujike, Makoto; Ochiai, Kazuhiko; Ishiwata, Toshiyuki; Takahashi, Kimimasa; Michishita, Masaki
2017-07-07
Cancer stem cells or tumor-initiating cells (TICs) are a small subpopulation of cells that have the capacity to self-renew, differentiate and initiate tumors. These cells may function in tumor initiation, aggression and recurrence. Whether spheres derived from canine rhabdomyosarcoma cells have stem cell-like properties is unclear. We induced sphere formation in the canine rhabdomyosarcoma cell lines, CMS-C and CMS-J, and characterized the spheres in vitro and in vivo. Sphere-forming cells were more resistant to vincristine, mitoxantrone and doxorubicin than adherent cells. Xenograft transplantation demonstrated that 1 × 10 3 sphere-forming cells derived from CMS-C were sufficient for tumor formation. The sphere assay showed that the sphere-forming cells were present in these tumors. These results suggest that the spheres derived from canine rhabdomyosarcoma cells may possess characteristics of TICs. This study provides the foundation for elucidating the contribution of TICs to rhabdomyosarcoma tumorigenesis.
Stem cell activation by light guides plant organogenesis.
Yoshida, Saiko; Mandel, Therese; Kuhlemeier, Cris
2011-07-01
Leaves originate from stem cells located at the shoot apical meristem. The meristem is shielded from the environment by older leaves, and leaf initiation is considered to be an autonomous process that does not depend on environmental cues. Here we show that light acts as a morphogenic signal that controls leaf initiation and stabilizes leaf positioning. Leaf initiation in tomato shoot apices ceases in the dark but resumes in the light, an effect that is mediated through the plant hormone cytokinin. Dark treatment also affects the subcellular localization of the auxin transporter PIN1 and the concomitant formation of auxin maxima. We propose that cytokinin is required for meristem propagation, and that auxin redirects cytokinin-inducible meristem growth toward organ formation. In contrast to common wisdom over the last 150 years, the light environment controls the initiation of lateral organs by regulating two key hormones: auxin and cytokinin.
Stem cell activation by light guides plant organogenesis
Yoshida, Saiko; Mandel, Therese; Kuhlemeier, Cris
2011-01-01
Leaves originate from stem cells located at the shoot apical meristem. The meristem is shielded from the environment by older leaves, and leaf initiation is considered to be an autonomous process that does not depend on environmental cues. Here we show that light acts as a morphogenic signal that controls leaf initiation and stabilizes leaf positioning. Leaf initiation in tomato shoot apices ceases in the dark but resumes in the light, an effect that is mediated through the plant hormone cytokinin. Dark treatment also affects the subcellular localization of the auxin transporter PIN1 and the concomitant formation of auxin maxima. We propose that cytokinin is required for meristem propagation, and that auxin redirects cytokinin-inducible meristem growth toward organ formation. In contrast to common wisdom over the last 150 years, the light environment controls the initiation of lateral organs by regulating two key hormones: auxin and cytokinin. PMID:21724835
Grotmol, Sindre; Nordvik, Kari; Kryvi, Harald; Totland, Geir K
2005-05-01
This study shows that segmental expression of alkaline phosphatase (ALP) activity by the notochord of the Atlantic salmon (Salmo salar L.) coincides with the initial mineralization of the vertebral body (chordacentrum), and precedes ALP expression by presumed somite-derived cells external to the notochordal sheath. The early expression of ALP indicates that the notochord plays an instructive role in the segmental patterning of the vertebral column. The chordacentra form segmentally as mineralized rings within the notochordal sheath, and ALP activity spreads within the chordoblast layer from ventral to dorsal, displaying the same progression and spatial distribution as the mineralization process. No ALP activity was observed in sclerotomal mesenchyme surrounding the notochordal sheath during initial formation of the chordacentra. Our results support previous findings indicating that the chordoblasts initiate a segmental differentiation of the notochordal sheath into chordacentra and intervertebral regions.
Nearest pattern interaction and global pattern formation
NASA Astrophysics Data System (ADS)
Jeong, Seong-Ok; Moon, Hie-Tae; Ko, Tae-Wook
2000-12-01
We studied the effect of nearest pattern interaction on a global pattern formation in a two-dimensional space, where patterns are to grow initially from a noise in the presence of a periodic supply of energy. Although our approach is general, we found that this study is relevant in particular to the pattern formation on a periodically vibrated granular layer, as it gives a unified perspective of the experimentally observed pattern dynamics such as oscillon and stripe formations, skew-varicose and crossroll instabilities, and also a kink formation and decoration.
NASA Astrophysics Data System (ADS)
Bykovsky, A. Yu; Sherbakov, A. A.
2016-08-01
The C-valued Allen-Givone algebra is the attractive tool for modeling of a robotic agent, but it requires the consensus method of minimization for the simplification of logic expressions. This procedure substitutes some undefined states of the function for the maximal truth value, thus extending the initially given truth table. This further creates the problem of different formal representations for the same initially given function. The multi-criteria optimization is proposed for the deliberate choice of undefined states and model formation.
Initial stage of nucleation-mediated crystallization of a supercooled melt
NASA Astrophysics Data System (ADS)
Chernov, A. A.; Pil'nik, A. A.; Islamov, D. R.
2016-09-01
The kinetic model of nucleation-mediated crystallization of a supercooled melt is presented in this work. It correctly takes into account the change in supercooling of the initial phase in the process of formation and evolution of a new phase. The model makes it possible to find the characteristic time of the process, time course of the crystal phase volume, solidified material microstructure. The distinctive feature of the model is the use of the "forbidden" zones in the volume where the formation of new nucleation centers is suppressed.
Engineering calcium oxalate crystal formation in Arabidopsis
USDA-ARS?s Scientific Manuscript database
Many plants accumulate crystals of calcium oxalate. Just how these crystals form remains unknown. To gain insight into the mechanisms regulating calcium oxalate crystal formation, a crystal engineering approach was initiated utilizing the non-crystal accumulating plant, Arabidopsis. The success of t...
Ralstonia insidiosa induces cell aggregation by Listeria monocytogenes
USDA-ARS?s Scientific Manuscript database
Biofilm formation is an important strategy for foodborne bacterial pathogens to survive in stressful environments such as fresh produce processing facilities. Bacterial cell aggregation strongly promotes the initiation of microcolonies and the formation of biofilms on abiological surfaces. We previ...
DOE Office of Scientific and Technical Information (OSTI.GOV)
Xing, Rong; Dagle, Vanessa Lebarbier; Flake, Matthew
In this study we examine feasibility for steam reforming the mixed oxygenate aqueous fraction derived from mildly hydrotreated fast pyrolysis bio-oils. Catalysts selective towards hydrogen formation and resistant to carbon formation utilizing feeds with relatively low steam-to-carbon (S/C) ratios are desired. Rh (5 wt%), Pt (5 wt%), Ru (5 wt%), Ir (5 wt%), Ni (15 wt%), and Co (15 wt%) metals supported on MgAl 2O 4 were evaluated for catalytic performance at 500°C and 1 atm using a complex feed mixture comprising of acids, polyols, cycloalkanes, and phenolic compounds. The Rh catalyst was found to be the most active andmore » resistant to carbon formation. The Ni and Co catalysts were found to be more active than the other noble metal catalysts investigated (Pt, Ru, and Ir). However, Ni was found to form significantly more carbon (coke) on the catalyst surface. Furthermore, Co was found to be the most selective towards H 2 formation. Evaluating the effect of temperature on stability for the Rh catalyst we found that catalyst stability was best when operated at 500°C as compared to the higher temperatures investigated (700, 800°C). When operating at 700°C significantly more graphitic formation was observed on the spent catalyst surface. Operating at 800°C resulted in reactor plugging as a result of thermal decomposition of the reactants. Thus, a concept analogous to the petroleum industries’ use of a pre-reformer, operated at approximately 500°C for steam reforming of the heavier naphtha components, followed by a high temperature methane reforming operated in the 600-850°C temperature range, could be applied in the case of steam reforming biomass derived oxygenates. Moreover, stability evaluations were performed over the Rh, Ni, and Co catalysts at 500°C and 1 atm, under similar initial conversions, reveal the Co catalyst to be the most stable and selective towards H 2 production. Conversion and selectivity to CH 4 over Co remained relatively stable at approximately 80% and 1.2%, respectively. By contrast, the Rh and Ni catalysts CH 4 selectivity’s were approximately 7-8%. Thus suggesting that a Co type catalyst may be more suitable for the steam reforming of biomass derived oxygenates as compared to the more conventional Ni and Rh type steam reforming catalysts. However, deposition of carbon on the surface was observed. High resolution TEM on the spent catalysts revealed the formation of graphitic carbon on the Rh catalyst, and filamentous carbon formation was observed on both the Ni and Co catalysts, albeit less pronounced on Co. Thus there is certainly opportunity for improvement in Co catalyst design and/or with process optimization.« less
Multifractal-based nuclei segmentation in fish images.
Reljin, Nikola; Slavkovic-Ilic, Marijeta; Tapia, Coya; Cihoric, Nikola; Stankovic, Srdjan
2017-09-01
The method for nuclei segmentation in fluorescence in-situ hybridization (FISH) images, based on the inverse multifractal analysis (IMFA) is proposed. From the blue channel of the FISH image in RGB format, the matrix of Holder exponents, with one-by-one correspondence with the image pixels, is determined first. The following semi-automatic procedure is proposed: initial nuclei segmentation is performed automatically from the matrix of Holder exponents by applying predefined hard thresholding; then the user evaluates the result and is able to refine the segmentation by changing the threshold, if necessary. After successful nuclei segmentation, the HER2 (human epidermal growth factor receptor 2) scoring can be determined in usual way: by counting red and green dots within segmented nuclei, and finding their ratio. The IMFA segmentation method is tested over 100 clinical cases, evaluated by skilled pathologist. Testing results show that the new method has advantages compared to already reported methods.
Development of nickel-metal hydride cell: An update
NASA Technical Reports Server (NTRS)
Kuwajima, S.; Kusawake, Hiroaki; Nakatani, Kensuke; Yano, Y.
1994-01-01
This paper presents in viewgraph format an overview of NASDA's evaluation of commercial nickel metal-hydride (Ni-MH) cells and the development and testing of Ni-MH cells for use in space. The commercial cells are concluded to be feasible and suitable for use in LEO; for GEO, the durability for overcharge is needed because long-term charge retention is required. For the aerospace Ni-MH cell design, two activation procedures are applied to evaluate the effect of the difference in the amount of overcharge protection and precharge. Specific energy of the Ni-MH cell is nearly accomplished at 50 Wh/kg. Initial characteristics indicate the effect derived from precharge. Thirty-five amp-hour class Ni-MH cells have good performance for LEO cycle of 25 and 40 percent DOD up to 3000 cycles as similar to commercial cells. The effect of the difference in the amount of overcharge protection will appear in life test.
Peer-to-peer communication, cancer prevention, and the internet
Ancker, Jessica S.; Carpenter, Kristen M.; Greene, Paul; Hoffmann, Randi; Kukafka, Rita; Marlow, Laura A.V.; Prigerson, Holly G.; Quillin, John M.
2013-01-01
Online communication among patients and consumers through support groups, discussion boards, and knowledge resources is becoming more common. In this paper, we discuss key methods through which such web-based peer-to-peer communication may affect health promotion and disease prevention behavior (exchanges of information, emotional and instrumental support, and establishment of group norms and models). We also discuss several theoretical models for studying online peer communication, including social theory, health communication models, and health behavior models. Although online peer communication about health and disease is very common, research evaluating effects on health behaviors, mediators, and outcomes is still relatively sparse. We suggest that future research in this field should include formative evaluation and studies of effects on mediators of behavior change, behaviors, and outcomes. It will also be important to examine spontaneously emerging peer communication efforts to see how they can be integrated with theory-based efforts initiated by researchers. PMID:19449267
Design and Evaluation of a Cross-Cultural Training System
NASA Technical Reports Server (NTRS)
Santarelli, Thomas; Stagl, Kevin C.
2011-01-01
Cross-cultural competency, and the underlying communication and affective skills required to develop such expertise, is becoming increasingly important for a wide variety of domains. To address this need, we developed a blended learning platform which combines virtual role-play with tutorials, assessment and feedback. A Middle-Eastern Curriculum (MEC) exemplar for cross-cultural training U.S. military personnel was developed to guide the refinement of an existing game-based training platform. To complement this curriculum, we developed scenario authoring tools to enable end-users to define training objectives, link performance measures and feedback/remediation to these objectives, and deploy experiential scenarios within a game-based virtual environment (VE). Lessons learned from the design and development of this exemplar cross-cultural competency curriculum, as well as formative evaluation results, are discussed. Initial findings suggest that the underlying training technology promotes deep levels of semantic processing of the key information of relevant cultural and communication skills.
On the formation modes in vortex interaction for multiple co-axial co-rotating vortex rings
NASA Astrophysics Data System (ADS)
Qin, Suyang; Liu, Hong; Xiang, Yang
2018-01-01
Interaction among multiple vortices is of particular importance to biological locomotion. It plays an essential role in the force and energy capture. This study examines the motion and dynamics of multiple co-axial co-rotating vortex rings. The vortex rings, which have the same formation time, are successively generated in a piston-cylinder apparatus by accurately controlling the interval time. The flow fields are visualized by the finite-time Lyapunov exponent and then repelling Lagrangian coherent structures (r-LCSs) are determined. Two types of vortex interactions ("strong" and "weak") are defined by investigating the r-LCSs: a strong interaction is indicated by connected r-LCSs showing a channel for fluid transport (termed as a "flux window"); a weak interaction is indicated by disconnected r-LCSs between the vortex rings. For strong interaction, leapfrogging and merger of vortex rings can happen in the later stage of the evolution process; however, the rings are separated for weak interaction. Two distinct formation modes, the formation enhancement mode (FEM) and formation restraint mode (FRM), refer to the effect of one or multiple vortex ring(s) on the initial circulation of the subsequently formed vortex ring. In the FEM, the circulation of a vortex ring is larger than that of an isolated (without interaction) vortex ring. On the other hand, the situation is opposite in the FRM. A dimensionless number reflecting the interaction mechanism, "structure stretching number" S*, is proposed, which evaluates the induced effect of the wake vortices on the formation of a vortex ring. A limiting S* (SL*=(2 ±0.4 ) ×1 0-4) is the bifurcation point of the two formation modes. The augmentation of circulation reaches up to 10% for the FEM when S*
Parent education interventions designed to support the transition to parenthood: A realist review.
Gilmer, Cyndi; Buchan, Judy L; Letourneau, Nicole; Bennett, Claudine T; Shanker, Stuart G; Fenwick, Anne; Smith-Chant, Brenda
2016-07-01
Public health nurses use parent education programmes to support individuals' transition to parenthood. A wide array of these programmes exists; however, the approach must be accommodated by resources available in a publicly funded system. For example, some new-parent education approaches use 1:1 home visiting (with a nurse or trained lay-home visitor) but the costs of this intensive approach can be prohibitive. Because of this limitation there is an interest in identifying effective and efficient new parent educational approaches that can realistically be provided at a universal level. Unfortunately, there is a lack of high-quality evaluation identifying programmes or educational processes that meet these criteria. To identify potentially effective new-parenting education interventions that could be implemented at a population level during the transition to parenthood period. Realist synthesis. Medline, CINAHL, ERIC, PsycINFO, Sociological Abstracts, grey literature. A realist review method generated a total of 72 papers that were used to inform the results. A three-pronged approach was used incorporating an initial search (6), a database search using applicable keywords and MeSH headings (58), and review of literature identified by advisory group (8 grey literature). An 'implementation chain' was developed to outline the overall logic and process behind parent education interventions and to guide the analysis. Seventy-two papers informed this review: 13 systematic reviews/meta-analyses, 34 intervention studies, 9 opinion papers, 8 programme reviews, and 8 grey literature reports. There was no compelling evidence to suggest that a single educational programme or delivery format was effective at a universal level. Some inherent issues were identified. For example, adult learning principles were overlooked and theories of parent-child interaction were not in evidence. No direct links between universal new-parent education programmes and child development outcomes were established. Programme reach and attrition were key challenges. Programme evaluation criteria were inconsistent, with an over-reliance on parent satisfaction or self-reported intention to change behaviour. There was evidence that effective facilitators helped increase parents' perceived satisfaction with programmes. It is unlikely that a single standardized format or programme will meet all the specific learning needs of parents. Multiple approaches that will allow people to access information or education at a time and in a format that suits them may be of value. The importance of the transition to parenthood and its impact on parent and child wellbeing warrant careful consideration of current programming and careful evaluation of future initiatives. Copyright © 2016 Elsevier Ltd. All rights reserved.
Bogale, Gebeyehu W; Boer, Henk; Seydel, Erwin R
2010-07-01
In the style of radio programmes, we developed three episodes of audio HIV prevention education for illiterate women in Ethiopia. We used social-oriented presentation formats, such as discussion between women on HIV prevention, and expert-oriented presentation formats, such as an interview with a male doctor. The aim of this study was to assess the relation between evaluation of presentation formats and overall liking of episodes, which is important for persuasive effects. Thirty women from rural Amhara listened to the episodes and, after listening, female data collectors interviewed the women on evaluation of presentation formats, overall liking of episodes, identification with the characters and convincingness. Evaluation of social-oriented presentation formats was strongly related to overall liking of episodes, but evaluation of expert-oriented presentation formats was not. This relation was mediated through convincingness and not through identification. We conclude that social-oriented presentation formats make messages more convincing and, consequently, improve overall liking and persuasive impact.
NASA Technical Reports Server (NTRS)
Liu, Y.; Nyquist, L.; Wiesmann, H.; Shih, C.; Schwandt, C.; Takeda, H.
2003-01-01
The largest group of iron meteorites, IAB, is distinguished by the presence of diverse silicate inclusions. In principle, Rb-Sr and Sm-Nd radiometric dating of these silicate inclusions by internal isochron techniques can determine both the times of melting and parent/daughter ratios in the precursor materials via initial Sr-87/Sr-86 and Nd-143/Nd-144 ratios. The Sr-87/Sr-86 and Nd-143/Nd-144 ratios could distinguish chondritic precursors from already differentiated silicates. We reported Rb-Sr and Sm-Nd internal ischron ages of 4.52+/-0.03 Ga and 4.50+/-0.04 Ga, respectively, for plagioclase-diopside-rich material in the Caddo County IAB iron meteorite. These results are essentially identical to literature values of its Ar-Ar age of 4.520+/-0.005 Ga and its Sm-Nd age of 4.53+/-0.02 Ga. The purpose of this study is to evaluate the formation and evolution of silicate inclusions in IAB iron meteorites by determination of their initial Sr-87/Sr-86 ratios combined with higher-resolution chronology and mineralogical and geochemical studies.
Three Decades of Research on Computer Applications in Health Care
Michael Fitzmaurice, J.; Adams, Karen; Eisenberg, John M.
2002-01-01
The Agency for Healthcare Research and Quality and its predecessor organizations—collectively referred to here as AHRQ—have a productive history of funding research and development in the field of medical informatics, with grant investments since 1968 totaling $107 million. Many computerized interventions that are commonplace today, such as drug interaction alerts, had their genesis in early AHRQ initiatives. This review provides a historical perspective on AHRQ investment in medical informatics research. It shows that grants provided by AHRQ resulted in achievements that include advancing automation in the clinical laboratory and radiology, assisting in technology development (computer languages, software, and hardware), evaluating the effectiveness of computer-based medical information systems, facilitating the evolution of computer-aided decision making, promoting computer-initiated quality assurance programs, backing the formation and application of comprehensive data banks, enhancing the management of specific conditions such as HIV infection, and supporting health data coding and standards initiatives. Other federal agencies and private organizations have also supported research in medical informatics, some earlier and to a greater degree than AHRQ. The results and relative roles of these related efforts are beyond the scope of this review. PMID:11861630
Vadaparampil, Susan T.; Simmons, Vani N.; Lee, Ji-Hyun; Malo, Teri; Klasko, Lynne; Rodriguez, Maria; Waddell, Rhonda; Gwede, Clement K.; Meade, Cathy D.
2014-01-01
Background Journal clubs may enhance the knowledge and skills necessary to engage in community-based participatory research (CBPR) that will ultimately impact cancer health disparities. This article: (1) describes an innovative approach to adapting the traditional journal club format to meet community and academic participants’ needs, (2) presents evaluation data, and (3) explores whether responses differed between academic and community members. Methods Five journal clubs occurred between February 2011 and May 2012 as a training activity of a regional cancer health disparities initiative. Each journal club was jointly planned and facilitated by an academic member in collaboration with a community partner. Attendees were recruited from academic programs across the Moffitt Cancer Center/university and community partners. Responses to a 13-item evaluation of each journal club session were compared to assess whether certain topics were evaluated more favorably, and explore differences between academic and community participants’ assessment of the topic relevance. Results Evaluations were positive (mean ratings >4 out of 5) on most items and overall. No statistically significant differences were observed between academic and community members’ ratings. Key overlapping interests by community partners and academic researchers/trainees for future journal club topics included discussing real-world CBPR examples and methods for involving the community in research. Conclusions Although the initial goal was to use journal clubs as an educational tool to increase CBPR knowledge and skills of junior faculty trainees, results suggest mutual academic-community benefit and interest in learning more about CBPR as a way to reduce cancer health disparities. PMID:24078328
NASA Astrophysics Data System (ADS)
Wu, Cheng-Yueh; Chiu, Yung-Cheng; Huang, Yi-Jyun; Hsieh, Bieng-Zih
2017-04-01
The future energy police of Taiwan will heavily rely on the clean energy, including renewable energy and low-carbon energy, to meet the target of mitigating CO2 emission. In addition to developing the renewable energies like solar and wind resources, Taiwan will increase the natural gas consumption to obtain enough electrical power with low-carbon emission. The vast resources of gas hydrates recognized in southwestern offshore Taiwan makes a great opportunity for Taiwan to have own energy resources in the future. Therefore, Taiwan put significant efforts on the evaluation of gas hydrate reserves recently. Production behavior of natural gas dissociated from gas hydrate deposits is an important issue to the hydrate reserves evaluation. The depressurization method is a useful engineering recovery method for gas production from a class-3 type hydrate deposit. The dissociation efficiency will be affected by the pressure drawdown disturbance. However, when the pore pressure of hydrate deposits is depressurized for gas production, the rock matrix will surfer more stresses and the formation deformation might be occurred. The purpose of this study was to investigate the effects of geomechanical mechanism on the gas production from a class-3 hydrate deposit using depressurization method. The case of a class-3 type hydrate deposit of Four-Way-Closure Ridge was studied. In this study a reservoir simulator, STARS, was used. STARS is a multiphase flow, heat transfer, geo-chemical and geo-mechanical mechanisms coupling simulator which is capable to simulate the dissociation/reformation of gas hydrate and the deformation of hydrate reservoirs and overburdens. The simulating ability of STARTS simulator was validated by duplicating the hydrate comparison projects of National Energy Technology Lab. The study target, Four-Way-Closure (FWC) Ridge hydrate deposit, was discovered by the bottom simulating reflectors (BSRs). The geological parameters were collected from the geological and geophysical studies and the geo-mechanical data were analogized from Japan's hydrate production case. The first step for the geological modelling was to digitize the structure map of FWC Ridge and built a grid system for the reservoir. The formation parameters, such as formation thickness, porosity and permeability, the phase behavior parameters, rock-fluid parameters, initial conditions (including formation pressure, temperature and hydrate saturation), geo-mechanical parameters were assigned into each grid. In this case we used a horizontal well with specific operating conditions to produce water and dissociated gas from the reservoir. The sensitivity analyses on geological and geo-mechanical parameters were conducted in this study. The case of different pressure drop showed that the recovery factor (RF) was 2.50%, 13.50% and 20.47% when the pressure drop of 60%, 70% and 75% from the initial reservoir pressure was used respectively. Based on the case of pressure drop of 75% (from the initial reservoir pressure), the RF was 35.13%, 25.9%, 20.47% and 16.65% when the initial hydrate saturation of 30%, 40%, 50% and 60% was assumed respectively. The greater formation permeability, the better gas recovery. The capillary pressure had a minor affection on the gas production in this case study. The best well location was at the upper layer because of the gravity effect. For the effects of the geo-mechanics, we observed that the rock mechanisms had impacts on the final cumulative gas production. The larger the Young's Modulus and the smaller the Poisson's Ratio, the smaller the subsidence on the seabed. Our simulation results showed that the seabed subsidence in FWC Ridge was about 1 meter during the production period.
The role of nutrient reserves for clutch formation by Northern Pintails in Alaska
Esler, Daniel N.; Grand, James B.
1994-01-01
We analyzed carcass composition of female Northern Pintails (Anas acuta) in Alaska to assess the importance of nutrient reserves for formation of first clutches (n = 85) and renests (n = 39). Habitat (tundra vs. boreal forest), hen age (yearling vs. adult), and year (1990 vs. 1991) did not affect nutrient reserve use. During formation of first clutches, Northern Pintail hens relied on lipid reserves more than any other duck species that has been studied. For much of the nesting season, lipid reserves were used to meet costs beyond those incurred by clutch formation. Date of initiation of rapid follicle growth was related to lipid reserve dynamics; lipid reserves at initiation and the rate of lipid use both declined through the season. Protein reserves declined slightly with commitment of protein to the clutch and with date of initiation of rapid follicle growth. Use of mineral reserves for first nests was negligible. Renesting females did not use nutrient reserves. Lipid reserve levels were positively related to the amount of lipid reserves needed to complete the clutch and clutch sizes predicted from a lipid dynamics model were consistent with known clutch sizes. Similar relationships did not exist for protein. We suggest that lipid reserve levels affect timing of nesting and proximately limit clutch size of Northern Pintails.