High-throughput screening for thermoelectric sulphides by using crystal structure features as descriptors

NASA Astrophysics Data System (ADS)

Zhang, Ruizhi; Du, Baoli; Chen, Kan; Reece, Mike; Materials Research Insititute Team

With the increasing computational power and reliable databases, high-throughput screening is playing a more and more important role in the search of new thermoelectric materials. Rather than the well established density functional theory (DFT) calculation based methods, we propose an alternative approach to screen for new TE materials: using crystal structural features as 'descriptors'. We show that a non-distorted transition metal sulphide polyhedral network can be a good descriptor for high power factor according to crystal filed theory. By using Cu/S containing compounds as an example, 1600+ Cu/S containing entries in the Inorganic Crystal Structure Database (ICSD) were screened, and of those 84 phases are identified as promising thermoelectric materials. The screening results are validated by both electronic structure calculations and experimental results from the literature. We also fabricated some new compounds to test our screening results. Another advantage of using crystal structure features as descriptors is that we can easily establish structural relationships between the identified phases. Based on this, two material design approaches are discussed: 1) High-pressure synthesis of metastable phase; 2) In-situ 2-phase composites with coherent interface. This work was supported by a Marie Curie International Incoming Fellowship of the European Community Human Potential Program.

SCREENING MODEL FOR NONAQUEOUS PHASE-LIQUID TRANSPORT IN THE VADOSE ZONE USING GREEN-AMPT AND KINEMATIC WAVE THEORY

EPA Science Inventory

In this paper, a screening model for flow of a nonaqueous phase liquid (NAPL) and associated chemical transport in the vadose zone is developed. he model is based on kinematic approximation of the governing equations for both the NAPL and a partitionable chemical constituent. he ...

Design and evaluation of a theory-based, culturally relevant outreach model for breast and cervical cancer screening for Latina immigrants.

PubMed

White, Kari; Garces, Isabel C; Bandura, Lisa; McGuire, Allison A; Scarinci, Isabel C

2012-01-01

Breast and cervical cancer are common among Latinas, but screening rates among foreign-born Latinas are relatively low. In this article we describe the design and implementation of a theory-based (PEN-3) outreach program to promote breast and cervical cancer screening to Latina immigrants, and evaluate the program's effectiveness. We used data from self-administered questionnaires completed at six annual outreach events to examine the sociodemographic characteristics of attendees and evaluate whether the program reached the priority population - foreign-born Latina immigrants with limited access to health care and screening services. To evaluate the program's effectiveness in connecting women to screening, we examined the proportion and characteristics of women who scheduled and attended Pap smear and mammography appointments. Among the 782 Latinas who attended the outreach program, 60% and 83% had not had a Pap smear or mammogram, respectively, in at least a year. Overall, 80% scheduled a Pap smear and 78% scheduled a mammogram. Women without insurance, who did not know where to get screening and had not been screened in the last year were more likely to schedule appointments (P < .05). Among women who scheduled appointments, 65% attended their Pap smear and 79% attended the mammogram. We did not identify significant differences in sociodemographic characteristics associated with appointment attendance. Using a theoretical approach to outreach design and implementation, it is possible to reach a substantial number of Latina immigrants and connect them to cancer screening services.

Theory in Practice: Helping Providers Address Depression in Diabetes Care

ERIC Educational Resources Information Center

Osborn, Chandra Y.; Kozak, Cindy; Wagner, Julie

2010-01-01

Introduction: A continuing education (CE) program based on the theory of planned behavior was designed to understand and improve health care providers' practice patterns in screening, assessing, and treating and/or referring patients with diabetes for depression treatment. Methods: Participants completed assessments of attitudes, confidence,…

Intention to undergo colonoscopy screening among relatives of colorectal cancer cases: a theory-based model.

PubMed

Boonyasiriwat, Watcharaporn; Hung, Man; Hon, Shirley D; Tang, Philip; Pappas, Lisa M; Burt, Randall W; Schwartz, Marc D; Stroup, Antoinette M; Kinney, Anita Y

2014-06-01

It is recommended that persons having familial risk of colorectal cancer begin regular colonoscopy screening at an earlier age than those in the general population. However, many individuals at increased risk do not adhere to these screening recommendations. The goal of this study was to examine cognitive, affective, social, and behavioral motivators of colonoscopy intention among individuals at increased risk of familial colorectal cancer. Relatives of colorectal cancer cases (N = 481) eligible for colonoscopy screening completed a survey assessing constructs from several theoretical frameworks including fear appeal theories. Structural equation modeling indicated that perceived colorectal cancer risk, past colonoscopy, fear of colorectal cancer, support from family and friends, and health-care provider recommendation were determinants of colonoscopy intention. Future interventions to promote colonoscopy in this increased risk population should target the factors we identified as motivators. (ClinicalTrials.gov number NCT01274143).

A Quantum-Based Similarity Method in Virtual Screening.

PubMed

Al-Dabbagh, Mohammed Mumtaz; Salim, Naomie; Himmat, Mubarak; Ahmed, Ali; Saeed, Faisal

2015-10-02

One of the most widely-used techniques for ligand-based virtual screening is similarity searching. This study adopted the concepts of quantum mechanics to present as state-of-the-art similarity method of molecules inspired from quantum theory. The representation of molecular compounds in mathematical quantum space plays a vital role in the development of quantum-based similarity approach. One of the key concepts of quantum theory is the use of complex numbers. Hence, this study proposed three various techniques to embed and to re-represent the molecular compounds to correspond with complex numbers format. The quantum-based similarity method that developed in this study depending on complex pure Hilbert space of molecules called Standard Quantum-Based (SQB). The recall of retrieved active molecules were at top 1% and top 5%, and significant test is used to evaluate our proposed methods. The MDL drug data report (MDDR), maximum unbiased validation (MUV) and Directory of Useful Decoys (DUD) data sets were used for experiments and were represented by 2D fingerprints. Simulated virtual screening experiment show that the effectiveness of SQB method was significantly increased due to the role of representational power of molecular compounds in complex numbers forms compared to Tanimoto benchmark similarity measure.

A pilot randomized, controlled trial of an active video game physical activity intervention.

PubMed

Peng, Wei; Pfeiffer, Karin A; Winn, Brian; Lin, Jih-Hsuan; Suton, Darijan

2015-12-01

Active video games (AVGs) transform the sedentary screen time of video gaming into active screen time and have great potential to serve as a "gateway" tool to a more active lifestyle for the least active individuals. This pilot randomized trial was conducted to explore the potential of theory-guided active video games in increasing moderate-to-vigorous physical activity (MVPA) among young adults. In this pilot 4-week intervention, participants were randomly assigned to 1 of the following groups: an AVG group with all the self determination theory (SDT)-based game features turned off, an AVG group with all the SDT-based game features turned on, a passive gameplay group with all the SDT-based game features turned on, and a control group. Physical activity was measured using ActiGraph GT3X accelerometers. Other outcomes included attendance and perceived need satisfaction of autonomy, competence and relatedness. It was found that playing the self-determination theory supported AVG resulted in greater MVPA compared with the control group immediately postintervention. The AVG with the theory-supported features also resulted in greater attendance and psychological need satisfaction than the non-theory-supported one. An AVG designed with motivation theory informed features positively impacted attendance and MVPA immediately postintervention, suggesting that including AVG features guided with motivation theory may be a method of addressing common problems with adherence and increasing effectiveness of active gaming. (PsycINFO Database Record (c) 2015 APA, all rights reserved).

SCREENING MODEL FOR NONAQUEOUS PHASE LIQUID TRANS- PORT IN THE VADOSE ZONE USING GREEN-AMPT AND KINEMATIC WAVE THEORY

EPA Science Inventory

In this paper, a screening model for flow of a nonaqueous phase liquid (NAPL) and associated chemical transport in the vadose zone is developed. The model is based on kinematic approximation of the governing equations for both the NAPL and a partitionable chemical constituent. Th...

Improving uptake of flexible sigmoidoscopy screening: a randomized trial of nonparticipant reminders in the English Screening Programme.

PubMed

Kerrison, Robert S; McGregor, Lesley M; Marshall, Sarah; Isitt, John; Counsell, Nicholas; Rees, Colin J; von Wagner, Christian

2017-01-01

Background and study aims  Uptake of flexible sigmoidoscopy screening in the English Bowel Scope Screening (BSS) Programme is low. The aim of this study was to test the impact of a nonparticipant reminder and theory-based leaflet to promote uptake among former nonresponders (previously did not confirm their appointment) and nonattenders (previously confirmed their appointment but did not attend). Patients and methods  Eligible adults were men and women in London who had not attended a BSS appointment within 12 months of their invitation. Individuals were randomized (1:1:1) to receive no reminder (control), a 12-month reminder plus standard information booklet (TMR-SIB), or a 12-month reminder plus bespoke theory-based leaflet (TMR-TBL) designed to address barriers to screening. The primary outcome of the study was the proportion of individuals screened within each group 12 weeks after the delivery of the reminder. Results  A total of 1383 men and women were randomized and analyzed as allocated (n = 461 per trial arm). Uptake was 0.2 % (n = 1), 10.4 % (n = 48), and 15.2 % (n = 70) in the control, TMR-SIB, and TMR-TBL groups, respectively. Individuals in the TMR-SIB and TMR-TBL groups were significantly more likely to attend screening than individuals in the control group (adjusted odds ratio [OR] 53.7, 95 % confidence interval [CI] 7.4 - 391.4, P  < 0.001 and OR 89.0, 95 %CIs 12.3 - 645.4, P  < 0.01, respectively). Individuals in the TMR-TBL group were also significantly more likely to attend screening than individuals in the TMR-SIB group (OR 1.7, 95 %CIs 1.1 - 2.5, P  = 0.01). Across all groups, former nonattenders were more likely to participate in screening than former nonresponders (uptake was 14.2 % and 8.0 %, respectively; OR 2.5, 95 %CIs 1.4 - 4.4, P  < 0.01). The adenoma detection rate among screened adults was 7.6 %, which is comparable to the rate in initial attenders. Conclusions  Reminders targeting former nonparticipants can improve uptake and are effective for both former nonresponders and nonattenders. Theory-based information designed to target barriers to screening added significantly to this strategy. © Georg Thieme Verlag KG Stuttgart · New York.

Perceived Susceptibility to Illness and Perceived Benefits of Preventive Care: An Exploration of Behavioral Theory Constructs in a Transcultural Context

PubMed Central

Joseph, Galen; Burke, Nancy J.; Tuason, Noe; Barker, Judith C.; Pasick, Rena J.

2010-01-01

This article describes how the social context of transculturation (cultural change processes) and transmigration (migration in which relationships are sustained across national boundaries) can directly influence use of mammography screening. The authors conducted semistructured interviews with Latino and Filipino academics and social service providers and with U.S.-born and immigrant Latinas and Filipinas to explore direct and indirect influences of social context on health behavior (Behavioral Constructs and Culture in Cancer Screening study). Iterative analyses identified themes of the transcultural domain: colonialism, immigration, discrimination, and therapeutic engagement. In this domain, the authors examine two key behavioral theory constructs, perceptions of susceptibility to illness and perceptions of benefits of preventive medical care. The findings raise concerns about interventions to promote mammography screening primarily based on provision of scientific information. The authors conclude that social context affects behavior directly rather than exclusively through beliefs as behavioral theory implies and that understanding contextual influences, such as transculturation, points to different forms of intervention. PMID:19805792

Design and evaluation of a theory-based, culturally relevant outreach model for breast and cervical cancer screening for Latina immigrants

PubMed Central

White, Kari; Garces, Isabel C.; Bandura, Lisa; McGuire, Allison A.; Scarinci, Isabel C.

2013-01-01

Objectives Breast and cervical cancer are common among Latinas, but screening rates among foreign-born Latinas are relatively low. In this article we describe the design and implementation of a theory-based (PEN-3) outreach program to promote breast and cervical cancer screening to Latina immigrants, and evaluate the program’s effectiveness. Methods We used data from self-administered questionnaires completed at six annual outreach events to examine the sociodemographic characteristics of attendees and evaluate whether the program reached the priority population – foreign-born Latina immigrants with limited access to health care and screening services. To evaluate the program’s effectiveness in connecting women to screening, we examined the proportion and characteristics of women who scheduled and attended Pap smear and mammography appointments. Results Among the 782 Latinas who attended the outreach program, 60% and 83% had not had a Pap smear or mammogram, respectively, in at least a year. Overall, 80% scheduled a Pap smear and 78% scheduled a mammogram. Women without insurance, who did not know where to get screening and had not been screened in the last year were more likely to schedule appointments (p < 0.05). Among women who scheduled appointments, 65% attended their Pap smear and 79% attended the mammogram. We did not identify significant differences in sociodemographic characteristics associated with appointment attendance. Conclusions Using a theoretical approach to outreach design and implementation, it is possible to reach a substantial number of Latina immigrants and connect them to cancer screening services. PMID:22870569

Preconceptions influence women's perceptions of information on breast cancer screening: a qualitative study.

PubMed

Henriksen, Mikael Johannes Vuokko; Guassora, Ann Dorrit; Brodersen, John

2015-09-03

Screening for breast cancer has been subject to intense debate in recent decades regarding benefits and risks. Participation in breast cancer screening should be based on informed choice, and most countries approach this by sending information leaflets with invitations to attend screening. However, very little attention has been paid to the decision-making process and how the information leaflets are used and understood by women. The aim of this study is twofold. First, we use a theoretical framework to explore how the framing of information influences the intention to participate in breast cancer screening. Second, we discuss how information and attitudes held prior to receiving the invitation influence the perception of the balance between the benefits and risks harms of screening. We used a qualitative design and interviewed six women who were soon to receive their first invitation to participate in the breast screening programme in Denmark. The selected women received a copy of the official information leaflet 1 week before we interviewed them. The six women were interviewed individually using an interview guide based on the theory of planned behaviour. We used meaning condensation for our initial analysis, and further analysis was guided by the theory of cognitive dissonance. For our participants, the decision-making process was dominated by the attitudes of the women's circle of acquaintances and, to a lesser extent, by the information that accompanied the screening invitation. Information that conflicted with attitudes the women already held was actively disregarded. The risk of overdiagnosis as a potentially harmful effect of participation in mammography screening was unknown to the women in our study. An isolated framing effect was not found. Women have expectations about breast cancer screening that are formed before they receive information from the screening programme. These expectations compromise the perception of balance between screening benefits and potential harmful effects. They also influence the perception of the information in the breast screening leaflet. The phenomenon of overdiagnosis is unknown to the women.

Renormalization group method based on the ionization energy theory

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

Arulsamy, Andrew Das, E-mail: sadwerdna@gmail.com; School of Physics, University of Sydney, Sydney, New South Wales 2006

2011-03-15

Proofs are developed to explicitly show that the ionization energy theory is a renormalized theory, which mathematically exactly satisfies the renormalization group formalisms developed by Gell-Mann-Low, Shankar and Zinn-Justin. However, the cutoff parameter for the ionization energy theory relies on the energy-level spacing, instead of lattice point spacing in k-space. Subsequently, we apply the earlier proofs to prove that the mathematical structure of the ionization-energy dressed electron-electron screened Coulomb potential is exactly the same as the ionization-energy dressed electron-phonon interaction potential. The latter proof is proven by means of the second-order time-independent perturbation theory with the heavier effective mass condition,more » as required by the electron-electron screened Coulomb potential. The outcome of this proof is that we can derive the heat capacity and the Debye frequency as a function of ionization energy, which can be applied in strongly correlated matter and nanostructures.« less

How well do the theory of reasoned action and theory of planned behaviour predict intentions and attendance at screening programmes? A meta-analysis.

PubMed

Cooke, Richard; French, David P

2008-01-01

Meta-analysis was used to quantify how well the Theories of Reasoned Action and Planned Behaviour have predicted intentions to attend screening programmes and actual attendance behaviour. Systematic literature searches identified 33 studies that were included in the review. Across the studies as a whole, attitudes had a large-sized relationship with intention, while subjective norms and perceived behavioural control (PBC) possessed medium-sized relationships with intention. Intention had a medium-sized relationship with attendance, whereas the PBC-attendance relationship was small sized. Due to heterogeneity in results between studies, moderator analyses were conducted. The moderator variables were (a) type of screening test, (b) location of recruitment, (c) screening cost and (d) invitation to screen. All moderators affected theory of planned behaviour relationships. Suggestions for future research emerging from these results include targeting attitudes to promote intention to screen, a greater use of implementation intentions in screening information and examining the credibility of different screening providers.

Multimedia Learning in an Interactive Self-Explaining Environment: What Works in the Design of Agent-Based Microworlds?

ERIC Educational Resources Information Center

Mayer, Richard E.; Dow, Gayle T.; Mayer, Sarah

2003-01-01

Students learned about electric motors by asking questions and receiving answers from an on-screen pedagogical agent named Dr. Phyz who stood next to an on-screen drawing of an electric motor. Results are consistent with a cognitive theory of multimedia learning and yield principles for the design of interactive multimedia learning environments.…

Selection Metric for Photovoltaic Materials Screening Based on Detailed-Balance Analysis

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

Blank, Beatrix; Kirchartz, Thomas; Lany, Stephan

The success of recently discovered absorber materials for photovoltaic applications has been generating increasing interest in systematic materials screening over the last years. However, the key for a successful materials screening is a suitable selection metric that goes beyond the Shockley-Queisser theory that determines the thermodynamic efficiency limit of an absorber material solely by its band-gap energy. Here, we develop a selection metric to quantify the potential photovoltaic efficiency of a material. Our approach is compatible with detailed balance and applicable in computational and experimental materials screening. We use the complex refractive index to calculate radiative and nonradiative efficiency limitsmore » and the respective optimal thickness in the high mobility limit. We also compare our model to the widely applied selection metric by Yu and Zunger [Phys. Rev. Lett. 108, 068701 (2012)] with respect to their dependence on thickness, internal luminescence quantum efficiency, and refractive index. Finally, the model is applied to complex refractive indices calculated via electronic structure theory.« less

Selection Metric for Photovoltaic Materials Screening Based on Detailed-Balance Analysis

DOE PAGES

Blank, Beatrix; Kirchartz, Thomas; Lany, Stephan; ...

2017-08-31

The success of recently discovered absorber materials for photovoltaic applications has been generating increasing interest in systematic materials screening over the last years. However, the key for a successful materials screening is a suitable selection metric that goes beyond the Shockley-Queisser theory that determines the thermodynamic efficiency limit of an absorber material solely by its band-gap energy. Here, we develop a selection metric to quantify the potential photovoltaic efficiency of a material. Our approach is compatible with detailed balance and applicable in computational and experimental materials screening. We use the complex refractive index to calculate radiative and nonradiative efficiency limitsmore » and the respective optimal thickness in the high mobility limit. We also compare our model to the widely applied selection metric by Yu and Zunger [Phys. Rev. Lett. 108, 068701 (2012)] with respect to their dependence on thickness, internal luminescence quantum efficiency, and refractive index. Finally, the model is applied to complex refractive indices calculated via electronic structure theory.« less

Targeting and tailoring message-framing: the moderating effect of racial identity on receptivity to colorectal cancer screening among African-Americans.

PubMed

Lucas, Todd; Manning, Mark; Hayman, Lenwood W; Blessman, James

2018-06-07

This study demonstrates the potential of racial identity to moderate how gain and loss-framed messaging, as well as culturally-targeted messaging, can affect receptivity to preventive health screening. African-Americans (N = 132) who were noncompliant with recommended colorectal cancer (CRC) screening completed a measure of racial identity centrality-encompassing the extent to which racial identity is a core component of self-concept-and then participated in an online education module about CRC screening, during which either gain or loss-framed messaging was introduced. Half of African-Americans were also exposed to a culturally-targeted self-help message about preventing CRC. Theory of Planned Behavior measures of attitudes, normative beliefs, perceived behavioral control, and intentions to obtain a CRC screen served as outcomes. Results confirmed that effects of messaging on receptivity to CRC screening depended on racial identity. Among low racial identity African Americans, gain-framed messaging most effectively increased normative beliefs about obtaining CRC screening, whereas among high racial identity African Americans loss-framed messaging was most compelling. However, these effects most strongly emerged when culturally-targeted self-help messaging was included. We discuss implications for health disparities theory and research, including a potential to simultaneously deploy culturally-targeted and tailored messaging based on racial identity.

Characteristics of white LED transmission through a smoke screen

NASA Astrophysics Data System (ADS)

Zheng, Yunfei; Yang, Aiying; Feng, Lihui; Guo, Peng

2018-01-01

The characteristics of white LED transmission through a smoke screen is critical for visible light communication through a smoke screen. Based on the Mie scattering theory, the Monte Carlo transmission model is established. Based on the probability density function, the white LED sampling model is established according to the measured spectrum of a white LED and the distribution angle of the lambert model. The sampling model of smoke screen particle diameter is also established according to its distribution. We simulate numerically the influence the smoke thickness, the smoke concentration and the angle of irradiance of white LED on transmittance of the white LED. We construct a white LED smoke transmission experiment system. The measured result on the light transmittance and the smoke concentration agreed with the simulated result, and demonstrated the validity of simulation model for visible light transmission channel through a smoke screen.

Socio-Cognitive Determinants of the Mammography Screening Uptake among Iranian Women

PubMed

Mirzaei-Alavijeh, Mehdi; Ghorbani, Parvaneh; Jalilian, Farzad

2018-05-26

Background: Mammography screening uptake is the most effective method in breast cancer screening. The aim of this study was to determine the determinants related to mammography screening uptake among Iranian women based on the theory of planned behavior. Materials and Methods: This cross-sectional study was conducted among 408 women who referred to health centers in Kermanshah city, the western of Iran, during 2016. Participants filled out a self-administered questionnaire. Data were analyzed by SPSS version 21 using Pearson correlation, linear and logistic regression statistical tests at 95% significant level. Results: The mean age of participants was 39.61 years [SD: 8.28], ranged from 30 to 60 years. Almost 13% of the participants had already mammography screening uptake at least once. Perceived behavioral control (OR=1.229) and behavioral intention (OR=1.283) were the more influential predictors on mammography screening uptake. Conclusions: Based on result, it seems increase perceived behavior control toward mammography screening uptake may be usefulness in promotion of mammography screening uptake among Iranian women. Creative Commons Attribution License

Effects of education based on the health belief model on screening behavior in high risk women for breast cancer, Tehran, Iran.

PubMed

Hajian, Sepideh; Vakilian, Katayon; Najabadi, Khadijeh Mirzaii; Hosseini, Jalil; Mirzaei, Hamid Reza

2011-01-01

Breast cancer is the most common malignancy in women. Early diagnosis allows efficient treatment and increases survival, but the efficacy of breast self examination (BSE) is not sufficiently well established. The American Cancer Society aims to give women the opportunity to recognize the utility, limitations and adverse effects of breast cancer screening through education models based on psychological theories. With the Health Belief Model, people's health perceptions and attitudes influence their practices, for example with screening. The purpose of this randomized controlled clinical trial was to determine the effect of education based on this model on breast cancer screening in high risk Iranian women. Participants were women with a family history of breast cancer (mother, sister, and daughter). After explanation of the study objectives to participants, they were recruited on obtaining oral consent and each filled out the study questionnaire based on the Health Belief Model. Allocation was into two groups by computerized randomization, control and intervention, receiving education on breast cancer screening. Perceived susceptibility to and seriousness of breast cancer, perceived usefulness of and barriers to BSE, clinical breast examination, and mammography, and self-efficacy in the ability to perform these, were assessed, with comparison of scores for BSE practice before and after education and doing mammography and clinical examination by a physician in intervention and control group. The mean age was 37.8 ± 11.7 (range 19-60). The mean rank in the intervention group significantly differed before and after the education, but except for " perceived threat" and "perceived usefulness of breast self examination", we did not find any significant differences from the control group. After educational sessions, breast self examination and clinical examination practice rates were elevated. Health education based on well known psychological theories for breast cancer screening should be extended to the entire populations in developing countries. In addition, we should pay attention to barriers to women undergoing mammography, such as costs, shame and accessibility, and increase the target population awareness and positive attitudes towards benefits of early breast cancer screening.

Protection motivation theory in predicting intention to receive cervical cancer screening in rural Chinese women.

PubMed

Bai, Yang; Liu, Qing; Chen, Xinguang; Gao, Yanduo; Gong, Huiyun; Tan, Xiaodong; Zhang, Min; Tuo, Jiyu; Zhang, Yuling; Xiang, Qunying; Deng, Fenghua; Liu, Guiling

2018-02-01

Despite the significance of cervical cancer screening, motivating more women to participate remains a challenge in resource-limited settings. In this study, we tested the protection motivation theory (PMT) in predicting screening intentions. Participants were women from Wufeng, a typical rural county in China. Participants (n = 3000) with no cervical cancer history were recruited from 10 randomly selected villages. As mediating variables, 6 PMT constructs (Perceived Risk, Fear Arousal, Perceived Severity, Response Efficacy, Response Cost, and Self-Efficacy) were measured using the standardized questionnaire. Structural equation modeling (SEM) method was employed to test PMT-based prediction models. Of the total sample, 57.77% believed that regular screening may reduce cervical cancer risk, and 45.26% agreed that women should be screened regularly. Our data fit the PMT model well (GFI = 0.95, AGFI = 0.93, CFI = 0.90, RMSEA = 0.06, SRMR = 0.04, Chi-square/df = 2.47). Knowledge of screening was directly and positively associated with screening intention. Age, annual income, and awareness of and prior experience with screening were significantly associated with screening intention by enhancing cervical cancer risk perception and by reducing response cost (P<0.05 for both). PMT can be used as guidance to investigate cervical cancer screening intentions among rural women in China with focus on cancer knowledge, some demographic factors, and awareness of and previous experience with screening. These findings, if verified with longitudinal data, can be used for intervention program development. Copyright © 2017 John Wiley & Sons, Ltd.

Transitioning NWChem to the Next Generation of Manycore Machines

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

Bylaska, Eric J.; Apra, E; Kowalski, Karol

The NorthWest chemistry (NWChem) modeling software is a popular molecular chemistry simulation software that was designed from the start to work on massively parallel processing supercomputers [1-3]. It contains an umbrella of modules that today includes self-consistent eld (SCF), second order Møller-Plesset perturbation theory (MP2), coupled cluster (CC), multiconguration self-consistent eld (MCSCF), selected conguration interaction (CI), tensor contraction engine (TCE) many body methods, density functional theory (DFT), time-dependent density functional theory (TDDFT), real-time time-dependent density functional theory, pseudopotential plane-wave density functional theory (PSPW), band structure (BAND), ab initio molecular dynamics (AIMD), Car-Parrinello molecular dynamics (MD), classical MD, hybrid quantum mechanicsmore » molecular mechanics (QM/MM), hybrid ab initio molecular dynamics molecular mechanics (AIMD/MM), gauge independent atomic orbital nuclear magnetic resonance (GIAO NMR), conductor like screening solvation model (COSMO), conductor-like screening solvation model based on density (COSMO-SMD), and reference interaction site model (RISM) solvation models, free energy simulations, reaction path optimization, parallel in time, among other capabilities [4]. Moreover, new capabilities continue to be added with each new release.« less

Virtual Screening with AutoDock: Theory and Practice

PubMed Central

Cosconati, Sandro; Forli, Stefano; Perryman, Alex L.; Harris, Rodney; Goodsell, David S.; Olson, Arthur J.

2011-01-01

Importance to the field Virtual screening is a computer-based technique for identifying promising compounds to bind to a target molecule of known structure. Given the rapidly increasing number of protein and nucleic acid structures, virtual screening continues to grow as an effective method for the discovery of new inhibitors and drug molecules. Areas covered in this review We describe virtual screening methods that are available in the AutoDock suite of programs, and several of our successes in using AutoDock virtual screening in pharmaceutical lead discovery. What the reader will gain A general overview of the challenges of virtual screening is presented, along with the tools available in the AutoDock suite of programs for addressing these challenges. Take home message Virtual screening is an effective tool for the discovery of compounds for use as leads in drug discovery, and the free, open source program AutoDock is an effective tool for virtual screening. PMID:21532931

Vainshtein screening in scalar-tensor theories before and after GW170817: Constraints on theories beyond Horndeski

NASA Astrophysics Data System (ADS)

Dima, Alexandru; Vernizzi, Filippo

2018-05-01

Screening mechanisms are essential features of dark energy models mediating a fifth force on large scales. We study the regime of strong scalar field nonlinearities, known as Vainshtein screening, in the most general scalar-tensor theories propagating a single scalar degree of freedom. We first develop an effective approach to parametrize cosmological perturbations beyond linear order for these theories. In the quasistatic limit, the fully nonlinear effective Lagrangian contains six independent terms, one of which starts at cubic order in perturbations. We compute the two gravitational potentials around a spherical body. Outside and near the body, screening reproduces standard gravity, with a modified gravitational coupling. Inside the body, the two potentials are different and depend on the density profile, signalling the breaking of the Vainshtein screening. We provide the most general expressions for these modifications, revising and extending previous results. We apply our findings to show that the combination of the GW170817 event, the Hulse-Taylor pulsar and stellar structure physics, constrain the parameters of these general theories at the level of 10-1, and of Gleyzes-Langlois-Piazza-Vernizzi theories at the level of 10-2.

Density functional theory based screening of ternary alkali-transition metal borohydrides: A computational material design project

NASA Astrophysics Data System (ADS)

Hummelshøj, J. S.; Landis, D. D.; Voss, J.; Jiang, T.; Tekin, A.; Bork, N.; Dułak, M.; Mortensen, J. J.; Adamska, L.; Andersin, J.; Baran, J. D.; Barmparis, G. D.; Bell, F.; Bezanilla, A. L.; Bjork, J.; Björketun, M. E.; Bleken, F.; Buchter, F.; Bürkle, M.; Burton, P. D.; Buus, B. B.; Calborean, A.; Calle-Vallejo, F.; Casolo, S.; Chandler, B. D.; Chi, D. H.; Czekaj, I.; Datta, S.; Datye, A.; DeLaRiva, A.; Despoja, V.; Dobrin, S.; Engelund, M.; Ferrighi, L.; Frondelius, P.; Fu, Q.; Fuentes, A.; Fürst, J.; García-Fuente, A.; Gavnholt, J.; Goeke, R.; Gudmundsdottir, S.; Hammond, K. D.; Hansen, H. A.; Hibbitts, D.; Hobi, E.; Howalt, J. G.; Hruby, S. L.; Huth, A.; Isaeva, L.; Jelic, J.; Jensen, I. J. T.; Kacprzak, K. A.; Kelkkanen, A.; Kelsey, D.; Kesanakurthi, D. S.; Kleis, J.; Klüpfel, P. J.; Konstantinov, I.; Korytar, R.; Koskinen, P.; Krishna, C.; Kunkes, E.; Larsen, A. H.; Lastra, J. M. G.; Lin, H.; Lopez-Acevedo, O.; Mantega, M.; Martínez, J. I.; Mesa, I. N.; Mowbray, D. J.; Mýrdal, J. S. G.; Natanzon, Y.; Nistor, A.; Olsen, T.; Park, H.; Pedroza, L. S.; Petzold, V.; Plaisance, C.; Rasmussen, J. A.; Ren, H.; Rizzi, M.; Ronco, A. S.; Rostgaard, C.; Saadi, S.; Salguero, L. A.; Santos, E. J. G.; Schoenhalz, A. L.; Shen, J.; Smedemand, M.; Stausholm-Møller, O. J.; Stibius, M.; Strange, M.; Su, H. B.; Temel, B.; Toftelund, A.; Tripkovic, V.; Vanin, M.; Viswanathan, V.; Vojvodic, A.; Wang, S.; Wellendorff, J.; Thygesen, K. S.; Rossmeisl, J.; Bligaard, T.; Jacobsen, K. W.; Nørskov, J. K.; Vegge, T.

2009-07-01

We present a computational screening study of ternary metal borohydrides for reversible hydrogen storage based on density functional theory. We investigate the stability and decomposition of alloys containing 1 alkali metal atom, Li, Na, or K (M1); and 1 alkali, alkaline earth or 3d/4d transition metal atom (M2) plus two to five (BH4)- groups, i.e., M1M2(BH4)2-5, using a number of model structures with trigonal, tetrahedral, octahedral, and free coordination of the metal borohydride complexes. Of the over 700 investigated structures, about 20 were predicted to form potentially stable alloys with promising decomposition energies. The M1(Al/Mn/Fe)(BH4)4, (Li/Na)Zn(BH4)3, and (Na/K)(Ni/Co)(BH4)3 alloys are found to be the most promising, followed by selected M1(Nb/Rh)(BH4)4 alloys.

Intrinsic motivation factors based on the self-determinant theory for regular breast cancer screening.

PubMed

Jung, Su Mi; Jo, Heui-Sug

2014-01-01

The purpose of this study was to identify factors of intrinsic motivation that affect regular breast cancer screening and contribute to development of a program for strategies to improve effective breast cancer screening. Subjects were residing in South Korea Gangwon-Province and were female over 40 and under 69 years of age. For the investigation, the Intrinsic Motivation Inventory (IMI) was modified to the situation of cancer screening and was used to survey 905 inhabitants. Multinominal logistic regression analyses were conducted for regular breast cancer screening (RS), one-time breast cancer screening (OS) and non-breast cancer screening (NS). For statistical analysis, IBM SPSS 20.0 was utilized. The determinant factors between RS and NS were "perceived effort and choice" and "stress and strain" - internal motivations related to regular breast cancer screening. Also, determinant factors between RS and OS are "age" and "perceived effort and choice" for internal motivation related to cancer screening. To increase regular screening, strategies that address individual perceived effort and choice are recommended.

[Incidence of melanoma and changes in stage-specific incidence after implementation of skin cancer screening in Schleswig-Holstein].

PubMed

Eisemann, N; Waldmann, A; Katalinic, A

2014-01-01

A pilot project in skin cancer screening (SCREEN) was conducted in Schleswig-Holstein from July 2003 to June 2004. Although the impact of this screening on the stage-specific incidence of melanoma is of great importance for screening evaluation, it remains unknown. In theory, an effective skin cancer screening program should result in a medium-term incidence decrease of melanomas with a prognostically unfavorable stage. This is studied on a population-based level by using cancer registry data. Based on data from the Cancer Registry of Schleswig-Holstein for 1999-2009, stage-specific (T-category of the TNM-classification system) age-standardized incidence rates were calculated. After implementation of the SCREEN project, the incidence of prognostically favorable melanomas (in situ and T1) was higher than before, while the incidence of advanced melanomas (T2, T3, and for women also T4) decreased considerably. The classification of tumor stages changed during the project period, which may have contributed to an artificial decrease of the stages with a poor prognosis. Nevertheless, the results are in agreement with the observed decrease of melanoma mortality in the screening region.

From facts to arguments: A study of the 2014 Swiss controversy over systematic mammography screening.

PubMed

Perrenoud, Caroline; Stiefel, Friedrich; Bourquin, Céline

2018-06-01

The Swiss Medical Board (SMB) has recently revived the controversy over mammography screening by recommending to stop the introduction of new systematic mammography screening programs. This study aimed to examine the Swiss media coverage of the release of the SMB report. The dataset consisted of 25 newspaper and "medical magazine" articles, and TV/radio interviews. The analytic approach was based on argumentation theory. Authority and community arguments were the most frequent types of arguments. With respect to authority arguments, stakeholders for instance challenged or supported the expertise of the SMB by referring to the competence of external figures of authority. Community arguments were based on common values such as life (saved thanks to systematic mammography screening) and money (costs associated with unnecessary care induced by systematic mammography screening). The efficiency of mammography screening which was the key issue of the debate appeared to be largely eluded, and the question of what women should do endures. While interpersonal and interprofessional communication has become a major topic of interest in the medical community, it appears that media communication on mammography screening is still rather ineffective. We call in particular for a more fact-based discussion. Copyright © 2017 Elsevier B.V. All rights reserved.

The Role and Design of Screen Images in Software Documentation.

ERIC Educational Resources Information Center

van der Meij, Hans

2000-01-01

Discussion of learning a new computer software program focuses on how to support the joint handling of a manual, input devices, and screen display. Describes a study that examined three design styles for manuals that included screen images to reduce split-attention problems and discusses theory versus practice and cognitive load theory.…

Direct water decomposition on transition metal surfaces: Structural dependence and catalytic screening

DOE PAGES

Tsai, Charlie; Lee, Kyoungjin; Yoo, Jong Suk; ...

2016-02-16

Density functional theory calculations are used to investigate thermal water decomposition over the close-packed (111), stepped (211), and open (100) facets of transition metal surfaces. A descriptor-based approach is used to determine that the (211) facet leads to the highest possible rates. As a result, a range of 96 binary alloys were screened for their potential activity and a rate control analysis was performed to assess how the overall rate could be improved.

A breast health educational program for Chinese-American women: 3- to 12-month postintervention effect.

PubMed

Lee-Lin, Frances; Nguyen, Thuan; Pedhiwala, Nisreen; Dieckmann, Nathan; Menon, Usha

2015-01-01

To test the efficacy of a culturally targeted breast cancer screening educational program in increasing mammogram completion in Chinese-American immigrant women. Randomized controlled study. Chinese communities, Portland, Oregon. From April 2010 to September 2011, 300 women were randomized to receive a theory-based, culturally targeted breast cancer screening educational intervention (n = 147) or a mammography screening brochure published by the National Cancer Institute (n = 153). The two-part intervention consisted of group teaching with targeted, theory-based messages followed by individual counseling sessions. Mammography completion, perceived susceptibility, perceived benefits, perceived barriers, perceived cultural barriers, and demographic variables. A 2 × 3 mixed logistic model was applied to determine odds ratio of mammogram completion. Behavior changed in both groups, with a total of 170 participants (56.7%) reporting a mammogram at 12 months. The logistic model indicated increased odds of mammogram completion in the intervention compared to the control group at 3, 6, and 12 months. When controlling for marital status, age, and age moved to the United States, the intervention group was nine times more likely to complete mammograms than the control group. The culturally targeted educational program significantly increased mammogram use among Chinese immigrant women. Further testing of effectiveness in larger community settings is needed. The intervention may also serve as a foundation from which to develop education to increase cancer screening among other minority subgroups.

Addressing Risk and Reluctance at the Nexus of HIV and Anal Cancer Screening

PubMed Central

Ka‘opua, Lana Sue I.; Cassel, Kevin; Shiramizu, Bruce; Stotzer, Rebecca L.; Robles, Andrew; Kapua, Cathy; Orton, Malulani; Milne, Cris; Sesepasara, Maddalynn

2015-01-01

Anal cancer disproportionately burdens persons living with human immunodeficiency virus (PLHIV) regardless of natal sex, sexual orientation, gender expression, and ethnic identity. Culturally competent communications are recommended to address health disparities, with sociocultural relevance ensured through constituent dialogic processes. Results are presented from six provider focus groups conducted to inform the promotion/education component of a Hawai‘i-based project on anal cancer screening tools. Krueger’s focus group methodology guided discussion queries. Verbatim transcripts of digitally recorded discussions were analyzed using grounded theory and PEN-3 procedures. Adherence to an audit trail ensured analytic rigor. Grounded theory analysis detected the overall theme of risk and reluctance to anal cancer screening, characterized by anal cancer not being “on the radar” of PLHIV, conflicting attributions of the anus and anal sex, fear of sex-shaming/-blaming, and other interrelated conceptual categories. PEN-3 analysis revealed strategies for destigmatizing anal cancer, through “real talk” (proactive, candid, nonjudgmental discussion) nested in a framework of sexual health and overall well-being, with additional tailoring for relevance to Native Hawaiians/Pacific Islanders, transgender persons, and other marginalized groups. Application of strategies for health practice are specific to the Hawai‘i context, yet may offer considerations for developing strengths-based, culturally relevant screening promotion/education with diverse PLHIV in other locales. PMID:26630979

Addressing Risk and Reluctance at the Nexus of HIV and Anal Cancer Screening.

PubMed

Ka'opua, Lana Sue I; Cassel, Kevin; Shiramizu, Bruce; Stotzer, Rebecca L; Robles, Andrew; Kapua, Cathy; Orton, Malulani; Milne, Cris; Sesepasara, Maddalynn

2016-01-01

Anal cancer disproportionately burdens persons living with human immunodeficiency virus (PLHIV) regardless of natal sex, sexual orientation, gender expression, and ethnic identity. Culturally competent communications are recommended to address health disparities, with sociocultural relevance ensured through constituent dialogic processes. Results are presented from six provider focus groups conducted to inform the promotion/education component of a Hawai'i-based project on anal cancer screening tools. Krueger's focus group methodology guided discussion queries. Verbatim transcripts of digitally recorded discussions were analyzed using grounded theory and PEN-3 procedures. Adherence to an audit trail ensured analytic rigor. Grounded theory analysis detected the overall theme of risk and reluctance to anal cancer screening, characterized by anal cancer not being "on the radar" of PLHIV, conflicting attributions of the anus and anal sex, fear of sex-shaming/-blaming, and other interrelated conceptual categories. PEN-3 analysis revealed strategies for destigmatizing anal cancer, through "real talk" (proactive, candid, nonjudgmental discussion) nested in a framework of sexual health and overall well-being, with additional tailoring for relevance to Native Hawaiians/Pacific Islanders, transgender persons, and other marginalized groups. Application of strategies for health practice are specific to the Hawai'i context, yet may offer considerations for developing strengths-based, culturally relevant screening promotion/education with diverse PLHIV in other locales. © 2015 Society for Public Health Education.

Modeling Precheck Parallel Screening Process in the Face of Strategic Applicants with Incomplete Information and Screening Errors.

PubMed

Song, Cen; Zhuang, Jun

2018-01-01

In security check systems, tighter screening processes increase the security level, but also cause more congestion, which could cause longer wait times. Having to deal with more congestion in lines could also cause issues for the screeners. The Transportation Security Administration (TSA) Precheck Program was introduced to create fast lanes in airports with the goal of expediting passengers who the TSA does not deem to be threats. In this lane, the TSA allows passengers to enjoy fewer restrictions in order to speed up the screening time. Motivated by the TSA Precheck Program, we study parallel queueing imperfect screening systems, where the potential normal and adversary participants/applicants decide whether to apply to the Precheck Program or not. The approved participants would be assigned to a faster screening channel based on a screening policy determined by an approver, who balances the concerns of safety of the passengers and congestion of the lines. There exist three types of optimal normal applicant's application strategy, which depend on whether the marginal payoff is negative or positive, or whether the marginal benefit equals the marginal cost. An adversary applicant would not apply when the screening policy is sufficiently large or the number of utilized benefits is sufficiently small. The basic model is extended by considering (1) applicants' parameters to follow different distributions and (2) applicants to have risk levels, where the approver determines the threshold value needed to qualify for Precheck. This article integrates game theory and queueing theory to study the optimal screening policy and provides some insights to imperfect parallel queueing screening systems. © 2017 Society for Risk Analysis.

Development of a Colorectal Cancer Screening Intervention for Iranian Adults: Appling Intervention Mapping

PubMed

Besharati, Fereshteh; Karimi-Shahanjarini, Akram; Hazavehei, Seyed Mohammad Mehdi; Bashirian, Saeid; Bagheri, Fahimeh; Faradmal, Javad

2017-08-27

Background: While the incidence rate of the colorectal cancer (CRC) has been increasing over the last three decades in Iran, very limited interventions to increase CRC screening have been developed for Iranian population. The purpose of this study was to describe the use of Intervention Mapping (IM) for applying theory and evidence and considering local contexts to develop a CRC screening program among adults in Iran. Materials and Methods: From April 2014 to July 2016 following the IM process, six steps were formulated and implemented. First a need assessment was conducted involving relevant stakeholders and using focus groups discussions (n=10), individual interviews (n=20), and a household survey (n= 480). Then a matrix of change objectives was developed for each behavioral outcome and theoretical methods and their practical applications were identified to guide intervention development and implementation. A multi-component intervention was developed and piloted. Decision on suitable parts of intervention was made based on feedback of pilot study. Finally, evaluation plan including process and outcome evaluation was generated and conducted to inform future scale up. Results: The needs assessment highlighted factors affecting CRC screening including knowledge, self efficacy, social support and perceived benefit and barriers (financial problems, fear of detection of cancer and etc). Results of needs assessment were used to develop next steps IM. The program utilized methods like information delivery, modeling, and persuasion. Practical applications included video presentation, group discussion, role playing and postcards.This program was assessed through a cluster-randomized controlled trial. Results showed that there were significant differences in CRC screening uptake between intervention groups and control (P<0.001). Conclusions: IM is a useful process in the design of a theory-based intervention addressing CRC screening among Iranian population. Creative Commons Attribution License

Tests of gravity with future space-based experiments

NASA Astrophysics Data System (ADS)

Sakstein, Jeremy

2018-03-01

Future space-based tests of relativistic gravitation—laser ranging to Phobos, accelerometers in orbit, and optical networks surrounding Earth—will constrain the theory of gravity with unprecedented precision by testing the inverse-square law, the strong and weak equivalence principles, and the deflection and time delay of light by massive bodies. In this paper, we estimate the bounds that could be obtained on alternative gravity theories that use screening mechanisms to suppress deviations from general relativity in the Solar System: chameleon, symmetron, and Galileon models. We find that space-based tests of the parametrized post-Newtonian parameter γ will constrain chameleon and symmetron theories to new levels, and that tests of the inverse-square law using laser ranging to Phobos will provide the most stringent constraints on Galileon theories to date. We end by discussing the potential for constraining these theories using upcoming tests of the weak equivalence principle, and conclude that further theoretical modeling is required in order to fully utilize the data.

Debye screening and a Thomas - Fermi model of a dyonic atom in a two potential theory of electromagnetism

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

Wolf, C.

1993-02-01

We study the screening of a central Abelian dyon by a surrounding dyon cloud in a two potential theory of electromagnetism. A generalized formula for the Debye screening length is obtained and a Thomas - Fermi Model for a charged cloud surrounding a central Dyonic Core is studied. 20 refs.

Electronic Risk Assessment System as an Appropriate Tool for the Prevention of Cancer: a Qualitative Study.

PubMed

Javan Amoli, Amir Hossein; Maserat, Elham; Safdari, Reza; Zali, Mohammad Reza

2015-01-01

Decision making modalities for screening for many cancer conditions and different stages have become increasingly complex. Computer-based risk assessment systems facilitate scheduling and decision making and support the delivery of cancer screening services. The aim of this article was to survey electronic risk assessment system as an appropriate tool for the prevention of cancer. A qualitative design was used involving 21 face-to-face interviews. Interviewing involved asking questions and getting answers from exclusive managers of cancer screening. Of the participants 6 were female and 15 were male, and ages ranged from 32 to 78 years. The study was based on a grounded theory approach and the tool was a semi- structured interview. Researchers studied 5 dimensions, comprising electronic guideline standards of colorectal cancer screening, work flow of clinical and genetic activities, pathways of colorectal cancer screening and functionality of computer based guidelines and barriers. Electronic guideline standards of colorectal cancer screening were described in the s3 categories of content standard, telecommunications and technical standards and nomenclature and classification standards. According to the participations' views, workflow and genetic pathways of colorectal cancer screening were identified. The study demonstrated an effective role of computer-guided consultation for screening management. Electronic based systems facilitate real-time decision making during a clinical interaction. Electronic pathways have been applied for clinical and genetic decision support, workflow management, update recommendation and resource estimates. A suitable technical and clinical infrastructure is an integral part of clinical practice guidline of screening. As a conclusion, it is recommended to consider the necessity of architecture assessment and also integration standards.

Contextualising migrants' health behaviour - a qualitative study of transnational ties and their implications for participation in mammography screening.

PubMed

Lue Kessing, Linnea; Norredam, Marie; Kvernrod, Ann-Britt; Mygind, Anna; Kristiansen, Maria

2013-05-03

Lower participation rates in mammography screening are common among migrant women compared to native-born women. Explanations of these lower rates have mainly been based on behavioural theories investigating how lack of knowledge, access to services and culture influence the screening behaviour. The aim of the present study was to contextualise screening behaviour by exploring migrants' transnational ties and their influence on participation in mammography screening in Denmark. The study is based on the analysis of qualitative interviews with 29 women residing in greater Copenhagen, Denmark and born in Somalia, Turkey, India, Iran, Pakistan and Arab-speaking countries. We found that while women had knowledge about breast cancer and mammography screening, it was not prioritised. All women were embedded in transnational ties, which they struggled to retain through emotional and financial obligations, and these current struggles in their everyday life seemed to leave little room for concerns about breast cancer and therefore seemed to contribute to their lower participation in screening. The study emphasises the need to take into account the multi-layered and multi-sided factors in migrants' everyday life in order to further understand their health behaviour.

An effective method to screen sodium-based layered materials for sodium ion batteries

NASA Astrophysics Data System (ADS)

Zhang, Xu; Zhang, Zihe; Yao, Sai; Chen, An; Zhao, Xudong; Zhou, Zhen

2018-03-01

Due to the high cost and insufficient resource of lithium, sodium-ion batteries are widely investigated for large-scale applications. Typically, insertion-type materials possess better cyclic stability than alloy-type and conversion-type ones. Therefore, in this work, we proposed a facile and effective method to screen sodium-based layered materials based on Materials Project database as potential candidate insertion-type materials for sodium ion batteries. The obtained Na-based layered materials contains 38 kinds of space group, which reveals that the credibility of our screening approach would not be affected by the space group. Then, some important indexes of the representative materials, including the average voltage, volume change and sodium ion mobility, were further studied by means of density functional theory computations. Some materials with extremely low volume changes and Na diffusion barriers are promising candidates for sodium ion batteries. We believe that our classification algorithm could also be used to search for other alkali and multivalent ion-based layered materials, to accelerate the development of battery materials.

Promoting community practitioners' use of evidence-based approaches to increase breast cancer screening.

PubMed

Leeman, Jennifer; Moore, Alexis; Teal, Randall; Barrett, Nadine; Leighton, Ashely; Steckler, Allan

2013-07-01

Many women do not get mammography screenings at the intervals recommended for early detection and treatment of breast cancer. The Guide to Community Preventive Services (Community Guide) recommends a range of evidence-based strategies to improve mammography rates. However, nurses and others working in community-based settings make only limited use of these strategies. We report on a dissemination intervention that partnered the University of North Carolina with the Susan G. Komen Triangle Affiliate to disseminate Community Guide breast cancer screening strategies to community organizations. The intervention was guided by social marketing and diffusion of innovation theory and was designed to provide evidence and support via Komen's existing relationships with grantee organizations. The present study reports the findings from a formative evaluation of the intervention, which included a content analysis of 46 grant applications pre- and post intervention and focus groups with 20 grant recipients. © 2013 Wiley Periodicals, Inc.

Noncovalent Interactions of DNA Bases with Naphthalene and Graphene.

PubMed

Cho, Yeonchoo; Min, Seung Kyu; Yun, Jeonghun; Kim, Woo Youn; Tkatchenko, Alexandre; Kim, Kwang S

2013-04-09

The complexes of a DNA base bound to graphitic systems are studied. Considering naphthalene as the simplest graphitic system, DNA base-naphthalene complexes are scrutinized at high levels of ab initio theory including coupled cluster theory with singles, doubles, and perturbative triples excitations [CCSD(T)] at the complete basis set (CBS) limit. The stacked configurations are the most stable, where the CCSD(T)/CBS binding energies of guanine, adenine, thymine, and cytosine are 9.31, 8.48, 8.53, 7.30 kcal/mol, respectively. The energy components are investigated using symmetry-adapted perturbation theory based on density functional theory including the dispersion energy. We compared the CCSD(T)/CBS results with several density functional methods applicable to periodic systems. Considering accuracy and availability, the optB86b nonlocal functional and the Tkatchenko-Scheffler functional are used to study the binding energies of nucleobases on graphene. The predicted values are 18-24 kcal/mol, though many-body effects on screening and energy need to be further considered.

An Evaluation of Alternative Screening Procedures.

ERIC Educational Resources Information Center

Reid, Carol; Romanoff, Brenda; Algozzine, Bob; Udall, Ann

2000-01-01

This study compared the Problem Solving Assessment (PSA) procedure, an application based on Gardner's theory of multiple intelligences, with more traditional criteria for the identification of minority students for gifted education programs. Although positive correlations among approaches and intelligences were observed, different groups of…

Using the Theory of Planned Behavior to Understand Cervical Cancer Screening among Latinas

ERIC Educational Resources Information Center

Roncancio, Angelica M.; Ward, Kristy K.; Sanchez, Ingrid A.; Cano, Miguel A.; Byrd, Theresa L.; Vernon, Sally W.; Fernandez-Esquer, Maria Eugenia; Fernandez, Maria E.

2015-01-01

To reduce the high incidence of cervical cancer among Latinas in the United States it is important to understand factors that predict screening behavior. The aim of this study was to test the utility of theory of planned behavior in predicting cervical cancer screening among a group of Latinas. A sample of Latinas (N = 614) completed a baseline…

The development and testing of a brief ('gist-based') supplementary colorectal cancer screening information leaflet.

PubMed

Smith, Samuel G; Wolf, Michael S; Obichere, Austin; Raine, Rosalind; Wardle, Jane; von Wagner, Christian

2013-12-01

To design and user-test a 'gist-based' colorectal cancer screening information leaflet, which promotes comprehension of the screening offer. Twenty-eight individuals approaching screening age were recruited from organisations in deprived areas of England. Using a between-subjects design, we tested iterations of a newly-designed gist-based information leaflet. Participants read the leaflet and answered 8 'true' or 'false' comprehension statements. For the leaflet to be considered fit-for-purpose, all statements had to be answered correctly by at least 80% of participants in each round. Alterations were made if this threshold was not met and additional rounds of testing were undertaken. At round 1, answers to 2/8 statements did not meet the threshold. After changes, answers in round 2 did not reach the threshold for 1/8 statements. In round 3, all answers were adequate and the leaflet was deemed fit-for-purpose. Qualitative data offered solutions such as language and layout changes which led to improved comprehension of the leaflet. User-testing substantially improved the design and subsequent comprehensibility of a theory-driven gist-based colorectal cancer screening information leaflet. This leaflet will be evaluated as part of a large national randomised controlled trial designed to reduce socioeconomic inequalities in colorectal cancer screening participation. Copyright © 2013 The Authors. Published by Elsevier Ireland Ltd.. All rights reserved.

Multiloop atom interferometer measurements of chameleon dark energy in microgravity

NASA Astrophysics Data System (ADS)

Chiow, Sheng-wey; Yu, Nan

2018-02-01

Chameleon field is one of the promising candidates of dark energy scalar fields. As in all viable candidate field theories, a screening mechanism is implemented to be consistent with all existing tests of general relativity. The screening effect in the chameleon theory manifests its influence limited only to the thin outer layer of a bulk object, thus producing extra forces orders of magnitude weaker than that of the gravitational force of the bulk. For pointlike particles such as atoms, the depth of screening is larger than the size of the particle, such that the screening mechanism is ineffective and the chameleon force is fully expressed on the atomic test particles. Extra force measurements using atom interferometry are thus much more sensitive than bulk mass based measurements, and indeed have placed the most stringent constraints on the parameters characterizing chameleon field. In this paper, we present a conceptual measurement approach for chameleon force detection using atom interferometry in microgravity, in which multiloop atom interferometers exploit specially designed periodic modulation of chameleon fields. We show that major systematics of the dark energy force measurements, i.e., effects of gravitational forces and their gradients, can be suppressed below all hypothetical chameleon signals in the parameter space of interest.

Late-time cosmic acceleration: ABCD of dark energy and modified theories of gravity

NASA Astrophysics Data System (ADS)

Sami, M.; Myrzakulov, R.

2016-10-01

We briefly review the problems and prospects of the standard lore of dark energy. We have shown that scalar fields, in principle, cannot address the cosmological constant problem. Indeed, a fundamental scalar field is faced with a similar problem dubbed naturalness. In order to keep the discussion pedagogical, aimed at a wider audience, we have avoided technical complications in several places and resorted to heuristic arguments based on physical perceptions. We presented underlying ideas of modified theories based upon chameleon mechanism and Vainshtein screening. We have given a lucid illustration of recently investigated ghost-free nonlinear massive gravity. Again, we have sacrificed rigor and confined to the basic ideas that led to the formulation of the theory. The review ends with a brief discussion on the difficulties of the theory applied to cosmology.

Smart material screening machines using smart materials and controls

NASA Astrophysics Data System (ADS)

Allaei, Daryoush; Corradi, Gary; Waigand, Al

2002-07-01

The objective of this product is to address the specific need for improvements in the efficiency and effectiveness in physical separation technologies in the screening areas. Currently, the mining industry uses approximately 33 billion kW-hr per year, costing 1.65 billion dollars at 0.05 cents per kW-hr, of electrical energy for physical separations. Even though screening and size separations are not the single most energy intensive process in the mining industry, they are often the major bottleneck in the whole process. Improvements to this area offer tremendous potential in both energy savings and production improvements. Additionally, the vibrating screens used in the mining processing plants are the most costly areas from maintenance and worker health and safety point of views. The goal of this product is to reduce energy use in the screening and total processing areas. This goal is accomplished by developing an innovative screening machine based on smart materials and smart actuators, namely smart screen that uses advanced sensory system to continuously monitor the screening process and make appropriate adjustments to improve production. The theory behind the development of Smart Screen technology is based on two key technologies, namely smart actuators and smart Energy Flow ControlT (EFCT) strategies, developed initially for military applications. Smart Screen technology controls the flow of vibration energy and confines it to the screen rather than shaking much of the mass that makes up the conventional vibratory screening machine. Consequently, Smart Screens eliminates and downsizes many of the structural components associated with conventional vibratory screening machines. As a result, the surface area of the screen increases for a given envelope. This increase in usable screening surface area extends the life of the screens, reduces required maintenance by reducing the frequency of screen change-outs and improves throughput or productivity.

Environmental screening of dark matter haloes in f(R) gravity

NASA Astrophysics Data System (ADS)

Shi, Difu; Li, Baojiu; Han, Jiaxin

2017-07-01

In certain theories of modified gravity, Solar system constraints on deviations from general relativity (GR) are satisfied by virtue of a so-called screening mechanism, which enables the theory to revert to GR in regions where the matter density is high or the gravitational potential is deep. In the case of chameleon theories, the screening has two contributions - self-screening, which is due to the mass of an object itself, and environmental screening, which is caused by the surrounding matter - which are often entangled, with the second contribution being more crucial for less massive objects. A quantitative understanding of the effect of the environment on the screening can prove critical in observational tests of such theories using systems such as the Local Group and dwarf galaxies, for which the environment may be inferred in various ways. We use the high-resolution liminality simulation of Shi et al. to test the fidelity of different definitions of environment. We find that, although the different ways to define environment in practice do not agree with one another perfectly, they can provide useful guidance, and cross checks about how well a dark matter halo is screened. In addition, the screening of subhaloes in dark matter haloes is primarily determined by the environment, with the subhalo mass playing a minor role, which means that lower resolution simulations where subhaloes are not well resolved can still be useful for understanding the modification of gravity inside subhaloes.

Development and evaluation of nursing user interface screens using multiple methods.

PubMed

Hyun, Sookyung; Johnson, Stephen B; Stetson, Peter D; Bakken, Suzanne

2009-12-01

Building upon the foundation of the Structured Narrative Electronic Health Record (EHR) model, we applied theory-based (combined Technology Acceptance Model and Task-Technology Fit Model) and user-centered methods to explore nurses' perceptions of functional requirements for an electronic nursing documentation system, design user interface screens reflective of the nurses' perspectives, and assess nurses' perceptions of the usability of the prototype user interface screens. The methods resulted in user interface screens that were perceived to be easy to use, potentially useful, and well-matched to nursing documentation tasks associated with Nursing Admission Assessment, Blood Administration, and Nursing Discharge Summary. The methods applied in this research may serve as a guide for others wishing to implement user-centered processes to develop or extend EHR systems. In addition, some of the insights obtained in this study may be informative to the development of safe and efficient user interface screens for nursing document templates in EHRs.

Influence of Parameters of a Reactive Interatomic Potential on the Properties of Saturated Hydrocarbons

DTIC Science & Technology

2017-01-01

Methodology 3 2.1 Modified Embedded-Atom Method Theory 3 2.1.1 Embedding Energy Function 3 2.1.2 Screening Factor 8 2.1.3 Modified Embedded-Atom...Simulation Methodology 2.1 Modified Embedded-Atom Method Theory In the EAM and MEAM formalisms1,2,5 the total energy of a system of atoms (Etot) is...An interatomic potential for saturated hydrocarbons using the modified embedded-atom method (MEAM), a semiempirical many-body potential based on

Increasing chlamydia screening tests in general practice: a modified Zelen prospective Cluster Randomised Controlled Trial evaluating a complex intervention based on the Theory of Planned Behaviour.

PubMed

McNulty, Cliodna A M; Hogan, Angela H; Ricketts, Ellie J; Wallace, Louise; Oliver, Isabel; Campbell, Rona; Kalwij, Sebastian; O'Connell, Elaine; Charlett, Andre

2014-05-01

To determine if a structured complex intervention increases opportunistic chlamydia screening testing of patients aged 15-24 years attending English general practitioner (GP) practices. A prospective, Cluster Randomised Controlled Trial with a modified Zelen design involving 160 practices in South West England in 2010. The intervention was based on the Theory of Planned Behaviour (TPB). It comprised of practice-based education with up to two additional contacts to increase the importance of screening to GP staff and their confidence to offer tests through skill development (including videos). Practical resources (targets, posters, invitation cards, computer reminders, newsletters including feedback) aimed to actively influence social cognitions of staff, increasing their testing intention. Data from 76 intervention and 81 control practices were analysed. In intervention practices, chlamydia screening test rates were 2.43/100 15-24-year-olds registered preintervention, 4.34 during intervention and 3.46 postintervention; controls testing rates were 2.61/100 registered patients prior intervention, 3.0 during intervention and 2.82 postintervention. During the intervention period, testing in intervention practices was 1.76 times as great (CI 1.24 to 2.48) as controls; this persisted for 9 months postintervention (1.57 times as great, CI 1.27 to 2.30). Chlamydia infections detected increased in intervention practices from 2.1/1000 registered 15-24-year-olds prior intervention to 2.5 during the intervention compared with 2.0 and 2.3/1000 in controls (Estimated Rate Ratio intervention versus controls 1.4 (CI 1.01 to 1.93). This complex intervention doubled chlamydia screening tests in fully engaged practices. The modified Zelen design gave realistic measures of practice full engagement (63%) and efficacy of this educational intervention in general practice; it should be used more often. The trial was registered on the UK Clinical Research Network Study Portfolio database. UKCRN number 9722.

Development and Validation of Cognitive Screening Instruments.

ERIC Educational Resources Information Center

Jarman, Ronald F.

The author suggests that most research on the early detection of learning disabilities is characterisized by an ineffective and a theoretical method of selecting and validating tasks. An alternative technique is proposed, based on a neurological theory of cognitive processes, whereby task analysis is a first step, with empirical analyses as…

Randomized controlled trial of storytelling compared to a personal risk tool intervention on colorectal cancer screening in low-income patients.

PubMed

Larkey, Linda K; McClain, Darya; Roe, Denise J; Hector, Richard D; Lopez, Ana Maria; Sillanpaa, Brian; Gonzalez, Julie

2015-01-01

Screening rates for colorectal cancer (CRC) lag for low-income, minority populations, contributing to poorer survival rates. A model of storytelling as culture-centric health promotion was tested for promoting CRC screening. A two-group parallel randomized controlled trial. Primary care, safety-net clinics. Low-income patients due for CRC screening, ages 50 to 75 years, speaking English or Spanish. Patients were exposed to either a video created from personal stories composited into a drama about "Papa" receiving CRC screening, or an instrument estimating level of personal cancer risk. Patients received a health care provider referral for CRC screening and were followed up for 3 months to document adherence. Behavioral factors related to the narrative model (identification and engagement) and theory of planned behavior. Main effects of the interventions on screening were tested, controlling for attrition factors, and demographic factor associations were assessed. Path analysis with model variables was used to test the direct effects and multiple mediator models. Main effects on CRC screening (roughly half stool-based tests, half colonoscopy) did not indicate significant differences (37% and 42% screened for storytelling and risk-based messages, respectively; n = 539; 33.6% male; 62% Hispanic). Factors positively associated with CRC screening included being female, Hispanic, married or living with a partner, speaking Spanish, having a primary care provider, lower income, and no health insurance. Engagement, working through positive attitudes toward the behavior, predicted CRC screening. A storytelling and a personalized risk-tool intervention achieved similar levels of screening among unscreened/underscreened, low-income patients. Factors usually associated with lower rates of screening (e.g., no insurance, being Hispanic) were related to more adherence. Both interventions' engagement factor facilitated positive attitudes about CRC screening associated with behavior change.

Determination of a Screening Metric for High Diversity DNA Libraries.

PubMed

Guido, Nicholas J; Handerson, Steven; Joseph, Elaine M; Leake, Devin; Kung, Li A

2016-01-01

The fields of antibody engineering, enzyme optimization and pathway construction rely increasingly on screening complex variant DNA libraries. These highly diverse libraries allow researchers to sample a maximized sequence space; and therefore, more rapidly identify proteins with significantly improved activity. The current state of the art in synthetic biology allows for libraries with billions of variants, pushing the limits of researchers' ability to qualify libraries for screening by measuring the traditional quality metrics of fidelity and diversity of variants. Instead, when screening variant libraries, researchers typically use a generic, and often insufficient, oversampling rate based on a common rule-of-thumb. We have developed methods to calculate a library-specific oversampling metric, based on fidelity, diversity, and representation of variants, which informs researchers, prior to screening the library, of the amount of oversampling required to ensure that the desired fraction of variant molecules will be sampled. To derive this oversampling metric, we developed a novel alignment tool to efficiently measure frequency counts of individual nucleotide variant positions using next-generation sequencing data. Next, we apply a method based on the "coupon collector" probability theory to construct a curve of upper bound estimates of the sampling size required for any desired variant coverage. The calculated oversampling metric will guide researchers to maximize their efficiency in using highly variant libraries.

Computational screening of organic polymer dielectrics for novel accelerator technologies

DOE PAGES

Pilania, Ghanshyam; Weis, Eric; Walker, Ethan M.; ...

2018-06-18

The use of infrared lasers to power accelerating dielectric structures is a developing area of research. Within this technology, the choice of the dielectric material forming the accelerating structures, such as the photonic band gap (PBG) structures, is dictated by a range of interrelated factors including their dielectric and optical properties, amenability to photo-polymerization, thermochemical stability and other target performance metrics of the particle accelerator. In this direction, electronic structure theory aided computational screening and design of dielectric materials can play a key role in identifying potential candidate materials with the targeted functionalities to guide experimental synthetic efforts. In anmore » attempt to systematically understand the role of chemistry in controlling the electronic structure and dielectric properties of organic polymeric materials, here we employ empirical screening and density functional theory (DFT) computations, as a part of our multi-step hierarchal screening strategy. Our DFT based analysis focused on the bandgap, dielectric permittivity, and frequency-dependent dielectric losses due to lattice absorption as key properties to down-select promising polymer motifs. In addition to the specific application of dielectric laser acceleration, the general methodology presented here is deemed to be valuable in the design of new insulators with an attractive combination of dielectric properties.« less

Filling-enforced nonsymmorphic Kondo semimetals in two dimensions

NASA Astrophysics Data System (ADS)

Pixley, J. H.; Lee, SungBin; Brandom, B.; Parameswaran, S. A.

2017-08-01

We study the competition between Kondo screening and frustrated magnetism on the nonsymmorphic Shastry-Sutherland Kondo lattice at a filling of two conduction electrons per unit cell. This model is known to host a set of gapless partially Kondo screened phases intermediate between the Kondo-destroyed paramagnet and the heavy Fermi liquid. Based on crystal symmetries, we argue that (i) both the paramagnet and the heavy Fermi liquid are semimetals protected by a glide symmetry; and (ii) partial Kondo screening breaks the symmetry, removing this protection and allowing the partially Kondo screened phase to be deformed into a Kondo insulator via a Lifshitz transition. We confirm these results using large-N mean-field theory and then use nonperturbative arguments to derive a generalized Luttinger sum rule constraining the phase structure of two-dimensional nonsymmorphic Kondo lattices beyond the mean-field limit.

Designing Serious Computer Games for People With Moderate and Advanced Dementia: Interdisciplinary Theory-Driven Pilot Study.

PubMed

Tziraki, Chariklia; Berenbaum, Rakel; Gross, Daniel; Abikhzer, Judith; Ben-David, Boaz M

2017-07-31

The field of serious games for people with dementia (PwD) is mostly driven by game-design principals typically applied to games created by and for younger individuals. Little has been done developing serious games to help PwD maintain cognition and to support functionality. We aimed to create a theory-based serious game for PwD, with input from a multi-disciplinary team familiar with aging, dementia, and gaming theory, as well as direct input from end users (the iterative process). Targeting enhanced self-efficacy in daily activities, the goal was to generate a game that is acceptable, accessible and engaging for PwD. The theory-driven game development was based on the following learning theories: learning in context, errorless learning, building on capacities, and acknowledging biological changes-all with the aim to boost self-efficacy. The iterative participatory process was used for game screen development with input of 34 PwD and 14 healthy community dwelling older adults, aged over 65 years. Development of game screens was informed by the bio-psychological aging related disabilities (ie, motor, visual, and perception) as well as remaining neuropsychological capacities (ie, implicit memory) of PwD. At the conclusion of the iterative development process, a prototype game with 39 screens was used for a pilot study with 24 PwD and 14 healthy community dwelling older adults. The game was played twice weekly for 10 weeks. Quantitative analysis showed that the average speed of successful screen completion was significantly longer for PwD compared with healthy older adults. Both PwD and controls showed an equivalent linear increase in the speed for task completion with practice by the third session (P<.02). Most important, the rate of improved processing speed with practice was not statistically different between PwD and controls. This may imply that some form of learning occurred for PwD at a nonsignificantly different rate than for controls. Qualitative results indicate that PwD found the game engaging and fun. Healthy older adults found the game too easy. Increase in self-reported self-efficacy was documented with PwD only. Our study demonstrated that PwD's speed improved with practice at the same rate as healthy older adults. This implies that when tasks are designed to match PwD's abilities, learning ensues. In addition, this pilot study of a serious game, designed for PwD, was accessible, acceptable, and enjoyable for end users. Games designed based on learning theories and input of end users and a multi-disciplinary team familiar with dementia and aging may have the potential of maintaining capacity and improving functionality of PwD. A larger longer study is needed to confirm our findings and evaluate the use of these games in assessing cognitive status and functionality. ©Chariklia Tziraki, Rakel Berenbaum, Daniel Gross, Judith Abikhzer, Boaz M Ben-David. Originally published in JMIR Serious Games (http://games.jmir.org), 31.07.2017.

Designing Serious Computer Games for People With Moderate and Advanced Dementia: Interdisciplinary Theory-Driven Pilot Study

PubMed Central

Gross, Daniel; Abikhzer, Judith

2017-01-01

Background The field of serious games for people with dementia (PwD) is mostly driven by game-design principals typically applied to games created by and for younger individuals. Little has been done developing serious games to help PwD maintain cognition and to support functionality. Objectives We aimed to create a theory-based serious game for PwD, with input from a multi-disciplinary team familiar with aging, dementia, and gaming theory, as well as direct input from end users (the iterative process). Targeting enhanced self-efficacy in daily activities, the goal was to generate a game that is acceptable, accessible and engaging for PwD. Methods The theory-driven game development was based on the following learning theories: learning in context, errorless learning, building on capacities, and acknowledging biological changes—all with the aim to boost self-efficacy. The iterative participatory process was used for game screen development with input of 34 PwD and 14 healthy community dwelling older adults, aged over 65 years. Development of game screens was informed by the bio-psychological aging related disabilities (ie, motor, visual, and perception) as well as remaining neuropsychological capacities (ie, implicit memory) of PwD. At the conclusion of the iterative development process, a prototype game with 39 screens was used for a pilot study with 24 PwD and 14 healthy community dwelling older adults. The game was played twice weekly for 10 weeks. Results Quantitative analysis showed that the average speed of successful screen completion was significantly longer for PwD compared with healthy older adults. Both PwD and controls showed an equivalent linear increase in the speed for task completion with practice by the third session (P<.02). Most important, the rate of improved processing speed with practice was not statistically different between PwD and controls. This may imply that some form of learning occurred for PwD at a nonsignificantly different rate than for controls. Qualitative results indicate that PwD found the game engaging and fun. Healthy older adults found the game too easy. Increase in self-reported self-efficacy was documented with PwD only. Conclusions Our study demonstrated that PwD’s speed improved with practice at the same rate as healthy older adults. This implies that when tasks are designed to match PwD’s abilities, learning ensues. In addition, this pilot study of a serious game, designed for PwD, was accessible, acceptable, and enjoyable for end users. Games designed based on learning theories and input of end users and a multi-disciplinary team familiar with dementia and aging may have the potential of maintaining capacity and improving functionality of PwD. A larger longer study is needed to confirm our findings and evaluate the use of these games in assessing cognitive status and functionality. PMID:28760730

Vertical dielectric screening of few-layer van der Waals semiconductors.

PubMed

Koo, Jahyun; Gao, Shiyuan; Lee, Hoonkyung; Yang, Li

2017-10-05

Vertical dielectric screening is a fundamental parameter of few-layer van der Waals two-dimensional (2D) semiconductors. However, unlike the widely-accepted wisdom claiming that the vertical dielectric screening is sensitive to the thickness, our first-principles calculation based on the linear response theory (within the weak field limit) reveals that this screening is independent of the thickness and, in fact, it is the same as the corresponding bulk value. This conclusion is verified in a wide range of 2D paraelectric semiconductors, covering narrow-gap ones and wide-gap ones with different crystal symmetries, providing an efficient and reliable way to calculate and predict static dielectric screening of reduced-dimensional materials. Employing this conclusion, we satisfactorily explain the tunable band gap in gated 2D semiconductors. We further propose to engineer the vertical dielectric screening by changing the interlayer distance via vertical pressure or hybrid structures. Our predicted vertical dielectric screening can substantially simplify the understanding of a wide range of measurements and it is crucial for designing 2D functional devices.

Readiness of nursing students to screen women for domestic violence.

PubMed

Ben Natan, Merav; Khater, Marva; Ighbariyea, Raeqa; Herbet, Hanin

2016-09-01

Although domestic violence against women is common in Israel and elsewhere, and though medical staff in Israel have a universal obligation to screen women for domestic violence, actual screening rates remain low. To examine which variables affect nursing students' intention to screen women for domestic violence when providing treatment, and whether the Theory of Planned Behavior (TPB) developed by Ajzen (1991) predicts this intention. This study is a quantitative cross sectional study. A large academic nursing school in central Israel. A convenience sample of 200 nursing students who had completed at least one year of studies took part in the study. Students completed a questionnaire based on the TPB. Nursing students showed high intention to screen women for domestic violence when providing treatment. Normative beliefs, subjective norms, behavioral beliefs, perceived control, and knowledge were found to affect students' intention to screen women for domestic violence. The opinion of the clinical instructor was most significant for students. The theoretical model predicted 32% of students' intention to screen women for domestic violence, with normative beliefs being the most significant variable. Copyright © 2016 Elsevier Ltd. All rights reserved.

First imagery generated by near-field real-time aperture synthesis passive millimetre wave imagers at 94 GHz and 183 GHz

NASA Astrophysics Data System (ADS)

Salmon, Neil A.; Mason, Ian; Wilkinson, Peter; Taylor, Chris; Scicluna, Peter

2010-10-01

The first passive millimetre wave (PMMW) imagery is presented from two proof-of-concept aperture synthesis demonstrators, developed to investigate the use of aperture synthesis for personnel security screening and all weather flying at 94 GHz, and satellite based earth observation at 183 GHz [1]. Emission from point noise sources and discharge tubes are used to examine the coherence on system baselines and to measure the point spread functions, making comparisons with theory. Image quality is examined using near field aperture synthesis and G-matrix calibration imaging algorithms. The radiometric sensitivity is measured using the emission from absorbers at elevated temperatures acting as extended sources and compared with theory. Capabilities of the latest Field Programmable Gate Arrays (FPGA) technologies for aperture synthesis PMMW imaging in all-weather and security screening applications are examined.

Positive Affect, Negative Affect, and Physiological Hyperarousal among Referred and Nonreferred Youths

ERIC Educational Resources Information Center

Laurent, Jeff; Joiner, Thomas E., Jr.; Catanzaro, Salvatore J.

2011-01-01

The Positive and Negative Affect Scale for Children (PANAS-C) and the Physiological Hyperarousal Scale for Children (PH-C) seem ideal measures for school mental health screenings, because they are theory based, psychometrically sound, and brief. This study provides descriptive information and preliminary cutoff scores in an effort to increase the…

A systematic review of randomised controlled trials examining the effectiveness of breast and cervical cancer screening interventions for ethnic minority women.

PubMed

Chan, Dorothy N S; So, Winnie K W

2015-10-01

To examine the effect that breast and/or cervical cancer screening programmes for ethnic minority women have on their knowledge of and beliefs about breast or cervical cancer and screening, and on their screening intentions and uptake rates. Recommendations are also made for the format and content of such programmes, based on existing evidence. A comprehensive literature search was carried out both manually and by means of five electronic databases. The findings are summarised and synthesised in narrative fashion. The ten RCTs included here were conducted among ethnic minority women in the United States or Canada, where breast or cervical cancer screening programmes have led to improvements in screening intentions, knowledge of cervical cancer and pap test uptake. The Breast Cancer Screening Belief Scale and self-reporting were the methods commonly used to measure outcomes. The shared characteristics of both countries' programmes were that they were theory- and language-based, the instruction took place in a community setting, the materials were culturally relevant, the content highlighted key messages about breast or cervical cancer and screening measures, and there were multiple intervention strategies. Breast or cervical cancer screening programmes in Western countries have demonstrated improvements in knowledge of the disease, screening intentions and pap test uptake, although evidence on the effectiveness of the interventions has been limited. The common characteristics of programmes are identified, but a comprehensive model is still needed to link these characteristics with other factors and mediators influencing outcomes. Copyright © 2015 Elsevier Ltd. All rights reserved.

Novel Approaches to Spectral Properties of Correlated Electron Materials: From Generalized Kohn-Sham Theory to Screened Exchange Dynamical Mean Field Theory

NASA Astrophysics Data System (ADS)

Delange, Pascal; Backes, Steffen; van Roekeghem, Ambroise; Pourovskii, Leonid; Jiang, Hong; Biermann, Silke

2018-04-01

The most intriguing properties of emergent materials are typically consequences of highly correlated quantum states of their electronic degrees of freedom. Describing those materials from first principles remains a challenge for modern condensed matter theory. Here, we review, apply and discuss novel approaches to spectral properties of correlated electron materials, assessing current day predictive capabilities of electronic structure calculations. In particular, we focus on the recent Screened Exchange Dynamical Mean-Field Theory scheme and its relation to generalized Kohn-Sham Theory. These concepts are illustrated on the transition metal pnictide BaCo2As2 and elemental zinc and cadmium.

Strongly screening corrections to antineutrino energy loss by β --decay of nuclides 53Fe, 54Fe, 55Fe, and 56Fe in supernova

NASA Astrophysics Data System (ADS)

Liu, Jing-Jing; Liu, Dong-Mei

2018-06-01

Based on the p-f shell-model, we discuss and calculate β--decay half-lives of neutron-rich nuclei, with a consideration of shell and pair effects, the decay energy, and the nucleon numbers. According to the linear response theory model, we study the effect of electron screening on the electron energy, beta-decay threshold energy, and the antineutrino energy loss rate by β--decay of some iron isotopes. We find that the electron screening antineutrino energy loss rates increase by about two orders of magnitude due to the shell effects and the pairing effect. Beta-decay rates with Q-value corrections due to strong electron screening are higher than those without the Q-value corrections by more than two orders of magnitude. Our conclusions may be helpful for the research on numerical simulations of the cooling of stars.

Tetragonal and collapsed-tetragonal phases of CaFe2As2 : A view from angle-resolved photoemission and dynamical mean-field theory

NASA Astrophysics Data System (ADS)

van Roekeghem, Ambroise; Richard, Pierre; Shi, Xun; Wu, Shangfei; Zeng, Lingkun; Saparov, Bayrammurad; Ohtsubo, Yoshiyuki; Qian, Tian; Sefat, Athena S.; Biermann, Silke; Ding, Hong

2016-06-01

We present a study of the tetragonal to collapsed-tetragonal transition of CaFe2As2 using angle-resolved photoemission spectroscopy and dynamical mean field theory-based electronic structure calculations. We observe that the collapsed-tetragonal phase exhibits reduced correlations and a higher coherence temperature due to the stronger Fe-As hybridization. Furthermore, a comparison of measured photoemission spectra and theoretical spectral functions shows that momentum-dependent corrections to the density functional band structure are essential for the description of low-energy quasiparticle dispersions. We introduce those using the recently proposed combined "screened exchange + dynamical mean field theory" scheme.

[Definition of ashi point from the view of linguistics].

PubMed

Jiang, Shan; Zhao, Jingsheng

2017-01-12

The definition of ashi point has not been unified yet till now. Likewise, the precise explanation on its connotation has always been an elusive question in acupuncture theory. By collecting diverse definitions on ashi point in the textbooks of Acupuncture and Moxibustion , dictionaries and term standards, several rational elements in definitions with consensus were screened. With the assistance of two important theories of cognitive linguistics, such as figure-ground theory and distance iconicity theory, the concept of ashi point was newly defined. Additiona-lly, on the base of the understanding on several similar terms such as "taking the painful site as acupoint", "responding point" and "reactive point", the semanteme analytic method was used to distinguish the difference among them so that the more profound explorations on acupuncture therapy are expounded.

First-principles simulations of doping-dependent mesoscale screening of adatoms in graphene

NASA Astrophysics Data System (ADS)

Mostofi, Arash; Corsetti, Fabiano; Wong, Dillon; Crommie, Michael; Lischner, Johannes

Adsorbed atoms and molecules play an important role in controlling and tuning the functional properties of 2D materials. Understanding and predicting this phenomenon from theory is challenging because of the need to capture both the local chemistry of the adsorbate-substrate interaction and its complex interplay with the long-range screening response of the substrate. To address this challenge, we have developed a first-principles multi-scale approach that combines linear-scaling density-functional theory, continuum screening theory and large-scale tight-binding simulations. Focussing on the case of a calcium adatom on graphene, we draw comparison between the effect of (i) non-linearity, (ii) intraband and interband transitions, and (iii) the exchange-correlation potential, thus providing insight into the relative importance of these different factors on the screening response. We also determine the charge transfer from the adatom to the graphene substrate (the key parameter used in continuum screening models), showing it to be significantly larger than previous estimates. AM and FC acknowledge support of the EPSRC under Grant EP/J015059/1, and JL under Grant EP/N005244/1.

Charge transfer optical absorption and fluorescence emission of 4-(9-acridyl)julolidine from long-range-corrected time dependent density functional theory in polarizable continuum approach.

PubMed

Kityk, A V

2014-07-15

A long-range-corrected time-dependent density functional theory (LC-TDDFT) in combination with polarizable continuum model (PCM) have been applied to study charge transfer (CT) optical absorption and fluorescence emission energies basing on parameterized LC-BLYP xc-potential. The molecule of 4-(9-acridyl)julolidine selected for this study represents typical CT donor-acceptor dye with strongly solvent dependent optical absorption and fluorescence emission spectra. The result of calculations are compared with experimental spectra reported in the literature to derive an optimal value of the model screening parameter ω. The first absorption band appears to be quite well predictable within DFT/TDDFT/PCM with the screening parameter ω to be solvent independent (ω ≈ 0.245 Bohr(-1)) whereas the fluorescence emission exhibits a strong dependence on the range separation with ω-value varying on a rising solvent polarity from about 0.225 to 0.151 Bohr(-1). Dipolar properties of the initial state participating in the electronic transition have crucial impact on the effective screening. Copyright © 2014 Elsevier B.V. All rights reserved.

Anatomy of the magnetic catalysis by renormalization-group method

NASA Astrophysics Data System (ADS)

Hattori, Koichi; Itakura, Kazunori; Ozaki, Sho

2017-12-01

We first examine the scaling argument for a renormalization-group (RG) analysis applied to a system subject to the dimensional reduction in strong magnetic fields, and discuss the fact that a four-Fermi operator of the low-energy excitations is marginal irrespective of the strength of the coupling constant in underlying theories. We then construct a scale-dependent effective four-Fermi interaction as a result of screened photon exchanges at weak coupling, and establish the RG method appropriately including the screening effect, in which the RG evolution from ultraviolet to infrared scales is separated into two stages by the screening-mass scale. Based on a precise agreement between the dynamical mass gaps obtained from the solutions of the RG and Schwinger-Dyson equations, we discuss an equivalence between these two approaches. Focusing on QED and Nambu-Jona-Lasinio model, we clarify how the properties of the interactions manifest themselves in the mass gap, and point out an importance of respecting the intrinsic energy-scale dependences in underlying theories for the determination of the mass gap. These studies are expected to be useful for a diagnosis of the magnetic catalysis in QCD.

"I'm Just Playing iPad": Comparing Prekindergarteners' and Preservice Teachers' Social Interactions While Using Tablets for Learning

ERIC Educational Resources Information Center

Moore, Holly Carrell; Adair, Jennifer Keys

2015-01-01

In this article we share descriptive findings from two qualitative, grounded theory (Glaser, 1978, 1992, 1998) studies on how two distinct groups of learners--prekindergarteners and preservice teachers in early childhood education coursework--used touch-screen tablets in their playful, discovery-based learning processes. We found similarities…

Parameterised post-Newtonian expansion in screened regions

NASA Astrophysics Data System (ADS)

McManus, Ryan; Lombriser, Lucas; Peñarrubia, Jorge

2017-12-01

The parameterised post-Newtonian (PPN) formalism has enabled stringent tests of static weak-field gravity in a theory-independent manner. Here we incorporate screening mechanisms of modified gravity theories into the framework by introducing an effective gravitational coupling and defining the PPN parameters as functions of position. To determine these functions we develop a general method for efficiently performing the post-Newtonian expansion in screened regimes. For illustration, we derive all the PPN functions for a cubic galileon and a chameleon model. We also analyse the Shapiro time delay effect for these two models and find no deviations from General Relativity insofar as the signal path and the perturbing mass reside in a screened region of space.

Contribution of Dielectric Screening to the Total Capacitance of Few-Layer Graphene Electrodes.

PubMed

Zhan, Cheng; Jiang, De-en

2016-03-03

We apply joint density functional theory (JDFT), which treats the electrode/electrolyte interface self-consistently, to an electric double-layer capacitor (EDLC) based on few-layer graphene electrodes. The JDFT approach allows us to quantify a third contribution to the total capacitance beyond quantum capacitance (CQ) and EDL capacitance (CEDL). This contribution arises from the dielectric screening of the electric field by the surface of the few-layer graphene electrode, and we therefore term it the dielectric capacitance (CDielec). We find that CDielec becomes significant in affecting the total capacitance when the number of graphene layers in the electrode is more than three. Our investigation sheds new light on the significance of the electrode dielectric screening on the capacitance of few-layer graphene electrodes.

Modifying Heathcare System Alcohol Interventions for the High-Risk Drinking Environment: Theory in Practice

ERIC Educational Resources Information Center

Croff, Julie M.; Clapp, John D.

2015-01-01

Screening, Brief Intervention, and Referral to Treatment (SBIRT) is a model program in the medical context, but it may be missing a large portion of the population with low access to healthcare services. Young adults have the lowest rates of insurance, low healthcare service utilization, and high rates of substance use. Theory driven Screening and…

A parametrisation of modified gravity on nonlinear cosmological scales

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

Lombriser, Lucas, E-mail: llo@roe.ac.uk

2016-11-01

Viable modifications of gravity on cosmological scales predominantly rely on screening mechanisms to recover Einstein's Theory of General Relativity in the Solar System, where it has been well tested. A parametrisation of the effects of such modifications in the spherical collapse model is presented here for the use of modelling the modified nonlinear cosmological structure. The formalism allows an embedding of the different screening mechanisms operating in scalar-tensor theories through large values of the gravitational potential or its first or second derivatives as well as of linear suppression effects or more general transitions between modified and Einstein gravity limits. Eachmore » screening or suppression mechanism is parametrised by a time, mass, and environment dependent screening scale, an effective modified gravitational coupling in the fully unscreened limit that can be matched to linear theory, the exponent of a power-law radial profile of the screened coupling, determined by derivatives, symmetries, and potentials in the scalar field equation, and an interpolation rate between the screened and unscreened limits. Along with generalised perturbative methods, the parametrisation may be used to formulate a nonlinear extension to the linear parametrised post-Friedmannian framework to enable generalised tests of gravity with the wealth of observations from the nonlinear cosmological regime.« less

Transformative learning theory: facilitating mammography screening in rural women.

PubMed

Purtzer, Mary Anne; Overstreet, Lindsey

2014-03-01

To use transformative learning to investigate what experiences serve as catalysts for mammography screening, the cognitive and affective responses that result from the catalyst, and how screening behavior is impacted. A descriptive qualitative study. Southeastern Wyoming. 25 low-income, rural women aged 40 years and older. Four focus group interviews. Cancer experiences triggered universal responses of fear by screeners and nonscreeners. The manner in which that fear response was interpreted was a critical factor in the facilitation of, or impedance to, screening. Dichotomous interpretations of fear responses provided the context for screening behavior. Immobilizing and isolating experiences were associated with nonscreening behavior, whereas motivation and self-efficacy were associated with screening behavior. Transformative learning theory is a useful framework from which to explain differences in mammography screening behavior. Creating opportunities that facilitate dialogue and critical reflection hold the potential to change immobilizing and isolating frames of reference in nonscreening women. To help women transcend their fear and become self-efficacious, nurses can assess how cancer and the screening experience is viewed and, if indicated, move beyond standard education and offer opportunities for dialogue and critical reflection.

Impact evaluation of Enabling Mothers to Prevent Pediatric Obesity through Web-Based Education and Reciprocal Determinism (EMPOWER) Randomized Control Trial.

PubMed

Knowlden, Adam P; Sharma, Manoj; Cottrell, Randall R; Wilson, Bradley R A; Johnson, Marcus Lee

2015-04-01

The family and home environment is an influential antecedent of childhood obesity. The purpose of this study was to pilot test The Enabling Mothers to Prevent Pediatric Obesity through Web-Based Education and Reciprocal Determinism (EMPOWER) intervention; a newly developed, theory-based, online program for prevention of childhood obesity. The two-arm, parallel group, randomized, participant-blinded trial targeted mothers with children between 4 and 6 years of age. Measures were collected at baseline, 4 weeks, and 8 weeks to evaluate programmatic effects on constructs of social cognitive theory (SCT) and obesity-related behaviors. Process evaluation transpired concurrently with each intervention session. Fifty-seven participants were randomly assigned to receive either experimental EMPOWER (n = 29) or active control Healthy Lifestyles (n = 28) intervention. Significant main effects were identified for child physical activity, sugar-free beverage consumption, and screen time, indicating that both groups improved in these behaviors. A significant group-by-time interaction was detected for child fruit and vegetable (FV) consumption as well as the SCT construct of environment in the EMPOWER cohort. An increase of 1.613 cups of FVs (95% confidence interval = [0.698, 2.529]) was found in the experimental group, relative to the active control group. Change score analysis found changes in the home environment accounted for 31.4% of the change in child FV intake for the experimental group. Child physical activity, sugar-free beverage consumption, and screen time improved in both groups over the course of the trial. Only the theory-based intervention was efficacious in increasing child FV consumption. The EMPOWER program was robust for inducing change in the home environment leading to an increase in child FV intake (Cohen's f = 0.160). © 2014 Society for Public Health Education.

Electrostatic correlations in inhomogeneous charged fluids beyond loop expansion

NASA Astrophysics Data System (ADS)

Buyukdagli, Sahin; Achim, C. V.; Ala-Nissila, T.

2012-09-01

Electrostatic correlation effects in inhomogeneous symmetric electrolytes are investigated within a previously developed electrostatic self-consistent theory [R. R. Netz and H. Orland, Eur. Phys. J. E 11, 301 (2003)], 10.1140/epje/i2002-10159-0. To this aim, we introduce two computational approaches that allow to solve the self-consistent equations beyond the loop expansion. The first method is based on a perturbative Green's function technique, and the second one is an extension of a previously introduced semiclassical approximation for single dielectric interfaces to the case of slit nanopores. Both approaches can handle the case of dielectrically discontinuous boundaries where the one-loop theory is known to fail. By comparing the theoretical results obtained from these schemes with the results of the Monte Carlo simulations that we ran for ions at neutral single dielectric interfaces, we first show that the weak coupling Debye-Huckel theory remains quantitatively accurate up to the bulk ion density ρb ≃ 0.01 M, whereas the self-consistent theory exhibits a good quantitative accuracy up to ρb ≃ 0.2 M, thus improving the accuracy of the Debye-Huckel theory by one order of magnitude in ionic strength. Furthermore, we compare the predictions of the self-consistent theory with previous Monte Carlo simulation data for charged dielectric interfaces and show that the proposed approaches can also accurately handle the correlation effects induced by the surface charge in a parameter regime where the mean-field result significantly deviates from the Monte Carlo data. Then, we derive from the perturbative self-consistent scheme the one-loop theory of asymmetrically partitioned salt systems around a dielectrically homogeneous charged surface. It is shown that correlation effects originate in these systems from a competition between the salt screening loss at the interface driving the ions to the bulk region, and the interfacial counterion screening excess attracting them towards the surface. This competition can be quantified in terms of the characteristic surface charge σ _s^*=√{2ρ _b/(π ℓ _B)}, where ℓB = 7 Å is the Bjerrum length. In the case of weak surface charges σ _s≪ σ _s^* where counterions form a diffuse layer, the interfacial salt screening loss is the dominant effect. As a result, correlation effects decrease the mean-field density of both coions and counterions. With an increase of the surface charge towards σ _s^*, the surface-attractive counterion screening excess starts to dominate, and correlation effects amplify in this regime the mean-field density of both type of ions. However, in the regime σ _s>σ _s^*, the same counterion screening excess also results in a significant decrease of the electrostatic mean-field potential. This reduces in turn the mean-field counterion density far from the charged surface. We also show that for σ _s≫ σ _s^*, electrostatic correlations result in a charge inversion effect. However, the electrostatic coupling regime where this phenomenon takes place should be verified with Monte Carlo simulations since this parameter regime is located beyond the validity range of the one-loop theory.

Electrostatic correlations in inhomogeneous charged fluids beyond loop expansion.

PubMed

Buyukdagli, Sahin; Achim, C V; Ala-Nissila, T

2012-09-14

Electrostatic correlation effects in inhomogeneous symmetric electrolytes are investigated within a previously developed electrostatic self-consistent theory [R. R. Netz and H. Orland, Eur. Phys. J. E 11, 301 (2003)]. To this aim, we introduce two computational approaches that allow to solve the self-consistent equations beyond the loop expansion. The first method is based on a perturbative Green's function technique, and the second one is an extension of a previously introduced semiclassical approximation for single dielectric interfaces to the case of slit nanopores. Both approaches can handle the case of dielectrically discontinuous boundaries where the one-loop theory is known to fail. By comparing the theoretical results obtained from these schemes with the results of the Monte Carlo simulations that we ran for ions at neutral single dielectric interfaces, we first show that the weak coupling Debye-Huckel theory remains quantitatively accurate up to the bulk ion density ρ(b) ≃ 0.01 M, whereas the self-consistent theory exhibits a good quantitative accuracy up to ρ(b) ≃ 0.2 M, thus improving the accuracy of the Debye-Huckel theory by one order of magnitude in ionic strength. Furthermore, we compare the predictions of the self-consistent theory with previous Monte Carlo simulation data for charged dielectric interfaces and show that the proposed approaches can also accurately handle the correlation effects induced by the surface charge in a parameter regime where the mean-field result significantly deviates from the Monte Carlo data. Then, we derive from the perturbative self-consistent scheme the one-loop theory of asymmetrically partitioned salt systems around a dielectrically homogeneous charged surface. It is shown that correlation effects originate in these systems from a competition between the salt screening loss at the interface driving the ions to the bulk region, and the interfacial counterion screening excess attracting them towards the surface. This competition can be quantified in terms of the characteristic surface charge σ(s)*=√(2ρ(b)/(πl(B)), where l(B) = 7 Å is the Bjerrum length. In the case of weak surface charges σ(s)≪σ(s)* where counterions form a diffuse layer, the interfacial salt screening loss is the dominant effect. As a result, correlation effects decrease the mean-field density of both coions and counterions. With an increase of the surface charge towards σ(s)*, the surface-attractive counterion screening excess starts to dominate, and correlation effects amplify in this regime the mean-field density of both type of ions. However, in the regime σ(s)>σ(s)*, the same counterion screening excess also results in a significant decrease of the electrostatic mean-field potential. This reduces in turn the mean-field counterion density far from the charged surface. We also show that for σ(s)≫σ(s)*, electrostatic correlations result in a charge inversion effect. However, the electrostatic coupling regime where this phenomenon takes place should be verified with Monte Carlo simulations since this parameter regime is located beyond the validity range of the one-loop theory.

[On-line processing mechanisms in text comprehension: a theoretical review on constructing situation models].

PubMed

Iseki, Ryuta

2004-12-01

This article reviewed research on construction of situation models during reading. To position variety of research in overall process appropriately, an unitary framework was devised in terms of three theories for on-line processing: resonance process, event-indexing model, and constructionist theory. Resonance process was treated as a basic activation mechanism in the framework. Event-indexing model was regarded as a screening system which selected and encoded activated information in situation models along with situational dimensions. Constructionist theory was considered to have a supervisory role based on coherence and explanation. From a view of the unitary framework, some problems concerning each theory were examined and possible interpretations were given. Finally, it was pointed out that there were little theoretical arguments on associative processing at global level and encoding text- and inference-information into long-term memory.

Is the cosmological constant screened in Liouville gravity with matter?

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

Inami, Takeo; Koyama, Yoji; Nakayama, Yu

In this study, there has been a proposal that infrared quantum effects of massless interacting field theories in de Sitter space may provide time-dependent screening of the cosmological constant. As a concrete model of the proposal, we study the three loop corrections to the energy–momentum tensor of massless λΦ 4 theory in the background of classical Liouville gravity in D = 2 dimensional de Sitter space. We find that the cosmological constant is screened, in sharp contrast to the massless λΦ 4 theory in D = 4 dimensions due to the sign difference between the cosmological constant of the Liouvillemore » gravity and that of the Einstein gravity. To argue for the robustness of our prediction, we introduce the concept of time-dependent infrared counter-terms and examine if they recover the de Sitter invariance in the λΦ 4 theory in comparison with the Sine–Gordon model, where it was possible.« less

Is the cosmological constant screened in Liouville gravity with matter?

DOE PAGES

Inami, Takeo; Koyama, Yoji; Nakayama, Yu; ...

2015-05-19

In this study, there has been a proposal that infrared quantum effects of massless interacting field theories in de Sitter space may provide time-dependent screening of the cosmological constant. As a concrete model of the proposal, we study the three loop corrections to the energy–momentum tensor of massless λΦ 4 theory in the background of classical Liouville gravity in D = 2 dimensional de Sitter space. We find that the cosmological constant is screened, in sharp contrast to the massless λΦ 4 theory in D = 4 dimensions due to the sign difference between the cosmological constant of the Liouvillemore » gravity and that of the Einstein gravity. To argue for the robustness of our prediction, we introduce the concept of time-dependent infrared counter-terms and examine if they recover the de Sitter invariance in the λΦ 4 theory in comparison with the Sine–Gordon model, where it was possible.« less

Using Testlet Response Theory to Examine Local Dependence in C-Tests

ERIC Educational Resources Information Center

Eckes, Thomas; Baghaei, Purya

2015-01-01

C-tests are gap-filling tests widely used to assess general language proficiency for purposes of placement, screening, or provision of feedback to language learners. C-tests consist of several short texts in which parts of words are missing. We addressed the issue of local dependence in C-tests using an explicit modeling approach based on testlet…

Gamma-ray solid laser: variety of work nuclei and host matrixes in Mendeleev Table screened with use of system of criteria based on joint GG&RH theory

NASA Astrophysics Data System (ADS)

Karyagin, Stanislav V.

2001-03-01

The hosts and nuclei-candidates (mass approximately 46 - 243, transition energy approximately 1 - 200 keV, decay's time 10-7 - 10+2 s) for gamma-laser (GL) realization are represented over Mendeleev Table. The choice of active media (nuclei-candidates, hosts) for GL is based on the joint theory of (gamma) -generation and radiation-heat regime which accounts a big complex of hindrances against GL and thus discards many tentative candidates. Nuclei- candidates are screened at the analyzing of data banks for nuclear transitions. Chosen candidates (approximately 20) could be used due to author's method SPTEN (Soft Prompt Transplantation of Excited Nuclei). The discarded tentative nuclei (approximately 80) with the life-times 10-6 - 10+2 are represented too. All analyzed long-lived (approximately 0.5 - 10+2 s) isomers are turned to be not fit for GL without use of very strong multi-wave Borrman effect even at the supposition of natural line's width. The application of the revealed candidates in two different (gamma) -laser's categories (residential and non- residential) is discussed.

Utilization of the Behavior Change Wheel framework to develop a model to improve cardiometabolic screening for people with severe mental illness.

PubMed

Mangurian, Christina; Niu, Grace C; Schillinger, Dean; Newcomer, John W; Dilley, James; Handley, Margaret A

2017-11-14

Individuals with severe mental illness (e.g., schizophrenia, bipolar disorder) die 10-25 years earlier than the general population, primarily from premature cardiovascular disease (CVD). Contributing factors are complex, but include systemic-related factors of poorly integrated primary care and mental health services. Although evidence-based models exist for integrating mental health care into primary care settings, the evidence base for integrating medical care into specialty mental health settings is limited. Such models are referred to as "reverse" integration. In this paper, we describe the application of an implementation science framework in designing a model to improve CVD outcomes for individuals with severe mental illness (SMI) who receive services in a community mental health setting. Using principles from the theory of planned behavior, focus groups were conducted to understand stakeholder perspectives of barriers to CVD risk factor screening and treatment identify potential target behaviors. We then applied results to the overarching Behavior Change Wheel framework, a systematic and theory-driven approach that incorporates the COM-B model (capability, opportunity, motivation, and behavior), to build an intervention to improve CVD risk factor screening and treatment for people with SMI. Following a stepped approach from the Behavior Change Wheel framework, a model to deliver primary preventive care for people that use community mental health settings as their de facto health home was developed. The CRANIUM (cardiometabolic risk assessment and treatment through a novel integration model for underserved populations with mental illness) model focuses on engaging community psychiatrists to expand their scope of practice to become responsible for CVD risk, with significant clinical decision support. The CRANIUM model was designed by integrating behavioral change theory and implementation theory. CRANIUM is feasible to implement, is highly acceptable to, and targets provider behavior change, and is replicable and efficient for helping to integrate primary preventive care services in community mental health settings. CRANIUM can be scaled up to increase CVD preventive care delivery and ultimately improve health outcomes among people with SMI served within a public mental health care system.

The electrostatic persistence length of polymers beyond the OSF limit.

PubMed

Everaers, R; Milchev, A; Yamakov, V

2002-05-01

We use large-scale Monte Carlo simulations to test scaling theories for the electrostatic persistence length l(e) of isolated, uniformly charged polymers with Debye-Hückel intrachain interactions in the limit where the screening length kappa(-1) exceeds the intrinsic persistence length of the chains. Our simulations cover a significantly larger part of the parameter space than previous studies. We observe no significant deviations from the prediction l(e) proportional to kappa(-2) by Khokhlov and Khachaturian which is based on applying the Odijk-Skolnick-Fixman theories of electrostatic bending rigidity and electrostatically excluded volume to the stretched de Gennes-Pincus-Velasco-Brochard polyelectrolyte blob chain. A linear or sublinear dependence of the persistence length on the screening length can be ruled out. We show that previous results pointing into this direction are due to a combination of excluded-volume and finite chain length effects. The paper emphasizes the role of scaling arguments in the development of useful representations for experimental and simulation data.

Contribution of dielectric screening to the total capacitance of few-layer graphene electrodes

DOE PAGES

Zhan, Cheng; Jiang, De-en

2016-02-17

We apply joint density functional theory (JDFT), which treats the electrode/electrolyte interface self-consistently, to an electric double-layer capacitor (EDLC) based on few-layer graphene electrodes. The JDFT approach allows us to quantify a third contribution to the total capacitance beyond quantum capacitance (C Q) and EDL capacitance (C EDL). This contribution arises from the dielectric screening of the electric field by the surface of the few-layer graphene electrode, and we therefore term it the dielectric capacitance (C Dielec). We find that C Dielec becomes significant in affecting the total capacitance when the number of graphene layers in the electrode is moremore » than three. In conclusion, our investigation sheds new light on the significance of the electrode dielectric screening on the capacitance of few-layer graphene electrodes.« less

Density Functional Theory and Beyond for Band-Gap Screening: Performance for Transition-Metal Oxides and Dichalcogenides.

PubMed

Li, Wenqing; Walther, Christian F J; Kuc, Agnieszka; Heine, Thomas

2013-07-09

The performance of a wide variety of commonly used density functionals, as well as two screened hybrid functionals (HSE06 and TB-mBJ), on predicting electronic structures of a large class of en vogue materials, such as metal oxides, chalcogenides, and nitrides, is discussed in terms of band gaps, band structures, and projected electronic densities of states. Contrary to GGA, hybrid functionals and GGA+U, both HSE06 and TB-mBJ are able to predict band gaps with an appreciable accuracy of 25% and thus allow the screening of various classes of transition-metal-based compounds, i.e., mixed or doped materials, at modest computational cost. The calculated electronic structures are largely unaffected by the choice of basis functions and software implementation, however, might be subject to the treatment of the core electrons.

Screening for mental illness: the merger of eugenics and the drug industry.

PubMed

Sharav, Vera Hassner

2005-01-01

The implementation of a recommendation by the President's New Freedom Commission (NFC) to screen the entire United States population--children first--for presumed, undetected, mental illness is an ill-conceived policy destined for disastrous consequences. The "pseudoscientific" methods used to screen for mental and behavioral abnormalities are a legacy from the discredited ideology of eugenics. Both eugenics and psychiatry suffer from a common philosophical fallacy that undermines the validity of their theories and prescriptions. Both are wed to a faith-based ideological assumption that mental and behavioral manifestations are biologically determined, and are, therefore, ameliorated by biological interventions. NFC promoted the Texas Medication Algorithm Project (TMAP) as a "model" medication treatment plan. The impact of TMAP is evident in the skyrocketing increase in psychotropic drug prescriptions for children and adults, and in the disproportionate expenditure for psychotropic drugs. The New Freedom Commission's screening for mental illness initiative is, therefore, but the first step toward prescribing drugs. The escalating expenditure for psychotropic drugs since TMAP leaves little doubt about who the beneficiaries of TMAP are. Screening for mental illness will increase their use.

Gravitational radiation from compact binary systems in screened modified gravity

NASA Astrophysics Data System (ADS)

Zhang, Xing; Liu, Tan; Zhao, Wen

2017-05-01

Screened modified gravity (SMG) is a kind of scalar-tensor theory with screening mechanisms, which can suppress the fifth force in dense regions and allow theories to evade the solar system and laboratory tests. In this paper, we investigate how the screening mechanisms in SMG affect the gravitational radiation damping effects, calculate in detail the rate of the energy loss due to the emission of tensor and scalar gravitational radiations, and derive their contributions to the change in the orbital period of the binary system. We find that the scalar radiation depends on the screened parameters and the propagation speed of scalar waves, and the scalar dipole radiation dominates the orbital decay of the binary system. For strongly self-gravitating bodies, all effects of scalar sector are strongly suppressed by the screening mechanisms in SMG. By comparing our results to observations of binary system PSR J 1738 +0333 , we place the stringent constraints on the screening mechanisms in SMG. As an application of these results, we focus on three specific models of SMG (chameleon, symmetron, and dilaton), and derive the constraints on the model parameters, respectively.

The ADDITION-Cambridge trial protocol: a cluster -- randomised controlled trial of screening for type 2 diabetes and intensive treatment for screen-detected patients.

PubMed

Echouffo-Tcheugui, Justin B; Simmons, Rebecca K; Williams, Kate M; Barling, Roslyn S; Prevost, A Toby; Kinmonth, Ann Louise; Wareham, Nicholas J; Griffin, Simon J

2009-05-12

The increasing prevalence of type 2 diabetes poses a major public health challenge. Population-based screening and early treatment for type 2 diabetes could reduce this growing burden. However, the benefits of such a strategy remain uncertain. The ADDITION-Cambridge study aims to evaluate the effectiveness and cost-effectiveness of (i) a stepwise screening strategy for type 2 diabetes; and (ii) intensive multifactorial treatment for people with screen-detected diabetes in primary care. 63 practices in the East Anglia region participated. Three undertook the pilot study, 33 were allocated to three groups: no screening (control), screening followed by intensive treatment (IT) and screening plus routine care (RC) in an unbalanced (1:3:3) randomisation. The remaining 27 practices were randomly allocated to IT and RC. A risk score incorporating routine practice data was used to identify people aged 40-69 years at high-risk of undiagnosed diabetes. In the screening practices, high-risk individuals were invited to take part in a stepwise screening programme. In the IT group, diabetes treatment is optimised through guidelines, target-led multifactorial treatment, audit, feedback, and academic detailing for practice teams, alongside provision of educational materials for newly diagnosed participants. Primary endpoints are modelled cardiovascular risk at one year, and cardiovascular mortality and morbidity at five years after diagnosis of diabetes. Secondary endpoints include all-cause mortality, development of renal and visual impairment, peripheral neuropathy, health service costs, self-reported quality of life, functional status and health utility. Impact of the screening programme at the population level is also assessed through measures of mortality, cardiovascular morbidity, health status and health service use among high-risk individuals. ADDITION-Cambridge is conducted in a defined high-risk group accessible through primary care. It addresses the feasibility of population-based screening for diabetes, as well as the benefits and costs of screening and intensive multifactorial treatment early in the disease trajectory. The intensive treatment algorithm is based on evidence from studies including individuals with clinically diagnosed diabetes and the education materials are informed by psychological theory. ADDITION-Cambridge will provide timely evidence concerning the benefits of early intensive treatment and will inform policy decisions concerning screening for type 2 diabetes. Current Controlled trials ISRCTN86769081.

The ADDITION-Cambridge trial protocol: a cluster – randomised controlled trial of screening for type 2 diabetes and intensive treatment for screen-detected patients

PubMed Central

Echouffo-Tcheugui, Justin B; Simmons, Rebecca K; Williams, Kate M; Barling, Roslyn S; Prevost, A Toby; Kinmonth, Ann Louise; Wareham, Nicholas J; Griffin, Simon J

2009-01-01

Background The increasing prevalence of type 2 diabetes poses a major public health challenge. Population-based screening and early treatment for type 2 diabetes could reduce this growing burden. However, the benefits of such a strategy remain uncertain. Methods and design The ADDITION-Cambridge study aims to evaluate the effectiveness and cost-effectiveness of (i) a stepwise screening strategy for type 2 diabetes; and (ii) intensive multifactorial treatment for people with screen-detected diabetes in primary care. 63 practices in the East Anglia region participated. Three undertook the pilot study, 33 were allocated to three groups: no screening (control), screening followed by intensive treatment (IT) and screening plus routine care (RC) in an unbalanced (1:3:3) randomisation. The remaining 27 practices were randomly allocated to IT and RC. A risk score incorporating routine practice data was used to identify people aged 40–69 years at high-risk of undiagnosed diabetes. In the screening practices, high-risk individuals were invited to take part in a stepwise screening programme. In the IT group, diabetes treatment is optimised through guidelines, target-led multifactorial treatment, audit, feedback, and academic detailing for practice teams, alongside provision of educational materials for newly diagnosed participants. Primary endpoints are modelled cardiovascular risk at one year, and cardiovascular mortality and morbidity at five years after diagnosis of diabetes. Secondary endpoints include all-cause mortality, development of renal and visual impairment, peripheral neuropathy, health service costs, self-reported quality of life, functional status and health utility. Impact of the screening programme at the population level is also assessed through measures of mortality, cardiovascular morbidity, health status and health service use among high-risk individuals. Discussion ADDITION-Cambridge is conducted in a defined high-risk group accessible through primary care. It addresses the feasibility of population-based screening for diabetes, as well as the benefits and costs of screening and intensive multifactorial treatment early in the disease trajectory. The intensive treatment algorithm is based on evidence from studies including individuals with clinically diagnosed diabetes and the education materials are informed by psychological theory. ADDITION-Cambridge will provide timely evidence concerning the benefits of early intensive treatment and will inform policy decisions concerning screening for type 2 diabetes. Trial registration Current Controlled trials ISRCTN86769081 PMID:19435491

Use of theory to plan or evaluate guideline implementation among physicians: a scoping review.

PubMed

Liang, Laurel; Bernhardsson, Susanne; Vernooij, Robin W M; Armstrong, Melissa J; Bussières, André; Brouwers, Melissa C; Gagliardi, Anna R

2017-02-27

Guidelines support health care decision-making and high quality care and outcomes. However, their implementation is sub-optimal. Theory-informed, tailored implementation is associated with guideline use. Few guideline implementation studies published up to 1998 employed theory. This study aimed to describe if and how theory is now used to plan or evaluate guideline implementation among physicians. A scoping review was conducted. MEDLINE, EMBASE, and The Cochrane Library were searched from 2006 to April 2016. English language studies that planned or evaluated guideline implementation targeted to physicians based on explicitly named theory were eligible. Screening and data extraction were done in duplicate. Study characteristics and details about theory use were analyzed. A total of 1244 published reports were identified, 891 were unique, and 716 were excluded based on title and abstract. Among 175 full-text articles, 89 planned or evaluated guideline implementation targeted to physicians; 42 (47.2%) were based on theory and included. The number of studies using theory increased yearly and represented a wide array of countries, guideline topics and types of physicians. The Theory of Planned Behavior (38.1%) and the Theoretical Domains Framework (23.8%) were used most frequently. Many studies rationalized choice of theory (83.3%), most often by stating that the theory described implementation or its determinants, but most failed to explicitly link barriers with theoretical constructs. The majority of studies used theory to inform surveys or interviews that identified barriers of guideline use as a preliminary step in implementation planning (76.2%). All studies that evaluated interventions reported positive impact on reported physician or patient outcomes. While the use of theory to design or evaluate interventions appears to be increasing over time, this review found that one half of guideline implementation studies were based on theory and many of those provided scant details about how theory was used. This limits interpretation and replication of those interventions, and seems to result in multifaceted interventions, which may not be feasible outside of scientific investigation. Further research is needed to better understand how to employ theory in guideline implementation planning or evaluation.

Charged particle layers in the Debye limit.

PubMed

Golden, Kenneth I; Kalman, Gabor J; Kyrkos, Stamatios

2002-09-01

We develop an equivalent of the Debye-Hückel weakly coupled equilibrium theory for layered classical charged particle systems composed of one single charged species. We consider the two most important configurations, the charged particle bilayer and the infinite superlattice. The approach is based on the link provided by the classical fluctuation-dissipation theorem between the random-phase approximation response functions and the Debye equilibrium pair correlation function. Layer-layer pair correlation functions, screened and polarization potentials, static structure functions, and static response functions are calculated. The importance of the perfect screening and compressibility sum rules in determining the overall behavior of the system, especially in the r--> infinity limit, is emphasized. The similarities and differences between the quasi-two-dimensional bilayer and the quasi-three-dimensional superlattice are highlighted. An unexpected behavior that emerges from the analysis is that the screened potential, the correlations, and the screening charges carried by the individual layers exhibit a marked nonmonotonic dependence on the layer separation.

A new yield and failure theory for composite materials under static and dynamic loading

DOE PAGES

Daniel, Isaac M.; Daniel, Sam M.; Fenner, Joel S.

2017-09-12

In order to facilitate and accelerate the process of introducing, evaluating and adopting new material systems, it is important to develop/establish comprehensive and effective procedures of characterization, modeling and failure prediction of composite structures based on the properties of the constituent materials, e. g., fibers, matrix, and the single ply or lamina. A new yield/failure theory is proposed for predicting lamina yielding and failure under multi-axial states of stress including strain rate effects. It is based on the equivalent stress concept derived from energy principles and is expressed in terms of a single criterion. It is presented in the formmore » of master yield and failure envelopes incorporating strain rate effects. The theory can be further adapted and extended to the prediction of in situ first ply yielding and failure (FPY and FPF) and progressive damage of multi-directional laminates under static and dynamic loadings. The significance of this theory is that it allows for rapid screening of new composite materials without extensive testing and offers easily implemented design tools.« less

A new yield and failure theory for composite materials under static and dynamic loading

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

Daniel, Isaac M.; Daniel, Sam M.; Fenner, Joel S.

In order to facilitate and accelerate the process of introducing, evaluating and adopting new material systems, it is important to develop/establish comprehensive and effective procedures of characterization, modeling and failure prediction of composite structures based on the properties of the constituent materials, e. g., fibers, matrix, and the single ply or lamina. A new yield/failure theory is proposed for predicting lamina yielding and failure under multi-axial states of stress including strain rate effects. It is based on the equivalent stress concept derived from energy principles and is expressed in terms of a single criterion. It is presented in the formmore » of master yield and failure envelopes incorporating strain rate effects. The theory can be further adapted and extended to the prediction of in situ first ply yielding and failure (FPY and FPF) and progressive damage of multi-directional laminates under static and dynamic loadings. The significance of this theory is that it allows for rapid screening of new composite materials without extensive testing and offers easily implemented design tools.« less

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

Daniel, Isaac M.

To facilitate and accelerate the process of introducing, evaluating and adopting of new material systems, it is important to develop/establish comprehensive and effective procedures of characterization, modeling and failure prediction of structural laminates based on the properties of the constituent materials, e. g., fibers, matrix, and the single ply or lamina. A new failure theory, the Northwestern (NU-Daniel) theory, has been proposed for predicting lamina yielding and failure under multi-axial states of stress including strain rate effects. It is primarily applicable to matrix-dominated interfiber/interlaminar failures. It is based on micromechanical failure mechanisms but is expressed in terms of easily measuredmore » macroscopic lamina stiffness and strength properties. It is presented in the form of a master failure envelope incorporating strain rate effects. The theory was further adapted and extended to the prediction of in situ first ply yielding and failure (FPY and FPF) and progressive failure of multi-directional laminates under static and dynamic loadings. The significance of this theory is that it allows for rapid screening of new composite materials without very extensive testing and offers easily implemented design tools.« less

Fast Screening Technology for Drug Emergency Management: Predicting Suspicious SNPs for ADR with Information Theory-based Models.

PubMed

Liang, Zhaohui; Liu, Jun; Huang, Jimmy X; Zeng, Xing

2018-01-01

The genetic polymorphism of Cytochrome P450 (CYP 450) is considered as one of the main causes for adverse drug reactions (ADRs). In order to explore the latent correlations between ADRs and potentially corresponding single-nucleotide polymorphism (SNPs) in CYP450, three algorithms based on information theory are used as the main method to predict the possible relation. The study uses a retrospective case-control study to explore the potential relation of ADRs to specific genomic locations and single-nucleotide polymorphism (SNP). The genomic data collected from 53 healthy volunteers are applied for the analysis, another group of genomic data collected from 30 healthy volunteers excluded from the study are used as the control group. The SNPs respective on five loci of CYP2D6*2,*10,*14 and CYP1A2*1C, *1F are detected by the Applied Biosystem 3130xl. The raw data is processed by ChromasPro to detect the specific alleles on the above loci from each sample. The secondary data are reorganized and processed by R combined with the reports of ADRs from clinical reports. Three information theory based algorithms are implemented for the screening task: JMI, CMIM, and mRMR. If a SNP is selected by more than two algorithms, we are confident to conclude that it is related to the corresponding ADR. The selection results are compared with the control decision tree + LASSO regression model. In the study group where ADRs occur, 10 SNPs are considered relevant to the occurrence of a specific ADR by the combined information theory model. In comparison, only 5 SNPs are considered relevant to a specific ADR by the decision tree + LASSO regression model. In addition, the new method detects more relevant pairs of SNP and ADR which are affected by both SNP and dosage. This implies that the new information theory based model is effective to discover correlations of ADRs and CYP 450 SNPs and is helpful in predicting the potential vulnerable genotype for some ADRs. The newly proposed information theory based model has superiority performance in detecting the relation between SNP and ADR compared to the decision tree + LASSO regression model. The new model is more sensitive to detect ADRs compared to the old method, while the old method is more reliable. Therefore, the selection criteria for selecting algorithms should depend on the pragmatic needs. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

Two-color Fermi-liquid theory for transport through a multilevel Kondo impurity

NASA Astrophysics Data System (ADS)

Karki, D. B.; Mora, Christophe; von Delft, Jan; Kiselev, Mikhail N.

2018-05-01

We consider a quantum dot with K ≥2 orbital levels occupied by two electrons connected to two electric terminals. The generic model is given by a multilevel Anderson Hamiltonian. The weak-coupling theory at the particle-hole symmetric point is governed by a two-channel S =1 Kondo model characterized by intrinsic channels asymmetry. Based on a conformal field theory approach we derived an effective Hamiltonian at a strong-coupling fixed point. The Hamiltonian capturing the low-energy physics of a two-stage Kondo screening represents the quantum impurity by a two-color local Fermi liquid. Using nonequilibrium (Keldysh) perturbation theory around the strong-coupling fixed point we analyze the transport properties of the model at finite temperature, Zeeman magnetic field, and source-drain voltage applied across the quantum dot. We compute the Fermi-liquid transport constants and discuss different universality classes associated with emergent symmetries.

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

Bose, Benjamin; Koyama, Kazuya, E-mail: benjamin.bose@port.ac.uk, E-mail: kazuya.koyama@port.ac.uk

We develop a code to produce the power spectrum in redshift space based on standard perturbation theory (SPT) at 1-loop order. The code can be applied to a wide range of modified gravity and dark energy models using a recently proposed numerical method by A.Taruya to find the SPT kernels. This includes Horndeski's theory with a general potential, which accommodates both chameleon and Vainshtein screening mechanisms and provides a non-linear extension of the effective theory of dark energy up to the third order. Focus is on a recent non-linear model of the redshift space power spectrum which has been shownmore » to model the anisotropy very well at relevant scales for the SPT framework, as well as capturing relevant non-linear effects typical of modified gravity theories. We provide consistency checks of the code against established results and elucidate its application within the light of upcoming high precision RSD data.« less

Toward a Theory of Web-Mediated Knowledge Synthesis: How Advanced Learners Used the Web to Construct Knowledge about Climate Change Behavior

ERIC Educational Resources Information Center

DeSchryver, Michael

2012-01-01

This dissertation utilized a multiple case study design to explore how advanced learners synthesize information about ill-structured topics when reading-to-learn and reading-to-do on the Web. Eight graduate students provided data in the form of think-alouds, interviews, screen video, digital trails, and task artifacts. Data analysis was based on…

Doctors' perspectives on PSA testing illuminate established differences in prostate cancer screening rates between Australia and the UK: a qualitative study

PubMed Central

Pickles, Kristen; Carter, Stacy M; Rychetnik, Lucie; Entwistle, Vikki A

2016-01-01

Objectives To examine how general practitioners (GPs) in the UK and GPs in Australia explain their prostate-specific antigen (PSA) testing practices and to illuminate how these explanations are similar and how they are different. Design A grounded theory study. Setting Primary care practices in Australia and the UK. Participants 69 GPs in Australia (n=40) and the UK (n=29). We included GPs of varying ages, sex, clinical experience and patient populations. All GPs interested in participating in the study were included. Results GPs' accounts revealed fundamental differences in whether and how prostate cancer screening occurred in their practice and in the broader context within which they operate. The history of prostate screening policy, organisational structures and funding models appeared to drive more prostate screening in Australia and less in the UK. In Australia, screening processes and decisions were mostly at the discretion of individual clinicians, and varied considerably, whereas the accounts of UK GPs clearly reflected a consistent, organisationally embedded approach based on local evidence-based recommendations to discourage screening. Conclusions The GP accounts suggested that healthcare systems, including historical and current organisational and funding structures and rules, collectively contribute to how and why clinicians use the PSA test and play a significant role in creating the mindlines that GPs employ in their clinic. Australia's recently released consensus guidelines may support more streamlined and consistent care. However, if GP mindlines and thus routine practice in Australia are to shift, to ultimately reduce unnecessary or harmful prostate screening, it is likely that other important drivers at all levels of the screening process will need to be addressed. PMID:27920082

Cosmic Tsunamis in Modified Gravity: Disruption of Screening Mechanisms from Scalar Waves.

PubMed

Hagala, R; Llinares, C; Mota, D F

2017-03-10

Extending general relativity by adding extra degrees of freedom is a popular approach for explaining the accelerated expansion of the Universe and to build high energy completions of the theory of gravity. The presence of such new degrees of freedom is, however, tightly constrained from several observations and experiments that aim to test general relativity in a wide range of scales. The viability of a given modified theory of gravity, therefore, strongly depends on the existence of a screening mechanism that suppresses the extra degrees of freedom. We perform simulations, and find that waves propagating in the new degrees of freedom can significantly impact the efficiency of some screening mechanisms, thereby threatening the viability of these modified gravity theories. Specifically, we show that the waves produced in the symmetron model can increase the amplitude of the fifth force and the parametrized post Newtonian parameters by several orders of magnitude.

Cosmic Tsunamis in Modified Gravity: Disruption of Screening Mechanisms from Scalar Waves

NASA Astrophysics Data System (ADS)

Hagala, R.; Llinares, C.; Mota, D. F.

2017-03-01

Extending general relativity by adding extra degrees of freedom is a popular approach for explaining the accelerated expansion of the Universe and to build high energy completions of the theory of gravity. The presence of such new degrees of freedom is, however, tightly constrained from several observations and experiments that aim to test general relativity in a wide range of scales. The viability of a given modified theory of gravity, therefore, strongly depends on the existence of a screening mechanism that suppresses the extra degrees of freedom. We perform simulations, and find that waves propagating in the new degrees of freedom can significantly impact the efficiency of some screening mechanisms, thereby threatening the viability of these modified gravity theories. Specifically, we show that the waves produced in the symmetron model can increase the amplitude of the fifth force and the parametrized post Newtonian parameters by several orders of magnitude.

Applying normalization process theory to understand implementation of a family violence screening and care model in maternal and child health nursing practice: a mixed method process evaluation of a randomised controlled trial.

PubMed

Hooker, Leesa; Small, Rhonda; Humphreys, Cathy; Hegarty, Kelsey; Taft, Angela

2015-03-28

In Victoria, Australia, Maternal and Child Health (MCH) services deliver primary health care to families with children 0-6 years, focusing on health promotion, parenting support and early intervention. Family violence (FV) has been identified as a major public health concern, with increased prevalence in the child-bearing years. Victorian Government policy recommends routine FV screening of all women attending MCH services. Using Normalization Process Theory (NPT), we aimed to understand the barriers and facilitators of implementing an enhanced screening model into MCH nurse clinical practice. NPT informed the process evaluation of a pragmatic, cluster randomised controlled trial in eight MCH nurse teams in metropolitan Melbourne, Victoria, Australia. Using mixed methods (surveys and interviews), we explored the views of MCH nurses, MCH nurse team leaders, FV liaison workers and FV managers on implementation of the model. Quantitative data were analysed by comparing proportionate group differences and change within trial arm over time between interim and impact nurse surveys. Qualitative data were inductively coded, thematically analysed and mapped to NPT constructs (coherence, cognitive participation, collective action and reflexive monitoring) to enhance our understanding of the outcome evaluation. MCH nurse participation rates for interim and impact surveys were 79% (127/160) and 71% (114/160), respectively. Twenty-three key stakeholder interviews were completed. FV screening work was meaningful and valued by participants; however, the implementation coincided with a significant (government directed) change in clinical practice which impacted on full engagement with the model (coherence and cognitive participation). The use of MCH nurse-designed FV screening/management tools in focussed women's health consultations and links with FV services enhanced the participants' work (collective action). Monitoring of FV work (reflexive monitoring) was limited. The use of theory-based process evaluation helped identify both what inhibited and enhanced intervention effectiveness. Successful implementation of an enhanced FV screening model for MCH nurses occurred in the context of focussed women's health consultations, with the use of a maternal health and wellbeing checklist and greater collaboration with FV services. Improving links with these services and the ongoing appraisal of nurse work would overcome the barriers identified in this study.

Workplace-based breast cancer screening intervention in china.

PubMed

Ma, Grace X; Yin, Lihong; Gao, Wanzhen; Tan, Yin; Liu, Ran; Fang, Carolyn; Ma, Xiang S

2012-02-01

Breast cancer continues to be the primary cause of death among East and Southeast Asian women. Although China, the most populous country in the world, is experiencing unprecedented economic growth, its health care system has yet to benefit from the current economic prosperity. Indeed, studies have shown a consistent increase in breast cancer rates among Chinese women over the past two decades in the absence of breast cancer screening guidelines. The primary objective of this study was to examine the impact of a workplace intervention on increasing breast cancer screening rates. The study was implemented at eight worksites in Nanjing, four of which were assigned to the intervention group (n = 232) and four to the control group (n = 221). The intervention group received breast cancer education and screening navigation. The control group was provided with general cancer education and received a delayed intervention after completion of the study. Study measures were completed at pre- and postprogram and at 6-month follow-up to assess uptake of mammography. Baseline mammography use was low among both intervention and control groups. However, exposure to the workplace intervention dramatically increased the uptake of mammography from 10.3% at baseline to 72.6% at 6-month follow-up in the intervention group (P < 0.001). Findings provide preliminary evidence that the implementation of a comprehensive workplace breast cancer screening intervention program in China can lead to increased uptake of mammography. These data may help facilitate the development of theory-based workplace cancer prevention programs and screening guidelines in China. A workplace-based multifaceted intervention could have a strong impact in breast cancer prevention and early detection among women in China. ©2011 AACR.

Carrier mobility in double-helix DNA and RNA: A quantum chemistry study with Marcus-Hush theory.

PubMed

Wu, Tao; Sun, Lei; Shi, Qi; Deng, Kaiming; Deng, Weiqiao; Lu, Ruifeng

2016-12-21

Charge mobilities of six DNAs and RNAs have been computed using quantum chemistry calculation combined with the Marcus-Hush theory. Based on this simulation model, we obtained quite reasonable results when compared with the experiment, and the obtained charge mobility strongly depends on the molecular reorganization and electronic coupling. Besides, we find that hole mobilities are larger than electron mobilities no matter in DNAs or in RNAs, and the hole mobility of 2L8I can reach 1.09 × 10 -1 cm 2 V -1 s -1 which can be applied in the molecular wire. The findings also show that our theoretical model can be regarded as a promising candidate for screening DNA- and RNA-based molecular electronic devices.

Carrier mobility in double-helix DNA and RNA: A quantum chemistry study with Marcus-Hush theory

NASA Astrophysics Data System (ADS)

Wu, Tao; Sun, Lei; Shi, Qi; Deng, Kaiming; Deng, Weiqiao; Lu, Ruifeng

2016-12-01

Charge mobilities of six DNAs and RNAs have been computed using quantum chemistry calculation combined with the Marcus-Hush theory. Based on this simulation model, we obtained quite reasonable results when compared with the experiment, and the obtained charge mobility strongly depends on the molecular reorganization and electronic coupling. Besides, we find that hole mobilities are larger than electron mobilities no matter in DNAs or in RNAs, and the hole mobility of 2L8I can reach 1.09 × 10-1 cm2 V-1 s-1 which can be applied in the molecular wire. The findings also show that our theoretical model can be regarded as a promising candidate for screening DNA- and RNA-based molecular electronic devices.

Electron collection theory for a D-region subsonic blunt electrostatic probe

NASA Technical Reports Server (NTRS)

Wai-Kwong Lai, T.

1974-01-01

Blunt probe theory for subsonic flow in a weakly ionized and collisional gas is reviewed, and an electron collection theory for the relatively unexplored case, Deybye length approximately 1, which occurs in the lower ionosphere (D-region), is developed. It is found that the dimensionless Debye length is no longer an electric field screening parameter, and the space charge field effect can be negelected. For ion collection, Hoult-Sonin theory is recognized as a correct description of the thin, ion density-perturbed layer adjacent the blunt probe surface. The large volume with electron density perturbed by a positively biased probe renders the usual thin boundary layer analysis inapplicable. Theories relating free stream conditions to the electron collection rate for both stationary and moving blunt probes are obtained. A model based on experimental nonlinear electron drift velocity data is proposed. For a subsonically moving probe, it is found that the perturbed region can be divided into four regions with distinct collection mechanisms.

Disformal theories of gravity: from the solar system to cosmology

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

Sakstein, Jeremy, E-mail: j.a.sakstein@damtp.cam.ac.uk

This paper is concerned with theories of gravity that contain a scalar coupled both conformally and disformally to matter through the metric. By systematically deriving the non-relativistic limit, it is shown that no new non-linear screening mechanisms are present beyond the Vainshtein mechanism and chameleon-like screening. If one includes the cosmological expansion of the universe, disformal effects that are usually taken to be absent can be present in the solar system. When the conformal factor is absent, fifth-forces can be screened on all scales when the cosmological field is slowly-rolling. We investigate the cosmology of these models and use localmore » tests of gravity to place new constraints on the disformal coupling and find M ∼> O(eV), which is not competitive with laboratory tests. Finally, we discuss the future prospects for testing these theories and the implications for other theories of modified gravity. In particular, the Vainshtein radius of solar system objects can be altered from the static prediction when cosmological time-derivatives are non-negligible.« less

Perceived Benefits and Barriers of Cervical Cancer Screening Among Chinese American Women.

PubMed

Tung, Wei-Chen; Lu, Minggen; Granner, Michelle

2017-03-01

To explore the perceived benefits and barriers to cervical cancer screening among Chinese American women using stages of the Transtheoretical Model of Change.
. Cross-sectional design with self-report surveys. 
. Chinese communities (e.g., churches, supermarkets, restaurants) in Northern California and Northern Nevada. 
. 121 Chinese women aged 21-65 years living in Northern California and Northern Nevada. 
. A snowball sampling technique using personal contacts was used.
. Stages of change and perceived benefits and barriers to cervical cancer screening. 
. Participants in the action/maintenance stage were most likely to believe that cervical cancer was treatable if caught early. Women in the contemplation/preparation stage were more likely to state that they worried about or feared screening, that it was too expensive, and that they would want to use Chinese medicine to cure an illness before trying Western medicine. Women in the precontemplation/relapse stage were most likely to report that they did not know where to get screened and that their partner would not want them to be screened.
. Perceived benefits and barriers to screening were differentially associated with the stages of change. Results may support culturally sensitive and theory-based programs to improve screening rates among Chinese American women. 
. The results suggest the importance of cultural sensitivity among nursing providers when working with Chinese Americans to provide more relevant, holistic care.

Effects of Application of Social Marketing Theory and the Health Belief Model in Promoting Cervical Cancer Screening among Targeted Women in Sisaket Province, Thailand.

PubMed

Wichachai, Suparp; Songserm, Nopparat; Akakul, Theerawut; Kuasiri, Chanapong

2016-01-01

Cervical cancer is a major public health problem in Thailand, being ranked second only to breast cancer. Thai women have been reported to have a low rate of cervical cancer screening (27.7% of the 80% goal of WHO). We therefore aimed to apply the social marketing theory and health belief model in promoting cervical cancer screening in Kanthararom District, Sisaket Province. A total of 92 from 974 targeted women aged 3060 years were randomly divided into two groups. The experimental group underwent application of social marketing theory and a health belief model program promoting cervical cancer screening while the control group received normal services. Two research tools were used: (1) application of social marketing theory and health belief model program and (2) questionnaire used to evaluate perceptions of cervical cancer. Descriptive and inferential statistics including paired sample ttest and independent ttest were used to analyze the data. After the program had been used, the mean score of perception of cervical cancer of experimental group was at a higher level (x=4.09; S.D. =0.30), than in the control group (x=3.82; S.D. =0.20) with statistical significance (p<0.001). This research demonstrated an appropriate communication process in behavioral modification to prevent cervical cancer. It can be recommended that this program featuring social marketing and the health belief model be used to promote cervical cancer screening in targeted women and it can be promoted as a guideline for other health services, especially in health promotion and disease prevention.

The influence of knowledge and perception of the risk of cervical cancer on screening behavior in mainland Chinese women.

PubMed

Gu, Can; Chan, Carmen W H; Twinn, Sheila; Choi, Kai Chow

2012-12-01

Theories of health behavior and empirical research highlight the risk perception as a significant factor for people adopting cancer screening. However, screening uptakes and risk perception of cervical cancer in mainland Chinese women remains unknown. This paper adopted the protection motivation theory (PMT) to examine Chinese women's knowledge and perceptions of cervical cancer risk and factors influencing utilization of cervical screening. A self-administered questionnaire was completed by 167 participants in mainland China (79 nonscreened and 88 screened women) in 2007 which consisted of four sections: background information, women's attendance pattern for cervical screening, perceptions related to body health and knowledge about cervical cancer and screening, and PMT measures. All women considered themselves at low risk of cervical cancer. No significant association was observed between previous screening uptake and PMT variables. Using multivariate analysis, having children, a perception that visiting doctors regularly is important to health, average and high levels of knowledge about cervical screening were significantly associated with having been received screening. Chinese women demonstrated an unrealistic optimism about their personal risk of cervical cancer. The findings do not support an association between risk perception and screening uptake. In spite of this, current findings revealed some possible factors influencing women's screening behavior. This study highlights the significance of knowledge and culturally-relevant health behavior and beliefs about cervical screening for Chinese women in determining whether or not they receive screening. The promotion of cervical cancer prevention and early detection should be integrated into public education about women's health. Copyright © 2011 John Wiley & Sons, Ltd.

Predictors of Self-care among the Elderly with Diabetes Type 2: Using Social Cognitive Theory.

PubMed

Borhaninejad, Vahidreza; Iranpour, Abedin; Shati, Mohsen; Tahami, Ahmad Naghibzadeh; Yousefzadeh, Gholamrezan; Fadayevatan, Reza

Diabetes is one of the most common chronic diseases among the elderly and is also a very serious health problem. Adopting theory-based self-care behaviors is an effective means in managing such diseases. This study aimed to determine the predictors of diabetes self-care in the elderly in Kerman based on a social cognitive theory. In this cross-sectional study, 384 elderly diabetic patients who had referred to health screening centers in Kerman were chosen via cluster sampling. To collect information about self-care and its predictors, Toobert Glasgow's diabetes self-efficacy scale as well as a questionnaire was used which was based on social cognitive theory constructs. The validity and reliability of the questionnaire was confirmed. The data were analyzed using Pearson correlation and linear regression analysis in SPSS software 17. Among the subjects, 67.37% (252) had poor self-care ability; 29.14% (109) had average ability, and 3.40% (13) enjoyed a proper level of self- care ability. There was a significant relationship between the constructs of the social cognitive theory (knowledge, self- efficacy, social support, outcome expectations, outcome expectancy and self-regulation) and the self-care score. Furthermore, the mentioned constructs could predict 0.47% of the variance of the self-care behaviors. self-care behaviors in this study were poor. Therefore, it is necessary to develop an educational intervention based on cognitive theory constructs with the goal of properly managing diabetes in the elderly patients. Copyright © 2016 Diabetes India. Published by Elsevier Ltd. All rights reserved.

Implementing evidence-based practices in an emergency department: contradictions exposed when prioritising a flow culture.

PubMed

Kirk, Jeanette W; Nilsen, Per

2016-02-01

An emergency department is typically a place of high activity where practitioners care for unanticipated presentations, which yields a flow culture so that actions that secure available beds are prioritised by the practitioners. How does the flow culture in an emergency department influence nurses' use of a research-based clinical guideline and a nutrition screening routine. Ethnographic fieldwork was carried out over three months. The first author followed nurses, medical secretaries and doctors in the emergency department. Data were also collected by means of semi-structured interviews. An activity system analysis, as described in the Cultural Historical Activity Theory, was conducted to identify various contradictions that could exist between different parts of the activity system. The main contradiction identified was that guidelines and screening routines provided a flow stop. Four associated contradictions were identified: insufficient time to implement guidelines; guilty conscience due to perceived nonadherence to evidence-based practices; newcomers having different priorities; and conflicting views of what constituted being a professional. We found that research-supported guidelines and screening routines were not used if they were perceived to stop the patient flow, suggesting that the practice was not fully evidence based. © 2016 The Authors. Journal of Clinical Nursing Published by John Wiley & Sons Ltd.

Implicit Age Cues in Resumes: Subtle Effects on Hiring Discrimination

PubMed Central

Derous, Eva; Decoster, Jeroen

2017-01-01

Anonymous resume screening, as assumed, does not dissuade age discriminatory effects. Building on job market signaling theory, this study investigated whether older applicants may benefit from concealing explicitly mentioned age signals on their resumes (date of birth) or whether more implicit/subtle age cues on resumes (older-sounding names/old-fashioned extracurricular activities) may lower older applicants’ hirability ratings. An experimental study among 610 HR professionals using a mixed factorial design showed hiring discrimination of older applicants based on implicit age cues in resumes. This effect was more pronounced for older raters. Concealing one’s date of birth led to overall lower ratings. Study findings add to the limited knowledge on the effects of implicit age cues on hiring discrimination in resume screening and the usefulness of anonymous resume screening in the context of age. Implications for research and practice are discussed. PMID:28848463

Colorectal Cancer Screening at the Nexus of HIV, Minority Statuses, and Cultural Safety

ERIC Educational Resources Information Center

Ka'opua, Lana Sue I.; Diaz, Tressa P.; Park, Soon H.; Bowen, Talita; Patrick, Kevin; Tamang, Suresh; Braun, Kathryn L.

2014-01-01

Background: The incidence of non-AIDS-defining cancers has increased significantly among persons living with HIV (PLHIV). Screening education is recommended. Purpose: Social learning, minority stress, and cultural safety theories informed this pilot to assess the feasibility of a colorectal cancer screening intervention targeted to PLHIV, with…

Using Spelling to Screen Bilingual Kindergarteners at Risk for Reading Difficulties

ERIC Educational Resources Information Center

Chua, Shi Min; Rickard Liow, Susan J.; Yeong, Stephanie H. M.

2016-01-01

For bilingual children, the results of language and literacy screening tools are often hard to interpret. This leads to late referral for specialized assessment or inappropriate interventions. To facilitate the early identification of reading difficulties in English, we developed a method of screening that is theory-driven yet suitable for…

Further Evidence on the Weak and Strong Versions of the Screening Hypothesis in Greece.

ERIC Educational Resources Information Center

Lambropoulos, Haris S.

1992-01-01

Uses Greek data for 1981 and 1985 to test screening hypothesis by replicating method proposed by Psacharopoulos. Credentialism, or sheepskin effect of education, directly challenges human capital theory, which views education as a productivity augmenting process. Results do not support the strong version of the screening hypothesis and suggest…

Screening fifth forces in k-essence and DBI models

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

Brax, Philippe; Burrage, Clare; Davis, Anne-Christine, E-mail: Philippe.Brax@cea.fr, E-mail: Clare.Burrage@nottingham.ac.uk, E-mail: A.C.Davis@damtp.cam.ac.uk

New fifth forces have not yet been detected in the laboratory or in the solar system, hence it is typically difficult to introduce new light scalar fields that would mediate such forces. In recent years it has been shown that a number of non-linear scalar field theories allow for a dynamical mechanism, such as the Vainshtein and chameleon ones, that suppresses the strength of the scalar fifth force in experimental environments. This is known as screening, however it is unclear how common screening is within non-linear scalar field theories. k-essence models are commonly studied examples of non-linear models, with DBImore » as the best motivated example, and so we ask whether these non-linearities are able to screen a scalar fifth force. We find that a Vainshtein-like screening mechanism exists for such models although with limited applicability. For instance, we cannot find a screening mechanism for DBI models. On the other hand, we construct a large class of k-essence models which lead to the acceleration of the Universe in the recent past for which the fifth force mediated by the scalar can be screened.« less

Applying the Theory of Planned Behavior to Explain Women's Role in Prostate Cancer Screening.

PubMed

Di Sarra, Luca; Ghezzi, Valerio; Eastland, Taryn Yolanda; Antonini, Francesca; Scialó, Gennaro; Zega, Maurizio; Alvaro, Rosaria

2015-01-01

To test the suitability of the theory of planned behavior (TPB) for explaining Italian women's role in prostatic cancer screening promotion. A descriptive, cross-sectional, online self-report survey was conducted with a convenience sample of 235 Italian women. Variables included attitudes women's role, perceived behavioral control, subjective norm, behavioral intention, and prostate cancer screening promotion behavior. A survey composed of the Eastland Prostate Cancer Survey subscales that were consistent with the TPB was distributed via e-mail to potential participants. The survey was live for 12 weeks (March 2013 to May 2013). Responses were collated with eSurv.org. Data were analyzed using latent path analysis and structural equation modeling. Behavioral intentions in promoting prostate cancer screening significantly predicted the likelihood of the Italian women to adopt self-reported prostate cancer screening promotion behaviors. In addition, the exclusive direct impact of the intentions explained 39% of the variance in self-reported behaviors. The TPB could represent a good framework to explain the role of Italian women in prevention behaviors related to the prostatic screening domain. Consistent with literature findings in social and nursing sciences, the intention to promote prostate cancer screening was a powerful "predictor" of the behavior itself.

Many-body perturbation theory and non-perturbative approaches: screened interaction as the key ingredient

NASA Astrophysics Data System (ADS)

Tarantino, Walter; Mendoza, Bernardo S.; Romaniello, Pina; Berger, J. A.; Reining, Lucia

2018-04-01

Many-body perturbation theory is often formulated in terms of an expansion in the dressed instead of the bare Green’s function, and in the screened instead of the bare Coulomb interaction. However, screening can be calculated on different levels of approximation, and it is important to define what is the most appropriate choice. We explore this question by studying a zero-dimensional model (so called ‘one-point model’) that retains the structure of the full equations. We study both linear and non-linear response approximations to the screening. We find that an expansion in terms of the screening in the random phase approximation is the most promising way for an application in real systems. Moreover, by making use of the nonperturbative features of the Kadanoff-Baym equation for the one-body Green’s function, we obtain an approximate solution in our model that is very promising, although its applicability to real systems has still to be explored.

COLA with scale-dependent growth: applications to screened modified gravity models

NASA Astrophysics Data System (ADS)

Winther, Hans A.; Koyama, Kazuya; Manera, Marc; Wright, Bill S.; Zhao, Gong-Bo

2017-08-01

We present a general parallelized and easy-to-use code to perform numerical simulations of structure formation using the COLA (COmoving Lagrangian Acceleration) method for cosmological models that exhibit scale-dependent growth at the level of first and second order Lagrangian perturbation theory. For modified gravity theories we also include screening using a fast approximate method that covers all the main examples of screening mechanisms in the literature. We test the code by comparing it to full simulations of two popular modified gravity models, namely f(R) gravity and nDGP, and find good agreement in the modified gravity boost-factors relative to ΛCDM even when using a fairly small number of COLA time steps.

Effect of cervical cancer education and provider recommendation for screening on screening rates: A systematic review and meta-analysis

PubMed Central

Achenbach, Chad J.; O’Dwyer, Linda C.; Evans, Charlesnika T.; McHugh, Megan; Hou, Lifang; Simon, Melissa A.; Murphy, Robert L.; Jordan, Neil

2017-01-01

Background Although cervical cancer is largely preventable through screening, detection and treatment of precancerous abnormalities, it remains one of the top causes of cancer-related morbidity and mortality globally. Objectives The objective of this systematic review is to understand the evidence of the effect of cervical cancer education compared to control conditions on cervical cancer screening rates in eligible women population at risk of cervical cancer. We also sought to understand the effect of provider recommendations for screening to eligible women on cervical cancer screening (CCS) rates compared to control conditions in eligible women population at risk of cervical cancer. Methods We used the PICO (Problem or Population, Interventions, Comparison and Outcome) framework as described in the Cochrane Collaboration Handbook to develop our search strategy. The details of our search strategy has been described in our systematic review protocol published in the International Prospective Register of systematic reviews (PROSPERO). The protocol registration number is CRD42016045605 available at: http://www.crd.york.ac.uk/prospero/display_record.asp?src=trip&ID=CRD42016045605. The search string was used in Pubmed, Embase, Cochrane Systematic Reviews and Cochrane CENTRAL register of controlled trials to retrieve study reports that were screened for inclusion in this review. Our data synthesis and reporting was guided by the Preferred Reporting Items for Systematic Reviews and Meta-analysis (PRISMA). We did a qualitative synthesis of evidence and, where appropriate, individual study effects were pooled in meta-analyses using RevMan 5.3 Review Manager. The Higgins I2 was used to assess for heterogeneity in studies pooled together for overall summary effects. We did assessment of risk of bias of individual studies included and assessed risk of publication bias across studies pooled together in meta-analysis by Funnel plot. Results Out of 3072 study reports screened, 28 articles were found to be eligible for inclusion in qualitative synthesis (5 of which were included in meta-analysis of educational interventions and 8 combined in meta-analysis of HPV self-sampling interventions), while 45 were excluded for various reasons. The use of theory-based educational interventions significantly increased CCS rates by more than double (OR, 2.46, 95% CI: 1.88, 3.21). Additionally, offering women the option of self-sampling for Human Papillomavirus (HPV) testing increased CCS rates by nearly 2-fold (OR = 1.71, 95% CI: 1.32, 2.22). We also found that invitation letters alone (or with a follow up phone contact), making an appointment, and sending reminders to patients who are due or overdue for screening had a significant effect on improving participation and CCS rates in populations at risk. Conclusion Our findings supports the implementation of theory-based cervical cancer educational interventions to increase women’s participation in cervical cancer screening programs, particularly when targeting communities with low literacy levels. Additionally, cervical cancer screening programs should consider the option of offering women the opportunity for self-sample collection particularly when such women have not responded to previous screening invitation or reminder letters for Pap smear collection as a method of screening. PMID:28873092

Effect of cervical cancer education and provider recommendation for screening on screening rates: A systematic review and meta-analysis.

PubMed

Musa, Jonah; Achenbach, Chad J; O'Dwyer, Linda C; Evans, Charlesnika T; McHugh, Megan; Hou, Lifang; Simon, Melissa A; Murphy, Robert L; Jordan, Neil

2017-01-01

Although cervical cancer is largely preventable through screening, detection and treatment of precancerous abnormalities, it remains one of the top causes of cancer-related morbidity and mortality globally. The objective of this systematic review is to understand the evidence of the effect of cervical cancer education compared to control conditions on cervical cancer screening rates in eligible women population at risk of cervical cancer. We also sought to understand the effect of provider recommendations for screening to eligible women on cervical cancer screening (CCS) rates compared to control conditions in eligible women population at risk of cervical cancer. We used the PICO (Problem or Population, Interventions, Comparison and Outcome) framework as described in the Cochrane Collaboration Handbook to develop our search strategy. The details of our search strategy has been described in our systematic review protocol published in the International Prospective Register of systematic reviews (PROSPERO). The protocol registration number is CRD42016045605 available at: http://www.crd.york.ac.uk/prospero/display_record.asp?src=trip&ID=CRD42016045605. The search string was used in Pubmed, Embase, Cochrane Systematic Reviews and Cochrane CENTRAL register of controlled trials to retrieve study reports that were screened for inclusion in this review. Our data synthesis and reporting was guided by the Preferred Reporting Items for Systematic Reviews and Meta-analysis (PRISMA). We did a qualitative synthesis of evidence and, where appropriate, individual study effects were pooled in meta-analyses using RevMan 5.3 Review Manager. The Higgins I2 was used to assess for heterogeneity in studies pooled together for overall summary effects. We did assessment of risk of bias of individual studies included and assessed risk of publication bias across studies pooled together in meta-analysis by Funnel plot. Out of 3072 study reports screened, 28 articles were found to be eligible for inclusion in qualitative synthesis (5 of which were included in meta-analysis of educational interventions and 8 combined in meta-analysis of HPV self-sampling interventions), while 45 were excluded for various reasons. The use of theory-based educational interventions significantly increased CCS rates by more than double (OR, 2.46, 95% CI: 1.88, 3.21). Additionally, offering women the option of self-sampling for Human Papillomavirus (HPV) testing increased CCS rates by nearly 2-fold (OR = 1.71, 95% CI: 1.32, 2.22). We also found that invitation letters alone (or with a follow up phone contact), making an appointment, and sending reminders to patients who are due or overdue for screening had a significant effect on improving participation and CCS rates in populations at risk. Our findings supports the implementation of theory-based cervical cancer educational interventions to increase women's participation in cervical cancer screening programs, particularly when targeting communities with low literacy levels. Additionally, cervical cancer screening programs should consider the option of offering women the opportunity for self-sample collection particularly when such women have not responded to previous screening invitation or reminder letters for Pap smear collection as a method of screening.

Modeling and prediction of ionospheric scintillation

NASA Technical Reports Server (NTRS)

Fremouw, E. J.

1974-01-01

Scintillation modeling performed thus far is based on the theory of diffraction by a weakly modulating phase screen developed by Briggs and Parkin (1963). Shortcomings of the existing empirical model for the scintillation index are discussed together with questions of channel modeling, giving attention to the needs of the communication engineers. It is pointed out that much improved scintillation index models may be available in a matter of a year or so.

Influence of a screening navigation program on social inequalities in health beliefs about colorectal cancer screening.

PubMed

Vallet, Fanny; Guillaume, Elodie; Dejardin, Olivier; Guittet, Lydia; Bouvier, Véronique; Mignon, Astrid; Berchi, Célia; Salinas, Agnès; Launoy, Guy; Christophe, Véronique

2016-08-01

The aim of the study was to test whether a screening navigation program leads to more favorable health beliefs and decreases social inequalities in them. The selected 261 noncompliant participants in a screening navigation versus a usual screening program arm had to respond to health belief measures inspired by the Protection Motivation Theory. Regression analyses showed that social inequalities in perceived efficacy of screening, favorable attitude, and perceived facility were reduced in the screening navigation compared to the usual screening program. These results highlight the importance of health beliefs to understand the mechanism of screening navigation programs in reducing social inequalities. © The Author(s) 2014.

Beyond Access and Exposure: Implications of Sneaky Media Use for Preschoolers' Sleep Behavior.

PubMed

Moorman, Jessica D; Harrison, Kristen

2018-01-09

Greater consumption of and access to screen media are known correlates of unhealthy sleep behavior in preschoolers. What remains unknown, however, is the role a child's media use plays in this association. Parents and guardians of U.S. preschoolers (N = 278, average child age 56 months) provided information about their child's nightly duration of sleep, daily duration of nap, quantity of screen media use, sneaky media use, and the presence of a screen media device in the bedroom. We assessed four media: television, DVD/VCRs, video games, and computer/Internet. Based on rationales of sleep displacement, the forbidden fruit hypothesis, and social cognitive theory, we predicted that increased consumption of and access to media, along with sneaky media use, would predict a shorter duration of nightly sleep and longer duration of daily nap across the four screen media. In correlational analyses, a clear pattern emerged with quantity of media use, screen media in the bedroom, and sneaky media use associated with shorter nightly duration of sleep and longer duration of daily nap. In regression analyses, only weekday evening television viewing and sneaky media use predicted shorter nightly sleep duration; weekend morning and evening DVD use predicted longer naps.

Rival Theories of Newsreading in the Electronic Newspaper Arena.

ERIC Educational Resources Information Center

Dozier, David M.

Emerging videotex news services--systems for distributing textual information on television screens that permit direct competition with pulp newspapers--are presently rooted in a limited theory of newsreading. The first of two rival theories of newsreading applicable to electronic newspapers is "uses and gratifications" research--the…

Increasing Cervical Cancer Screening Among US Hispanics/Latinas: A Qualitative Systematic Review

PubMed Central

Mann, Lilli; Foley, Kristie L.; Tanner, Amanda E.; Sun, Christina J.; Rhodes, Scott D.

2014-01-01

Purpose Hispanic/Latina women experience the highest cervical cancer incidence rates of any racial/ethnic group in the United States (US), and tend to present with more severe cases and experience higher mortality compared to most other populations. The goal of this qualitative systematic review was to explore existing interventions to increase cervical cancer screening among US Hispanics/Latinas and to identify characteristics of effective interventions and research gaps. Materials and Methods Six online databases were searched from their inception through June 30, 2013, using designated search terms and keywords. Peer-reviewed articles that documented an intervention designed to improve screening for cervical cancer among Hispanics/Latinas ages 18 years and older living in the US were reviewed. Data were abstracted using a standardized form to document intervention characteristics and results. Results Forty-five articles, describing 32 unique interventions, met inclusion criteria. Identified interventions consisted primarily of educational programs and/or provision of screening. Interventions used lay health advisors (LHAs), clinic-based outreach/delivery strategies, partnerships with churches, and mass media campaigns. Twelve interventions resulted in significant increases in cervical cancer screening rates. Conclusions Interventions developed utilizing theory, applying community-based participatory research approaches, and using lay health advisors were identified as having the greatest potential for improving cervical cancer screening among Hispanics/Latinas. There continues to be a need for the development of interventions in geographic areas with new and emerging Hispanic/Latino populations and that are comprehensive, follow participants for longer periods of time, and broaden the roles and build the capacities of LHAs. PMID:25154515

Breast cancer screening practices among first-generation immigrant muslim women.

PubMed

Hasnain, Memoona; Menon, Usha; Ferrans, Carol Estwing; Szalacha, Laura

2014-07-01

The purpose of this study was to identify beliefs about breast cancer, screening practices, and factors associated with mammography use among first-generation immigrant Muslim women in Chicago, IL. A convenience sample of 207 first-generation immigrant Muslim women (Middle Eastern 51%; South Asian 49%) completed a culturally adapted questionnaire developed from established instruments. The questionnaire was administered in Urdu, Hindi, Arabic, or English, based on participant preference. Internal-consistency reliability was demonstrated for all scales (alpha coefficients ranged from 0.64 to 0.91). Associations between enabling, predisposing, and need variables and the primary outcome of mammography use were explored by fitting logistic regression models. Although 70% of the women reported having had a mammogram at least once, only 52% had had one within the past 2 years. Four factors were significant predictors of ever having had a mammogram: years in the United States, self-efficacy, perceived importance of mammography, and intent to be screened. Five factors were significant predictors of adherence (having had a mammogram in the past 2 years): years in the United States, having a primary care provider, perceived importance of mammography, barriers, and intent to be screened. This article sheds light on current screening practices and identifies theory-based constructs that facilitate and hinder Muslim women's participation in mammography screening. Our findings provide insights for reaching out particularly to new immigrants, developing patient education programs grounded in culturally appropriate approaches to address perceived barriers and building women's self-efficacy, as well as systems-level considerations for ensuring access to primary care providers.

Psychologist in a pocket: towards depression screening on mobile phones.

PubMed

Bitsch, Jó Ágila; Ramos, Roann; Ix, Tim; Ferrer-Cheng, Paula Glenda; Wehrle, Klaus

2015-01-01

Depression is the most prevalent clinical disorder and one of the main causes of disability. This makes early detection of depressive symptoms critical in its prevention and management. This paper presents and discusses the development of Psychologist in a Pocket (PiaP), a mental mHealth application for Android which screens and monitors for these symptoms, and-given the explicit permission of the user-alerts a trusted contact such as the mental health professional or a close friend, if it detects symptoms. All text inputted electronically-such as short message services, emails, social network posts-is analyzed based on keywords related to depression based on DSM-5 and ICD criteria as well as Beck's Cognitive Theory of Depression and the Self-Focus Model. Data evaluation and collection happen in the background, on-device, without requiring any user involvement. Currently, the application is in an early prototype phase entering initial clinical validation.

Parameter screening: the use of a dummy parameter to identify non-influential parameters in a global sensitivity analysis

NASA Astrophysics Data System (ADS)

Khorashadi Zadeh, Farkhondeh; Nossent, Jiri; van Griensven, Ann; Bauwens, Willy

2017-04-01

Parameter estimation is a major concern in hydrological modeling, which may limit the use of complex simulators with a large number of parameters. To support the selection of parameters to include in or exclude from the calibration process, Global Sensitivity Analysis (GSA) is widely applied in modeling practices. Based on the results of GSA, the influential and the non-influential parameters are identified (i.e. parameters screening). Nevertheless, the choice of the screening threshold below which parameters are considered non-influential is a critical issue, which has recently received more attention in GSA literature. In theory, the sensitivity index of a non-influential parameter has a value of zero. However, since numerical approximations, rather than analytical solutions, are utilized in GSA methods to calculate the sensitivity indices, small but non-zero indices may be obtained for the indices of non-influential parameters. In order to assess the threshold that identifies non-influential parameters in GSA methods, we propose to calculate the sensitivity index of a "dummy parameter". This dummy parameter has no influence on the model output, but will have a non-zero sensitivity index, representing the error due to the numerical approximation. Hence, the parameters whose indices are above the sensitivity index of the dummy parameter can be classified as influential, whereas the parameters whose indices are below this index are within the range of the numerical error and should be considered as non-influential. To demonstrated the effectiveness of the proposed "dummy parameter approach", 26 parameters of a Soil and Water Assessment Tool (SWAT) model are selected to be analyzed and screened, using the variance-based Sobol' and moment-independent PAWN methods. The sensitivity index of the dummy parameter is calculated from sampled data, without changing the model equations. Moreover, the calculation does not even require additional model evaluations for the Sobol' method. A formal statistical test validates these parameter screening results. Based on the dummy parameter screening, 11 model parameters are identified as influential. Therefore, it can be denoted that the "dummy parameter approach" can facilitate the parameter screening process and provide guidance for GSA users to define a screening-threshold, with only limited additional resources. Key words: Parameter screening, Global sensitivity analysis, Dummy parameter, Variance-based method, Moment-independent method

Guided design of copper oxysulfide superconductors

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

Yee, Chuck-Hou; Birol, Turan; Kotliar, Gabriel

2015-07-01

We describe a framework for designing novel materials, combining modern first-principles electronic-structure tools, materials databases, and evolutionary algorithms capable of exploring large configurational spaces. Guided by the chemical principles introduced by Antipov et al., for the design and synthesis of the Hg-based high-temperature superconductors, we apply our framework to screen 333 proposed compositions to design a new layered copper oxysulfide, Hg(CaS)2CuO2. We evaluate the prospects of superconductivity in this oxysulfide using theories based on charge-transfer energies, orbital distillation and uniaxial strain.

Carbonic anhydrase inhibition of Schiff base derivative of imino-methyl-naphthalen-2-ol: Synthesis, structure elucidation, molecular docking, dynamic simulation and density functional theory calculations

NASA Astrophysics Data System (ADS)

Abbas, Saghir; Nasir, Hafiza Huma; Zaib, Sumera; Ali, Saqib; Mahmood, Tariq; Ayub, Khurshid; Tahir, Muhammad Nawaz; Iqbal, Jamshed

2018-03-01

In the present study, we have designed and synthesized a Schiff base derivative 3 and characterized by FT-IR, 1H and 13C NMR spectroscopy. Single crystal X-ray diffraction and NMR studies were also performed. The synthetic compound was screened for its inhibitory potential against carbonic anhydrase II. The experimental results were validated by molecular docking and dynamic simulations of compound 3 in the active pocket of enzyme. Important binding interactions with the key residues in the active site of the carbonic anhydrase enzyme were revealed. Moreover, supramolecular assembly of the title compound was analyzed by density functional theory (DFT) calculations. These studies rendered a more clear understanding for the demonstration of novel molecular mechanism involved in CA II inhibition by the synthesized compound.

Applicability of Kerker preconditioning scheme to the self-consistent density functional theory calculations of inhomogeneous systems

NASA Astrophysics Data System (ADS)

Zhou, Yuzhi; Wang, Han; Liu, Yu; Gao, Xingyu; Song, Haifeng

2018-03-01

The Kerker preconditioner, based on the dielectric function of homogeneous electron gas, is designed to accelerate the self-consistent field (SCF) iteration in the density functional theory calculations. However, a question still remains regarding its applicability to the inhomogeneous systems. We develop a modified Kerker preconditioning scheme which captures the long-range screening behavior of inhomogeneous systems and thus improves the SCF convergence. The effectiveness and efficiency is shown by the tests on long-z slabs of metals, insulators, and metal-insulator contacts. For situations without a priori knowledge of the system, we design the a posteriori indicator to monitor if the preconditioner has suppressed charge sloshing during the iterations. Based on the a posteriori indicator, we demonstrate two schemes of the self-adaptive configuration for the SCF iteration.

Role of Psychosocial Factors and Health Literacy in Pregnant Women’s Intention to Use a Decision Aid for Down Syndrome Screening: A Theory-Based Web Survey

PubMed Central

Delanoë, Agathe; Lépine, Johanie; Turcotte, Stéphane; Leiva Portocarrero, Maria Esther; Robitaille, Hubert; Giguère, Anik MC; Wilson, Brenda J; Witteman, Holly O; Lévesque, Isabelle; Guillaumie, Laurence

2016-01-01

Background Deciding about undergoing prenatal screening is difficult, as it entails risks, potential loss and regrets, and challenges to personal values. Shared decision making and decision aids (DAs) can help pregnant women give informed and values-based consent or refusal to prenatal screening, but little is known about factors influencing the use of DAs. Objective The objective of this study was to identify the influence of psychosocial factors on pregnant women’s intention to use a DA for prenatal screening for Down syndrome (DS). We also added health literacy variables to explore their influence on pregnant women’s intention. Methods We conducted a survey of pregnant women in the province of Quebec (Canada) using a Web panel. Eligibility criteria included age >18 years, >16 weeks pregnant, low-risk pregnancy, and having decided about prenatal screening for the current pregnancy. We collected data based on an extended version of the Theory of Planned Behavior assessing 7 psychosocial constructs (intention, attitude, anticipated regret, subjective norm, descriptive norm, moral norm, and perceived control), 3 related sets of beliefs (behavioral, normative, and control beliefs), 4 health literacy variables, and sociodemographics. Eligible women watched a video depicting the behavior of interest before completing a Web-based questionnaire. We performed descriptive, bivariate, and ordinal logistic regression analyses. Results Of the 383 eligible pregnant women who agreed to participate, 350 pregnant women completed the Web-based questionnaire and 346 were retained for analysis (completion rate 350/383, 91.4%; mean age 30.1, SD 4.3, years). In order of importance, factors influencing intention to use a DA for prenatal screening for DS were attitude (odds ratio, OR, 9.16, 95% CI 4.02-20.85), moral norm (OR 7.97, 95% CI 4.49-14.14), descriptive norm (OR 2.83, 95% CI 1.63-4.92), and anticipated regret (OR 2.43, 95% CI 1.71-3.46). Specific attitudinal beliefs significantly related to intention were that using a DA would reassure them (OR 2.55, 95% CI 1.73-4.01), facilitate their reflections with their spouse (OR 1.55, 95% CI 1.05-2.29), and let them know about the advantages of doing or not doing the test (OR 1.53, 95% CI 1.05-2.24). Health literacy did not add to the predictive power of our model (P values range .43-.92). Conclusions Implementation interventions targeting the use of a DA for prenatal screening for DS by pregnant women should address a number of modifiable factors, especially by introducing the advantages of using the DA (attitude), informing pregnant women that they might regret not using it (anticipated regret), and presenting the use of DAs as a common practice (descriptive norm). However, interventions on moral norms related to the use of DA should be treated with caution. Further studies that include populations with low health literacy are needed before decisive claims can be made. PMID:27793792

Neoclassical and Institutional Economics as Foundations for Human Resource Development Theory

ERIC Educational Resources Information Center

Wang, Greg G.; Holton, Elwood F., III

2005-01-01

In an effort to more comprehensively understand economics as a foundation of human resource development (HRD), this article reviews economic theories and models pertinent to HRD research and theory building. By examining neoclassical and neoinstitutional schools of contemporary economics, especially the screening model and the internal labor…

Analysis of Current DNA Encoded Library Screening Data Indicates Higher False Negative Rates for Numerically Larger Libraries.

PubMed

Satz, Alexander L; Hochstrasser, Remo; Petersen, Ann C

2017-04-10

To optimize future DNA-encoded library design, we have attempted to quantify the library size at which the signal becomes undetectable. To accomplish this we (i) have calculated that percent yields of individual library members following a screen range from 0.002 to 1%, (ii) extrapolated that ∼1 million copies per library member are required at the outset of a screen, and (iii) from this extrapolation predict that false negative rates will begin to outweigh the benefit of increased diversity at library sizes >10 8 . The above analysis is based upon a large internal data set comprising multiple screens, targets, and libraries; we also augmented our internal data with all currently available literature data. In theory, high false negative rates may be overcome by employing larger amounts of library; however, we argue that using more than currently reported amounts of library (≫10 nmoles) is impractical. The above conclusions may be generally applicable to other DNA encoded library platforms, particularly those platforms that do not allow for library amplification.

Yield and failure criteria for composite materials under static and dynamic loading

DOE PAGES

Daniel, Isaac M.

2015-12-23

To facilitate and accelerate the process of introducing, evaluating and adopting of new material systems, it is important to develop/establish comprehensive and effective procedures of characterization, modeling and failure prediction of structural laminates based on the properties of the constituent materials, e. g., fibers, matrix, and the single ply or lamina. A new failure theory, the Northwestern (NU-Daniel) theory, has been proposed for predicting lamina yielding and failure under multi-axial states of stress including strain rate effects. It is primarily applicable to matrix-dominated interfiber/interlaminar failures. It is based on micromechanical failure mechanisms but is expressed in terms of easily measuredmore » macroscopic lamina stiffness and strength properties. It is presented in the form of a master failure envelope incorporating strain rate effects. The theory was further adapted and extended to the prediction of in situ first ply yielding and failure (FPY and FPF) and progressive failure of multi-directional laminates under static and dynamic loadings. The significance of this theory is that it allows for rapid screening of new composite materials without very extensive testing and offers easily implemented design tools.« less

The effect of a healthy lifestyle programme on 8-9 year olds from social disadvantage.

PubMed

Breslin, Gavin; Brennan, Deirdre; Rafferty, Ruth; Gallagher, Alison M; Hanna, Donncha

2012-07-01

This study assessed the efficacy of a school-based healthy lifestyle intervention (Sport for LIFE) for increasing physical activity, decreasing sedentary behaviour, reducing screen time behaviour, encouraging healthy attitudes and behaviour to nutrition, and reducing body mass index (BMI) in 8-9-year-old primary school children from lower socioeconomic backgrounds in Northern Ireland. A non-randomised controlled trial of 416 children from 24 schools took part. Schools were randomly assigned to one of two groups, an intervention or control group with 12 schools in each group. The intervention group received a 12-week school-based programme based on social cognitive theory. At baseline and follow-up, groups completed questionnaires assessing physical activity, screen time behaviour and dietary patterns. On each occasion anthropometric assessments of height and weight were taken. Physical activity and sedentary behaviour were measured by accelerometry. Significant effects were observed for vigorous, moderate and light activity for the intervention group at follow-up. Sedentary behaviour was significantly reduced for the intervention group but not for the control group. No significant effects of the intervention on BMI, screen time behaviour or attitudes to nutrition, with the exception of non-core foods, were shown. The programme was effective in increasing physical activity and reducing sedentary behaviour, however no significant changes in screen time behaviour and attitude to nutrition, with the exception of non-core foods, were observed. Future research ideas are offered for tackling low levels of physical activity in children.

Validation of a condition-specific measure for women having an abnormal screening mammography.

PubMed

Brodersen, John; Thorsen, Hanne; Kreiner, Svend

2007-01-01

The aim of this study is to assess the validity of a new condition-specific instrument measuring psychosocial consequences of abnormal screening mammography (PCQ-DK33). The draft version of the PCQ-DK33 was completed on two occasions by 184 women who had received an abnormal screening mammography and on one occasion by 240 women who had received a normal screening result. Item Response Theories and Classical Test Theories were used to analyze data. Construct validity, concurrent validity, known group validity, objectivity and reliability were established by item analysis examining the fit between item responses and Rasch models. Six dimensions covering anxiety, behavioral impact, sense of dejection, impact on sleep, breast examination, and sexuality were identified. One item belonging to the dejection dimension had uniform differential item functioning. Two items not fitting the Rasch models were retained because of high face validity. A sick leave item added useful information when measuring side effects and socioeconomic consequences of breast cancer screening. Five "poor items" were identified and should be deleted from the final instrument. Preliminary evidence for a valid and reliable condition-specific measure for women having an abnormal screening mammography was established. The measure includes 27 "good" items measuring different attributes of the same overall latent structure-the psychosocial consequences of abnormal screening mammography.

Internal models of target motion: expected dynamics overrides measured kinematics in timing manual interceptions.

PubMed

Zago, Myrka; Bosco, Gianfranco; Maffei, Vincenzo; Iosa, Marco; Ivanenko, Yuri P; Lacquaniti, Francesco

2004-04-01

Prevailing views on how we time the interception of a moving object assume that the visual inputs are informationally sufficient to estimate the time-to-contact from the object's kinematics. Here we present evidence in favor of a different view: the brain makes the best estimate about target motion based on measured kinematics and an a priori guess about the causes of motion. According to this theory, a predictive model is used to extrapolate time-to-contact from expected dynamics (kinetics). We projected a virtual target moving vertically downward on a wide screen with different randomized laws of motion. In the first series of experiments, subjects were asked to intercept this target by punching a real ball that fell hidden behind the screen and arrived in synchrony with the visual target. Subjects systematically timed their motor responses consistent with the assumption of gravity effects on an object's mass, even when the visual target did not accelerate. With training, the gravity model was not switched off but adapted to nonaccelerating targets by shifting the time of motor activation. In the second series of experiments, there was no real ball falling behind the screen. Instead the subjects were required to intercept the visual target by clicking a mousebutton. In this case, subjects timed their responses consistent with the assumption of uniform motion in the absence of forces, even when the target actually accelerated. Overall, the results are in accord with the theory that motor responses evoked by visual kinematics are modulated by a prior of the target dynamics. The prior appears surprisingly resistant to modifications based on performance errors.

Psychometric properties of the Brazilian-adapted version of the Ages and Stages Questionnaire in public child daycare centers.

PubMed

Filgueiras, Alberto; Pires, Pedro; Maissonette, Silvia; Landeira-Fernandez, J

2013-08-01

Well-designed screening assessment instruments that can evaluate child development in public daycare centers represent an important resource to help improve the quality of these programs, as an early detection method for early developmental delay. The Ages and Stages Questionnaire, 3rd edition (ASQ-3), comprises a series of 21 questionnaires designed to screen developmental performance in the domains of communication, gross motor skills, fine motor skills, problem solving, and personal-social ability in children aged 2 to 66 months. The purpose of the present work was to translate and adapt all of the ASQ-3 questionnaires for use in Brazilian public child daycare centers and to explore their psychometric characteristics with both Classical Test Theory and Rating Scale analyses from the Rasch model family. A total of 18 Ages & Stages Questionnaires - Brazilian translation (ASQ-BR) questionnaires administered at intervals from 6 to 60 months of age were analyzed based on primary caregiver evaluations of 45,640 children distributed in 468 public daycare centers in the city of Rio de Janeiro. The results indicated that most of the ASQ-BR questionnaires had adequate internal consistency. Exploratory factor analyses yielded a one-factor solution for each domain of all of the ASQ-BR questionnaires. The only exception was the personal-social domain in some of the questionnaires. Item Response Theory based on Rating Scale analysis (infit and outfit mean squares statistics) indicated that only 44 of 540 items showed misfit problems. In summary, the ASQ-BR questionnaires are psychometrically sound developmental screening instruments that can be easily administered by primary caregivers. Copyright © 2013 Elsevier Ltd. All rights reserved.

Rationale and study protocol for the 'active teen leaders avoiding screen-time' (ATLAS) group randomized controlled trial: an obesity prevention intervention for adolescent boys from schools in low-income communities.

PubMed

Smith, Jordan J; Morgan, Philip J; Plotnikoff, Ronald C; Dally, Kerry A; Salmon, Jo; Okely, Anthony D; Finn, Tara L; Babic, Mark J; Skinner, Geoff; Lubans, David R

2014-01-01

The negative consequences of unhealthy weight gain and the high likelihood of pediatric obesity tracking into adulthood highlight the importance of targeting youth who are 'at risk' of obesity. The aim of this paper is to report the rationale and study protocol for the 'Active Teen Leaders Avoiding Screen-time' (ATLAS) obesity prevention intervention for adolescent boys living in low-income communities. The ATLAS intervention will be evaluated using a cluster randomized controlled trial in 14 secondary schools in the state of New South Wales (NSW), Australia (2012 to 2014). ATLAS is an 8-month multi-component, school-based program informed by self-determination theory and social cognitive theory. The intervention consists of teacher professional development, enhanced school-sport sessions, researcher-led seminars, lunch-time physical activity mentoring sessions, pedometers for self-monitoring, provision of equipment to schools, parental newsletters, and a smartphone application and website. Assessments were conducted at baseline and will be completed again at 9- and 18-months from baseline. Primary outcomes are body mass index (BMI) and waist circumference. Secondary outcomes include BMI z-scores, body fat (bioelectrical impedance analysis), physical activity (accelerometers), muscular fitness (grip strength and push-ups), screen-time, sugar-sweetened beverage consumption, resistance training skill competency, daytime sleepiness, subjective well-being, physical self-perception, pathological video gaming, and aggression. Hypothesized mediators of behavior change will also be explored. ATLAS is an innovative school-based intervention designed to improve the health behaviors and related outcomes of adolescent males in low-income communities. Copyright © 2013 Elsevier Inc. All rights reserved.

Theories and measures of elder abuse.

PubMed

Abolfathi Momtaz, Yadollah; Hamid, Tengku Aizan; Ibrahim, Rahimah

2013-09-01

Elder abuse is a pervasive phenomenon around the world with devastating effects on the victims. Although it is not a new phenomenon, interest in examining elder abuse is relatively new. This paper aims to provide an overview of the aetiological theories and measures of elder abuse. The paper briefly reviews theories to explain causes of elder abuse and then discusses the most commonly used measures of elder abuse. Based on the reviewed theories, it can be concluded that elder abuse is a multifactorial problem that may affect elderly people from different backgrounds and involve a wide variety of potential perpetrators, including caregivers, adult children, and partners. The review of existing measurement instruments notes that many different screening and assessment instruments have been developed to identify elders who are at risk for or are victims of abuse. However, there is a real need for more measurements of elder abuse, as the current instruments are limited in scope. © 2013 The Authors. Psychogeriatrics © 2013 Japanese Psychogeriatric Society.

Enhanced maternal and child health nurse care for women experiencing intimate partner/family violence: protocol for MOVE, a cluster randomised trial of screening and referral in primary health care

PubMed Central

2012-01-01

Background Intimate partner violence (IPV) can result in significant harm to women and families and is especially prevalent when women are pregnant or recent mothers. Maternal and child health nurses (MCHN) in Victoria, Australia are community-based nurse/midwives who see over 95% of all mothers with newborns. MCHN are in an ideal position to identify and support women experiencing IPV, or refer them to specialist family violence services. Evidence for IPV screening in primary health care is inconclusive to date. The Victorian government recently required nurses to screen all mothers when babies are four weeks old, offering an opportunity to examine the effectiveness of MCHN IPV screening practices. This protocol describes the development and design of MOVE, a study to examine IPV screening effectiveness and the sustainability of screening practice. Methods/design MOVE is a cluster randomised trial of a good practice model of MCHN IPV screening involving eight maternal and child health nurse teams in Melbourne, Victoria. Normalisation Process Theory (NPT) was incorporated into the design, implementation and evaluation of the MOVE trial to enhance and evaluate sustainability. Using NPT, the development stage combined participatory action research with intervention nurse teams and a systematic review of nurse IPV studies to develop an intervention model incorporating consensus guidelines, clinical pathway and strategies for individual nurses, their teams and family violence services. Following twelve months’ implementation, primary outcomes assessed include IPV inquiry, IPV disclosure by women and referral using data from MCHN routine data collection and a survey to all women giving birth in the previous eight months. IPV will be measured using the Composite Abuse Scale. Process and impact evaluation data (online surveys and key stakeholders interviews) will highlight NPT concepts to enhance sustainability of IPV identification and referral. Data will be collected again in two years. Discussion MOVE will be the first randomised trial to determine IPV screening effectiveness in a community based nurse setting and the first to examine sustainability of an IPV screening intervention. It will further inform the debate about the effectiveness of IPV screening and describe IPV prevalence in a community based post-partum and early infant population. Trial registration ACTRN12609000424202 PMID:22994910

Consequences of screening in lung cancer: development and dimensionality of a questionnaire.

PubMed

Brodersen, John; Thorsen, Hanne; Kreiner, Svend

2010-08-01

The objective of this study was to extend the Consequences of Screening (COS) Questionnaire for use in a lung cancer screening by testing for comprehension, content coverage, dimensionality, and reliability. In interviews, the suitability, content coverage, and relevance of the COS were tested on participants in a lung cancer screening program. The results were thematically analyzed to identify the key consequences of abnormal and false-positive screening results. Item Response Theory and Classical Test Theory were used to analyze data. Dimensionality, objectivity, and reliability were established by item analysis, examining the fit between item responses and Rasch models. Eight themes specifically relevant for participants in lung cancer screening results were identified: "self-blame,"focus on symptoms,"stigmatization,"introvert,"harm of smoking,"impulsivity,"empathy," and "regretful of still smoking." Altogether, 26 new items for part I and 16 new items for part II were generated. These themes were confirmed to fit a partial-credit Rasch model measuring different constructs including several of the new items. In conclusion, the reliability and the dimensionality of a condition-specific measure with high content validity for persons having abnormal or false-positive lung cancer screening results have been demonstrated. This new questionnaire called Consequences of Screening in Lung Cancer (COS-LC) covers in two parts the psychosocial experience in lung cancer screening. Part I: "anxiety,"behavior,"dejection,"sleep,"self-blame,"focus on airway symptoms,"stigmatization,"introvert," and "harm of smoking." Part II: "calm/relax,"social network,"existential values,"impulsivity,"empathy," and "regretful of still smoking."

Economic game theory for mutualism and cooperation.

PubMed

Archetti, Marco; Scheuring, István; Hoffman, Moshe; Frederickson, Megan E; Pierce, Naomi E; Yu, Douglas W

2011-12-01

We review recent work at the interface of economic game theory and evolutionary biology that provides new insights into the evolution of partner choice, host sanctions, partner fidelity feedback and public goods. (1) The theory of games with asymmetrical information shows that the right incentives allow hosts to screen-out parasites and screen-in mutualists, explaining successful partner choice in the absence of signalling. Applications range from ant-plants to microbiomes. (2) Contract theory distinguishes two longstanding but weakly differentiated explanations of host response to defectors: host sanctions and partner fidelity feedback. Host traits that selectively punish misbehaving symbionts are parsimoniously interpreted as pre-adaptations. Yucca-moth and legume-rhizobia mutualisms are argued to be examples of partner fidelity feedback. (3) The theory of public goods shows that cooperation in multi-player interactions can evolve in the absence of assortment, in one-shot social dilemmas among non-kin. Applications include alarm calls in vertebrates and exoenzymes in microbes. 2011 Blackwell Publishing Ltd/CNRS.

Behavioral Theory and Culture Special Issue: Authors' Response to Commentaries

ERIC Educational Resources Information Center

Pasick, Rena J.; Burke, Nancy J.; Joseph, Galen

2009-01-01

This article presents the authors' response to commentaries that focus on the "Behavioral Constructs and Culture in Cancer Screening" (3Cs) study. The 3Cs study had an unremarkable beginning, with two colleagues discussing their frustration over the narrow range of behavioral theories and the limited guidance the theories offered for a study…

Evaluation of Quantitative Environmental Stress Screening (ESS) Methods. Volume 1

DTIC Science & Technology

1991-11-01

required information on screening strength from the curvefitting parameters. The underlying theory and approach taken are discussed in Appendix A. To...in field 1020 arm St.,Vas AJ Ptr 0.4i Currpnt. c- ugt ~ing DU?/SYS 2.7264 Wll/IY.3 at Factory Stress- NaxiLMw outgoing W?is’ys 0.288 DrW/5?S at Field...182 125 K.W.Fertig and V.X. Murthy, Models for Reliability Growth During Burn-in: Theory and Applicat’ons,Proceedings 1978 Annual Reliability and

Doctors' perspectives on PSA testing illuminate established differences in prostate cancer screening rates between Australia and the UK: a qualitative study.

PubMed

Pickles, Kristen; Carter, Stacy M; Rychetnik, Lucie; Entwistle, Vikki A

2016-12-05

To examine how general practitioners (GPs) in the UK and GPs in Australia explain their prostate-specific antigen (PSA) testing practices and to illuminate how these explanations are similar and how they are different. A grounded theory study. Primary care practices in Australia and the UK. 69 GPs in Australia (n=40) and the UK (n=29). We included GPs of varying ages, sex, clinical experience and patient populations. All GPs interested in participating in the study were included. GPs' accounts revealed fundamental differences in whether and how prostate cancer screening occurred in their practice and in the broader context within which they operate. The history of prostate screening policy, organisational structures and funding models appeared to drive more prostate screening in Australia and less in the UK. In Australia, screening processes and decisions were mostly at the discretion of individual clinicians, and varied considerably, whereas the accounts of UK GPs clearly reflected a consistent, organisationally embedded approach based on local evidence-based recommendations to discourage screening. The GP accounts suggested that healthcare systems, including historical and current organisational and funding structures and rules, collectively contribute to how and why clinicians use the PSA test and play a significant role in creating the mindlines that GPs employ in their clinic. Australia's recently released consensus guidelines may support more streamlined and consistent care. However, if GP mindlines and thus routine practice in Australia are to shift, to ultimately reduce unnecessary or harmful prostate screening, it is likely that other important drivers at all levels of the screening process will need to be addressed. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.

Understanding Dyslexia in Children through Human Development Theories

PubMed Central

Al-Shidhani, Thuraya Ahmed; Arora, Vinita

2012-01-01

Dyslexia is a specific learning disability that is neurological in origin, with an estimated overall worldwide prevalence of 5–10% of the population. It is characterised by difficulties in reading, accuracy, fluency, spelling and decoding abilities. The majority of publications reviewed indicated that screening is performed at the preschool level. Screening can also be conducted at birth or the first year of life. Understanding human development theory, for example, Piaget’s human development theory, may help determine at which stage of childhood development dyslexia is more detectable, and therefore guide the management of this disability. The objective of this review is to provide a brief and updated overview of dyslexia and its management in children through human development issues. PMID:23269949

A Focus Group Assessment to Determine Motivations, Barriers and Effectiveness of a University-Based Worksite Wellness Program

PubMed Central

Hill-Mey, Patricia E.; Merrill, Ray M.; Kumpfer, Karol L.; Reel, Justine; Hyatt-Neville, Beverly

2013-01-01

Background: This study explores university employee perceptions and under­standing about its Worksite Health Promotion Program (WHPP). The WHPP included a Health Risk Appraisal (HRA), biometric screening, publicity for on-campus health programs and facilities, and health coaching. Methods: A qualitative design was used based on a grounded theory ap­proach. Four 90 minutes focus groups with 6-8 participants in each were conducted within a two 2 week period among employees, representing fac­ulty/participants, fac­ulty/nonparticipants, staff/participants, and staff/nonparticipants. Responses to questions about motivations, barriers, and perceived health benefits that impacted participation in the WHPP were digi­tally recorded, transcribed and coded for themes. Results: Incentives effectively motivated participation. Biometric screening had the largest impact on behavior change, followed by the information learned from the HRA. However, despite two-thirds of the employees partici­pating in the pro­gram, lack of a full understanding of WHPP benefits and services lowered partici­pation in follow-up services and supplemental pro­grams. Conclusions: Biometric screening and HRAs effectively motivate program par­ticipation. Communication of benefits and services are important when providing WHPPs. PMID:24688965

Part 2: Screening, Brief Intervention and Referral to Treatment Plus Recovery Management: A Proposed Model for Recovery-Oriented Primary Care.

PubMed

Fornili, Katherine S

2016-01-01

Part 1 of this two-part series (The Theoretical Basis for Recovery-Oriented Management of Substance Use Disorders in the Primary Care) explored the theoretical foundations for evidence-based substance Screening, Brief Intervention and Referral to Treatment (SBIRT) services. The aim was to produce possible explanations for why traditional SBIRT works well for individuals with unhealthy alcohol use but not as well for individuals who have more serious substance use disorders, including drug use and alcohol/drug dependence. Building on that analysis, through meaningful application of recovery management (RM) concepts within an integrated primary care/behavioral health context, a new, theory-based, recovery-oriented framework for primary care SBIRT is now introduced in Part 2. The proposed SBIRT Plus Recovery Management (SBIRT + RM) model moves traditional SBIRT from its original, limited, and narrow focus only on substance detection, brief intervention, and referral to its rightful, structured placement within a comprehensive, multidimensional, recovery-oriented system of care clinical practice environment. SBIRT+RM describes relevant strategies for improving recovery outcomes for individuals identified through primary care substance screening and defines primary care provider roles and responsibilities for sustained recovery support and long-term recovery maintenance.

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

Gratia, Pierre; Hu, Wayne; Enrico Fermi Institute and Kavli Institute for Cosmological Physics, University of Chicago,South Ellis Avenue, Chicago, IL 60637

Attempts to modify gravity in the infrared typically require a screening mechanism to ensure consistency with local tests of gravity. These screening mechanisms fit into three broad classes; we investigate theories which are capable of exhibiting more than one type of screening. Specifically, we focus on a simple model which exhibits both Vainshtein and kinetic screening. We point out that due to the two characteristic length scales in the problem, the type of screening that dominates depends on the mass of the sourcing object, allowing for different phenomenology at different scales. We consider embedding this double screening phenomenology in amore » broader cosmological scenario and show that the simplest examples that exhibit double screening are radiatively stable.« less

Literature Review of Cloud Based E-learning Adoption by Students: State of the Art and Direction for Future Work

NASA Astrophysics Data System (ADS)

Hassan Kayali, Mohammad; Safie, Nurhizam; Mukhtar, Muriati

2016-11-01

Cloud computing is a new paradigm shift in information technology. Most of the studies in the cloud are business related while the studies in cloud based e-learning are few. The field is still in its infancy and researchers have used several adoption theories to discover the dimensions of this field. The purpose of this paper is to review and integrate the literature to understand the current situation of the cloud based e-learning adoption. A total of 312 articles were extracted from Science direct, emerald, and IEEE. Screening processes were applied to select only the articles that are related to the cloud based e-learning. A total of 231 removed because they are related to business organization. Next, a total of 63 articles were removed because they are technical articles. A total of 18 articles were included in this paper. A frequency analysis was conducted on the paper to identify the most frequent factors, theories, statistical software, respondents, and countries of the studies. The findings showed that usefulness and ease of use are the most frequent factors. TAM is the most prevalent adoption theories in the literature. The mean of the respondents in the reviewed studies is 377 and Malaysia is the most researched countries in terms of cloud based e-learning. Studies of cloud based e-learning are few and more empirical studies are needed.

Factors influencing young men's decision to undergo health screening in Malaysia: a qualitative study.

PubMed

Teo, Chin Hai; Ng, Chirk Jenn; White, Alan

2017-03-10

Uptake of health screening is low in men, particularly among those aged <40 years. This study aimed to explore factors that influence health screening behaviour in younger men. This qualitative study employed an interpretive descriptive approach. Two trained researchers conducted in-depth interviews (IDIs) and focus group discussions (FGDs) using a semi-structured topic guide, which was developed based on literature review and behavioural theories. All IDIs and FGDs were audio-recorded and transcribed verbatim. Two researchers analysed the data independently using a thematic approach. Men working in a banking institution in Kuala Lumpur were recruited to the study. They were purposively sampled according to their ethnicity, job position, age and screening status in order to achieve maximal variation. Eight IDIs and five FGDs were conducted (n=31) and six themes emerged from the analysis. (1) Young men did not consider screening as part of prevention and had low risk perception. (2) The younger generation was more receptive to health screening due to their exposure to health information through the internet. (3) Health screening was not a priority in young men except for those who were married. (4) Young men had limited income and would rather invest in health insurance than screening. (5) Young men tended to follow doctors' advice when it comes to screening and preferred doctors of the same gender and ethnicity. (6) Medical overuse was also raised where young men wanted more screening tests while doctors tended to promote unnecessary screening tests to them. This study identified important factors that influenced young men's screening behaviour. Health authorities should address young men's misperceptions, promote the importance of early detection and develop a reasonable health screening strategy for them. Appropriate measures must be put in place to reduce low value screening practices. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.

Factors influencing young men's decision to undergo health screening in Malaysia: a qualitative study

PubMed Central

Teo, Chin Hai; Ng, Chirk Jenn; White, Alan

2017-01-01

Objectives Uptake of health screening is low in men, particularly among those aged <40 years. This study aimed to explore factors that influence health screening behaviour in younger men. Design This qualitative study employed an interpretive descriptive approach. Two trained researchers conducted in-depth interviews (IDIs) and focus group discussions (FGDs) using a semi-structured topic guide, which was developed based on literature review and behavioural theories. All IDIs and FGDs were audio-recorded and transcribed verbatim. Two researchers analysed the data independently using a thematic approach. Participants and setting Men working in a banking institution in Kuala Lumpur were recruited to the study. They were purposively sampled according to their ethnicity, job position, age and screening status in order to achieve maximal variation. Results Eight IDIs and five FGDs were conducted (n=31) and six themes emerged from the analysis. (1) Young men did not consider screening as part of prevention and had low risk perception. (2) The younger generation was more receptive to health screening due to their exposure to health information through the internet. (3) Health screening was not a priority in young men except for those who were married. (4) Young men had limited income and would rather invest in health insurance than screening. (5) Young men tended to follow doctors' advice when it comes to screening and preferred doctors of the same gender and ethnicity. (6) Medical overuse was also raised where young men wanted more screening tests while doctors tended to promote unnecessary screening tests to them. Conclusions This study identified important factors that influenced young men's screening behaviour. Health authorities should address young men's misperceptions, promote the importance of early detection and develop a reasonable health screening strategy for them. Appropriate measures must be put in place to reduce low value screening practices. PMID:28283491

The Shock and Vibration Digest, Volume 13, Number 1

DTIC Science & Technology

1981-01-01

Transfer matrices of different elements constituting expansion chamber mufflers have been used to develop a computer program for designing a... developed general computer programs using 10 ^=3 m^ Figure 4. Suppression of Flow-Acoustic Coupling by a Bridge Perforate [57] Figure 5. A Generally...the paper sessions are: • Environmental Stress Screening Theory • Screening Program Development /Implementa- tion • Screening Case Histories

Development Of An Educational Video To Improve Patient Knowledge And Communication With Their Healthcare Providers About Colorectal Cancer Screening

PubMed Central

Katz, Mira L.; Heaner, Sarah; Reiter, Paul; van Putten, Julie; Murray, Lee; McDougle, Leon; Cegala, Donald J.; Post, Douglas; David, Prabu; Slater, Michael; Paskett, Electra D.

2009-01-01

Background Low rates of colorectal cancer (CRC) screening persist due to individual, provider and system level barriers. Purpose To develop and obtain initial feedback about a CRC screening educational video from community members and medical professionals. Methods Focus groups of patients were conducted prior to the development of an educational video and focus groups of patients provided initial feedback about the developed CRC screening educational video. Medical personnel reviewed the video and made recommendations prior to final editing of the video. Results Patients identified CRC screening barriers and made suggestions about the information to include in the educational video. Their suggestions included using a healthcare provider to state the importance of completing CRC screening, demonstrate how to complete the fecal occult blood test, and that men and women from diverse ethnic groups and races could be included in the same video. Participants reviewed the developed video and mentioned that their suggestions were portrayed correctly, the video was culturally appropriate, and the information presented in the video was easy to understand. Medical personnel made suggestions on ways to improve the content and the delivery of the medical information prior to final editing of the video. Discussion Participants provided valuable information in the development of an educational video to improve patient knowledge and patient-provider communication about CRC screening. The educational video developed was based on the Protection Motivation Theory and addressed the colon cancer screening barriers identified in this mostly minority and low-income patient population. Future research will determine if CRC screening increases among patients who watch the educational video. Translation to Health Education Practice Educational videos can provide important information about CRC and CRC screening to average-risk adults. PMID:20209024

Smart-phone obesity prevention trial for adolescent boys in low-income communities: the ATLAS RCT.

PubMed

Smith, Jordan J; Morgan, Philip J; Plotnikoff, Ronald C; Dally, Kerry A; Salmon, Jo; Okely, Anthony D; Finn, Tara L; Lubans, David R

2014-09-01

The goal of this study was to evaluate the impact of the Active Teen Leaders Avoiding Screen-time (ATLAS) intervention for adolescent boys, an obesity prevention intervention using smartphone technology. ATLAS was a cluster randomized controlled trial conducted in 14 secondary schools in low-income communities in New South Wales, Australia. Participants were 361 adolescent boys (aged 12-14 years) considered at risk of obesity. The 20-week intervention was guided by self-determination theory and social cognitive theory and involved: teacher professional development, provision of fitness equipment to schools, face-to-face physical activity sessions, lunchtime student mentoring sessions, researcher-led seminars, a smartphone application and Web site, and parental strategies for reducing screen-time. Outcome measures included BMI and waist circumference, percent body fat, physical activity (accelerometers), screen-time, sugar-sweetened beverage intake, muscular fitness, and resistance training skill competency. Overall, there were no significant intervention effects for BMI, waist circumference, percent body fat, or physical activity. Significant intervention effects were found for screen-time (mean ± SE: -30 ± 10.08 min/d; P = .03), sugar-sweetened beverage consumption (mean: -0.6 ± 0.26 glass/d; P = .01), muscular fitness (mean: 0.9 ± 0.49 repetition; P = .04), and resistance training skills (mean: 5.7 ± 0.67 units; P < .001). This school-based intervention targeting low-income adolescent boys did not result in significant effects on body composition, perhaps due to an insufficient activity dose. However, the intervention was successful in improving muscular fitness, movement skills, and key weight-related behaviors. Copyright © 2014 by the American Academy of Pediatrics.

[Material base on Chinese medical theory of 'Fei and Dachang being interior-exteriorly correlated'].

PubMed

Li, Jie; Cheng, Xin; Jia, Yu-Hua

2011-02-01

By reviewing pertinent literatures, we found that there existed some defects in studying material base on Chinese medical theory of "Fei and Dachang being interior-exteriorly related", such as the low efficacy of research methods; the neglect of intestinal and respiratory microhabitat and Chinese medical functional condition; and the unconformity of research design with evidence-based medicinal requirements. Thereby, the authors offered that the researches method of initiating merely from sole material or line linkage path should be rejected. The new research strategy should be established based on the feature of the lung and large intestine network connective structure, cutting-in from correlative changes in the two terminals (respiratory system and intestinal tissue), and the intermedial key knot of connection (blood serum), screen out in high throughput the relevant materials adopting microecological, proteomic and metabonomic techniques, and catch hold of the knots of network as much as possible. Based on these to perfect the researches on coordinating mechanism of the network, and to establish a new strategy for future researching.

Chinese women's motivation to receive future screening: the role of social-demographic factors, knowledge and risk perception of cervical cancer.

PubMed

Gu, Can; Chan, Carmen W H; He, Guo-Ping; Choi, K C; Yang, Sheng-Bo

2013-04-01

This paper adopted Protection Motivation Theory (PMT) to examine Chinese women's knowledge and perceptions of cervical cancer risk and factors influencing their motivation to receive future screening. A cross-sectional survey was conducted with 167 Chinese women (142 women were willing to receive a screening in the future and 25 women were not) in 2007 to collect women's socio-demographic information and sexual history, perceptions related to body health and knowledge about cervical cancer and screening, and Protection Motivation Theory measures. The majority of women stated they intended to receive future screening and response efficacy was significantly associated with their intention. However, no significant association was observed between sexual history and protection motivation. Using multivariate analysis, cancer in relatives (odds ratio, OR = 9.97, 95% CI [1.44-436.3], p = 0.010), a perception that visiting a doctor regularly is important to health (OR = 9.85, 95% CI [1.61-999.9], p = 0.009)), and ever attending for cervical screening during the previous three years (OR = 3.49, 95% CI [1.23-11.02], p = 0.016) were significantly associated with women' motivation to receive future screening. The findings of this study highlight the important role of women's beliefs in the value of cervical screening and previous screening experience in motivating them to receive a screening. Education intervention is needed to provide information and raise public awareness about the importance of cervical screening to women's health. Culture-related beliefs and social motivational processes in addition to those specified by PMT need to be addressed. Copyright © 2012 Elsevier Ltd. All rights reserved.

Daughter-Initiated Cancer Screening Appeals to Mothers.

PubMed

Mosavel, M; Genderson, M W

2016-12-01

Youth-initiated health interventions may provide a much needed avenue for intergenerational dissemination of health information among families who bear the greatest burden from unequal distribution of morbidity and mortality. The findings presented in this paper are from a pilot study of the feasibility and impact of female youth-initiated messages (mostly daughters) encouraging adult female relatives (mostly mothers) to obtain cancer screening within low-income African American families living in a Southern US state. Results are compared between an intervention and control group. Intervention group youth (n = 22) were exposed to a 60-min interactive workshop where they were assisted to prepare a factual and emotional appeal to their adult relative to obtain specific screening. The face-to-face workshops were guided by the Elaboration Likelihood Model (ELM) and the Theory of Planned Behavior (TPB). Control group girls (n = 18) were only provided with a pamphlet with information about cancer screening and specific steps about how to encourage their relative to obtain screening. Intervention youth (86 %) and adults (82 %) reported that the message was shared while 71 % in the control group reported sharing or receiving the message. Importantly, more women in the intervention group reported that they obtained a screen (e.g., mammogram, Pap smear) directly based on the youth's appeal. These findings can have major implications for youth-initiated health promotion efforts, especially among hard-to-reach populations.

Daughter-Initiated Cancer Screening Appeals to Mothers

PubMed Central

Mosavel, Maghboeba; Genderson, Maureen Wilson

2015-01-01

Youth-initiated health interventions may provide a much needed avenue for intergenerational dissemination of health information among families who bear the greatest burden from unequal distribution of morbidity and mortality. The findings presented in this paper are from a pilot study of the feasibility and impact of female youth-initiated messages (mostly daughters) encouraging adult female relatives (mostly mothers) to obtain cancer screening within low income African American families living in a Southern US state. Results are compared between an intervention and control group. Intervention group youth (n=22) were exposed to a 60-minute interactive workshop where they were assisted to prepare a factual and emotional appeal to their adult relative to obtain specific screening. The face-to-face workshops were guided by the Elaboration Likelihood Model (ELM) and the Theory of Planned Behavior (TPB). Control group girls (n=18) were only provided with a pamphlet with information about cancer screening and specific steps about how to encourage their relative to obtain screening. Intervention youth (86%) and adults (82%) reported that the message was shared while 71% in the control group reported sharing or receiving the message. Importantly, more women in the intervention group reported that they obtained a screen (e.g., mammogram, Pap smear) directly based on the youth's appeal. These findings can have major implications for youth-initiated health promotion efforts, especially among hard-to-reach populations. PMID:26590969

Assessing the sustained impact of a school-based obesity prevention program for adolescent boys: the ATLAS cluster randomized controlled trial.

PubMed

Lubans, David R; Smith, Jordan J; Plotnikoff, Ronald C; Dally, Kerry A; Okely, Anthony D; Salmon, Jo; Morgan, Philip J

2016-08-20

Obesity prevention interventions targeting 'at-risk' adolescents are urgently needed. The aim of this study is to evaluate the sustained impact of the 'Active Teen Leaders Avoiding Screen-time' (ATLAS) obesity prevention program. Cluster RCT in 14 secondary schools in low-income communities of New South Wales, Australia. Participants were 361 adolescent boys (aged 12-14 years) 'at risk' of obesity. The intervention was based on Self-Determination Theory and Social Cognitive Theory and involved: professional development, fitness equipment for schools, teacher-delivered physical activity sessions, lunch-time activity sessions, researcher-led seminars, a smartphone application, and parental strategies. Assessments for the primary (body mass index [BMI], waist circumference) and secondary outcomes were conducted at baseline, 8- (post-intervention) and 18-months (follow-up). Analyses followed the intention-to-treat principle using linear mixed models. After 18-months, there were no intervention effects for BMI or waist circumference. Sustained effects were found for screen-time, resistance training skill competency, and motivational regulations for school sport. There were no clinically meaningful intervention effects for the adiposity outcomes. However, the intervention resulted in sustained effects for secondary outcomes. Interventions that more intensively target the home environment, as well as other socio-ecological determinants of obesity may be needed to prevent unhealthy weight gain in adolescents from low-income communities. Australian Clinical Trial Registry ACTRN12612000978864.

Finding Horndeski theories with Einstein gravity limits

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

McManus, Ryan; Lombriser, Lucas; Peñarrubia, Jorge, E-mail: ryanm@roe.ac.uk, E-mail: llo@roe.ac.uk, E-mail: jorpega@roe.ac.uk

The Horndeski action is the most general scalar-tensor theory with at most second-order derivatives in the equations of motion, thus evading Ostrogradsky instabilities and making it of interest when modifying gravity at large scales. To pass local tests of gravity, these modifications predominantly rely on nonlinear screening mechanisms that recover Einstein's Theory of General Relativity in regions of high density. We derive a set of conditions on the four free functions of the Horndeski action that examine whether a specific model embedded in the action possesses an Einstein gravity limit or not. For this purpose, we develop a new andmore » surprisingly simple scaling method that identifies dominant terms in the equations of motion by considering formal limits of the couplings that enter through the new terms in the modified action. This enables us to find regimes where nonlinear terms dominate and Einstein's field equations are recovered to leading order. Together with an efficient approximation of the scalar field profile, one can then further evaluate whether these limits can be attributed to a genuine screening effect. For illustration, we apply the analysis to both a cubic galileon and a chameleon model as well as to Brans-Dicke theory. Finally, we emphasise that the scaling method also provides a natural approach for performing post-Newtonian expansions in screened regimes.« less

Leadership Style, Decision Context, and the Poliheuristic Theory of Decision Making: An Experimental Analysis

ERIC Educational Resources Information Center

Keller, Jonathan W.; Yang, Yi Edward

2008-01-01

The poliheuristic (PH) theory of decision making has made important contributions to our understanding of political decision making but remains silent about certain key aspects of the decision process. Specifically, PH theory contends that leaders screen out politically unacceptable options, but it provides no guidance on (1) the crucial threshold…

How to Use the Pop-Screen in Literary Studies

ERIC Educational Resources Information Center

Reuber, Alexandra

2010-01-01

Teaching literary theory is fascinating for those who love the application of theory to a literary text, difficult for those who are of the opinion that theory destroys the actual beauty and value of the fictional source, and unfortunately often boring for those who are taught. This article, however, provides a popular approach to the introduction…

Does Human Capital Theory Explain the Value of Higher Education? A South African Case Study

ERIC Educational Resources Information Center

van der Merwe, Alex

2010-01-01

A perennial debate in the economics of education is whether human capital or screening/signalling theories best explain the value of schooling and hence the private demand for, in particular, higher education. Human capital theory proposes that formal training such as that offered by higher education institutions improves the productive capacity…

Theory of High-T{sub c} Superconducting Cuprates Based on Experimental Evidence

DOE R&D Accomplishments Database

Abrikosov, A. A.

1999-12-10

A model of superconductivity in layered high-temperature superconducting cuprates is proposed, based on the extended saddle point singularities in the electron spectrum, weak screening of the Coulomb interaction and phonon-mediated interaction between electrons plus a small short-range repulsion of Hund's, or spin-fluctuation, origin. This permits to explain the large values of T{sub c}, features of the isotope effect on oxygen and copper, the existence of two types of the order parameter, the peak in the inelastic neutron scattering, the positive curvature of the upper critical field, as function of temperature etc.

Simulation and analysis of chemical release in the ionosphere

NASA Astrophysics Data System (ADS)

Gao, Jing-Fan; Guo, Li-Xin; Xu, Zheng-Wen; Zhao, Hai-Sheng; Feng, Jie

2018-05-01

Ionospheric inhomogeneous plasma produced by single point chemical release has simple space-time structure, and cannot impact radio wave frequencies higher than Very High Frequency (VHF) band. In order to produce more complicated ionospheric plasma perturbation structure and trigger instabilities phenomena, multiple-point chemical release scheme is presented in this paper. The effects of chemical release on low latitude ionospheric plasma are estimated by linear instability growth rate theory that high growth rate represents high irregularities, ionospheric scintillation occurrence probability and high scintillation intension in scintillation duration. The amplitude scintillations and the phase scintillations of 150 MHz, 400 MHz, and 1000 MHz are calculated based on the theory of multiple phase screen (MPS), when they propagate through the disturbed area.

An entertainment-education colorectal cancer screening decision aid for African American patients: A randomized controlled trial.

PubMed

Hoffman, Aubri S; Lowenstein, Lisa M; Kamath, Geetanjali R; Housten, Ashley J; Leal, Viola B; Linder, Suzanne K; Jibaja-Weiss, Maria L; Raju, Gottumukkala S; Volk, Robert J

2017-04-15

Colorectal cancer screening rates for African American patients remain suboptimal. Patient decision aids designed with an entertainment-education approach have been shown to improve saliency and foster informed decision making. The purpose of this study was to assess whether an entertainment-education decision aid tailored for African American patients improved patients' decision making, attitudes, intentions, or colorectal cancer screening behavior. Eighty-nine participants were randomized to view 1) a patient decision aid video containing culturally tailored information about colorectal cancer screening options and theory-based support in decision making presented in an entertainment-education format or 2) an attention control video about hypertension that contained similarly detailed information. Participants met with their clinician and then completed follow-up questionnaires assessing their knowledge, decisional conflict, self-advocacy, attitudes, perceived social norms, and intentions. At 3 months, completion of screening was assessed by chart review. Viewing the culturally tailored decision aid significantly increased African American patients' knowledge of colorectal cancer screening recommendations and options. It also significantly reduced their decisional conflict and improved their self-advocacy. No significant differences were observed in participants' attitudes, norms, or intentions. At three months, 23% of all patients had completed a colonoscopy. Designing targeted, engaging patient decision aids for groups that receive suboptimal screening holds promise for improving patient decision making and self-advocacy. Additional research is warranted to investigate the effectiveness of such aids in clinical practices with suboptimal screening rates and on downstream behaviors (such as repeat testing). Cancer 2017;123:1401-1408. © 2016 American Cancer Society. © 2016 American Cancer Society.

Australian nurses in general practice, enabling the provision of cervical screening and well women’s health care services: a qualitative study

PubMed Central

2012-01-01

Background The role of Australian general practice nurses (PNs) has developed exponentially since the introduction of service based funding in 2005. In particular, their role has expanded to include cervical screening and well women’s health care services provided under the supervision of a general practitioner (GP). While previous research identifies barriers to the provision of these services, this study sought to investigate enablers for nurse led care in this area. Methods A number of grounded theory methods including constantly comparing data, concurrent data collection and analysis and theoretical sampling are utilised in this qualitative, exploratory study. A purposive sample of PNs who completed the required program of education in order to provide cervical screening and well women’s health care services was recruited to the study. Data is presented in categories, however a limitation of the study is that a fully integrated grounded theory was unable to be produced due to sampling constraints. Results Four enablers for the implementation of a change in the PN role to include cervical screening and well women’s health checks are identified in this study. These enablers are: GPs being willing to relinquish the role of cervical screener and well women’s health service provider; PNs being willing to expand their role to include cervical screening and well women’s health services; clients preferring a female practice nurse to meet their cervical screening and well women’s health needs; and the presence of a culture that fosters interprofessional teamwork. Seven strategies for successfully implementing change from the perspective of PNs are also constructed from the data. This study additionally highlights the lack of feedback on smear quality provided to PNs cervical screeners and well women’s health service providers. Conclusions The influence of consumers on the landscape of primary care service delivery in Australia is of particular note in this study. Developing interprofessional teams that maximise each health care provider’s role will be fundamental to comprehensive service delivery in the future. PMID:23145901

A new screening method for flunitrazepam in vodka and tequila by fluorescence spectroscopy.

PubMed

Leesakul, Nararak; Pongampai, Sirintip; Kanatharana, Proespichaya; Sudkeaw, Pravit; Tantirungrotechai, Yuthana; Buranachai, Chittanon

2013-01-01

A new screening method for flunitrazepam in colourless alcoholic beverages based on a spectroscopic technique is proposed. Absorption and steady-state fluorescence of flunitrazepam and its protonated form with various acids were investigated. The redshift of the wavelength of maximum absorption was distinctively observed in protonated flunitrazepam. An emissive fluorescence at 472 nm was detected in colourless spirits (vodka and tequila) at room temperature. 2-M perchloric acid was the most appropriated proton source. By using electron ionization mass spectrometry and time-dependent density functional theory calculations, the possible structure of protonated flunitrazepam was identified to be 2-nitro-N-methylacridone, an acridone derivative as opposed to 2-methylamino-5-nitro-2'-fluorobenzophenone, a benzophenone derivative. Copyright © 2012 John Wiley & Sons, Ltd.

Counting the ions surrounding nucleic acids

PubMed Central

2017-01-01

Abstract Nucleic acids are strongly negatively charged, and thus electrostatic interactions—screened by ions in solution—play an important role in governing their ability to fold and participate in biomolecular interactions. The negative charge creates a region, known as the ion atmosphere, in which cation and anion concentrations are perturbed from their bulk values. Ion counting experiments quantify the ion atmosphere by measuring the preferential ion interaction coefficient: the net total number of excess ions above, or below, the number expected due to the bulk concentration. The results of such studies provide important constraints on theories, which typically predict the full three-dimensional distribution of the screening cloud. This article reviews the state of nucleic acid ion counting measurements and critically analyzes their ability to test both analytical and simulation-based models. PMID:28034959

Expanded carrier screening: what determines intended participation and can this be influenced by message framing and narrative information?

PubMed

Voorwinden, Jan S; Buitenhuis, Anne H; Birnie, Erwin; Lucassen, Anneke M; Verkerk, Marian A; van Langen, Irene M; Plantinga, Mirjam; Ranchor, Adelita V

2017-06-01

Next-generation sequencing enabled us to create a population-based expanded carrier screening (ECS) test that simultaneously tests for 50 serious autosomal recessive diseases. Before offering this test universally, we wanted to know what factors are related to intended participation and how the general public can be informed about the test without being influenced in their intention to participate. We studied this by measuring to what extent 'message framing' and 'narrative information' can influence people's intended participation. Data were collected by means of an online survey of 504 potential users, and the factors examined were based on the Theory of Planned Behaviour and on previous research on intended participation in preconception carrier screening. Message framing was manipulated by explaining the risk of couple carriership in different ways, while narrative information was provided to only half of the respondents. The factors most positively related to intended participation were perceiving benefits of the screening, having a positive attitude towards the screening, having no religion, having an actual child wish and experiencing the choice to participate as easy. Perceived benefits and a positive attitude were most influential factors by far. Message framing and narrative information had no significant effect on intended participation, reinforcing that message framing and narrative information can help to inform the general public about ECS without influencing their intended participation. Future research should study if the importance of perceived benefits and a positive attitude can be replicated when other factors are included and when actual participation is measured instead of intended participation.

Role of Psychosocial Factors and Health Literacy in Pregnant Women's Intention to Use a Decision Aid for Down Syndrome Screening: A Theory-Based Web Survey.

PubMed

Delanoë, Agathe; Lépine, Johanie; Turcotte, Stéphane; Leiva Portocarrero, Maria Esther; Robitaille, Hubert; Giguère, Anik Mc; Wilson, Brenda J; Witteman, Holly O; Lévesque, Isabelle; Guillaumie, Laurence; Légaré, France

2016-10-28

Deciding about undergoing prenatal screening is difficult, as it entails risks, potential loss and regrets, and challenges to personal values. Shared decision making and decision aids (DAs) can help pregnant women give informed and values-based consent or refusal to prenatal screening, but little is known about factors influencing the use of DAs. The objective of this study was to identify the influence of psychosocial factors on pregnant women's intention to use a DA for prenatal screening for Down syndrome (DS). We also added health literacy variables to explore their influence on pregnant women's intention. We conducted a survey of pregnant women in the province of Quebec (Canada) using a Web panel. Eligibility criteria included age >18 years, >16 weeks pregnant, low-risk pregnancy, and having decided about prenatal screening for the current pregnancy. We collected data based on an extended version of the Theory of Planned Behavior assessing 7 psychosocial constructs (intention, attitude, anticipated regret, subjective norm, descriptive norm, moral norm, and perceived control), 3 related sets of beliefs (behavioral, normative, and control beliefs), 4 health literacy variables, and sociodemographics. Eligible women watched a video depicting the behavior of interest before completing a Web-based questionnaire. We performed descriptive, bivariate, and ordinal logistic regression analyses. Of the 383 eligible pregnant women who agreed to participate, 350 pregnant women completed the Web-based questionnaire and 346 were retained for analysis (completion rate 350/383, 91.4%; mean age 30.1, SD 4.3, years). In order of importance, factors influencing intention to use a DA for prenatal screening for DS were attitude (odds ratio, OR, 9.16, 95% CI 4.02-20.85), moral norm (OR 7.97, 95% CI 4.49-14.14), descriptive norm (OR 2.83, 95% CI 1.63-4.92), and anticipated regret (OR 2.43, 95% CI 1.71-3.46). Specific attitudinal beliefs significantly related to intention were that using a DA would reassure them (OR 2.55, 95% CI 1.73-4.01), facilitate their reflections with their spouse (OR 1.55, 95% CI 1.05-2.29), and let them know about the advantages of doing or not doing the test (OR 1.53, 95% CI 1.05-2.24). Health literacy did not add to the predictive power of our model (P values range .43-.92). Implementation interventions targeting the use of a DA for prenatal screening for DS by pregnant women should address a number of modifiable factors, especially by introducing the advantages of using the DA (attitude), informing pregnant women that they might regret not using it (anticipated regret), and presenting the use of DAs as a common practice (descriptive norm). However, interventions on moral norms related to the use of DA should be treated with caution. Further studies that include populations with low health literacy are needed before decisive claims can be made. ©Agathe Delanoë, Johanie Lépine, Stéphane Turcotte, Maria Esther Leiva Portocarrero, Hubert Robitaille, Anik MC Giguère, Brenda J Wilson, Holly O Witteman, Isabelle Lévesque, Laurence Guillaumie, France Légaré. Originally published in the Journal of Medical Internet Research (http://www.jmir.org), 28.10.2016.

Horndeski extension of the minimal theory of quasidilaton massive gravity

NASA Astrophysics Data System (ADS)

De Felice, Antonio; Mukohyama, Shinji; Oliosi, Michele

2017-11-01

The minimal theory of quasidilaton massive gravity allows for a stable self-accelerating de Sitter solution in a wide range of parameters. On the other hand, in order for the theory to be compatible with local gravity tests, the fifth force due to the quasidilaton scalar needs to be screened at local scales. The present paper thus extends the theory by inclusion of a cubic Horndeski term in a way that (i) respects the quasidilaton global symmetry, that (ii) maintains the physical degrees of freedom in the theory being 3, that (iii) can accommodate the Vainshtein screening mechanism, and that (iv) still allows for a stable self-accelerating de Sitter solution. After adding the Horndeski term (and a k -essence type nonlinear kinetic term as well) to the precursor action, we switch to the Hamiltonian language and find a complete set of independent constraints. We then construct the minimal theory with 3 physical degrees of freedom by carefully adding a pair of constraints to the total Hamiltonian of the precursor theory. Switching back to the Lagrangian language, we study cosmological solutions and their stability in the minimal theory. In particular, we show that a self-accelerating de Sitter solution is stable for a wide range of parameters. Furthermore, as in the minimal theory of massive gravity, the propagation speed of the massive gravitational waves in the high momentum limit precisely agrees with the speed of light.

Structure and osmotic pressure of ionic microgel dispersions

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

Hedrick, Mary M.; Department of Chemistry and Biochemistry, North Dakota State University, Fargo, North Dakota 58108-6050; Chung, Jun Kyung

We investigate structural and thermodynamic properties of aqueous dispersions of ionic microgels—soft colloidal gel particles that exhibit unusual phase behavior. Starting from a coarse-grained model of microgel macroions as charged spheres that are permeable to microions, we perform simulations and theoretical calculations using two complementary implementations of Poisson-Boltzmann (PB) theory. Within a one-component model, based on a linear-screening approximation for effective electrostatic pair interactions, we perform molecular dynamics simulations to compute macroion-macroion radial distribution functions, static structure factors, and macroion contributions to the osmotic pressure. For the same model, using a variational approximation for the free energy, we compute bothmore » macroion and microion contributions to the osmotic pressure. Within a spherical cell model, which neglects macroion correlations, we solve the nonlinear PB equation to compute microion distributions and osmotic pressures. By comparing the one-component and cell model implementations of PB theory, we demonstrate that the linear-screening approximation is valid for moderately charged microgels. By further comparing cell model predictions with simulation data for osmotic pressure, we chart the cell model’s limits in predicting osmotic pressures of salty dispersions.« less

ASTROPHYSICS. Atom-interferometry constraints on dark energy.

PubMed

Hamilton, P; Jaffe, M; Haslinger, P; Simmons, Q; Müller, H; Khoury, J

2015-08-21

If dark energy, which drives the accelerated expansion of the universe, consists of a light scalar field, it might be detectable as a "fifth force" between normal-matter objects, in potential conflict with precision tests of gravity. Chameleon fields and other theories with screening mechanisms, however, can evade these tests by suppressing the forces in regions of high density, such as the laboratory. Using a cesium matter-wave interferometer near a spherical mass in an ultrahigh-vacuum chamber, we reduced the screening mechanism by probing the field with individual atoms rather than with bulk matter. We thereby constrained a wide class of dark energy theories, including a range of chameleon and other theories that reproduce the observed cosmic acceleration. Copyright © 2015, American Association for the Advancement of Science.

Atomic-scale compensation phenomena at polar interfaces.

PubMed

Chisholm, Matthew F; Luo, Weidong; Oxley, Mark P; Pantelides, Sokrates T; Lee, Ho Nyung

2010-11-05

The interfacial screening charge that arises to compensate electric fields of dielectric or ferroelectric thin films is now recognized as the most important factor in determining the capacitance or polarization of ultrathin ferroelectrics. Here we investigate using aberration-corrected electron microscopy and density-functional theory to show how interfaces cope with the need to terminate ferroelectric polarization. In one case, we show evidence for ionic screening, which has been predicted by theory but never observed. For a ferroelectric film on an insulating substrate, we found that compensation can be mediated by an interfacial charge generated, for example, by oxygen vacancies.

On the Numerical Analysis of Decay Rate Enhancement in Metallic Environment

NASA Astrophysics Data System (ADS)

Mehedinteanu, S.

2007-10-01

Motivated on the very recent experiments to determine the acceleration of the alpha decay of meta-stable radionuclides in metallic environment some work has been done to strengthten the importance in the process of electrons screening in metals. Thus, by combining the Gamow decay theory with electrostatic screening in Debye-Hückel approximation (jellium model) a formula for ``the shift'' in screening energy which enters in the decay enhancement factor expression that copes well with these experiments has been derived. It was established that to simulate the poly-atoms system containing decaying isotopes in QM&MD codes calculations, and to include ``the screening energy shift'' of protons, decay alpha, beta+ particles due to all surrounding interacting effects, it is sufficiently only to substitute the code ruly pseudo-potential input for hydrogen-like atoms (including alpha) by a screened Coulomb potential as from the well-known Gamow alpha decay theory. For demonstration is used the QM&MD code package which usually performs density-functional theory (DFT) total-energy calculations for materials ranging from insulators to transition metals. This package employs first-principles pseudo-potentials and a plane-wave basis-set, and it was used to do a special calculus for some metal environments (Pd) where protons-deuterons are implanted or when it is alloyed with a radionuclide-like isotopes (174Hf72), the results compare well with the existing experiments on the decay enhancement. These works give further arguments for a cheap solution to remove the transuranic waste (involving all alpha-decay) of used-up rods of fission reactors in a time period of a few years.

A psychosocial analysis of parents' decisions for limiting their young child's screen time: An examination of attitudes, social norms and roles, and control perceptions.

PubMed

Hamilton, Kyra; Spinks, Teagan; White, Katherine M; Kavanagh, David J; Walsh, Anne M

2016-05-01

Preschool-aged children spend substantial amounts of time engaged in screen-based activities. As parents have considerable control over their child's health behaviours during the younger years, it is important to understand those influences that guide parents' decisions about their child's screen time behaviours. A prospective design with two waves of data collection, 1 week apart, was adopted. Parents (n = 207) completed a Theory of Planned Behaviour (TPB)-based questionnaire, with the addition of parental role construction (i.e., parents' expectations and beliefs of responsibility for their child's behaviour) and past behaviour. A number of underlying beliefs identified in a prior pilot study were also assessed. The model explained 77% (with past behaviour accounting for 5%) of the variance in intention and 50% (with past behaviour accounting for 3%) of the variance in parental decisions to limit child screen time. Attitude, subjective norms, perceived behavioural control, parental role construction, and past behaviour predicted intentions, and intentions and past behaviour predicted follow-up behaviour. Underlying screen time beliefs (e.g., increased parental distress, pressure from friends, inconvenience) were also identified as guiding parents' decisions. Results support the TPB and highlight the importance of beliefs for understanding parental decisions for children's screen time behaviours, as well as the addition of parental role construction. This formative research provides necessary depth of understanding of sedentary lifestyle behaviours in young children which can be adopted in future interventions to test the efficacy of the TPB mechanisms in changing parental behaviour for their child's health. What is already known on this subject? Identifying determinants of child screen time behaviour is vital to the health of young people. Social-cognitive and parental role constructions are key influences of parental decision-making. Little is known about the processes guiding parents' decisions to limit their child's screen time. What does this study add? Parental role construction and TPB social-cognitive factors influence parental decisions. The beliefs of parents for their child's behaviour were identified. A range of beliefs guide parents' decisions for their child's screen time viewing. © 2015 The British Psychological Society.

Adaptation of an evidence-based intervention to promote colorectal cancer screening: a quasi-experimental study

PubMed Central

2014-01-01

Background To accelerate the translation of research findings into practice for underserved populations, we investigated the adaptation of an evidence-based intervention (EBI), designed to increase colorectal cancer (CRC) screening in one limited English-proficient (LEP) population (Chinese), for another LEP group (Vietnamese) with overlapping cultural and health beliefs. Methods Guided by Diffusion of Innovations Theory, we adapted the EBI to achieve greater reach. Core elements of the adapted intervention included: small media (a DVD and pamphlet) translated into Vietnamese from Chinese; medical assistants distributing the small media instead of a health educator; and presentations on CRC screening to the medical assistants. A quasi-experimental study examined CRC screening adherence among eligible Vietnamese patients at the intervention and control clinics, before and after the 24-month intervention. The proportion of the adherence was assessed using generalized linear mixed models that account for clustering under primary care providers and also within-patient correlation between baseline and follow up. Results Our study included two cross-sectional samples: 1,016 at baseline (604 in the intervention clinic and 412 in the control clinic) and 1,260 post-intervention (746 in the intervention and 514 in the control clinic), including appreciable overlaps between the two time points. Pre-post change in CRC screening over time, expressed as an odds ratio (OR) of CRC screening adherence by time, showed a marginally-significant greater increase in CRC screening adherence at the intervention clinic compared to the control clinic (the ratio of the two ORs = 1.42; 95% CI 0.95, 2.15). In the sample of patients who were non-adherent to CRC screening at baseline, compared to the control clinic, the intervention clinic had marginally-significant greater increase in FOBT (adjusted OR = 1.77; 95% CI 0.98, 3.18) and a statistically-significantly greater increase in CRC screening adherence (adjusted OR = 1.70; 95% CI 1.05, 2.75). Conclusions Theoretically guided adaptations of EBIs may accelerate the translation of research into practice. Adaptation has the potential to mitigate health disparities for hard-to-reach populations in a timely manner. PMID:24989083

Population Screening for Colorectal Cancer Means Getting FIT: The Past, Present, and Future of Colorectal Cancer Screening Using the Fecal Immunochemical Test for Hemoglobin (FIT)

PubMed Central

Fraser, Callum G.; Halloran, Stephen P.; Young, Graeme P.

2014-01-01

Fecal immunochemical tests for hemoglobin (FIT) are changing the manner in which colorectal cancer (CRC) is screened. Although these tests are being performed worldwide, why is this test different from its predecessors? What evidence supports its adoption? How can this evidence best be used? This review addresses these questions and provides an understanding of FIT theory and practices to expedite international efforts to implement the use of FIT in CRC screening. PMID:24672652

Electrostatic Technology for Control of Dust and Hydrocarbon Vapors in High Power Laser Systems.

DTIC Science & Technology

1982-04-01

interest in that there is an intense corona discharge from the high volt- age (-17 kV) needles to the grounded screen as shown in Figure 1. This generates a...optimum arrangement, in terms of needle -to- needle spacing, needle -to-screen distance and screen opening dimensions? b. How shall the repulsion system be...the optical path? 5 To settle question a, it was necessary to build and test a number of needle -screen systems since there was no theory that could be

Aircraft noise propagation. [sound diffraction by wings

NASA Technical Reports Server (NTRS)

Hadden, W. J.; Pierce, A. D.

1978-01-01

Sound diffraction experiments conducted at NASA Langley Research Center to study the acoustical implications of the engine over wing configuration (noise-shielding by wing) and to provide a data base for assessing various theoretical approaches to the problem of aircraft noise reduction are described. Topics explored include the theory of sound diffraction around screens and wedges; the scattering of spherical waves by rectangular patches; plane wave diffraction by a wedge with finite impedence; and the effects of ambient flow and distribution sources.

Restoring Fun to Game Theory

ERIC Educational Resources Information Center

Dixit, Avinash

2005-01-01

The author suggests methods for teaching game theory at an introductory level, using interactive games to be played in the classroom or in computer clusters, clips from movies to be screened and discussed, and excerpts from novels and historical books to be read and discussed.

The Design of a Multi-component Intervention to Promote Screening Mammography in an American Indian Community: The Native Women's Health Project

PubMed Central

Tolma, Eleni L.; Engelman, Kimberly; Stoner, Julie A.; Thomas, Cara; Joseph, Stephanie; Li, Ji; Blackwater, Cecily; Henderson, J. Neil; Carson, L. D.; Neely, Norma; Edwards, Tewanna

2016-01-01

Background Breast cancer is an important public health issue among American Indian/Alaska Native (AI/AN) women in the US. This article describes the design and implementation of a culturally sensitive intervention to promote breast health among AI/AN women through a hybrid model that incorporates clinical and community-based approaches. This is one of the first studies using this model addressing breast cancer disparities among AI/AN populations in the US. Methods The Theory of Planned Behavior was used as the guiding framework of the intervention and Community Based Participatory Research was the primary vehicle for the intervention planning and implementation. Three preliminary studies took place that aimed to identify qualitatively and quantitatively what deterred or encouraged AI women to get past or future mammograms. The research results were shared with community members who, through a prioritization process, identified the theoretical focus of the intervention and its corresponding activities. The priority population consisted of AI women ages 40–74, with no recent mammogram, and no breast cancer history. Results The intervention centered on the promotion of social modeling and physician recommendation. The main corresponding activities included enhancing patient-physician communication about screening mammography through a structured dialogue, receipt of a breast cancer brochure, participation in an inter-generational discussion group, and a congratulatory bracelet upon receipt of a mammogram. Environmental and policy related changes also were developed. Conclusion Creating a theory-based, culturally-sensitive intervention through tribal participatory research is a challenging approach towards eliminating breast cancer disparities among hard-to-reach populations. PMID:29546205

[Analysis on traditional Chinese medicine prescriptions treating cancer-related anorexia syndrome based on grey system theory combined with multivariate analysis method and discovery of new prescriptions].

PubMed

Chen, Song-Lin; Chen, Cong; Zhu, Hui; Li, Jing; Pang, Yan

2016-01-01

Cancer-related anorexia syndrome (CACS) is one of the main causes for death at present as well as a syndrome seriously harming patients' quality of life, treatment effect and survival time. In current clinical researches, there are fewer reports about empirical traditional Chinese medicine(TCM) prescriptions and patent prescriptions treating CACS, and prescription rules are rarely analyzed in a systematic manner. As the hidden rules are not excavated, it is hard to have an innovative discovery and knowledge of clinical medication. In this paper, the grey screening method combined with the multivariate statistical method was used to build the ″CACS prescriptions database″. Based on the database, totally 359 prescriptions were selected, the frequency of herbs in prescription was determined, and commonly combined drugs were evolved into 4 new prescriptions for different syndromes. Prescriptions of TCM in treatment of CACS gave priority to benefiting qi for strengthening spleen, also laid emphasis on replenishing kidney essence, dispersing stagnated liver-qi and dispersing lung-qi. Moreover, interdependence and mutual promotion of yin and yang should be taken into account to reflect TCM's holism and theory for treatment based on syndrome differentiation. The grey screening method, as a valuable traditional Chinese medicine research-supporting method, can be used to subjectively and objectively analyze prescription rules; and the new prescriptions can provide reference for the clinical use of TCM for treating CACS and the drug development. Copyright© by the Chinese Pharmaceutical Association.

Riding on irrelevant operators

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

De Rham, Claudia; Ribeiro, Raquel H., E-mail: Claudia.deRham@case.edu, E-mail: RaquelHRibeiro@case.edu

2014-11-01

We investigate the stability of a class of derivative theories known as P(X) and Galileons against corrections generated by quantum effects. We use an exact renormalisation group approach to argue that these theories are stable under quantum corrections at all loops in regions where the kinetic term is large compared to the strong coupling scale. This is the regime of interest for screening or Vainshtein mechanisms, and in inflationary models that rely on large kinetic terms. Next, we clarify the role played by the symmetries. While symmetries protect the form of the quantum corrections, theories equipped with more symmetries domore » not necessarily have a broader range of scales for which they are valid. We show this by deriving explicitly the regime of validity of the classical solutions for P(X) theories including Dirac-Born-Infeld (DBI) models, both in generic and for specific background field configurations. Indeed, we find that despite the existence of an additional symmetry, the DBI effective field theory has a regime of validity similar to an arbitrary P(X) theory. We explore the implications of our results for both early and late universe contexts. Conversely, when applied to static and spherical screening mechanisms, we deduce that the regime of validity of typical power-law P(X) theories is much larger than that of DBI.« less

First-principles data-driven discovery of transition metal oxides for artificial photosynthesis

NASA Astrophysics Data System (ADS)

Yan, Qimin

We develop a first-principles data-driven approach for rapid identification of transition metal oxide (TMO) light absorbers and photocatalysts for artificial photosynthesis using the Materials Project. Initially focusing on Cr, V, and Mn-based ternary TMOs in the database, we design a broadly-applicable multiple-layer screening workflow automating density functional theory (DFT) and hybrid functional calculations of bulk and surface electronic and magnetic structures. We further assess the electrochemical stability of TMOs in aqueous environments from computed Pourbaix diagrams. Several promising earth-abundant low band-gap TMO compounds with desirable band edge energies and electrochemical stability are identified by our computational efforts and then synergistically evaluated using high-throughput synthesis and photoelectrochemical screening techniques by our experimental collaborators at Caltech. Our joint theory-experiment effort has successfully identified new earth-abundant copper and manganese vanadate complex oxides that meet highly demanding requirements for photoanodes, substantially expanding the known space of such materials. By integrating theory and experiment, we validate our approach and develop important new insights into structure-property relationships for TMOs for oxygen evolution photocatalysts, paving the way for use of first-principles data-driven techniques in future applications. This work is supported by the Materials Project Predictive Modeling Center and the Joint Center for Artificial Photosynthesis through the U.S. Department of Energy, Office of Basic Energy Sciences, Materials Sciences and Engineering Division, under Contract No. DE-AC02-05CH11231. Computational resources also provided by the Department of Energy through the National Energy Supercomputing Center.

Application of health behavior theories to breast cancer screening among Asian women.

PubMed

Ahmadian, Maryam; Samah, Asnarulkhadi Abu

2013-01-01

Although breast cancer is a major public health worry among Asian women, adherence to screening for the disease remains an obstacle to its prevention. A variety of psycho-social and cultural factors predispose women to delay or avoidance of screening for breast cancer symptoms at the early stages when cure is most likely to be successful. Yet few interventions implemented to date to address this condition in this region have drawn on health behavior theory. This paper reviews the existing literature on several cognitive theories and models associated with breast cancer screening, with an emphasis on the work that has been done in relation to Asian women. To conduct this review, a number of electronic databases were searched with context-appropriate inclusion criteria. Little empirical work was found that specifically addressed the applicability of health theories in promoting adherence to the current breast cancer prevention programs Among Asian women. However, a few studies were found that addressed individual cognitive factors that are likely to encourage women's motivation to protect themselves against breast cancer in this region of the world. The findings suggest that multi-level, socio-cultural interventions that focus on cognitive factors have much promise with this issue. Interventions are needed that effectively and efficiently target the personal motivation of at-risk Asian women to seek out and engage in breast cancer prevention. Concerning implications, personal motivation to seek out and engage in individual preventive actions for breast cancer prevention among Asian women is a timely, high priority target with practical implications for community development and health promotion. Further studies using qualitative, anthropologic approaches shaped for implementation in multi-ethnic Asian settings are needed to inform and guide these interventions.

Kinetic Theory of Plasmas

DTIC Science & Technology

2009-09-01

RTO-EN-AVT-162 means of a Coulomb potential screened at the Debye length (Delcroix and Bers, 1984; Balescu , 1988). 4. The plasma is composed of...Theory of Plasmas 2 - 28 RTO-EN-AVT-162 References Balescu , R. (1988). Transport Processes in Plasmas. Elsevier, Amsterdam. Barth, T. (2008

A Prelongitudinal Test of Motor Stage Theory.

ERIC Educational Resources Information Center

Langendorfer, Stephen

1987-01-01

A test of motor stage theory was conducted to screen cross-sectionally for the existence of "horizontal structure" among motor sequences within four movement components of overarm throwing and overarm striking for force. Subjects were 58 preschool and elementary school boys. Findings are discussed. (Author/MT)

Physics in Screening Environments

NASA Astrophysics Data System (ADS)

Certik, Ondrej

In the current study, we investigated atoms in screening environments like plasmas. It is common practice to extract physical data, such as temperature and electron densities, from plasma experiments. We present results that address inherent computational difficulties that arise when the screening approach is extended to include the interaction between the atomic electrons. We show that there may arise an ambiguity in the interpretation of physical properties, such as temperature and charge density, from experimental data due to the opposing effects of electron-nucleus screening and electron-electron screening. The focus of the work, however, is on the resolution of inherent computational challenges that appear in the computation of two-particle matrix elements. Those enter already at the Hartree-Fock level. Furthermore, as examples of post Hartree-Fock calculations, we show second-order Green's function results and many body perturbation theory results of second order. A self-contained derivation of all necessary equations has been included. The accuracy of the implementation of the method is established by comparing standard unscreened results for various atoms and molecules against literature for Hartree-Fock as well as Green's function and many body perturbation theory. The main results of the thesis are presented in the chapter called Screened Results, where the behavior of several atomic systems depending on electron-electron and electron-nucleus Debye screening was studied. The computer code that we have developed has been made available for anybody to use. Finally, we present and discuss results obtained for screened interactions. We also examine thoroughly the computational details of the calculations and particular implementations of the method.

Methods for designing interventions to change healthcare professionals' behaviour: a systematic review.

PubMed

Colquhoun, Heather L; Squires, Janet E; Kolehmainen, Niina; Fraser, Cynthia; Grimshaw, Jeremy M

2017-03-04

Systematic reviews consistently indicate that interventions to change healthcare professional (HCP) behaviour are haphazardly designed and poorly specified. Clarity about methods for designing and specifying interventions is needed. The objective of this review was to identify published methods for designing interventions to change HCP behaviour. A search of MEDLINE, Embase, and PsycINFO was conducted from 1996 to April 2015. Using inclusion/exclusion criteria, a broad screen of abstracts by one rater was followed by a strict screen of full text for all potentially relevant papers by three raters. An inductive approach was first applied to the included studies to identify commonalities and differences between the descriptions of methods across the papers. Based on this process and knowledge of related literatures, we developed a data extraction framework that included, e.g. level of change (e.g. individual versus organization); context of development; a brief description of the method; tasks included in the method (e.g. barrier identification, component selection, use of theory). 3966 titles and abstracts and 64 full-text papers were screened to yield 15 papers included in the review, each outlining one design method. All of the papers reported methods developed within a specific context. Thirteen papers included barrier identification and 13 included linking barriers to intervention components; although not the same 13 papers. Thirteen papers targeted individual HCPs with only one paper targeting change across individual, organization, and system levels. The use of theory and user engagement were included in 13/15 and 13/15 papers, respectively. There is an agreement across methods of four tasks that need to be completed when designing individual-level interventions: identifying barriers, selecting intervention components, using theory, and engaging end-users. Methods also consist of further additional tasks. Examples of methods for designing the organisation and system-level interventions were limited. Further analysis of design tasks could facilitate the development of detailed guidelines for designing interventions.

Cervical cancer screening among university students in South Africa: a theory based study.

PubMed

Hoque, Muhammad Ehsanu; Ghuman, Shanaz; Coopoosmay, Roger; Van Hal, Guido

2014-01-01

Cervical cancer is a serious public health problem in South Africa. Even though the screening is free in health facilities in South Africa, the Pap smear uptake is very low. The objective of the study is to investigate the knowledge and beliefs of female university students in South Africa. A cross sectional study was conducted among university women in South Africa to elicit information about knowledge and beliefs, and screening history. A total of 440 students completed the questionnaire. The average age of the participants was 20.39 years (SD  = 1.71 years). Regarding cervical cancer, 55.2% (n = 243) had ever heard about it. Results indicated that only 15% (22/147) of the students who had ever had sex and had heard about cervical cancer had taken a Pap test. Pearson correlation analysis showed that cervical cancer knowledge had a significantly negative relationship with barriers to cervical cancer screening. Susceptibility and seriousness score were significantly moderately correlated with benefit and motivation score as well as barrier score. Self-efficacy score also had a moderate correlation with benefit and motivation score. Students who had had a Pap test showed a significantly lower score in barriers to being screened compared to students who had not had a Pap test. This study showed that educated women in South Africa lack complete information on cervical cancer. Students who had had a Pap test had significantly lower barriers to cervical cancer screening than those students who had not had a Pap test.

Barriers of and facilitators to physician recommendation of colorectal cancer screening.

PubMed

Guerra, Carmen E; Schwartz, J Sanford; Armstrong, Katrina; Brown, Jamin S; Halbert, Chanita Hughes; Shea, Judy A

2007-12-01

Colorectal cancer screening (CRCS) has been demonstrated to be effective and is consistently recommended by clinical practice guidelines. However, only slightly over half of all Americans have ever been screened. Patients cite physician recommendation as the most important motivator of screening. This study explored the barriers of and facilitators to physician recommendation of CRCS. A 3-component qualitative study to explore the barriers of and facilitators to physician recommendation of CRCS: in-depth, semistructured interviews with 29 purposively sampled, community- and academic-based primary care physicians; chart-stimulated recall, a technique that utilizes patient charts to probe physician recall and provide context about the barriers of and facilitators to physician recommendation of CRCS during actual clinic encounters; and focus groups with 18 academic primary care physicians. Grounded theory techniques of analysis were used. All the participating physicians were aware of and recommended CRCS. The overwhelmingly preferred test was colonoscopy. Barriers of physician recommendation of CRCS included patient comorbidities, prior patient refusal of screening, physician forgetfulness, acute care visits, lack of time, and lack of reminder systems and test tracking systems. Facilitators to physician recommendation of CRCS included patient request, patient age 50-59, physician positive attitudes about CRCS, physician prioritization of screening, visits devoted to preventive health, reminders, and incentives. There are multiple physician, patient, and system barriers to recommending CRCS. Thus, interventions may need to target barriers at multiple levels to successfully increase physician recommendation of CRCS.

Along the way to developing a theory of the program: a re-examination of the conceptual framework as an organizing strategy.

PubMed

Helitzer, Deborah L; Sussman, Andrew L; Hoffman, Richard M; Getrich, Christina M; Warner, Teddy D; Rhyne, Robert L

2014-08-01

Conceptual frameworks (CF) have historically been used to develop program theory. We re-examine the literature about the role of CF in this context, specifically how they can be used to create descriptive and prescriptive theories, as building blocks for a program theory. Using a case example of colorectal cancer screening intervention development, we describe the process of developing our initial CF, the methods used to explore the constructs in the framework and revise the framework for intervention development. We present seven steps that guided the development of our CF: (1) assemble the "right" research team, (2) incorporate existing literature into the emerging CF, (3) construct the conceptual framework, (4) diagram the framework, (5) operationalize the framework: develop the research design and measures, (6) conduct the research, and (7) revise the framework. A revised conceptual framework depicted more complicated inter-relationships of the different predisposing, enabling, reinforcing, and system-based factors. The updated framework led us to generate program theory and serves as the basis for designing future intervention studies and outcome evaluations. A CF can build a foundation for program theory. We provide a set of concrete steps and lessons learned to assist practitioners in developing a CF. Copyright © 2014 Elsevier Ltd. All rights reserved.

University Preparation for Native American Students: Theory and Application.

ERIC Educational Resources Information Center

Beaty, Jeanna; Chiste, Katherine Beaty

1986-01-01

Describes a summer program at the University of Lethbridge designed to improve the retention and graduation rates of Native American students, most of whom are adult reentry students with incomplete secondary school preparation; covers program theory, cultural background, staffing, student screening, curriculum, and outcomes. (JHZ)

Extrasolar planets as a probe of modified gravity

NASA Astrophysics Data System (ADS)

Vargas dos Santos, Marcelo; Mota, David F.

2017-06-01

We propose a new method to test modified gravity theories, taking advantage of the available data on extrasolar planets. We computed the deviations from the Kepler third law and use that to constrain gravity theories beyond General Relativity. We investigate gravity models which incorporate three screening mechanisms: the Chameleon, the Symmetron and the Vainshtein. We find that data from exoplanets orbits are very sensitive to the screening mechanisms putting strong constraints in the parameter space for the Chameleon models and the Symmetron, complementary and competitive to other methods, like interferometers and solar system. With the constraints on Vainshtein we are able to work beyond the hypothesis that the crossover scale is of the same order of magnitude than the Hubble radius rc ∼ H0-1, which makes the screening work automatically, testing how strong this hypothesis is and the viability of other scales.

Item response theory analysis of the Lichtenberg Financial Decision Screening Scale.

PubMed

Teresi, Jeanne A; Ocepek-Welikson, Katja; Lichtenberg, Peter A

2017-01-01

The focus of these analyses was to examine the psychometric properties of the Lichtenberg Financial Decision Screening Scale (LFDSS). The purpose of the screen was to evaluate the decisional abilities and vulnerability to exploitation of older adults. Adults aged 60 and over were interviewed by social, legal, financial, or health services professionals who underwent in-person training on the administration and scoring of the scale. Professionals provided a rating of the decision-making abilities of the older adult. The analytic sample included 213 individuals with an average age of 76.9 (SD = 10.1). The majority (57%) were female. Data were analyzed using item response theory (IRT) methodology. The results supported the unidimensionality of the item set. Several IRT models were tested. Ten ordinal and binary items evidenced a slightly higher reliability estimate (0.85) than other versions and better coverage in terms of the range of reliable measurement across the continuum of financial incapacity.

Culturally Competent Training Program: A Key to Training Lay Health Advisors for Promoting Breast Cancer Screening

ERIC Educational Resources Information Center

Yu, Mei-yu; Song, Lixin; Seetoo, Amy; Cai, Cuijuan; Smith, Gary; Oakley, Deborah

2007-01-01

The lay health advisor (LHA) training program for breast cancer screening was conducted among Chinese-English bilingual trainees residing in Southeast Michigan. Guided by Bandura's Social Learning Theory, the development of the training curriculum followed the health communication process recommended by the National Cancer Institute. Data analysis…

Extending the Global Dialogue about Media, Technology, Screen Time, and Young Children

ERIC Educational Resources Information Center

Ernest, James M.; Causey, Cora; Newton, Allison B.; Sharkins, Kimberly; Summerlin, Jennifer; Albaiz, Najla

2014-01-01

Questions about the potential benefits and dangers of media and technology use abound, with competing theories regarding its effects among young children. This article explores global perspectives on children's exposure to media, technology, and screen time (MeTS) in the schools, homes, and communities of an increasingly technology-driven world.…

Are All Latinas the Same?: Perceived Breast Cancer Screening Barriers and Facilitative Conditions

ERIC Educational Resources Information Center

Buki, Lydia P.; Borrayo, Evelinn A.; Feigal, Benjamin M.; Carrillo, Iris Y.

2004-01-01

In this article, we examine perceived breast cancer screening barriers and facilitative conditions for immigrant women from Mexico, Puerto Rico, Cuba, El Salvador, and South America (N=58). Focus groups conducted separately with women of each ancestry were analyzed using grounded theory methods. Identified barriers comprise secrecy, lack of…

Re-Mediating Classroom Activity with a Non-Linear, Multi-Display Presentation Tool

ERIC Educational Resources Information Center

Bligh, Brett; Coyle, Do

2013-01-01

This paper uses an Activity Theory framework to evaluate the use of a novel, multi-screen, non-linear presentation tool. The Thunder tool allows presenters to manipulate and annotate multiple digital slides and to concurrently display a selection of juxtaposed resources across a wall-sized projection area. Conventional, single screen presentation…

Intention, Subjective Norms, and Cancer Screening in the Context of Relational Culture

ERIC Educational Resources Information Center

Pasick, Rena J.; Barker, Judith C.; Otero-Sabogal, Regina; Burke, Nancy J.; Joseph, Galen; Guerra, Claudia

2009-01-01

Research targeting disparities in breast cancer detection has mainly utilized theories that do not account for social context and culture. Most mammography promotion studies have used a conceptual framework centered in the cognitive constructs of intention (commonly regarded as the most important determinant of screening behavior), self-efficacy,…

Construction of robust prognostic predictors by using projective adaptive resonance theory as a gene filtering method.

PubMed

Takahashi, Hiro; Kobayashi, Takeshi; Honda, Hiroyuki

2005-01-15

For establishing prognostic predictors of various diseases using DNA microarray analysis technology, it is desired to find selectively significant genes for constructing the prognostic model and it is also necessary to eliminate non-specific genes or genes with error before constructing the model. We applied projective adaptive resonance theory (PART) to gene screening for DNA microarray data. Genes selected by PART were subjected to our FNN-SWEEP modeling method for the construction of a cancer class prediction model. The model performance was evaluated through comparison with a conventional screening signal-to-noise (S2N) method or nearest shrunken centroids (NSC) method. The FNN-SWEEP predictor with PART screening could discriminate classes of acute leukemia in blinded data with 97.1% accuracy and classes of lung cancer with 90.0% accuracy, while the predictor with S2N was only 85.3 and 70.0% or the predictor with NSC was 88.2 and 90.0%, respectively. The results have proven that PART was superior for gene screening. The software is available upon request from the authors. honda@nubio.nagoya-u.ac.jp

Generalized charge-screening in relativistic Thomas–Fermi model

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

Akbari-Moghanjoughi, M.

In this paper, we study the charge shielding within the relativistic Thomas-Fermi model for a wide range of electron number-densities and the atomic-number of screened ions. A generalized energy-density relation is obtained using the force-balance equation and taking into account the Chandrasekhar's relativistic electron degeneracy pressure. By numerically solving a second-order nonlinear differential equation, the Thomas-Fermi screening length is investigated, and the results are compared for three distinct regimes of the solid-density, warm-dense-matter, and white-dwarfs (WDs). It is revealed that our nonlinear screening theory is compatible with the exponentially decaying Thomas-Fermi-type shielding predicted by the linear response theory. Moreover, themore » variation of relative Thomas-Fermi screening length shows that extremely dense quantum electron fluids are relatively poor charge shielders. Calculation of the total number of screening electrons around a nucleus shows that there is a position of maximum number of screening localized electrons around the screened nucleus, which moves closer to the point-like nucleus by increase in the plasma number density but is unaffected due to increase in the atomic-number value. It is discovered that the total number of screening electrons, (N{sub s}∝r{sub TF}{sup 3}/r{sub d}{sup 3} where r{sub TF} and r{sub d} are the Thomas-Fermi and interparticle distance, respectively) has a distinct limit for extremely dense plasmas such as WD-cores and neutron star crusts, which is unique for all given values of the atomic-number. This is equal to saying that in an ultrarelativistic degeneracy limit of electron-ion plasma, the screening length couples with the system dimensionality and the plasma becomes spherically self-similar. Current analysis can provide useful information on the effects of relativistic correction to the charge screening for a wide range of plasma density, such as the inertial-confined plasmas and compact stellar objects.« less

Development of the multiple sclerosis (MS) early mobility impairment questionnaire (EMIQ).

PubMed

Ziemssen, Tjalf; Phillips, Glenn; Shah, Ruchit; Mathias, Adam; Foley, Catherine; Coon, Cheryl; Sen, Rohini; Lee, Andrew; Agarwal, Sonalee

2016-10-01

The Early Mobility Impairment Questionnaire (EMIQ) was developed to facilitate early identification of mobility impairments in multiple sclerosis (MS) patients. We describe the initial development of the EMIQ with a focus on the psychometric evaluation of the questionnaire using classical and item response theory methods. The initial 20-item EMIQ was constructed by clinical specialists and qualitatively tested among people with MS and physicians via cognitive interviews. Data from an observational study was used to make additional updates to the instrument based on exploratory factor analysis (EFA) and item response theory (IRT) analysis, and psychometric analyses were performed to evaluate the reliability and validity of the final instrument's scores and screening properties (i.e., sensitivity and specificity). Based on qualitative interview analyses, a revised 15-item EMIQ was included in the observational study. EFA, IRT and item-to-item correlation analyses revealed redundant items which were removed leading to the final nine-item EMIQ. The nine-item EMIQ performed well with respect to: test-retest reliability (ICC = 0.858); internal consistency (α = 0.893); convergent validity; and known-groups methods for construct validity. A cut-point of 41 on the 0-to-100 scale resulted in sufficient sensitivity and specificity statistics for viably identifying patients with mobility impairment. The EMIQ is a content valid and psychometrically sound instrument for capturing MS patients' experience with mobility impairments in a clinical practice setting. Additional research is suggested to further confirm the EMIQ's screening properties over time.

Collision time measurements in a sonoluminescing microplasma with a large plasma parameter.

PubMed

Bataller, A; Kappus, B; Camara, C; Putterman, S

2014-07-11

The plasma which forms inside of a micron-sized sonoluminescing bubble in water for under a nanosecond has been probed with 3 ns long laser pulses. A comparison of the response to 532 and 1064 nm light indicates that the plasma number density is about 2×10(21)  cm(-3) and that transport properties are dominated by strong screening and correlation effects. The spherical shape, well-defined atomic density, and blackbody temperature make the sonoluminescing plasma a test bed for theories of strongly coupled plasmas. The plasma in this experiment distinguishes between competing theories of strong, intermediate, and weak effective screening.

Collision Time Measurements in a Sonoluminescing Microplasma with a Large Plasma Parameter

NASA Astrophysics Data System (ADS)

Bataller, A.; Kappus, B.; Camara, C.; Putterman, S.

2014-07-01

The plasma which forms inside of a micron-sized sonoluminescing bubble in water for under a nanosecond has been probed with 3 ns long laser pulses. A comparison of the response to 532 and 1064 nm light indicates that the plasma number density is about 2×1021 cm-3 and that transport properties are dominated by strong screening and correlation effects. The spherical shape, well-defined atomic density, and blackbody temperature make the sonoluminescing plasma a test bed for theories of strongly coupled plasmas. The plasma in this experiment distinguishes between competing theories of strong, intermediate, and weak effective screening.

Ink Wash Painting Style Rendering With Physically-based Ink Dispersion Model

NASA Astrophysics Data System (ADS)

Wang, Yifan; Li, Weiran; Zhu, Qing

2018-04-01

This paper presents a real-time rendering method based on the GPU programmable pipeline for rendering the 3D scene in ink wash painting style. The method is divided into main three parts: First, render the ink properties of 3D model by calculating its vertex curvature. Then, cached the ink properties to a paper structure and using an ink dispersion model which is defined by referencing the theory of porous media to simulate the dispersion of ink. Finally, convert the ink properties to the pixel color information and render it to the screen. This method has a better performance than previous methods in visual quality.

Ferroionic states: coupling between surface electrochemical and bulk ferroelectric functionalities on the nanoscale.

NASA Astrophysics Data System (ADS)

Kalinin, Sergei

Ferroelectricity on the nanoscale has remained a subject of much fascination in condensed matter physics for the last several decades. It is well-recognized that stability of the ferroelectric state necessitates effective polarization screening, and hence screening mechanism and screening charge dynamics become strongly coupled to ferroelectric phase stability and domain behavior. Previously, the role of the screening charge in macroscopic ferroelectrics was observed in phenomena such as potential retention above Curie temperature, back switching of ferroelectric domains, and chaos and intermittency during domain switching. In the last several years, multiple reports claiming ferroelectricity in ultrathin ferroelectrics based on formation of remanent polarization states, local hysteresis loops, and pressure induced switching were made. However, similar phenomena were reported for traditionally non-ferroelectric materials, creating significant level of uncertainty in the field. We pose that in the nanoscale systems, the ferroelectric state is fundamentally inseparable from electrochemical state of the surface, leading to emergence of coupled electrochemical-ferroelectric states. I will present the results of experimental and theoretical work exploring the basic mechanisms of emergence of these coupled states including the basic theory and phase-field formulation for domain evolution. I further discuss the thermodynamics and thickness evolution of this state, and demonstrate the experimental pathway to establish its presence based on spectroscopic version of piezoresponse force microscopy. Finally, the role of chemical screening on domain dynamics is explored using phase-field modelling. This analysis reconciles multiple prior studies, and set forward the predictive pathways for new generations of ferroelectric devices and applications. This research was sponsored by the Division of Materials Sciences and Engineering, BES, DOE, and was conducted at the Center for Nanophase Materials Sciences, sponsored at Oak Ridge National Laboratory by the Scientific User Facilities Division.

Analyzing slug tests in wells screened across the watertable: A field assessment

USGS Publications Warehouse

Stanford, K.L.; McElwee, C.D.

2000-01-01

The slug test is the most widely used technique for the in situ estimation of hydraulic conductivity in confined and unconfined formations. Currently, there are no generally accepted methods in the groundwater literature for the analysis of response data from slug tests performed in wells screened across the watertable. A field study was undertaken in an attempt to develop a set of practical guidelines for tests conducted in such wells. Three wells, screened within unconsolidated material exhibiting a range of hydraulic conductivities (.05-30.0 m/day), were installed to depths of up to 9 m (30 ft) in Kansas River alluvium that ranges in thickness from 15 m to 21 m (50 ft to 70 ft) near Lawrence, Kansas. Intensive well-development efforts removed any drilling debris that could interfere with well-formation hydraulics. Once the wells were developed properly, a series of slug tests was performed at each well. The tests were designed to assess the role of the unsaturated zone and the appropriateness of assuming a fixed hydraulic head upper boundary. The results of this investigation can be summarized as follows: (1) the sufficiency of well development should be based on repeat slug tests and not the clarity of pumped water; (2) the effective screen radius for best model analysis should be based on a mass balance and not nominal screen dimensions; (3) the watertable can be represented as a constant head boundary and flow in the unsaturated zone can be ignored in most situations; (4) conventional techniques for the analysis of slug-test data seem to be reasonable for slug tests conducted in wells screened across the watertable, when used with the appropriate effective screen radius and normalized head range; and (5) fluctuations in the watertable elevation through time can be exploited to obtain some insight into the nature of vertical variation in hydraulic conductivity at a well. The results of this investigation indicate that multiple slug tests should be performed at wells screened across the watertable in order to reliably assess the sufficiency of well development and the appropriateness of conventional theory. ?? 2000 International Association for Mathematical Geology.

Partnership for Healthier Asians: Disseminating Evidence-Based Practices in Asian-American Communities Using a Market-Oriented and Multilevel Approach.

PubMed

Kim, Karen; Quinn, Michael; Chandrasekar, Edwin; Patel, Reena; Lam, Helen

2016-06-16

One of the greatest challenges facing health promotion and disease prevention is translating research findings into evidence-based practices (EBP). There is currently a limited research base to inform the design of dissemination action plans, especially within medically underserved communities. The objective of this paper is to describe an innovative study protocol to disseminate colorectal cancer (CRC) screening guidelines in seven Asian subgroups. This study integrated a market-oriented Push-Pull-Infrastructure Model, Diffusion of Innovation Theory, and community-based participatory research approach to create a community-centered dissemination framework. Consumer research, through focus groups and community-wide surveys, was centered on the adopters to ensure a multilevel intervention was well designed and effective. Collaboration took place between an academic institution and eight community-based organizations. These groups worked together to conduct thorough consumer research. A sample of 72 Asian Americans participated in 8 focus groups, and differences were noted across ethnic groups. Furthermore, 464 community members participated in an Individual Client Survey. Most participants agreed that early detection of cancer was important (434/464, 93.5%), cancer could happen to anyone (403/464, 86.9%), CRC could be prevented (344/464, 74.1%), and everyone should screen for CRC (389/464, 83.8%). However, 35.8% (166/464) of participants also felt that people were better off not knowing it they had cancer, and 45.5% (211/464) would screen only when they had symptoms. Most participants indicated that they would screen upon their doctor's recommendation, but half reported that they only saw a doctor when they were sick. Data collection currently is underway for a multilevel intervention (community health advisor and social marketing campaign) and will conclude March 2016. We expect that analysis and results will be available by June 2016. This study outlines a complementary role for researchers and community organizations in disseminating EBP, and incorporates social interactions and influences to move individuals from simple awareness to decisions towards positive action.

Screen-time Weight-loss Intervention Targeting Children at Home (SWITCH): A randomized controlled trial study protocol

PubMed Central

2011-01-01

Background Approximately one third of New Zealand children and young people are overweight or obese. A similar proportion (33%) do not meet recommendations for physical activity, and 70% do not meet recommendations for screen time. Increased time being sedentary is positively associated with being overweight. There are few family-based interventions aimed at reducing sedentary behavior in children. The aim of this trial is to determine the effects of a 24 week home-based, family oriented intervention to reduce sedentary screen time on children's body composition, sedentary behavior, physical activity, and diet. Methods/Design The study design is a pragmatic two-arm parallel randomized controlled trial. Two hundred and seventy overweight children aged 9-12 years and primary caregivers are being recruited. Participants are randomized to intervention (family-based screen time intervention) or control (no change). At the end of the study, the control group is offered the intervention content. Data collection is undertaken at baseline and 24 weeks. The primary trial outcome is child body mass index (BMI) and standardized body mass index (zBMI). Secondary outcomes are change from baseline to 24 weeks in child percentage body fat; waist circumference; self-reported average daily time spent in physical and sedentary activities; dietary intake; and enjoyment of physical activity and sedentary behavior. Secondary outcomes for the primary caregiver include change in BMI and self-reported physical activity. Discussion This study provides an excellent example of a theory-based, pragmatic, community-based trial targeting sedentary behavior in overweight children. The study has been specifically designed to allow for estimation of the consistency of effects on body composition for Māori (indigenous), Pacific and non-Māori/non-Pacific ethnic groups. If effective, this intervention is imminently scalable and could be integrated within existing weight management programs. Trial Registration ACTRN12611000164998 PMID:21718543

Interactive, culturally sensitive education on colorectal cancer screening.

PubMed

Menon, Usha; Szalacha, Laura A; Belue, Rhonda; Rugen, Kathryn; Martin, Kelly R; Kinney, Anita Y

2008-09-01

Increasing colorectal cancer screening (CRCS) can have a substantial positive impact on morbidity and mortality. The purpose of this report is to describe the development and feasibility testing of a computer-based, theory-guided educational program designed to increase CRCS. This mixed-methods study used focus groups and subsequent randomized controlled trial design. Participants (N = 199) were randomized to an intervention or control group; 75% were African American; mean age was 57.36 (SD = 6.8); 71% were male. Previously validated measures on knowledge, beliefs, and screening test adherence were used to establish pre- and post-intervention perceptions. Feasibility was measured by response and completion rates, and participants' perceptions of the program. Before feasibility testing, the program was presented to 2 focus groups. Changes were made to the program based on discussion, leading to a visually appealing, easy to understand and navigate, self-paced program. In the RCT pilot test that followed, of the participants in the intervention group, 80% said the education helped them decide to get CRCS; 49% agreed it helped them overcome barriers; 91% agreed it was useful, 68% thought it raised new concerns about cancer, but only 30% said it made them worry about CRC; 95% agreed their doctor's office should continue giving such education, and 99% said they would inform family about the program. The response rate of 83% demonstrated feasibility of conducting colorectal cancer education in the primary care setting; overall the program was well received; participants averaged 23 minutes to complete it. Participants sought no help from attending data collectors and navigated the revised touch screen program with ease. Computer-based education is feasible in primary care clinics.

Molecular – genetic variance of RH blood group system within human population of Bosnia and Herzegovina

PubMed Central

Lasić, Lejla; Lojo-Kadrić, Naida; Silajdžić, Elma; Pojskić, Lejla; Hadžiselimović, Rifat; Pojskić, Naris

2013-01-01

There are two major theories for inheritance of Rh blood group system: Fisher – Race theory and Wiener theory. Aim of this study was identifying frequency of RHDCE alleles in Bosnian – Herzegovinian population and introduction of this method in screening for Rh phenotype in B&H since this type of analysis was not used for blood typing in B&H before. Rh blood group was typed by Polymerase Chain Reaction, using the protocols and primers previously established by other authors, then carrying out electrophoresis in 2-3% agarose gel. Percentage of Rh positive individuals in our sample is 84.48%, while the percentage of Rh negative individuals is 15.52%. Inter-rater agreement statistic showed perfect agreement (K=1) between the results of Rh blood system detection based on serological and molecular-genetics methods. In conclusion, molecular – genetic methods are suitable for prenatal genotyping and specific cases while standard serological method is suitable for high-throughput of samples. PMID:23448604

Cognitive Load Theory--Sometimes Less Is More

ERIC Educational Resources Information Center

Taylor, Cody

2013-01-01

The following paper represents review of the literature examining the current research related to cognitive load theory and more specifically the negative aspects of the redundant on-screen text. The authors describe working and long-term memory and how both factor into human learning through the facilitation of knowledge transfer. Limited working…

Cultural Context and Modification of Behavior Change Theory

ERIC Educational Resources Information Center

Sanders Thompson, Vetta L.

2009-01-01

Although social and cultural contexts act on each level of the multilevel ecologic model to affect cancer risk, health behavior, and cancer screening and promotion in health behavior research, people have yet to develop theories that sufficiently integrate the social and environmental context with group and individual behavior. The "Behavioral…

Performance and Self-Consistency of the Generalized Dielectric Dependent Hybrid Functional

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

Brawand, Nicholas P.; Govoni, Marco; Vörös, Márton

Here, we analyze the performance of the recently proposed screened exchange constant functional (SX) on the GW100 test set, and we discuss results obtained at different levels of self-consistency. The SX functional is a generalization of dielectric dependent hybrid functionals to finite systems; it is nonempirical and depends on the average screening of the exchange interaction. We compare results for ionization potentials obtained with SX to those of CCSD(T) calculations and experiments, and we find excellent agreement, on par with recent state of the art methods based on many body perturbation theory. Applying SX perturbatively to correct PBE eigenvalues yieldsmore » improved results in most cases, except for ionic molecules, for which wave function self-consistency is instead crucial. Calculations where wave functions and the screened exchange constant (α SX) are determined self-consistently, and those where α SX is fixed to the value determined within PBE, yield results of comparable accuracy. Perturbative G 0W 0 corrections of eigenvalues obtained with self-consistent αSX are small on average, for all molecules in the GW100 test set.« less

Performance and Self-Consistency of the Generalized Dielectric Dependent Hybrid Functional

DOE PAGES

Brawand, Nicholas P.; Govoni, Marco; Vörös, Márton; ...

2017-05-24

Here, we analyze the performance of the recently proposed screened exchange constant functional (SX) on the GW100 test set, and we discuss results obtained at different levels of self-consistency. The SX functional is a generalization of dielectric dependent hybrid functionals to finite systems; it is nonempirical and depends on the average screening of the exchange interaction. We compare results for ionization potentials obtained with SX to those of CCSD(T) calculations and experiments, and we find excellent agreement, on par with recent state of the art methods based on many body perturbation theory. Applying SX perturbatively to correct PBE eigenvalues yieldsmore » improved results in most cases, except for ionic molecules, for which wave function self-consistency is instead crucial. Calculations where wave functions and the screened exchange constant (α SX) are determined self-consistently, and those where α SX is fixed to the value determined within PBE, yield results of comparable accuracy. Perturbative G 0W 0 corrections of eigenvalues obtained with self-consistent αSX are small on average, for all molecules in the GW100 test set.« less

On selecting satellite conjunction filter parameters

NASA Astrophysics Data System (ADS)

Alfano, Salvatore; Finkleman, David

2014-06-01

This paper extends concepts of signal detection theory to predict the performance of conjunction screening techniques and guiding the selection of keepout and screening thresholds. The most efficient way to identify satellites likely to collide is to employ filters to identify orbiting pairs that should not come close enough over a prescribed time period to be considered hazardous. Such pairings can then be eliminated from further computation to accelerate overall processing time. Approximations inherent in filtering techniques include screening using only unperturbed Newtonian two body astrodynamics and uncertainties in orbit elements. Therefore, every filtering process is vulnerable to including objects that are not threats and excluding some that are threats, Type I and Type II errors. The approach in this paper guides selection of the best operating point for the filters suited to a user's tolerance for false alarms and unwarned threats. We demonstrate the approach using three archetypal filters with an initial three-day span, select filter parameters based on performance, and then test those parameters using eight historical snapshots of the space catalog. This work provides a mechanism for selecting filter parameters but the choices depend on the circumstances.

A Peer Health Educator Program for Breast Cancer Screening Promotion: Arabic, Chinese, South Asian, and Vietnamese Immigrant Women's Perspectives

PubMed Central

Parascandalo, Faye

2015-01-01

This study explored Arabic, Chinese, South Asian, and Vietnamese immigrant women's experiences with a peer health educator program, a public health program that facilitated access to breast health information and mammography screening. Framed within critical social theory, this participatory action research project took place from July 2009 to January 2011. Ten focus groups and 14 individual interviews were conducted with 82 immigrant women 40 years of age and older. Qualitative methods were utilized. Thematic content analysis derived from grounded theory and other qualitative literature was employed to analyze data. Four dominant themes emerged: Breast Cancer Prevention focused on learning within the program, Social Support provided by the peer health educator and other women, Screening Services Access for Women centered on service provision, and Program Enhancements related to specific modifications required to meet the needs of immigrant women accessing the program. The findings provide insights into strategies used to promote breast health, mammography screening, and the improvement of public health programming. Perceived barriers that continue to persist are structural barriers, such as the provision of information on breast cancer and screening by family physicians. A future goal is to improve collaborations between public health and primary care to minimize this barrier. PMID:25810922

A Peer Health Educator Program for Breast Cancer Screening Promotion: Arabic, Chinese, South Asian, and Vietnamese Immigrant Women's Perspectives.

PubMed

Crawford, Joanne; Frisina, Angela; Hack, Tricia; Parascandalo, Faye

2015-01-01

This study explored Arabic, Chinese, South Asian, and Vietnamese immigrant women's experiences with a peer health educator program, a public health program that facilitated access to breast health information and mammography screening. Framed within critical social theory, this participatory action research project took place from July 2009 to January 2011. Ten focus groups and 14 individual interviews were conducted with 82 immigrant women 40 years of age and older. Qualitative methods were utilized. Thematic content analysis derived from grounded theory and other qualitative literature was employed to analyze data. Four dominant themes emerged: Breast Cancer Prevention focused on learning within the program, Social Support provided by the peer health educator and other women, Screening Services Access for Women centered on service provision, and Program Enhancements related to specific modifications required to meet the needs of immigrant women accessing the program. The findings provide insights into strategies used to promote breast health, mammography screening, and the improvement of public health programming. Perceived barriers that continue to persist are structural barriers, such as the provision of information on breast cancer and screening by family physicians. A future goal is to improve collaborations between public health and primary care to minimize this barrier.

Reconsidering inequalities in preventive health care: an application of cultural health capital theory and the life-course perspective to the take-up of mammography screening.

PubMed

Missinne, Sarah; Neels, Karel; Bracke, Piet

2014-11-01

While there are abundant descriptions of socioeconomic inequalities in preventive health care, knowledge about the true mechanisms is still lacking. Recently, the role of cultural health capital in preventive health-care inequalities has been discussed theoretically. Given substantial analogies, we explore how our understanding of cultural health capital and preventive health-care inequalities can be advanced by applying the theoretical principles and methodology of the life-course perspective. By means of event history analysis and retrospective data from the Survey of Health Ageing and Retirement, we examine the role of cultural capital and cultural health capital during childhood on the timely initiation of mammography screening in Belgium (N = 1348). In line with cumulative disadvantage theory, the results show that childhood cultural conditions are independently associated with mammography screening, even after childhood and adulthood socioeconomic position and health are controlled for. Lingering effects from childhood are suggested by the accumulation of cultural health capital that starts early in life. Inequalities in the take-up of screening are manifested as a lower probability of ever having a mammogram, rather than in the late initiation of screening. © 2014 The Authors. Sociology of Health & Illness © 2014 Foundation for the Sociology of Health & Illness/John Wiley & Sons Ltd.

Effect of Ionic Correlations on the Surface Forces in Thin Liquid Films: Influence of Multivalent Coions and Extended Theory

PubMed Central

Danov, Krassimir D.; Basheva, Elka S.; Kralchevsky, Peter A.

2016-01-01

Experimental data for the disjoining pressure of foam films stabilized by anionic surfactant in the presence of 1:1, 1:2, 1:3, and 2:2 electrolytes: NaCl, Na2SO4, Na3Citrate, and MgSO4 are reported. The disjoining pressure predicted by the Derjaguin-Landau-Verwey-Overbeek (DLVO) theory coincides with the experimental data in the case of a 1:1 electrolyte, but it is considerably greater than the measured pressure in all other cases. The theory is extended to account for the effects of ionic correlations and finite ionic radii. Original analytical expressions are derived for the local activity coefficient, electrostatic disjoining pressure, and asymptotic screening parameter. With the same parameter of counterion binding as for a 1:1 electrolyte, the curves predicted by the extended theory are in perfect agreement with the experimental data for 1:2 and 1:3 electrolytes. In comparison with the DLVO theory, the effect of ionic correlations leads to more effective screening of electrostatic interactions, and lower electric potential and counterion concentrations in the film’s midplane, resulting in lower disjoining pressure, as experimentally observed. The developed theory is applicable to both multivalent coions and multivalent counterions. Its application could remove some discrepancies between theory and experiment observed in studies with liquid films from electrolyte solutions. PMID:28773269

Many-body theory of electrical, thermal and optical response of molecular heterojunctions

NASA Astrophysics Data System (ADS)

Bergfield, Justin Phillip

In this work, we develop a many-body theory of electronic transport through single molecule junctions based on nonequilibrium Green's functions (NEGFs). The central quantity of this theory is the Coulomb self-energy matrix of the junction SigmaC. SigmaC is evaluated exactly in the sequential-tunneling limit, and the correction due to finite lead-molecule tunneling is evaluated using a conserving approximation based on diagrammatic perturbation theory on the Keldysh contour. In this way, tunneling processes are included to infinite order, meaning that any approximation utilized is a truncation in the physical processes considered rather than in the order of those processes. Our theory reproduces the key features of both the Coulomb blockade and coherent transport regimes simultaneously in a single unified theory. Nonperturbative effects of intramolecular correlations are included, which are necessary to accurately describe the highest occupied molecular orbital (HOMO)-lowest unoccupied molecular orbital (LUMO) gap, essential for a quantitative theory of transport. This work covers four major topics related to transport in single-molecule junctions. First, we use our many-body theory to calculate the nonlinear electrical response of the archetypal Au-1,4-benzenedithiol-Au junction and find irregularly shaped 'molecular diamonds' which have been experimentally observed in some larger molecules but which are inaccessible to existing theoretical approaches. Next, we extend our theory to include heat transport and develop an exact expression for the heat current in an interacting nanostructure. Using this result, we discover that quantum coherence can strongly enhance the thermoelectric response of a device, a result with a number of technological applications. We then develop the formalism to include multi-orbital lead-molecule contacts and multi-channel leads, both of which strongly affect the observable transport. Lastly, we include a dynamic screening correction to Sigma C and investigate the optoelectric response of several molecular junctions.

Electrostatic analogy for symmetron gravity

NASA Astrophysics Data System (ADS)

Ogden, Lillie; Brown, Katherine; Mathur, Harsh; Rovelli, Kevin

2017-12-01

The symmetron model is a scalar-tensor theory of gravity with a screening mechanism that suppresses the effect of the symmetron field at high densities characteristic of the Solar System and laboratory scales but allows it to act with gravitational strength at low density on the cosmological scale. We elucidate the screening mechanism by showing that in the quasistatic Newtonian limit there are precise analogies between symmetron gravity and electrostatics for both strong and weak screening. For strong screening we find that large dense bodies behave in a manner analogous to perfect conductors in electrostatics. Based on this analogy we find that the symmetron field exhibits a lightning rod effect wherein the field gradients are enhanced near the ends of pointed or elongated objects. An ellipsoid placed in a uniform symmetron gradient is shown to experience a torque. By symmetry there is no gravitational torque in this case. Hence this effect unmasks the symmetron and might serve as the basis for future laboratory experiments. The symmetron force between a point mass and a large dense body includes a component corresponding to the interaction of the point mass with its image in the larger body. None of these effects have counterparts in the Newtonian limit of Einstein gravity. We discuss the similarities between symmetron gravity and the chameleon model as well as the differences between the two.

Are Brief Alcohol Interventions Adequately Embedded in UK Primary Care? A Qualitative Study Utilising Normalisation Process Theory.

PubMed

O'Donnell, Amy; Kaner, Eileen

2017-03-28

Despite substantial evidence for their effectiveness, the adoption of alcohol screening and brief interventions (ASBI) in routine primary care remains inconsistent. Financial incentive schemes were introduced in England between 2008 and 2015 to encourage their delivery. We used Normalisation Process Theory-informed interviews to understand the barriers and facilitators experienced by 14 general practitioners (GPs) as they implemented ASBI during this period. We found multiple factors shaped provision. GPs were broadly cognisant and supportive of preventative alcohol interventions (coherence) but this did not necessarily translate into personal investment in their delivery (cognitive participation). This lack of investment shaped how GPs operationalised such "work" in day-to-day practice (collective action), with ASBI mostly delegated to nurses, and GPs reverting to "business as usual" in their management and treatment of problem drinking (reflexive monitoring). We conclude there has been limited progress towards the goal of an effectively embedded preventative alcohol care pathway in English primary care. Future policy should consider screening strategies that prioritise patients with conditions with a recognised link with excessive alcohol consumption, and which promote more efficient identification of the most problematic drinkers. Improved GP training to build skills and awareness of evidence-based ASBI tools could also help embed best practice over time.

Effects of Equilibrium Toroidal Flow on Locked Mode and Plasma Response in a Tokamak

NASA Astrophysics Data System (ADS)

Zhu, Ping; Huang, Wenlong; Yan, Xingting

2016-10-01

It is widely believed that plasma flow plays significant roles in regulating the processes of mode locking and plasma response in a tokamak in presence of external resonant magnetic perturbations (RMPs). Recently a common analytic relation for both locked mode and plasma response has been developed based on the steady-state solution to the coupled dynamic system of magnetic island evolution and torque balance. The analytic relation predicts the size of the magnetic island of a locked mode or a static nonlinear plasma response for a given RMP amplitude, and rigorously proves a screening effect of the equilibrium toroidal flow. To test the theory, we solve for the locked mode and the nonlinear plasma response in presence of RMP for a circular-shaped limiter tokamak equilibrium with constant toroidal flow, using the initial-value, full MHD simulation code NIMROD. The comparison between the simulation results and the theory prediction, in terms of the quantitative screening effects of equilibrium toroidal flow, will be reported and discussed. Supported by National Magnetic Confinement Fusion Science Program of China Grants 2014GB124002 and 2015GB101004, the 100 Talent Program of the Chinese Academy of Sciences, and U.S. Department of Energy Grants DE-FG02-86ER53218 and DE-FC02-08ER54975.

Computer Aided Drug Design: Success and Limitations.

PubMed

Baig, Mohammad Hassan; Ahmad, Khurshid; Roy, Sudeep; Ashraf, Jalaluddin Mohammad; Adil, Mohd; Siddiqui, Mohammad Haris; Khan, Saif; Kamal, Mohammad Amjad; Provazník, Ivo; Choi, Inho

2016-01-01

Over the last few decades, computer-aided drug design has emerged as a powerful technique playing a crucial role in the development of new drug molecules. Structure-based drug design and ligand-based drug design are two methods commonly used in computer-aided drug design. In this article, we discuss the theory behind both methods, as well as their successful applications and limitations. To accomplish this, we reviewed structure based and ligand based virtual screening processes. Molecular dynamics simulation, which has become one of the most influential tool for prediction of the conformation of small molecules and changes in their conformation within the biological target, has also been taken into account. Finally, we discuss the principles and concepts of molecular docking, pharmacophores and other methods used in computer-aided drug design.

Metacognitive Theory and Levels of History Department Students, Karabuk University

ERIC Educational Resources Information Center

Candan, Ahmet Sait

2012-01-01

This paper aims to study the levels of metacognition of students of History Department of Karabuk University and whether they differ according to their variables terms. Screening model was used in this study. Basic information about the concept of metacognition and metacognitive theory from movement of national and international literature were…

Theory Building through Qualitative Research: Marshalling Opportunities to Advance Cancer Screening Efforts

ERIC Educational Resources Information Center

Hay, Jennifer L.; Craddock Lee, Simon J.

2009-01-01

Many researchers lack the resources, time, and/or expertise to include qualitative strategies in their research. In recent years, substantive progress has been made among qualitative methodologists themselves to codify and systematize concept construction and typologies in qualitatively derived theory. These authors discuss the work of Rena Pasick…

The viscosity to entropy ratio: From string theory motivated bounds to warm dense matter

DOE PAGES

Faussurier, G.; Libby, S. B.; Silvestrelli, P. L.

2014-07-04

Here, we study the ratio of viscosity to entropy density in Yukawa one-component plasmas as a function of coupling parameter at fixed screening, and in realistic warm dense matter models as a function of temperature at fixed density. In these two situations, the ratio is minimized for values of the coupling parameters that depend on screening, and for temperatures that in turn depend on density and material. In this context, we also examine Rosenfeld arguments relating transport coefficients to excess reduced entropy for Yukawa one-component plasmas. For these cases we show that this ratio is always above the lower-bound conjecturemore » derived from string theory ideas.« less

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

Winther, Hans A.; Koyama, Kazuya; Wright, Bill S.

We present a general parallelized and easy-to-use code to perform numerical simulations of structure formation using the COLA (COmoving Lagrangian Acceleration) method for cosmological models that exhibit scale-dependent growth at the level of first and second order Lagrangian perturbation theory. For modified gravity theories we also include screening using a fast approximate method that covers all the main examples of screening mechanisms in the literature. We test the code by comparing it to full simulations of two popular modified gravity models, namely f ( R ) gravity and nDGP, and find good agreement in the modified gravity boost-factors relative tomore » ΛCDM even when using a fairly small number of COLA time steps.« less

Strong Quantum Coherence between Fermi Liquid Mahan Excitons

NASA Astrophysics Data System (ADS)

Paul, J.; Stevens, C. E.; Liu, C.; Dey, P.; McIntyre, C.; Turkowski, V.; Reno, J. L.; Hilton, D. J.; Karaiskaj, D.

2016-04-01

In modulation doped quantum wells, the excitons are formed as a result of the interactions of the charged holes with the electrons at the Fermi edge in the conduction band, leading to the so-called "Mahan excitons." The binding energy of Mahan excitons is expected to be greatly reduced and any quantum coherence destroyed as a result of the screening and electron-electron interactions. Surprisingly, we observe strong quantum coherence between the heavy hole and light hole excitons. Such correlations are revealed by the dominating cross-diagonal peaks in both one-quantum and two-quantum two-dimensional Fourier transform spectra. Theoretical simulations based on the optical Bloch equations where many-body effects are included phenomenologically reproduce well the experimental spectra. Time-dependent density functional theory calculations provide insight into the underlying physics and attribute the observed strong quantum coherence to a significantly reduced screening length and collective excitations of the many-electron system.

Strong Quantum Coherence between Fermi Liquid Mahan Excitons.

PubMed

Paul, J; Stevens, C E; Liu, C; Dey, P; McIntyre, C; Turkowski, V; Reno, J L; Hilton, D J; Karaiskaj, D

2016-04-15

In modulation doped quantum wells, the excitons are formed as a result of the interactions of the charged holes with the electrons at the Fermi edge in the conduction band, leading to the so-called "Mahan excitons." The binding energy of Mahan excitons is expected to be greatly reduced and any quantum coherence destroyed as a result of the screening and electron-electron interactions. Surprisingly, we observe strong quantum coherence between the heavy hole and light hole excitons. Such correlations are revealed by the dominating cross-diagonal peaks in both one-quantum and two-quantum two-dimensional Fourier transform spectra. Theoretical simulations based on the optical Bloch equations where many-body effects are included phenomenologically reproduce well the experimental spectra. Time-dependent density functional theory calculations provide insight into the underlying physics and attribute the observed strong quantum coherence to a significantly reduced screening length and collective excitations of the many-electron system.

Computational Screening of 2D Materials for Photocatalysis.

PubMed

Singh, Arunima K; Mathew, Kiran; Zhuang, Houlong L; Hennig, Richard G

2015-03-19

Two-dimensional (2D) materials exhibit a range of extraordinary electronic, optical, and mechanical properties different from their bulk counterparts with potential applications for 2D materials emerging in energy storage and conversion technologies. In this Perspective, we summarize the recent developments in the field of solar water splitting using 2D materials and review a computational screening approach to rapidly and efficiently discover more 2D materials that possess properties suitable for solar water splitting. Computational tools based on density-functional theory can predict the intrinsic properties of potential photocatalyst such as their electronic properties, optical absorbance, and solubility in aqueous solutions. Computational tools enable the exploration of possible routes to enhance the photocatalytic activity of 2D materials by use of mechanical strain, bias potential, doping, and pH. We discuss future research directions and needed method developments for the computational design and optimization of 2D materials for photocatalysis.

Quantifying Intrinsic Specificity: A Potential Complement to Affinity in Drug Screening

NASA Astrophysics Data System (ADS)

Wang, Jin; Zheng, Xiliang; Yang, Yongliang; Drueckhammer, Dale; Yang, Wei; Verkhivker, Gennardy; Wang, Erkang

2007-11-01

We report here the investigation of a novel description of specificity in protein-ligand binding based on energy landscape theory. We define a new term, intrinsic specificity ratio (ISR), which describes the level of discrimination in binding free energies of the native basin for a protein-ligand complex from the weaker binding states of the same ligand. We discuss the relationship between the intrinsic specificity we defined here and the conventional definition of specificity. In a docking study of molecules with the enzyme COX-2, we demonstrate a statistical correspondence between ISR value and geometrical shapes of the small molecules binding to COX-2. We further observe that the known selective (nonselective) inhibitors of COX-2 have higher (lower) ISR values. We suggest that intrinsic specificity ratio may be a useful new criterion and a complement to affinity in drug screening and in searching for potential drug lead compounds.

Rate of Bubble Coalescence following Quasi-Static Approach: Screening and Neutralization of the Electric Double Layer

PubMed Central

Katsir, Yael; Marmur, Abraham

2014-01-01

Air-bubble coalescence in aqueous electrolytic solutions, following quasi-static approach, was studied in order to understand its slow rate in purified water and high rate in electrolytic solutions. The former is found to be due to surface charges, originating from the speciation of dissolved CO2, which sustain the electric double layer repulsion. Rapid coalescence in electrolytic solutions is shown to occur via two different mechanisms: (1) neutralization of the carbonaceous, charged species by acids; or (2) screening of the repulsive charge effects by salts and bases. The results do not indicate any ion specificity. They can be explained within the DLVO theory for the van der Waals and electric double layer interactions between particles, in contrast to observations of coalescence following dynamic approach. The present conclusions should serve as a reference point to understanding the dynamic behavior. PMID:24589528

Integrating Men’s Health and Masculinity Theories to Explain Colorectal Cancer Screening Behavior

PubMed Central

Christy, Shannon M.; Mosher, Catherine E.; Rawl, Susan M.

2013-01-01

Colorectal cancer (CRC) is the third most common cause of cancer deaths among men in the United States. Although CRC screening has been found to reduce CRC incidence and mortality, current screening rates among men are suboptimal due to various practical and psychosocial barriers. One potential barrier to CRC screening identified in qualitative studies with men is the threat to masculinity that endoscopic screening methods pose. Indeed, beliefs about masculinity have been predictive of other preventive health behaviors among men. In this review paper, we propose a novel conceptual framework to explain men’s CRC screening behavior that integrates masculinity norms, gender role conflict, men’s health care experiences, behaviors, and beliefs, and social and background variables. This framework has the potential to guide future research on men’s CRC screening behaviors and other health behaviors and may inform gender-sensitive interventions which target masculinity beliefs to increase preventive health behaviors. PMID:23813927

Integrating men's health and masculinity theories to explain colorectal cancer screening behavior.

PubMed

Christy, Shannon M; Mosher, Catherine E; Rawl, Susan M

2014-01-01

Colorectal cancer (CRC) is the third most common cause of cancer deaths among men in the United States. Although CRC screening has been found to reduce CRC incidence and mortality, current screening rates among men are suboptimal due to various practical and psychosocial barriers. One potential barrier to CRC screening identified in qualitative studies with men is the threat to masculinity that endoscopic screening methods pose. Indeed, beliefs about masculinity have been predictive of other preventive health behaviors among men. In this review article, we propose a novel conceptual framework to explain men's CRC screening behavior that integrates masculinity norms, gender role conflict, men's health care experiences, behaviors, and beliefs, and social and background variables. This framework has the potential to guide future research on men's CRC screening behaviors and other health behaviors and may inform gender-sensitive interventions that target masculinity beliefs to increase preventive health behaviors.

Comprehensive development and testing of the ASIST-GBV, a screening tool for responding to gender-based violence among women in humanitarian settings.

PubMed

Wirtz, A L; Glass, N; Pham, K; Perrin, N; Rubenstein, L S; Singh, S; Vu, A

2016-01-01

Conflict affected refugees and internally displaced persons (IDPs) are at increased vulnerability to gender-based violence (GBV). Health, psychosocial, and protection services have been implemented in humanitarian settings, but GBV remains under-reported and available services under-utilized. To improve access to existing GBV services and facilitate reporting, the ASIST-GBV screening tool was developed and tested for use in humanitarian settings. This process was completed in four phases: 1) systematic literature review, 2) qualitative research that included individual interviews and focus groups with GBV survivors and service providers, respectively, 3) pilot testing of the developed screening tool, and 4) 3-month implementation testing of the screening tool. Research was conducted among female refugees, aged ≥15 years in Ethiopia, and female IDPs, aged ≥18 years in Colombia. The systematic review and meta-analysis identified a range of GBV experiences and estimated a 21.4 % prevalence of sexual violence (95 % CI:14.9-28.7) among conflict-affected populations. No existing screening tools for GBV in humanitarian settings were identified. Qualitative research with GBV survivors in Ethiopia and Colombia found multiple forms of GBV experienced by refugees and IDPs that occurred during conflict, in transit, and in displaced settings. Identified forms of violence were combined into seven key items on the screening tool: threats of violence, physical violence, forced sex, sexual exploitation, forced pregnancy, forced abortion, and early or forced marriage. Cognitive testing further refined the tool. Pilot testing in both sites demonstrated preliminary feasibility where 64.8 % of participants in Ethiopia and 44.9 % of participants in Colombia were identified with recent (last 12 months) cases of GBV. Implementation testing of the screening tool, conducted as a routine service in camp/district hospitals, allowed for identification of GBV cases and referrals to services. In this phase, 50.6 % of participants in Ethiopia and 63.4 % in Colombia screened positive for recent experiences of GBV. Psychometric testing demonstrated appropriate internal consistency of the tool (Cronbach's α = 0.77) and item response theory demonstrated appropriate discrimination and difficulty of the tool. The ASIST-GBV screening tool has demonstrated utility and validity for use in confidential identification and referral of refugees and IDPs who experience GBV.

Interpretation of screen factor measurements

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

Lim, T.; Uhl, J.T.; Prud'Homme, R.K.

1983-08-01

Screen viscometer measurements give different information about polymer molecular weight and molecular weight distribution than intrinsic viscosity or relative viscosity measurements. This study shows that conventional screen viscometers measure elongation flow properties of solutions, and that for flexible polymers such as polyacrylamides, a sharp transition in conformation from a coiled to a stretched state is observed, which occurs at a Deborah number of 0.5. Conventional screen viscometers operate just above this critical Deborah number. Evidence for this transition in polymer conformation comes from measurements on a modified screen viscometer, from extensive work by Durst and Interhal on the sudden pressuremore » jumps during flow of polyacrylamide solutions through porous media, and from polymer kinetic theory modeling of molecular deformation in flow. ll references.« less

Latino Men and Familial Risk Communication about Prostate Cancer

PubMed Central

Hicks, Elisabeth M.; Litwin, Mark S.; Maliski, Sally L.

2014-01-01

Purpose This study investigated how familial communication about prostate cancer risk and screening affects sons of men with prostate cancer. It is important to engage Latino families shared decision making toward early detection because first degree relatives of men with PCa are at heightened risk and Latino men are diagnosed at more advanced stages of disease than Non-Hispanic White men. Methods The team conducted semi-structured interviews with seventeen sons of PCa survivors. Eight participants completed a follow up interview an average of seven months later. Therefore, our sample includes twenty-five transcripts. The sons are Latinos living in Southern California. Data were analyzed with a mix of a priori topical codes and grounded theory techniques. Results Sons were under informed about both familial risk and screening options. They became sensitized to PCa, desired information, and held protective intentions. Hopeful intentions came up against cultural taboos around sex, reproductive health, and intimacy that limited discussions between fathers and sons. Fathers were a valued source of information, but play various roles, which affect sons’ screening intentions. Open communication between father and son promoted awareness of screening and familial risk. Discussion Uncertainty about familial risk and screening options, especially early detection strategies, was exacerbated by cultural taboos around PCa. Fathers could have been primary and credible advocates for shared decision making, but sons found it difficult to learn from their fathers’ experience. Nursing Implications Findings from our study can inform community based interventions with Latino families, help to culturally tailor health messaging, and sensitize clinicians to a group which needs concerted counseling about PCa risk and screening. PMID:25158656

Estimating the relative utility of screening mammography.

PubMed

Abbey, Craig K; Eckstein, Miguel P; Boone, John M

2013-05-01

The concept of diagnostic utility is a fundamental component of signal detection theory, going back to some of its earliest works. Attaching utility values to the various possible outcomes of a diagnostic test should, in principle, lead to meaningful approaches to evaluating and comparing such systems. However, in many areas of medical imaging, utility is not used because it is presumed to be unknown. In this work, we estimate relative utility (the utility benefit of a detection relative to that of a correct rejection) for screening mammography using its known relation to the slope of a receiver operating characteristic (ROC) curve at the optimal operating point. The approach assumes that the clinical operating point is optimal for the goal of maximizing expected utility and therefore the slope at this point implies a value of relative utility for the diagnostic task, for known disease prevalence. We examine utility estimation in the context of screening mammography using the Digital Mammographic Imaging Screening Trials (DMIST) data. We show how various conditions can influence the estimated relative utility, including characteristics of the rating scale, verification time, probability model, and scope of the ROC curve fit. Relative utility estimates range from 66 to 227. We argue for one particular set of conditions that results in a relative utility estimate of 162 (±14%). This is broadly consistent with values in screening mammography determined previously by other means. At the disease prevalence found in the DMIST study (0.59% at 365-day verification), optimal ROC slopes are near unity, suggesting that utility-based assessments of screening mammography will be similar to those found using Youden's index.

Intimate Partner Violence Programs in a Children's Hospital: Comprehensive Assessment Utilizing a Delphi Instrument.

PubMed

Randell, Kimberly A; Evans, Sarah E; O'Malley, Donna; Dowd, M Denise

2015-03-01

The purpose of this study was to conduct a baseline assessment of intimate partner violence (IPV) practices in a pediatric hospital system. The Delphi Instrument for Hospital-based Domestic Violence Programs was used to assess the structure and components of the hospital system's IPV practices. Through key stakeholder interviews, we also assessed IPV practices in individual patient care areas. Qualitative analysis of interview data used a grounded theory approach. The hospital scored 17 of 100 points on the Delphi instrument assessment. Key areas of weakness identified by the Delphi instrument and interviews included lack of coordinated provider training and evaluation of IPV-related processes and no standards for IPV screening, safety assessment, and documentation. Most interviewees supported addressing IPV; all identified barriers to IPV screening at individual provider and institutional levels. Institutional barriers included lack of a standardized response to IPV disclosure, need for individualized screening protocols for different patient care settings, lack of standardized provider training, concerns about overextending social work resources, and lack of resources for hospital staff experiencing vicarious trauma. Individual barriers included concern that screening may harm physician-patient-family relationships and the perception that physicians are unwilling to address psychosocial issues. The Delphi Instrument for Hospital-based Domestic Violence Programs identified weaknesses and key areas for improvement in IPV practices. Deficiencies revealed by the Delphi instrument were affirmed by individual interview results. Institutional and individual provider level barriers must be addressed to optimize IPV practices in a pediatric hospital system. Copyright © 2015 by the American Academy of Pediatrics.

Optical absorption in disordered monolayer molybdenum disulfide

NASA Astrophysics Data System (ADS)

Ekuma, C. E.; Gunlycke, D.

2018-05-01

We explore the combined impact of sulfur vacancies and electronic interactions on the optical properties of monolayer MoS2. First, we present a generalized Anderson-Hubbard Hamiltonian that accounts for both randomly distributed sulfur vacancies and the presence of dielectric screening within the material. Second, we parametrize this energy-dependent Hamiltonian from first-principles calculations based on density functional theory and the Green's function and screened Coulomb (GW) method. Third, we apply a first-principles-based many-body typical medium method to determine the single-particle electronic structure. Fourth, we solve the Bethe-Salpeter equation to obtain the charge susceptibility χ with its imaginary part being related to the absorbance A . Our results show that an increased vacancy concentration leads to decreased absorption both in the band continuum and from exciton states within the band gap. We also observe increased absorption below the band-gap threshold and present an expression, which describes Lifshitz tails, in excellent qualitative agreement with our numerical calculations. This latter increased absorption in the 1.0 -2.5 eV range makes defect engineering of potential interest for solar cell applications.

Genarris: Random generation of molecular crystal structures and fast screening with a Harris approximation

NASA Astrophysics Data System (ADS)

Li, Xiayue; Curtis, Farren S.; Rose, Timothy; Schober, Christoph; Vazquez-Mayagoitia, Alvaro; Reuter, Karsten; Oberhofer, Harald; Marom, Noa

2018-06-01

We present Genarris, a Python package that performs configuration space screening for molecular crystals of rigid molecules by random sampling with physical constraints. For fast energy evaluations, Genarris employs a Harris approximation, whereby the total density of a molecular crystal is constructed via superposition of single molecule densities. Dispersion-inclusive density functional theory is then used for the Harris density without performing a self-consistency cycle. Genarris uses machine learning for clustering, based on a relative coordinate descriptor developed specifically for molecular crystals, which is shown to be robust in identifying packing motif similarity. In addition to random structure generation, Genarris offers three workflows based on different sequences of successive clustering and selection steps: the "Rigorous" workflow is an exhaustive exploration of the potential energy landscape, the "Energy" workflow produces a set of low energy structures, and the "Diverse" workflow produces a maximally diverse set of structures. The latter is recommended for generating initial populations for genetic algorithms. Here, the implementation of Genarris is reported and its application is demonstrated for three test cases.

Computational screening of organic materials towards improved photovoltaic properties

NASA Astrophysics Data System (ADS)

Dai, Shuo; Olivares-Amaya, Roberto; Amador-Bedolla, Carlos; Aspuru-Guzik, Alan; Borunda, Mario

2015-03-01

The world today faces an energy crisis that is an obstruction to the development of the human civilization. One of the most promising solutions is solar energy harvested by economical solar cells. Being the third generation of solar cell materials, organic photovoltaic (OPV) materials is now under active development from both theoretical and experimental points of view. In this study, we constructed a parameter to select the desired molecules based on their optical spectra performance. We applied it to investigate a large collection of potential OPV materials, which were from the CEPDB database set up by the Harvard Clean Energy Project. Time dependent density functional theory (TD-DFT) modeling was used to calculate the absorption spectra of the molecules. Then based on the parameter, we screened out the top performing molecules for their potential OPV usage and suggested experimental efforts toward their synthesis. In addition, from those molecules, we summarized the functional groups that provided molecules certain spectrum capability. It is hoped that useful information could be mined out to provide hints to molecular design of OPV materials.

Structural and electronic properties of U{sub n}O{sub m} (n=1-3,m=1-3n) clusters: A theoretical study using screened hybrid density functional theory

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

Yang, Yu; Liu, Haitao; Zhang, Ping, E-mail: zhang-ping@iapcm.ac.cn

The structural and electronic properties of small uranium oxide clusters U{sub n}O{sub m} (n=1-3, m=1-3n) are systematically studied within the screened hybrid density functional theory. It is found that the formation of U–O–U bondings and isolated U–O bonds are energetically more stable than U–U bondings. As a result, no uranium cores are observed. Through fragmentation studies, we find that the U{sub n}O{sub m} clusters with the m/n ratio between 2 and 2.5 are very stable, hinting that UO{sub 2+x} hyperoxides are energetically stable. Electronically, we find that the O-2p states always distribute in the deep energy range, and the U-5fmore » states always distribute at the two sides of the Fermi level. The U-6d states mainly hybridize with the U-5f states in U-rich clusters, while hybridizing with O-2p states in O-rich clusters. Our work is the first one on the screened hybrid density functional theory level studying the atomic and electronic properties of the actinide oxide clusters.« less

Development and psychometric properties of the Suicidality of Adolescent Screening Scale (SASS) using Multidimensional Item Response Theory.

PubMed

Sukhawaha, Supattra; Arunpongpaisal, Suwanna; Hurst, Cameron

2016-09-30

Suicide prevention in adolescents by early detection using screening tools to identify high suicidal risk is a priority. Our objective was to build a multidimensional scale namely "Suicidality of Adolescent Screening Scale (SASS)" to identify adolescents at risk of suicide. An initial pool of items was developed by using in-depth interview, focus groups and a literature review. Initially, 77 items were administered to 307 adolescents and analyzed using the exploratory Multidimensional Item Response Theory (MIRT) to remove unnecessary items. A subsequent exploratory factor analysis revealed 35 items that collected into 4 factors: Stressors, Pessimism, Suicidality and Depression. To confirm this structure, a new sample of 450 adolescents were collected and confirmatory MIRT factor analysis was performed. The resulting scale was shown to be both construct valid and able to discriminate well between adolescents that had, and hadn't previous attempted suicide. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Ionic screening and dissociation are crucial for understanding chemical self-propulsion in polar solvents.

PubMed

Brown, Aidan T; Poon, Wilson C K; Holm, Christian; de Graaf, Joost

2017-02-08

Polar solvents like water support the bulk dissociation of themselves and their solutes into ions, and the re-association of these ions into neutral molecules in a dynamic equilibrium, e.g., H 2 O 2 ⇌ H + + HO 2 - . Using continuum theory, we study the influence of these association-dissociation reactions on the self-propulsion of colloids driven by surface chemical reactions (chemical swimmers). We find that association-dissociation reactions should have a strong influence on swimmers' behaviour, and therefore should be included in future modelling. In particular, such bulk reactions should permit charged swimmers to propel electrophoretically even if all species involved in the surface reactions are neutral. The bulk reactions also significantly modify the predicted speed of chemical swimmers propelled by ionic currents, by up to an order of magnitude. For swimmers whose surface reactions produce both anions and cations (ionic self-diffusiophoresis), the bulk reactions produce an additional reactive screening length, analogous to the Debye length in electrostatics. This in turn leads to an inverse relationship between swimmer radius and swimming speed, which could provide an alternative explanation for recent experimental observations on Pt-polystyrene Janus swimmers [S. Ebbens et al., Phys. Rev. E: Stat., Nonlinear, Soft Matter Phys., 2012, 85, 020401]. We also use our continuum theory to investigate the effect of the Debye screening length itself, going beyond the infinitely-thin-screening-length approximation used by previous analytical theories. We identify significant departures from this limiting behaviour for micron-sized swimmers under typical experimental conditions and find that the approximation fails entirely for nanoscale swimmers.

3D pharmacophore-based virtual screening, docking and density functional theory approach towards the discovery of novel human epidermal growth factor receptor-2 (HER2) inhibitors.

PubMed

Gogoi, Dhrubajyoti; Baruah, Vishwa Jyoti; Chaliha, Amrita Kashyap; Kakoti, Bibhuti Bhushan; Sarma, Diganta; Buragohain, Alak Kumar

2016-12-21

Human epidermal growth factor receptor 2 (HER2) is one of the four members of the epidermal growth factor receptor (EGFR) family and is expressed to facilitate cellular proliferation across various tissue types. Therapies targeting HER2, which is a transmembrane glycoprotein with tyrosine kinase activity, offer promising prospects especially in breast and gastric/gastroesophageal cancer patients. Persistence of both primary and acquired resistance to various routine drugs/antibodies is a disappointing outcome in the treatment of many HER2 positive cancer patients and is a challenge that requires formulation of new and improved strategies to overcome the same. Identification of novel HER2 inhibitors with improved therapeutics index was performed with a highly correlating (r=0.975) ligand-based pharmacophore model (Hypo1) in this study. Hypo1 was generated from a training set of 22 compounds with HER2 inhibitory activity and this well-validated hypothesis was subsequently used as a 3D query to screen compounds in a total of four databases of which two were natural product databases. Further, these compounds were analyzed for compliance with Veber's drug-likeness rule and optimum ADMET parameters. The selected compounds were then subjected to molecular docking and Density Functional Theory (DFT) analysis to discern their molecular interactions at the active site of HER2. The findings thus presented would be an important starting point towards the development of novel HER2 inhibitors using well-validated computational techniques. Copyright © 2016 Elsevier Ltd. All rights reserved.

Understanding sustained domestic violence identification in maternal and child health nurse care: process evaluation from a 2-year follow-up of the MOVE trial.

PubMed

Hooker, Leesa; Small, Rhonda; Taft, Angela

2016-03-01

To investigate factors contributing to the sustained domestic violence screening and support practices of Maternal and Child Health nurses 2 years after a randomized controlled trial. Domestic violence screening by healthcare professionals has been implemented in many primary care settings. Barriers to screening exist and screening rates remain low. Evidence for longer term integration of nurse screening is minimal. Trial outcomes showed sustained safety planning behaviours by intervention group nurses. Process evaluation in 2-year follow-up of a cluster randomized controlled trial. Evaluation included a repeat online nurse survey and 14 interviews (July-September 2013). Survey analysis included comparison of proportionate group difference between arms and between trial baseline and 2 year follow-up surveys. Framework analysis was used to assess qualitative data. Normalization Process Theory informed evaluation design and interpretation of results. Survey response was 77% (n = 123/160). Sustainability of nurse identification of domestic violence appeared to be due to greater nurse discussion and domestic violence disclosure by women, facilitated by use of a maternal health and well-being checklist. Over time, intervention group nurses used the maternal checklist more at specific maternal health visits and found the checklist the most helpful resource assisting their domestic violence work. Nurses' spoke of a degree of 'normalization' to domestic violence screening that will need constant investment to maintain. Sustainable domestic violence screening and support outcomes can be achieved in an environment of comprehensive, nurse designed and theory driven implementation. Continuing training, discussion and monitoring of domestic violence work is needed to retain sustainable practices. © 2015 John Wiley & Sons Ltd.

Screening for elevated levels of fear-avoidance beliefs regarding work or physical activities in people receiving outpatient therapy.

PubMed

Hart, Dennis L; Werneke, Mark W; George, Steven Z; Matheson, James W; Wang, Ying-Chih; Cook, Karon F; Mioduski, Jerome E; Choi, Seung W

2009-08-01

Screening people for elevated levels of fear-avoidance beliefs is uncommon, but elevated levels of fear could worsen outcomes. Developing short screening tools might reduce the data collection burden and facilitate screening, which could prompt further testing or management strategy modifications to improve outcomes. The purpose of this study was to develop efficient yet accurate screening methods for identifying elevated levels of fear-avoidance beliefs regarding work or physical activities in people receiving outpatient rehabilitation. A secondary analysis of data collected prospectively from people with a variety of common neuromusculoskeletal diagnoses was conducted. Intake Fear-Avoidance Beliefs Questionnaire (FABQ) data were collected from 17,804 people who had common neuromusculoskeletal conditions and were receiving outpatient rehabilitation in 121 clinics in 26 states (in the United States). Item response theory (IRT) methods were used to analyze the FABQ data, with particular emphasis on differential item functioning among clinically logical groups of subjects, and to identify screening items. The accuracy of screening items for identifying subjects with elevated levels of fear was assessed with receiver operating characteristic analyses. Three items for fear of physical activities and 10 items for fear of work activities represented unidimensional scales with adequate IRT model fit. Differential item functioning was negligible for variables known to affect functional status outcomes: sex, age, symptom acuity, surgical history, pain intensity, condition severity, and impairment. Items that provided maximum information at the median for the FABQ scales were selected as screening items to dichotomize subjects by high versus low levels of fear. The accuracy of the screening items was supported for both scales. This study represents a retrospective analysis, which should be replicated using prospective designs. Future prospective studies should assess the reliability and validity of using one FABQ item to screen people for high levels of fear-avoidance beliefs. The lack of differential item functioning in the FABQ scales in the sample tested in this study suggested that FABQ screening could be useful in routine clinical practice and allowed the development of single-item screening for fear-avoidance beliefs that accurately identified subjects with elevated levels of fear. Because screening was accurate and efficient, single IRT-based FABQ screening items are recommended to facilitate improved evaluation and care of heterogeneous populations of people receiving outpatient rehabilitation.

Development and implementation of a smartphone application to promote physical activity and reduce screen-time in adolescent boys.

PubMed

Lubans, David R; Smith, Jordan J; Skinner, Geoff; Morgan, Philip J

2014-01-01

To describe the development and implementation of a smartphone application (app) designed to promote physical activity and reduce screen-time in adolescent boys considered "at-risk" of obesity. An app was developed to support the delivery of a face-to-face school-based obesity prevention program known as the "Active Teen Leaders Avoiding Screen-time" (ATLAS) program. ATLAS was guided by self-determination theory and social cognitive theory and evaluated using a cluster randomized controlled trial with 361 boys (12.7 ± 0.5 years) in 14 secondary schools. Following the completion of the study, participants in the intervention group completed a process evaluation questionnaire and focus groups were conducted with 42 students to explore their general perceptions of the ATLAS program and their experience with the smartphone app. Barriers and challenges encountered in the development, implementation, and evaluation of the app are also described. Participation in the study was not contingent on ownership of a smartphone, but 70% of participants in the intervention group reported having access to a smartphone or tablet device. Focus group participants reported an enjoyment of the program, and felt that it had provided them with new skills, techniques, and routines for the future. However, their engagement with the smartphone app was limited, due to a variety of reasons. Barriers to the implementation and evaluation of the app included limited access to smartphone devices, technical problems with the push notifications, lack of access to usage data, and the challenges of maintaining participants' interest in using the app. Although participants reported high levels of satisfaction with the ATLAS program in general, the smartphone app was not used extensively. Additional strategies and features may be needed to enhance engagement in adolescent boys.

Vouchers versus Lotteries: What works best in promoting Chlamydia screening? A cluster randomised controlled trial

PubMed Central

Niza, Claudia; Rudisill, Caroline; Dolan, Paul

2014-01-01

In this cluster randomised trial (N=1060), we tested the impact of financial incentives (£5 voucher vs. £200 lottery) framed as a gain or loss to promote Chlamydia screening in students aged 18–24 years, mimicking the standard outreach approach to student in halls of residence. Compared to the control group (1.5%), the lottery increased screening to 2.8% and the voucher increased screening to 22.8%. Incentives framed as gains were marginally more effective (10.5%) that loss-framed incentives (7.1%). This work fundamentally contributes to the literature by testing the predictive validity of Prospect Theory to change health behaviour in the field. PMID:25061507

Psychometric Properties of a Scale to Assess Parental Self-Efficacy for Influencing Children's Dietary, Physical Activity, Sedentary, and Screen Time Behaviors in Disadvantaged Areas

ERIC Educational Resources Information Center

Norman, Åsa; Bohman, Benjamin; Nyberg, Gisela; Schäfer Elinder, Liselotte

2018-01-01

Background: According to social cognitive theory, self-efficacy is central to behavior change. Consequently, parental self-efficacy (PSE) for influencing children's dietary, physical activity (PA), sedentary, and screen time behaviors is important for child obesity prevention. The aim of this study was to evaluate the psychometric properties of an…

Effects of "Like Type" Sex Pairings between Applicants-Principals and Type of Focal Position Considered at the Screening Stage of the Selection Process

ERIC Educational Resources Information Center

Young, I. Phillip

2005-01-01

This study addresses the screening decisions for a national random sample of high school principals as viewed from the attraction-similarity theory of interpersonal perceptions. Independent variables are the sex of principals, sex of applicants, and the type of focal positions sought by hypothetical job applicants (teacher or counselor). Dependent…

Preventive Care in Appalachia: Use of the Theory of Planned Behavior to Identify Barriers to Participation in Cholesterol Screenings among West Virginians

ERIC Educational Resources Information Center

Deskins, Shelli; Harris, Carole V.; Bradlyn, Andrew S.; Cottrell, Lesley; Coffman, Jessica W.; Olexa, Julie; Neal, William

2006-01-01

Context: West Virginians are at increased risk for heart disease. Given that the process of atherosclerosis begins in childhood, the Coronary Artery Risk Detection in Appalachian Communities Project was developed to reduce this risk by implementing a cholesterol screening program in the schools. However, participation rates have been less than…

Current maternal age recommendations for prenatal diagnosis: a reappraisal using the expected utility theory.

PubMed

Sicherman, N; Bombard, A T; Rappoport, P

1995-01-01

The expected utility theory suggests eliminating an age-specific criterion for recommending prenatal diagnosis to patients. We isolate the factors which patients and physicians need to consider intelligently in prenatal diagnosis, and show that the sole use of a threshold age as a screening device is inadequate. Such a threshold fails to consider adequately patients' attitudes regarding many of the possible outcomes of prenatal diagnosis; in particular, the birth of a chromosomally abnormal child and procedural-related miscarriages. It also precludes testing younger women and encourages testing in patients who do not necessarily require or desire it. All pregnant women should be informed about their prenatal diagnosis options, screening techniques, and diagnostic procedures, including their respective limitations, risks, and benefits.

Astrophysical tests of modified gravity: Constraints from distance indicators in the nearby universe

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

Jain, Bhuvnesh; Vikram, Vinu; Sakstein, Jeremy

2013-12-10

We use distance measurements in the nearby universe to carry out new tests of gravity, surpassing other astrophysical tests by over two orders of magnitude for chameleon theories. The three nearby distance indicators—cepheids, tip of the red giant branch (TRGB) stars, and water masers—operate in gravitational fields of widely different strengths. This enables tests of scalar-tensor gravity theories because they are screened from enhanced forces to different extents. Inferred distances from cepheids and TRGB stars are altered (in opposite directions) over a range of chameleon gravity theory parameters well below the sensitivity of cosmological probes. Using published data, we havemore » compared cepheid and TRGB distances in a sample of unscreened dwarf galaxies within 10 Mpc. We use a comparable set of screened galaxies as a control sample. We find no evidence for the order unity force enhancements expected in these theories. Using a two-parameter description of the models (the coupling strength and background field value), we obtain constraints on both the chameleon and symmetron screening scenarios. In particular we show that f(R) models with background field values f {sub R0} above 5 × 10{sup –7} are ruled out at the 95% confidence level. We also compare TRGB and maser distances to the galaxy NGC 4258 as a second test for larger field values. While there are several approximations and caveats in our study, our analysis demonstrates the power of gravity tests in the local universe. We discuss the prospects for additional improved tests with future observations.« less

Conceptualisation of patient satisfaction: a systematic narrative literature review.

PubMed

Batbaatar, Enkhjargal; Dorjdagva, Javkhlanbayar; Luvsannyam, Ariunbat; Amenta, Pietro

2015-09-01

Patient satisfaction concept is widely measured due to its appropriateness to health service; however, evidence suggests that it is a poorly developed concept. This article is a first part of a two-part series of research with a goal to review a current conceptual framework of patient satisfaction and to bring the concept for further operationalisation procedures. The current article aimed to review a theoretical framework that helps the next article to review determinants of patient satisfaction for designing a measurement system. The study used a systematic review method, meta-narrative review, based on the RAMESES guideline with the phases of screening evidence, appraisal evidence, data extraction and synthesis. Patient satisfaction theoretical articles were searched on the two databases MEDLINE and CINAHL. Inclusion criteria were articles published between 1980 and 2014, and English language papers only. There were 36 articles selected for the synthesis. Results showed that most of the patient satisfaction theories and formulations are based on marketing theories and defined as how well health service fulfils patient expectations. However, review demonstrated that a relationship between expectation and satisfaction is unclear and the concept expectation itself is not distinctly theorised as well. Researchers brought satisfaction theories from other fields to the current healthcare literature without much adaptation. Thus, there is a need to attempt to define the patient satisfaction concept from other perspectives or to learn how patients evaluate the care rather than struggling to describe it by consumerist theories. © Royal Society for Public Health 2015.

Local food environment interventions to improve healthy food choice in adults: a systematic review and realist synthesis protocol.

PubMed

Penney, Tarra L; Brown, Helen Elizabeth; Maguire, Eva R; Kuhn, Isla; Monsivais, Pablo

2015-05-03

Local food environments have been linked with dietary intake and obesity in adults. However, overall evidence remains mixed with calls for increased theoretical and conceptual clarity related to how availability of neighbourhood food outlets, and within-outlet food options, influence food purchasing and consumption. The purpose of this work is to develop a programme theory of food availability, supported by empirical evidence from a range of local food environment interventions. A systematic search of the literature will be followed by duplicate screening and quality assessment (using the Effective Public Health Practice Project tool). Realist synthesis will then be conducted according to the Realist And Meta-narrative Evidence Syntheses: Evolving Standards (RAMESES) publication standards, including transparent appraisal, synthesis and drawing conclusions via consensus. The final synthesis will propose an evidence-based programme theory of food availability, including evidence mapping to demonstrate contextual factors, pathways of influence and potential mechanisms. With the paucity of empirically supported programme theories used in current local food environment interventions to improve food availability, this synthesis may be used to understand how and why interventions work, and thus inform the development of theory-driven, evidence-based interventions to improve healthy food choice and future empirical work. PROSPERO CRD42014009808. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

Quiver W-algebras

NASA Astrophysics Data System (ADS)

Kimura, Taro; Pestun, Vasily

2018-06-01

For a quiver with weighted arrows, we define gauge-theory K-theoretic W-algebra generalizing the definition of Shiraishi et al. and Frenkel and Reshetikhin. In particular, we show that the qq-character construction of gauge theory presented by Nekrasov is isomorphic to the definition of the W-algebra in the operator formalism as a commutant of screening charges in the free field representation. Besides, we allow arbitrary quiver and expect interesting applications to representation theory of generalized Borcherds-Kac-Moody Lie algebras, their quantum affinizations and associated W-algebras.

A molecular Debye-Huckel theory of solvation in polar fluids: An extension of the Born model

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

Xiao, Tiejun; Song, Xueyu

A dielectric response theory of solvation beyond the conventional Born model for polar fluids is presented. The dielectric response of a polar fluid is described by a Born response mode and a linear combination of Debye-Hückel-like response modes that capture the nonlocal response of polar fluids. The Born mode is characterized by a bulk dielectric constant, while a Debye-Hückel mode is characterized by its corresponding Debye screening length. Both the bulk dielectric constant and the Debye screening lengths are determined from the bulk dielectric function of the polar fluid. The linear combination coefficients of the response modes are evaluated inmore » a self-consistent way and can be used to evaluate the electrostatic contribution to the thermodynamic properties of a polar fluid. In conclusion, our theory is applied to a dipolar hard sphere fluid as well as interaction site models of polar fluids such as water, where the electrostatic contribution to their thermodynamic properties can be obtained accurately.« less

A molecular Debye-Huckel theory of solvation in polar fluids: An extension of the Born model

DOE PAGES

Xiao, Tiejun; Song, Xueyu

2017-12-06

A dielectric response theory of solvation beyond the conventional Born model for polar fluids is presented. The dielectric response of a polar fluid is described by a Born response mode and a linear combination of Debye-Hückel-like response modes that capture the nonlocal response of polar fluids. The Born mode is characterized by a bulk dielectric constant, while a Debye-Hückel mode is characterized by its corresponding Debye screening length. Both the bulk dielectric constant and the Debye screening lengths are determined from the bulk dielectric function of the polar fluid. The linear combination coefficients of the response modes are evaluated inmore » a self-consistent way and can be used to evaluate the electrostatic contribution to the thermodynamic properties of a polar fluid. In conclusion, our theory is applied to a dipolar hard sphere fluid as well as interaction site models of polar fluids such as water, where the electrostatic contribution to their thermodynamic properties can be obtained accurately.« less

A molecular Debye-Hückel theory of solvation in polar fluids: An extension of the Born model

NASA Astrophysics Data System (ADS)

Xiao, Tiejun; Song, Xueyu

2017-12-01

A dielectric response theory of solvation beyond the conventional Born model for polar fluids is presented. The dielectric response of a polar fluid is described by a Born response mode and a linear combination of Debye-Hückel-like response modes that capture the nonlocal response of polar fluids. The Born mode is characterized by a bulk dielectric constant, while a Debye-Hückel mode is characterized by its corresponding Debye screening length. Both the bulk dielectric constant and the Debye screening lengths are determined from the bulk dielectric function of the polar fluid. The linear combination coefficients of the response modes are evaluated in a self-consistent way and can be used to evaluate the electrostatic contribution to the thermodynamic properties of a polar fluid. Our theory is applied to a dipolar hard sphere fluid as well as interaction site models of polar fluids such as water, where the electrostatic contribution to their thermodynamic properties can be obtained accurately.

A molecular Debye-Hückel theory of solvation in polar fluids: An extension of the Born model.

PubMed

Xiao, Tiejun; Song, Xueyu

2017-12-07

A dielectric response theory of solvation beyond the conventional Born model for polar fluids is presented. The dielectric response of a polar fluid is described by a Born response mode and a linear combination of Debye-Hückel-like response modes that capture the nonlocal response of polar fluids. The Born mode is characterized by a bulk dielectric constant, while a Debye-Hückel mode is characterized by its corresponding Debye screening length. Both the bulk dielectric constant and the Debye screening lengths are determined from the bulk dielectric function of the polar fluid. The linear combination coefficients of the response modes are evaluated in a self-consistent way and can be used to evaluate the electrostatic contribution to the thermodynamic properties of a polar fluid. Our theory is applied to a dipolar hard sphere fluid as well as interaction site models of polar fluids such as water, where the electrostatic contribution to their thermodynamic properties can be obtained accurately.

A prediction model for cognitive performance in health ageing using diffusion tensor imaging with graph theory.

PubMed

Yun, Ruijuan; Lin, Chung-Chih; Wu, Shuicai; Huang, Chu-Chung; Lin, Ching-Po; Chao, Yi-Ping

2013-01-01

In this study, we employed diffusion tensor imaging (DTI) to construct brain structural network and then derive the connection matrices from 96 healthy elderly subjects. The correlation analysis between these topological properties of network based on graph theory and the Cognitive Abilities Screening Instrument (CASI) index were processed to extract the significant network characteristics. These characteristics were then integrated to estimate the models by various machine-learning algorithms to predict user's cognitive performance. From the results, linear regression model and Gaussian processes model showed presented better abilities with lower mean absolute errors of 5.8120 and 6.25 to predict the cognitive performance respectively. Moreover, these extracted topological properties of brain structural network derived from DTI also could be regarded as the bio-signatures for further evaluation of brain degeneration in healthy aged and early diagnosis of mild cognitive impairment (MCI).

Computational predictions of energy materials using density functional theory

NASA Astrophysics Data System (ADS)

Jain, Anubhav; Shin, Yongwoo; Persson, Kristin A.

2016-01-01

In the search for new functional materials, quantum mechanics is an exciting starting point. The fundamental laws that govern the behaviour of electrons have the possibility, at the other end of the scale, to predict the performance of a material for a targeted application. In some cases, this is achievable using density functional theory (DFT). In this Review, we highlight DFT studies predicting energy-related materials that were subsequently confirmed experimentally. The attributes and limitations of DFT for the computational design of materials for lithium-ion batteries, hydrogen production and storage materials, superconductors, photovoltaics and thermoelectric materials are discussed. In the future, we expect that the accuracy of DFT-based methods will continue to improve and that growth in computing power will enable millions of materials to be virtually screened for specific applications. Thus, these examples represent a first glimpse of what may become a routine and integral step in materials discovery.

Miscibility phase diagram of ring-polymer blends: A topological effect.

PubMed

Sakaue, Takahiro; Nakajima, Chihiro H

2016-04-01

The miscibility of polymer blends, a classical problem in polymer science, may be altered, if one or both of the component do not have chain ends. Based on the idea of topological volume, we propose a mean-field theory to clarify how the topological constraints in ring polymers affect the phase behavior of the blends. While the large enhancement of the miscibility is expected for ring-linear polymer blends, the opposite trend toward demixing, albeit comparatively weak, is predicted for ring-ring polymer blends. Scaling formulas for the shift of critical point for both cases are derived. We discuss the valid range of the present theory, and the crossover to the linear polymer blends behaviors, which is expected for short chains. These analyses put forward a view that the topological constraints could be represented as an effective excluded-volume effects, in which the topological length plays a role of the screening factor.

General Second-Order Scalar-Tensor Theory and Self-Tuning

NASA Astrophysics Data System (ADS)

Charmousis, Christos; Copeland, Edmund J.; Padilla, Antonio; Saffin, Paul M.

2012-02-01

Starting from the most general scalar-tensor theory with second-order field equations in four dimensions, we establish the unique action that will allow for the existence of a consistent self-tuning mechanism on Friedmann-Lemaître-Robertson-Walker backgrounds, and show how it can be understood as a combination of just four base Lagrangians with an intriguing geometric structure dependent on the Ricci scalar, the Einstein tensor, the double dual of the Riemann tensor, and the Gauss-Bonnet combination. Spacetime curvature can be screened from the net cosmological constant at any given moment because we allow the scalar field to break Poincaré invariance on the self-tuning vacua, thereby evading the Weinberg no-go theorem. We show how the four arbitrary functions of the scalar field combine in an elegant way opening up the possibility of obtaining nontrivial cosmological solutions.

The Effect of Personal Characteristics, Perceived Threat, Efficacy and Breast Cancer Anxiety on Breast Cancer Screening Activation

PubMed Central

De Pelsmacker, Patrick; Lewi, Martine; Cauberghe, Veroline

2017-01-01

In order to activate women to participate in breast cancer screening programs, a good understanding is needed of the personal characteristics that influence how women can be activated to search for more information, consult friends and doctors, and participate in breast cancer screening programs. In the current study, we investigate the effect of six personal characteristics that have in previous research been identified as important triggers of health behavior on breast cancer screening activation: Health awareness, Need for Cognition, Affect Intensity, Breast cancer knowledge, Topic involvement, and the Perceived breast cancer risk. We test the effect of these factors on four activation variables: intention of future information seeking, forwarding the message to a friend, talking to a doctor, and actual breast cancer screening attendance. Additionally, we try to unravel the process by means of which the antecedents (the six personal characteristics) lead to activation. To that end, we test the mediating role of perceived breast cancer threat, perceived efficacy of screening, and the evoked breast cancer anxiety as mediators in this process. The data were collected by means of a cross-sectional survey in a sample of 700 Flemish (Belgium) women who were invited to the free-of-charge breast cancer population screening. Screening attendance of this sample was provided by the government agency in charge of the organisation of the screening. Health awareness, affects intensity, topic involvement, and perceived risk have the strongest influence on activation. Breast cancer anxiety and perceived breast cancer threat have a substantial mediation effect on these effects. Efficacy perceptions are less important in the activation process. Increased health awareness and a higher level of perceived risk lead to less participation in the free of charge population based breast screening program. Implications for theory and practice are offered. The limitation of the study is that only a standard invitation message was used. In future research, other types of awareness and activation messages should be tested. Additionally, the analysis could be refined by investigating the potentially different activation process in different subgroups of women. PMID:28953261

Direct measurement of sub-Debye-length attraction between oppositely charged surfaces.

PubMed

Kampf, Nir; Ben-Yaakov, Dan; Andelman, David; Safran, S A; Klein, Jacob

2009-09-11

Using a surface force balance with fast video analysis, we have measured directly the attractive forces between oppositely charged solid surfaces (charge densities sigma(+), sigma(-)) across water over the entire range of interaction, in particular, at surface separations D below the Debye screening length lambda(S). At very low salt concentration we find a long-ranged attraction between the surfaces (onset ca. 100 nm), whose variation at D

Thermodynamics of rough colloidal surfaces

NASA Astrophysics Data System (ADS)

Goldstein, Raymond E.; Halsey, Thomas C.; Leibig, Michael

1991-03-01

In Debye-Hückel theory, the free energy of an electric double layer near a colloidal (or any other) surface can be related to the statistics of random walks near that surface. We present a numerical method based on this correspondence for the calculation of the double-layer free energy for an arbitrary charged or conducting surface. For self-similar surfaces, we propose a scaling law for the behavior of the free energy as a function of the screening length and the surface dimension. This scaling law is verified by numerical computation. Capacitance measurements on rough surfaces of, e.g., colloids can test these predictions.

Dynamic Training Elements in a Circuit Theory Course to Implement a Self-Directed Learning Process

ERIC Educational Resources Information Center

Krouk, B. I.; Zhuravleva, O. B.

2009-01-01

This paper reports on the implementation of a self-directed learning process in a circuit theory course, incorporating dynamic training elements which were designed on the basis of a cybernetic model of cognitive process management. These elements are centrally linked in a dynamic learning frame, created on the monitor screen, which displays the…

Applying Item Response Theory to the Development of a Screening Adaptation of the Goldman-Fristoe Test of Articulation-Second Edition

ERIC Educational Resources Information Center

Brackenbury, Tim; Zickar, Michael J.; Munson, Benjamin; Storkel, Holly L.

2017-01-01

Purpose: Item response theory (IRT) is a psychometric approach to measurement that uses latent trait abilities (e.g., speech sound production skills) to model performance on individual items that vary by difficulty and discrimination. An IRT analysis was applied to preschoolers' productions of the words on the Goldman-Fristoe Test of…

Partnership for Healthier Asians: Disseminating Evidence-Based Practices in Asian-American Communities Using a Market-Oriented and Multilevel Approach

PubMed Central

Kim, Karen; Quinn, Michael; Chandrasekar, Edwin; Patel, Reena

2016-01-01

Background One of the greatest challenges facing health promotion and disease prevention is translating research findings into evidence-based practices (EBP). There is currently a limited research base to inform the design of dissemination action plans, especially within medically underserved communities. Objective The objective of this paper is to describe an innovative study protocol to disseminate colorectal cancer (CRC) screening guidelines in seven Asian subgroups. Methods This study integrated a market-oriented Push-Pull-Infrastructure Model, Diffusion of Innovation Theory, and community-based participatory research approach to create a community-centered dissemination framework. Consumer research, through focus groups and community-wide surveys, was centered on the adopters to ensure a multilevel intervention was well designed and effective. Results Collaboration took place between an academic institution and eight community-based organizations. These groups worked together to conduct thorough consumer research. A sample of 72 Asian Americans participated in 8 focus groups, and differences were noted across ethnic groups. Furthermore, 464 community members participated in an Individual Client Survey. Most participants agreed that early detection of cancer was important (434/464, 93.5%), cancer could happen to anyone (403/464, 86.9%), CRC could be prevented (344/464, 74.1%), and everyone should screen for CRC (389/464, 83.8%). However, 35.8% (166/464) of participants also felt that people were better off not knowing it they had cancer, and 45.5% (211/464) would screen only when they had symptoms. Most participants indicated that they would screen upon their doctor’s recommendation, but half reported that they only saw a doctor when they were sick. Data collection currently is underway for a multilevel intervention (community health advisor and social marketing campaign) and will conclude March 2016. We expect that analysis and results will be available by June 2016. Conclusions This study outlines a complementary role for researchers and community organizations in disseminating EBP, and incorporates social interactions and influences to move individuals from simple awareness to decisions towards positive action. PMID:27312079

Mediation of the Physical Activity and Healthy Nutrition Behaviors of Preschool Children by Maternal Cognition in China.

PubMed

Xu, Xianglong; Sharma, Manoj; Liu, Lingli; Hu, Ping; Zhao, Yong

2016-09-13

(1) OBJECTIVE: We aimed to explore the role of social cognitive theory (SCT) of mothers in the physical activity and healthy nutrition behaviors of preschool children; (2) METHODS: We used a self-administered five-point Likert common physical activity and nutrition behaviors scale in Chinese based on a social cognitive theory scale in English with established validity and reliability in the USA. The current study adopted the proportional sampling method to survey mothers of preschool children in four areas-namely, Chongqing, Chengdu, Taiyuan, and Shijiazhuang-of China; (3) RESULTS: We included 1208 mothers (80.0% mothers of normal weight children, age 31.87 ± 4.19 years). Positive correlations were found between maternal social cognition and preschool children's physical activity (PA) behavior (p < 0.0001). However, an insignificant correlation is observed between preschool children's fruits and vegetables (FV) behavior, screen time (ST) behavior, and maternal social cognition; (4) CONCLUSIONS: This study provides some implications for increasing fruit and vegetable consumption, increasing physical activity time, and reducing screen time in preschool children using SCT in China. Maternal social cognition is associated with preschool children's PA behavior, and the results suggest that maternal social cognition may not affect children FV and ST behaviors. Further research is necessary to test the mediation of maternal social cognition on preschool children's ST behavior and the correlations between maternal social cognition and children's ST behavior.

Nonlinear Plasma Response to Resonant Magnetic Perturbation in Rutherford Regime

NASA Astrophysics Data System (ADS)

Zhu, Ping; Yan, Xingting; Huang, Wenlong

2017-10-01

Recently a common analytic relation for both the locked mode and the nonlinear plasma response in the Rutherford regime has been developed based on the steady-state solution to the coupled dynamic system of magnetic island evolution and torque balance equations. The analytic relation predicts the threshold and the island size for the full penetration of resonant magnetic perturbation (RMP). It also rigorously proves a screening effect of the equilibrium toroidal flow. In this work, we test the theory by solving for the nonlinear plasma response to a single-helicity RMP of a circular-shaped limiter tokamak equilibrium with a constant toroidal flow, using the initial-value, full MHD simulation code NIMROD. Time evolution of the parallel flow or ``slip frequency'' profile and its asymptotic approach to steady state obtained from the NIMROD simulations qualitatively agree with the theory predictions. Further comparisons are carried out for the saturated island size, the threshold for full mode penetration, as well as the screening effects of equilibrium toroidal flow in order to understand the physics of nonlinear plasma response in the Rutherford regime. Supported by National Magnetic Confinement Fusion Science Program of China Grants 2014GB124002 and 2015GB101004, the 100 Talent Program of the Chinese Academy of Sciences, and U.S. Department of Energy Grants DE-FG02-86ER53218 and DE-FC02-08ER54975.

Non-equilibrium Transport in Carbon based Adsorbate Systems

NASA Astrophysics Data System (ADS)

Fürst, Joachim; Brandbyge, Mads; Stokbro, Kurt; Jauho, Antti-Pekka

2007-03-01

We have used the Atomistix Tool Kit(ATK) and TranSIESTA[1] packages to investigate adsorption of iron atoms on a graphene sheet. The technique of both codes is based on density functional theory using local basis sets[2], and non-equilibrium Green's functions (NEGF) to calculate the charge distribution under external bias. Spin dependent electronic structure calculations are performed for different iron coverages. These reveal adsorption site dependent charge transfer from iron to graphene leading to screening effects. Transport calculations show spin dependent scattering of the transmission which is analysed obtaining the transmission eigenchannels for each spin type. The phenomena of electromigration of iron in these systems at finite bias will be discussed, estimating the so-called wind force from the reflection[3]. [1] M. Brandbyge, J.-L. Mozos, P. Ordejon, J. Taylor, and K. Stokbro. Physical Review B (Condensed Matter and Materials Physics), 65(16):165401/11-7, 2002. [2] Jose M. Soler, Emilio Artacho, Julian D. Gale, Alberto Garcia, Javier Junquera, Pablo Ordejon, and Daniel Sanchez-Portal. Journal of Physics Condensed Matter, 14(11):2745-2779, 2002. [3] Sorbello. Theory of electromigration. Solid State Physics, 1997.

Early detection of Alzheimer disease: methods, markers, and misgivings.

PubMed

Green, R C; Clarke, V C; Thompson, N J; Woodard, J L; Letz, R

1997-01-01

There is at present no reliable predictive test for most forms of Alzheimer disease (AD). Although some information about future risk for disease is available in theory through ApoE genotyping, it is of limited accuracy and utility. Once neuroprotective treatments are available for AD, reliable early detection will become a key component of the treatment strategy. We recently conducted a pilot survey eliciting attitudes and beliefs toward an unspecified and hypothetical predictive test for AD. The survey was completed by a convenience sample of 176 individuals, aged 22-77, which was 75% female, 30% African-American, and of which 33% had a family member with AD. The survey revealed that 69% of this sample would elect to obtain predictive testing for AD if the test were 100% accurate. Individuals were more likely to desire predictive testing if they had an a priori belief that they would develop AD (p = 0.0001), had a lower educational level (p = 0.003), were worried that they would develop AD (p = 0.02), had a self-defined history of depression (p = 0.04), and had a family member with AD (p = 0.04). However, the desire for predictive testing was not significantly associated with age, gender, ethnicity, or income. The desire to obtain predictive testing for AD decreased as the assumed accuracy of the hypothetical test decreased. A better short-term strategy for early detection of AD may be computer-based neuropsychological screening of at-risk (older aged) individuals to identify very early cognitive impairment. Individuals identified in this manner could be referred for diagnostic evaluation and early cases of AD could be identified and treated. A new self-administered, touch-screen, computer-based, neuropsychological screening instrument called Neurobehavioral Evaluation System-3 is described, which may facilitate this type of screening.

Barriers to and factors facilitating breast cancer screening among Iranian women: a qualitative study.

PubMed

Lamyian, M; Hydarnia, A; Ahmadi, F; Faghihzadeh, S; Aguilar-Vafaie, M E

2007-01-01

This study used qualitative methodology to understand Iranian women's views about barriers to and factors facilitating screening for early detection of breast cancer. Using grounded theory with in-depth interviews of 31 participants, themes emerged from the data in 2 main categories (internal and external) with 3 sub-categories: women's attitudes, feelings and beliefs; women's social network experiences; and accessibility. Facilitating factors for screening were self-care, fear, proactive coping, state of mind and advocacy. Barriers were negligence, cancer-related fear, low self-efficacy, fatalism, misinformation, ineffective health communication and competing priorities.

The electron screening puzzle and nuclear clustering

DOE PAGES

Spitaleri, C.; Bertulani, C. A.; Fortunato, L.; ...

2016-02-12

Accurate measurements of nuclear reactions of astrophysical interest within, or close to, the Gamow peak show evidence of an unexpected effect attributed to the presence of atomic electrons in the target. The experiments need to include an effective "screening" potential to explain the enhancement of the cross sections at the lowest measurable energies. Despite various theoretical studies conducted over the past 20 years and numerous experimental measurements, a theory has not yet been found that can explain the cause of the exceedingly high values of the screening potential needed to explain the data. Furthermore, in this letter we show thatmore » instead of an atomic physics solution of the "electron screening puzzle", the reason for the large screening potential values is in fact due to clusterization effects in nuclear reactions, in particular for reaction involving light nuclei.« less

Aging, Emotion, Attention, and Binding in the Taboo Stroop Task: Data and Theories.

PubMed

MacKay, Donald G; Johnson, Laura W; Graham, Elizabeth R; Burke, Deborah M

2015-10-14

How does aging impact relations between emotion, memory, and attention? To address this question, young and older adults named the font colors of taboo and neutral words, some of which recurred in the same font color or screen location throughout two color-naming experiments. The results indicated longer color-naming response times (RTs) for taboo than neutral base-words (taboo Stroop interference); better incidental recognition of colors and locations consistently associated with taboo versus neutral words (taboo context-memory enhancement); and greater speed-up in color-naming RTs with repetition of color-consistent than color-inconsistent taboo words, but no analogous speed-up with repetition of location-consistent or location-inconsistent taboo words (the consistency type by repetition interaction for taboo words). All three phenomena remained constant with aging, consistent with the transmission deficit hypothesis and binding theory, where familiar emotional words trigger age-invariant reactions for prioritizing the binding of contextual features to the source of emotion. Binding theory also accurately predicted the interaction between consistency type and repetition for taboo words. However, one or more aspects of these phenomena failed to support the inhibition deficit hypothesis, resource capacity theory, or socio-emotional selectivity theory. We conclude that binding theory warrants further test in a range of paradigms, and that relations between aging and emotion, memory, and attention may depend on whether the task and stimuli trigger fast-reaction, involuntary binding processes, as in the taboo Stroop paradigm.

Aging, Emotion, Attention, and Binding in the Taboo Stroop Task: Data and Theories

PubMed Central

MacKay, Donald G.; Johnson, Laura W.; Graham, Elizabeth R.; Burke, Deborah M.

2015-01-01

How does aging impact relations between emotion, memory, and attention? To address this question, young and older adults named the font colors of taboo and neutral words, some of which recurred in the same font color or screen location throughout two color-naming experiments. The results indicated longer color-naming response times (RTs) for taboo than neutral base-words (taboo Stroop interference); better incidental recognition of colors and locations consistently associated with taboo versus neutral words (taboo context-memory enhancement); and greater speed-up in color-naming RTs with repetition of color-consistent than color-inconsistent taboo words, but no analogous speed-up with repetition of location-consistent or location-inconsistent taboo words (the consistency type by repetition interaction for taboo words). All three phenomena remained constant with aging, consistent with the transmission deficit hypothesis and binding theory, where familiar emotional words trigger age-invariant reactions for prioritizing the binding of contextual features to the source of emotion. Binding theory also accurately predicted the interaction between consistency type and repetition for taboo words. However, one or more aspects of these phenomena failed to support the inhibition deficit hypothesis, resource capacity theory, or socio-emotional selectivity theory. We conclude that binding theory warrants further test in a range of paradigms, and that relations between aging and emotion, memory, and attention may depend on whether the task and stimuli trigger fast-reaction, involuntary binding processes, as in the taboo Stroop paradigm. PMID:26473909

Autosophy information theory provides lossless data and video compression based on the data content

NASA Astrophysics Data System (ADS)

Holtz, Klaus E.; Holtz, Eric S.; Holtz, Diana

1996-09-01

A new autosophy information theory provides an alternative to the classical Shannon information theory. Using the new theory in communication networks provides both a high degree of lossless compression and virtually unbreakable encryption codes for network security. The bandwidth in a conventional Shannon communication is determined only by the data volume and the hardware parameters, such as image size; resolution; or frame rates in television. The data content, or what is shown on the screen, is irrelevant. In contrast, the bandwidth in autosophy communication is determined only by data content, such as novelty and movement in television images. It is the data volume and hardware parameters that become irrelevant. Basically, the new communication methods use prior 'knowledge' of the data, stored in a library, to encode subsequent transmissions. The more 'knowledge' stored in the libraries, the higher the potential compression ratio. 'Information' is redefined as that which is not already known by the receiver. Everything already known is redundant and need not be re-transmitted. In a perfect communication each transmission code, called a 'tip,' creates a new 'engram' of knowledge in the library in which each tip transmission can represent any amount of data. Autosophy theories provide six separate learning modes, or omni dimensional networks, all of which can be used for data compression. The new information theory reveals the theoretical flaws of other data compression methods, including: the Huffman; Ziv Lempel; LZW codes and commercial compression codes such as V.42bis and MPEG-2.

Near-edge band structures and band gaps of Cu-based semiconductors predicted by the modified Becke-Johnson potential plus an on-site Coulomb U

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

Zhang, Yubo; Zhang, Jiawei; Wang, Youwei

Diamond-like Cu-based multinary semiconductors are a rich family of materials that hold promise in a wide range of applications. Unfortunately, accurate theoretical understanding of the electronic properties of these materials is hindered by the involvement of Cu d electrons. Density functional theory (DFT) based calculations using the local density approximation or generalized gradient approximation often give qualitative wrong electronic properties of these materials, especially for narrow-gap systems. The modified Becke-Johnson (mBJ) method has been shown to be a promising alternative to more elaborate theory such as the GW approximation for fast materials screening and predictions. However, straightforward applications of themore » mBJ method to these materials still encounter significant difficulties because of the insufficient treatment of the localized d electrons. We show that combining the promise of mBJ potential and the spirit of the well-established DFT + U method leads to a much improved description of the electronic structures, including the most challenging narrow-gap systems. A survey of the band gaps of about 20 Cu-based semiconductors calculated using the mBJ + U method shows that the results agree with reliable values to within ±0.2 eV.« less

Synthesis, characterization, antimicrobial screening and computational studies of 4-[3-(4-methoxy-phenyl)-allylideneamino]-1,5-dimethyl-2-phenyl-1,2-dihydro-pyrazol-3-one

NASA Astrophysics Data System (ADS)

Obasi, L. N.; Kaior, G. U.; Rhyman, L.; Alswaidan, Ibrahim A.; Fun, Hoong-Kun; Ramasami, P.

2016-09-01

The Schiff base, 4-[3-(4-methoxy-phenyl)-allylideneamino]-1,5-dimethyl-2-phenyl-1,2-dihydro-pyrazol-3-one (TPMC/AAP) was synthesized by the condensation of 4-aminoantipyrine (4-amino-1,5-dimethyl-2-phenylpyrazole-3-one) and trans-para-methoxycinnamaldehyde (trans-3,4-methoxyphenyl-2-propenal) in dry methanol at 75 °C. The compound was characterized using elemental microanalysis, IR, NMR, UV spectroscopies and single-crystal X-ray crystallography. The X-ray structure determination shows that the Schiff base, (TPMC/AAP) is orthorhombic with the Pbca space group. The anti-microbial screening of the compound was carried out with Escherichia coli, Bacillus subtillis, Staphylococcus aureus, Pseudemonas aeruginosa, Candida albicans and Aspergillus niger using agar well diffusion method. The Schiff base possesses significant antimicrobial activity. The minimum inhibitory concentration (MIC) of the compound was also determined and the activity was compared with that of conventional drugs ciprofloxacin and ketoconazole. The compound (TPMC/AAP) showed varying activity against the cultured bacteria and fungi used. To complement the experimental data, density functional theory (DFT) was used to have deeper understanding into the molecular parameters and infrared spectra of the compound.

Dynamical effects in x-ray absorption spectra of graphene and monolayered h -BN on Ni(111)

NASA Astrophysics Data System (ADS)

Rusz, J.; Preobrajenski, A. B.; Ng, May Ling; Vinogradov, N. A.; Mårtensson, N.; Wessely, O.; Sanyal, B.; Eriksson, O.

2010-02-01

We present first-principles calculations of x-ray absorption spectra of graphene and hexagonal BN monolayer on the Ni(111) substrate. Including dynamical core-hole screening effects according to the theory of Mahan-Nozières-de Dominics (MND) results in an overall good agreement with previously published experimental data and our new observations. This approach provides a unified first-principles description of the electronic structure and core excitations in the sp2 -bonded materials on metal surfaces and a better insight into the dynamics of screening effects. We demonstrate in particular that the observed spectral features of graphene and hexagonal BN can be well reproduced with the MND theory, and that they are determined by a delicate balance between initial and final-state effects.

STELLAR STRUCTURE AND TESTS OF MODIFIED GRAVITY

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

Chang, Philip; Hui, Lam, E-mail: pchang@cita.utoronto.ca, E-mail: lhui@astro.columbia.edu

2011-05-01

Theories that attempt to explain cosmic acceleration by modifying gravity typically introduces a long-range scalar force that needs to be screened on small scales. One common screening mechanism is the chameleon, where the scalar force is screened in environments with a sufficiently deep gravitational potential, but acts unimpeded in regions with a shallow gravitational potential. This leads to a variation in the overall gravitational G with environment. We show that such a variation can occur within a star itself, significantly affecting its evolution and structure, provided that the host galaxy is unscreened. The effect is most pronounced for red giants,more » which would be smaller by a factor of tens of percent and thus hotter by hundreds of Kelvin, depending on the parameters of the underlying scalar-tensor theory. Careful measurements of these stars in suitable environments (nearby dwarf galaxies not associated with groups or clusters) would provide constraints on the chameleon mechanism that are four orders of magnitude better than current large-scale structure limits and two orders of magnitude better than present solar system tests.« less

Dynamical screening of the van der Waals interaction between graphene layers.

PubMed

Dappe, Y J; Bolcatto, P G; Ortega, J; Flores, F

2012-10-24

The interaction between graphene layers is analyzed combining local orbital DFT and second order perturbation theory. For this purpose we use the linear combination of atomic orbitals-orbital occupancy (LCAO-OO) formalism, that allows us to separate the interaction energy as the sum of a weak chemical interaction between graphene layers plus the van der Waals interaction (Dappe et al 2006 Phys. Rev. B 74 205434). In this work, the weak chemical interaction is calculated by means of corrected-LDA calculations using an atomic-like sp(3)d(5) basis set. The van der Waals interaction is calculated by means of second order perturbation theory using an atom-atom interaction approximation and the atomic-like-orbital occupancies. We also analyze the effect of dynamical screening in the van der Waals interaction using a simple model. We find that this dynamical screening reduces by 40% the van der Waals interaction. Taking this effect into account, we obtain a graphene-graphene interaction energy of 70 ± 5 meV/atom in reasonable agreement with the experimental evidence.

Metaheuristics-Assisted Combinatorial Screening of Eu2+-Doped Ca-Sr-Ba-Li-Mg-Al-Si-Ge-N Compositional Space in Search of a Narrow-Band Green Emitting Phosphor and Density Functional Theory Calculations.

PubMed

Lee, Jin-Woong; Singh, Satendra Pal; Kim, Minseuk; Hong, Sung Un; Park, Woon Bae; Sohn, Kee-Sun

2017-08-21

A metaheuristics-based design would be of great help in relieving the enormous experimental burdens faced during the combinatorial screening of a huge, multidimensional search space, while providing the same effect as total enumeration. In order to tackle the high-throughput powder processing complications and to secure practical phosphors, metaheuristics, an elitism-reinforced nondominated sorting genetic algorithm (NSGA-II), was employed in this study. The NSGA-II iteration targeted two objective functions. The first was to search for a higher emission efficacy. The second was to search for narrow-band green color emissions. The NSGA-II iteration finally converged on BaLi 2 Al 2 Si 2 N 6 :Eu 2+ phosphors in the Eu 2+ -doped Ca-Sr-Ba-Li-Mg-Al-Si-Ge-N compositional search space. The BaLi 2 Al 2 Si 2 N 6 :Eu 2+ phosphor, which was synthesized with no human intervention via the assistance of NSGA-II, was a clear single phase and gave an acceptable luminescence. The BaLi 2 Al 2 Si 2 N 6 :Eu 2+ phosphor as well as all other phosphors that appeared during the NSGA-II iterations were examined in detail by employing powder X-ray diffraction-based Rietveld refinement, X-ray absorption near edge structure, density functional theory calculation, and time-resolved photoluminescence. The thermodynamic stability and the band structure plausibility were confirmed, and more importantly a novel approach to the energy transfer analysis was also introduced for BaLi 2 Al 2 Si 2 N 6 :Eu 2+ phosphors.

Systematic Review and Meta-study Synthesis of Qualitative Studies Evaluating Facilitators and Barriers to Participation in Colorectal Cancer Screening.

PubMed

Honein-AbouHaidar, Gladys N; Kastner, Monika; Vuong, Vincent; Perrier, Laure; Daly, Corinne; Rabeneck, Linda; Straus, Sharon; Baxter, Nancy N

2016-06-01

Screening reduces the incidence, morbidity, and mortality of colorectal cancer, yet participation tends to be low. We undertook a systematic review and meta-study synthesis of qualitative studies to identify facilitators and barriers to colorectal cancer screening participation. We searched major bibliographic databases for records published in all languages from inception to February 2015. Included primary studies that elicited views and perceptions towards colorectal cancer screening were appraised for relevance and quality. We used a two-stage synthesis to create an interpretation of colorectal cancer screening decisions grounded in primary studies; a thematic analysis to group themes and systematically compare studies and a meta-synthesis to generate an expanded theory of colorectal cancer screening participation. Ninety-four studies were included. The decision to participate in colorectal cancer screening depended on an individual's awareness of colorectal cancer screening. Awareness affected views of cancer, attitudes towards colorectal cancer screening modalities, and motivation for screening. Factors mediating awareness included public education to address misconceptions, primary care physician efforts to recommend screening, and the influence of friends and family. Specific barriers to participation in populations with lower participation rates included language barriers, logistical challenges to attending screening tests, and cultural beliefs. This study identifies key barriers, facilitators, and mediators to colorectal cancer screening participation. Cancer Epidemiol Biomarkers Prev; 25(6); 907-17. ©2016 AACR. ©2016 American Association for Cancer Research.

Computational Methods in Drug Discovery

PubMed Central

Sliwoski, Gregory; Kothiwale, Sandeepkumar; Meiler, Jens

2014-01-01

Computer-aided drug discovery/design methods have played a major role in the development of therapeutically important small molecules for over three decades. These methods are broadly classified as either structure-based or ligand-based methods. Structure-based methods are in principle analogous to high-throughput screening in that both target and ligand structure information is imperative. Structure-based approaches include ligand docking, pharmacophore, and ligand design methods. The article discusses theory behind the most important methods and recent successful applications. Ligand-based methods use only ligand information for predicting activity depending on its similarity/dissimilarity to previously known active ligands. We review widely used ligand-based methods such as ligand-based pharmacophores, molecular descriptors, and quantitative structure-activity relationships. In addition, important tools such as target/ligand data bases, homology modeling, ligand fingerprint methods, etc., necessary for successful implementation of various computer-aided drug discovery/design methods in a drug discovery campaign are discussed. Finally, computational methods for toxicity prediction and optimization for favorable physiologic properties are discussed with successful examples from literature. PMID:24381236

[Analysis of syndrome discipline of generalized anxiety disorder using data mining techniques].

PubMed

Tang, Qi-sheng; Sun, Wen-jun; Qu, Miao; Guo, Dong-fang

2012-09-01

To study the use of data mining techniques in analyzing the syndrome discipline of generalized anxiety disorder (GAD). From August 1, 2009 to July 31, 2010, 705 patients with GAD in 10 hospitals of Beijing were investigated over one year. Data mining techniques, such as Bayes net and cluster analysis, were used to analyze the syndrome discipline of GAD. A total of 61 symptoms of GAD were screened out. By using Bayes net, nine syndromes of GAD were abstracted based on the symptoms. Eight syndromes were abstracted by cluster analysis. After screening for duplicate syndromes and combining the experts' experience and traditional Chinese medicine theory, six syndromes of GAD were defined. These included depressed liver qi transforming into fire, phlegm-heat harassing the heart, liver depression and spleen deficiency, heart-kidney non-interaction, dual deficiency of the heart and spleen, and kidney deficiency and liver yang hyperactivity. Based on the results, the draft of Syndrome Diagnostic Criteria for Generalized Anxiety Disorder was developed. Data mining techniques such as Bayes net and cluster analysis have certain future potential for establishing syndrome models and analyzing syndrome discipline, thus they are suitable for the research of syndrome differentiation.

Strong quantum coherence between Fermi liquid Mahan excitons

DOE PAGES

Paul, J.; Stevens, C. E.; Liu, C.; ...

2016-04-14

In modulation doped quantum wells, the excitons are formed as a result of the interactions of the charged holes with the electrons at the Fermi edge in the conduction band, leading to the so-called “Mahan excitons.” The binding energy of Mahan excitons is expected to be greatly reduced and any quantum coherence destroyed as a result of the screening and electron-electron interactions. Surprisingly, we observe strong quantum coherence between the heavy hole and light hole excitons. Such correlations are revealed by the dominating cross-diagonal peaks in both one-quantum and two-quantum two-dimensional Fourier transform spectra. Theoretical simulations based on the opticalmore » Bloch equations where many-body effects are included phenomenologically reproduce well the experimental spectra. Furthermore, time-dependent density functional theory calculations provide insight into the underlying physics and attribute the observed strong quantum coherence to a significantly reduced screening length and collective excitations of the many-electron system.« less

Evaluation of a "loss-framed" minimal intervention to increase mammography utilization among medically un- and under-insured women.

PubMed

Abood, Doris A; Coster, Daniel C; Mullis, Ann K; Black, David R

2002-01-01

This study was conducted because mammography is under-utilized, even though it is the most effective early detection screening device for breast cancer. A loss-framed telephonic message based on prospect theory was evaluated for the effects on mammography utilization among medically un- and under-insured women living in demographically similar rural counties in Florida. The sample consisted mostly of White women (approximately 89%) 50-64 years old. Experimental group participants received the loss-framed message telephonically and those in the comparison group received the "usual telephone procedure." Logistic regression analyses revealed that women who received the loss-framed message were six times more likely to obtain a mammogram (OR = 6.6, P < 0.0001). The impact of the loss-framed message persisted even after adjustment for initial versus re-screen mammogram effects. This in-reach, loss-framed, minimal intervention seems to have viability and may serve as an alternative or adjunct program for encouraging women to receive mammograms.

Theory analysis for Pender's health promotion model (HPM) by Barnum's criteria: a critical perspective.

PubMed

Khoshnood, Zohreh; Rayyani, Masoud; Tirgari, Batool

2018-01-13

Background Analysis of nursing theoretical works and its role in knowledge development is presented as an essential process of critical reflection. Health promotion model (HPM) focuses on helping people achieve higher levels of well-being and identifies background factors that influence health behaviors. Objectives This paper aims to evaluate, and critique HPM by Barnum's criteria. Methods The present study reviewed books and articles derived from Proquest, PubMed, Blackwell Databases. The method of evaluation for this model is based on Barnum's criteria for analysis, application and evaluation of nursing theories. The criteria selected by Barnum embrace both internal and external criticism. Internal criticism deals with how theory components fit with each other (internal construction of theory) and external criticism deals with the way in which theory relates to the extended world (which considers theory in its relationships to human beings, nursing, and health). Results The electronic database search yielded over 27,717 titles and abstracts. Following removal of duplicates, 18,963 titles and abstracts were screened using the inclusion criteria and 1278 manuscripts were retrieved. Of these, 80 were specific to HPM and 23 to analysis of any theory in nursing relating to the aim of this article. After final selection using the inclusion criteria for this review, 28 manuscripts were identified as examining the factors contributing to theory analysis. Evaluation of health promotion theory showed that the philosophical claims and their content are consistent and clear. HPM has a logical structure and was applied to diverse age groups from differing cultures with varying health concerns. Conclusion In conclusion, among the strategies for theory critique, the Barnum approach is structured and accurate, considers theory in its relationship to human beings, community psychiatric nursing, and health. While according to Pender, nursing assessment, diagnosis and interventions are utilized to operationalize the HPM through practical application and research.

Plasma-screening effects on the electron-impact excitation of hydrogenic ions in dense plasmas

NASA Technical Reports Server (NTRS)

Jung, Young-Dae

1993-01-01

Plasma-screening effects are investigated on electron-impact excitation of hydrogenic ions in dense plasmas. Scaled cross sections Z(exp 4) sigma for 1s yields 2s and 1s yields 2p are obtained for a Debye-Hueckel model of the screened Coulomb interaction. Ground and excited bound wave functions are modified in the screened Coulomb potential (Debye-Hueckel model) using the Ritz variation method. The resulting atomic wave functions and their eigenenergies agree well with the numerical and high-order perturbation theory calculations for the interesting domain of the Debye length not less than 10. The Born approximation is used to describe the continuum states of the projectile electron. Plasma screening effects on the atomic electrons cannot be neglected in the high-density cases. Including these effects, the cross sections are appreciably increased for 1s yields 2s transitions and decreased for 1s yields 2p transitions.

Gravitational anti-screening as an alternative to dark matter

NASA Astrophysics Data System (ADS)

Penner, A. Raymond

2016-04-01

A semiclassical model of the screening of electric charge by virtual electric dipoles, as found in electrodynamic theory, will be presented. This model is then applied to the hypothetical case of an electric force where like charges attract. The resulting anti-screening of the electric charge is found to have the same functional dependence on the field source and observation distance that is found with the Baryonic Tully-Fisher Relationship. This leads to an anti-screening model for the gravitational force which is then used to determine the theoretical rotational curve of the Galaxy and the theoretical velocity dispersions and shear values for the Coma cluster. These theoretical results are found to be in good agreement with the corresponding astronomical observations. The screening of electric charge as found in QED and the larger apparent masses of galaxies and galactic clusters therefore appears to be two sides of the same coin.

Interventions to Promote Colorectal Cancer Screening: An Integrative Review

PubMed Central

Rawl, Susan M.; Menon, Usha; Burness, Allison; Breslau, Erica S.

2012-01-01

Behavior change interventions to promote colorectal cancer (CRC) screening have targeted people in community and primary care settings, health care providers, and health systems. Randomized controlled trials provide the strongest evidence of intervention efficacy. The purpose of this integrative review was to evaluate trials of CRC screening interventions published between 1997 and 2007 and to identify knowledge gaps and future directions for research. Thirty-three randomized trials that met inclusion criteria were evaluated using a modified version of the TREND criteria. Significant intervention effects were reported in six out of ten trials focused on increasing fecal occult blood testing, four of seven trials focused on sigmoidoscopy or colonoscopy completion, and nine of 16 focused on completion of any screening test. Several effective interventions to promote CRC screening were identified. Future trials need to use theory to guide interventions, examine moderators and mediators, consistently report results, and use comparable outcome measures. PMID:22261002

The Electrostatic Screening Length in Concentrated Electrolytes Increases with Concentration.

PubMed

Smith, Alexander M; Lee, Alpha A; Perkin, Susan

2016-06-16

According to classical electrolyte theories interactions in dilute (low ion density) electrolytes decay exponentially with distance, with the Debye screening length the characteristic length scale. This decay length decreases monotonically with increasing ion concentration due to effective screening of charges over short distances. Thus, within the Debye model no long-range forces are expected in concentrated electrolytes. Here we reveal, using experimental detection of the interaction between two planar charged surfaces across a wide range of electrolytes, that beyond the dilute (Debye-Hückel) regime the screening length increases with increasing concentration. The screening lengths for all electrolytes studied-including aqueous NaCl solutions, ionic liquids diluted with propylene carbonate, and pure ionic liquids-collapse onto a single curve when scaled by the dielectric constant. This nonmonotonic variation of the screening length with concentration, and its generality across ionic liquids and aqueous salt solutions, demonstrates an important characteristic of concentrated electrolytes of substantial relevance from biology to energy storage.

Economic analysis of CDC's culture- and smear-based tuberculosis instructions for Filipino immigrants.

PubMed

Maskery, B; Posey, D L; Coleman, M S; Asis, R; Zhou, W; Painter, J A; Wingate, L T; Roque, M; Cetron, M S

2018-04-01

In 2007, the US Centers for Disease Control and Prevention (CDC) revised its tuberculosis (TB) technical instructions for panel physicians who administer mandatory medical examinations among US-bound immigrants. Many US-bound immigrants come from the Philippines, a high TB prevalence country. To quantify economic and health impacts of smear- vs. culture-based TB screening. Decision tree modeling was used to compare three Filipino screening programs: 1) no screening, 2) smear-based screening, and 3) culture-based screening. The model incorporated pre-departure TB screening results from Filipino panel physicians and CDC databases with post-arrival follow-up outcomes. Costs (2013 $US) were examined from societal, immigrant, US Public Health Department and hospitalization perspectives. With no screening, an annual cohort of 35 722 Filipino immigrants would include an estimated 450 TB patients with 264 hospitalizations, at a societal cost of US$9.90 million. Culture-based vs. smear-based screening would result in fewer imported cases (80.9 vs. 310.5), hospitalizations (19.7 vs. 68.1), and treatment costs (US$1.57 million vs. US$4.28 million). Societal screening costs, including US follow-up, were greater for culture-based screening (US$5.98 million) than for smear-based screening (US$3.38 million). Culture-based screening requirements increased immigrant costs by 61% (US$1.7 million), but reduced costs for the US Public Health Department (22%, US$750 000) and of hospitalization (70%, US$1 020 000). Culture-based screening reduced imported TB and US costs among Filipino immigrants.

The Preschool Activity, Technology, Health, Adiposity, Behaviour and Cognition (PATH-ABC) cohort study: rationale and design.

PubMed

Cliff, Dylan P; McNeill, Jade; Vella, Stewart; Howard, Steven J; Kelly, Megan A; Angus, Douglas J; Wright, Ian M; Santos, Rute; Batterham, Marijka; Melhuish, Edward; Okely, Anthony D; de Rosnay, Marc

2017-04-04

Prevalence estimates internationally suggest that many preschool-aged children (3-5 years) are insufficiently physically active and engage in high levels of screen-based entertainment. Early childhood is the developmental period for which we know the least about the effects of physical activity on development and health. Likewise, rapid technological advancements in mobile electronic media have made screen-based forms of entertainment for young children ubiquitous, and research demonstrating the impacts on cognition, psychosocial well-being, and health has lagged behind the rate of adoption of these technologies. The purpose of the Preschool Activity, Technology, Health, Adiposity, Behaviour and Cognition (PATH-ABC) study is to investigate if physical activity and screen-based entertainment are independently associated with cognitive and psychosocial development, and health outcomes in young children, and if so, how much and which types of these behaviours might be most influential. The PATH-ABC study is a prospective cohort, aiming to recruit 430 3-5 year-old children. Children are recruited through and complete initial assessments at their Early Childhood Education and Care (ECEC) centre, and then 12-months later at their centre or school. Direct assessments are made of children's habitual physical activity using accelerometry, cognitive (executive function) and language development (expressive vocabulary), psychosocial development (emotional understanding, Theory of Mind, empathy, and heart rate variability), adiposity (body mass index and waist circumference), and cardiovascular health (blood pressure and retinal micro- vasculature). Educators report on children's psychological strengths and difficulties and self-regulation. Parents report on children's habitual use of electronic media and other child, parent and household characteristics. The PATH-ABC study aims to provide evidence to enhance understanding of how much and which types of physical activity and screen-based media influence development and health in preschool-aged children. This information would benefit parents, educators, health professionals and governments seeking to develop strategies and policies to give young children the best start in life by promoting healthy levels of physical activity and electronic media use.

Relativistic corrections for screening effects on the energies of hydrogen-like atoms embedded in plasmas

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

Poszwa, A., E-mail: poszwa@matman.uwm.edu.p; Bahar, M. K., E-mail: mussiv58@gmail.com

2015-01-15

The influence of relativistic and plasma screening effects on energies of hydrogen-like atoms embedded in plasmas has been studied. The Dirac equation with a more general exponential cosine screened potential has been solved numerically and perturbatively, by employing the direct perturbation theory. Properties of spectra corresponding to bound states and to different sets of the potential parameters have been studied both in nonrelativistic and relativistic approximations. Binding energies, fine-structure splittings, and relativistic energy shifts have been determined as functions of parameters of the potential. The results have been compared with the ones known from the literature.

Toward Joint Hypothesis-Tests Seismic Event Screening Analysis: Ms|mb and Event Depth

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

Anderson, Dale; Selby, Neil

2012-08-14

Well established theory can be used to combine single-phenomenology hypothesis tests into a multi-phenomenology event screening hypothesis test (Fisher's and Tippett's tests). Commonly used standard error in Ms:mb event screening hypothesis test is not fully consistent with physical basis. Improved standard error - Better agreement with physical basis, and correctly partitions error to include Model Error as a component of variance, correctly reduces station noise variance through network averaging. For 2009 DPRK test - Commonly used standard error 'rejects' H0 even with better scaling slope ({beta} = 1, Selby et al.), improved standard error 'fails to rejects' H0.

The need for supplemental breast cancer screening modalities: a perspective of population-based breast cancer screening programs in Japan.

PubMed

Uematsu, Takayoshi

2017-01-01

This article discusses possible supplemental breast cancer screening modalities for younger women with dense breasts from a perspective of population-based breast cancer screening program in Japan. Supplemental breast cancer screening modalities have been proposed to increase the sensitivity and detection rates of early stage breast cancer in women with dense breasts; however, there are no global guidelines that recommend the use of supplemental breast cancer screening modalities in such women. Also, no criterion standard exists for breast density assessment. Based on the current situation of breast imaging in Japan, the possible supplemental breast cancer screening modalities are ultrasonography, digital breast tomosynthesis, and breast magnetic resonance imaging. An appropriate population-based breast cancer screening program based on the balance between cost and benefit should be a high priority. Further research based on evidence-based medicine is encouraged. It is very important that the ethnicity, workforce, workflow, and resources for breast cancer screening in each country should be considered when considering supplemental breast cancer screening modalities for women with dense breasts.

Using the Web as a Higher Order Thinking Partner: Case Study of an Advanced Learner Creatively Synthesizing Knowledge on the Web

ERIC Educational Resources Information Center

DeSchryver, Michael

2017-01-01

Previous work provided foundations for the theory of web-mediated knowledge synthesis, a framework for using the web in more creative and generative ways. This article explores specific instances of the various elements of that theory in a single case from the initial study. That is, a thorough exploration of think-aloud, screen capture, and…

Thermodynamic screening of metal-substituted MOFs for carbon capture.

PubMed

Koh, Hyun Seung; Rana, Malay Kumar; Hwang, Jinhyung; Siegel, Donald J

2013-04-07

Metal-organic frameworks (MOFs) have emerged as promising materials for carbon capture applications due to their high CO2 capacities and tunable properties. Amongst the many possible MOFs, metal-substituted compounds based on M-DOBDC and M-HKUST-1 have demonstrated amongst the highest CO2 capacities at the low pressures typical of flue gasses. Here we explore the possibility for additional performance tuning of these compounds by computationally screening 36 metal-substituted variants (M = Be, Mg, Ca, Sr, Sc, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Mo, W, Sn, and Pb) with respect to their CO2 adsorption enthalpy, ΔH(T=300K). Supercell calculations based on van der Waals density functional theory (vdW-DF) yield enthalpies in good agreement with experimental measurements, out-performing semi-empirical (DFT-D2) and conventional (LDA & GGA) functionals. Our screening identifies 13 compounds having ΔH values within the targeted thermodynamic window -40 ≤ ΔH ≤ -75 kJ mol(-1): 8 are based on M-DODBC (M = Mg, Ca, Sr, Sc, Ti, V, Mo, and W), and 5 on M-HKUST-1 (M = Be, Mg, Ca, Sr and Sc). Variations in the electronic structure and the geometry of the structural building unit are examined and used to rationalize trends in CO2 affinity. In particular, the partial charge on the coordinatively unsaturated metal sites is found to correlate with ΔH, suggesting that this property may be used as a simple performance descriptor. The ability to rapidly distinguish promising MOFs from those that are "thermodynamic dead-ends" will be helpful in guiding synthesis efforts towards promising compounds.

Excitonic instability in optically pumped three-dimensional Dirac materials

NASA Astrophysics Data System (ADS)

Pertsova, Anna; Balatsky, Alexander V.

2018-02-01

Recently it was suggested that transient excitonic instability can be realized in optically pumped two-dimensional (2D) Dirac materials (DMs), such as graphene and topological insulator surface states. Here we discuss the possibility of achieving a transient excitonic condensate in optically pumped three-dimensional (3D) DMs, such as Dirac and Weyl semimetals, described by nonequilibrium chemical potentials for photoexcited electrons and holes. Similar to the equilibrium case with long-range interactions, we find that for pumped 3D DMs with screened Coulomb potential two possible excitonic phases exist, an excitonic insulator phase and the charge density wave phase originating from intranodal and internodal interactions, respectively. In the pumped case, the critical coupling for excitonic instability vanishes; therefore the two phases coexist for arbitrarily weak coupling strengths. The excitonic gap in the charge density wave phase is always the largest one. The competition between screening effects and the increase of the density of states with optical pumping results in a rich phase diagram for the transient excitonic condensate. Based on the static theory of screening, we find that under certain conditions the value of the dimensionless coupling constant screening in 3D DMs can be weaker than in 2D DMs. Furthermore, we identify the signatures of the transient excitonic condensate that could be probed by scanning tunneling spectroscopy, photoemission, and optical conductivity measurements. Finally, we provide estimates of critical temperatures and excitonic gaps for existing and hypothetical 3D DMs.

System theory in medical diagnostic devices: an overview.

PubMed

Baura, Gail D

2006-01-01

Medical diagnostics refers to testing conducted either in vitro or in vivo to provide critical health care information for risk assessment, early diagnosis, treatment, or disease management. Typical in vivo diagnostic tests include the computed tomography scan, magnetic resonance imaging, and blood pressure screening. Typical in vitro diagnostic tests include cholesterol, Papanicolaou smear, and conventional glucose monitoring tests. Historically, devices associated with both types of diagnostics have used heuristic curve fitting during signal analysis. However, since the early 1990s, a few enterprising engineers and physicians have used system theory to improve their core processing for feature detection and system identification. Current applications include automated Pap smear screening for detection of cervical cancer and diagnosis of Alzheimer's disease. Future applications, such as disease prediction before symptom onset and drug treatment customization, have been catalyzed by the Human Genome Project.

Carrier screening for single gene disorders.

PubMed

Rose, Nancy C; Wick, Myra

2018-04-01

Screening for genetic disorders began in 1963 with the initiation of newborn screening for phenylketonuria. Advances in molecular technology have made both newborn screening for newborns affected with serious disorders, and carrier screening of individuals at risk for offspring with genetic disorders, more complex and more widely available. Carrier screening today can be performed secondary to family history-based screening, ethnic-based screening, and expanded carrier screening (ECS). ECS is panel-based screening, which analyzes carrier status for hundreds of genetic disorders irrespective of patient race or ethnicity. In this article, we review the historical and current aspects of carrier screening for single gene disorders, including future research directions. Copyright © 2017 Elsevier Ltd. All rights reserved.

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

Burrage, Clare; Copeland, Edmund J.; Hinds, E.A., E-mail: Clare.Burrage@nottingham.ac.uk, E-mail: Edmund.Copeland@nottingham.ac.uk, E-mail: Ed.Hinds@imperial.ac.uk

Theories of dark energy require a screening mechanism to explain why the associated scalar fields do not mediate observable long range fifth forces. The archetype of this is the chameleon field. Here we show that individual atoms are too small to screen the chameleon field inside a large high-vacuum chamber, and therefore can detect the field with high sensitivity. We derive new limits on the chameleon parameters from existing experiments, and show that most of the remaining chameleon parameter space is readily accessible using atom interferometry.

Solution of electromagnetic scattering and radiation problems using a spectral domain approach - A review

NASA Technical Reports Server (NTRS)

Mittra, R.; Ko, W. L.; Rahmat-Samii, Y.

1979-01-01

This paper presents a brief review of some recent developments on the use of the spectral-domain approach for deriving high-frequency solutions to electromagnetics scattering and radiation problems. The spectral approach is not only useful for interpreting the well-known Keller formulas based on the geometrical theory of diffraction (GTD), it can also be employed for verifying the accuracy of GTD and other asymptotic solutions and systematically improving the results when such improvements are needed. The problem of plane wave diffraction by a finite screen or a strip is presented as an example of the application of the spectral-domain approach.

Ab initio study of energy transfer rates and impact sensitivities of crystalline explosives.

PubMed

Bernstein, Jonathan

2018-02-28

Impact sensitivities of various crystalline explosives were predicted by means of plane wave-density functional theory calculations. Crystal structures and complete vibrational spectra of TATB, PETN, FOX7, TEX, 14DNI, and β-HMX molecular crystals were calculated. A correlation between the phonon-vibron coupling (which is proportionally related to the energy transfer rate between the phonon manifold and the intramolecular vibrational modes) and impact sensitivities of secondary explosives was found. We propose a method, based on ab initio calculations, for the evaluation of impact sensitivities, which consequently can assist in screening candidates for chemical synthesis of high energetic materials.

Doping effects in InN/GaN short-period quantum well structures-Theoretical studies based on density functional methods

NASA Astrophysics Data System (ADS)

Strak, Pawel; Kempisty, Pawel; Sakowski, Konrad; Krukowski, Stanislaw

2014-09-01

Density functional theory studies were conducted to determine an influence of the carrier concentration on the optical and electronic properties of InN/GaN superlattice system. The oscillator strength values, energy gaps and the band profiles were obtained. The band profiles were found to be strongly affected for technically possible heavy n-type doping while for p-type doping the carrier influence, both screening and band shift, is negligible. Blue shift of the transition energy between conduction band minima and valence band maxima was observed for high concentrations of both type carriers.

On the Problem of Filtration to an Imperfect Gallery in a Pressureless Bed

NASA Astrophysics Data System (ADS)

Bereslavskii, É. N.; Dudina, L. M.

2018-01-01

The problem of plane steady-state filtration in a pressureless bed to an imperfect gallery in the presence of evaporation from the flow free surface is considered. To study such type of flow, a mixed boundary-value problem of the theory of analytical functions is formulated and solved with application of the Polubarinova-Kochina method. Based on the model suggested, an algorithm for computing the discharge of the gallery and the ordinate of free surface emergence to the impermeable screen is developed. A detailed hydrodynamic analysis of the influence of all physical parameters of the model on the desired filtration characteristics is given.

Ab initio study of energy transfer rates and impact sensitivities of crystalline explosives

NASA Astrophysics Data System (ADS)

Bernstein, Jonathan

2018-02-01

Impact sensitivities of various crystalline explosives were predicted by means of plane wave-density functional theory calculations. Crystal structures and complete vibrational spectra of TATB, PETN, FOX7, TEX, 14DNI, and β-HMX molecular crystals were calculated. A correlation between the phonon-vibron coupling (which is proportionally related to the energy transfer rate between the phonon manifold and the intramolecular vibrational modes) and impact sensitivities of secondary explosives was found. We propose a method, based on ab initio calculations, for the evaluation of impact sensitivities, which consequently can assist in screening candidates for chemical synthesis of high energetic materials.

Optimization of a hybrid exchange-correlation functional for silicon carbides

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

Oda, Takuji; Zhang, Yanwen; Weber, William J

2013-01-01

A hybrid exchange-correlation functional is optimized in order to accurately describe the nature of silicon carbides (SiC) in the framework of ab-initio calculations based on density functional theory (DFT), especially with an aim toward future applications in defect studies. It is shown that the Heyd-Scuseria-Ernzerhof (HSE) hybrid functional with the screening parameter of 0.15 -1 outperforms conventional exchange-correlation functionals and other popular hybrid functionals regarding description of band structures in SiC. High transferability is proven through assessment over various SiC polytypes, silicon and diamond. Excellent performance is also confirmed for other fundamental material properties including elastic constants and phonon frequency.

Photons in dense nuclear matter: Random-phase approximation

NASA Astrophysics Data System (ADS)

Stetina, Stephan; Rrapaj, Ermal; Reddy, Sanjay

2018-04-01

We present a comprehensive and pedagogic discussion of the properties of photons in cold and dense nuclear matter based on the resummed one-loop photon self-energy. Correlations among electrons, muons, protons, and neutrons in β equilibrium that arise as a result of electromagnetic and strong interactions are consistently taken into account within the random phase approximation. Screening effects, damping, and collective excitations are systematically studied in a fully relativistic setup. Our study is relevant to the linear response theory of dense nuclear matter, calculations of transport properties of cold dense matter, and investigations of the production and propagation of hypothetical vector bosons such as the dark photons.

Use of protection motivation theory, affect, and barriers to understand and predict adherence to outpatient rehabilitation.

PubMed

Grindley, Emma J; Zizzi, Samuel J; Nasypany, Alan M

2008-12-01

Protection motivation theory (PMT) has been used in more than 20 different health-related fields to study intentions and behavior, albeit primarily outside the area of injury rehabilitation. In order to examine and predict patient adherence behavior, this study was carried out to explore the use of PMT as a screening tool in a general sample of people with orthopedic conditions. New patients who were more than 18 years old and who were prescribed 4 to 8 weeks of physical therapy treatment (n=229) were administered a screening tool (Sports Injury Rehabilitation Beliefs Scale, Positive and Negative Affect Schedule, and a barriers checklist) prior to treatment. Participants' adherence was assessed with several attendance measures and an in-clinic assessment of behavior. Statistical analyses included correlation, chi-square, multiple regression, and discriminant function analyses. A variety of relationships among affect, barriers, and PMT components were evident. In-clinic behavior and attendance were influenced by affect, whereas dropout status was predicted by affect, severity, self-efficacy, and age. The screening tool used in this study may assist in identifying patients who are at risk for poor adherence and provide valuable information to enhance provider-patient relationships and foster patient adherence. However, it is recommended that more research be conducted to further understand the impact of variables on patient adherence and that the screening tool be enhanced to increase its predictive ability.

Colorectal cancer screening: The role of the noninvasive options.

PubMed

Dickerson, Lisa; Varcak, Susan Combs

2016-09-01

Recommended screening options for colorectal cancer are divided into noninvasive stool-based options, and invasive procedure-based options. Because multiple screening strategies are effective, efforts to reduce deaths from colorectal cancer should focus on maximizing the number of patients who are screened. This article reviews noninvasive stool-based screening options.

Explaining the food safety behaviours of food handlers using theories of behaviour change: a systematic review.

PubMed

Young, Ian; Thaivalappil, Abhinand; Greig, Judy; Meldrum, Richard; Waddell, Lisa

2018-06-01

Theories of behaviour change can explain the factors affecting food handlers' use of food safety practices. A systematic review was conducted on this topic to identify which theories have been applied in this area and to determine which theories are the most consistent predictors of food handlers' behaviours. Standard systematic review procedures were followed: comprehensive search strategy; relevance screening of abstracts; article characterization; data extraction; risk-of-bias assessment; and descriptive analysis. Among 19 relevant studies, the most commonly investigated theories were the Theory of Planned Behaviour (n = 9 studies) and Health Belief Model (n = 5). All investigated theories were useful to explain food handlers' behavioural intentions and behaviours related to food safety across different settings, and could serve as useful frameworks for future research and practice. However, there was wide variability in the predictive ability of the theories and their specific constructs, indicating theories should be adapted to the local context of application.

Facing possible illness detected through screening--experiences of healthy women with pathological cervical smears.

PubMed

Hounsgaard, Lise; Petersen, Lone Kjeld; Pedersen, Birthe D

2007-12-01

The aim of this study is to gain knowledge about women's perceptions of illness based on their abnormal PAP smears, following screening for cervical cancer. The study uses a phenomenological, hermeneutic approach inspired by Ricoeur's theory of interpretation. Twelve women, aged between 23 and 59 years, were consecutively selected and then followed by participant observation during their examinations and treatment in hospital. They were interviewed on entering the study, a week following their surgery, and 6 months later. The material collected was analysed through a dialectic process consisting of a face-value review of participant experiences (naive reading), structural analysis and, critical interpretation of what it means to be potentially ill. The women were unprepared to find that their screening results showed abnormal cells, indicative of incipient genital cancer. They were frustrated by the results as they had not experienced any symptoms and felt well, despite being diagnosed with a potential disease. Being diagnosed with abnormal cells caused the participants to feel anxious. Their anxiety had subsided 6 months after the cells had been removed. For those who did not require treatment, anxiety flared up with recurrent check-ups. The bio-medical differentiation between pre-stage and actual cancer provided no comfort to the participants, who continued to see themselves as having early stage cancer.

Bulk-surface relationship of an electronic structure for high-throughput screening of metal oxide catalysts

NASA Astrophysics Data System (ADS)

Kweun, Joshua Minwoo; Li, Chenzhe; Zheng, Yongping; Cho, Maenghyo; Kim, Yoon Young; Cho, Kyeongjae

2016-05-01

Designing metal-oxides consisting of earth-abundant elements has been a crucial issue to replace precious metal catalysts. To achieve efficient screening of metal-oxide catalysts via bulk descriptors rather than surface descriptors, we investigated the relationship between the electronic structure of bulk and that of the surface for lanthanum-based perovskite oxides, LaMO3 (M = Ti, V, Cr, Mn, Fe, Co, Ni, Cu). Through density functional theory calculations, we examined the d-band occupancy of the bulk and surface transition-metal atoms (nBulk and nSurf) and the adsorption energy of an oxygen atom (Eads) on (001), (110), and (111) surfaces. For the (001) surface, we observed strong correlation between the nBulk and nSurf with an R-squared value over 94%, and the result was interpreted in terms of ligand field splitting and antibonding/bonding level splitting. Moreover, the Eads on the surfaces was highly correlated with the nBulk with an R-squared value of more than 94%, and different surface relaxations could be explained by the bulk electronic structure (e.g., LaMnO3 vs. LaTiO3). These results suggest that a bulk-derived descriptor such as nBulk can be used to screen metal-oxide catalysts.

Can a decision aid enable informed decisions in neonatal nursery recruitment for a fragile X newborn screening study?

PubMed

Bailey, Donald B; Bann, Carla; Bishop, Ellen; Guarda, Sonia; Barnum, Leah; Roche, Myra

2013-04-01

To determine whether a brochure based on principles of informed decision making improved attention to study materials or altered decisions made by parents invited to participate in a fragile X syndrome newborn screening study. A total of 1,323 families were invited to participate in a newborn screening study to identify infants with fragile X syndrome as well as premutation carrier infants. Of these families, 716 received the original project brochure and 607 were given a new decision aid brochure. Families were more likely to look at the new decision aid and mothers were more likely to read it completely, but the proportion of mothers who read the entire decision aid was only 14%. Families were more likely to rate the decision aid as very helpful. Consistent with informed decision making theory and research, participants receiving the decision aid brochure were less likely to agree to participate. The decision aid increased attention to and perceived helpfulness of educational information about the study, but most families did not read it completely. The study suggests that even well-designed study materials are not fully reviewed in the context of in-hospital postpartum study recruitment and may need to be accompanied by a research recruiter to obtain informed consent.

Point-Counterpoint: Active surveillance for carriers of toxigenic Clostridium difficile should be performed to guide prevention efforts.

PubMed

McDonald, L Clifford; Diekema, Daniel J

2018-05-16

In 2017, we published a point-counterpoint on laboratory diagnosis of C. difficile infection (CDI). At that time, Drs Ferric Fang, Christopher Polage, and Mark Wilcox discussed the strategies for diagnosing Clostridium difficile colitis in symptomatic patients. Since that manuscript new guidelines from the Infectious Diseases Society of American and the Society for Health Care Epidemiology have been published (1) and healthcare systems have begun to explore screening asymptomatic patients for C. difficile colonization. The theory behind screening selected patient populations for C. difficile colonization is that these patients represent a substantial reservoir of the bacteria and can transfer the bacteria to other patients. Hospital administrators are taking note of institutional CDI rates because they are publicly reported. They have become an important metric impacting hospital safety ratings and value-based purchasing where hospitals may have millions of dollars of reimbursement at risk. In this point-counterpoint, Cliff McDonald, of the U.S. Centers for Disease Control and Prevention, will discuss the value of asymptomatic C. difficile screening, while Dan Diekema, of the University of Iowa, will discuss why caution should be used. This is a work of the U.S. Government and is not subject to copyright protection in the United States. Foreign copyrights may apply.

Attitudes and beliefs among high- and low-risk population groups towards β-thalassemia prevention: a cross-sectional descriptive study from India.

PubMed

Chawla, Swati; Singh, Rajnish Kumar; Lakkakula, Bhaskar V K S; Vadlamudi, Raghavendra Rao

2017-07-01

β-thalassemia is an autosomal recessive blood disorder caused by gene mutations that affect all aspects of β-globin production. In majority of Asian countries including India, the frequency of β-thalassemia is closely intertwined with social, cultural, and religious issues of the respective country. Several national level screening programs imparted education regarding β-thalassemia, but follow-up evaluation revealed that education was not effective. It has been hypothesized that the beliefs and attitudes, carrier screening, and education among "high risk communities" will have far-reaching implications towards β-thalassemia prevention in the country. The present study is aimed to investigate attitudes, intention, and behavior of β-thalassemia high- and low-risk ethnic groups towards carrier screening and education. A structured questionnaire on knowledge, attitude, and practice regarding β-thalassemia was administered on 926 individuals belong to Arora, a high-risk ethnic group for β-thalassemia (347 rural (AR) and 202 urban (AU)) and 377 cosmopolitan commoners (CC) aged above 18 years of both sexes. To understand the relationship between various questions, Pearson's correlation test and factor analysis was performed. The responses were further categorized into the theory of planned behavior (TPB) constructs with the measures of the main constructs reported as a mean. Various dimensions of knowledge, attitude, and practice reveal that the urban groups (AU and CC) are better aware of the disease "β-thalassemia" than the rural group (AR) who witness suffering at close quarters. The AR group is more positive for preventive measures than the urban groups. Significant correlations and factor analysis show "intentions" for premarital and prenatal screening highly loaded as outcome behaviors. The Ajzen's "Theory of planned behavior" support that the "intention" and "perceived behavior control" are better predictors of "outcome behavior" compared to "attitude" and "subjective norm." As this study is cross-sectional and descriptive in nature, the constructs of the theory should be considered as perceptions. However, we believe the patterns observed are indicative of "predicting behavior" that has far-reaching implications on health planners and administrators in designing β-thalassemia screening and prevention program.

Benzophenone based fluorophore for selective detection of Sn2+ ion: Experimental and theoretical study.

PubMed

Jadhav, Amol G; Shinde, Suvidha S; Lanke, Sandip K; Sekar, Nagaiyan

2017-03-05

Synthesis of novel benzophenone-based chemosensor is presented for the selective sensing of Sn 2+ ion. Screening of competitive metal ions was performed by competitive experiments. The specific cation recognition ability of chemosensor towards Sn 2+ was investigated by experimental (UV-visible, fluorescence spectroscopy, 1 H NMR, 13 C NMR, FTIR and HRMS) methods and further supported by Density Functional Theory study. The stoichiometric binding ratio and binding constant (K a ) for complex is found to be 1:1 and 1.50×10 4 , respectively. The detection limit of Sn 2+ towards chemosensor was found to be 0.3898ppb. Specific selectivity and superiority of chemosensor over another recently reported chemosensor is presented. Copyright © 2016 Elsevier B.V. All rights reserved.

Cosmic web and environmental dependence of screening: Vainshtein vs. chameleon

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

Falck, Bridget; Koyama, Kazuya; Zhao, Gong-Bo, E-mail: bridget.falck@port.ac.uk, E-mail: kazuya.koyama@port.ac.uk, E-mail: gong-bo.zhao@port.ac.uk

Theories which modify general relativity to explain the accelerated expansion of the Universe often use screening mechanisms to satisfy constraints on Solar System scales. We investigate the effects of the cosmic web and the local environmental density of dark matter halos on the screening properties of the Vainshtein and chameleon screening mechanisms. We compare the cosmic web morphology of dark matter particles, mass functions of dark matter halos, mass and radial dependence of screening, velocity dispersions and peculiar velocities, and environmental dependence of screening mechanisms in f(R) and nDGP models. Using the ORIGAMI cosmic web identification routine we find thatmore » the Vainshtein mechanism depends on the cosmic web morphology of dark matter particles, since these are defined according to the dimensionality of their collapse, while the chameleon mechanism shows no morphology dependence. The chameleon screening of halos and their velocity dispersions depend on halo mass, and small halos and subhalos can be environmentally screened in the chameleon mechanism. On the other hand, the screening of halos in the Vainshtein mechanism does not depend on mass nor environment, and their velocity dispersions are suppressed. The peculiar velocities of halos in the Vainshtein mechanism are enhanced because screened objects can still feel the fifth force generated by external fields, while peculiar velocities of chameleon halos are suppressed when the halo centers are screened.« less

Mediation of the Physical Activity and Healthy Nutrition Behaviors of Preschool Children by Maternal Cognition in China

PubMed Central

Xu, Xianglong; Sharma, Manoj; Liu, Lingli; Hu, Ping; Zhao, Yong

2016-01-01

(1) Objective: We aimed to explore the role of social cognitive theory (SCT) of mothers in the physical activity and healthy nutrition behaviors of preschool children; (2) Methods: We used a self-administered five-point Likert common physical activity and nutrition behaviors scale in Chinese based on a social cognitive theory scale in English with established validity and reliability in the USA. The current study adopted the proportional sampling method to survey mothers of preschool children in four areas—namely, Chongqing, Chengdu, Taiyuan, and Shijiazhuang—of China; (3) Results: We included 1208 mothers (80.0% mothers of normal weight children, age 31.87 ± 4.19 years). Positive correlations were found between maternal social cognition and preschool children’s physical activity (PA) behavior (p < 0.0001). However, an insignificant correlation is observed between preschool children’s fruits and vegetables (FV) behavior, screen time (ST) behavior, and maternal social cognition; (4) Conclusions: This study provides some implications for increasing fruit and vegetable consumption, increasing physical activity time, and reducing screen time in preschool children using SCT in China. Maternal social cognition is associated with preschool children’s PA behavior, and the results suggest that maternal social cognition may not affect children FV and ST behaviors. Further research is necessary to test the mediation of maternal social cognition on preschool children’s ST behavior and the correlations between maternal social cognition and children’s ST behavior. PMID:27649215

[Establishment of prescription research technology system in Chinese medicine secondary exploitation based on "component structure" theory].

PubMed

Cheng, Xu-Dong; Feng, Liang; Gu, Jun-Fei; Zhang, Ming-Hua; Jia, Xiao-Bin

2014-11-01

Chinese medicine prescriptions are the wisdom outcomes of traditional Chinese medicine (TCM) clinical treatment determinations which based on differentiation of symptoms and signs. Chinese medicine prescriptions are also the basis of secondary exploitation of TCM. The study on prescription helps to understand the material basis of its efficacy, pharmacological mechanism, which is an important guarantee for the modernization of traditional Chinese medicine. Currently, there is not yet dissertation n the method and technology system of basic research on the prescription of Chinese medicine. This paper focuses on how to build an effective system of prescription research technology. Based on "component structure" theory, a technology system contained four-step method that "prescription analysis, the material basis screening, the material basis of analysis and optimization and verify" was proposed. The technology system analyzes the material basis of the three levels such as Chinese medicine pieces, constituents and the compounds which could respect the overall efficacy of Chinese medicine. Ideas of prescription optimization, remodeling are introduced into the system. The technology system is the combination of the existing research and associates with new techniques and methods, which used for explore the research thought suitable for material basis research and prescription remodeling. The system provides a reference for the secondary development of traditional Chinese medicine, and industrial upgrading.

Risk-based screening for Chlamydia trachomatis and Neisseria gonorrhoeae prior to intrauterine device insertion.

PubMed

Grentzer, Jaclyn M; Peipert, Jeffrey F; Zhao, Qiuhong; McNicholas, Colleen; Secura, Gina M; Madden, Tessa

2015-10-01

The objective was to compare three strategies for Chlamydia trachomatis and Neisseria gonorrhoeae screening prior to intrauterine device (IUD) insertion. This was a secondary analysis of the Contraceptive CHOICE Project. We measured the prevalence of C. trachomatis and/or N. gonorrhoeae at the time of IUD insertion. We then compared sensitivity, specificity, negative and positive predictive values, and likelihood ratios for three screening strategies for C. trachomatis and N. gonorrhoeae prior to IUD insertion: (a) "age-based" — age ≤25 years alone; (b) "age/partner-based" — age ≤25 and/or multiple sexual partners; and (c) "risk-based" — age ≤25, multiple sexual partners, inconsistent condom use and/or history of prior sexually transmitted infection (STI). Among 5087 IUD users, 140 (2.8%) tested positive for C. trachomatis, 16 (0.3%) tested positive for N. gonorrhoeae, and 6 (0.1%) were positive for both at the time of IUD insertion. The "risk-based" screening strategy had the highest sensitivity (99.3%) compared to "age-based" and "age/partner-based" screening (80.7% and 84.7%, respectively.) Only one (0.7%) woman with a chlamydia or gonorrhea infection would not have been screened using "risk-based" screening. A risk-based strategy to screen for C. trachomatis and N. gonorrhoeae prior to IUD insertion has higher sensitivity than screening based on age alone or age and multiple sexual partners. Using a risk-based screening strategy (age≤25, multiple sexual partners, inconsistent condom use and/or history of an STI) to determine who should be screened for C. trachomatis and N. gonorrhoeae prior to IUD insertion will miss very few cases of infection and obviates the need for universal screening. Copyright © 2015 Elsevier Inc. All rights reserved.

Prostate-specific antigen-based prostate cancer screening: Past and future.

PubMed

Alberts, Arnout R; Schoots, Ivo G; Roobol, Monique J

2015-06-01

Prostate-specific antigen-based prostate cancer screening remains a controversial topic. Up to now, there is worldwide consensus on the statement that the harms of population-based screening, mainly as a result of overdiagnosis (the detection of clinically insignificant tumors that would have never caused any symptoms), outweigh the benefits. However, worldwide opportunistic screening takes place on a wide scale. The European Randomized Study of Screening for Prostate Cancer showed a reduction in prostate cancer mortality through prostate-specific antigen based-screening. These population-based data need to be individualized in order to avoid screening in those who cannot benefit and start screening in those who will. For now, lacking a more optimal screening approach, screening should only be started after the process of shared decision-making. The focus of future research is the reduction of unnecessary testing and overdiagnosis by further research to better biomarkers and the value of the multiparametric magnetic resonance imaging, potentially combined in already existing prostate-specific antigen-based multivariate risk prediction models. © 2015 The Japanese Urological Association.

A Feasibility and Efficacy Randomized Controlled Trial of an Online Preventative Program for Childhood Obesity: Protocol for the EMPOWER Intervention

PubMed Central

Sharma, Manoj

2012-01-01

Background: The home and family environment is a highly influential psychosocial antecedent of pediatric obesity. Implementation of conventional family- and home-based childhood obesity interventions is challenging for parents, often requiring them to attend multiple educational sessions. Attrition rates for traditional interventions are frequently high due to competing demands for parents’ time. Under such constraints, an Internet-based intervention has the potential to modify determinants of childhood obesity while making judicious use of parents’ time. Theory-based interventions offer many advantages over atheoretical interventions, including reduced intervention dosage, increased likelihood of behavioral change, and efficient resource allocation. Social cognitive theory (SCT) is a robust theoretical framework for addressing childhood obesity. SCT is a behavior change model rooted in reciprocal determinism, a causal paradigm that states that human functioning is the product of a dynamic interplay of behavioral, personal, and environmental factors. Objectives: To evaluate the efficacy of the Enabling Mothers to Prevent Childhood Obesity Through Web-Based Education and Reciprocal Determinism (EMPOWER) program, an Internet-based, theory-driven intervention for preventing childhood overweight and obesity. The project goal is supported by two specific aims: (1) modification of four obesogenic protective factors related to childhood obesity (minutes engaged in physical activity, servings of fruits and vegetables consumed, servings of sugar-sweetened and sugar-free beverages consumed, and minutes engaged in screen time), and (2) reification of five maternal-mediated constructs of SCT (environment, expectations, emotional coping, self-control, and self-efficacy). Methods: We will recruit mothers with children ages 4 to 6 years from childcare centers and randomly assign them to either the theory-based (experimental) or knowledge-based (control) arm of the trial. Data for the intervention will be collected at three intervals: baseline (week 0), posttest (week 4), and follow-up (8 weeks). At each phase of data collection, we will collect from both groups (1) measures of the four obesogenic protective factors, and (2) summated SCT construct scores. Constructs will be measured by a psychometrically valid and reliable SCT-based instrument. Behaviors will be evaluated by a behavior log. We will use a repeated-measures one-between-, one-within-participants design to evaluate intervention results. Constructs will be modified through Web-based learning modules, online interactive worksheets, and mother–child home-based activities. Process evaluation will assess program fidelity. PMID:23611831

A study of education and KSAOs on career entry for product engineers: What employers really want

NASA Astrophysics Data System (ADS)

Thornburgh, James

The purpose of the study was to investigate the ways that employers of product engineers evaluate potential employees' job readiness, and which theories related to the education-work transaction are supported by practice. This study used a mixed methods approach and consisted of a state-wide survey (N=106) and local interviews (N=8). The results of the research indicate that attributes of both the Theory of Individual Differences and Credentialing Theory are present in the hiring practices of product engineers. Consistent with the Theory of Individual Differences, employers indicate they look for evidence of various job-related Knowledge, Skills, Abilities, and Other attributes (KSAOs) and they indicate they are willing to hire applicants who have less than a bachelor's degree. Consistent with Credentialing Theory, employers advertise a formal education minimum which represents only one way that individuals may learn to be an engineer. This study also confirmed prior research that most employers use primarily non-evidence based predictors to evaluate applicants. The primary initial screening predictors were experience, GPA, and major, while the primary finalist selection predictors were unstructured interviews, and applications, followed by structured interviews, job knowledge tests, and work sample test. Contrary to previous findings, this study did not find any major differences between what HR professionals, engineering managers, or other manager look for in terms of qualifications or what predictors they use when evaluating applicants for product engineer positions.

Predicting participation in ultrasound hip screening from message framing.

PubMed

Witting, Marjon; Boere-Boonekamp, Magda M; Fleuren, Margot A H; Sakkers, Ralph J B; Ijzerman, Maarten J

2012-01-01

The use of ultrasound (US) screening for developmental dysplasia of the hip (DDH) is an innovation in preventive child health care in the Netherlands. What is not known is whether parents will accept this screening method and will actually participate in it. It is widely known that health behaviors can be influenced by the framing of information. The objective of this study was to examine the influence of a gain- versus loss-framed brochure on parental participation in US screening for DDH. In total, 4150 parents of infants born between August 2007 and December 2008 received either a gain-framed or a loss-framed brochure. Parents could participate in the screening when their infant was 3 months old. The participation rate in the US screening was 74.3%. In contrast to the predictions of prospect theory, the results indicated that parents who had received the gain-framed message were more likely to participate in the screening compared to parents who had received the loss-framed message. This effect may be explained by the low risk perception of parents and by the possibility that the screening was perceived as a health-affirming behavior rather than an illness-detecting behavior. To increase participation rates, it is recommended that parents be informed about the positive aspects of partaking in screening for DDH.

Views of Somali women and men on the use of faith-based messages promoting breast and cervical cancer screening for Somali women: a focus-group study.

PubMed

Pratt, Rebekah; Mohamed, Sharif; Dirie, Wali; Ahmed, Nimo; VanKeulen, Michael; Ahmed, Huda; Raymond, Nancy; Okuyemi, Kola

2017-03-20

Screening rates for breast and cervical cancer for Muslim women in the United States are low, particularly for first-generation immigrants. Interpretations of the Muslim faith represent some of the barriers for breast and cervical cancer screening. Working to understand how faith influences breast and cervical screening for Somali women, and working with the community to identify and utilize faith-based assets for promoting screening, may lead to life-saving changes in screening behaviors. We partnered with an Imam to develop faith-based messages addressing the concerns of modesty and predetermination and promoting cancer testing and screening. A total of five focus groups were convened, with 34 Somali women (three groups) and 20 Somali men (two groups). Each focus group first discussed participant views of breast and cervical cancer screening in general and then viewed and discussed video clips of the Imam delivering the faith-based messages. Both Somali women and men had an overwhelmingly positive response to the faith-based messages promoting breast and cervical cancer screening. The faith-based messages appeared to reinforce the views of those who were already inclined to see screening positively, with participants describing increased confidence to engage in screening. For those who had reservations about screening, there was feedback that the faith-based messages had meaningfully influenced their views. Somali immigrant women and men found faith-based messages addressing topics of predestination and modesty and encouraging the use of screening and treatment to be both acceptable and influential. Faith can play an important role as an asset to promote breast and cervical cancer screening, and there may be substantial benefits to adding faith-based messaging to other interventions that focus on improving screening uptake. This may help to address health disparities for Somali women in this area.

Prostate-Specific Antigen (PSA)–Based Population Screening for Prostate Cancer: An Economic Analysis

PubMed Central

Tawfik, A

2015-01-01

Background The prostate-specific antigen (PSA) blood test has become widely used in Canada to test for prostate cancer (PC), the most common cancer among Canadian men. Data suggest that population-based PSA screening may not improve overall survival. Objectives This analysis aimed to review existing economic evaluations of population-based PSA screening, determine current spending on opportunistic PSA screening in Ontario, and estimate the cost of introducing a population-based PSA screening program in the province. Methods A systematic literature search was performed to identify economic evaluations of population-based PSA screening strategies published from 1998 to 2013. Studies were assessed for their methodological quality and applicability to the Ontario setting. An original cost analysis was also performed, using data from Ontario administrative sources and from the published literature. One-year costs were estimated for 4 strategies: no screening, current (opportunistic) screening of men aged 40 years and older, current (opportunistic) screening of men aged 50 to 74 years, and population-based screening of men aged 50 to 74 years. The analysis was conducted from the payer perspective. Results The literature review demonstrated that, overall, population-based PSA screening is costly and cost-ineffective but may be cost-effective in specific populations. Only 1 Canadian study, published 15 years ago, was identified. Approximately $119.2 million is being spent annually on PSA screening of men aged 40 years and older in Ontario, including close to $22 million to screen men younger than 50 and older than 74 years of age (i.e., outside the target age range for a population-based program). A population-based screening program in Ontario would cost approximately $149.4 million in the first year. Limitations Estimates were based on the synthesis of data from a variety of sources, requiring several assumptions and causing uncertainty in the results. For example, where Ontario-specific data were unavailable, data from the United States were used. Conclusions PSA screening is associated with significant costs to the health care system when the cost of the PSA test itself is considered in addition to the costs of diagnosis, staging, and treatment of screen-detected PCs. PMID:26366237

Probing dark energy with atom interferometry

NASA Astrophysics Data System (ADS)

Burrage, Clare; Copeland, Edmund J.; Hinds, E. A.

2015-03-01

Theories of dark energy require a screening mechanism to explain why the associated scalar fields do not mediate observable long range fifth forces. The archetype of this is the chameleon field. Here we show that individual atoms are too small to screen the chameleon field inside a large high-vacuum chamber, and therefore can detect the field with high sensitivity. We derive new limits on the chameleon parameters from existing experiments, and show that most of the remaining chameleon parameter space is readily accessible using atom interferometry.

Direct probe of the variability of Coulomb correlation in iron pnictide superconductors

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

Vilmercati, P.; Parks Cheney, C.; Bondino, F.

2012-01-01

We use core-valence-valence Auger spectra to probe the Coulomb repulsion between holes in the valence band of Fe pnictide superconductors. By comparing the two-hole final-state spectra to density functional theory calculations of the single-particle density of states, we extract a measure of the electron correlations that exist in these systems. Our results show that the Coulomb repulsion is highly screened and can definitively be considered as weak. We also find that there are differences between the 1111 and 122 families and even a small variation as a function of the doping x in Ba(Fe{sub 1-x}Co{sub x}){sub 2}As{sub 2}. We discussmore » how the values of the hole-hole Coulomb repulsion obtained from our study relate to the onsite Coulomb parameter U used in model and first-principles calculations based on dynamical mean field theory and establish an upper bound for its effective value. Our results impose stringent constraints on model-based phase diagrams that vary with the quantity U or U/W by restricting the latter to a rather small range of values.« less

Development and Implementation of a Smartphone Application to Promote Physical Activity and Reduce Screen-Time in Adolescent Boys

PubMed Central

Lubans, David R.; Smith, Jordan J.; Skinner, Geoff; Morgan, Philip J.

2014-01-01

Purpose: To describe the development and implementation of a smartphone application (app) designed to promote physical activity and reduce screen-time in adolescent boys considered “at-risk” of obesity. Methods: An app was developed to support the delivery of a face-to-face school-based obesity prevention program known as the “Active Teen Leaders Avoiding Screen-time” (ATLAS) program. ATLAS was guided by self-determination theory and social cognitive theory and evaluated using a cluster randomized controlled trial with 361 boys (12.7 ± 0.5 years) in 14 secondary schools. Following the completion of the study, participants in the intervention group completed a process evaluation questionnaire and focus groups were conducted with 42 students to explore their general perceptions of the ATLAS program and their experience with the smartphone app. Barriers and challenges encountered in the development, implementation, and evaluation of the app are also described. Results: Participation in the study was not contingent on ownership of a smartphone, but 70% of participants in the intervention group reported having access to a smartphone or tablet device. Focus group participants reported an enjoyment of the program, and felt that it had provided them with new skills, techniques, and routines for the future. However, their engagement with the smartphone app was limited, due to a variety of reasons. Barriers to the implementation and evaluation of the app included limited access to smartphone devices, technical problems with the push notifications, lack of access to usage data, and the challenges of maintaining participants’ interest in using the app. Conclusion: Although participants reported high levels of satisfaction with the ATLAS program in general, the smartphone app was not used extensively. Additional strategies and features may be needed to enhance engagement in adolescent boys. PMID:24904909

A psychometric investigation of the hypersexual disorder screening inventory among highly sexually active gay and bisexual men: an item response theory analysis.

PubMed

Parsons, Jeffrey T; Rendina, H Jonathon; Ventuneac, Ana; Cook, Karon F; Grov, Christian; Mustanski, Brian

2013-12-01

The Hypersexual Disorder Screening Inventory (HDSI) was designed as an instrument for the screening of hypersexuality by the American Psychiatric Association's taskforce for the fifth edition of the Diagnostic and Statistical Manual of Mental Disorders. Our study sought to conduct a psychometric analysis of the HDSI, including an investigation of its underlying structure and reliability utilizing item response theory (IRT) modeling, and an examination of its polythetic scoring criteria in comparison to a standard dimensionally based cutoff score. We examined a diverse group of 202 highly sexually active gay and bisexual men in New York City. We conducted psychometric analyses of the HDSI, including both confirmatory factor analysis of its structure and IRT analysis of the item and scale reliabilities. We utilized the HDSI. The HDSI adequately fit a single-factor solution, although there was evidence that two of the items may measure a second factor that taps into sex as a form of coping. The scale showed evidence of strong reliability across much of the continuum of hypersexuality, and results suggested that, in addition to the proposed polythetic scoring criteria, a cutoff score of 20 on the severity index might be used for preliminary classification of HD. The HDSI was found to be highly reliable, and results suggested that a unidimensional, quantitative conception of hypersexuality with a clinically relevant cutoff score may be more appropriate than a qualitative syndrome comprised of multiple distinct clusters of problems. However, we also found preliminary evidence that three clusters of symptoms may constitute an HD syndrome as opposed to the two clusters initially proposed. Future research is needed to determine which of these issues are characteristic of the hypersexuality and HD constructs themselves and which are more likely to be methodological artifacts of the HDSI. © 2013 International Society for Sexual Medicine.

3D mosquito screens to create window double screen traps for mosquito control.

PubMed

Khattab, Ayman; Jylhä, Kaisa; Hakala, Tomi; Aalto, Mikko; Malima, Robert; Kisinza, William; Honkala, Markku; Nousiainen, Pertti; Meri, Seppo

2017-08-29

Mosquitoes are vectors for many diseases such as malaria. Insecticide-treated bed nets and indoor residual spraying of insecticides are the principal malaria vector control tools used to prevent malaria in the tropics. Other interventions aim at reducing man-vector contact. For example, house screening provides additive or synergistic effects to other implemented measures. We used commercial screen materials made of polyester, polyethylene or polypropylene to design novel mosquito screens that provide remarkable additional benefits to those commonly used in house screening. The novel design is based on a double screen setup made of a screen with 3D geometric structures parallel to a commercial mosquito screen creating a trap between the two screens. Owing to the design of the 3D screen, mosquitoes can penetrate the 3D screen from one side but cannot return through the other side, making it a unidirectional mosquito screen. Therefore, the mosquitoes are trapped inside the double screen system. The permissiveness of both sides of the 3D screens for mosquitoes to pass through was tested in a wind tunnel using the insectary strain of Anopheles stephensi. Among twenty-five tested 3D screen designs, three designs from the cone, prism, or cylinder design groups were the most efficient in acting as unidirectional mosquito screens. The three cone-, prism-, and cylinder-based screens allowed, on average, 92, 75 and 64% of Anopheles stephensi mosquitoes released into the wind tunnel to penetrate the permissive side and 0, 0 and 6% of mosquitoes to escape through the non-permissive side, respectively. A cone-based 3D screen fulfilled the study objective. It allowed capturing 92% of mosquitoes within the double screen setup inside the wind tunnel and blocked 100% from escaping. Thus, the cone-based screen effectively acted as a unidirectional mosquito screen. This 3D screen-based trap design could therefore be used in house screening as a means of avoiding infective bites and reducing mosquito population size.

Magnetocrystalline anisotropy in cobalt based magnets: a choice of correlation parameters and the relativistic effects

DOE PAGES

Nguyen, Manh Cuong; Yao, Yongxin; Wang, Cai-Zhuang; ...

2018-05-16

The dependence of the magnetocrystalline anisotropy energy (MAE) in MCo 5 (M = Y, La, Ce, Gd) and CoPt on the Coulomb correlations and strength of spin orbit (SO) interaction within the GGA + U scheme is investigated. A range of parameters suitable for the satisfactory description of key magnetic properties is determined. We show that for a large variation of SO interaction the MAE in these materials can be well described by the traditional second order perturbation theory. We also show that in these materials the MAE can be both proportional and negatively proportional to the orbital moment anisotropymore » (OMA) of Co atoms. Dependence of relativistic effects on Coulomb correlations, applicability of the second order perturbation theory for the description of MAE, and effective screening of the SO interaction in these systems are discussed using a generalized virial theorem. Finally, such determined sets of parameters of Coulomb correlations can be used in much needed large scale atomistic simulations.« less

Phonon bottleneck identification in disordered nanoporous materials

NASA Astrophysics Data System (ADS)

Romano, Giuseppe; Grossman, Jeffrey C.

2017-09-01

Nanoporous materials are a promising platform for thermoelectrics in that they offer high thermal conductivity tunability while preserving good electrical properties, a crucial requirement for high-efficiency thermal energy conversion. Understanding the impact of the pore arrangement on thermal transport is pivotal to engineering realistic materials, where pore disorder is unavoidable. Although there has been considerable progress in modeling thermal size effects in nanostructures, it has remained a challenge to screen such materials over a large phase space due to the slow simulation time required for accurate results. We use density functional theory in connection with the Boltzmann transport equation to perform calculations of thermal conductivity in disordered porous materials. By leveraging graph theory and regressive analysis, we identify the set of pores representing the phonon bottleneck and obtain a descriptor for thermal transport, based on the sum of the pore-pore distances between such pores. This approach provide a simple tool to estimate phonon suppression in realistic porous materials for thermoelectric applications and enhance our understanding of heat transport in disordered materials.

Magnetocrystalline anisotropy in cobalt based magnets: a choice of correlation parameters and the relativistic effects

NASA Astrophysics Data System (ADS)

Nguyen, Manh Cuong; Yao, Yongxin; Wang, Cai-Zhuang; Ho, Kai-Ming; Antropov, Vladimir P.

2018-05-01

The dependence of the magnetocrystalline anisotropy energy (MAE) in MCo5 (M  =  Y, La, Ce, Gd) and CoPt on the Coulomb correlations and strength of spin orbit (SO) interaction within the GGA  +  U scheme is investigated. A range of parameters suitable for the satisfactory description of key magnetic properties is determined. We show that for a large variation of SO interaction the MAE in these materials can be well described by the traditional second order perturbation theory. We also show that in these materials the MAE can be both proportional and negatively proportional to the orbital moment anisotropy (OMA) of Co atoms. Dependence of relativistic effects on Coulomb correlations, applicability of the second order perturbation theory for the description of MAE, and effective screening of the SO interaction in these systems are discussed using a generalized virial theorem. Such determined sets of parameters of Coulomb correlations can be used in much needed large scale atomistic simulations.

Magnetocrystalline anisotropy in cobalt based magnets: a choice of correlation parameters and the relativistic effects

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

Nguyen, Manh Cuong; Yao, Yongxin; Wang, Cai-Zhuang

The dependence of the magnetocrystalline anisotropy energy (MAE) in MCo 5 (M = Y, La, Ce, Gd) and CoPt on the Coulomb correlations and strength of spin orbit (SO) interaction within the GGA + U scheme is investigated. A range of parameters suitable for the satisfactory description of key magnetic properties is determined. We show that for a large variation of SO interaction the MAE in these materials can be well described by the traditional second order perturbation theory. We also show that in these materials the MAE can be both proportional and negatively proportional to the orbital moment anisotropymore » (OMA) of Co atoms. Dependence of relativistic effects on Coulomb correlations, applicability of the second order perturbation theory for the description of MAE, and effective screening of the SO interaction in these systems are discussed using a generalized virial theorem. Finally, such determined sets of parameters of Coulomb correlations can be used in much needed large scale atomistic simulations.« less

Autism and urinary exogenous neuropeptides: development of an on-line SPE-HPLC-tandem mass spectrometry method to test the opioid excess theory.

PubMed

Dettmer, K; Hanna, D; Whetstone, P; Hansen, R; Hammock, B D

2007-08-01

Autism is a complex neurodevelopmental disorder with unknown etiology. One hypothesis regarding etiology in autism is the "opioid peptide excess" theory that postulates that excessive amounts of exogenous opioid-like peptides derived from dietary proteins are detectable in urine and that these compounds may be pathophysiologically important in autism. A selective LC-MS/MS method was developed to analyze gliadinomorphin, beta-casomorphin, deltorphin 1, and deltorphin 2 in urine. The method is based on on-line SPE extraction of the neuropeptides from urine, column switching, and subsequent HPLC analysis. A limit of detection of 0.25 ng/mL was achieved for all analytes. Analyte recovery rates from urine ranged between 78% and 94%, with relative standard deviations of 0.2-6.8%. The method was used to screen 69 urine samples from children with and without autism spectrum disorders for the occurrence of neuropeptides. The target neuropeptides were not detected above the detection limit in either sample set.

The Shared Decision Making Frontier: a Feasibility and Usability Study for Managing Non-Critical Chronic Illness by Combining Behavioural & Decision Theory with Online Technology.

PubMed

Russell, Amina; Van Woensel, William; Abidi, Samina Raza

2015-01-01

The objective of this study is to determine if shared decisions for managing non-critical chronic illness, made through an online biomedical technology intervention, us feasible and usable. The technology intervention incorporates behavioural and decision theories to increase patient engagement, and ultimately long term adherence to health behaviour change. We devised the iheart web intervention as a "proof of concept" in five phases. The implementation incorporates the Vaadin web application framework, Drools, EclipseLink and a MySQL database. Two-thirds of the study participants favoured the technology intervention, based on Likert-scale questions from a post-study questionnaire. Qualitative analysis of think aloud feedback, video screen captures and open-ended questions from the post-study questionnaire uncovered six main areas or themes for improvement. We conclude that online shared decisions for managing a non-critical chronic illness are feasible and usable through the iheart web intervention.

Statistical mechanics of light elements at high pressure. VI - Liquid-state calculations with Thomas-Fermi-Dirac theory

NASA Technical Reports Server (NTRS)

Macfarlane, J. J.

1984-01-01

A model free energy is developed for hydrogen-helium mixtures based on solid-state Thomas-Fermi-Dirac calculations at pressures relevant to the interiors of giant planets. Using a model potential similar to that for a two-component plasma, effective charges for the nuclei (which are in general smaller than the actual charges because of screening effects) are parameterized, being constrained by calculations at a number of densities, compositions, and lattice structures. These model potentials are then used to compute the equilibrium properties of H-He fluids using a charged hard-sphere model. The results find critical temperatures of about 0 K, 500 K, and 1500 K, for pressures of 10, 100, and 1000 Mbar, respectively. These phase separation temperatures are considerably lower (approximately 6,000-10,000 K) than those found from calculations using free electron perturbation theory, and suggest that H-He solutions should be stable against phase separation in the metallic zones of Jupiter and Saturn.

Charge ordering in ionic fluids mediate repulsive surface interactions

NASA Astrophysics Data System (ADS)

Dasbiswas, Kinjal; Ludwig, Nicholas B.; Zhang, Hao; Talapin, Dmitri; Vaikuntanathan, Suri

Recent experiments on ionic fluids, such as surface force measurements in organic ionic liquids and the observation of colloidal stability in inorganic molten salts, suggest the presence of long-ranged repulsive forces. These cannot be explained within the classical Debye-Hückel theory for dilute electrolytes. We argue that such repulsive interactions can arise from long-range (several nm) charge density oscillations induced by a surface that preferentially binds one of the ionic species in an ionic fluid. We present a continuum theory that accounts for such charge layering based on a frustrated Ising model that incorporates both long-range Coulombic and short-range steric interactions. The mean-field analytic treatment qualitatively matches results from molecular simulations. A careful analysis of the ionic correlation functions arising from such charge ordering may also explain the long electrostatic screening lengths observed in various ionic fluids and their non-monotonic dependence on the electrolyte concentration. We acknowledge the University of Chicago for support.

A grounded theory of positive youth development through sport based on results from a qualitative meta-study

PubMed Central

Holt, Nicholas L.; Neely, Kacey C.; Slater, Linda G.; Camiré, Martin; Côté, Jean; Fraser-Thomas, Jessica; MacDonald, Dany; Strachan, Leisha; Tamminen, Katherine A.

2017-01-01

ABSTRACT The overall purpose of this study was to create a model of positive youth development (PYD) through sport grounded in the extant qualitative literature. More specifically, the first objective was to review and evaluate qualitative studies of PYD in sport. The second objective was to analyze and synthesize findings from these studies. Following record identification and screening, 63 articles were retained for analysis. Meta-method analysis revealed strengths of studies were the use of multiple data collection and validity techniques, which produced high-quality data. Weaknesses were limited use of ‘named’ methodologies and inadequate reporting of sampling procedures. Philosophical perspectives were rarely reported, and theory was used sparingly. Results of an inductive meta-data analysis produced three categories: PYD climate (adult relationships, peer relationships, and parental involvement), life skills program focus (life skill building activities and transfer activities), and PYD outcomes (in personal, social, and physical domains). A model that distinguishes between implicit and explicit processes to PYD is presented. PMID:27695511

UVPROM dosimetry, microdosimetry and applications to SEU and extreme value theory

NASA Astrophysics Data System (ADS)

Scheick, Leif Zebediah

A new method is described for characterizing a device in terms of the statistical distribution of first failures. The method is based on the erasure of a commercial Ultra- Violet erasable Programmable Read Only Memory (UVPROM). The method of readout would be used on a spacecraft or in other restrictive radiation environments. The measurement of the charge remaining on the floating gate is used to determine absorbed dose. The method of determining dose does not require the detector to be destroyed or erased nor does it effect the ability for taking further measurements. This is compared to extreme value theory applied to the statistical distributions that apply to this device. This technique predicts the threshold of Single Event Effects (SEE), like anomalous changes in erasure time in programmable devices due to high microdose energy-deposition events. This technique also allows for advanced non-destructive, screening of a single microelectronic devices for predictable response in a stressful, i.e. radiation, environments.

Theory and Practice in the Design of Physician Payment Incentives

PubMed Central

Robinson, James C.

2001-01-01

Combining the economic literature on principal-agent relationships with examples of marketplace innovations allows analysis of the evolution of methods for paying physicians. Agency theory and the economic principles of performance-based compensation are applied in the context of imperfect information, risk aversion, multiple interrelated tasks, and team production efficiencies. Fee-for-service and capitation are flawed methods of motivating physicians to achieve specific goals. Payment innovations that blend elements of fee-for-service, capitation, and case rates can preserve the advantages and attenuate the disadvantages of each. These innovations include capitation with fee-for-service carve-outs, department budgets with individual fee-for-service or “contact” capitation, and case rates for defined episodes of illness. The context within which payment incentives are embedded, includes such nonprice mechanisms as screening and monitoring and such organizational relationships as employment and ownership. The analysis has implications for health services research and public policy with respect to physician payment incentives. PMID:11439463

Views of Dental Providers on Primary Care Coordination at Chairside: A Pilot Study.

PubMed

Northridge, Mary E; Birenz, Shirley; Gomes, Danni M; Golembeski, Cynthia A; Greenblatt, Ariel Port; Shelley, Donna; Russell, Stefanie L

2016-06-01

There is a need for research to facilitate the widespread implementation, dissemination and sustained utilization of evidence-based primary care screening, monitoring and care coordination guidelines, thereby increasing the impact of dental hygienists' actions on patients' oral and general health. The aims of this formative study are to explore dental hygienists' and dentists' perspectives regarding the integration of primary care activities into routine dental care, and assess the needs of dental hygienists and dentists regarding primary care coordination activities and use of information technology to obtain clinical information at chairside. This qualitative study recruited 10 dental hygienists and 6 dentists from 10 New York City area dental offices with diverse patient mixes and volumes. A New York University faculty dental hygienist conducted semi-structured, in-depth interviews, which were digitally recorded and transcribed verbatim. Data analysis consisted of multilevel coding based on the Consolidated Framework for Implementation Research, resulting in emergent themes with accompanying categories. The dental hygienists and dentists interviewed as part of this study do not use evidence-based guidelines to screen their patients for primary care sensitive conditions. Overwhelmingly, dental providers believe that tobacco use and poor diet contribute to oral disease, and report using electronic devices at chairside to obtain web-based health information. Dental hygienists are well positioned to help facilitate greater integration of oral and general health care. Challenges include lack of evidence-based knowledge, coordination between dental hygienists and dentists, and systems-level support, with opportunities for improvement based upon a theory-driven framework. Copyright © 2016 The American Dental Hygienists’ Association.

Views of Dental Providers on Primary Care Coordination at Chairside: A Pilot Study

PubMed Central

Northridge, Mary E.; Birenz, Shirley; Gomes, Danni; Golembeski, Cynthia A.; Greenblatt, Ariel Port; Shelley, Donna; Russell, Stefanie L.

2016-01-01

Purpose There is a need for research to facilitate the widespread implementation, dissemination, and sustained utilization of evidence-based primary care screening, monitoring, and care coordination guidelines, thereby increasing the impact of dental hygienists’ actions on patients’ oral and general health. The aims of this formative study are to: (1) explore dental hygienists’ and dentists’ perspectives regarding the integration of primary care activities into routine dental care; and (2) assess the needs of dental hygienists and dentists regarding primary care coordination activities and use of information technology to obtain clinical information at chairside. Methods This qualitative study recruited ten hygienists and six dentists from ten New York City area dental offices with diverse patient mixes and volumes. A New York University faculty hygienist conducted semi-structured, in-depth interviews, which were digitally recorded and transcribed verbatim. Data analysis consisted of multilevel coding based on the Consolidated Framework for Implementation Research, resulting in emergent themes with accompanying categories. Results The dental hygienists and dentists interviewed as part of this study fail to use evidence-based guidelines to screen their patients for primary care sensitive conditions. Overwhelmingly, dental providers believe that tobacco use and poor diet contribute to oral disease, and report using electronic devices at chairside to obtain web-based health information. Conclusion Dental hygienists are well positioned to help facilitate greater integration of oral and general health care. Challenges include lack of evidence-based knowledge, coordination between dental hygienists and dentists, and systems-level support, with opportunities for improvement based upon a theory-driven framework. PMID:27340183

Breast cancer screening in an era of personalized regimens: a conceptual model and National Cancer Institute initiative for risk-based and preference-based approaches at a population level.

PubMed

Onega, Tracy; Beaber, Elisabeth F; Sprague, Brian L; Barlow, William E; Haas, Jennifer S; Tosteson, Anna N A; D Schnall, Mitchell; Armstrong, Katrina; Schapira, Marilyn M; Geller, Berta; Weaver, Donald L; Conant, Emily F

2014-10-01

Breast cancer screening holds a prominent place in public health, health care delivery, policy, and women's health care decisions. Several factors are driving shifts in how population-based breast cancer screening is approached, including advanced imaging technologies, health system performance measures, health care reform, concern for "overdiagnosis," and improved understanding of risk. Maximizing benefits while minimizing the harms of screening requires moving from a "1-size-fits-all" guideline paradigm to more personalized strategies. A refined conceptual model for breast cancer screening is needed to align women's risks and preferences with screening regimens. A conceptual model of personalized breast cancer screening is presented herein that emphasizes key domains and transitions throughout the screening process, as well as multilevel perspectives. The key domains of screening awareness, detection, diagnosis, and treatment and survivorship are conceptualized to function at the level of the patient, provider, facility, health care system, and population/policy arena. Personalized breast cancer screening can be assessed across these domains with both process and outcome measures. Identifying, evaluating, and monitoring process measures in screening is a focus of a National Cancer Institute initiative entitled PROSPR (Population-based Research Optimizing Screening through Personalized Regimens), which will provide generalizable evidence for a risk-based model of breast cancer screening, The model presented builds on prior breast cancer screening models and may serve to identify new measures to optimize benefits-to-harms tradeoffs in population-based screening, which is a timely goal in the era of health care reform. © 2014 American Cancer Society.

Cost-effectiveness of organized versus opportunistic cervical cytology screening in Hong Kong.

PubMed

Kim, Jane J; Leung, Gabriel M; Woo, Pauline P S; Goldie, Sue J

2004-06-01

To assess the cost-effectiveness of alternative cervical cancer screening strategies to inform the design and implementation of a government-sponsored population-based screening programme in Hong Kong. Cost-effectiveness analysis using a computer-based model of cervical carcinogenesis was performed. Strategies included no screening, opportunistic screening (status quo), organized screening using either conventional or liquid-based cytology conducted at different frequencies. The main outcome measures were cancer incidence reduction, years of life saved (YLS), lifetime costs and incremental cost-effectiveness ratios. Data were from local hospitals and laboratories, clinical trials, prospective studies and other published literature. Compared with no screening, a simulation of the current situation of opportunistic screening using cervical cytology produced a nearly 40 per cent reduction in the lifetime risk of cervical cancer. However, with organized screening every 3, 4 and 5 years, corresponding reductions with conventional (and liquid-based) cytology were 90.4 (92.9), 86.8 (90.2) and 83.2 per cent (87.3 per cent) compared with no screening. For all cytology-based screening strategies, opportunistic screening was more costly and less effective than an organized programme of screening every 3, 4 and 5 years. Every 3-, 4- and 5-year screening cost $12,300, $7100 and $800 per YLS, each compared with the next best alternative. Compared with the status quo of opportunistic screening, adopting a policy of organized, mass cervical screening in Hong Kong can substantially increase benefits and reduce costs.

Scaling behaviour of Fisher and Shannon entropies for the exponential-cosine screened coulomb potential

NASA Astrophysics Data System (ADS)

Abdelmonem, M. S.; Abdel-Hady, Afaf; Nasser, I.

2017-07-01

The scaling laws are given for the entropies in the information theory, including the Shannon's entropy, its power, the Fisher's information and the Fisher-Shannon product, using the exponential-cosine screened Coulomb potential. The scaling laws are specified, in the r-space, as a function of |μ - μc, nℓ|, where μ is the screening parameter and μc, nℓ its critical value for the specific quantum numbers n and ℓ. Scaling laws for other physical quantities, such as energy eigenvalues, the moments, static polarisability, transition probabilities, etc. are also given. Some of these are reported for the first time. The outcome is compared with the available literatures' results.

Using intervention mapping for the development of a targeted secure web-based outreach strategy named SafeFriend, for Chlamydia trachomatis testing in young people at risk

PubMed Central

2013-01-01

Background Many young people at high risk for Chlamydia trachomatis (Ct) are not reached by current sexual health care systems, such as general practitioners and public sexual health care centres (sexually transmitted infection clinics).Ct is the most frequently diagnosed bacterial sexually transmitted infection (STI) among sexually active people and in particular young heterosexuals. Innovative screening strategies are needed to interrupt the transmission of Ct among young people and connect the hidden cases to care. Methods Intervention Mapping (IM), a systematic approach to develop theory- and evidence-based interventions, was used to develop a strategy to target Ct testing towards young people who are currently hidden to care in The Netherlands. Both clinical users (i.e. sexual health care nurses) and public users (i.e., young people at risk for Ct) were closely involved in the IM process. A needs assessment study was carried out using semi-structured interviews among users (N = 21), a literature search and by taking lessons learned from existing screening programmes. Theoretical methods and practical applications to reach high risk young people and influence testing were selected and translated into specific programme components. Results The IM approach resulted in the development of a secure and web-based outreach Ct screening strategy, named SafeFriend. It is developed to target groups of high-risk young people who are currently hidden to care. Key methods include web-based Respondent Driven Sampling, starting from young Ct positive sexual health care centre clients, to reach and motivate peers (i.e., sex partners and friends) to get tested for Ct. Testing and the motivation of peers were proposed as the desired behavioural outcomes and the Precaution Adoption Process Model was chosen as theoretical framework. End users, i.e., young people and sexual health care nurses were interviewed and included in the development process to increase the success of implementation. Conclusions IM proved useful to develop an intervention for targeted Ct testing among young people. We believe this to be the first web-based outreach screening strategy which combines chain referral sampling with the delivery of targeted Ct testing to high risk young people within their sexual and social networks. PMID:24148656

Using intervention mapping for the development of a targeted secure web-based outreach strategy named SafeFriend, for Chlamydia trachomatis testing in young people at risk.

PubMed

Theunissen, Kevin A T M; Hoebe, Christian J P A; Crutzen, Rik; Kara-Zaïtri, Chakib; de Vries, Nanne K; van Bergen, Jan E A M; van der Sande, Marianne A B; Dukers-Muijrers, Nicole H T M

2013-10-22

Many young people at high risk for Chlamydia trachomatis (Ct) are not reached by current sexual health care systems, such as general practitioners and public sexual health care centres (sexually transmitted infection clinics).Ct is the most frequently diagnosed bacterial sexually transmitted infection (STI) among sexually active people and in particular young heterosexuals. Innovative screening strategies are needed to interrupt the transmission of Ct among young people and connect the hidden cases to care. Intervention Mapping (IM), a systematic approach to develop theory- and evidence-based interventions, was used to develop a strategy to target Ct testing towards young people who are currently hidden to care in The Netherlands. Both clinical users (i.e. sexual health care nurses) and public users (i.e., young people at risk for Ct) were closely involved in the IM process. A needs assessment study was carried out using semi-structured interviews among users (N = 21), a literature search and by taking lessons learned from existing screening programmes. Theoretical methods and practical applications to reach high risk young people and influence testing were selected and translated into specific programme components. The IM approach resulted in the development of a secure and web-based outreach Ct screening strategy, named SafeFriend. It is developed to target groups of high-risk young people who are currently hidden to care. Key methods include web-based Respondent Driven Sampling, starting from young Ct positive sexual health care centre clients, to reach and motivate peers (i.e., sex partners and friends) to get tested for Ct. Testing and the motivation of peers were proposed as the desired behavioural outcomes and the Precaution Adoption Process Model was chosen as theoretical framework. End users, i.e., young people and sexual health care nurses were interviewed and included in the development process to increase the success of implementation. IM proved useful to develop an intervention for targeted Ct testing among young people. We believe this to be the first web-based outreach screening strategy which combines chain referral sampling with the delivery of targeted Ct testing to high risk young people within their sexual and social networks.

SnO as a potential oxide thermoelectric candidate

DOE PAGES

Miller, Samuel A.; Gorai, Prashun; Aydemir, Umut; ...

2017-08-08

Here we search for new thermoelectric materials, high-throughput calculations using a combination of semiempirical models and first principles density functional theory present a path to screen large numbers of compounds for the most promising candidates.

Web-based screening and brief intervention for poly-drug use among teenagers: study protocol of a multicentre two-arm randomized controlled trial.

PubMed

Arnaud, Nicolas; Bröning, Sonja; Drechsel, Magdalena; Thomasius, Rainer; Baldus, Christiane

2012-09-26

Mid to late adolescence is characterised by a vulnerability to problematic substance use since the consumption of alcohol and illicit drugs is frequently initiated and increased in this life period. While the detrimental long- and short-term effects of problematic consumption patterns in adolescence pose a major public health concern, current prevention programs targeting alcohol- and other substance-using adolescents are scarce. The study described in this protocol will test the effectiveness of a web-based brief intervention aimed at reducing problematic alcohol use and promoting abstinence from illegal drugs in adolescents with risky substance use aged 16 to 18 years old in four EU-countries. To determine the effectiveness of our web-BI, we apply a two-arm randomized controlled trial (RCT) study design, with baseline assessment at study entry and a three month follow-up assessment. Adolescents aged 16 to 18 years from Belgium, the Czech Republic, Germany, and Sweden will be randomly assigned to either the fully electronically delivered brief intervention group (N = 400) or an assessment only control group (N = 400) depending on their screening for risky substance use (using the CRAFFT). Recruitment, informed consent, randomization, intervention and follow-up will be implemented online. Primary outcomes are reductions in frequency and quantity of use of alcohol and drugs other than alcohol over a 30 day period, as well as consumption per typical occasion. Secondary outcomes concern changes in substance use related cognitions including the constructs of the Theory of Planned Behaviour, implementation intentions, and stages of change. Moreover the study addresses a number of moderator variables, including age of first use, general psychopathology and quality of parent-child relationship. The trial is expected to contribute to the growing literature on theory- and web-based brief interventions for adolescents. We will explore the potential of using web-based technologies as means of delivering preventive interventions. In doing so we are among the first to target the relevant group of young poly-drug users in Europe. Current Controlled Trials ISRCTN95538913.

Failures of explaining away and screening off in described versus experienced causal learning scenarios.

PubMed

Rehder, Bob; Waldmann, Michael R

2017-02-01

Causal Bayes nets capture many aspects of causal thinking that set them apart from purely associative reasoning. However, some central properties of this normative theory routinely violated. In tasks requiring an understanding of explaining away and screening off, subjects often deviate from these principles and manifest the operation of an associative bias that we refer to as the rich-get-richer principle. This research focuses on these two failures comparing tasks in which causal scenarios are merely described (via verbal statements of the causal relations) versus experienced (via samples of data that manifest the intervariable correlations implied by the causal relations). Our key finding is that we obtained stronger deviations from normative predictions in the described conditions that highlight the instructed causal model compared to those that presented data. This counterintuitive finding indicate that a theory of causal reasoning and learning needs to integrate normative principles with biases people hold about causal relations.

Using intervention mapping to develop a breast and cervical cancer screening program for Hispanic farmworkers: Cultivando La Salud.

PubMed

Fernández, Maria E; Gonzales, Alicia; Tortolero-Luna, Guillermo; Partida, Sylvia; Bartholomew, L Kay

2005-10-01

This article describes the development of the Cultivando La Salud program, an intervention to increase breast and cervical cancer screening for Hispanic farmworker women. Processes and findings of intervention mapping (IM), a planning process for development of theory and evidence-informed program are discussed. The six IM steps are presented: needs assessment, preparation of planning matrices, election of theoretic methods and practical strategies, program design, implementation planning, and evaluation. The article also describes how qualitative and quantitative findings informed intervention development. IM helped ensure that theory and evidence guided (a) the identification of behavioral and environmental factors related to a target health problem and (b) the selection of the most appropriate methods and strategies to address the identified determinants. IM also guided the development of program materials and implementation by lay health workers. Also reported are findings of the pilot study and effectiveness trial.

Breast Cancer Screening in the Precision Medicine Era: Risk-Based Screening in a Population-Based Trial.

PubMed

Shieh, Yiwey; Eklund, Martin; Madlensky, Lisa; Sawyer, Sarah D; Thompson, Carlie K; Stover Fiscalini, Allison; Ziv, Elad; Van't Veer, Laura J; Esserman, Laura J; Tice, Jeffrey A

2017-01-01

Ongoing controversy over the optimal approach to breast cancer screening has led to discordant professional society recommendations, particularly in women age 40 to 49 years. One potential solution is risk-based screening, where decisions around the starting age, stopping age, frequency, and modality of screening are based on individual risk to maximize the early detection of aggressive cancers and minimize the harms of screening through optimal resource utilization. We present a novel approach to risk-based screening that integrates clinical risk factors, breast density, a polygenic risk score representing the cumulative effects of genetic variants, and sequencing for moderate- and high-penetrance germline mutations. We demonstrate how thresholds of absolute risk estimates generated by our prediction tools can be used to stratify women into different screening strategies (biennial mammography, annual mammography, annual mammography with adjunctive magnetic resonance imaging, defer screening at this time) while informing the starting age of screening for women age 40 to 49 years. Our risk thresholds and corresponding screening strategies are based on current evidence but need to be tested in clinical trials. The Women Informed to Screen Depending On Measures of risk (WISDOM) Study, a pragmatic, preference-tolerant randomized controlled trial of annual vs personalized screening, will study our proposed approach. WISDOM will evaluate the efficacy, safety, and acceptability of risk-based screening beginning in the fall of 2016. The adaptive design of this trial allows continued refinement of our risk thresholds as the trial progresses, and we discuss areas where we anticipate emerging evidence will impact our approach. © The Author 2017. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

Modelling the Costs and Effects of Selective and Universal Hospital Admission Screening for Methicillin-Resistant Staphylococcus aureus

PubMed Central

Hubben, Gijs; Bootsma, Martin; Luteijn, Michiel; Glynn, Diarmuid; Bishai, David

2011-01-01

Background Screening at hospital admission for carriage of methicillin-resistant Staphylococcus aureus (MRSA) has been proposed as a strategy to reduce nosocomial infections. The objective of this study was to determine the long-term costs and health benefits of selective and universal screening for MRSA at hospital admission, using both PCR-based and chromogenic media-based tests in various settings. Methodology/Principal Findings A simulation model of MRSA transmission was used to determine costs and effects over 15 years from a US healthcare perspective. We compared admission screening together with isolation of identified carriers against a baseline policy without screening or isolation. Strategies included selective screening of high risk patients or universal admission screening, with PCR-based or chromogenic media-based tests, in medium (5%) or high nosocomial prevalence (15%) settings. The costs of screening and isolation per averted MRSA infection were lowest using selective chromogenic-based screening in high and medium prevalence settings, at $4,100 and $10,300, respectively. Replacing the chromogenic-based test with a PCR-based test costs $13,000 and $36,200 per additional infection averted, and subsequent extension to universal screening with PCR would cost $131,000 and $232,700 per additional infection averted, in high and medium prevalence settings respectively. Assuming $17,645 benefit per infection averted, the most cost-saving strategies in high and medium prevalence settings were selective screening with PCR and selective screening with chromogenic, respectively. Conclusions/Significance Admission screening costs $4,100–$21,200 per infection averted, depending on strategy and setting. Including financial benefits from averted infections, screening could well be cost saving. PMID:21483492

An update on the use of C. elegans for preclinical drug discovery: screening and identifying anti-infective drugs.

PubMed

Kim, Wooseong; Hendricks, Gabriel Lambert; Lee, Kiho; Mylonakis, Eleftherios

2017-06-01

The emergence of antibiotic-resistant and -tolerant bacteria is a major threat to human health. Although efforts for drug discovery are ongoing, conventional bacteria-centered screening strategies have thus far failed to yield new classes of effective antibiotics. Therefore, new paradigms for discovering novel antibiotics are of critical importance. Caenorhabditis elegans, a model organism used for in vivo, offers a promising solution for identification of anti-infective compounds. Areas covered: This review examines the advantages of C. elegans-based high-throughput screening over conventional, bacteria-centered in vitro screens. It discusses major anti-infective compounds identified from large-scale C. elegans-based screens and presents the first clinically-approved drugs, then known bioactive compounds, and finally novel small molecules. Expert opinion: There are clear advantages of using a C. elegans-infection based screening method. A C. elegans-based screen produces an enriched pool of non-toxic, efficacious, potential anti-infectives, covering: conventional antimicrobial agents, immunomodulators, and anti-virulence agents. Although C. elegans-based screens do not denote the mode of action of hit compounds, this can be elucidated in secondary studies by comparing the results to target-based screens, or conducting subsequent target-based screens, including the genetic knock-down of host or bacterial genes.

A web-based platform for virtual screening.

PubMed

Watson, Paul; Verdonk, Marcel; Hartshorn, Michael J

2003-09-01

A fully integrated, web-based, virtual screening platform has been developed to allow rapid virtual screening of large numbers of compounds. ORACLE is used to store information at all stages of the process. The system includes a large database of historical compounds from high throughput screenings (HTS) chemical suppliers, ATLAS, containing over 3.1 million unique compounds with their associated physiochemical properties (ClogP, MW, etc.). The database can be screened using a web-based interface to produce compound subsets for virtual screening or virtual library (VL) enumeration. In order to carry out the latter task within ORACLE a reaction data cartridge has been developed. Virtual libraries can be enumerated rapidly using the web-based interface to the cartridge. The compound subsets can be seamlessly submitted for virtual screening experiments, and the results can be viewed via another web-based interface allowing ad hoc querying of the virtual screening data stored in ORACLE.

HPV vaccination impact on a cervical cancer screening program: methods of the FASTER-Tlalpan Study in Mexico.

PubMed

Salmerón, Jorge; Torres-Ibarra, Leticia; Bosch, F Xavier; Cuzick, Jack; Lörincz, Attila; Wheeler, Cosette M; Castle, Philip E; Robles, Claudia; Lazcano-Ponce, Eduardo

2016-04-01

To outline the design of a clinical trial to evaluate the impact of HPV vaccination as part of a hrHPV-based primary screening program to extend screening intervals. A total of 18,000 women aged 25-45 years, attending the regular cervical cancer-screening program in primary health care services in Tlalpan, Mexico City, will be invited to the study. Eligible participants will be assigned to one of three comparison groups: 1) HPV16/18 vaccine and hrHPV-based screening; 2) HPV6/11/16/18 vaccine and hrHPV-based screening; 3) Control group who will receive only hrHPV-based screening. Strict surveillance of hrHPV persistent infection and occurrence of precancerous lesions will be conducted to estimate safety profiles at different screening intervals; participants will undergo diagnosis confirmation and treatment as necessary. The FASTER-Tlalpan Study will provide insights into new approaches of cervical cancer prevention programs. It will offer valuable information on potential benefits of combining HPV vaccination and hrHPV-based screening to safety extend screening intervals.

Viscosity of Xenon Examined in Microgravity

NASA Technical Reports Server (NTRS)

Zimmerli, Gregory A.; Berg, Robert F.; Moldover, Michael R.

1999-01-01

Why does water flow faster than honey? The short answer, that honey has a greater viscosity, merely rephrases the question. The fundamental answer is that viscosity originates in the interactions between a fluid s molecules. These interactions are so complicated that, except for low-density gases, the viscosity of a fluid cannot be accurately predicted. Progress in understanding viscosity has been made by studying moderately dense gases and, more recently, fluids near the critical point. Modern theories predict a universal behavior for all pure fluids near the liquid-vapor critical point, and they relate the increase in viscosity to spontaneous fluctuations in density near this point. The Critical Viscosity of Xenon (CVX) experiment tested these theories with unprecedented precision when it flew aboard the Space Shuttle Discovery (STS-85) in August 1997. Near the critical point, xenon is a billion times more compressible than water, yet it has about the same density. Because the fluid is so "soft," it collapses under its own weight when exposed to the force of Earth s gravity - much like a very soft spring. Because the CVX experiment is conducted in microgravity, it achieves a very uniform fluid density even very close to the critical point. At the heart of the CVX experiment is a novel viscometer built around a small nickel screen. An oscillating electric field forces the screen to oscillate between pairs of electrodes. Viscosity, which dampens the oscillations, can be calculated by measuring the screen motion and the force applied to the screen. So that the fluid s delicate state near the critical point will not be disrupted, the screen oscillations are set to be both slow and small.

Jorge A. Swieca's contributions to quantum field theory in the 60s and 70s and their relevance in present research

NASA Astrophysics Data System (ADS)

Schroer, B.

2010-07-01

After revisiting some high points of particle physics and QFT of the two decades from 1960 to 1980, I comment on the work by Jorge André Swieca. I explain how it fits into the quantum field theory during these two decades and draw attention to its relevance to the ongoing particle physics research. A particular aim of this article is to direct the readers mindfulness to the relevance of what at the time of Swieca was called “the Schwinger Higgs screening mechanism” which, together with recent ideas which generalize the concept of gauge theories, has all the ingredients to revolutionize the issue of gauge theories and the standard model.

Message Design Guidelines For Screen-Based Programs.

ERIC Educational Resources Information Center

Rimar, G. I.

1996-01-01

Effective message design for screen-based computer or video instructional programs requires knowledge from many disciplines. Evaluates current conventions and suggests a new set of guidelines for screen-based designers. Discusses screen layout, highlighting and cueing, text font and style, text positioning, color, and graphical user interfaces for…

Measuring the psychosocial consequences of screening

PubMed Central

Brodersen, John; McKenna, Stephen P; Doward, Lynda C; Thorsen, Hanne

2007-01-01

The last three decades have seen a dramatic rise in the implementation of screening programmes for cancer in industrialised countries. However, in contrast to screening for infectious diseases, most cancer screening programmes only have the potential to reduce mortality; they cannot lower the incidence of cancer in a population. In fact, most cancer screening programmes have been shown to increase the incidence of the disease as a consequence of over-diagnosis. A further dilemma of cancer screening programmes is that they do not distinguish between healthy people and those with disease. Rather, they identify a continuum of disease severity. Consequently, many healthy people who have abnormal screening tests are wrongly diagnosed. Indeed, studies have demonstrated that for each screening-prevented death from cancer, at least 200 false-positive results are given. Therefore, screening has the potential to be harmful as well as beneficial. The psychosocial consequences of false-positive screening results cannot be determined by diagnostic tests or by other technical means. Instead, patient reported outcome measures must be employed. To measure the outcomes of screening accurately and comprehensively patient reported outcome measures have to capture; the nature and extent of the psychosocial consequences and how these change over time. The outcome measures used must have high content validity and their psychometric properties should be determined prior to their use in the specific population. In particular it is important to establish unidimensionality, additivity and item ordering through the application of Item Response Theory. PMID:17210071

Decision Aid to Technologically Enhance Shared decision making (DATES): study protocol for a randomized controlled trial

PubMed Central

2013-01-01

Background Clinicians face challenges in promoting colorectal cancer screening due to multiple competing demands. A decision aid that clarifies patient preferences and improves decision quality can aid shared decision making and be effective at increasing colorectal cancer screening rates. However, exactly how such an intervention improves shared decision making is unclear. This study, funded by the National Cancer Institute, seeks to provide detailed understanding of how an interactive decision aid that elicits patient’s risks and preferences impacts patient-clinician communication and shared decision making, and ultimately colorectal cancer screening adherence. Methods/Design This is a two-armed single-blinded randomized controlled trial with the target of 300 patients per arm. The setting is eleven community and three academic primary care practices in Metro Detroit. Patients are men and women aged between 50 and 75 years who are not up to date on colorectal cancer screening. ColoDATES Web (intervention arm), a decision aid that incorporates interactive personal risk assessment and preference clarification tools, is compared to a non-interactive website that matches ColoDATES Web in content but does not contain interactive tools (control arm). Primary outcomes are patient uptake of colorectal cancer screening; patient decision quality (knowledge, preference clarification, intent); clinician’s degree of shared decision making; and patient-clinician concordance in the screening test chosen. Secondary outcome incorporates a Structural Equation Modeling approach to understand the mechanism of the causal pathway and test the validity of the proposed conceptual model based on Theory of Planned Behavior. Clinicians and those performing the analysis are blinded to arms. Discussion The central hypothesis is that ColoDATES Web will improve colorectal cancer screening adherence through improvement in patient behavioral factors, shared decision making between the patient and the clinician, and concordance between the patient’s and clinician’s preferred colorectal cancer screening test. The results of this study will be among the first to examine the effect of a real-time preference assessment exercise on colorectal cancer screening and mediators, and, in doing so, will shed light on the patient-clinician communication and shared decision making ‘black box’ that currently exists between the delivery of decision aids to patients and subsequent patient behavior. Trial Registration ClinicalTrials.gov ID NCT01514786 PMID:24216139

Development and community-based validation of eight item banks to assess mental health.

PubMed

Batterham, Philip J; Sunderland, Matthew; Carragher, Natacha; Calear, Alison L

2016-09-30

There is a need for precise but brief screening of mental health problems in a range of settings. The development of item banks to assess depression and anxiety has resulted in new adaptive and static screeners that accurately assess severity of symptoms. However, expansion to a wider array of mental health problems is required. The current study developed item banks for eight mental health problems: social anxiety disorder, panic disorder, post-traumatic stress disorder, obsessive-compulsive disorder, adult attention-deficit hyperactivity disorder, drug use, psychosis and suicidality. The item banks were calibrated in a population-based Australian adult sample (N=3175) by administering large item pools (45-75 items) and excluding items on the basis of local dependence or measurement non-invariance. Item Response Theory parameters were estimated for each item bank using a two-parameter graded response model. Each bank consisted of 19-47 items, demonstrating excellent fit and precision across a range of -1 to 3 standard deviations from the mean. No previous study has developed such a broad range of mental health item banks. The calibrated item banks will form the basis of a new system of static and adaptive measures to screen for a broad array of mental health problems in the community. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Machine learning-based screening of complex molecules for polymer solar cells

NASA Astrophysics Data System (ADS)

Jørgensen, Peter Bjørn; Mesta, Murat; Shil, Suranjan; García Lastra, Juan Maria; Jacobsen, Karsten Wedel; Thygesen, Kristian Sommer; Schmidt, Mikkel N.

2018-06-01

Polymer solar cells admit numerous potential advantages including low energy payback time and scalable high-speed manufacturing, but the power conversion efficiency is currently lower than for their inorganic counterparts. In a Phenyl-C_61-Butyric-Acid-Methyl-Ester (PCBM)-based blended polymer solar cell, the optical gap of the polymer and the energetic alignment of the lowest unoccupied molecular orbital (LUMO) of the polymer and the PCBM are crucial for the device efficiency. Searching for new and better materials for polymer solar cells is a computationally costly affair using density functional theory (DFT) calculations. In this work, we propose a screening procedure using a simple string representation for a promising class of donor-acceptor polymers in conjunction with a grammar variational autoencoder. The model is trained on a dataset of 3989 monomers obtained from DFT calculations and is able to predict LUMO and the lowest optical transition energy for unseen molecules with mean absolute errors of 43 and 74 meV, respectively, without knowledge of the atomic positions. We demonstrate the merit of the model for generating new molecules with the desired LUMO and optical gap energies which increases the chance of finding suitable polymers by more than a factor of five in comparison to the randomised search used in gathering the training set.

Dielectric screening of early differentiation patterns in mesenchymal stem cells induced by steroid hormones.

PubMed

Ron, Amit; Shur, Irena; Daniel, Ramiz; Singh, Ragini Raj; Fishelson, Nick; Croitoru, Nathan; Benayahu, Dafna; Shacham-Diamand, Yosi

2010-06-01

In the framework of this study, target identification and localization of differentiation patterns by means of dielectric spectroscopy is presented. Here, a primary pre-osteoblastic bone marrow-derived MBA-15 cellular system was used to study the variations in the dielectric properties of mesenchymal stem cells while exposed to differentiation regulators. Using the fundamentals of mixed dielectric theories combined with finite numerical tools, the permittivity spectra of MBA-15 cell suspensions have been uniquely analyzed after being activated by steroid hormones to express osteogenic phenotypes. Following the spectral analysis, significant variations were revealed in the dielectric properties of the activated cells in comparison to the untreated populations. Based on the differentiation patterns of MBA-15, the electrical modifications were found to be highly correlated with the activation of specific cellular mechanisms which directly react to the hormonal inductions. In addition, by describing the dielectric dispersion in terms of transfer functions, it is shown that the spectral perturbations are well adapted to variations in the electrical characteristics of the cells. The reported findings vastly emphasize the tight correlation between the cellular and electrical state of the differentiated cells. It therefore emphasizes the vast abilities of impedance-based techniques as potential screening tools for stem cell analysis. Copyright 2009 Elsevier B.V. All rights reserved.

Spectral methods in edge-diffraction theories

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

Arnold, J.M.

Spectral methods for the construction of uniform asymptotic representations of the field diffracted by an aperture in a plane screen are reviewed. These are separated into contrasting approaches, roughly described as physical and geometrical. It is concluded that the geometrical methods provide a direct route to the construction of uniform representations that are formally identical to the equivalent-edge-current concept. Some interpretive and analytical difficulties that complicate the physical methods of obtaining uniform representations are analyzed. Spectral synthesis proceeds directly from the ray geometry and diffraction coefficients, without any intervening current representation, and the representation is uniform at shadow boundaries andmore » caustics of the diffracted field. The physical theory of diffraction postulates currents on the diffracting screen that give rise to the diffracted field. The difficulties encountered in evaluating the current integrals are throughly examined, and it is concluded that the additional data provided by the physical theory of diffraction (diffraction coefficients off the Keller diffraction cone) are not actually required for obtaining uniform asymptotics at the leading order. A new diffraction representation that generalizes to arbitrary plane-convex apertures a formula given by Knott and Senior [Proc. IEEE 62, 1468 (1974)] for circular apertures is deduced. 34 refs., 1 fig.« less

Performance of different theories for the angular distribution of bremsstrahlung produced by keV electrons incident upon a target

NASA Astrophysics Data System (ADS)

Omar, Artur; Andreo, Pedro; Poludniowski, Gavin

2018-07-01

Different theories of the intrinsic bremsstrahlung angular distribution (i.e., the shape function) have been evaluated using Monte Carlo calculations for various target materials and incident electron energies between 20 keV and 300 keV. The shape functions considered were the plane-wave first Born approximation cross sections (i) 2BS [high-energy result, screened nucleus], (ii) 2BN [general result, bare nucleus], (iii) KM [2BS modified to emulate 2BN], and (iv) SIM [leading term of 2BN]; (v) expression based on partial-waves expansion, KQP; and (vi) a uniform spherical distribution, UNI [a common approximation in certain analytical models]. The shape function was found to have an important impact on the bremsstrahlung emerging from thin foil targets in which the incident electrons undergo few elastic scatterings before exiting the target material. For thick transmission and reflection targets the type of shape function had less importance, as the intrinsic bremsstrahlung angular distribution was masked by the diffuse directional distribution of multiple scattered electrons. Predictions made using the 2BN and KQP theories were generally in good agreement, suggesting that the effect of screening and the constraints of the Born approximation on the intrinsic angular distribution may be acceptable. The KM and SIM shape functions deviated notably from KQP for low electron energies (< 50 keV), while 2BS and UNI performed poorly over most of the energy range considered; the 2BS shape function was found to be too forward-focused in emission, while UNI was not forward-focused enough. The results obtained emphasize the importance of the intrinsic bremsstrahlung angular distribution for theoretical predictions of x-ray emission, which is relevant in various applied disciplines, including x-ray crystallography, electron-probe microanalysis, security and industrial inspection, medical imaging, as well as low- and medium (orthovoltage) energy radiotherapy.

The comparative and cost-effectiveness of HPV-based cervical cancer screening algorithms in El Salvador.

PubMed

Campos, Nicole G; Maza, Mauricio; Alfaro, Karla; Gage, Julia C; Castle, Philip E; Felix, Juan C; Cremer, Miriam L; Kim, Jane J

2015-08-15

Cervical cancer is the leading cause of cancer death among women in El Salvador. Utilizing data from the Cervical Cancer Prevention in El Salvador (CAPE) demonstration project, we assessed the health and economic impact of HPV-based screening and two different algorithms for the management of women who test HPV-positive, relative to existing Pap-based screening. We calibrated a mathematical model of cervical cancer to epidemiologic data from El Salvador and compared three screening algorithms for women aged 30-65 years: (i) HPV screening every 5 years followed by referral to colposcopy for HPV-positive women (Colposcopy Management [CM]); (ii) HPV screening every 5 years followed by treatment with cryotherapy for eligible HPV-positive women (Screen and Treat [ST]); and (iii) Pap screening every 2 years followed by referral to colposcopy for Pap-positive women (Pap). Potential harms and complications associated with overtreatment were not assessed. Under base case assumptions of 65% screening coverage, HPV-based screening was more effective than Pap, reducing cancer risk by ∼ 60% (Pap: 50%). ST was the least costly strategy, and cost $2,040 per year of life saved. ST remained the most attractive strategy as visit compliance, costs, coverage, and test performance were varied. We conclude that a screen-and-treat algorithm within an HPV-based screening program is very cost-effective in El Salvador, with a cost-effectiveness ratio below per capita GDP. © 2015 UICC.

The 3-D viscous flow CFD analysis of the propeller effect on an advanced ducted propeller subsonic inlet

NASA Technical Reports Server (NTRS)

Iek, Chanthy; Boldman, Donald R.; Ibrahim, Mounir

1993-01-01

A time marching Navier-Stokes code called PARC3D was used to study the 3-D viscous flow associated with an advanced ducted propeller (ADP) subsonic inlet at take-off operating conditions. At a free stream Mach number of 0.2, experimental data for the inlet-with-propeller test model indicated that the airflow was attached on the cowl windward lip at an angle of attack of 25 degrees became unstable at 29 degrees, and separated at 30 degrees. An experimental study with a similar inlet and with no propeller (through-flow) indicated that flow separation occurred at an angle of attack a few degrees below the value observed when the inlet was tested with the propeller. This tends to indicate that the propeller exerts a favorable effect on the inlet performance. During the through-flow experiment a stationary blockage device was used to successfully simulate the propeller effect on the inlet flow field at angles of attack. In the present numerical study, this flow blockage was modeled via a PARC3D computational boundary condition (BC) called the screen BC. The principle formulation of this BC was based on the one-and-half dimension actuator disk theory. This screen BC was applied at the inlet propeller face station of the computational grid. Numerical results were obtained with and without the screen BC. The application of the screen BC in this numerical study provided results which are similar to the results of past experimental efforts in which either the blockage device or the propeller was used.

Resonant nuclear reaction 23Mg (p,γ) 24Al in strongly screening magnetized neutron star crust

NASA Astrophysics Data System (ADS)

Liu, Jing-Jing; Liu, Dong-Mei

2017-12-01

Based on the relativistic theory of superstrong magnetic fields (SMF), by using three models those of Lai (LD), Fushiki (FGP), and our own (LJ), we investigate the influence of SMFs due to strong electron screening (SES) on the nuclear reaction 23Mg (p,γ) 24Al in magnetars. In a relatively low density environment (e.g., ρ 7<0.01) and 1102), our reaction rates can be 1.58 times and about three orders of magnitude larger than those of FGP and LD, respectively (B 12, ρ 7 are in units of 1012G, 107g cm-3). The significant increase of strong screening rate can imply that more 23Mg will escape from the Ne-Na cycle due to SES in a SMF. As a consequence, the next reaction, 24Al (β+, ν) 24Mg, will produce more 24Mg to participate in the Mg-Al cycle. Thus, it may lead to synthesis of a large amount of A>20 nuclides in magnetars. Supported by National Natural Science Foundation of China (11565020), the Counterpart Foundation of Sanya (2016PT43), the Special Foundation of Science and Technology Cooperation for Advanced Academy and Regional of Sanya (2016YD28), the Scientific Research Starting Foundation for 515 Talented Project of Hainan Tropical Ocean University (RHDRC201701) and the Natural Science Foundation of Hainan Province (114012)