efficient gatekeeper algorithm: Topics by Science.gov

Sample records for efficient gatekeeper algorithm

GateKeeper: a new hardware architecture for accelerating pre-alignment in DNA short read mapping.

PubMed

Alser, Mohammed; Hassan, Hasan; Xin, Hongyi; Ergin, Oguz; Mutlu, Onur; Alkan, Can

2017-11-01

High throughput DNA sequencing (HTS) technologies generate an excessive number of small DNA segments -called short reads- that cause significant computational burden. To analyze the entire genome, each of the billions of short reads must be mapped to a reference genome based on the similarity between a read and 'candidate' locations in that reference genome. The similarity measurement, called alignment, formulated as an approximate string matching problem, is the computational bottleneck because: (i) it is implemented using quadratic-time dynamic programming algorithms and (ii) the majority of candidate locations in the reference genome do not align with a given read due to high dissimilarity. Calculating the alignment of such incorrect candidate locations consumes an overwhelming majority of a modern read mapper's execution time. Therefore, it is crucial to develop a fast and effective filter that can detect incorrect candidate locations and eliminate them before invoking computationally costly alignment algorithms. We propose GateKeeper, a new hardware accelerator that functions as a pre-alignment step that quickly filters out most incorrect candidate locations. GateKeeper is the first design to accelerate pre-alignment using Field-Programmable Gate Arrays (FPGAs), which can perform pre-alignment much faster than software. When implemented on a single FPGA chip, GateKeeper maintains high accuracy (on average >96%) while providing, on average, 90-fold and 130-fold speedup over the state-of-the-art software pre-alignment techniques, Adjacency Filter and Shifted Hamming Distance (SHD), respectively. The addition of GateKeeper as a pre-alignment step can reduce the verification time of the mrFAST mapper by a factor of 10. https://github.com/BilkentCompGen/GateKeeper. mohammedalser@bilkent.edu.tr or onur.mutlu@inf.ethz.ch or calkan@cs.bilkent.edu.tr. Supplementary data are available at Bioinformatics online. © The Author (2017). Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com
A gatekeeper chaperone complex directs translocator secretion during Type Three Secretion

DOE PAGES

Archuleta, Tara L.; Spiller, Benjamin W.; Kubori, Tomoko

2014-11-06

Many Gram-negative bacteria use Type Three Secretion Systems (T3SS) to deliver effector proteins into host cells. These protein delivery machines are composed of cytosolic components that recognize substrates and generate the force needed for translocation, the secretion conduit, formed by a needle complex and associated membrane spanning basal body, and translocators that form the pore in the target cell. A defined order of secretion in which needle component proteins are secreted first, followed by translocators, and finally effectors, is necessary for this system to be effective. While the secreted effectors vary significantly between organisms, the ~20 individual protein components thatmore » form the T3SS are conserved in many pathogenic bacteria. One such conserved protein, referred to as either a plug or gatekeeper, is necessary to prevent unregulated effector release and to allow efficient translocator secretion. The mechanism by which translocator secretion is promoted while effector release is inhibited by gatekeepers is unknown. We present the structure of the Chlamydial gatekeeper, CopN, bound to a translocator-specific chaperone. The structure identifies a previously unknown interface between gatekeepers and translocator chaperones and reveals that in the gatekeeper-chaperone complex the canonical translocator-binding groove is free to bind translocators. Thus, structure-based mutagenesis of the homologous complex in Shigella reveals that the gatekeeper-chaperone-translocator complex is essential for translocator secretion and for the ordered secretion of translocators prior to effectors.« less
Training of Attentional Filtering, but Not of Memory Storage, Enhances Working Memory Efficiency by Strengthening the Neuronal Gatekeeper Network.

PubMed

Schmicker, Marlen; Schwefel, Melanie; Vellage, Anne-Katrin; Müller, Notger G

2016-04-01

Memory training (MT) in older adults with memory deficits often leads to frustration and, therefore, is usually not recommended. Here, we pursued an alternative approach and looked for transfer effects of 1-week attentional filter training (FT) on working memory performance and its neuronal correlates in young healthy humans. The FT effects were compared with pure MT, which lacked the necessity to filter out irrelevant information. Before and after training, all participants performed an fMRI experiment that included a combined task in which stimuli had to be both filtered based on color and stored in memory. We found that training induced processing changes by biasing either filtering or storage. FT induced larger transfer effects on the untrained cognitive function than MT. FT increased neuronal activity in frontal parts of the neuronal gatekeeper network, which is proposed to hinder irrelevant information from being unnecessarily stored in memory. MT decreased neuronal activity in the BG part of the gatekeeper network but enhanced activity in the parietal storage node. We take these findings as evidence that FT renders working memory more efficient by strengthening the BG-prefrontal gatekeeper network. MT, on the other hand, simply stimulates storage of any kind of information. These findings illustrate a tight connection between working memory and attention, and they may open up new avenues for ameliorating memory deficits in patients with cognitive impairments.
Outcomes of senior reach gatekeeper referrals: comparison of the Spokane gatekeeper program, Colorado Senior Reach, and Mid-Kansas Senior Outreach.

PubMed

Bartsch, David A; Rodgers, Vicki K; Strong, Don

2013-01-01

Outcomes of older adults referred for care management and mental health services through the senior reach gatekeeper model of case finding were examined in this study and compared with the Spokane gatekeeper model Colorado Senior Reach and the Mid-Kansas Senior Outreach (MKSO) programs are the two Senior Reach Gatekeeper programs modeled after the Spokane program, employing the same community education and gatekeeper model and with mental health treatment for elderly adults in need of support. The three mature programs were compared on seniors served isolation, and depression ratings. Nontraditional community gatekeepers were trained and referred seniors in need. Findings indicate that individuals served by the two Senior Reach Gatekeeper programs demonstrated significant improvements. Isolation indicators such as social isolation decreased and depression symptoms and suicide ideation also decreased. These findings for two Senior Reach Gatekeeper programs demonstrate that the gatekeeper approach to training community partners worked in referring at-risk seniors in need in meeting their needs, and in having a positive impact on their lives.
Does a brief suicide prevention gatekeeper training program enhance observed skills?

PubMed

Cross, Wendi; Matthieu, Monica M; Lezine, Dequincy; Knox, Kerry L

2010-01-01

Suicide is a significant public health problem worldwide that requires evidence-based prevention efforts. One approach to prevention is gatekeeper training. Gatekeeper training programs for community members have demonstrated positive changes in knowledge and attitudes about suicide. Changes in gatekeeper skills have not been well established. To assess and to predict the impact of a brief, gatekeeper training on community members' observed skills. Participants in a community gatekeeper training were employees at US universities. 50 participants were randomly selected for skills assessment and videotaped interacting with a standardized actor prior to and following training. Tapes were reliably rated for general and suicide-specific skills. Gatekeeper skills increased from pre- to posttest: 10% of participants met criteria for acceptable gatekeeper skills before training, while 54% met criteria after training. Pretraining variables did not predict increased skills. Results do not provide conclusions about the relationship between observed gatekeeper skills and actual use of those skills in the future. Gatekeeper training enhances suicide-specific skills for the majority of participants. Other strategies, such as behavioral rehearsal, may be necessary to enhance skills in the remaining participants.
Does a brief suicide prevention gatekeeper training program enhance observed skills?

PubMed Central

Cross, Wendi; Matthieu, Monica M.; Lezine, DeQuincy; Knox, Kerry L.

2010-01-01

Background Suicide is a significant public health problem worldwide that requires evidence-based prevention efforts. One approach to prevention is gatekeeper training. Gatekeeper training programs for community members have demonstrated positive changes in knowledge and attitudes about suicide. Changes in gatekeeper skills have not been well established. Aims To assess and predict the impact of a brief, gatekeeper training on community members’ observed skills. Methods Participants in a community gatekeeper training were employees at US universities. 50 participants were randomly selected for skills assessment and videotaped interacting with a standardized actor prior to and following training. Tapes were reliability rated for general and suicide-specific skills. Results Gatekeeper skills increased from pre- to posttest: 10% of participants met criteria for acceptable gatekeeper skills before training, while 54% met criteria after training. Pretraining variables did not predict increased skills. Limitations Results do not provide conclusions about the relationship between observed gatekeeper skills and actual use of those skills in the future. Conclusions Gatekeeper training enhances suicide-specific skills for the majority of participants. Other strategies, such as behavioral rehearsal, may be necessary to enhance skills in the remaining participants. PMID:20573609
An Overview on Coronary Heart Disease (A Comparative Evaluation of Turkey and Europe) and Cost-effectiveness of Diagnostic Strategies

PubMed Central

Taşçı, Cengiz; Özçelik, Nihat

2011-01-01

Objective: Coronary heart disease (CHD) is the leading cause of death for men and women in Turkey as it is in Europe and US. The prevalence of the disease is 3.8% in Turkey and 200,000 patients are added to the pool of CHD annually Because of genetic predisposition and high proportions of physical inactivity, smoking habit, and obesity, CHD is encountered in earlier ages in our country So, the economic burden of the disease is expected to be relatively high, but the amount of health expenditure is not always parallel to the prevalence of a disease in the community. This article was written to overview CHD statistics to make a comparison between Turkey and some European countries and to investigate the value of myocardial perfusion scan (MPS) as a gatekeeper in diagnosing CHD before invasive coronary angiography (ICA). The consequences were evaluated for Turkey In diagnosis; noninvasive testing gains importance in connection with the new approaches in treatment strategies, because a direct ICA strategy results in higher rates of revascularization without improvement in clinical outcomes. A "gatekeeper" is needed to select the patients who are not required to undergo angiography. MPS with its proved power in diagnosis and predicting prognosis, provides a cost-effective solution, and is accepted in some extensive analyses as a "gatekeeper" particularly in intermediate and high risk patients and in patients with known CHD. In conclusion, MPS may provide an optimal solution better than the ongoing situation in Turkey as well, when it is approved as a "gatekeeper in an algorithm before ICA. Conflict of interest:None declared. PMID:23487016
Not a "mom thing": Predictors of gatekeeping in same-sex and heterosexual parent families.

PubMed

Sweeney, Kristin K; Goldberg, Abbie E; Garcia, Randi L

2017-08-01

The current study is the first to examine parental gatekeeping in both same-sex (57 female, 51 male) and heterosexual (n = 82) couples, all of whom became parents via adoption. Aspects of the individual, the couple, and the work context, measured preadoption, were examined as predictors of gatekeeping. Gatekeeping refers to attitudes and behaviors aimed at regulating and limiting the involvement of the other parent in housework and child care and was measured 2 years postadoption. Findings revealed that women in heterosexual relationships reported higher gatekeeping compared with all other groups, and men in same-sex relationships reported higher gatekeeping compared with women in same-sex relationships and men in heterosexual relationships. Across the full sample, lower job autonomy predicted higher gatekeeping in both housework and child care, whereas greater relationship ambivalence, greater perceived parenting skill, and lower perceived partner parenting skill predicted higher gatekeeping in child care. Findings provide insight into how gatekeeping behaviors and beliefs are enacted in diverse types of couples and suggest that work factors should be taken into account when conducting research on, and seeking to improve, coparenting relationships. (PsycINFO Database Record (c) 2017 APA, all rights reserved).
Determinants of healthcare system's efficiency in OECD countries.

PubMed

Hadad, Sharon; Hadad, Yossi; Simon-Tuval, Tzahit

2013-04-01

Firstly, to compare healthcare systems' efficiency (HSE) using two models: one incorporating mostly inputs that are considered to be within the discretionary control of the healthcare system (i.e., physicians' density, inpatient bed density, and health expenditure), and another, including mostly inputs beyond healthcare systems' control (i.e., GDP, fruit and vegetables consumption, and health expenditure). Secondly, analyze whether institutional arrangements, population behavior, and socioeconomic or environmental determinants are associated with HSE. Data envelopment analysis (DEA) was utilized to calculate OECD countries' HSE. Life expectancy and infant survival rate were considered as outputs in both models. Healthcare systems' rankings according to the super-efficiency and the cross-efficiency ranking methods were used to analyze determinants associated with efficiency. (1) Healthcare systems in nine countries with large and stable economies were defined as efficient in model I, but were found to be inefficient in model II; (2) Gatekeeping and the presence of multiple insurers were associated with a lower efficiency; and (3) The association between socioeconomic and environmental indicators was found to be ambiguous. Countries striving to improve their HSE should aim to impact population behavior and welfare rather than only ensure adequate medical care. In addition, they may consider avoiding specific institutional arrangements, namely gatekeeping and the presence of multiple insurers. Finally, the ambiguous association found between socioeconomic and environmental indicators, and a country's HSE necessitates caution when interpreting different ranking techniques in a cross-country efficiency evaluation and needs further exploration.
The Loss of Innocence: Emotional Costs to Serving as Gatekeepers to the Counseling Profession

ERIC Educational Resources Information Center

Kerl, Stella; Eichler, Margaret

2005-01-01

The practice of gatekeeping within the profession of counseling is well documented in the literature. Counselor educators are charged with the responsibility of serving as gatekeepers for the profession. However, a number of factors inhibit the practice of gatekeeping, including fears of retribution, loss, or damage. At the same time, failure to…
The home food environment of overweight gatekeepers in the Netherlands.

PubMed

Poelman, Maartje P; de Vet, Emely; Velema, Elizabeth; Seidell, Jacob C; Steenhuis, Ingrid H M

2015-07-01

The aim of the present study was to gain insight into (i) processed snack-food availability, (ii) processed snack-food salience and (iii) the size of dinnerware among households with overweight gatekeepers. Moreover, associations between gatekeepers' characteristics and in-home observations were determined. A cross-sectional observation of home food environments was conducted as part of a baseline measurement of a larger study. Home food environments of overweight and obese gatekeepers in the Netherlands. Household gatekeepers (n 278). Mean household size of the gatekeepers was 3.0 (SD 1.3) persons. Mean age of the gatekeepers was 45.7 (SD 9.2) years, 34.9% were overweight and 65.1% were obese. Of the gatekeepers, 20.9% had a low level of education and 42.7% had a high level of education. In 70% of the households, eight or more packages of processed snack foods were present. In 54% of the households, processed snack foods were stored close to non-processed food items and in 78% of households close to non-food items. In 33% of the households, processed snack foods were visible in the kitchen and in 15% of the households processed snack foods were visible in the living room. Of the dinnerware items, 14% (plates), 57% (glasses), 78% (dessert bowls), 67% (soup bowls) and 58% (mugs) were larger than the reference norms of the Netherlands Nutrition Centre Foundation. Older gatekeepers used significantly smaller dinnerware than younger gatekeepers. Environmental factors endorsing overconsumption are commonly present in the home environments of overweight people and could lead to unplanned eating or passive overconsumption.
Engineering Nucleotide Specificity of Succinyl-CoA Synthetase in Blastocystis: The Emerging Role of Gatekeeper Residues.

PubMed

Vashisht, Kapil; Verma, Sonia; Gupta, Sunita; Lynn, Andrew M; Dixit, Rajnikant; Mishra, Neelima; Valecha, Neena; Hamblin, Karleigh A; Maytum, Robin; Pandey, Kailash C; van der Giezen, Mark

2017-01-24

Charged, solvent-exposed residues at the entrance to the substrate binding site (gatekeeper residues) produce electrostatic dipole interactions with approaching substrates, and control their access by a novel mechanism called "electrostatic gatekeeper effect". This proof-of-concept study demonstrates that the nucleotide specificity can be engineered by altering the electrostatic properties of the gatekeeper residues outside the binding site. Using Blastocystis succinyl-CoA synthetase (SCS, EC 6.2.1.5), we demonstrated that the gatekeeper mutant (ED) resulted in ATP-specific SCS to show high GTP specificity. Moreover, nucleotide binding site mutant (LF) had no effect on GTP specificity and remained ATP-specific. However, via combination of the gatekeeper mutant with the nucleotide binding site mutant (ED+LF), a complete reversal of nucleotide specificity was obtained with GTP, but no detectable activity was obtained with ATP. This striking result of the combined mutant (ED+LF) was due to two changes; negatively charged gatekeeper residues (ED) favored GTP access, and nucleotide binding site residues (LF) altered ATP binding, which was consistent with the hypothesis of the "electrostatic gatekeeper effect". These results were further supported by molecular modeling and simulation studies. Hence, it is imperative to extend the strategy of the gatekeeper effect in a different range of crucial enzymes (synthetases, kinases, and transferases) to engineer substrate specificity for various industrial applications and substrate-based drug design.
Intention to Enact and Enactment of Gatekeeper Behaviors for Suicide Prevention: an Application of the Theory of Planned Behavior.

PubMed

Kuhlman, Shane T W; Walch, Susan E; Bauer, Kristina N; Glenn, April D

2017-08-01

Gatekeeper training for suicide prevention was evaluated on a college campus to examine the impact of training on gatekeeper enactment of behaviors in support of suicide prevention and identify predictors of enactment of gatekeeper behaviors. Trained gatekeepers (N = 216) displayed greater perceived knowledge and self-efficacy for suicide prevention and reported higher rates of self-reported actual gatekeeper behaviors, including inquiring about suicidal ideation and referring for mental health treatment when they encountered someone in distress, compared to their untrained counterparts (N = 169). Consistent with the Theory of Planned Behavior, SEM results indicated that attitudes, self-efficacy, and perceived knowledge explained intentions to engage in gatekeeper behaviors, accounting for 59% of the variance in intentions to inquire about suicidal ideation and supporting the role of attitudes and perceived behavioral control in intentions to act. These intentions explained self-reported actual gatekeeper behaviors among participants who encountered someone in distress, with each one-point increase in intention associated with nearly twice the likelihood of both inquiring about suicidal ideation and referring someone for mental health care. On the other hand, self-reported situational barriers were associated with a decreased likelihood of referral behavior, indicating the role of actual behavioral control over volitional actions. Findings support the value of gatekeeper training for promoting factors that influence the likelihood of action on behalf of suicide prevention.
Entry one: striving for best practice in professional assessment.

PubMed

English, Justin M; Mykyta, Lu

2002-01-01

The aim of this study was to develop a best practice model of professional assessment to ensure efficient and effective delivery of home-based services to frail and disabled elders. In 2000, an innovative model of professional assessment was introduced by one of Australia's largest providers of home-based care in order to reduce multiple assessments and to reduce the utilisation of assessment as a gatekeeping tool for limiting access to services. Data was analysed from a random sample of 1500 clients drawn from a population of 5000 as well as through the use of a survey tool administered to the Organisation's assessment staff and other key stakeholders. Results revealed that, contrary to popular belief, carer advocacy plays a significant role in the professional assessment process to the point that clients with carers received significantly more services and service time that clients without such support. However, if not monitored, assessment can also be used as a gate-keeping tool as opposed to one that can provide significant benefits to the consumers through comprehensive need articulation. We argue that the "professional" approach does not preclude empowerment and that assessment should not be used as a gate-keeping tool.
Patients’ Willingness on Community Health Centers as Gatekeepers and Associated Factors in Shenzhen, China

PubMed Central

Gan, Yong; Li, Wenzhen; Cao, Shiyi; Dong, Xiaoxin; Li, Liqing; Mkandawire, Naomie; Chen, Yawen; Herath, Chulani; Song, Xingyue; Yin, Xiaoxv; Yang, Tingting; Li, Jing; Deng, Jian; Lu, Zuxun

2016-01-01

Abstract The gate-keeping function of primary healthcare facilities has not been fully implemented in China. This study was aiming at assessing the willingness on community health centers (CHCs) as gatekeepers among a sample of patients and investigating the influencing factors. A cross-sectional survey was conducted in 2013. A total of 7761 patients aged 18 to 90 years from 8 CHCs in Shenzhen (China) were interviewed using a structured questionnaire. Descriptive and multivariable logistic regression analyses were used to analyze the characteristics of patients, their willingness on the gatekeeper policy, and identify the associated factors. On willingness of patients to select CHCs as gatekeepers, 70.03% of respondents were willing, 18.95% were neutral, and 9.02% were unwilling. Multivariable analysis indicated that female patients (odds ratio [OR] = 1.15, 95% confidence interval [CI]: 1.02–1.30); patients with health insurance (OR = 1.21, 95% CI: 1.07–1.36); patients who lives near CHC (OR = 1.89, 95% CI: 1.17–3.05); and patients who were more familiar with the gatekeeper policy (OR = 2.09, 95% CI: 1.85–2.36), had higher level of willingness on the policy. Conversely, reporting with good health status was independently associated with the decreased willingness on gatekeeper policy (OR = 0.69, 95% CI: 0.53–0.90). The findings indicated that patients’ willingness on CHCs as gatekeepers is high. More priority measures, such as expanding medical insurance coverage of patients, strengthening the propaganda of gatekeeper policy, and increasing the access to community health service, are warranted to be taken. This will help to further improve the patients’ willingness on CHCs as gatekeepers. It is thus feasible to implement the gatekeeper policy among patients in China. PMID:27057877
[General practitioners as gatekeepers: Better health care than in countries with self-referral to specialists?].

PubMed

Groenewegen, Peter

2016-01-01

In the Netherlands and a number of other European countries general practitioners are the gatekeepers for specialist and hospital care. European health care systems with gatekeeping general practitioners, i.e. those with comprehensive, strong primary care, perform better on a number of health indicators and on equity. However, it is less clear if gatekeeping health care systems have lower health expenditure. There is ongoing debate on whether gatekeeping plays a role in diagnostic delay of cancers. At health care system level research is being hampered by small numbers and should be combined with in-depth research into health care mechanisms.
Who are the Gatekeepers? Predictors of Maternal Gatekeeping

PubMed Central

Schoppe-Sullivan, Sarah J.; Altenburger, Lauren E.; Lee, Meghan A.; Bower, Daniel J.; Kamp Dush, Claire M.

2016-01-01

SYNOPSIS Objective The goal of this study was to identify determinants of maternal gatekeeping at the transition to parenthood. Design Participants included 182 different-gender dual-earner couples. During pregnancy, expectant parents completed questionnaires regarding their psychological functioning, attitudes, and expectations, and at 3 months postpartum questionnaires regarding maternal gatekeeping behavior and gate closing attitudes. Results SEM analyses revealed that mothers were more likely to close the gate to fathers when mothers held greater perfectionistic expectations for fathers’ parenting, had poorer psychological functioning, perceived their romantic relationship as less stable, and had higher levels of parenting self-efficacy. In contrast, fathers with lower parenting self-efficacy appeared to elicit greater maternal gate closing behavior. Mothers who engaged in greater gate opening behavior were more religious. Conclusions Maternal gatekeeping may be more strongly associated with maternal expectations and psychological functioning than with maternal traditional gender attitudes. Fathers’ characteristics are less predictive of maternal gatekeeping than mothers’ characteristics. PMID:27366115
Who are the Gatekeepers? Predictors of Maternal Gatekeeping.

PubMed

Schoppe-Sullivan, Sarah J; Altenburger, Lauren E; Lee, Meghan A; Bower, Daniel J; Kamp Dush, Claire M

The goal of this study was to identify determinants of maternal gatekeeping at the transition to parenthood. Participants included 182 different-gender dual-earner couples. During pregnancy, expectant parents completed questionnaires regarding their psychological functioning, attitudes, and expectations, and at 3 months postpartum questionnaires regarding maternal gatekeeping behavior and gate closing attitudes. SEM analyses revealed that mothers were more likely to close the gate to fathers when mothers held greater perfectionistic expectations for fathers' parenting, had poorer psychological functioning, perceived their romantic relationship as less stable, and had higher levels of parenting self-efficacy. In contrast, fathers with lower parenting self-efficacy appeared to elicit greater maternal gate closing behavior. Mothers who engaged in greater gate opening behavior were more religious. Maternal gatekeeping may be more strongly associated with maternal expectations and psychological functioning than with maternal traditional gender attitudes. Fathers' characteristics are less predictive of maternal gatekeeping than mothers' characteristics.
A mesoporous nanocontainer gated by a stimuli-responsive peptide for selective triggering of intracellular drug release

NASA Astrophysics Data System (ADS)

Lee, Jeonghun; Oh, Eun-Taex; Yoon, Haerry; Kim, Hyunmi; Park, Heon Joo; Kim, Chulhee

2016-04-01

Mesoporous silica nanocontainers (MSNs) with biologically responsive gatekeepers have great potential for effective delivery of cargo molecules to the desired sites. For that purpose, peptides could be effective candidates as gatekeepers because of their bioresponsiveness and targeting capability. Taking advantage of the zinc finger domain peptide (CXXC), we designed a biocompatible all-peptide gatekeeper (WCGKC) with on-off gatekeeping capability through stimulus-responsive conformational conversion and the steric bulkiness of the tryptophan unit. The turn structure induced by an intramolecular disulfide bond of the peptide gatekeeper (WCGKC-SS) completely inhibited the release of the entrapped doxorubicin (DOX). However, upon reduction of the disulfide bond by glutathione (GSH), the peptide conformation was converted to a random structure, which opened the orifice of the mesopore leading to the release of DOX. The amine moiety of the lysine of the peptide gatekeeper was PEGylated to enhance dispersion stability and biocompatibility of the nanocontainer. Furthermore, the MSNs with the peptide gatekeeper (PEG-WCGKC-SS-Si) selectively released the entrapped DOX in A549 human lung cancer cells in a controlled manner triggered by intracellular GSH, but not in CCD normal lung cells containing a low intracellular GSH level. In A549 cells, DOX-loaded PEG-WCGKC-SS-Si exhibited about 10-times higher cytotoxicity induced by apoptosis than that in CCD cells.Mesoporous silica nanocontainers (MSNs) with biologically responsive gatekeepers have great potential for effective delivery of cargo molecules to the desired sites. For that purpose, peptides could be effective candidates as gatekeepers because of their bioresponsiveness and targeting capability. Taking advantage of the zinc finger domain peptide (CXXC), we designed a biocompatible all-peptide gatekeeper (WCGKC) with on-off gatekeeping capability through stimulus-responsive conformational conversion and the steric bulkiness of the tryptophan unit. The turn structure induced by an intramolecular disulfide bond of the peptide gatekeeper (WCGKC-SS) completely inhibited the release of the entrapped doxorubicin (DOX). However, upon reduction of the disulfide bond by glutathione (GSH), the peptide conformation was converted to a random structure, which opened the orifice of the mesopore leading to the release of DOX. The amine moiety of the lysine of the peptide gatekeeper was PEGylated to enhance dispersion stability and biocompatibility of the nanocontainer. Furthermore, the MSNs with the peptide gatekeeper (PEG-WCGKC-SS-Si) selectively released the entrapped DOX in A549 human lung cancer cells in a controlled manner triggered by intracellular GSH, but not in CCD normal lung cells containing a low intracellular GSH level. In A549 cells, DOX-loaded PEG-WCGKC-SS-Si exhibited about 10-times higher cytotoxicity induced by apoptosis than that in CCD cells. Electronic supplementary information (ESI) available. See DOI: 10.1039/c5nr09280a
The m-AAA Protease Associated with Neurodegeneration Limits MCU Activity in Mitochondria.

PubMed

König, Tim; Tröder, Simon E; Bakka, Kavya; Korwitz, Anne; Richter-Dennerlein, Ricarda; Lampe, Philipp A; Patron, Maria; Mühlmeister, Mareike; Guerrero-Castillo, Sergio; Brandt, Ulrich; Decker, Thorsten; Lauria, Ines; Paggio, Angela; Rizzuto, Rosario; Rugarli, Elena I; De Stefani, Diego; Langer, Thomas

2016-10-06

Mutations in subunits of mitochondrial m-AAA proteases in the inner membrane cause neurodegeneration in spinocerebellar ataxia (SCA28) and hereditary spastic paraplegia (HSP7). m-AAA proteases preserve mitochondrial proteostasis, mitochondrial morphology, and efficient OXPHOS activity, but the cause for neuronal loss in disease is unknown. We have determined the neuronal interactome of m-AAA proteases in mice and identified a complex with C2ORF47 (termed MAIP1), which counteracts cell death by regulating the assembly of the mitochondrial Ca 2+ uniporter MCU. While MAIP1 assists biogenesis of the MCU subunit EMRE, the m-AAA protease degrades non-assembled EMRE and ensures efficient assembly of gatekeeper subunits with MCU. Loss of the m-AAA protease results in accumulation of constitutively active MCU-EMRE channels lacking gatekeeper subunits in neuronal mitochondria and facilitates mitochondrial Ca 2+ overload, mitochondrial permeability transition pore opening, and neuronal death. Together, our results explain neuronal loss in m-AAA protease deficiency by deregulated mitochondrial Ca 2+ homeostasis. Copyright © 2016 Elsevier Inc. All rights reserved.

Does Practice Make Perfect? A Randomized Control Trial of Behavioral Rehearsal on Suicide Prevention Gatekeeper Skills

PubMed Central

Seaburn, David; Gibbs, Danette; Schmeelk-Cone, Karen; White, Ann Marie; Caine, Eric D.

2011-01-01

Suicide is the third leading cause of death among 10–24-year-olds and the target of school-based prevention efforts. Gatekeeper training, a broadly disseminated prevention strategy, has been found to enhance participant knowledge and attitudes about intervening with distressed youth. Although the goal of training is the development of gatekeeper skills to intervene with at-risk youth, the impact on skills and use of training is less known. Brief gatekeeper training programs are largely educational and do not employ active learning strategies such as behavioral rehearsal through role play practice to assist skill development. In this study, we compare gatekeeper training as usual with training plus brief behavioral rehearsal (i.e., role play practice) on a variety of learning outcomes after training and at follow-up for 91 school staff and 56 parents in a school community. We found few differences between school staff and parent participants. Both training conditions resulted in enhanced knowledge and attitudes, and almost all participants spread gatekeeper training information to others in their network. Rigorous standardized patient and observational methods showed behavioral rehearsal with role play practice resulted in higher total gatekeeper skill scores immediately after training and at follow-up. Both conditions, however, showed decrements at follow-up. Strategies to strengthen and maintain gatekeeper skills over time are discussed. PMID:21814869
Does practice make perfect? A randomized control trial of behavioral rehearsal on suicide prevention gatekeeper skills.

PubMed

Cross, Wendi F; Seaburn, David; Gibbs, Danette; Schmeelk-Cone, Karen; White, Ann Marie; Caine, Eric D

2011-08-01

Suicide is the third leading cause of death among 10-24-year-olds and the target of school-based prevention efforts. Gatekeeper training, a broadly disseminated prevention strategy, has been found to enhance participant knowledge and attitudes about intervening with distressed youth. Although the goal of training is the development of gatekeeper skills to intervene with at-risk youth, the impact on skills and use of training is less known. Brief gatekeeper training programs are largely educational and do not employ active learning strategies such as behavioral rehearsal through role play practice to assist skill development. In this study, we compare gatekeeper training as usual with training plus brief behavioral rehearsal (i.e., role play practice) on a variety of learning outcomes after training and at follow-up for 91 school staff and 56 parents in a school community. We found few differences between school staff and parent participants. Both training conditions resulted in enhanced knowledge and attitudes, and almost all participants spread gatekeeper training information to others in their network. Rigorous standardized patient and observational methods showed behavioral rehearsal with role play practice resulted in higher total gatekeeper skill scores immediately after training and at follow-up. Both conditions, however, showed decrements at follow-up. Strategies to strengthen and maintain gatekeeper skills over time are discussed.
The effects of situational obstacles and social support on suicide- prevention gatekeeper behaviors.

PubMed

Moore, J Taylor; Cigularov, Konstantin P; Chen, Peter Y; Martinez, Jeremy M; Hindman, Jarrod

2011-01-01

Although the effectiveness of suicide-prevention gatekeeper-training programs in improving knowledge, attitudes, and referral practices has been documented, their effects do not seem to be lasting. This study investigated situational obstacles at work that prevent suicide-prevention gatekeepers from engaging in suicide-prevention behavior and the role of social support in modifying the relationship between situational obstacles and suicide-prevention behaviors. 193 gatekeepers completed an online survey to rate the obstacles they had experienced at work since completing a gatekeeper-training program and the support received from coworkers, supervisors, and the organization. Participants also reported the frequency of suicide-prevention behaviors performed. The results indicated that both situational obstacles and social support predicted the number of suicide-prevention behaviors performed, as expected. There was also a trend that support from supervisors and the organization may alleviate the adverse effect of situational obstacles on suicide-prevention behavior. The cross-sectional nature of the study does not allow for directional, causal conclusions to be drawn. By understanding the roles of situational obstacles faced by trained gatekeepers at their work and the support they receive from supervisors and organizations, appropriate strategies can be identified and applied to facilitate gatekeeper performance.
Academic Role and Perceptions of Gatekeeping in Counselor Education

ERIC Educational Resources Information Center

Schuermann, Hope; Avent Harris, Janeé R.; Lloyd-Hazlett, Jessica

2018-01-01

Gatekeeping in counselor education is an ethical responsibility and professional best practice. The authors examined gatekeeping perceptions of 9 counselor educators, with equal representation of assistant professors, associate/full professors, and adjuncts/instructors/lecturers. The authors analyzed data using consensual qualitative research…
Maternal Gatekeeping: Antecedents and Consequences

ERIC Educational Resources Information Center

Gaunt, Ruth

2008-01-01

This study examined maternal gatekeeping, its background and psychological antecedents, and its consequences for paternal and maternal involvement in child care. In sum, 209 couples with 6- to 36-month-old children completed extensive questionnaires. Analyses revealed that various dimensions of gate-keeping were differentially associated with the…
Brief gatekeeper training for suicide prevention in an ethnic minority population: a controlled intervention.

PubMed

Teo, Alan R; Andrea, Sarah B; Sakakibara, Rae; Motohara, Satoko; Matthieu, Monica M; Fetters, Michael D

2016-07-07

Suicide is a critical public health problem around the globe. Asian populations are characterized by elevated suicide rates and a tendency to seek social support from family and friends over mental health professionals. Gatekeeper training programs have been developed to train frontline individuals in behaviors that assist at-risk individuals in obtaining mental health treatment. The purpose of this study is to assess the efficacy of a brief, multi-component gatekeeper intervention in promoting suicide prevention in a high-risk Asian community in the United States. We adapted an evidence-based gatekeeper training into a two-hour, multi-modal and interactive event for Japanese-Americans and related stakeholders. Then we evaluated the intervention compared to an attention control using mixed methods. A sample of 106 community members participated in the study. Intervention participants (n = 85) showed significant increases in all three types of intended gatekeeper behavior, all four measures of self-efficacy, and both measures of social norms relevant to suicide prevention, while the control group (n = 48) showed no significant improvements. Additional results showed significantly higher satisfaction and no adverse experiences associated with the gatekeeper training. The separate collection of qualitative data, and integration with the quantitative survey constructs confirmed and expanded understanding about the benefits of the intervention. A brief, multi-modal gatekeeper training is efficacious in promoting positive gatekeeper behaviors and self-efficacy for suicide prevention in an at-risk ethnic minority population of Japanese Americans.
Information Gatekeepers in California's Ethnic Communities. Final Report.

ERIC Educational Resources Information Center

Metoyer-Duran, Cheryl

This study examined the information seeking behavior of gatekeepers in five ethnolinguistic communities: American Indian, Chinese, Japanese, Korean, and Latino. Personal interviews were conducted with 129 gatekeepers and a conceptual information model was used to generate an analytical framework for presenting and discussing the data. The major…
Students' Perspectives on Gatekeeping in Counselor Education: A Case Study

ERIC Educational Resources Information Center

Foster, Jennifer M.; Leppma, Monica; Hutchinson, Tracy S.

2014-01-01

Through in-depth interviews, the authors examined 10 master's-level counseling students' perceptions of gatekeeping. Case analysis resulted in 3 major themes pertaining to the necessity of gatekeeping, vital components, and counseling student characteristics. Implications of the findings are also discussed.
Mother Knows Best? Inhibitory Maternal Gatekeeping, Psychological Control, and the Mother-Adolescent Relationship

ERIC Educational Resources Information Center

Holmes, Erin Kramer; Dunn, KayLee C.; Harper, James; Dyer, W. Justin; Day, Randal D.

2013-01-01

We used structural equation modeling to explore associations between inhibitory maternal gatekeeping attitudes, reports of inhibitory maternal gatekeeping behaviors, maternal psychological control, observed mother-adolescent warmth, and adolescent reports of maternal involvement. Our random stratified sample consisted of 315 mothers and their…
Toward a Political-Organizational Model of Gatekeeping: The Case of Elite Colleges.

ERIC Educational Resources Information Center

Karen, David

1990-01-01

Develops a gatekeeping theory by stepping inside the black box of Harvard university's admissions process. Stresses how political and organizational contexts influence selection (gatekeeping). Analyzes how student merit and social class-based factors mutually determine selection. Links an understanding of the organizational field with process…
From Informal Gatekeeper to Information Counselor: Emergence of a New Professional Role.

ERIC Educational Resources Information Center

Dosa, Marta; And Others

Borrowed from the literature of more than two decades ago--when it alluded to key communicators within organizations--the concept of "gatekeeper" is reintroduced in this report. The role of information counselors, who, like informal gatekeepers, take part in liaison activities, networking, advising, information filtering, transmitting,…
The Gatekeeping Imperative in Counselor Education Admission Protocols: The Criticality of Personal Qualities

ERIC Educational Resources Information Center

McCaughan, Ann M.; Hill, Nicole R.

2015-01-01

Admission procedures in counselor education have received little focus regarding their essential function in gatekeeping. By exploring current admission trends, specifically as they relate to the identification of preferred personal qualities, implications for development of more rigorous admission gatekeeping procedures will be addressed. A call…
Appropriate Targets for Search Advertising as Part of Online Gatekeeping for Suicide Prevention.

PubMed

Sueki, Hajime; Ito, Jiro

2018-05-01

Gatekeeper training is an effective suicide prevention strategy. However, the appropriate targets of online gatekeeping have not yet been clarified. We examined the association between the outcomes of online gatekeeping using the Internet and the characteristics of consultation service users. An advertisement to encourage the use of e-mail-based psychological consultation services among viewers was placed on web pages that showed the results of searches using suicide-related keywords. All e-mails received between October 2014 and December 2015 were replied to as part of gatekeeping, and the obtained data (responses to an online questionnaire and the content of the received e-mails) were analyzed. A total of 154 consultation service users were analyzed, 35.7% of whom were male. The median age range was 20-29 years. Online gatekeeping was significantly more likely to be successful when such users faced financial/daily life or workplace problems, or revealed their names (including online names). By contrast, the activity was more likely to be unsuccessful when it was impossible to assess the problems faced by consultation service users. It may be possible to increase the success rate of online gatekeeping by targeting individuals facing financial/daily life or workplace problems with marked tendencies for self-disclosure.
Identifying Gatekeepers in Online Learning Networks

ERIC Educational Resources Information Center

Gursakal, Necmi; Bozkurt, Aras

2017-01-01

The rise of the networked society has not only changed our perceptions but also the definitions, roles, processes and dynamics of online learning networks. From offline to online worlds, networks are everywhere and gatekeepers are an important entity in these networks. In this context, the purpose of this paper is to explore gatekeeping and…
Gatekeeper Training in Campus Suicide Prevention

ERIC Educational Resources Information Center

Wallack, Cory; Servaty-Seib, Heather L.; Taub, Deborah J.

2013-01-01

Gatekeeper training is one of the most commonly employed methods for identifying and intervening with at-risk students (Davidson and Locke, 2010). Within the context of campus suicide prevention, a gatekeeper is broadly defined as any individual who has the potential to come into contact with at-risk students (Davidson and Locke, 2010). Although…
Gatekeeping and Competency-Based Education: Developing Behaviorally Specific Remediation Policies

ERIC Educational Resources Information Center

Hylton, Mary E.; Manit, Jill; Messick-Svare, Gloria

2017-01-01

Gatekeeping has long been an integral component of what is now referred to as the Implicit Curriculum, or the context in which professional social work education occurs. Despite its long-standing role within social work education, gatekeeping elicits conflict for both individual faculty members and entire programs of social work education. Much of…
Light-Induced Acid Generation on a Gatekeeper for Smart Nitric Oxide Delivery.

PubMed

Choi, Hyung Woo; Kim, Jihoon; Kim, Jinhwan; Kim, Yonghwi; Song, Hyun Beom; Kim, Jeong Hun; Kim, Kimoon; Kim, Won Jong

2016-04-26

We report herein the design of a light-responsive gatekeeper for smart nitric oxide (NO) delivery. The gatekeeper is composed of a pH-jump reagent as an intermediary of stimulus and a calcium phosphate (CaP) coating as a shielding layer for NO release. The light irradiation and subsequent acid generation are used as triggers for uncapping the gatekeeper and releasing NO. The acids generated from a light-activated pH-jump agent loaded in the mesoporous nanoparticles accelerated the degradation of the CaP-coating layers on the nanoparticles, facilitating the light-responsive NO release from diazeniumdiolate by exposing a NO donor to physiological conditions. Using the combination of the pH-jump reagent and CaP coating, we successfully developed a light-responsive gatekeeper system for spatiotemporal-controlled NO delivery.
Student Engagement and Completion in Precalculus Precalculus Mega Section: Efficiently Assisting Student Engagement and Completion with Communications and Information Technology

ERIC Educational Resources Information Center

Brusi, Rima; Portnoy, Arturo; Toro, Nilsa

2013-01-01

The Precalculus Mega Section project was developed with the main purpose of improving the overall performance of the student body in Precalculus, an important gatekeeper course that affects student engagement and completion, with typical drop/failure rates of over 50 percent. Strategies such as integration of technology and additional practice…
Implementing an Audience-Specific Small-Group Gatekeeper Training Program to Respond to Suicide Risk among College Students: A Case Study

ERIC Educational Resources Information Center

Cimini, M. Dolores; Rivero, Estela M.; Bernier, Joseph E.; Stanley, Judith A.; Murray, Andrea D.; Anderson, Drew A.; Wright, Heidi R.; Bapat, Mona

2014-01-01

Objective: This case study evaluated the effectiveness of an audience-specific, single-session, small-group interactive gatekeeper training program conducted at a large northeastern public university. Participants: Participants were 335 faculty, staff, and students completing gatekeeper training programs tailored to their group needs. Methods:…
Food skills confidence and household gatekeepers' dietary practices.

PubMed

Burton, Melissa; Reid, Mike; Worsley, Anthony; Mavondo, Felix

2017-01-01

Household food gatekeepers have the potential to influence the food attitudes and behaviours of family members, as they are mainly responsible for food-related tasks in the home. The aim of this study was to determine the role of gatekeepers' confidence in food-related skills and nutrition knowledge on food practices in the home. An online survey was completed by 1059 Australian dietary gatekeepers selected from the Global Market Insite (GMI) research database. Participants responded to questions about food acquisition and preparation behaviours, the home eating environment, perceptions and attitudes towards food, and demographics. Two-step cluster analysis was used to identify groups based on confidence regarding food skills and nutrition knowledge. Chi-square tests and one-way ANOVAs were used to compare the groups on the dependent variables. Three groups were identified: low confidence, moderate confidence and high confidence. Gatekeepers in the highest confidence group were significantly more likely to report lower body mass index (BMI), and indicate higher importance of fresh food products, vegetable prominence in meals, product information use, meal planning, perceived behavioural control and overall diet satisfaction. Gatekeepers in the lowest confidence group were significantly more likely to indicate more perceived barriers to healthy eating, report more time constraints and more impulse purchasing practices, and higher convenience ingredient use. Other smaller associations were also found. Household food gatekeepers with high food skills confidence were more likely to engage in several healthy food practices, while those with low food skills confidence were more likely to engage in unhealthy food practices. Food education strategies aimed at building food-skills and nutrition knowledge will enable current and future gatekeepers to make healthier food decisions for themselves and for their families. Copyright Â© 2016 Elsevier Ltd. All rights reserved.

Factors Affecting Patient Satisfaction with Community Health Service under the Gatekeeper System: A Cross-sectional Study in Nanjing, China.

PubMed

Li, Wen Zhen; Gan, Yong; Zhou, Yan Feng; Chen, Ya Wen; Li, Jing; Kkandawire, Naomiem; Hu, Sai; Qiao, Yan; Lu, Zu Xun

2017-09-01

The gatekeeper policy has been implemented for approximately ten years on a pilot population in China. It is necessary to assess the satisfaction of patients utilizing community health service (CHS) under the gatekeeper system. Our study showed that the cognition of gatekeeper policy was associated with four dimensions including doctor-patient relationships, information and support, organization of care, and accessibility (P < 0.001). One or more factors such as gender and self-perceived health scores also affected their satisfaction. General practitioners must be prepared to focus on these aspects of information and support, organization of care, and accessibility as indicators of potential opportunities for improvement. Additionally, policymakers can improve patients' satisfaction with CHS by strengthening their awareness of the gatekeeper policy. Copyright © 2017 The Editorial Board of Biomedical and Environmental Sciences. Published by China CDC. All rights reserved.
Integrative Technologies and Knowledge Gatekeepers: Bridging the Gap between Epistemic Communities in the Case of Stem Cell Science

ERIC Educational Resources Information Center

Wink, Rudiger

2008-01-01

The article analyses the role of gatekeepers between regional and disciplinary innovation systems in stem cell research as a case of integrative technologies. Which kind of gatekeepers is needed and which function can be fulfilled, differs along the knowledge value chain. Empirical results are used to explain the rationality of stem cell policies…
The Impact of Experiential Exercises on Communication and Relational Skills in a Suicide Prevention Gatekeeper-Training Program for College Resident Advisors

ERIC Educational Resources Information Center

Pasco, Susan; Wallack, Cory; Sartin, Robert M.; Dayton, Rebecca

2012-01-01

Objective: In an effort to identify students at risk for suicide, many colleges are implementing suicide prevention training for campus gatekeepers. This study evaluated the efficacy of a 3-hour, experiential-based gatekeeper training that included an emphasis on enhancing communication skills and relational connection in addition to the didactic…
For Whose Eyes Only? The Gatekeeping of Sexual Images in the Field of Teen Sexuality

ERIC Educational Resources Information Center

Chittenden, Tara

2010-01-01

This article examines the ways in which gatekeepers shape the field of teen sexuality by controlling access to sexual images. I question who decides whether an image is "appropriate" for young adults and how such judgements shape the wider cultural field. The ways in which gatekeepers have attempted to shield teens from certain sexual images…
Randomized Trial of a Gatekeeper Program for Suicide Prevention: 1-year Impact on Secondary School Staff

PubMed Central

Wyman, Peter A.; Brown, C Hendricks; Inman, Jeff; Cross, Wendi; Schmeelk-Cone, Karen; Guo, Jing; Pena, Juan B.

2009-01-01

Gatekeeper-training programs, designed to increase identification and referral of suicidal individuals, are widespread but largely untested. A group-based randomized trial with 32 schools examined impact of QPR (Question, Persuade, Refer) training on a stratified random sample of 249 staff with one-year average follow-up. To test QPR impact, we introduced and contrasted two models of gatekeeper-training effects in a population: Gatekeeper Surveillance and Gatekeeper Communication. Intent-to-treat analyses showed that training increased self-reported knowledge (ES 0.41) and appraisals of efficacy (ES 1.22) and service access (ES 1.07). Training effects varied dramatically. Appraisals increased most for staff with lowest baseline appraisals, and suicide identification behaviors increased most for staff already communicating with students about suicide and distress. Consistent with the Communication model, increased knowledge and appraisals were not sufficient to increase suicide identification behaviors. Also consistent with the Communication model were results from 2,059 8th and 10th graders surveyed showing that fewer with prior suicide attempts endorsed talking to adults about distress. Skill training for staff serving as ‘natural-gatekeepers’ plus interventions that modify students’ help-seeking behaviors are recommended to supplement universal gatekeeper training. PMID:18229988
Condom Use Among Female Sex Workers in China: Role of Gatekeepers

PubMed Central

YANG, HONGMEI; LI, XIAOMING; STANTON, BONITA; FANG, XIAOYI; ZHAO, RAN; DONG, BAIQING; LIU, WEI; LIANG, SHAOLING; ZHOU, YUEJIAO; HONG, YAN

2007-01-01

Objective The objective of this study was to assess the potential role of gatekeepers of establishments in promoting condom use among female sex workers (FSWs) in China. Goals The goals of this study were to explore FSWs’ perceptions of gatekeeper attitudes and support for condom use, and to assess their association with FSWs’ practice, communication, intention, proper use, knowledge of correct use, and perceptions related to condom use. Study The authors conducted a cross-sectional study among 454 establishment-based FSWs in one Chinese county. Results Perceived gatekeeper support for condom use was low among FSWs. Perceived support was positively associated with condom use communication with sexual partners, condom use frequency and intention, but not associated with proper condom use among FSWs. Perceived support was significantly associated with most condom use-related perceptions (e.g., self-efficacy of condom use, barriers to condom use, and perceived peer condom use) among FSWs. Conclusions Healthcare professionals should work with gatekeepers to create a supportive local environment for condom use in sex work establishments. Gatekeepers need to clearly articulate their support for condom use to the FSWs. Training and skill acquisition regarding correct use of condoms among FSWs will be necessary. PMID:16118607
Efficacy of Adolescent Suicide Prevention E-Learning Modules for Gatekeepers: A Randomized Controlled Trial.

PubMed

Ghoncheh, Rezvan; Gould, Madelyn S; Twisk, Jos Wr; Kerkhof, Ad Jfm; Koot, Hans M

2016-01-29

Face-to-face gatekeeper training can be an effective strategy in the enhancement of gatekeepers' knowledge and self-efficacy in adolescent suicide prevention. However, barriers related to access (eg, time, resources) may hamper participation in face-to-face training sessions. The transition to a Web-based setting could address obstacles associated with face-to-face gatekeeper training. Although Web-based suicide prevention training targeting adolescents exists, so far no randomized controlled trials (RCTs) have been conducted to investigate their efficacy. This RCT study investigated the efficacy of a Web-based adolescent suicide prevention program entitled Mental Health Online, which aimed to improve the knowledge and self-confidence of gatekeepers working with adolescents (12-20 years old). The program consisted of 8 short e-learning modules each capturing an important aspect of the process of early recognition, guidance, and referral of suicidal adolescents, alongside additional information on the topic of (adolescent) suicide prevention. A total of 190 gatekeepers (ages 21 to 62 years) participated in this study and were randomized to either the experimental group or waitlist control group. The intervention was not masked. Participants from both groups completed 3 Web-based assessments (pretest, posttest, and 3-month follow-up). The outcome measures of this study were actual knowledge, and participants' ratings of perceived knowledge and perceived self-confidence using questionnaires developed specifically for this study. The actual knowledge, perceived knowledge, and perceived self-confidence of gatekeepers in the experimental group improved significantly compared to those in the waitlist control group at posttest, and the effects remained significant at 3-month follow-up. The overall effect sizes were 0.76, 1.20, and 1.02, respectively, across assessments. The findings of this study indicate that Web-based suicide prevention e-learning modules can be an effective educational method to enhance knowledge and self-confidence of gatekeepers with regard to adolescent suicide prevention. Gatekeepers with limited time and resources can benefit from the accessibility, simplicity, and flexibility of Web-based training. Netherlands Trial Register NTR3625; http://www.trialregister.nl/trialreg/admin/rctview.asp?TC=3625 (Archived by WebCite at http://www.webcitation.org/6eHvyRh6M).
What is the role and authority of gatekeepers in cluster randomized trials in health research?

PubMed Central

2012-01-01

This article is part of a series of papers examining ethical issues in cluster randomized trials (CRTs) in health research. In the introductory paper in this series, we set out six areas of inquiry that must be addressed if the CRT is to be set on a firm ethical foundation. This paper addresses the sixth of the questions posed, namely, what is the role and authority of gatekeepers in CRTs in health research? ‘Gatekeepers’ are individuals or bodies that represent the interests of cluster members, clusters, or organizations. The need for gatekeepers arose in response to the difficulties in obtaining informed consent because of cluster randomization, cluster-level interventions, and cluster size. In this paper, we call for a more restrictive understanding of the role and authority of gatekeepers. Previous papers in this series have provided solutions to the challenges posed by informed consent in CRTs without the need to invoke gatekeepers. We considered that consent to randomization is not required when cluster members are approached for consent at the earliest opportunity and before any study interventions or data-collection procedures have started. Further, when cluster-level interventions or cluster size means that obtaining informed consent is not possible, a waiver of consent may be appropriate. In this paper, we suggest that the role of gatekeepers in protecting individual interests in CRTs should be limited. Generally, gatekeepers do not have the authority to provide proxy consent for cluster members. When a municipality or other community has a legitimate political authority that is empowered to make such decisions, cluster permission may be appropriate; however, gatekeepers may usefully protect cluster interests in other ways. Cluster consultation may ensure that the CRT addresses local health needs, and is conducted in accord with local values and customs. Gatekeepers may also play an important role in protecting the interests of organizations, such as hospitals, nursing homes, general practices, and schools. In these settings, permission to access the organization relies on resource implications and adherence to institutional policies. PMID:22834691
"On the doctor's orders": A pilot study of the effects of website marketing for medical specialist providers under gatekeeping arrangements.

PubMed

Zwier, Sandra

2017-01-01

Websites from medical specialist providers are becoming increasingly marketing oriented, but there exists a paucity of empirical research on the effects. This experimental study explored effects of exposure to real websites from medical specialist providers among Dutch adults under physician gatekeeper arrangements. Exposure led to a stronger intention to seek treatment from the specialist provider and motivation to rely on the providers' claims. Weaker to absent effects were found for intention to question the physician gatekeeper's referral and this was chiefly motivated by the belief that "the doctor knows best." Implications for specialist provider marketing under gatekeeping arrangements are discussed.
Activation of tyrosine kinases by mutation of the gatekeeper threonine

PubMed Central

Azam, Mohammad; Seeliger, Markus A; Gray, Nathanael S; Kuriyan, John; Daley, George Q

2008-01-01

Protein kinases targeted by small-molecule inhibitors develop resistance through mutation of the ‘gatekeeper’ threonine residue of the active site. Here we show that the gatekeeper mutation in the cellular forms of c-ABL, c-SRC, platelet-derived growth factor receptor-α and -β, and epidermal growth factor receptor activates the kinase and promotes malignant transformation of BaF3 cells. Structural analysis reveals that a network of hydrophobic interactions—the hydrophobic spine—characteristic of the active kinase conformation is stabilized by the gatekeeper substitution. Substitution of glycine for the residues constituting the spine disrupts the hydrophobic connectivity and inactivates the kinase. Furthermore, a small-molecule inhibitor that maximizes complementarity with the dismantled spine (compound 14) inhibits the gatekeeper mutation of BCR-ABL-T315I. These results demonstrate that mutation of the gatekeeper threonine is a common mechanism of activation for tyrosine kinases and provide structural insights to guide the development of next-generation inhibitors. PMID:18794843
The impact of experiential exercises on communication and relational skills in a suicide prevention gatekeeper-training program for college resident advisors.

PubMed

Pasco, Susan; Wallack, Cory; Sartin, Robert M; Dayton, Rebecca

2012-01-01

In an effort to identify students at risk for suicide, many colleges are implementing suicide prevention training for campus gatekeepers. This study evaluated the efficacy of a 3-hour, experiential-based gatekeeper training that included an emphasis on enhancing communication skills and relational connection in addition to the didactic foci of standard gatekeeper training. Sixty-five college student resident advisors (RAs) were trained with Campus Connect. The training was dismantled to examine the specific contribution of experiential exercises on training outcomes. Compared to didactic training alone, following participation in experiential exercises RAs' training outcome scores exhibited additional improvement on the Suicide Intervention Response Inventory-2 and a 14-item self-report measure of self-efficacy for specific suicide- and crisis-related knowledge and skills. In gatekeeper training, experiential exercises emphasizing awareness and empathic responding and practice of these skills contribute to an improvement in crisis response skills above and beyond that of didactic training alone.
Mixture-based gatekeeping procedures in adaptive clinical trials.

PubMed

Kordzakhia, George; Dmitrienko, Alex; Ishida, Eiji

2018-01-01

Clinical trials with data-driven decision rules often pursue multiple clinical objectives such as the evaluation of several endpoints or several doses of an experimental treatment. These complex analysis strategies give rise to "multivariate" multiplicity problems with several components or sources of multiplicity. A general framework for defining gatekeeping procedures in clinical trials with adaptive multistage designs is proposed in this paper. The mixture method is applied to build a gatekeeping procedure at each stage and inferences at each decision point (interim or final analysis) are performed using the combination function approach. An advantage of utilizing the mixture method is that it enables powerful gatekeeping procedures applicable to a broad class of settings with complex logical relationships among the hypotheses of interest. Further, the combination function approach supports flexible data-driven decisions such as a decision to increase the sample size or remove a treatment arm. The paper concludes with a clinical trial example that illustrates the methodology by applying it to develop an adaptive two-stage design with a mixture-based gatekeeping procedure.
Gatekeeping versus direct-access when patient information matters.

PubMed

González, Paula

2010-06-01

We develop a principal-agent model in which the health authority acts as a principal for both a patient and a general practitioner (GP). The goal of the paper is to weigh the merits of gatekeeping versus non-gatekeeping approaches to health care when patient self-health information and patient pressure on GPs to provide referrals for specialized care are considered. We find that, when GPs incentives matter, a non-gatekeeping system is preferable only when (i) patient pressure to refer is sufficiently high and (ii) the quality of the patient's self-health information is neither highly inaccurate (in which case the patient's self-referral will be very inefficient) nor highly accurate (in which case the GP's agency problem will be very costly).
Rationally engineered flavin-dependent oxidase reveals steric control of dioxygen reduction.

PubMed

Zafred, Domen; Steiner, Barbara; Teufelberger, Andrea R; Hromic, Altijana; Karplus, P Andrew; Schofield, Christopher J; Wallner, Silvia; Macheroux, Peter

2015-08-01

The ability of flavoenzymes to reduce dioxygen varies greatly, and is controlled by the protein environment, which may cause either a rapid reaction (oxidases) or a sluggish reaction (dehydrogenases). Previously, a 'gatekeeper' amino acid residue was identified that controls the reactivity to dioxygen in proteins from the vanillyl alcohol oxidase superfamily of flavoenzymes. We have identified an alternative gatekeeper residue that similarly controls dioxygen reactivity in the grass pollen allergen Phl p 4, a member of this superfamily that has glucose dehydrogenase activity and the highest redox potential measured in a flavoenzyme. A substitution at the alternative gatekeeper site (I153V) transformed the enzyme into an efficient oxidase by increasing dioxygen reactivity by a factor of 60,000. An inverse exchange (V169I) in the structurally related berberine bridge enzyme (BBE) decreased its dioxygen reactivity by a factor of 500. Structural and biochemical characterization of these and additional variants showed that our model enzymes possess a cavity that binds an anion and resembles the 'oxyanion hole' in the proximity of the flavin ring. We showed also that steric control of access to this site is the most important parameter affecting dioxygen reactivity in BBE-like enzymes. Analysis of flavin-dependent oxidases from other superfamilies revealed similar structural features, suggesting that dioxygen reactivity may be governed by a common mechanistic principle. Structural data are available in PDB database under the accession numbers 4PVE, 4PVH, 4PVJ, 4PVK, 4PWB, 4PWC and 4PZF. © 2015 FEBS.
Who needs a gatekeeper? Patients' views of the role of the primary care physician.

PubMed

Gross, R; Tabenkin, H; Brammli-Greenberg, S

2000-06-01

The primary care physician serving as a 'gatekeeper' can make judicious decisions about the appropriate use of medical services, and thereby contribute to containing costs while improving the quality of care. However, in Israel, sick funds competing for members have not adopted this model for fear of endangering their competitive stance. The purpose of this study was to examine, for the first time, the stated preferences and actual behaviour of a national sample of members of the four Israeli sick funds regarding self-referral to specialists, and to identify the characteristics of patients who prefer the gatekeeper model. Data were derived from a national telephone survey carried out in 1997. A random representative sample of 1084 of all adult sick fund members were interviewed, with a response rate of 81%. Bivariate analysis was conducted using over all chi-square tests, and multivariate analysis was performed using logistic regression models. A third of all respondents prefer self-referral to a specialist, 40% prefer their family physician to act as gatekeeper and 19% prefer the physician to co-ordinate care but to refer themselves to a specialist. Independent variables predicting preference for the gatekeeper model are: living in the periphery, sick fund membership, low level of education, being male, fair or poor health status, having a permanent family physician and being satisfied with the professional level of the family physician. A significant correlation was found between practising self-referral and preference for self-referral. CONCLUSIONS.: The findings indicate the importance of surveying patients' attitudes as an input in policy formulation. The study identified specific population groups which prefer the gatekeeper model, and explored the advantages of a flexible model of gatekeeping.
How organizational context affects bioethical decision-making: pharmacists' management of gatekeeping processes in retail and hospital settings.

PubMed

Chiarello, Elizabeth

2013-12-01

Social science studies of bioethics demonstrate that ethics are highly contextual, functioning differently across local settings as actors make daily decisions "on the ground." Sociological studies that demonstrate the key role organizations play in shaping ethical decision-making have disproportionately focused on physicians and nurses working in hospital settings where they contend with life and death issues. This study broadens our understanding of the contexts of ethical decision-making by empirically examining understudied healthcare professionals - pharmacists - working in two organizational settings, retail and hospital, where they act as gatekeepers to regulated goods and services as they contend with ethical issues ranging from the serious to the mundane. This study asks: How do organizations shape pharmacists' identification, negotiation, and resolution of ethical challenges; in other words, how do organizations shape pharmacists' gatekeeping processes? Based on 95 semi-structured interviews with U.S. pharmacists practicing in retail and hospital pharmacies conducted between September 2009 and May 2011, this research finds that organizations influence ethical decision-making by shaping how pharmacists construct four gatekeeping processes: medical, legal, fiscal, and moral. Each gatekeeping process manifests differently across organizations due to how these settings structure inter-professional power dynamics, proximity to patients, and means of accessing information. Findings suggest new directions for theorizing about ethical decision-making in medical contexts by drawing attention to new ethical actors, new organizational settings, an expanded definition of ethical challenges, and a broader conceptualization of gatekeeping. Copyright © 2012 Elsevier Ltd. All rights reserved.
An algorithm of opinion leaders mining based on signed network

NASA Astrophysics Data System (ADS)

Cao, Linlin; Zheng, Mingchun; Zhang, Yuanyuan; Zhang, Fuming

2018-04-01

With the rapid development of mobile Internet, user gradually become the leader of social media, the abruptly rise of new media has changed the traditional information's dissemination pattern and regularity. There is new era significance of opinion leaders, gatekeepers in the classical theory of mass communication, and it has further expansion and extension to a certain extent. In the existing mining of opinion leaders, it is mainly from the research of network structure and user behavior without considering an important attribute: whether the user has a real impact. In this paper, we take the symbolic network as the research tool, by giving symbol which correspondingly represents support or oppose to the link about point of view relationship between users and combining traditional algorithms of mining with symbolism which can describe the change of view between users, we will get the opinion leader who has real impact on users, then the result is more accurate and effective.
Suicide prevention through online gatekeeping using search advertising techniques: a feasibility study.

PubMed

Sueki, Hajime; Ito, Jiro

2015-01-01

Nurturing gatekeepers is an effective suicide prevention strategy. Internet-based methods to screen those at high risk of suicide have been developed in recent years but have not been used for online gatekeeping. A preliminary study was conducted to examine the feasibility and effects of online gatekeeping. Advertisements to promote e-mail psychological consultation service use among Internet users were placed on web pages identified by searches using suicide-related keywords. We replied to all emails received between July and December 2013 and analyzed their contents. A total of 139 consultation service users were analyzed. The mean age was 23.8 years (SD = 9.7), and female users accounted for 80% of the sample. Suicidal ideation was present in 74.1%, and 12.2% had a history of suicide attempts. After consultation, positive changes in mood were observed in 10.8%, 16.5% showed intentions to seek help from new supporters, and 10.1% of all 139 users actually took help-seeking actions. Online gatekeeping to prevent suicide by placing advertisements on web search pages to promote consultation service use among Internet users with suicidal ideation may be feasible.
Conserved nonsense-prone CpG sites in apoptosis-regulatory genes: conditional stop signs on the road to cell death.

PubMed

Zhao, Yongzhong; Epstein, Richard J

2013-01-01

Methylation-prone CpG dinucleotides are strongly conserved in the germline, yet are also predisposed to somatic mutation. Here we quantify the relationship between germline codon mutability and somatic carcinogenesis by comparing usage of the nonsense-prone CGA (→TGA) codons in gene groups that differ in apoptotic function; to this end, suppressor genes were subclassified as either apoptotic (gatekeepers) or repair (caretakers). Mutations affecting CGA codons in sporadic tumors proved to be highly asymmetric. Moreover, nonsense mutations were 3-fold more likely to affect gatekeepers than caretakers. In addition, intragenic CGA clustering nonrandomly affected functionally critical regions of gatekeepers. We conclude that human gatekeeper suppressor genes are enriched for nonsense-prone codons, and submit that this germline vulnerability to tumors could reflect in utero selection for a methylation-dependent capability to short-circuit environmental insults that otherwise trigger apoptosis and fetal loss.
A multilevel analysis of gatekeeper characteristics and consistent condom use among establishment-based female sex workers in Guangxi, China.

PubMed

Li, Qing; Li, Xiaoming; Stanton, Bonita; Fang, Xiaoyi; Zhao, Ran

2010-11-01

Multilevel analytical techniques are being applied in condom use research to ensure the validity of investigation on environmental/structural influences and clustered data from venue-based sampling. The literature contains reports of consistent associations between perceived gatekeeper support and condom use among entertainment establishment-based female sex workers (FSWs) in Guangxi, China. However, the clustering inherent in the data (FSWs being clustered within establishment) has not been accounted in most of the analyses. We used multilevel analyses to examine perceived features of gatekeepers and individual correlates of consistent condom use among FSWs and to validate the findings in the existing literature. We analyzed cross-sectional data from 318 FSWs from 29 entertainment establishments in Guangxi, China in 2004, with a minimum of 5 FSWs per establishment. The Hierarchical Linear Models program with Laplace estimation was used to estimate the parameters in models containing random effects and binary outcomes. About 11.6% of women reported consistent condom use with clients. The intraclass correlation coefficient indicated 18.5% of the variance in condom use could be attributed to their similarity between FSWs within the same establishments. Women's perceived gatekeeper support and education remained positively associated with condom use (P < 0.05), after controlling for other individual characteristics and clustering. After adjusting for data clustering, perceived gatekeeper support remains associated with consistent condom use with clients among FSWs in China. The results imply that combined interventions to intervene both gatekeepers and individual FSW may effectively promote consistent condom use.

Gatekeeper training for suicide prevention in First Nations community members: a randomized controlled trial.

PubMed

Sareen, Jitender; Isaak, Corinne; Bolton, Shay-Lee; Enns, Murray W; Elias, Brenda; Deane, Frank; Munro, Garry; Stein, Murray B; Chateau, Dan; Gould, Madelyn; Katz, Laurence Y

2013-10-01

Gatekeeper training aims to train people to recognize and identify those who are at risk for suicide and assist them in getting care. Applied Suicide Intervention Skills Training (ASIST), a form of gatekeeper training, has been implemented around the world without a controlled evaluation. We hypothesized that participants in 2 days of ASIST gatekeeper training would have increased knowledge and preparedness to help people with suicidal ideation in comparison to participants who received a 2-day Resilience Retreat that did not focus on suicide awareness and intervention skills (control condition). First Nations on reserve people in Northwestern Manitoba, aged 16 years and older, were recruited and randomized to two arms of the study. Self-reported measures were collected at three time points-immediately pre-, immediately post-, and 6 months post intervention. The primary outcome was the Suicide Intervention Response Inventory, a validated scale that assesses the capacity for individuals to intervene with suicidal behavior. Secondary outcomes included self-reported preparedness measures and gatekeeper behaviors. In comparison with the Resilience Retreat (n = 24), ASIST training (n = 31) was not associated with a significant impact on all outcomes of the study based on intention-to-treat analysis. There was a trend toward an increase in suicidal ideation among those who participated in the ASIST in comparison to those who were in the Resilience Retreat. The lack of efficacy of ASIST in a First Nations on-reserve sample is concerning in the context of widespread policies in Canada on the use of gatekeeper training in suicide prevention. © 2013 Wiley Periodicals, Inc.
A Multilevel Analysis of Gatekeeper Characteristics and Consistent Condom Use Among Establishment-Based Female Sex Workers in Guangxi, China

PubMed Central

Li, Qing; Li, Xiaoming; Stanton, Bonita; Fang, Xiaoyi; Zhao, Ran

2010-01-01

Background Multilevel analytical techniques are being applied in condom use research to ensure the validity of investigation on environmental/structural influences and clustered data from venue-based sampling. The literature contains reports of consistent associations between perceived gatekeeper support and condom use among entertainments establishment-based female sex workers (FSWs) in Guangxi, China. However, the clustering inherent in the data (FSWs being clustered within establishment) has not been accounted in most of the analyses. We used multilevel analyses to examine perceived features of gatekeepers and individual correlates of consistent condom use among FSWs and to validate the findings in the existing literature. Methods We analyzed cross-sectional data from 318 FSWs from 29 entertainment establishments in Guangxi, China in 2004, with a minimum of 5 FSWs per establishment. The Hierarchical Linear Models program with Laplace estimation was used to estimate the parameters in models containing random effects and binary outcomes. Results About 11.6% of women reported consistent condom use with clients. The intraclass correlation coefficient indicated 18.5% of the variance in condom use could be attributed to their similarity between FSWs within the same establishments. Women’s perceived gatekeeper support and education remained positively associated with condom use (P < 0.05), after controlling for other individual characteristics and clustering. Conclusions After adjusting for data clustering, perceived gatekeeper support remains associated with consistent condom use with clients among FSWs in China. The results imply that combined interventions to intervene both gatekeepers and individual FSW may effectively promote consistent condom use. PMID:20539262
Primary care, financing and gatekeeping in western Europe.

PubMed

Gérvas, J; Pérez Fernández, M; Starfield, B H

1994-09-01

Primary care in western Europe is delivered by general practitioners (GPs) but their role within the overall health system is poorly understood. The aim of this article is to present an overview of the characteristics of general practice in the context of health systems and to describe their variability and interrelationships. Data were obtained from two main sources: publications of official organizations and EC research projects. The characteristics of general practice are described and analysed with regard to three features: mode of payment, gatekeeper function and practice organization and workload. Despite their focus on general practice as the cornerstone of the health system, western European countries differ considerably in the major characteristics of primary care. There is variability in the ratio of GPs to population and in the extent to which patients relate to individual physicians. Although all countries have universal health insurance, the mode of payment of GPs differs. In some countries, the gatekeeper function of general practice is more highly developed and the use of specialist services varies accordingly. Practice characteristics such as workload, length of consultation, ordering of tests and reappointments also vary with differences in payment and gatekeeping arrangements. In particular, fee-for-service was associated with weaker physician-patient relationships, reduced attractiveness of general practice, more home visiting and longer consultations. Strong gatekeeping arrangements are not incompatible with high public satisfaction and are associated with lower visit rates. However, strong gatekeeping is not characteristic of fee-for-service arrangements. These findings suggest a need for more concerted research that could inform policy decisions concerning primary care in the USA as well as in Europe.
Efficacy of Adolescent Suicide Prevention E-Learning Modules for Gatekeepers: A Randomized Controlled Trial

PubMed Central

Gould, Madelyn S; Twisk, Jos WR; Kerkhof, Ad JFM; Koot, Hans M

2016-01-01

Background Face-to-face gatekeeper training can be an effective strategy in the enhancement of gatekeepers’ knowledge and self-efficacy in adolescent suicide prevention. However, barriers related to access (eg, time, resources) may hamper participation in face-to-face training sessions. The transition to a Web-based setting could address obstacles associated with face-to-face gatekeeper training. Although Web-based suicide prevention training targeting adolescents exists, so far no randomized controlled trials (RCTs) have been conducted to investigate their efficacy. Objective This RCT study investigated the efficacy of a Web-based adolescent suicide prevention program entitled Mental Health Online, which aimed to improve the knowledge and self-confidence of gatekeepers working with adolescents (12-20 years old). The program consisted of 8 short e-learning modules each capturing an important aspect of the process of early recognition, guidance, and referral of suicidal adolescents, alongside additional information on the topic of (adolescent) suicide prevention. Methods A total of 190 gatekeepers (ages 21 to 62 years) participated in this study and were randomized to either the experimental group or waitlist control group. The intervention was not masked. Participants from both groups completed 3 Web-based assessments (pretest, posttest, and 3-month follow-up). The outcome measures of this study were actual knowledge, and participants’ ratings of perceived knowledge and perceived self-confidence using questionnaires developed specifically for this study. Results The actual knowledge, perceived knowledge, and perceived self-confidence of gatekeepers in the experimental group improved significantly compared to those in the waitlist control group at posttest, and the effects remained significant at 3-month follow-up. The overall effect sizes were 0.76, 1.20, and 1.02, respectively, across assessments. Conclusions The findings of this study indicate that Web-based suicide prevention e-learning modules can be an effective educational method to enhance knowledge and self-confidence of gatekeepers with regard to adolescent suicide prevention. Gatekeepers with limited time and resources can benefit from the accessibility, simplicity, and flexibility of Web-based training. Trial Registration Netherlands Trial Register NTR3625; http://www.trialregister.nl/trialreg/admin/rctview.asp?TC=3625 (Archived by WebCite at http://www.webcitation.org/6eHvyRh6M) PMID:26825006
The Ruler Protein EscP of the Enteropathogenic Escherichia coli Type III Secretion System Is Involved in Calcium Sensing and Secretion Hierarchy Regulation by Interacting with the Gatekeeper Protein SepL

PubMed Central

Shaulov, Lihi; Gershberg, Jenia; Deng, Wanyin; Finlay, B. Brett

2017-01-01

ABSTRACT The type III secretion system (T3SS) is a multiprotein complex that plays a central role in the virulence of many Gram-negative bacterial pathogens. To ensure that effector proteins are efficiently translocated into the host cell, bacteria must be able to sense their contact with the host cell. In this study, we found that EscP, which was previously shown to function as the ruler protein of the enteropathogenic Escherichia coli T3SS, is also involved in the switch from the secretion of translocator proteins to the secretion of effector proteins. In addition, we demonstrated that EscP can interact with the gatekeeper protein SepL and that the EscP-SepL complex dissociates upon a calcium concentration drop. We suggest a model in which bacterial contact with the host cell is accompanied by a drop in the calcium concentration that causes SepL-EscP complex dissociation and triggers the secretion of effector proteins. PMID:28049143
Husband Gatekeeping in Childbirth.

ERIC Educational Resources Information Center

Block, Carolyn R.; And Others

1981-01-01

Interviews with new mothers document the husband's role as gatekeeper in his wife's preparing for and coping with childbirth. Social class, race, family stage, and the husband-wife relationship explain about 40 percent of the variance in whether husbands choose to prepare for childbirth. (Author)
Take the Reins on Model Quality with ModelCHECK and Gatekeeper

NASA Technical Reports Server (NTRS)

Jones, Corey

2012-01-01

Model quality and consistency has been an issue for us due to the diverse experience level and imaginative modeling techniques of our users. Fortunately, setting up ModelCHECK and Gatekeeper to enforce our best practices has helped greatly, but it wasn't easy. There were many challenges associated with setting up ModelCHECK and Gatekeeper including: limited documentation, restrictions within ModelCHECK, and resistance from end users. However, we consider ours a success story. In this presentation we will describe how we overcame these obstacles and present some of the details of how we configured them to work for us.
Effectiveness of suicide prevention gatekeeper-training for university administrative staff in Japan.

PubMed

Hashimoto, Naoki; Suzuki, Yuriko; Kato, Takahiro A; Fujisawa, Daisuke; Sato, Ryoko; Aoyama-Uehara, Kumi; Fukasawa, Maiko; Asakura, Satoshi; Kusumi, Ichiro; Otsuka, Kotaro

2016-01-01

Suicide is a leading cause of death among Japanese college and university students. Gatekeeper-training programs have been shown to improve detection and referral of individuals who are at risk of suicide by training non-mental-health professional persons. However, no studies have investigated the effectiveness of such programs in university settings in Japan. The aim of this study was to investigate the effectiveness of the gatekeeper-training program for administrative staff in Japanese universities. We developed a 2.5-h gatekeeper-training program based on the Mental Health First Aid program, which was originally developed for the general public. Seventy-six administrative staff at Hokkaido University participated in the program. Competence and confidence in managing suicide intervention, behavioral intention as a gatekeeper and attitude while handling suicidal students were measured by a self-reported questionnaire before, immediately after and a month after the program. We found a significant improvement in competence in the management of suicidal students. We also found improvements in confidence in management of suicidal students and behavioral intention as a gatekeeper after training, though questionnaires for those secondary outcomes were not validated. These improvements continued for a month. About 95% of the participants rated the program as useful or very useful and one-third of the participants had one or more chances to utilize their skills within a month. The current results suggest the positive effects of the training program in university settings in Japan. Future evaluation that includes comparison with standard didactic trainings and an assessment of long-term effectiveness are warranted. © 2015 The Authors. Psychiatry and Clinical Neurosciences © 2015 Japanese Society of Psychiatry and Neurology.
Gatekeepers for Pragmatic Clinical Trials

PubMed Central

Whicher, Danielle M.; Miller, Jennifer E.; Dunham, Kelly M.; Joffe, Steven

2015-01-01

To successfully implement a pragmatic clinical trial, investigators need access to numerous resources, including financial support, institutional infrastructure (e.g., clinics, facilities, staff), eligible patients, and patient data. Gatekeepers are people or entities who have the ability to allow or deny access to the resources required to support the conduct of clinical research. Based on this definition, gatekeepers relevant to the United States clinical research enterprise include research sponsors, regulatory agencies, payers, health system and other organizational leadership, research team leadership, human research protections programs, advocacy and community groups, and clinicians. This manuscript provides a framework to help guide gatekeepers’ decision-making related to the use of resources for pragmatic clinical trials. These include (1) concern for the interests of individuals, groups, and communities affected by the gatekeepers’ decisions, including protection from harm and maximization of benefits, (2) advancement of organizational mission and values, and (3) stewardship of financial, human, and other organizational resources. Separate from these ethical considerations, gatekeepers’ actions will be guided by relevant federal, state, and local regulations. This framework also suggests that to further enhance the legitimacy of their decision-making, gatekeepers should adopt transparent processes that engage relevant stakeholders when feasible and appropriate. We apply this framework to the set of gatekeepers responsible for making decisions about resources necessary for pragmatic clinical trials in the United States, describing the relevance of the criteria in different situations and pointing out where conflicts among the criteria and relevant regulations may affect decision-making. Recognition of the complex set of considerations that should inform decision-making will guide gatekeepers in making justifiable choices regarding the use of limited and valuable resources. PMID:26374683
Knowing Asia: Creative Policy Translation in an Australian School Setting

ERIC Educational Resources Information Center

Salter, Peta

2014-01-01

Policy implementation at school level is often recognised as transformative enactment. Positioning school leaders as gatekeepers in this enactment is limiting. This study of one Australian school explores the complex contextualised agency of school leaders showing that their role, far more than gatekeeping, can be enabling and transformative.…
The Affective Gatekeeper: A Synthesis of Perspectives on Creativity.

ERIC Educational Resources Information Center

Bagley, Dan S., III

1979-01-01

The article presents research reports on the nature of creativity, including such elements as its characteristics; the function of the affective gatekeeper (which filters the "reality" perceived by each individual); the constructs of perception; and the functions of role playing, altered states of consciousness, and fantasy. (PHR)
Randomized Trial of Suicide Gatekeeper Training for Social Work Students

ERIC Educational Resources Information Center

Jacobson, Jodi M.; Osteen, Phillip J.; Sharpe, Tanya L.; Pastoor, Jennifer B.

2012-01-01

Problem: Education and research on social work's role in preventing client suicide is limited. Method: Seventy advanced master of social work students were randomly assigned to either the training group (Question, Persuade, and Referral suicide gatekeeper training) or the control group. Outcomes measured over time included suicide knowledge,…
The Gatekeeping Impulse and Professor X: An Exploration

ERIC Educational Resources Information Center

Sonnenmoser, Richard

2009-01-01

College and university instructors who assess student writing, including but not limited to teachers of first-year composition, sometimes keep the gate. Gatekeeping by writing instructors is an activity directly related to grading practices and, in many cases, to grading practices which emphasize formal, mechanical, usually sentence-level choices…
Gatekeeper Training for Youth Workers

ERIC Educational Resources Information Center

Cartmill, Tania; Deane, Frank; Wilson, Coralie

2009-01-01

Adults who act as gatekeepers for young people may have the same barriers to help-seeking for mental health issues as young people. This study investigated the personal help-seeking practices of 47 Australian youth workers prior to and after a training workshop on youth mental health issues. Pre-post workshop evaluation revealed some increases in…
The Influence of Suicide Prevention Gatekeeper Training on Resident Assistants' Mental Health

ERIC Educational Resources Information Center

Becker, Martin A. Swanbrow; Drum, David J.

2015-01-01

This study explored the mental health influence on resident assistants associated with their training in suicide prevention and their subsequent role as campus mental health gatekeepers. Despite considerable prior personal experience with their own suicidal thinking as well as with others who have thoughts of suicide, a multiple regression…
Ambivalences: Voices of Indonesian Academic Discourse Gatekeepers

ERIC Educational Resources Information Center

Basthomi, Yazid

2012-01-01

This article presents voices of academic discourse gatekeepers in the Indonesian context. It reports on results of an attempt to re-read (re-analyze and re-interpret) the transcripts of interviews with Indonesian journal editors/reviewers in the area of English Language Teaching (ELT). The interviews were made with five editors/reviewers of two…
Gatekeeping in Counselor Education: Experiences of Terminating Students for Nonacademic Concerns

ERIC Educational Resources Information Center

Wissel, Adriana M.

2011-01-01

Counselor Educators are required by both the American Counseling Association Code of Ethics (2009) as well as the Council for Accreditation of Counseling & Counseling Related Programs (2010) to serve as gatekeepers to the counseling profession. In this role, counselor educators ensure the safety of future clients and the counseling profession,…
Project M.O.M.--Mothers & Others & MyPyramid

ERIC Educational Resources Information Center

Wansink, Brian

2008-01-01

In today's dynamic and complex family structures, sometimes the nutritional gatekeeper is a stay-at-home dad, grandparent, housekeeper, or older sibling. Yet, despite a record level of women in the workforce and high educational achievement, the responsibility of being a nutrition gatekeeper still mainly falls on mothers. It is not equitable, it…
The Impact of Gatekeeper Training for Suicide Prevention on University Resident Assistants

ERIC Educational Resources Information Center

Taub, Deborah J.; Servaty-Seib, Heather L.; Miles, Nathan; Lee, Ji-Yeon; Wachter Morris, Carrie A.; Prieto-Welch, Susan L.; Werden, Donald

2013-01-01

Resident assistants (RAs) can serve as important suicide prevention gatekeepers. The purpose of the study was to determine if training improved RAs' crisis communications skills and suicide-related knowledge and to determine if the knowledge elements predicted crisis communications skills. New RAs showed significant improvement in all areas from…
Expanding Capacity for Suicide Prevention: The ALIVE @ Purdue Train-the-Trainers Program

ERIC Educational Resources Information Center

Wachter Morris, Carrie A.; Taub, Deborah J.; Servaty-Seib, Heather L.; Lee, Ji-Yeon; Miles, Nathan; Werden, Donald; Prieto-Welch, Susan L.

2015-01-01

Suicide is the second leading cause of death among college students. One effective strategy for suicide prevention is gatekeeper training. Gatekeeper training has been described as a prevention strategy that improves detection and referral of at-risk individuals. Purdue recognized that only some of the resident assistants (RAs) were receiving this…

Counselor Educators' Experiences of Gatekeeping in Online Master's-Level Counseling Programs

ERIC Educational Resources Information Center

Gilbert, Amy L.

2014-01-01

Counselor educators protect public welfare and serve as gatekeepers for the counseling profession by ensuring that counselors-in-training who do not meet professional standards of counseling competence are remediated or prevented from entering the counseling field. Prior to this study, no researchers had examined the unique aspects of gatekeeping…
Marital Problems, Maternal Gatekeeping Attitudes, and Father-Child Relationships in Adolescence

ERIC Educational Resources Information Center

Stevenson, Matthew M.; Fabricius, William V.; Cookston, Jeffrey T.; Parke, Ross D.; Coltrane, Scott; Braver, Sanford L.; Saenz, Delia S.

2014-01-01

We evaluated maternal gatekeeping attitudes as a mediator of the relation between marital problems and father-child relationships in 3 waves when children were in Grades 7-10. We assessed each parent's contribution to the marital problems experienced by the couple. Findings from mediational and cross-lagged structural equation models revealed that…
Gatekeeping: Why Shouldn't We Be Ambivalent?

ERIC Educational Resources Information Center

Sowbel, Lynda R.

2012-01-01

An increase of 88% in programs from 1990 through 2004, low GRE scores, low entry- level wages, declining pass rates in licensing tests, and an increase in ethical violations reported all support the contention that there are higher enrollment rates and decreased gatekeeping selectivity in today's graduate MSW programs. This article discusses four…
[Pharmacist as gatekeeper: combating medication abuse and dependence].

PubMed

Shimane, Takuya

2013-01-01

The nonmedical use of medications, including psychotropic drugs, is a growing health problem in Japan. According to a nationwide survey of mental hospitals, the proportion of patients with sedative (mainly benzodiazepine)-related disorders has more than doubled over the last decade. An association between psychotropic drug overdose and suicide risk has also been reported. Furthermore, over-the-counter drug abuse is still a serious problem in Japan. In recent years, pharmacists have been expected to act as gatekeepers, making timely identifications of suicide risk or substance abuse and directing these individuals to appropriate medical care facilities. In August 2012, the revised Comprehensive Suicide Measures Act identified pharmacists as one professional group that should act as gatekeepers. This article begins by reviewing the fundamental terms involved in understanding the nonmedical use of medications, including abuse, dependence, and intoxication. The current situation of substance abuse and dependence is then introduced through a summary of several epidemiological surveys conducted in Japan. Finally, the role of pharmacists as gatekeepers in preventing substance abuse and dependence on medications is discussed.
The need for a culturally-tailored gatekeeper training intervention program in preventing suicide among Indigenous peoples: a systematic review.

PubMed

Nasir, Bushra Farah; Hides, Leanne; Kisely, Steve; Ranmuthugala, Geetha; Nicholson, Geoffrey C; Black, Emma; Gill, Neeraj; Kondalsamy-Chennakesavan, Srinivas; Toombs, Maree

2016-10-21

Suicide is a leading cause of death among Indigenous youth worldwide. The aim of this literature review was to determine the cultural appropriateness and identify evidence for the effectiveness of current gatekeeper suicide prevention training programs within the international Indigenous community. Using a systematic strategy, relevant databases and targeted resources were searched using the following terms: 'suicide', 'gatekeeper', 'training', 'suicide prevention training', 'suicide intervention training' and 'Indigenous'. Other internationally relevant descriptors for the keyword "Indigenous" (e.g. "Maori", "First Nations", "Native American", "Inuit", "Metis" and "Aboriginal") were also used. Six articles, comprising five studies, met criteria for inclusion; two Australian, two from USA and one Canadian. While pre and post follow up studies reported positive outcomes, this was not confirmed in the single randomised controlled trial identified. However, the randomised controlled trial may have been underpowered and contained participants who were at higher risk of suicide pre-training. Uncontrolled evidence suggests that gatekeeper training may be a promising suicide intervention in Indigenous communities but needs to be culturally tailored to the target population. Further RCT evidence is required.
DFG-out Mode of Inhibition by an Irreversible Type-1 Inhibitor Capable of Overcoming Gate-Keeper Mutations in FGF Receptors

PubMed Central

2015-01-01

Drug-resistance acquisition through kinase gate-keeper mutations is a major hurdle in the clinic. Here, we determined the first crystal structures of the human FGFR4 kinase domain (FGFR4K) alone and complexed with ponatinib, a promiscuous type-2 (DFG-out) kinase inhibitor, and an oncogenic FGFR4K harboring the V550L gate-keeper mutation bound to FIIN-2, a new type-1 irreversible inhibitor. Remarkably, like ponatinib, FIIN-2 also binds in the DFG-out mode despite lacking a functional group necessary to occupy the pocket vacated upon the DFG-out flip. Structural analysis reveals that the covalent bond between FIIN-2 and a cysteine, uniquely present in the glycine-rich loop of FGFR kinases, facilitates the DFG-out conformation, which together with the internal flexibility of FIIN-2 enables FIIN-2 to avoid the steric clash with the gate-keeper mutation that causes the ponatinib resistance. The structural data provide a blueprint for the development of next generation anticancer inhibitors through combining the salient inhibitory mechanisms of ponatinib and FIIN-2. PMID:25317566
[Do gatekeeping programs increase equality of health care in Germany? A comparison of the health care situation of participants and nonparticipants].

PubMed

Schnitzer, S; Balke, K; Walter, A; Litschel, A; Kuhlmey, A

2011-08-01

This article compares the health care situation of participants in programs of general practitioner-centered health care (gatekeeping) in Germany (participants) with that of statutory health insurance holders who are not participating in such programs (nonparticipants). Because a key objective of the general practitioner model is to reduce the number of visits to specialists, the article also examines factors influencing frequent utilization of specialists in both groups. The analysis draws on a survey conducted by the National Association of Statutory Health Insurance Physicians (Kassenärztliche Bundesvereinigung, 2010) based on a sample representative of the German population. In this context, 5,232 holders of statutory health insurance aged between 18 and 79 years were interviewed on health care policy issues. The results show that regulating the utilization of specialists through the gatekeeping function of general practitioners succeeds in facilitating similar utilization rates across educational levels, between cities and towns, and between men and women. Thus, gatekeeping programs contribute to the reduction of health care inequalities.
How does gatekeeper training improve suicide prevention for elderly people in nursing homes? A controlled study in 24 centres.

PubMed

Chauliac, N; Brochard, N; Payet, C; Duclos, A; Terra, J-L

2016-09-01

The death rate due to suicide in elderly people is particularly high. As part of suicide selective prevention measures for at-risk populations, the WHO recommends training "gatekeepers". In order to assess the impact of gatekeeper training for members of staff, we carried out a controlled quasi-experimental study over the course of one year, comparing 12 nursing homes where at least 30% of the staff had undergone gatekeeper training with 12 nursing homes without trained staff. We collected data about the residents considered to be suicidal, their management further to being identified, as well as measures taken at nursing home level to prevent suicide. The two nursing home groups did not present significantly different characteristics. In the nursing homes with trained staff, the staff were deemed to be better prepared to approach suicidal individuals. The detection of suicidal residents relied more on the whole staff and less on the psychologist alone when compared to nursing homes without trained staff. A significantly larger number of measures were taken to manage suicidal residents in the trained nursing homes. Suicidal residents were more frequently referred to the psychologist. Trained nursing homes put in place significantly more suicide prevention measures at an institutional level. Having trained gatekeepers has an impact not only for the trained individuals but also for the whole institution where they work, both in terms of managing suicidal residents and routine suicide prevention measures. Copyright © 2016 Elsevier Masson SAS. All rights reserved.
Community Colleges as Gateways and Gatekeepers: Moving beyond the Access "Saga" toward Outcome Equity

ERIC Educational Resources Information Center

Dowd, Alicia C.

2007-01-01

Community colleges are essential--though often overlooked--institutions of higher education. In this essay, Alicia C. Dowd draws attention to the challenges facing community colleges as they seek to balance their roles as both gateways and gatekeepers with their multiple missions, which include meeting the diverse needs of students at the…
Does a Gatekeeper Suicide Prevention Program Work in a School Setting? Evaluating Training Outcome and Moderators of Effectiveness

ERIC Educational Resources Information Center

Tompkins, Tanya L.; Witt, Jody; Abraibesh, Nadia

2009-01-01

The current study sought to evaluate the suicide prevention gatekeeper training program QPR (Question, Persuade, and Refer) among school personnel using a non-equivalent control group design. Substantial gains were demonstrated from pre- to post-test for attitudes, knowledge, and beliefs regarding suicide and suicide prevention. Exploratory…
Understanding the Perceptions of Network Gatekeepers on Bandwidth and Online Video Streams in Ahmadu Bello University, Nigeria

ERIC Educational Resources Information Center

Odigie, Imoisili Ojeime; Gbaje, Ezra Shiloba

2017-01-01

Online video streaming is a learning technology used in today's world and reliant on the availability of bandwidth. This research study sought to understand the perceptions of network gatekeepers about bandwidth and online video streams in Ahmadu Bello University, Nigeria. To achieve this, the interpretive paradigm and the Network Gatekeeping…
The Role of Gatekeepers in the Asbestos Awareness Campaign.

ERIC Educational Resources Information Center

Freimuth, Vicki S.; Van Nevel, J. Paul

The role of news media as gatekeepers controlling the flow of information that the public receives was explored during the 1978 Asbestos Awareness campaign conducted by the Department of Health, Education, and Welfare (HEW). In an effort to inform high risk workers and the general public about the health hazards associated with asbestos exposure,…
Validation Study of a Gatekeeping Attitude Index for Social Work Education

ERIC Educational Resources Information Center

Tam, Dora M. Y.; Coleman, Heather

2011-01-01

This article reports on a study designed to validate the Gatekeeping Attitude Index, a 14-item Likert scaling index. The authors collected data from a convenience sample of social work field instructors (N = 188) with a response rate of 74.0%. Construct validation by exploratory factor analysis identified a 2-factor solution on the index after…
An Evaluation of a Unique Gatekeeper Training for Suicide Prevention of College Students: Demonstrating Effective Partnering within Student Affairs

ERIC Educational Resources Information Center

House, Lisa A.; Lynch, Joseph F.; Bane, Mary

2013-01-01

For college students, suicide is the second leading cause of death. In this study, we evaluated a gatekeeper training suicide prevention program that emphasizes emotional connectivity with students in crisis and incorporates the collaborative efforts between Housing/Residential Programs and the Counseling Center. Participants consisted of graduate…
Are Mothers Really "Gatekeepers" of Children?: Rural Mothers' Perceptions of Nonresident Fathers' Involvement in Low-Income Families

ERIC Educational Resources Information Center

Sano, Yoshie; Richards, Leslie N.; Zvonkovic, Anisa M.

2008-01-01

Guided by symbolic interactionism, this qualitative study based on interviews with 83 rural mothers investigated mothers' perceptions of nonresident fathers' involvement in low-income families. Contrary to some fathers' claims that mothers "gatekeep" their access to children, the majority of mothers in our study wanted increased father…
The Lucid Loneliness of the Gatekeeper: Exploring the Emotional Dimension in Principals' Work Lives

ERIC Educational Resources Information Center

Kelchtermans, Geert; Piot, Liesbeth; Ballet, Katrijn

2011-01-01

Based on a secondary analysis of studies on Flemish primary schools, the article argues that the metaphor of the gatekeeper, on the threshold between the outside-school and the inside-school world, is a powerful frame to capture some of the particular complexities of principals' emotional experience of themselves and their working conditions. More…
A Qualitative Study of the Experiences of Gatekeeping among PhD Counselor Educators

ERIC Educational Resources Information Center

Erbes, Carol A.

2013-01-01

The purpose of this study was to examine the gatekeeping experiences of a group of PhD counselor educators, by utilizing a phenomenological approach. This design was chosen as it could best examine the lived experiences of the participants. Nine PhD counselor educators participated in this study through a series of two interviews. All of the…
Pilot Study Evaluation of Suicide Prevention Gatekeeper Training Utilising STORM in a British University Setting

ERIC Educational Resources Information Center

Gask, Linda; Coupe, Nia; McElvenny, Damien; Green, Gill

2017-01-01

Recent years have seen increasing awareness of the wide range of mental health problems faced by students. Gatekeeper training has been shown to have a positive impact on knowledge and attitudes about suicide prevention, although the evidence for skills acquisition is limited. We utilised the STORM® training package in an exploratory study to…
The Short-Term Effectiveness of a Suicide Prevention Gatekeeper Training Program in a College Setting with Residence Life Advisers

ERIC Educational Resources Information Center

Tompkins, Tanya L.; Witt, Jody

2009-01-01

Although the college years prove to be a vulnerable time for students and a critical period for suicide prevention, few school-based prevention strategies have been empirically evaluated. The current study examined the short-term effects of Question, Persuade, and Refer (QPR), a gatekeeper training program that teaches how to recognize warning…
Exploring the Intersection of Beliefs toward Outdoor Play and Cold Weather among Northeast Minnesota's Formal Education and Non-Formal EE Communities

ERIC Educational Resources Information Center

Hughes, Amy Christine; Zak, Kevin; Ernst, Julie; Meyer, Rebecca

2017-01-01

In a notoriously cold-seasoned region, this paper explored how our formal education and non-formal environmental education (EE) gatekeepers of Northeastern Minnesota regard the importance of outdoor play and cold weather for young students. This research study explored the relationship between participant gatekeepers' beliefs of the benefits…

Coverage of Major Topics in Economics in the Undergraduate Curriculum: Economists as Gatekeepers.

ERIC Educational Resources Information Center

Prescott, Suzanne

Over the last 25 years, less attention has been devoted to the role of the economist as teacher or professor than to the role of economist as scholar or researcher. Teachers have been seen as passive recipients of advances in economics research that they simply hand on to their students. Yet teachers perform an important gatekeeping function when…
Meritocracy the Great American Myth? A Look at Gatekeeping in American Higher Education

ERIC Educational Resources Information Center

Pappas, Geri; Tremblay, Christopher W.

2010-01-01

Research on the concept of meritocracy and its role in college admissions is the major focus of this article. It explores the factors that contribute to the gatekeeping process and provides a historical context that led to the evolution of today's admission protocol. It focuses specifically on the strict meritocratic practices of many colleges as…
Acquiring Research Access: Perspectives from Gatekeepers and Parents of Children with Anorexia Nervosa

ERIC Educational Resources Information Center

Hunt, Tamara Jo-Lynne

2010-01-01

The purpose of this study was to understand the conditions necessary to gain research access to parents of children with anorexia. In this study, I also examined and explored avenues parents have for sharing their story and their experiences of parenting a child with anorexia as well as whether gatekeepers have a role in connecting parents and…
Social nature of eating could explain missing link between food insecurity and childhood obesity.

PubMed

Mata, Jutta; Dallacker, Mattea; Hertwig, Ralph

2017-01-01

We suggest that social factors are key to explain the missing link between food insecurity and obesity in children. Parents and public institutions are children's nutritional gatekeepers. They protect children from food insecurity by trimming down their consumption or by institutional support. To gauge children's food insecurity, evaluations across the different nutritional gatekeepers need to be integrated.
Bayer Facts of Science Education XV: A View from the Gatekeepers--STEM Department Chairs at America's Top 200 Research Universities on Female and Underrepresented Minority Undergraduate STEM Students

ERIC Educational Resources Information Center

Journal of Science Education and Technology, 2012

2012-01-01

Diversity and the underrepresentation of women, African-Americans, Hispanics and American Indians in the nation's science, technology, engineering and mathematics (STEM) fields are the subjects of the XV: A View from the Gatekeepers--STEM Department Chairs at America's Top 200 Research Universities on Female and Underrepresented Minority…
Don't Forget the Distributor! the Importance of Field Testing Draft Educational Materials with Key Gatekeepers before Production and Dissemination

ERIC Educational Resources Information Center

Flores, Alina L.; Prue, Christine E.; Panissidi, Paula

2010-01-01

Objective: This article presents the results of testing draft folic acid educational materials with key gatekeepers, leading to the development of a Spanish-language print advertisement, poster, and radio public service announcement (PSA) aimed at promoting folic acid consumption among 18- to 25-year-old young Latina adults, as well as a…
'We have the internet in our hands': Bangladeshi college students' use of ICTs for health information.

PubMed

Waldman, Linda; Ahmed, Tanvir; Scott, Nigel; Akter, Shahinoor; Standing, Hilary; Rasheed, Sabrina

2018-03-20

Information and Communications Technologies (ICTs) which enable people to access, use and promote health information through digital technology, promise important health systems innovations which can challenge gatekeepers' control of information, through processes of disintermediation. College students, in pursuit of sexual and reproductive health (SRH) information, are particularly affected by gatekeeping as strong social and cultural norms restrict their access to information and services. This paper examines mobile phone usage for obtaining health information in Mirzapur, Bangladesh. It contrasts college students' usage with that of the general population, asks whether students are using digital technologies for health information in innovative ways, and examines how gender affects this. This study relies on two surveys: a 2013-2014 General Survey that randomly sampled 854 households drawn from the general population and a 2015 Student Survey that randomly sampled 436 students from two Mirzapur colleges. Select focus group discussions and in-depth interviews were undertaken with students. Icddr,b's Ethical Review Board granted ethical clearance. The data show that Mirzapur's college students are economically relatively well positioned, more likely to own mobile and smart phones, and more aware of the internet than the general population. They are interested in health information and use phones and computers to access information. Moreover, they use digital technology to share previously-discreet information, adding value to that information and bypassing former gatekeepers. But access to health information is not entirely unfettered, affecting male and female students differently, and powerful gatekeepers, both old and new, can still control sources of information. Personal searches for SRH and the resultant online information shared through discrete, personal face-to-face discussions has some potential to challenge social norms. This is particularly so for women students, as sharing information may enable them to bypass gatekeepers and make decisions about reproduction. This suggests that digital health information seeking may be exercising a disruptive effect within the health sector. However, the extent of this disruption may depend, not on students' mobile phone usage, but on the degree to which powerful new gatekeepers are able to retain control over and market SRH information through students' peer-to-peer sharing.
Effect of Patient Experience on Bypassing a Primary Care Gatekeeper: a Multicenter Prospective Cohort Study in Japan.

PubMed

Aoki, Takuya; Yamamoto, Yosuke; Ikenoue, Tatsuyoshi; Kaneko, Makoto; Kise, Morito; Fujinuma, Yasuki; Fukuhara, Shunichi

2018-05-01

To discuss how best to implement the gatekeeping functionality of primary care; identifying the factors that cause patients to bypass their primary care gatekeepers when seeking care should be beneficial. To examine the association between patient experience with their primary care physicians and bypassing them to directly obtain care from higher-level healthcare facilities. This prospective cohort study was conducted in 13 primary care clinics in Japan. We assessed patient experience of primary care using the Japanese version of Primary Care Assessment Tool (JPCAT), which comprises six domains: first contact, longitudinality, coordination, comprehensiveness (services available), comprehensiveness (services provided), and community orientation. The primary outcome was the patient bypassing their usual primary care physician to seek care at a hospital, with this occurring at least once in a year. We used a Bayesian hierarchical model to adjust clustering within clinics and individual covariates. Data were analyzed from 205 patients for whom a physician at a clinic served as their usual primary care physician. The patient follow-up rate was 80.1%. After adjustment for patients' sociodemographic and health status characteristics, the JPCAT total score was found to be inversely associated with patient bypass behavior (odds ratio per 1 SD increase, 0.44; 95% credible interval, 0.21-0.88). The results of various sensitivity analyses were consistent with those of the primary analysis. We found that patient experience of primary care in Japan was inversely associated with bypassing a primary care gatekeeper to seek care at higher-level healthcare facilities, such as hospitals. Our findings suggest that primary care providers' efforts to improve patient experience should help to ensure appropriate use of healthcare services under loosely regulated gatekeeping systems; further studies are warranted.
Explaining the present GM business strategy on the EU food market: the gatekeepers' perspective.

PubMed

Inghelbrecht, Linde; Dessein, Joost; Van Huylenbroeck, Guido

2015-01-25

The use of genetically modified (GM) crops and their applications is partially suppressed in European Union (EU) agriculture, even if one would expect otherwise given their complementarity with the neoliberal and industrialised EU agricultural regime in place. By applying a qualitative content analysis, this paper analyses how food manufacturers and retailers (referred to as gatekeepers in the food industry) explain and defend the exclusion of GM-labelled food products on the EU market. The study design places emphasis on the role of perceptions in the strategic behaviour of gatekeepers and on the role of interaction in this regard, as we assume that the way in which gatekeepers perceive the 'rules of the game' for commercialising GM crop applications on the EU food market will be influenced by their interaction with other agribusiness actors. In a first stage, the analysis determines thematic congruence in the (types of) perceptions that explain an agribusiness actor's overall interpretation of the EU business environment for GM crop applications. This perceived 'structuring arena' (SA) for GM crop applications - as conceptualised within our framework - contains areas of either internal and external tensions, that have a compelling or non-committal influence on the agribusiness actor's interpretation. In a second stage, the analysis particularly defines how gatekeepers in the food industry perceive and experience the SA for GM crop applications on the EU market, and how these perceptual tensions subsequently influence their strategic behaviour for GM-labelled products on the EU market. Finally, we highlight how these perceptions and actions (or inaction) suppress the main changes in practice that are necessary to manage this wicked problem. Copyright © 2014 Elsevier B.V. All rights reserved.
CRISPR-Cas Gatekeeper: Slow on the Uptake but Gets the Job Done.

PubMed

Whitaker, Rachel J; Vanderpool, Carin K

2016-02-10

Microbial CRISPR-Cas acts as a defense, but also as a gatekeeper controlling the flow of new genes into microbial genomes. In a recent Cell paper, Jiang et al. (2016) uncover the functional importance of transcription-dependent RNA targeting in type III-A CRISPR-Cas antiviral defense and provide insight into the co-evolution of virus-host symbioses. Copyright © 2016 Elsevier Inc. All rights reserved.
Defenders against Threats or Enablers of Opportunities: The Screening Role Played by Gatekeepers in Researching Older People in Care Homes

ERIC Educational Resources Information Center

Scourfield, Peter

2012-01-01

This paper emerges from a case study of the system of statutory reviews in older people's care homes in the UK. Informed by a review of selected literature on gaining access, this paper provides a critical account of the process of negotiating access with gatekeepers (chiefly, care home managers). The negotiations were time-consuming and largely…
Narratives and gatekeeping: making sense of triage nurses' practice.

PubMed

Johannessen, Lars E F

2018-04-17

It is well documented that emergency service staff consider some patients to be 'inappropriate attenders'. A central example is 'trivia', denoting patients with medical problems considered too 'trivial' to warrant attention. Although research has repeatedly shown that frontline staff violate guidelines in turning away 'trivial' patients, existing research has paid insufficient attention to why staff are willing to engage in guideline-violating gatekeeping, which may put both themselves and 'trivial' patients at risk. To address this issue, the present article explores nurses' narratives about 'trivial' patients - referred to in this context as 'GP patients' - drawing on fieldwork data from a Norwegian emergency service. The article reconstructs three narrative clusters, showing that nurses' gatekeeping is motivated by concerns for the patient being turned away, for nurses and more critically ill patients, and for the service they work for. Some of the issues embedded in these narratives have been under-analysed in previous research - most importantly, the role of identity and emotion in nurses' gatekeeping, and how patient narratives can function as 'social prognoses' in nurses' assessments. Analysis of these narratives also reveals an antagonistic relationship between nurses and 'trivial' patients that contradicts nurses' ethical guidelines and indicates a need for healthcare reform. © 2018 Foundation for the Sociology of Health & Illness.
Gatekeeping and its impact on father involvement among Black South Africans in rural KwaZulu-Natal.

PubMed

Makusha, Tawanda; Richter, Linda

2016-01-01

Involved and caring fatherhood contributes to the health and wellbeing of children, women and men. The corollary is also true - men, women and children are affected when fathers are not involved or supportive of their children. Many factors affect fathers' involvement, including women's attitudes, the history and nature of the relationship between mother and father, and the cultural context. This study explores gatekeeping and its impact on father involvement among Black South Africans in rural KwaZulu-Natal. Among married couples, gatekeeping occurs with respect to childcare and housework through women's attempts to validate their maternal identity according to socially and culturally constructed gender roles. Among unmarried, non-resident parents, women control father-child contact and involvement, with mothers and/or their families either facilitating or inhibiting father involvement. In this context, we found that cultural gatekeeping had a huge impact on father involvement, with the non-payment of inhlawulo or lobola regulating father-child involvement. In a country like South Africa, where there is high non-marital fertility and father-child non-residence, future research, parenting and family programmes should focus on strategies that encourage positive paternal involvement as well as maternal and cultural support for father involvement, regardless of parental relationship and residence status.
External validity and anchoring heuristics: application of DUNDRUM-1 to secure service gatekeeping in South Wales.

PubMed

Lawrence, Daniel; Davies, Tracey-Lee; Bagshaw, Ruth; Hewlett, Paul; Taylor, Pamela; Watt, Andrew

2018-02-01

Aims and method Structured clinical judgement tools provide scope for the standardisation of forensic service gatekeeping and also allow identification of heuristics in this decision process. The DUNDRUM-1 triage tool was completed retrospectively for 121 first-time referrals to forensic services in South Wales. Fifty were admitted to medium security, 49 to low security and 22 remained in open conditions. DUNDRUM-1 total scores differed appropriately between different levels of security. However, regression revealed heuristic anchoring on the 'legal process' and 'immediacy of risk due to mental disorder' items. Clinical implications Patient placement was broadly aligned with DUNDRUM-1 recommendations. However, not all triage items informed gatekeeping decisions. It remains to be seen whether decisions anchored in this way are effective. Declaration of interest Dr Mark Freestone gave permission for AUC values from Freestone et al. (2015) to be presented here for comparison.
Addiction Treatment Professionals Are Not the Gatekeepers of Recovery.

PubMed

Humphreys, Keith

2015-01-01

Addiction treatment is beneficial to many individuals who have substance use disorders. However, only a minority of individuals who recover from addiction receive it. Despite this, addiction treatment is sometimes granted the status of the "gatekeeper of recovery." The myth that treatment is necessary for recovery has no empirical support. It also undermines the confidence of individuals in their ability to change on their own and is unduly dismissive of the efforts of nonprofessional helpers.
A Smart pH-responsive Nano-Carrier as a Drug Delivery System: A hybrid system comprised of mesoporous nanosilica MCM-41 (as a nano-container) & a pH-sensitive polymer (as smart reversible gatekeepers): Preparation, characterization and in vitro release studies of an anti-cancer drug.

PubMed

Abbaszad Rafi, Abdolrahim; Mahkam, Mehrdad; Davaran, Soodabeh; Hamishehkar, Hamed

2016-10-10

A smart pH-responsive drug nano-carrier for controlled release of anti-cancer therapeutics was developed through a facile route. The nano-carrier consisted of two main parts: first, the nano-container part (that mesoporous silica nanoparticles (MCM-41) were selected for this aim); and second, pH-sensitive gatekeepers (that a pH-sensitive polymer, Poly4-vinylpyridine, played this role). In the first step, MCM-41 was synthesized via template assisted sol-gel process. In the second step, polymerizable functional groups were attached onto pore entrances rather than inside walls. In the third step, polymeric gatekeepers were introduced onto pore entrances via precipitation polymerization of functionalized MCM-41 with monomers. Different methods and analysis, such as Fourier Transform Infrared Spectroscopy (FT-IR), X-ray Powder Diffraction (XRD), Thermo-Gravimetric Analysis (TGA), Energy-Dispersive X-ray Spectroscopy (EDX), Zeta Potentials, Dynamic Light Scattering (DLS), Field Emission Scanning Electron Microscope (FE-SEM) and Transmission Electron Microscopy (TEM) were employed to approve the successful attachment of gatekeepers. Furthermore, the release studies of methotroxate (MTX), an anti-cancer drug, were performed in different media (pH4, 5.8 and 7.4) at 37±1°C. The release profiles and curves show that the release rates are completely pH-dependent and it proceeds with a decrease in pH. It is concluded that in the higher pH the gatekeepers are in their close state, but they switch to the open state as a consequence of repulsive forces between positively charged polymer chains appear in acidic media. The results suggest that this smart nano-carrier can be considered as an appropriate candidate to deliver therapeutics to cancerous tissues. Copyright © 2016 Elsevier B.V. All rights reserved.
Fathers’ Involvement in Child Health Care: Associations with Prenatal Involvement, Parents’ Beliefs, and Maternal Gatekeeping

PubMed Central

Zvara, B.J.; Schoppe-Sullivan, Sarah J.; Dush, Claire M. Kamp

2015-01-01

Using data from 182 dual-earner couples experiencing the transition to parenthood, this study examined associations between prenatal involvement, gender role beliefs, and maternal gatekeeping and new fathers’ involvement in child health care. Results indicated that prenatal father involvement was associated with both fathers’ direct engagement in child health care and fathers’ perceived influence in child health-related decision-making. Fathers also demonstrated greater direct engagement in child health care when mothers held more nontraditional beliefs about gender roles. Moreover, when mothers were more encouraging of fathers’ involvement in childrearing, fathers felt more influential in child health-related decision-making, whereas when mothers engaged in greater gate closing behavior, fathers with more traditional gender role beliefs felt less influential in child health-related decision-making. This study suggests that fathers’ prenatal involvement, mothers’ beliefs, and maternal gatekeeping may play a role in the development of new fathers’ involvement in child health care at the transition to parenthood. PMID:26405366
From Regional to National Clouds: TV Coverage in the Czech Republic

PubMed Central

Sucháček, Jan; Sed’a, Petr; Friedrich, Václav; Wachowiak-Smolíková, Renata; Wachowiak, Mark P.

2016-01-01

Media, and particularly TV media, have a great impact on the general public. In recent years, spatial patterns of information and the relevance of intangible geographies have become increasingly important. Gatekeeping plays a critical role in the selection of information that is transformed into media. Therefore, gatekeeping, through national media, also co-forms the generation of mental maps. In this paper, correspondence analysis (a statistical method) combined with cloud lines (a new visual analytics technique) is used to analyze how individual major regional events in one of the post-communist countries, the Czech Republic, penetrate into the media on a national scale. Although national news should minimize distortions about regions, this assumption has not been verified by our research. Impressions presented by the media of selected regions that were markedly influenced by one or several events in those regions demonstrate that gatekeepers, especially news reporters, functioned as a filter by selecting only a few specific, and in many cases, unusual events for dissemination. PMID:27824947
Structural Mechanism of the Pan-BCR-ABL Inhibitor Ponatinib (AP24534): Lessons for Overcoming Kinase Inhibitor Resistance

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

Zhou, Tianjun; Commodore, Lois; Huang, Wei-Sheng

2012-01-20

The BCR-ABL inhibitor imatinib has revolutionized the treatment of chronic myeloid leukemia. However, drug resistance caused by kinase domain mutations has necessitated the development of new mutation-resistant inhibitors, most recently against the T315I gatekeeper residue mutation. Ponatinib (AP24534) inhibits both native and mutant BCR-ABL, including T315I, acting as a pan-BCR-ABL inhibitor. Here, we undertook a combined crystallographic and structure-activity relationship analysis on ponatinib to understand this unique profile. While the ethynyl linker is a key inhibitor functionality that interacts with the gatekeeper, virtually all other components of ponatinib play an essential role in its T315I inhibitory activity. The extensive networkmore » of optimized molecular contacts found in the DFG-out binding mode leads to high potency and renders binding less susceptible to disruption by single point mutations. The inhibitory mechanism exemplified by ponatinib may have broad relevance to designing inhibitors against other kinases with mutated gatekeeper residues.« less
Measuring the effectiveness of scientific gatekeeping.

PubMed

Siler, Kyle; Lee, Kirby; Bero, Lisa

2015-01-13

Peer review is the main institution responsible for the evaluation and gestation of scientific research. Although peer review is widely seen as vital to scientific evaluation, anecdotal evidence abounds of gatekeeping mistakes in leading journals, such as rejecting seminal contributions or accepting mediocre submissions. Systematic evidence regarding the effectiveness--or lack thereof--of scientific gatekeeping is scant, largely because access to rejected manuscripts from journals is rarely available. Using a dataset of 1,008 manuscripts submitted to three elite medical journals, we show differences in citation outcomes for articles that received different appraisals from editors and peer reviewers. Among rejected articles, desk-rejected manuscripts, deemed as unworthy of peer review by editors, received fewer citations than those sent for peer review. Among both rejected and accepted articles, manuscripts with lower scores from peer reviewers received relatively fewer citations when they were eventually published. However, hindsight reveals numerous questionable gatekeeping decisions. Of the 808 eventually published articles in our dataset, our three focal journals rejected many highly cited manuscripts, including the 14 most popular; roughly the top 2 percent. Of those 14 articles, 12 were desk-rejected. This finding raises concerns regarding whether peer review is ill--suited to recognize and gestate the most impactful ideas and research. Despite this finding, results show that in our case studies, on the whole, there was value added in peer review. Editors and peer reviewers generally--but not always-made good decisions regarding the identification and promotion of quality in scientific manuscripts.

Single-step electrochemical functionalization of double-walled carbon nanotube (DWCNT) membranes and the demonstration of ionic rectification

PubMed Central

2013-01-01

Carbon nanotube (CNT) membranes allow the mimicking of natural ion channels for applications in drug delivery and chemical separation. Double-walled carbon nanotube membranes were simply functionalized with dye in a single step instead of the previous two-step functionalization. Non-faradic electrochemical impedance spectra indicated that the functionalized gatekeeper by single-step modification can be actuated to mimic the protein channel under bias. This functional chemistry was proven by a highly efficient ion rectification, wherein the highest experimental rectification factor of ferricyanide was up to 14.4. One-step functionalization by electrooxidation of amine provides a simple and promising functionalization chemistry for the application of CNT membranes. PMID:23758999
Gatekeeping practices of music therapy academic programs and internships: a national survey.

PubMed

Hsiao, Feilin

2014-01-01

Gatekeeping safeguards access to the practice of a profession to ensure the quality of clinical services. It involves selective admission, continuous evaluation, and timely and ethical decisions in response to trainees with severe professional competency problems (SPCP). To date, little information is available concerning gatekeeping practices in the field of music therapy. This study investigated the extent and outcomes of gatekeeping practices across academic programs and National Roster internship sites approved by the American Music Therapy Association. Specifically, it examined the prevalence of trainees with SPCP, program-wide precautionary measures, common indicators of trainees with SPCP, remedial strategies, and supports and barriers to effective management. Thirty-two academic program directors and 77 internship directors completed an online survey. Responses were compiled into aggregate form (frequencies & percentages) for analysis. Chi-square tests with Yates' correction were applied to compare the differences between academic programs and internships. A significantly higher percentage of academic programs (93.8%) reported having at least one trainee with SPCP over the past 5 years than did internships (66.2%). The most common indicators of competency problems included inadequate music skill development, emotional instability, limited communication skills, deficient interpersonal skills, defensiveness in supervision, and lack of insight. Typical remedial methods included referral to personal therapy, increased supervision, and repetition of practicum or extension of internship. Issues regarding trainees with SPCP are frequently addressed by academic and internship program directors. Improving clarity within professional guidelines and establishing more rigorous and consistent standards across training programs are recommended. © the American Music Therapy Association 2014. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.
Marital Problems, Maternal Gatekeeping Attitudes, and Father-Child Relationships in Adolescence

PubMed Central

Stevenson, Matthew M.; Fabricius, William V.; Cookston, Jeffrey T.; Parke, Ross D.; Coltrane, Scott; Braver, Sanford L.; Saenz, Delia S.

2013-01-01

We evaluated maternal gatekeeping attitudes as a mediator of the relation between marital problems and father-child relationships in three waves when children were in 7th through 10th grade. We assessed each parent’s contribution to the marital problems experienced by the couple. Findings from mediational and cross-lagged structural equation models revealed that increased marital problem behaviors on the part of mothers at wave 1 predicted increased maternal gatekeeping attitudes at wave 2 which in turn predicted decreased amounts of father-adolescent interaction at wave 3. Decreased amounts of interaction with either parent were associated within each wave with adolescents’ perceptions that they mattered less to that parent. Amount of interaction with fathers at wave 2 positively predicted changes in boys’ perceptions of how much they mattered to their fathers at wave 3, and amount of interaction with mothers at wave 2 positively predicted changes in girls’ perceptions of how much they mattered to their mothers at wave 3. The findings did not differ for European-American versus Mexican-American families, or for biological fathers versus step-fathers. PMID:24364832
Reconsidering the Gatekeeper Paradigm for Percutaneous Coronary Intervention in Stable Coronary Disease Management.

PubMed

Schulman-Marcus, Joshua; Weintraub, William S; Boden, William E

2017-10-15

Major randomized clinical trials over the last decade support the role of optimal medical therapy for the initial management approach for patients with stable coronary artery disease (CAD), whereas percutaneous coronary intervention (PCI) ought to be reserved for patients with persistent symptoms despite optimal medical therapy. Likewise, several studies have continued to demonstrate the superiority of coronary artery bypass grafting surgery over PCI in many patients with extensive multivessel CAD, especially those with diabetes. Nevertheless, the decision-making paradigm for patients with stable CAD often continues to propagate the upfront use of "ad hoc PCI" and disadvantages alternative therapeutic approaches. In our editorial, we discuss how multiple systemic and interpersonal factors continue to favor early revascularization with PCI in stable patients. We discuss whether the interventional cardiologist can be an unbiased "gatekeeper" for the use of PCI or whether other physicians should also be involved with the patient in decision-making. Finally, we offer suggestions that can redefine the gatekeeper role to facilitate an evidence-based approach that embraces shared decision-making. Copyright © 2017 Elsevier Inc. All rights reserved.
Gatekeepers in the healthcare sector: Knowledge and Bourdieu's concept of field.

PubMed

Collyer, Fran M; Willis, Karen F; Lewis, Sophie

2017-08-01

Choice is an imperative for patients in the Australian healthcare system. The complexity of this healthcare 'maze', however, means that successfully navigating and making choices depends not only on the decisions of patients, but also other key players in the healthcare sector. Utilising Bourdieu's concepts of capital, habitus and field, we analyse the role of gatekeepers (i.e., those who control access to resources, services and knowledge) in shaping patients' experiences of healthcare, and producing opportunities to enable or constrain their choices. Indepth interviews were conducted with 41 gatekeepers (GPs, specialists, nurses, hospital administrators and policymakers), exploring how they acquire and use knowledge within the healthcare system. Our findings reveal a hierarchy of knowledges and power within the healthcare field which determines the forms of knowledge that are legitimate and can operate as capital within this complex and dynamic arena. As a consequence, forms of knowledge which can operate as capital, are unequally distributed and strategically controlled, ensuring democratic 'reform' remains difficult and 'choices' limited to those beneficial to private medicine. Copyright © 2017 Elsevier Ltd. All rights reserved.
[Hospital clinical engineer orientation and function in the maintenance system of hospital medical equipment].

PubMed

Li, Bin; Zheng, Yunxin; He, Dehua; Jiang, Ruiyao; Chen, Ying; Jing, Wei

2012-03-01

The quantity of medical equipment in hospital rise quickly recent year. It provides the comprehensive support to the clinical service. The maintenance of medical equipment becomes more important than before. It is necessary to study on the orientation and function of clinical engineer in medical equipment maintenance system. Refer to three grade health care system, the community doctors which is called General practitioner, play an important role as the gatekeeper of health care system to triage and cost control. The paper suggests that hospital clinical engineer should play similar role as the gatekeeper of medical equipment maintenance system which composed by hospital clinical engineer, manufacture engineer and third party engineer. The hospital clinical engineer should be responsible of guard a pass of medical equipment maintenance quality and cost control. As the gatekeeper, hospital clinical engineer should take the responsibility of "General engineer" and pay more attention to safety and health of medical equipment. The responsibility description and future transition? development of clinical engineer as "General Engineer" is discussed. More attention should be recommended to the team building of hospital clinical engineer as "General Engineer".
Identification of a Non-Gatekeeper Hot Spot for Drug-Resistant Mutations in mTOR Kinase.

PubMed

Wu, Tzung-Ju; Wang, Xiaowen; Zhang, Yanjie; Meng, Linghua; Kerrigan, John E; Burley, Stephen K; Zheng, X F Steven

2015-04-21

Protein kinases are therapeutic targets for human cancer. However, "gatekeeper" mutations in tyrosine kinases cause acquired clinical resistance, limiting long-term treatment benefits. mTOR is a key cancer driver and drug target. Numerous small-molecule mTOR kinase inhibitors have been developed, with some already in human clinical trials. Given our clinical experience with targeted therapeutics, acquired drug resistance in mTOR is thought likely, but not yet documented. Herein, we describe identification of a hot spot (L2185) for drug-resistant mutations, which is distinct from the gatekeeper site, and a chemical scaffold refractory to drug-resistant mutations. We also provide new insights into mTOR kinase structure and function. The hot spot mutations are potentially useful as surrogate biomarkers for acquired drug resistance in ongoing clinical trials and future treatments and for the design of the next generation of mTOR-targeted drugs. Our study provides a foundation for further research into mTOR kinase function and targeting. Copyright © 2015 The Authors. Published by Elsevier Inc. All rights reserved.
GABAB receptor cell surface export is controlled by an endoplasmic reticulum gatekeeper

PubMed Central

Doly, Stéphane; Shirvani, Hamasseh; Gäta, Gabriel; Meye, Frank; Emerit, Michel-Boris; Enslen, Hervé; Achour, Lamia; Pardo-Lopez, Liliana; Kwon, Yang Seung; Armand, Vincent; Gardette, Robert; Giros, Bruno; Gassmann, Martin; Bettler, Bernhard; Mameli, Manuel; Darmon, Michèle; Marullo, Stefano

2016-01-01

Summary Endoplasmic reticulum (ER) release and cell surface export of many G protein-coupled receptors (GPCRs), are tightly regulated. For GABAB receptors of GABA, the major mammalian inhibitory neurotransmitter, the ligand-binding GB1 subunit is maintained in the ER by unknown mechanisms in the absence of hetero-dimerization with the GB2 subunit. We report that GB1 retention is regulated by a specific gatekeeper, PRAF2. This ER resident transmembrane protein binds to GB1, preventing its progression in the biosynthetic pathway. GB1 release occurs upon competitive displacement from PRAF2 by GB2. PRAF2 concentration, relative to that of GB1 and GB2, tightly controls cell surface receptor density and controls GABAB function in neurons. Experimental perturbation of PRAF2 levels in vivo caused marked hyperactivity disorders in mice. These data reveal an unanticipated major impact of specific ER gate-keepers on GPCR function and identify PRAF2 as a new molecular target with therapeutic potential for psychiatric and neurological diseases involving GABAB function. PMID:26033241
Designing dual inhibitors of Mdm2/MdmX: Unexpected coupling of water with gatekeeper Y100/99.

PubMed

Lee, Xiong An; Verma, Chandra; Sim, Adelene Y L

2017-08-01

Mdm2 and MdmX share high structural similarity in their N-terminal domains, yet dual inhibitors are challenging to design due to differences in the conformations of the binding pockets, and notably of the proposed gatekeeper residue, Y100/99. Analysis of crystal structures and molecular dynamics (MD) simulations of complexes of Mdm2 and MdmX resulted in the identification of a water molecule with a long residence time that appears to be modulated by the conformation of Y100/99. These observations lead us to speculate that dual inhibitors either (i) stabilize both Mdm2 and MdmX with Y100/99 in the open conformation typically seen in complexes of Mdm2 with p53, or (ii) the dual inhibitors are agnostic to the conformation of Y100/99. The recently developed potent dual inhibitory stapled peptide Atsp7041 appears to be agnostic to the conformation of the gatekeeper residue. Proteins 2017; 85:1493-1506. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.
A state's approach to suicide prevention awareness: gatekeeper training in Kentucky.

PubMed

Cerel, Julie; Padgett, Jason H; Robbins, Vestena; Kaminer, Barbara

2012-01-01

As part of Preventing Suicide: Kentucky's Plan, a gatekeeper training was implemented. The implementation of this brief educational intervention and changes in participants' suicide prevention attitudes were examined. Data were collected from 3,958 people in 213 sessions from May 2004 to August 2006. Participants reported high levels of satisfaction with the trainings. Immediately following the training, participants showed substantial increases in their perception of their suicide knowledge and their perceived efficacy to help someone who displays signs of suicide. QPR was widely disseminated across the state and shows promise to change immediate beliefs and feelings of efficacy.
Exploring opportunities to project a "responsible man" image: gatekeepers views of young men's sexual and reproductive health needs in Uttaranchal, India.

PubMed

Khan, M E; Mishra, Anurag; Morankar, Sudhakar

Increase in extramarital sex among youths, gender-based violence, lack of contraceptive knowledge among newly married couples and lack of knowledge of protection against diseases like STIs/HIV are the information and service needs of young people that need to be addressed urgently in order to make them future knowledgeable, responsible, and non-violent partners. In addressing these needs the gatekeepers, including parents, formal and informal community leaders and teachers, play a critical role, by facilitating/hindering access to appropriate and correct information about sexual and reproductive health to young people. The study was conducted in a district of Uttaranchal, India. The specific objective was to understand the social context and gatekeepers' views on family planning and sexual and reproductive health needs of young men. Thirty-two in-depth interviews and four focus group discussions were conducted with parents, formal and informal community leaders, teachers, and selected development officials. The findings indicate that gatekeepers are worried about rapid changes in the aspiration, expectation, and behavior of young men. Most of them were seriously concerned about the increasing drinking habit, use of drugs, and changing values of sexuality leading to various risk behaviors among young men. They felt that many of these changes are consequences of wider societal changes, rising aspirations, explosion of electronic media, and globalization of a new youth culture where extramarital sex, alcohol consumption, and violence are expressions of different facets of masculinity and symbols of the affluent class. Overall, there was a feeling that TV/films and their peers now influence more the socialization of young people and parents are losing control in guidance and mentoring of their children.
Gatekeepers or intermediaries? The role of clinicians in commercial genomic testing.

PubMed

McGowan, Michelle L; Fishman, Jennifer R; Settersten, Richard A; Lambrix, Marcie A; Juengst, Eric T

2014-01-01

Many commentators on "direct-to-consumer" genetic risk information have raised concerns that giving results to individuals with insufficient knowledge and training in genomics may harm consumers, the health care system, and society. In response, several commercial laboratories offering genomic risk profiling have shifted to more traditional "direct-to-provider" (DTP) marketing strategies, repositioning clinicians as the intended recipients of advertising of laboratory services and as gatekeepers to personal genomic information. Increasing popularity of next generation sequencing puts a premium on ensuring that those who are charged with interpreting, translating, communicating and managing commercial genomic risk information are appropriately equipped for the job. To shed light on their gatekeeping role, we conducted a study to assess how and why early clinical users of genomic risk assessment incorporate these tools in their clinical practices and how they interpret genomic information for their patients. We conducted qualitative in-depth interviews with 18 clinicians providing genomic risk assessment services to their patients in partnership with DNA Direct and Navigenics. Our findings suggest that clinicians learned most of what they knew about genomics directly from the commercial laboratories. Clinicians rely on the expertise of the commercial laboratories without the ability to critically evaluate the knowledge or assess risks. DTP service delivery model cannot guarantee that providers will have adequate expertise or sound clinical judgment. Even if clinicians want greater genomic knowledge, the current market structure is unlikely to build the independent substantive expertise of clinicians, but rather promote its continued outsourcing. Because commercial laboratories have the most "skin in the game" financially, genetics professionals and policymakers should scrutinize the scientific validity and clinical soundness of the process by which these laboratories interpret their findings to assess whether self-interested commercial sources are the most appropriate entities for gate-keeping genomic interpretation.
Therapeutic strategies to overcome crizotinib resistance in non-small cell lung cancers harboring the fusion oncogene EML4-ALK

PubMed Central

Katayama, Ryohei; Khan, Tahsin M.; Benes, Cyril; Lifshits, Eugene; Ebi, Hiromichi; Rivera, Victor M.; Shakespeare, William C.; Iafrate, A. John; Engelman, Jeffrey A.; Shaw, Alice T.

2011-01-01

The echinoderm microtubule-associated protein-like 4 (EML4)-anaplastic lymphoma kinase (ALK) fusion oncogene represents a molecular target in a small subset of non-small cell lung cancers (NSCLCs). This fusion leads to constitutive ALK activation with potent transforming activity. In a pivotal phase 1 clinical trial, the ALK tyrosine kinase inhibitor (TKI) crizotinib (PF-02341066) demonstrated impressive antitumor activity in the majority of patients with NSCLC harboring ALK fusions. However, despite these remarkable initial responses, cancers eventually develop resistance to crizotinib, usually within 1 y, thereby limiting the potential clinical benefit. To determine how cancers acquire resistance to ALK inhibitors, we established a model of acquired resistance to crizotinib by exposing a highly sensitive EML4-ALK–positive NSCLC cell line to increasing doses of crizotinib until resistance emerged. We found that cells resistant to intermediate doses of crizotinib developed amplification of the EML4-ALK gene. Cells resistant to higher doses (1 μM) also developed a gatekeeper mutation, L1196M, within the kinase domain, rendering EML4-ALK insensitive to crizotinib. This gatekeeper mutation was readily detected using a unique and highly sensitive allele-specific PCR assay. Although crizotinib was ineffectual against EML4-ALK harboring the gatekeeper mutation, we observed that two structurally different ALK inhibitors, NVP-TAE684 and AP26113, were highly active against the resistant cancer cells in vitro and in vivo. Furthermore, these resistant cells remained highly sensitive to the Hsp90 inhibitor 17-AAG. Thus, we have developed a model of acquired resistance to ALK inhibitors and have shown that second-generation ALK TKIs or Hsp90 inhibitors are effective in treating crizotinib-resistant tumors harboring secondary gatekeeper mutations. PMID:21502504
Demand management: an audit of chemical pathology test rejections by an electronic gate-keeping system at an academic hospital in Cape Town.

PubMed

Smit, Ida; Zemlin, Annalise E; Erasmus, Rajiv T

2015-07-01

Demand management is an area of laboratory activity, which is becoming increasingly important. Within the health-care system, demand management can be defined as the use of health resources to maximise its utility. Tygerberg Hospital has introduced an electronic gate-keeping system. Chemistry tests which generate the highest cost are subjected to this system and may be automatically rejected according to a set of rules. This study aimed: (1) to identify the number of chemistry tests rejected by the eGK; (2) to identify which of these rejected tests were subsequently restored and (3) to assess the impact of rejections on clinical outcome and cost-saving. A retrospective audit was conducted to determine the number of chemistry tests rejected and subsequently restored over a 6-month period. The case-notes of patients for whom requested tests previously rejected had been restored were randomly selected and investigated to assess clinical impact. Any cost-saving was calculated. A total of 68,480 tests were subjected to gate-keeping, and 4605 tests (6.7%) were rejected while 679 (14.7%) of these were restored by the requestor phoning the laboratory after obtaining authorisation. After examining a subset of clinical notes it was found that in most cases (80%), patient care was unaffected. The total cost saved was £ 25,387. The majority of the rejected tests were unnecessary and following rejection, real savings were made. Electronic gate-keeping is a simple, effective and sustainable method of demand management. © The Author(s) 2015 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav.
A mixture gatekeeping procedure based on the Hommel test for clinical trial applications.

PubMed

Brechenmacher, Thomas; Xu, Jane; Dmitrienko, Alex; Tamhane, Ajit C

2011-07-01

When conducting clinical trials with hierarchically ordered objectives, it is essential to use multiplicity adjustment methods that control the familywise error rate in the strong sense while taking into account the logical relations among the null hypotheses. This paper proposes a gatekeeping procedure based on the Hommel (1988) test, which offers power advantages compared to other p value-based tests proposed in the literature. A general description of the procedure is given and details are presented on how it can be applied to complex clinical trial designs. Two clinical trial examples are given to illustrate the methodology developed in the paper.
Disrupting gatekeeping practices: Journalists’ source selection in times of crisis

PubMed Central

van der Meer, Toni G.L.A.; Verhoeven, Piet; Beentjes, Johannes W.J.; Vliegenthart, Rens

2016-01-01

As gatekeepers, journalists have the power to select the sources that get a voice in crisis coverage. The aim of this study is to find out how journalists select sources during a crisis. In a survey, journalists were asked how they assess the following sources during an organizational crisis: news agencies, an organization undergoing a crisis, and the general public. The sample consisted of 214 Dutch experienced journalists who at least once covered a crisis. Using structural equation modeling, sources’ likelihood of being included in the news was predicted using five source characteristics: credibility, knowledge, willingness, timeliness, and the relationship with the journalist. Findings indicated that during a crisis, news agencies are most likely to be included in the news, followed by the public, and finally the organization. The significance of the five source characteristics is dependent on source type. For example, to be used in the news, news agencies and organizations should be mainly evaluated as knowledgeable, whereas information from the public should be both credible and timely. In addition, organizations should not be seen as too willing or too eager to communicate. The findings imply that, during a crisis, journalists remain critical gatekeepers; however, they rely mainly on familiar sources. PMID:29278263
Disrupting gatekeeping practices: Journalists' source selection in times of crisis.

PubMed

van der Meer, Toni G L A; Verhoeven, Piet; Beentjes, Johannes W J; Vliegenthart, Rens

2017-10-01

As gatekeepers, journalists have the power to select the sources that get a voice in crisis coverage. The aim of this study is to find out how journalists select sources during a crisis. In a survey, journalists were asked how they assess the following sources during an organizational crisis: news agencies, an organization undergoing a crisis, and the general public. The sample consisted of 214 Dutch experienced journalists who at least once covered a crisis. Using structural equation modeling, sources' likelihood of being included in the news was predicted using five source characteristics: credibility, knowledge, willingness, timeliness, and the relationship with the journalist. Findings indicated that during a crisis, news agencies are most likely to be included in the news, followed by the public, and finally the organization. The significance of the five source characteristics is dependent on source type. For example, to be used in the news, news agencies and organizations should be mainly evaluated as knowledgeable, whereas information from the public should be both credible and timely. In addition, organizations should not be seen as too willing or too eager to communicate. The findings imply that, during a crisis, journalists remain critical gatekeepers; however, they rely mainly on familiar sources.
Effects of a Program to Improve Mental Health Literacy for Married Immigrant Women in Korea.

PubMed

Choi, Yun-Jung

2017-08-01

This study aimed to develop and evaluate a mental health improvement program for the acculturative stress and mental health literacy of married immigrant women using bilingual gatekeepers. Bilingual gatekeepers were recruited from multicultural centers and trained to provide 8-week structured mental health improvement services to the women in the experimental group using a mental health improvement guidebook developed by the authors in 8 different languages. The program was effective in improving mental health and mental health literacy scores as well as reducing the degree of acculturative stress. This study offers a model of effective mental healthcare for multicultural communities. Copyright © 2017 Elsevier Inc. All rights reserved.
Does a gatekeeper suicide prevention program work in a school setting? Evaluating training outcome and moderators of effectiveness.

PubMed

Tompkins, Tanya L; Witt, Jody; Abraibesh, Nadia

2009-12-01

The current study sought to evaluate the suicide prevention gatekeeper training program QPR (Question, Persuade, and Refer) among school personnel using a non-equivalent control group design. Substantial gains were demonstrated from pre- to post-test for attitudes, knowledge, and beliefs regarding suicide and suicide prevention. Exploratory analyses revealed the possible moderating effects of age, professional role, prior training, and recent contact with suicidal youth on QPR participants' general knowledge, questioning, attitudes toward suicide and suicide prevention, QPR quiz scores, and self-efficacy. The need for replication using a more rigorous experimental design in the context of strong community collaboration is discussed.
Intimate Partner Violence, Maternal Gatekeeping, and Child Conduct Problems

PubMed Central

Zvara, Bharathi J.; Mills-Koonce, W. Roger; Cox, Martha

2017-01-01

We examined the mediating role of parenting behavior on the relationship between intimate partner violence and child conduct problems, as well as the moderating role of maternal gatekeeping to these associations. The sample (N = 395) is from a longitudinal study of rural poverty in the eastern United States, exploring the ways in which child, family, and contextual factors shape child development over time. Study findings indicate that a father’s harsh–intrusive parenting behavior may be a key mediating pathway linking intimate partner violence and child conduct problems. Study findings further provide evidence for problematic outcomes for children when mothers encourage fathers with high levels of harsh–intrusive parenting to interact with their children. PMID:28943690

Tactical Synthesis Of Efficient Global Search Algorithms

NASA Technical Reports Server (NTRS)

Nedunuri, Srinivas; Smith, Douglas R.; Cook, William R.

2009-01-01

Algorithm synthesis transforms a formal specification into an efficient algorithm to solve a problem. Algorithm synthesis in Specware combines the formal specification of a problem with a high-level algorithm strategy. To derive an efficient algorithm, a developer must define operators that refine the algorithm by combining the generic operators in the algorithm with the details of the problem specification. This derivation requires skill and a deep understanding of the problem and the algorithmic strategy. In this paper we introduce two tactics to ease this process. The tactics serve a similar purpose to tactics used for determining indefinite integrals in calculus, that is suggesting possible ways to attack the problem.
Clustering algorithm for determining community structure in large networks

NASA Astrophysics Data System (ADS)

Pujol, Josep M.; Béjar, Javier; Delgado, Jordi

2006-07-01

We propose an algorithm to find the community structure in complex networks based on the combination of spectral analysis and modularity optimization. The clustering produced by our algorithm is as accurate as the best algorithms on the literature of modularity optimization; however, the main asset of the algorithm is its efficiency. The best match for our algorithm is Newman’s fast algorithm, which is the reference algorithm for clustering in large networks due to its efficiency. When both algorithms are compared, our algorithm outperforms the fast algorithm both in efficiency and accuracy of the clustering, in terms of modularity. Thus, the results suggest that the proposed algorithm is a good choice to analyze the community structure of medium and large networks in the range of tens and hundreds of thousand vertices.
The human tyrosine kinase Kit and its gatekeeper mutant T670I, show different kinetic properties: Implications for drug design.

PubMed

Kissova, Miroslava; Maga, Giovanni; Crespan, Emmanuele

2016-10-01

The tyrosine kinase Kit, a receptor for Stem Cell Factor, is involved, among others, in processes associated to cell survival, proliferation and migration. Upon physiological conditions, the activity of Kit is tightly regulated. However, primary mutations that lead to its constitutive activation are the causal oncogenic driver of gastrointestinal stromal tumours (GISTs). GISTs are known to be refractory to conventional therapies but the introduction of Imatinib, a selective inhibitor of tyrosine kinases Abl and Kit, significantly ameliorated the treatment options of GISTs patients. However, the acquisition of secondary mutations renders Kit resistant towards all available drugs. Mutation involving gatekeeper residues (such as V654a and T670I) influence both the structure and the catalytic activity of the enzyme. Therefore, detailed knowledge of the enzymatic properties of the mutant forms, in comparison with the wild type enzyme, is an important pre-requisite for the rational development of specific inhibitors. In this paper we report a thorough kinetic analysis of the reaction catalyzed by the Kit kinase and its gatekeeper mutated form T670I. Our results revealed the different mechanisms of action of these two enzymes and may open a new avenue for the future design of specific Kit inhibitors. Copyright © 2016 Elsevier Ltd. All rights reserved.
A community detection algorithm based on structural similarity

NASA Astrophysics Data System (ADS)

Guo, Xuchao; Hao, Xia; Liu, Yaqiong; Zhang, Li; Wang, Lu

2017-09-01

In order to further improve the efficiency and accuracy of community detection algorithm, a new algorithm named SSTCA (the community detection algorithm based on structural similarity with threshold) is proposed. In this algorithm, the structural similarities are taken as the weights of edges, and the threshold k is considered to remove multiple edges whose weights are less than the threshold, and improve the computational efficiency. Tests were done on the Zachary’s network, Dolphins’ social network and Football dataset by the proposed algorithm, and compared with GN and SSNCA algorithm. The results show that the new algorithm is superior to other algorithms in accuracy for the dense networks and the operating efficiency is improved obviously.
Effectiveness of adolescent suicide prevention e-learning modules that aim to improve knowledge and self-confidence of gatekeepers: study protocol for a randomized controlled trial.

PubMed

Ghoncheh, Rezvan; Kerkhof, Ad J F M; Koot, Hans M

2014-02-08

Providing e-learning modules can be an effective strategy for enhancing gatekeepers' knowledge, self-confidence and skills in adolescent suicide prevention. The aim of this study was to test the effectiveness of an online training program called Mental Health Online which consists of eight short e-learning modules, each capturing an important aspect of the process of recognition, guidance and referral of suicidal adolescents (12-20 years). The primary outcomes of this study are participant's ratings on perceived knowledge, perceived self-confidence, and actual knowledge regarding adolescent suicidality. A randomized controlled trial will be carried out among 154 gatekeepers. After completing the first assessment (pre-test), participants will be randomly assigned to either the experimental group or the waitlist control group. One week after completing the first assessment the experimental group will have access to the website Mental Health Online containing the eight e-learning modules and additional information on adolescent suicide prevention. Participants in both conditions will be assessed 4 weeks after completing the first assessment (post-test), and 12 weeks after completing the post-test (follow-up). At post-test, participants from the experimental group are asked to complete an evaluation questionnaire on the modules. The waitlist control group will have access to the modules and additional information on the website after completing the follow-up assessment. Gatekeepers can benefit from e-learning modules on adolescent suicide prevention. This approach allows them to learn about this sensitive subject at their own pace and from any given location, as long as they have access to the Internet. Given the flexible nature of the program, each participant can compose his/her own training creating an instant customized course with the required steps in adolescent suicide prevention. Netherlands Trial Register NTR3625.
Comparison of l₁-Norm SVR and Sparse Coding Algorithms for Linear Regression.

PubMed

Zhang, Qingtian; Hu, Xiaolin; Zhang, Bo

2015-08-01

Support vector regression (SVR) is a popular function estimation technique based on Vapnik's concept of support vector machine. Among many variants, the l1-norm SVR is known to be good at selecting useful features when the features are redundant. Sparse coding (SC) is a technique widely used in many areas and a number of efficient algorithms are available. Both l1-norm SVR and SC can be used for linear regression. In this brief, the close connection between the l1-norm SVR and SC is revealed and some typical algorithms are compared for linear regression. The results show that the SC algorithms outperform the Newton linear programming algorithm, an efficient l1-norm SVR algorithm, in efficiency. The algorithms are then used to design the radial basis function (RBF) neural networks. Experiments on some benchmark data sets demonstrate the high efficiency of the SC algorithms. In particular, one of the SC algorithms, the orthogonal matching pursuit is two orders of magnitude faster than a well-known RBF network designing algorithm, the orthogonal least squares algorithm.
A Coherent VLSI Environment

DTIC Science & Technology

1987-03-31

processors . The symmetry-breaking algorithms give efficient ways to convert probabilistic algorithms to deterministic algorithms. Some of the...techniques have been applied to construct several efficient linear- processor algorithms for graph problems, including an O(lg* n)-time algorithm for (A + 1...On n-node graphs, the algorithm works in O(log 2 n) time using only n processors , in contrast to the previous best algorithm which used about n3
CCOMP: An efficient algorithm for complex roots computation of determinantal equations

NASA Astrophysics Data System (ADS)

Zouros, Grigorios P.

2018-01-01

In this paper a free Python algorithm, entitled CCOMP (Complex roots COMPutation), is developed for the efficient computation of complex roots of determinantal equations inside a prescribed complex domain. The key to the method presented is the efficient determination of the candidate points inside the domain which, in their close neighborhood, a complex root may lie. Once these points are detected, the algorithm proceeds to a two-dimensional minimization problem with respect to the minimum modulus eigenvalue of the system matrix. In the core of CCOMP exist three sub-algorithms whose tasks are the efficient estimation of the minimum modulus eigenvalues of the system matrix inside the prescribed domain, the efficient computation of candidate points which guarantee the existence of minima, and finally, the computation of minima via bound constrained minimization algorithms. Theoretical results and heuristics support the development and the performance of the algorithm, which is discussed in detail. CCOMP supports general complex matrices, and its efficiency, applicability and validity is demonstrated to a variety of microwave applications.
On the development of efficient algorithms for three dimensional fluid flow

NASA Technical Reports Server (NTRS)

Maccormack, R. W.

1988-01-01

The difficulties of constructing efficient algorithms for three-dimensional flow are discussed. Reasonable candidates are analyzed and tested, and most are found to have obvious shortcomings. Yet, there is promise that an efficient class of algorithms exist between the severely time-step sized-limited explicit or approximately factored algorithms and the computationally intensive direct inversion of large sparse matrices by Gaussian elimination.
Migrating from user fees to social health insurance: exploring the prospects and challenges for hospital management

PubMed Central

2012-01-01

Background In 2003 Ghana introduced a social health insurance scheme which resulted in the separation of purchasing of health services by the health insurance authority on the one hand and the provision of health services by hospitals at the other side of the spectrum. This separation has a lot of implications for managing accredited hospitals. This paper examines whether decoupling purchasing and service provision translate into opportunities or challenges in the management of accredited hospitals. Methods A qualitative exploratory study of 15 accredited district hospitals were selected from five of Ghana’s ten administrative regions for the study. A semi-structured interview guide was designed to solicit information from key informants, Health Service Administrators, Pharmacists, Accountants and Scheme Managers of the hospitals studied. Data was analysed thematically. Results The results showed that under the health insurance scheme, hospitals are better-off in terms of cash flow and adequate stock levels of drugs. Adequate stock of non-drugs under the scheme was reportedly intermittent. The major challenges confronting the hospitals were identified as weak purchasing power due to low tariffs, non computerisation of claims processing, unpredictable payment pattern, poor gate-keeping systems, lack of logistics and other new and emerging challenges relating to moral hazards and the use of false identity cards under pretence for medical care. Conclusion Study’s findings have a lot of policy implications for proper management of hospitals. The findings suggest rationalisation of the current tariff structure, the application of contract based payment system to inject efficiency into hospitals management and piloting facility based vetting systems to offset vetting loads of the insurance authority. Proper gate-keeping mechanisms are also needed to curtail the phenomenon of moral hazard and false documentation. PMID:22726666
Migrating from user fees to social health insurance: exploring the prospects and challenges for hospital management.

PubMed

Atinga, Roger A; Mensah, Sylvester A; Asenso-Boadi, Francis; Adjei, Francis-Xavier Andoh

2012-06-22

In 2003 Ghana introduced a social health insurance scheme which resulted in the separation of purchasing of health services by the health insurance authority on the one hand and the provision of health services by hospitals at the other side of the spectrum. This separation has a lot of implications for managing accredited hospitals. This paper examines whether decoupling purchasing and service provision translate into opportunities or challenges in the management of accredited hospitals. A qualitative exploratory study of 15 accredited district hospitals were selected from five of Ghana's ten administrative regions for the study. A semi-structured interview guide was designed to solicit information from key informants, Health Service Administrators, Pharmacists, Accountants and Scheme Managers of the hospitals studied. Data was analysed thematically. The results showed that under the health insurance scheme, hospitals are better-off in terms of cash flow and adequate stock levels of drugs. Adequate stock of non-drugs under the scheme was reportedly intermittent. The major challenges confronting the hospitals were identified as weak purchasing power due to low tariffs, non computerisation of claims processing, unpredictable payment pattern, poor gate-keeping systems, lack of logistics and other new and emerging challenges relating to moral hazards and the use of false identity cards under pretence for medical care. Study's findings have a lot of policy implications for proper management of hospitals. The findings suggest rationalisation of the current tariff structure, the application of contract based payment system to inject efficiency into hospitals management and piloting facility based vetting systems to offset vetting loads of the insurance authority. Proper gate-keeping mechanisms are also needed to curtail the phenomenon of moral hazard and false documentation.
An efficient quantum algorithm for spectral estimation

NASA Astrophysics Data System (ADS)

Steffens, Adrian; Rebentrost, Patrick; Marvian, Iman; Eisert, Jens; Lloyd, Seth

2017-03-01

We develop an efficient quantum implementation of an important signal processing algorithm for line spectral estimation: the matrix pencil method, which determines the frequencies and damping factors of signals consisting of finite sums of exponentially damped sinusoids. Our algorithm provides a quantum speedup in a natural regime where the sampling rate is much higher than the number of sinusoid components. Along the way, we develop techniques that are expected to be useful for other quantum algorithms as well—consecutive phase estimations to efficiently make products of asymmetric low rank matrices classically accessible and an alternative method to efficiently exponentiate non-Hermitian matrices. Our algorithm features an efficient quantum-classical division of labor: the time-critical steps are implemented in quantum superposition, while an interjacent step, requiring much fewer parameters, can operate classically. We show that frequencies and damping factors can be obtained in time logarithmic in the number of sampling points, exponentially faster than known classical algorithms.
Efficient algorithms for single-axis attitude estimation

NASA Technical Reports Server (NTRS)

Shuster, M. D.

1981-01-01

The computationally efficient algorithms determine attitude from the measurement of art lengths and dihedral angles. The dependence of these algorithms on the solution of trigonometric equations was reduced. Both single time and batch estimators are presented along with the covariance analysis of each algorithm.
Polydopamine-like Coatings as Payload Gatekeepers for Mesoporous Silica Nanoparticles.

PubMed

Moreno-Villaécija, Miguel-Ángel; Sedó-Vegara, Josep; Guisasola, Eduardo; Baeza, Alejandro; Regí, María Vallet; Nador, Fabiana; Ruiz-Molina, Daniel

2018-03-07

We report the use of bis-catecholic polymers as candidates for obtaining effective, tunable gatekeeping coatings for mesoporous silica nanoparticles (MSNs) intended for drug release applications. In monomers, catechol rings act as adhesive moieties and reactive sites for polymerization, together with middle linkers which may be chosen to tune the physicochemical properties of the resulting coating. Stable and low-toxicity coatings (pNDGA and pBHZ) were prepared from two bis-catechols of different polarity (NDGA and BHZ) on MSN carriers previously loaded with rhodamine B (RhB) as a model payload, by means of a previously reported synthetic methodology and without any previous surface modification. Coating robustness and payload content were shown to depend significantly on the workup protocol. The release profiles in a model physiological PBS buffer of coated systems (RhB@MSN@pNDGA and RhB@MSN@pBHZ) showed marked differences in the "gatekeeping" behavior of each coating, which correlated qualitatively with the chemical nature of their respective linker moieties. While the uncoated system (RhB@MSN) lost its payload almost completely after 2 days, release from RhB@MSN@pNDGA was virtually negligible, likely due to the low polarity of the parent bis-catechol (NDGA). As opposed to these extremes, RhB@MSN@pBHZ presented the most promising behavior, showing an intermediate release of 50% of the payload in the same period of time.
Joint marketing as a framework for targeting men who have sex with men in China: a pilot intervention study.

PubMed

Tan, Jingguang; Cai, Rui; Lu, Zuxun; Cheng, Jinquan; de Vlas, Sake J; Richardus, Jan Hendrik

2013-04-01

To apply the joint marketing principle as a new intervention approach for targeting men who have sex with men (MSM) who are often difficult to reach in societies with discrimination towards homosexuality and HIV/AIDS. A pilot intervention according to the principles of joint marketing was carried out by the CDC in Shenzhen, China, in MSM social venues. A self-designed questionnaire of HIV knowledge, condom use, and access to HIV-related services was used before and after the pilot intervention to evaluate its effectiveness. The CDC supported gatekeepers of MSM social venues in running their business and thereby increasing their respectability and income. In return, the gatekeepers cooperated with the CDC in reaching the MSM at the venues with health promotion messages and materials. Thus a win-win situation was created, bringing together two noncompetitive parties in reaching out to a shared customer, the MSM. The pilot intervention succeeded in demonstrating acceptability and feasibility of the joint marketing approach targeting MSM. HIV knowledge, the rate of condom use, and access to HIV-related services of participants in the pilot intervention increased significantly. The joint marketing intervention is an innovative way to create synergies between the gatekeepers of MSM social venues and public health officials for reaching and potentially changing HIV high-risk behaviors among MSM.
Spatiotemporally and Sequentially-Controlled Drug Release from Polymer Gatekeeper-Hollow Silica Nanoparticles

NASA Astrophysics Data System (ADS)

Palanikumar, L.; Jeena, M. T.; Kim, Kibeom; Yong Oh, Jun; Kim, Chaekyu; Park, Myoung-Hwan; Ryu, Ja-Hyoung

2017-04-01

Combination chemotherapy has become the primary strategy against cancer multidrug resistance; however, accomplishing optimal pharmacokinetic delivery of multiple drugs is still challenging. Herein, we report a sequential combination drug delivery strategy exploiting a pH-triggerable and redox switch to release cargos from hollow silica nanoparticles in a spatiotemporal manner. This versatile system further enables a large loading efficiency for both hydrophobic and hydrophilic drugs inside the nanoparticles, followed by self-crosslinking with disulfide and diisopropylamine-functionalized polymers. In acidic tumour environments, the positive charge generated by the protonation of the diisopropylamine moiety facilitated the cellular uptake of the particles. Upon internalization, the acidic endosomal pH condition and intracellular glutathione regulated the sequential release of the drugs in a time-dependent manner, providing a promising therapeutic approach to overcoming drug resistance during cancer treatment.
Preparation of a mesoporous silica-based nano-vehicle for dual DOX/CPT pH-triggered delivery.

PubMed

Llinàs, Maria C; Martínez-Edo, Gabriel; Cascante, Anna; Porcar, Irene; Borrós, Salvador; Sánchez-García, David

2018-11-01

A dual doxorubicin/camptothecin (DOX/CPT) pH-triggered drug delivery mesoporous silica nanoparticle (MSN)-based nano-vehicle has been prepared. In this drug-delivery system (DDS), CPT is loaded inside the pores of the MSNs, while DOX is covalently attached to the surface of an aldehyde-functionalized MSN through a dihydrazide-polyethylene glycol chain. Thus, DOX and the linker act as pH-sensitive gatekeeper. The system is versatile and easy to assemble, not requiring the chemical modification of the drugs. While at physiological conditions the release of the drugs is negligible, at acidic pH a burst release of DOX and a gradual release of CPT take place. In vitro cytotoxicity tests have demonstrated that this DDS can deliver efficiently DOX and CPT for combination therapy.
Calibration free beam hardening correction for cardiac CT perfusion imaging

NASA Astrophysics Data System (ADS)

Levi, Jacob; Fahmi, Rachid; Eck, Brendan L.; Fares, Anas; Wu, Hao; Vembar, Mani; Dhanantwari, Amar; Bezerra, Hiram G.; Wilson, David L.

2016-03-01

Myocardial perfusion imaging using CT (MPI-CT) and coronary CTA have the potential to make CT an ideal noninvasive gate-keeper for invasive coronary angiography. However, beam hardening artifacts (BHA) prevent accurate blood flow calculation in MPI-CT. BH Correction (BHC) methods require either energy-sensitive CT, not widely available, or typically a calibration-based method. We developed a calibration-free, automatic BHC (ABHC) method suitable for MPI-CT. The algorithm works with any BHC method and iteratively determines model parameters using proposed BHA-specific cost function. In this work, we use the polynomial BHC extended to three materials. The image is segmented into soft tissue, bone, and iodine images, based on mean HU and temporal enhancement. Forward projections of bone and iodine images are obtained, and in each iteration polynomial correction is applied. Corrections are then back projected and combined to obtain the current iteration's BHC image. This process is iterated until cost is minimized. We evaluate the algorithm on simulated and physical phantom images and on preclinical MPI-CT data. The scans were obtained on a prototype spectral detector CT (SDCT) scanner (Philips Healthcare). Mono-energetic reconstructed images were used as the reference. In the simulated phantom, BH streak artifacts were reduced from 12+/-2HU to 1+/-1HU and cupping was reduced by 81%. Similarly, in physical phantom, BH streak artifacts were reduced from 48+/-6HU to 1+/-5HU and cupping was reduced by 86%. In preclinical MPI-CT images, BHA was reduced from 28+/-6 HU to less than 4+/-4HU at peak enhancement. Results suggest that the algorithm can be used to reduce BHA in conventional CT and improve MPI-CT accuracy.
Efficient spectral-Galerkin algorithms for direct solution for second-order differential equations using Jacobi polynomials

NASA Astrophysics Data System (ADS)

Doha, E.; Bhrawy, A.

2006-06-01

It is well known that spectral methods (tau, Galerkin, collocation) have a condition number of ( is the number of retained modes of polynomial approximations). This paper presents some efficient spectral algorithms, which have a condition number of , based on the Jacobi?Galerkin methods of second-order elliptic equations in one and two space variables. The key to the efficiency of these algorithms is to construct appropriate base functions, which lead to systems with specially structured matrices that can be efficiently inverted. The complexities of the algorithms are a small multiple of operations for a -dimensional domain with unknowns, while the convergence rates of the algorithms are exponentials with smooth solutions.
Spectral compression algorithms for the analysis of very large multivariate images

DOEpatents

Keenan, Michael R.

2007-10-16

A method for spectrally compressing data sets enables the efficient analysis of very large multivariate images. The spectral compression algorithm uses a factored representation of the data that can be obtained from Principal Components Analysis or other factorization technique. Furthermore, a block algorithm can be used for performing common operations more efficiently. An image analysis can be performed on the factored representation of the data, using only the most significant factors. The spectral compression algorithm can be combined with a spatial compression algorithm to provide further computational efficiencies.

A scalable parallel algorithm for multiple objective linear programs

NASA Technical Reports Server (NTRS)

Wiecek, Malgorzata M.; Zhang, Hong

1994-01-01

This paper presents an ADBASE-based parallel algorithm for solving multiple objective linear programs (MOLP's). Job balance, speedup and scalability are of primary interest in evaluating efficiency of the new algorithm. Implementation results on Intel iPSC/2 and Paragon multiprocessors show that the algorithm significantly speeds up the process of solving MOLP's, which is understood as generating all or some efficient extreme points and unbounded efficient edges. The algorithm gives specially good results for large and very large problems. Motivation and justification for solving such large MOLP's are also included.
Efficient conjugate gradient algorithms for computation of the manipulator forward dynamics

NASA Technical Reports Server (NTRS)

Fijany, Amir; Scheid, Robert E.

1989-01-01

The applicability of conjugate gradient algorithms for computation of the manipulator forward dynamics is investigated. The redundancies in the previously proposed conjugate gradient algorithm are analyzed. A new version is developed which, by avoiding these redundancies, achieves a significantly greater efficiency. A preconditioned conjugate gradient algorithm is also presented. A diagonal matrix whose elements are the diagonal elements of the inertia matrix is proposed as the preconditioner. In order to increase the computational efficiency, an algorithm is developed which exploits the synergism between the computation of the diagonal elements of the inertia matrix and that required by the conjugate gradient algorithm.
Multicore and GPU algorithms for Nussinov RNA folding

PubMed Central

2014-01-01

Background One segment of a RNA sequence might be paired with another segment of the same RNA sequence due to the force of hydrogen bonds. This two-dimensional structure is called the RNA sequence's secondary structure. Several algorithms have been proposed to predict an RNA sequence's secondary structure. These algorithms are referred to as RNA folding algorithms. Results We develop cache efficient, multicore, and GPU algorithms for RNA folding using Nussinov's algorithm. Conclusions Our cache efficient algorithm provides a speedup between 1.6 and 3.0 relative to a naive straightforward single core code. The multicore version of the cache efficient single core algorithm provides a speedup, relative to the naive single core algorithm, between 7.5 and 14.0 on a 6 core hyperthreaded CPU. Our GPU algorithm for the NVIDIA C2050 is up to 1582 times as fast as the naive single core algorithm and between 5.1 and 11.2 times as fast as the fastest previously known GPU algorithm for Nussinov RNA folding. PMID:25082539
Hybrid Particle Swarm Optimization for Hybrid Flowshop Scheduling Problem with Maintenance Activities

PubMed Central

Li, Jun-qing; Pan, Quan-ke; Mao, Kun

2014-01-01

A hybrid algorithm which combines particle swarm optimization (PSO) and iterated local search (ILS) is proposed for solving the hybrid flowshop scheduling (HFS) problem with preventive maintenance (PM) activities. In the proposed algorithm, different crossover operators and mutation operators are investigated. In addition, an efficient multiple insert mutation operator is developed for enhancing the searching ability of the algorithm. Furthermore, an ILS-based local search procedure is embedded in the algorithm to improve the exploitation ability of the proposed algorithm. The detailed experimental parameter for the canonical PSO is tuning. The proposed algorithm is tested on the variation of 77 Carlier and Néron's benchmark problems. Detailed comparisons with the present efficient algorithms, including hGA, ILS, PSO, and IG, verify the efficiency and effectiveness of the proposed algorithm. PMID:24883414
Computationally efficient multibody simulations

NASA Technical Reports Server (NTRS)

Ramakrishnan, Jayant; Kumar, Manoj

1994-01-01

Computationally efficient approaches to the solution of the dynamics of multibody systems are presented in this work. The computational efficiency is derived from both the algorithmic and implementational standpoint. Order(n) approaches provide a new formulation of the equations of motion eliminating the assembly and numerical inversion of a system mass matrix as required by conventional algorithms. Computational efficiency is also gained in the implementation phase by the symbolic processing and parallel implementation of these equations. Comparison of this algorithm with existing multibody simulation programs illustrates the increased computational efficiency.
Beam-steering efficiency optimization method based on a rapid-search algorithm for liquid crystal optical phased array.

PubMed

Xiao, Feng; Kong, Lingjiang; Chen, Jian

2017-06-01

A rapid-search algorithm to improve the beam-steering efficiency for a liquid crystal optical phased array was proposed and experimentally demonstrated in this paper. This proposed algorithm, in which the value of steering efficiency is taken as the objective function and the controlling voltage codes are considered as the optimization variables, consisted of a detection stage and a construction stage. It optimized the steering efficiency in the detection stage and adjusted its search direction adaptively in the construction stage to avoid getting caught in a wrong search space. Simulations had been conducted to compare the proposed algorithm with the widely used pattern-search algorithm using criteria of convergence rate and optimized efficiency. Beam-steering optimization experiments had been performed to verify the validity of the proposed method.
A Fast parallel tridiagonal algorithm for a class of CFD applications

NASA Technical Reports Server (NTRS)

Moitra, Stuti; Sun, Xian-He

1996-01-01

The parallel diagonal dominant (PDD) algorithm is an efficient tridiagonal solver. This paper presents for study a variation of the PDD algorithm, the reduced PDD algorithm. The new algorithm maintains the minimum communication provided by the PDD algorithm, but has a reduced operation count. The PDD algorithm also has a smaller operation count than the conventional sequential algorithm for many applications. Accuracy analysis is provided for the reduced PDD algorithm for symmetric Toeplitz tridiagonal (STT) systems. Implementation results on Langley's Intel Paragon and IBM SP2 show that both the PDD and reduced PDD algorithms are efficient and scalable.
Denni Algorithm An Enhanced Of SMS (Scan, Move and Sort) Algorithm

NASA Astrophysics Data System (ADS)

Aprilsyah Lubis, Denni; Salim Sitompul, Opim; Marwan; Tulus; Andri Budiman, M.

2017-12-01

Sorting has been a profound area for the algorithmic researchers, and many resources are invested to suggest a more working sorting algorithm. For this purpose many existing sorting algorithms were observed in terms of the efficiency of the algorithmic complexity. Efficient sorting is important to optimize the use of other algorithms that require sorted lists to work correctly. Sorting has been considered as a fundamental problem in the study of algorithms that due to many reasons namely, the necessary to sort information is inherent in many applications, algorithms often use sorting as a key subroutine, in algorithm design there are many essential techniques represented in the body of sorting algorithms, and many engineering issues come to the fore when implementing sorting algorithms., Many algorithms are very well known for sorting the unordered lists, and one of the well-known algorithms that make the process of sorting to be more economical and efficient is SMS (Scan, Move and Sort) algorithm, an enhancement of Quicksort invented Rami Mansi in 2010. This paper presents a new sorting algorithm called Denni-algorithm. The Denni algorithm is considered as an enhancement on the SMS algorithm in average, and worst cases. The Denni algorithm is compared with the SMS algorithm and the results were promising.
Optimal Fungal Space Searching Algorithms.

PubMed

Asenova, Elitsa; Lin, Hsin-Yu; Fu, Eileen; Nicolau, Dan V; Nicolau, Dan V

2016-10-01

Previous experiments have shown that fungi use an efficient natural algorithm for searching the space available for their growth in micro-confined networks, e.g., mazes. This natural "master" algorithm, which comprises two "slave" sub-algorithms, i.e., collision-induced branching and directional memory, has been shown to be more efficient than alternatives, with one, or the other, or both sub-algorithms turned off. In contrast, the present contribution compares the performance of the fungal natural algorithm against several standard artificial homologues. It was found that the space-searching fungal algorithm consistently outperforms uninformed algorithms, such as Depth-First-Search (DFS). Furthermore, while the natural algorithm is inferior to informed ones, such as A*, this under-performance does not importantly increase with the increase of the size of the maze. These findings suggest that a systematic effort of harvesting the natural space searching algorithms used by microorganisms is warranted and possibly overdue. These natural algorithms, if efficient, can be reverse-engineered for graph and tree search strategies.
Spatial compression algorithm for the analysis of very large multivariate images

DOEpatents

Keenan, Michael R [Albuquerque, NM

2008-07-15

A method for spatially compressing data sets enables the efficient analysis of very large multivariate images. The spatial compression algorithms use a wavelet transformation to map an image into a compressed image containing a smaller number of pixels that retain the original image's information content. Image analysis can then be performed on a compressed data matrix consisting of a reduced number of significant wavelet coefficients. Furthermore, a block algorithm can be used for performing common operations more efficiently. The spatial compression algorithms can be combined with spectral compression algorithms to provide further computational efficiencies.
Efficient FFT Algorithm for Psychoacoustic Model of the MPEG-4 AAC

NASA Astrophysics Data System (ADS)

Lee, Jae-Seong; Lee, Chang-Joon; Park, Young-Cheol; Youn, Dae-Hee

This paper proposes an efficient FFT algorithm for the Psycho-Acoustic Model (PAM) of MPEG-4 AAC. The proposed algorithm synthesizes FFT coefficients using MDCT and MDST coefficients through circular convolution. The complexity of the MDCT and MDST coefficients is approximately half of the original FFT. We also design a new PAM based on the proposed FFT algorithm, which has 15% lower computational complexity than the original PAM without degradation of sound quality. Subjective as well as objective test results are presented to confirm the efficiency of the proposed FFT computation algorithm and the PAM.
A New Algorithm Using the Non-Dominated Tree to Improve Non-Dominated Sorting.

PubMed

Gustavsson, Patrik; Syberfeldt, Anna

2018-01-01

Non-dominated sorting is a technique often used in evolutionary algorithms to determine the quality of solutions in a population. The most common algorithm is the Fast Non-dominated Sort (FNS). This algorithm, however, has the drawback that its performance deteriorates when the population size grows. The same drawback applies also to other non-dominating sorting algorithms such as the Efficient Non-dominated Sort with Binary Strategy (ENS-BS). An algorithm suggested to overcome this drawback is the Divide-and-Conquer Non-dominated Sort (DCNS) which works well on a limited number of objectives but deteriorates when the number of objectives grows. This article presents a new, more efficient algorithm called the Efficient Non-dominated Sort with Non-Dominated Tree (ENS-NDT). ENS-NDT is an extension of the ENS-BS algorithm and uses a novel Non-Dominated Tree (NDTree) to speed up the non-dominated sorting. ENS-NDT is able to handle large population sizes and a large number of objectives more efficiently than existing algorithms for non-dominated sorting. In the article, it is shown that with ENS-NDT the runtime of multi-objective optimization algorithms such as the Non-Dominated Sorting Genetic Algorithm II (NSGA-II) can be substantially reduced.
Finding minimum spanning trees more efficiently for tile-based phase unwrapping

NASA Astrophysics Data System (ADS)

Sawaf, Firas; Tatam, Ralph P.

2006-06-01

The tile-based phase unwrapping method employs an algorithm for finding the minimum spanning tree (MST) in each tile. We first examine the properties of a tile's representation from a graph theory viewpoint, observing that it is possible to make use of a more efficient class of MST algorithms. We then describe a novel linear time algorithm which reduces the size of the MST problem by half at the least, and solves it completely at best. We also show how this algorithm can be applied to a tile using a sliding window technique. Finally, we show how the reduction algorithm can be combined with any other standard MST algorithm to achieve a more efficient hybrid, using Prim's algorithm for empirical comparison and noting that the reduction algorithm takes only 0.1% of the time taken by the overall hybrid.
Druggists and pharmacists as gatekeepers: sales routines and compliance with sales protocols for over-the-counter naproxen 275 mg medicines in the Netherlands.

PubMed

van Hoof, Joris J; Cents, Michel H G; Megens, Nicole M J; van der Tang, Sijbrand J

2014-09-01

Since for the sales of over-the-counter (OTC) medicines, prescribing physicians are not involved, and written instructions on/in the medicine boxes are inefficient, druggists and pharmacists are important gatekeepers in preventing customers' accidents. In this study we investigated the sales routines, and compliance with sales protocols, in order to evaluate that gatekeeper's function. By means of the mystery shopping method, 228 pharmacies and drugstores in The Netherlands were visited and a naproxen 275mg medium-risk medicine was requested for a (fictitious) patient who was suffering from severe back pains. According to the sales protocols the vendors should never sell the requested medicine, because the mystery shoppers only gave an answer to one of the four mandatory sales protocol questions. Furthermore, the requested medicine is not the right or best choice for back pains. Four different scenarios were used in a 2×2 design (8-year-old patient vs. 25-year-old patient, and 1 box with 12 pills vs. 3 boxes with 12 pills). Of the drugstores and pharmacies only 16.7% complied with the sales protocols and did not sell the specific (or comparable) medicine, after asking all four mandatory questions (or already after one, two or three questions). Most vendors (83.3%) did not comply and sold the requested medicine, a comparable medicine, or even a more risky medicine after no question at all (or after asking some or even all four questions). Although both score low, pharmacists show better compliance (23.9%) than druggists (10.1%). When it comes to OTC medicines, druggists and pharmacists largely commit sloppy sales. The expected gatekeeping function of pharmacists and druggists is very limited, and customers might be in danger of inappropriate medicine selection, quantity and usage. We call for thorough evaluation of the over-the-counter system, improvement of the educational programs for medicine providers, and national campaigns to inform the public. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.
Trellises and Trellis-Based Decoding Algorithms for Linear Block Codes. Part 3; A Recursive Maximum Likelihood Decoding

NASA Technical Reports Server (NTRS)

Lin, Shu; Fossorier, Marc

1998-01-01

The Viterbi algorithm is indeed a very simple and efficient method of implementing the maximum likelihood decoding. However, if we take advantage of the structural properties in a trellis section, other efficient trellis-based decoding algorithms can be devised. Recently, an efficient trellis-based recursive maximum likelihood decoding (RMLD) algorithm for linear block codes has been proposed. This algorithm is more efficient than the conventional Viterbi algorithm in both computation and hardware requirements. Most importantly, the implementation of this algorithm does not require the construction of the entire code trellis, only some special one-section trellises of relatively small state and branch complexities are needed for constructing path (or branch) metric tables recursively. At the end, there is only one table which contains only the most likely code-word and its metric for a given received sequence r = (r(sub 1), r(sub 2),...,r(sub n)). This algorithm basically uses the divide and conquer strategy. Furthermore, it allows parallel/pipeline processing of received sequences to speed up decoding.
A clinical case-based hypothesis: secretory IgA operates as an electronic transistor controlling the selection or rejection of molecules in the absorption process in the lumen of gastrointestinal tract

PubMed Central

Zamm, Alfred V

2013-01-01

There is a clinical correlation between (1) an allergic patient’s ability to resist the development of symptoms that would have resulted from an allergenic challenge, (2) the magnitude of geomagnetism at a geographic site, and (3) the amount of solar energy falling on that site. It is suggested that the digestive membrane has an electronic gatekeeper that “decides” electronically which molecules to allow or not allow to pass on to the absorptive surface. The unique bipolar structure of secretory immunoglobulin A (IgA), having a central secretory piece and the resultant unique electronic function of this polarized molecule, allows it to function as an electronic transistor, producing an electronic gatekeeper in the form of an electronic sieve. PMID:24068871
A clinical case-based hypothesis: secretory IgA operates as an electronic transistor controlling the selection or rejection of molecules in the absorption process in the lumen of gastrointestinal tract.

PubMed

Zamm, Alfred V

2013-01-01

There is a clinical correlation between (1) an allergic patient's ability to resist the development of symptoms that would have resulted from an allergenic challenge, (2) the magnitude of geomagnetism at a geographic site, and (3) the amount of solar energy falling on that site. It is suggested that the digestive membrane has an electronic gatekeeper that "decides" electronically which molecules to allow or not allow to pass on to the absorptive surface. The unique bipolar structure of secretory immunoglobulin A (IgA), having a central secretory piece and the resultant unique electronic function of this polarized molecule, allows it to function as an electronic transistor, producing an electronic gatekeeper in the form of an electronic sieve.
Discovery of 5-(arenethynyl) hetero-monocyclic derivatives as potent inhibitors of BCR-ABL including the T315I gatekeeper mutant.

PubMed

Thomas, Mathew; Huang, Wei-Sheng; Wen, David; Zhu, Xiaotian; Wang, Yihan; Metcalf, Chester A; Liu, Shuangying; Chen, Ingrid; Romero, Jan; Zou, Dong; Sundaramoorthi, Raji; Li, Feng; Qi, Jiwei; Cai, Lisi; Zhou, Tianjun; Commodore, Lois; Xu, Qihong; Keats, Jeff; Wang, Frank; Wardwell, Scott; Ning, Yaoyu; Snodgrass, Joseph T; Broudy, Marc I; Russian, Karin; Iuliucci, John; Rivera, Victor M; Sawyer, Tomi K; Dalgarno, David C; Clackson, Tim; Shakespeare, William C

2011-06-15

Ponatinib (AP24534) was previously identified as a pan-BCR-ABL inhibitor that potently inhibits the T315I gatekeeper mutant, and has advanced into clinical development for the treatment of refractory or resistant CML. In this study, we explored a novel series of five and six membered monocycles as alternate hinge-binding templates to replace the 6,5-fused imidazopyridazine core of ponatinib. Like ponatinib, these monocycles are tethered to pendant toluanilides via an ethynyl linker. Several compounds in this series displayed excellent in vitro potency against both native BCR-ABL and the T315I mutant. Notably, a subset of inhibitors exhibited desirable PK and were orally active in a mouse model of T315I-driven CML. Copyright © 2011 Elsevier Ltd. All rights reserved.
Direct Substrate Identification with an Analog Sensitive (AS) Viral Cyclin-Dependent Kinase (v-Cdk).

PubMed

Umaña, Angie C; Iwahori, Satoko; Kalejta, Robert F

2018-01-19

Viral cyclin-dependent kinases (v-Cdks) functionally emulate their cellular Cdk counterparts. Such viral mimicry is an established phenomenon that we extend here through chemical genetics. Kinases contain gatekeeper residues that limit the size of molecules that can be accommodated within the enzyme active site. Mutating gatekeeper residues to smaller amino acids allows larger molecules access to the active site. Such mutants can utilize bio-orthoganol ATPs for phosphate transfer and are inhibited by compounds ineffective against the wild type protein, and thus are referred to as analog-sensitive (AS) kinases. We identified the gatekeeper residues of the v-Cdks encoded by Epstein-Barr virus (EBV) and human cytomegalovirus (HCMV) and mutated them to generate AS kinases. The AS-v-Cdks are functional and utilize different ATP derivatives with a specificity closely matching their cellular ortholog, AS-Cdk2. The AS derivative of the EBV v-Cdk was used to transfer a thiolated phosphate group to targeted proteins which were then purified through covalent capture and identified by mass spectrometry. Pathway analysis of these newly identified direct substrates of the EBV v-Cdk extends the potential influence of this kinase into all stages of gene expression (transcription, splicing, mRNA export, and translation). Our work demonstrates the biochemical similarity of the cellular and viral Cdks, as well as the utility of AS v-Cdks for substrate identification to increase our understanding of both viral infections and Cdk biology.
The Importance of a Gatekeeper Residue on the Aggregation of Transthyretin

PubMed Central

Sant'Anna, Ricardo; Braga, Carolina; Varejão, Nathalia; Pimenta, Karinne M.; Graña-Montes, Ricardo; Alves, Aline; Cortines, Juliana; Cordeiro, Yraima; Ventura, Salvador; Foguel, Debora

2014-01-01

Protein aggregation into β-sheet-enriched amyloid fibrils is associated with an increasing number of human disorders. The adoption of such amyloid conformations seems to constitute a generic property of polypeptide chains. Therefore, during evolution, proteins have adopted negative design strategies to diminish their intrinsic propensity to aggregate, including enrichment of gatekeeper charged residues at the flanks of hydrophobic aggregation-prone segments. Wild type transthyretin (TTR) is responsible for senile systemic amyloidosis, and more than 100 mutations in the TTR gene are involved in familial amyloid polyneuropathy. The TTR 26–57 segment bears many of these aggressive amyloidogenic mutations as well as the binding site for heparin. We demonstrate here that Lys-35 acts as a gatekeeper residue in TTR, strongly decreasing its amyloidogenic potential. This protective effect is sequence-specific because Lys-48 does not affect TTR aggregation. Lys-35 is part of the TTR basic heparin-binding motif. This glycosaminoglycan blocks the protective effect of Lys-35, probably by neutralization of its side chain positive charge. A K35L mutation emulates this effect and results in the rapid self-assembly of the TTR 26–57 region into amyloid fibrils. This mutation does not affect the tetrameric protein stability, but it strongly increases its aggregation propensity. Overall, we illustrate how TTR is yet another amyloidogenic protein exploiting negative design to prevent its massive aggregation, and we show how blockage of conserved protective features by endogenous factors or mutations might result in increased disease susceptibility. PMID:25086037

Absorptive capacity as a guiding concept for effective public sector management and conservation of freshwater ecosystems.

PubMed

Murray, K; Roux, D J; Nel, J L; Driver, A; Freimund, W

2011-05-01

The ability of an organisation to recognise the value of new external information, acquire it, assimilate it, transform, and exploit it, namely its absorptive capacity (AC), has been much researched in the context of commercial organisations and even applied to national innovation. This paper considers four key AC-related concepts and their relevance to public sector organisations with mandates to manage and conserve freshwater ecosystems for the common good. The concepts are the importance of in-house prior related knowledge, the importance of informal knowledge transfer, the need for motivation and intensity of effort, and the importance of gatekeepers. These concepts are used to synthesise guidance for a way forward in respect of such freshwater management and conservation, using the imminent release of a specific scientific conservation planning and management tool in South Africa as a case study. The tool comprises a comprehensive series of maps that depict national freshwater ecosystem priority areas for South Africa. Insights for implementing agencies relate to maintaining an internal science, rather than research capacity; making unpublished and especially tacit knowledge available through informal knowledge transfer; not underestimating the importance of intensity of effort required to create AC, driven by focussed motivation; and the potential use of a gatekeeper at national level (external to the implementing organisations), possibly playing a more general 'bridging' role, and multiple internal (organisational) gatekeepers playing the more limited role of 'knowledge translators'. The role of AC as a unifying framework is also proposed.
The role of primary care physicians in the Israel Defense Forces: a self-perception study.

PubMed

Zimlichman, Eyal; Mandel, Dror; Mimouni, Francis B; Vinker, Shlomo; Kochba, Ilan; Kreiss, Yitshak; Lahad, Amnon

2005-03-01

The health system of the medical corps of the Israel Defense Force is based primarily upon primary healthcare. In recent years, health management organizations have considered the primary care physician responsible for assessing the overall health needs of the patient and, accordingly, introduced the term "gatekeeper." To describe and analyze how PCPs in the IDF view their roles as primary care providers and to characterize how they perceive the quality of the medical care that they provide. We conducted a survey using a questionnaire that was mailed or faxed to a representative sample of PCPs. The questionnaire included demographic background, professional background, statements on self-perception issues, and ranking of roles as a PCP in the IDF. Statements concerning commitment to the patient were ranked higher than statements concerning commitment to the military organization. Most physicians perceive the quality of the medical care service that they provide as high; they also stated that they do not receive adequate continuous medical education. Our survey shows that PCPs in the IDF, like civilian family physicians, perceive their primary obligation as serving the needs of their patients but are yet to take on the full role of "gatekeepers" in the IDF's healthcare system. We conclude that the Medical Corps should implement appropriate steps to ensure that PCPs are prepared to take on a more prominent role as "gatekeepers" and providers of high quality primary medical care.
Efficient block preconditioned eigensolvers for linear response time-dependent density functional theory

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

Vecharynski, Eugene; Brabec, Jiri; Shao, Meiyue

We present two efficient iterative algorithms for solving the linear response eigen- value problem arising from the time dependent density functional theory. Although the matrix to be diagonalized is nonsymmetric, it has a special structure that can be exploited to save both memory and floating point operations. In particular, the nonsymmetric eigenvalue problem can be transformed into a product eigenvalue problem that is self-adjoint with respect to a K-inner product. This product eigenvalue problem can be solved efficiently by a modified Davidson algorithm and a modified locally optimal block preconditioned conjugate gradient (LOBPCG) algorithm that make use of the K-innermore » product. The solution of the product eigenvalue problem yields one component of the eigenvector associated with the original eigenvalue problem. However, the other component of the eigenvector can be easily recovered in a postprocessing procedure. Therefore, the algorithms we present here are more efficient than existing algorithms that try to approximate both components of the eigenvectors simultaneously. The efficiency of the new algorithms is demonstrated by numerical examples.« less
At the Atrioventricular Crossroads: Dual Pathway Electrophysiology in the Atrioventricular Node and its Underlying Heterogeneities

PubMed Central

George, Sharon A; Faye, N Rokhaya; Murillo-Berlioz, Alejandro; Lee, K Benjamin; Trachiotis, Gregory D; Efimov, Igor R

2017-01-01

The atrioventricular node (AVN) is a complex structure that performs a variety of functions in the heart. The AVN is primarily an electrical gatekeeper between the atria and ventricles and introduces a delay between atrial and ventricular excitation, allowing for efficient ventricular filling. The AVN is composed of several compartments that safely transmit electrical excitation from the atria to the ventricles via the fast or slow pathways. There are many electrophysiological differences between these pathways, including conduction time and electrical refractoriness, that increase the predisposition of the atrioventricular junction to arrhythmias such as atrioventricular nodal re-entrant tachycardia. These varied electrophysiological characteristics of the fast and slow pathways stem from their unique structural and molecular composition (tissue and cellular geometry, ion channels and gap junctions). This review summarises the structural and molecular heterogeneities of the human AVN and how they result in electrophysiological variations and arrhythmias. PMID:29326832
An interglomerular circuit gates glomerular output and implements gain control in the mouse olfactory bulb

PubMed Central

Banerjee, Arkarup; Marbach, Fred; Anselmi, Francesca; Koh, Matthew S.; Davis, Martin B.; da Silva, Pedro Garcia; Delevich, Kristen; Oyibo, Hassana K.; Gupta, Priyanka; Li, Bo; Albeanu, Dinu F.

2015-01-01

Summary Odors elicit distributed activation of glomeruli in the olfactory bulb (OB). Crosstalk between co-active glomeruli has been proposed to perform a variety of computations, facilitating efficient extraction of sensory information by the cortex. Dopaminergic/GABAergic cells in the OB, which can be identified by their expression of the dopamine transporter (DAT), provide the earliest opportunity for such crosstalk. Here we show in mice that DAT+ cells carry concentration dependent odor signals and broadcast focal glomerular inputs throughout the OB to cause suppression of mitral/tufted (M/T) cell firing, an effect that is mediated by the external tufted (ET) cells coupled to DAT+ cells via chemical and electrical synapses. We find that DAT+ cells implement gain control and decorrelate odor representations in the M/T cell population. Our results further indicate that ET cells are gatekeepers of glomerular output and prime determinants of M/T responsiveness. PMID:26139373
AEGIS: A Lightweight Firewall for Wireless Sensor Networks

NASA Astrophysics Data System (ADS)

Hossain, Mohammad Sajjad; Raghunathan, Vijay

Firewalls are an essential component in today's networked computing systems (desktops, laptops, and servers) and provide effective protection against a variety of over-the-network security attacks. With the development of technologies such as IPv6 and 6LoWPAN that pave the way for Internet-connected embedded systems and sensor networks, these devices will soon be subject to (and need to be defended against) similar security threats. As a first step, this paper presents Aegis, a lightweight, rule-based firewall for networked embedded systems such as wireless sensor networks. Aegis is based on a semantically rich, yet simple, rule definition language. In addition, Aegis is highly efficient during operation, runs in a transparent manner from running applications, and is easy to maintain. Experimental results obtained using real sensor nodes and cycle-accurate simulations demonstrate that Aegis successfully performs gatekeeping of a sensor node's communication traffic in a flexible manner with minimal overheads.
Improved Ant Colony Clustering Algorithm and Its Performance Study

PubMed Central

Gao, Wei

2016-01-01

Clustering analysis is used in many disciplines and applications; it is an important tool that descriptively identifies homogeneous groups of objects based on attribute values. The ant colony clustering algorithm is a swarm-intelligent method used for clustering problems that is inspired by the behavior of ant colonies that cluster their corpses and sort their larvae. A new abstraction ant colony clustering algorithm using a data combination mechanism is proposed to improve the computational efficiency and accuracy of the ant colony clustering algorithm. The abstraction ant colony clustering algorithm is used to cluster benchmark problems, and its performance is compared with the ant colony clustering algorithm and other methods used in existing literature. Based on similar computational difficulties and complexities, the results show that the abstraction ant colony clustering algorithm produces results that are not only more accurate but also more efficiently determined than the ant colony clustering algorithm and the other methods. Thus, the abstraction ant colony clustering algorithm can be used for efficient multivariate data clustering. PMID:26839533
An efficient algorithm for choosing the degree of a polynomial to approximate discrete nonoscillatory data

NASA Technical Reports Server (NTRS)

Hedgley, D. R.

1978-01-01

An efficient algorithm for selecting the degree of a polynomial that defines a curve that best approximates a data set was presented. This algorithm was applied to both oscillatory and nonoscillatory data without loss of generality.
Efficient Fingercode Classification

NASA Astrophysics Data System (ADS)

Sun, Hong-Wei; Law, Kwok-Yan; Gollmann, Dieter; Chung, Siu-Leung; Li, Jian-Bin; Sun, Jia-Guang

In this paper, we present an efficient fingerprint classification algorithm which is an essential component in many critical security application systems e. g. systems in the e-government and e-finance domains. Fingerprint identification is one of the most important security requirements in homeland security systems such as personnel screening and anti-money laundering. The problem of fingerprint identification involves searching (matching) the fingerprint of a person against each of the fingerprints of all registered persons. To enhance performance and reliability, a common approach is to reduce the search space by firstly classifying the fingerprints and then performing the search in the respective class. Jain et al. proposed a fingerprint classification algorithm based on a two-stage classifier, which uses a K-nearest neighbor classifier in its first stage. The fingerprint classification algorithm is based on the fingercode representation which is an encoding of fingerprints that has been demonstrated to be an effective fingerprint biometric scheme because of its ability to capture both local and global details in a fingerprint image. We enhance this approach by improving the efficiency of the K-nearest neighbor classifier for fingercode-based fingerprint classification. Our research firstly investigates the various fast search algorithms in vector quantization (VQ) and the potential application in fingerprint classification, and then proposes two efficient algorithms based on the pyramid-based search algorithms in VQ. Experimental results on DB1 of FVC 2004 demonstrate that our algorithms can outperform the full search algorithm and the original pyramid-based search algorithms in terms of computational efficiency without sacrificing accuracy.
Two efficient label-equivalence-based connected-component labeling algorithms for 3-D binary images.

PubMed

He, Lifeng; Chao, Yuyan; Suzuki, Kenji

2011-08-01

Whenever one wants to distinguish, recognize, and/or measure objects (connected components) in binary images, labeling is required. This paper presents two efficient label-equivalence-based connected-component labeling algorithms for 3-D binary images. One is voxel based and the other is run based. For the voxel-based one, we present an efficient method of deciding the order for checking voxels in the mask. For the run-based one, instead of assigning each foreground voxel, we assign each run a provisional label. Moreover, we use run data to label foreground voxels without scanning any background voxel in the second scan. Experimental results have demonstrated that our voxel-based algorithm is efficient for 3-D binary images with complicated connected components, that our run-based one is efficient for those with simple connected components, and that both are much more efficient than conventional 3-D labeling algorithms.
Energy-Efficient Routing and Spectrum Assignment Algorithm with Physical-Layer Impairments Constraint in Flexible Optical Networks

NASA Astrophysics Data System (ADS)

Zhao, Jijun; Zhang, Nawa; Ren, Danping; Hu, Jinhua

2017-12-01

The recently proposed flexible optical network can provide more efficient accommodation of multiple data rates than the current wavelength-routed optical networks. Meanwhile, the energy efficiency has also been a hot topic because of the serious energy consumption problem. In this paper, the energy efficiency problem of flexible optical networks with physical-layer impairments constraint is studied. We propose a combined impairment-aware and energy-efficient routing and spectrum assignment (RSA) algorithm based on the link availability, in which the impact of power consumption minimization on signal quality is considered. By applying the proposed algorithm, the connection requests are established on a subset of network topology, reducing the number of transitions from sleep to active state. The simulation results demonstrate that our proposed algorithm can improve the energy efficiency and spectrum resources utilization with the acceptable blocking probability and average delay.
Score-Level Fusion of Phase-Based and Feature-Based Fingerprint Matching Algorithms

NASA Astrophysics Data System (ADS)

Ito, Koichi; Morita, Ayumi; Aoki, Takafumi; Nakajima, Hiroshi; Kobayashi, Koji; Higuchi, Tatsuo

This paper proposes an efficient fingerprint recognition algorithm combining phase-based image matching and feature-based matching. In our previous work, we have already proposed an efficient fingerprint recognition algorithm using Phase-Only Correlation (POC), and developed commercial fingerprint verification units for access control applications. The use of Fourier phase information of fingerprint images makes it possible to achieve robust recognition for weakly impressed, low-quality fingerprint images. This paper presents an idea of improving the performance of POC-based fingerprint matching by combining it with feature-based matching, where feature-based matching is introduced in order to improve recognition efficiency for images with nonlinear distortion. Experimental evaluation using two different types of fingerprint image databases demonstrates efficient recognition performance of the combination of the POC-based algorithm and the feature-based algorithm.
A robust embedded vision system feasible white balance algorithm

NASA Astrophysics Data System (ADS)

Wang, Yuan; Yu, Feihong

2018-01-01

White balance is a very important part of the color image processing pipeline. In order to meet the need of efficiency and accuracy in embedded machine vision processing system, an efficient and robust white balance algorithm combining several classical ones is proposed. The proposed algorithm mainly has three parts. Firstly, in order to guarantee higher efficiency, an initial parameter calculated from the statistics of R, G and B components from raw data is used to initialize the following iterative method. After that, the bilinear interpolation algorithm is utilized to implement demosaicing procedure. Finally, an adaptive step adjustable scheme is introduced to ensure the controllability and robustness of the algorithm. In order to verify the proposed algorithm's performance on embedded vision system, a smart camera based on IMX6 DualLite, IMX291 and XC6130 is designed. Extensive experiments on a large amount of images under different color temperatures and exposure conditions illustrate that the proposed white balance algorithm avoids color deviation problem effectively, achieves a good balance between efficiency and quality, and is suitable for embedded machine vision processing system.
Mining algorithm for association rules in big data based on Hadoop

NASA Astrophysics Data System (ADS)

Fu, Chunhua; Wang, Xiaojing; Zhang, Lijun; Qiao, Liying

2018-04-01

In order to solve the problem that the traditional association rules mining algorithm has been unable to meet the mining needs of large amount of data in the aspect of efficiency and scalability, take FP-Growth as an example, the algorithm is realized in the parallelization based on Hadoop framework and Map Reduce model. On the basis, it is improved using the transaction reduce method for further enhancement of the algorithm's mining efficiency. The experiment, which consists of verification of parallel mining results, comparison on efficiency between serials and parallel, variable relationship between mining time and node number and between mining time and data amount, is carried out in the mining results and efficiency by Hadoop clustering. Experiments show that the paralleled FP-Growth algorithm implemented is able to accurately mine frequent item sets, with a better performance and scalability. It can be better to meet the requirements of big data mining and efficiently mine frequent item sets and association rules from large dataset.
Research on personalized recommendation algorithm based on spark

NASA Astrophysics Data System (ADS)

Li, Zeng; Liu, Yu

2018-04-01

With the increasing amount of data in the past years, the traditional recommendation algorithm has been unable to meet people's needs. Therefore, how to better recommend their products to users of interest, become the opportunities and challenges of the era of big data development. At present, each platform enterprise has its own recommendation algorithm, but how to make efficient and accurate push information is still an urgent problem for personalized recommendation system. In this paper, a hybrid algorithm based on user collaborative filtering and content-based recommendation algorithm is proposed on Spark to improve the efficiency and accuracy of recommendation by weighted processing. The experiment shows that the recommendation under this scheme is more efficient and accurate.
The new and computationally efficient MIL-SOM algorithm: potential benefits for visualization and analysis of a large-scale high-dimensional clinically acquired geographic data.

PubMed

Oyana, Tonny J; Achenie, Luke E K; Heo, Joon

2012-01-01

The objective of this paper is to introduce an efficient algorithm, namely, the mathematically improved learning-self organizing map (MIL-SOM) algorithm, which speeds up the self-organizing map (SOM) training process. In the proposed MIL-SOM algorithm, the weights of Kohonen's SOM are based on the proportional-integral-derivative (PID) controller. Thus, in a typical SOM learning setting, this improvement translates to faster convergence. The basic idea is primarily motivated by the urgent need to develop algorithms with the competence to converge faster and more efficiently than conventional techniques. The MIL-SOM algorithm is tested on four training geographic datasets representing biomedical and disease informatics application domains. Experimental results show that the MIL-SOM algorithm provides a competitive, better updating procedure and performance, good robustness, and it runs faster than Kohonen's SOM.
The New and Computationally Efficient MIL-SOM Algorithm: Potential Benefits for Visualization and Analysis of a Large-Scale High-Dimensional Clinically Acquired Geographic Data

PubMed Central

Oyana, Tonny J.; Achenie, Luke E. K.; Heo, Joon

2012-01-01

The objective of this paper is to introduce an efficient algorithm, namely, the mathematically improved learning-self organizing map (MIL-SOM) algorithm, which speeds up the self-organizing map (SOM) training process. In the proposed MIL-SOM algorithm, the weights of Kohonen's SOM are based on the proportional-integral-derivative (PID) controller. Thus, in a typical SOM learning setting, this improvement translates to faster convergence. The basic idea is primarily motivated by the urgent need to develop algorithms with the competence to converge faster and more efficiently than conventional techniques. The MIL-SOM algorithm is tested on four training geographic datasets representing biomedical and disease informatics application domains. Experimental results show that the MIL-SOM algorithm provides a competitive, better updating procedure and performance, good robustness, and it runs faster than Kohonen's SOM. PMID:22481977
Solving SAT Problem Based on Hybrid Differential Evolution Algorithm

NASA Astrophysics Data System (ADS)

Liu, Kunqi; Zhang, Jingmin; Liu, Gang; Kang, Lishan

Satisfiability (SAT) problem is an NP-complete problem. Based on the analysis about it, SAT problem is translated equally into an optimization problem on the minimum of objective function. A hybrid differential evolution algorithm is proposed to solve the Satisfiability problem. It makes full use of strong local search capacity of hill-climbing algorithm and strong global search capability of differential evolution algorithm, which makes up their disadvantages, improves the efficiency of algorithm and avoids the stagnation phenomenon. The experiment results show that the hybrid algorithm is efficient in solving SAT problem.
An Adaptive Evolutionary Algorithm for Traveling Salesman Problem with Precedence Constraints

PubMed Central

Sung, Jinmo; Jeong, Bongju

2014-01-01

Traveling sales man problem with precedence constraints is one of the most notorious problems in terms of the efficiency of its solution approach, even though it has very wide range of industrial applications. We propose a new evolutionary algorithm to efficiently obtain good solutions by improving the search process. Our genetic operators guarantee the feasibility of solutions over the generations of population, which significantly improves the computational efficiency even when it is combined with our flexible adaptive searching strategy. The efficiency of the algorithm is investigated by computational experiments. PMID:24701158
An adaptive evolutionary algorithm for traveling salesman problem with precedence constraints.

PubMed

Sung, Jinmo; Jeong, Bongju

2014-01-01

Traveling sales man problem with precedence constraints is one of the most notorious problems in terms of the efficiency of its solution approach, even though it has very wide range of industrial applications. We propose a new evolutionary algorithm to efficiently obtain good solutions by improving the search process. Our genetic operators guarantee the feasibility of solutions over the generations of population, which significantly improves the computational efficiency even when it is combined with our flexible adaptive searching strategy. The efficiency of the algorithm is investigated by computational experiments.

Scaling-up strategic purchasing: analysis of health system governance imperatives for strategic purchasing in a free maternal and child healthcare programme in Enugu State, Nigeria.

PubMed

Ogbuabor, Daniel Chukwuemeka; Onwujekwe, Obinna Emmanuel

2018-04-05

Significant knowledge gaps exist in the functioning of institutional designs and organisational practices in purchasing within free healthcare schemes in low resource countries. The study provides evidence of the governance requirements to scale up strategic purchasing in free healthcare policies in Nigeria and other low-resource settings facing similar approaches. The study was conducted at the Ministry of Health and in two health districts in Enugu State, Nigeria, using a qualitative case study design. Semi-structured interviews were conducted with 44 key health system actors (16 policymakers, 16 providers and 12 health facility committee leaders) purposively selected from the Ministry of Health and the two health districts. Data collection and analysis were guided by Siddiqi and colleagues' health system governance framework. Data were analysed using a framework approach. The key findings show that supportive governance practices in purchasing included systems to verify questionable provider claims, pay providers directly for services, compel providers to procure drugs centrally and track transfer of funds to providers. However, strategic vision was undermined by institutional conflicts, absence of purchaser-provider split and lack of selective contracting of providers. Benefit design was not based on stakeholder involvement. Rule of law was limited by delays in provider payment. Benefits and obligations to users were not transparent. The criteria and procedure for resource allocation were unclear. Some target beneficiaries seemed excluded from the scheme. Effectiveness and efficiency was constrained by poor adherence to purchasing rules. Accountability of purchasers and providers to users was weak. Intelligence and information is constrained by paper-based system. Rationing of free services by providers and users' non-adherence to primary gate-keeping role hindered ethics. Weak governance of purchasing function limits potential of FMCHP to contribute towards universal health coverage. Appropriate governance model for strengthening strategic purchasing in the FMCHP and possibly free healthcare interventions in other low-resource countries must pay attention to the creation of an autonomous purchasing agency, clear framework for selective contracting, stakeholder involvement, transparent benefit design, need-based resource allocation, efficient provider payment methods, stronger roles for citizens, enforcement of gatekeeping rules and use of data for decision-making.
An efficient and accurate 3D displacements tracking strategy for digital volume correlation

NASA Astrophysics Data System (ADS)

Pan, Bing; Wang, Bo; Wu, Dafang; Lubineau, Gilles

2014-07-01

Owing to its inherent computational complexity, practical implementation of digital volume correlation (DVC) for internal displacement and strain mapping faces important challenges in improving its computational efficiency. In this work, an efficient and accurate 3D displacement tracking strategy is proposed for fast DVC calculation. The efficiency advantage is achieved by using three improvements. First, to eliminate the need of updating Hessian matrix in each iteration, an efficient 3D inverse compositional Gauss-Newton (3D IC-GN) algorithm is introduced to replace existing forward additive algorithms for accurate sub-voxel displacement registration. Second, to ensure the 3D IC-GN algorithm that converges accurately and rapidly and avoid time-consuming integer-voxel displacement searching, a generalized reliability-guided displacement tracking strategy is designed to transfer accurate and complete initial guess of deformation for each calculation point from its computed neighbors. Third, to avoid the repeated computation of sub-voxel intensity interpolation coefficients, an interpolation coefficient lookup table is established for tricubic interpolation. The computational complexity of the proposed fast DVC and the existing typical DVC algorithms are first analyzed quantitatively according to necessary arithmetic operations. Then, numerical tests are performed to verify the performance of the fast DVC algorithm in terms of measurement accuracy and computational efficiency. The experimental results indicate that, compared with the existing DVC algorithm, the presented fast DVC algorithm produces similar precision and slightly higher accuracy at a substantially reduced computational cost.
T-L Plane Abstraction-Based Energy-Efficient Real-Time Scheduling for Multi-Core Wireless Sensors.

PubMed

Kim, Youngmin; Lee, Ki-Seong; Pham, Ngoc-Son; Lee, Sun-Ro; Lee, Chan-Gun

2016-07-08

Energy efficiency is considered as a critical requirement for wireless sensor networks. As more wireless sensor nodes are equipped with multi-cores, there are emerging needs for energy-efficient real-time scheduling algorithms. The T-L plane-based scheme is known to be an optimal global scheduling technique for periodic real-time tasks on multi-cores. Unfortunately, there has been a scarcity of studies on extending T-L plane-based scheduling algorithms to exploit energy-saving techniques. In this paper, we propose a new T-L plane-based algorithm enabling energy-efficient real-time scheduling on multi-core sensor nodes with dynamic power management (DPM). Our approach addresses the overhead of processor mode transitions and reduces fragmentations of the idle time, which are inherent in T-L plane-based algorithms. Our experimental results show the effectiveness of the proposed algorithm compared to other energy-aware scheduling methods on T-L plane abstraction.
Paradigms, Exemplars and Social Change

ERIC Educational Resources Information Center

Lawson, Hal A.

2009-01-01

Researchers' social-cultural organization influences the scope, quality, quantity, coherence, dissemination, utilization and impact of research-based, theoretically sound knowledge. Five concepts--paradigm, exemplar, segment, network and gatekeeper--are salient to research on researchers' organization. Autobiographical reflections signal these…
Bioethics and its gatekeepers: does institutional racism exist in leading bioethics journals?

PubMed

Chattopadhyay, Subrata; Myser, Catherine; De Vries, Raymond

2013-03-01

Who are the gatekeepers in bioethics? Does editorial bias or institutional racism exist in leading bioethics journals? We analyzed the composition of the editorial boards of 14 leading bioethics journals by country. Categorizing these countries according to their Human Development Index (HDI), we discovered that approximately 95 percent of editorial board members are based in (very) high-HDI countries, less than 4 percent are from medium-HDI countries, and fewer than 1.5 percent are from low-HDI countries. Eight out of 14 leading bioethics journals have no editorial board members from a medium- or low-HDI country. Eleven bioethics journals have no board members from low-HDI countries. This severe underrepresentation of bioethics scholars from developing countries on editorial boards suggests that bioethics may be affected by institutional racism, raising significant questions about the ethics of bioethics in a global context.
Engaging Gatekeepers, Optimizing Decision Making, and Mitigating Bias: Design Specifications for Systemic Diversity Interventions.

PubMed

Vinkenburg, Claartje J

2017-06-01

In this contribution to the Journal of Applied Behavioral Science Special Issue on Understanding Diversity Dynamics in Systems: Social Equality as an Organization Change Issue, I develop and describe design specifications for systemic diversity interventions in upward mobility career systems, aimed at optimizing decision making through mitigating bias by engaging gatekeepers. These interventions address the paradox of meritocracy that underlies the surprising lack of diversity at the top of the career pyramid in these systems. I ground the design specifications in the limited empirical evidence on "what works" in systemic interventions. Specifically, I describe examples from interventions in academic settings, including a bias literacy program, participatory modeling, and participant observation. The design specifications, paired with inspirational examples of successful interventions, should assist diversity officers and consultants in designing and implementing interventions to promote the advancement to and representation of nondominant group members at the top of the organizational hierarchy.
Engaging Gatekeepers, Optimizing Decision Making, and Mitigating Bias: Design Specifications for Systemic Diversity Interventions

PubMed Central

Vinkenburg, Claartje J.

2017-01-01

In this contribution to the Journal of Applied Behavioral Science Special Issue on Understanding Diversity Dynamics in Systems: Social Equality as an Organization Change Issue, I develop and describe design specifications for systemic diversity interventions in upward mobility career systems, aimed at optimizing decision making through mitigating bias by engaging gatekeepers. These interventions address the paradox of meritocracy that underlies the surprising lack of diversity at the top of the career pyramid in these systems. I ground the design specifications in the limited empirical evidence on “what works” in systemic interventions. Specifically, I describe examples from interventions in academic settings, including a bias literacy program, participatory modeling, and participant observation. The design specifications, paired with inspirational examples of successful interventions, should assist diversity officers and consultants in designing and implementing interventions to promote the advancement to and representation of nondominant group members at the top of the organizational hierarchy. PMID:28546644
Noninvasive remote-controlled release of drug molecules in vitro using magnetic actuation of mechanized nanoparticles.

PubMed

Thomas, Courtney R; Ferris, Daniel P; Lee, Jae-Hyun; Choi, Eunjoo; Cho, Mi Hyeon; Kim, Eun Sook; Stoddart, J Fraser; Shin, Jeon-Soo; Cheon, Jinwoo; Zink, Jeffrey I

2010-08-11

Mesoporous silica nanoparticles are useful nanomaterials that have demonstrated the ability to contain and release cargos with mediation by gatekeepers. Magnetic nanocrystals have the ability to exhibit hyperthermic effects when placed in an oscillating magnetic field. In a system combining these two materials and a thermally sensitive gatekeeper, a unique drug delivery system can be produced. A novel material that incorporates zinc-doped iron oxide nanocrystals within a mesoporous silica framework that has been surface-modified with pseudorotaxanes is described. Upon application of an AC magnetic field, the nanocrystals generate local internal heating, causing the molecular machines to disassemble and allowing the cargos (drugs) to be released. When breast cancer cells (MDA-MB-231) were treated with doxorubicin-loaded particles and exposed to an AC field, cell death occurred. This material promises to be a noninvasive, externally controlled drug delivery system with cancer-killing properties.
Body integrity identity disorder beyond amputation: consent and liberty.

PubMed

White, Amy

2014-09-01

In this article, I argue that persons suffering from Body Integrity Identity Disorder (BIID) can give informed consent to surgical measures designed to treat this disorder. This is true even if the surgery seems radical or irrational to most people. The decision to have surgery made by a BIID patient is not necessarily coerced, incompetent or uninformed. If surgery for BIID is offered, there should certainly be a screening process in place to insure informed consent. It is beyond the scope of this work, however, to define all the conditions that should be placed on the availability of surgery. However, I argue, given the similarities between BIID and gender dysphoria and the success of such gatekeeping measures for the surgical treatment of gender dysphoria, it is reasonable that similar conditions be in place for BIID. Once other treatment options are tried and gatekeeping measures satisfied, A BIID patient can give informed consent to radical surgery.
Application of composite dictionary multi-atom matching in gear fault diagnosis.

PubMed

Cui, Lingli; Kang, Chenhui; Wang, Huaqing; Chen, Peng

2011-01-01

The sparse decomposition based on matching pursuit is an adaptive sparse expression method for signals. This paper proposes an idea concerning a composite dictionary multi-atom matching decomposition and reconstruction algorithm, and the introduction of threshold de-noising in the reconstruction algorithm. Based on the structural characteristics of gear fault signals, a composite dictionary combining the impulse time-frequency dictionary and the Fourier dictionary was constituted, and a genetic algorithm was applied to search for the best matching atom. The analysis results of gear fault simulation signals indicated the effectiveness of the hard threshold, and the impulse or harmonic characteristic components could be separately extracted. Meanwhile, the robustness of the composite dictionary multi-atom matching algorithm at different noise levels was investigated. Aiming at the effects of data lengths on the calculation efficiency of the algorithm, an improved segmented decomposition and reconstruction algorithm was proposed, and the calculation efficiency of the decomposition algorithm was significantly enhanced. In addition it is shown that the multi-atom matching algorithm was superior to the single-atom matching algorithm in both calculation efficiency and algorithm robustness. Finally, the above algorithm was applied to gear fault engineering signals, and achieved good results.
A High Fuel Consumption Efficiency Management Scheme for PHEVs Using an Adaptive Genetic Algorithm

PubMed Central

Lee, Wah Ching; Tsang, Kim Fung; Chi, Hao Ran; Hung, Faan Hei; Wu, Chung Kit; Chui, Kwok Tai; Lau, Wing Hong; Leung, Yat Wah

2015-01-01

A high fuel efficiency management scheme for plug-in hybrid electric vehicles (PHEVs) has been developed. In order to achieve fuel consumption reduction, an adaptive genetic algorithm scheme has been designed to adaptively manage the energy resource usage. The objective function of the genetic algorithm is implemented by designing a fuzzy logic controller which closely monitors and resembles the driving conditions and environment of PHEVs, thus trading off between petrol versus electricity for optimal driving efficiency. Comparison between calculated results and publicized data shows that the achieved efficiency of the fuzzified genetic algorithm is better by 10% than existing schemes. The developed scheme, if fully adopted, would help reduce over 600 tons of CO2 emissions worldwide every day. PMID:25587974
Changing choices in health care: implications for equity, efficiency and cost.

PubMed

Bevan, Gwyn; Helderman, Jan-Kees; Wilsford, David

2010-07-01

Although choice may be seen as an end in itself, the papers included in this special issue of Health Economics, Policy and Law, examine choice policies in European systems of health care, which aim to be effective instruments for ameliorating the systemic pressures from the iron triangle of equity, efficiency, and cost. Three papers consider the nature of differences between and within countries following the Beveridge and Bismarck models of financing and organising the delivery of care, and how choices are changing within different systems. Within countries following the Beveridge model, current policies in England, Denmark and Sweden emphasise increasing patient choice of provider. Within countries following the Bismarck model, current policies in France and Germany seek to restrict choice of specialists by introducing 'soft' gatekeeping; and in the Netherlands there is a system of managed competition with choice of insurer that, in principle, allows insurers to contract selectively with providers. A fourth paper considers how government policies that seek to restrict choice within systems of universal coverage have been subject to challenges in the courts. A commentary explores the implications of the fraught and complex nature of choices between insurers and providers of health care for designing effective choice policies.
The mitochondrial pyruvate carrier in health and disease: To carry or not to carry?

PubMed

Bender, Tom; Martinou, Jean-Claude

2016-10-01

Mitochondria play a key role in energy metabolism, hosting the machinery for oxidative phosphorylation, the most efficient cellular pathway for generating ATP. A major checkpoint in this process is the transport of pyruvate produced by cytosolic glycolysis into the mitochondrial matrix, which is accomplished by the recently identified mitochondrial pyruvate carrier (MPC). As the gatekeeper for pyruvate entry into mitochondria, the MPC is thought to be of fundamental importance in establishing the metabolic programming of a cell. This is especially relevant in the context of the aerobic glycolysis, also known as the Warburg effect, which is a hallmark in many types of cancer, and MPC loss of function promotes cancer growth. Moreover, mitochondrial pyruvate uptake is needed for efficient hepatic gluconeogenesis and the regulation of blood glucose levels. In this review we discuss recent advances in our knowledge of the MPC, and we argue that it may offer a promising target in diseases like cancer and type 2 diabetes. This article is part of a Special Issue entitled: Mitochondrial Channels edited by Pierre Sonveaux, Pierre Maechler and Jean-Claude Martinou. Copyright © 2016 Elsevier B.V. All rights reserved.
An Improved Perturb and Observe Algorithm for Photovoltaic Motion Carriers

NASA Astrophysics Data System (ADS)

Peng, Lele; Xu, Wei; Li, Liming; Zheng, Shubin

2018-03-01

An improved perturbation and observation algorithm for photovoltaic motion carriers is proposed in this paper. The model of the proposed algorithm is given by using Lambert W function and tangent error method. Moreover, by using matlab and experiment of photovoltaic system, the tracking performance of the proposed algorithm is tested. And the results demonstrate that the improved algorithm has fast tracking speed and high efficiency. Furthermore, the energy conversion efficiency by the improved method has increased by nearly 8.2%.
Fast Steerable Principal Component Analysis

PubMed Central

Zhao, Zhizhen; Shkolnisky, Yoel; Singer, Amit

2016-01-01

Cryo-electron microscopy nowadays often requires the analysis of hundreds of thousands of 2-D images as large as a few hundred pixels in each direction. Here, we introduce an algorithm that efficiently and accurately performs principal component analysis (PCA) for a large set of 2-D images, and, for each image, the set of its uniform rotations in the plane and their reflections. For a dataset consisting of n images of size L × L pixels, the computational complexity of our algorithm is O(nL3 + L4), while existing algorithms take O(nL4). The new algorithm computes the expansion coefficients of the images in a Fourier–Bessel basis efficiently using the nonuniform fast Fourier transform. We compare the accuracy and efficiency of the new algorithm with traditional PCA and existing algorithms for steerable PCA. PMID:27570801
Diffeomorphic demons: efficient non-parametric image registration.

PubMed

Vercauteren, Tom; Pennec, Xavier; Perchant, Aymeric; Ayache, Nicholas

2009-03-01

We propose an efficient non-parametric diffeomorphic image registration algorithm based on Thirion's demons algorithm. In the first part of this paper, we show that Thirion's demons algorithm can be seen as an optimization procedure on the entire space of displacement fields. We provide strong theoretical roots to the different variants of Thirion's demons algorithm. This analysis predicts a theoretical advantage for the symmetric forces variant of the demons algorithm. We show on controlled experiments that this advantage is confirmed in practice and yields a faster convergence. In the second part of this paper, we adapt the optimization procedure underlying the demons algorithm to a space of diffeomorphic transformations. In contrast to many diffeomorphic registration algorithms, our solution is computationally efficient since in practice it only replaces an addition of displacement fields by a few compositions. Our experiments show that in addition to being diffeomorphic, our algorithm provides results that are similar to the ones from the demons algorithm but with transformations that are much smoother and closer to the gold standard, available in controlled experiments, in terms of Jacobians.
SA-SOM algorithm for detecting communities in complex networks

NASA Astrophysics Data System (ADS)

Chen, Luogeng; Wang, Yanran; Huang, Xiaoming; Hu, Mengyu; Hu, Fang

2017-10-01

Currently, community detection is a hot topic. This paper, based on the self-organizing map (SOM) algorithm, introduced the idea of self-adaptation (SA) that the number of communities can be identified automatically, a novel algorithm SA-SOM of detecting communities in complex networks is proposed. Several representative real-world networks and a set of computer-generated networks by LFR-benchmark are utilized to verify the accuracy and the efficiency of this algorithm. The experimental findings demonstrate that this algorithm can identify the communities automatically, accurately and efficiently. Furthermore, this algorithm can also acquire higher values of modularity, NMI and density than the SOM algorithm does.
Gatekeepers' perceptions of the quality and availability of services for breast and cervical cancer patients in the English-speaking Windward Islands: an exploratory investigation.

PubMed

Thomas-Purcell, Kamilah B; Tarver, Will L; Richards, Christine; Primus-Joseph, Marva

2017-11-01

Although extensive screening services for breast and cervical cancers are available in the Caribbean, these cancers continue to be the leading causes of cancer death among women in this region. The purpose of this study was to determine the quality and availability of breast and cervical cancer treatment care and support services from the perspective of the gatekeepers who provide care for the patients in the Windward Islands of Dominica, Grenada, St Lucia, and St. Vincent. A qualitative research design using semi-structured, in-depth interviews was used to gather data from gatekeepers who provided oncology prevention and care services to patients for at least one year. Data were collected on availability and quality of cancer care and treatment services and coded using the themes obtained via thematic analysis of the data. Twenty-three current providers participated in the study (Dominica, 5; Grenada, 7; St. Lucia, 5; St. Vincent and the Grenadines, 6). The participants' years of work experience ranged from 2 to 45 years. The codes encompassed a range of social ecological factors that influence breast and cervical cancer screening and treatment in the Windward Islands. The emergent themes were availability of resources, cost of care, and social support. The findings of this study emphasize the varying social determinants of health that affect breast and cervical cancer prevention and treatment. It also highlights the disparities in availability of treatment within the wider Caribbean. It is necessary to broaden the perspective on health from a purely biomedical paradigm to a social perspective.
Is the role as gatekeeper still feasible? A survey among Dutch general practitioners.

PubMed

Wammes, Joost Johan Godert; Jeurissen, Patrick Paulus Theodoor; Verhoef, Lise Maria; Assendelft, Willem J J; Westert, Gert P; Faber, Marjan J

2014-10-01

In the 2012 International Health Policy Survey by the Commonwealth Fund, 57% of Dutch GPs indicated that Dutch patients receive too much health care. This is an unexpected finding, given the clear gatekeeper role of Dutch GPs and recent efforts strengthening this role. The study aims to explore where perceived overuse of care prevails and to identify factors associated with too much care at the entry point of Dutch health care. An American survey exploring perceptions of the amount of care among primary care providers was modified for relevance to the Dutch health system. We further included additional factors possibly related to overuse based on 12 interviews with Dutch GPs. The survey was sent to a random sample of 600 GPs. Dutch GPs (N = 157; response rate 26.2%) indicated that patients receive (much) too much care in general hospitals, primary care, GP cooperatives as well as private clinics. The Dutch responding GPs showed a relatively demand-satisfying attitude, which contributed to the delivery of too much care, often leading to deviation from guidelines and professional norms. The increasing availability of diagnostic facilities was identified as an additional factor contributing to the provision of unnecessary care. Finally, funding gaps between primary care and hospitals impede cooperation and coordination, provoking unnecessary care. Our results--most notably regarding the demand-satisfying attitude of responding GPs--call into question the classical view of the guidance and gatekeeper role of GPs in the Dutch health care system. © The Author 2014. Published by Oxford University Press. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.
Parallel AFSA algorithm accelerating based on MIC architecture

NASA Astrophysics Data System (ADS)

Zhou, Junhao; Xiao, Hong; Huang, Yifan; Li, Yongzhao; Xu, Yuanrui

2017-05-01

Analysis AFSA past for solving the traveling salesman problem, the algorithm efficiency is often a big problem, and the algorithm processing method, it does not fully responsive to the characteristics of the traveling salesman problem to deal with, and therefore proposes a parallel join improved AFSA process. The simulation with the current TSP known optimal solutions were analyzed, the results showed that the AFSA iterations improved less, on the MIC cards doubled operating efficiency, efficiency significantly.

A class of parallel algorithms for computation of the manipulator inertia matrix

NASA Technical Reports Server (NTRS)

Fijany, Amir; Bejczy, Antal K.

1989-01-01

Parallel and parallel/pipeline algorithms for computation of the manipulator inertia matrix are presented. An algorithm based on composite rigid-body spatial inertia method, which provides better features for parallelization, is used for the computation of the inertia matrix. Two parallel algorithms are developed which achieve the time lower bound in computation. Also described is the mapping of these algorithms with topological variation on a two-dimensional processor array, with nearest-neighbor connection, and with cardinality variation on a linear processor array. An efficient parallel/pipeline algorithm for the linear array was also developed, but at significantly higher efficiency.
Diffusion of Educational Knowledge Through Journals: Gatekeepers' Selection Criteria

ERIC Educational Resources Information Center

Silverman, Robert J.

1978-01-01

Report is made of a survey of 248 editors representing scholarly, professional, association, and research journals in regard to their editorial role, criteria for accepting or rejecting manuscripts, and selection of editorial boards and reviewers. (Author/MJB)
Connecting with the CEO.

ERIC Educational Resources Information Center

Dolbert, Susan Clouse

2002-01-01

Describes the roles played by college presidents in alumni relations, including campus beacon, institution tactician, alumni relations advocate, and campus connector. Discusses the responsibilities of alumni relations executives toward college presidents, including as a channel to alumni, presidential gatekeeper, and "outsider." Includes…
How the probability of presentation to a primary care clinician correlates with cancer survival rates: a European survey using vignettes.

PubMed

Harris, Michael; Frey, Peter; Esteva, Magdalena; Gašparović Babić, Svjetlana; Marzo-Castillejo, Mercè; Petek, Davorina; Petek Ster, Marija; Thulesius, Hans

2017-03-01

European cancer survival rates vary widely. System factors, including whether or not primary care physicians (PCPs) are gatekeepers, may account for some of these differences. This study explores where patients who may have cancer are likely to present for medical care in different European countries, and how probability of presentation to a primary care clinician correlates with cancer survival rates. Seventy-eight PCPs in a range of European countries assessed four vignettes representing patients who might have cancer, and consensus groups agreed how likely those patients were to present to different clinicians in their own countries. These data were compared with national cancer survival rates. A total of 14 countries. Consensus groups of PCPs. Probability of initial presentation to a PCP for four clinical vignettes. There was no significant correlation between overall national 1-year relative cancer survival rates and the probability of initial presentation to a PCP (r = -0.16, 95% CI -0.39 to 0.08). Within that there was large variation depending on the type of cancer, with a significantly poorer lung cancer survival in countries where patients were more likely to initially consult a PCP (lung r = -0.57, 95% CI -0.83 to -0.12; ovary: r = -0.13, 95% CI -0.57 to 0.38; breast r = 0.14, 95% CI -0.36 to 0.58; bowel: r = 0.20, 95% CI -0.31 to 0.62). There were wide variations in the degree of gatekeeping between countries, with no simple binary model as to whether or not a country has a "PCP-as-gatekeeper" system. While there was case-by-case variation, there was no overall evidence of a link between a higher probability of initial consultation with a PCP and poorer cancer survival. KEY POINTS European cancer survival rates vary widely, and health system factors may account for some of these differences. The data from 14 European countries show a wide variation in the probability of initial presentation to a PCP. The degree to which PCPs act as gatekeepers varies considerably from country to country. There is no overall evidence of a link between a higher probability of initial presentation to a PCP and poorer cancer survival.
Engaging Gatekeeper-Stakeholders in Development of a Mobile Health Intervention to Improve Medication Adherence Among African American and Pacific Islander Elderly Patients With Hypertension

PubMed Central

Bazargan, Mohsen; Jones, Loretta; Vawer, May; Seto, Todd B; Farooq, Summer; Taira, Deborah A

2016-01-01

Background Approximately 70 million people in the United States have hypertension. Although antihypertensive therapy can reduce the morbidity and mortality associated with hypertension, often patients do not take their medication as prescribed. Objective The goal of this study was to better understand issues affecting the acceptability and usability of mobile health technology (mHealth) to improve medication adherence for elderly African American and Native Hawaiian and Pacific Islander patients with hypertension. Methods In-depth interviews were conducted with 20 gatekeeper-stakeholders using targeted open-ended questions. Interviews were deidentified, transcribed, organized, and coded manually by two independent coders. Analysis of patient interviews used largely a deductive approach because the targeted open-ended interview questions were designed to explore issues specific to the design and acceptability of a mHealth intervention for seniors. Results A number of similar themes regarding elements of a successful intervention emerged from our two groups of African American and Native Hawaiian and Pacific Islander gatekeeper-stakeholders. First was the need to teach participants both about the importance of adherence to antihypertensive medications. Second, was the use of mobile phones for messaging and patients need to be able to access ongoing technical support. Third, messaging needs to be short and simple, but personalized, and to come from someone the participant trusts and with whom they have a connection. There were some differences between groups. For instance, there was a strong sentiment among the African American group that the church be involved and that the intervention begin with group workshops, whereas the Native Hawaiian and Pacific Islander group seemed to believe that the teaching could occur on a one-to-one basis with the health care provider. Conclusions Information from our gatekeeper-stakeholder (key informant) interviews suggests that the design of a mHealth intervention to improve adherence to antihypertensives among the elderly could be very similar for African Americans and Native Hawaiian and Pacific Islanders. The main difference might be in the way in which the program is initiated (possibly through church-based workshops for African Americans and by individual providers for Native Hawaiian and Pacific Islanders). Another difference might be who sends the messages with African Americans wanting someone outside the health care system, but Native Hawaiian and Pacific Islanders preferring a provider. PMID:27784651
[After the Great East Japan Earthquake : suicide prevention and a gatekeeper program].

PubMed

Otsuka, Kotaro; Sakai, Akio; Nakamura, Hikaru; Akahira, Mitsuko

2014-01-01

When considering approaches to mental health in areas affected by the 2011 Great East Japan Earthquake, as well as the resulting tsunami and Fukushima nuclear power plant accident, it is not sufficient to focus interventions solely on individuals experiencing mental health issues. The situation demands a comprehensive approach that includes programs that target improvements to mental health literacy among residents in areas affected by the disaster, the rebuilding of relationships between residents themselves, collaboration with recovery and support activities, and mental health support for people participating in recovery and support efforts. From a medium- to long-term perspective, suicide prevention is an important issue. Comprehensive suicide prevention efforts are being promoted in areas of Iwate Prefecture affected by the disaster. In suicide prevention programs, it is crucial to foster the development of human resources in the local community. In order to expand community supports, it is necessary to provide education on ways of supporting those affected by a disaster to local medical personnel, people staffing inquiry and consultation offices, and people in fields related to mental health. Suicide prevention and disaster relief efforts are both approaches that target people in difficulty, and they share commonalities in principles, systems, and approaches to human resource development. "Mental health first aid" is a program developed in Australia that defines methods of early intervention by non-professionals who encounter someone experiencing a mental health problem. The mental health first aid-based gatekeeper training program of the Japanese government's Cabinet Office, which the author's research team helped to develop, allows participants to obtain the knowledge and skills required of gatekeepers. In 2012, a module for disaster-affected areas was developed and added to the program, with additional content that provides program participants with the skills to respond in crisis situations encountered during advice/counseling work in evacuation centers and temporary housing facilities. In addition, since 2011 the Cabinet Office has offered a facilitator training program that was developed based on the gatekeeper training program. Program text materials may be downloaded from the Web site of the Cabinet Office, and it is hoped that they will be used in the education of those involved in caring for people affected by a disaster.
Column generation algorithms for virtual network embedding in flexi-grid optical networks.

PubMed

Lin, Rongping; Luo, Shan; Zhou, Jingwei; Wang, Sheng; Chen, Bin; Zhang, Xiaoning; Cai, Anliang; Zhong, Wen-De; Zukerman, Moshe

2018-04-16

Network virtualization provides means for efficient management of network resources by embedding multiple virtual networks (VNs) to share efficiently the same substrate network. Such virtual network embedding (VNE) gives rise to a challenging problem of how to optimize resource allocation to VNs and to guarantee their performance requirements. In this paper, we provide VNE algorithms for efficient management of flexi-grid optical networks. We provide an exact algorithm aiming to minimize the total embedding cost in terms of spectrum cost and computation cost for a single VN request. Then, to achieve scalability, we also develop a heuristic algorithm for the same problem. We apply these two algorithms for a dynamic traffic scenario where many VN requests arrive one-by-one. We first demonstrate by simulations for the case of a six-node network that the heuristic algorithm obtains very close blocking probabilities to exact algorithm (about 0.2% higher). Then, for a network of realistic size (namely, USnet) we demonstrate that the blocking probability of our new heuristic algorithm is about one magnitude lower than a simpler heuristic algorithm, which was a component of an earlier published algorithm.
An Efficient Next Hop Selection Algorithm for Multi-Hop Body Area Networks

PubMed Central

Ayatollahitafti, Vahid; Ngadi, Md Asri; Mohamad Sharif, Johan bin; Abdullahi, Mohammed

2016-01-01

Body Area Networks (BANs) consist of various sensors which gather patient’s vital signs and deliver them to doctors. One of the most significant challenges faced, is the design of an energy-efficient next hop selection algorithm to satisfy Quality of Service (QoS) requirements for different healthcare applications. In this paper, a novel efficient next hop selection algorithm is proposed in multi-hop BANs. This algorithm uses the minimum hop count and a link cost function jointly in each node to choose the best next hop node. The link cost function includes the residual energy, free buffer size, and the link reliability of the neighboring nodes, which is used to balance the energy consumption and to satisfy QoS requirements in terms of end to end delay and reliability. Extensive simulation experiments were performed to evaluate the efficiency of the proposed algorithm using the NS-2 simulator. Simulation results show that our proposed algorithm provides significant improvement in terms of energy consumption, number of packets forwarded, end to end delay and packet delivery ratio compared to the existing routing protocol. PMID:26771586
An imperialist competitive algorithm for virtual machine placement in cloud computing

NASA Astrophysics Data System (ADS)

Jamali, Shahram; Malektaji, Sepideh; Analoui, Morteza

2017-05-01

Cloud computing, the recently emerged revolution in IT industry, is empowered by virtualisation technology. In this paradigm, the user's applications run over some virtual machines (VMs). The process of selecting proper physical machines to host these virtual machines is called virtual machine placement. It plays an important role on resource utilisation and power efficiency of cloud computing environment. In this paper, we propose an imperialist competitive-based algorithm for the virtual machine placement problem called ICA-VMPLC. The base optimisation algorithm is chosen to be ICA because of its ease in neighbourhood movement, good convergence rate and suitable terminology. The proposed algorithm investigates search space in a unique manner to efficiently obtain optimal placement solution that simultaneously minimises power consumption and total resource wastage. Its final solution performance is compared with several existing methods such as grouping genetic and ant colony-based algorithms as well as bin packing heuristic. The simulation results show that the proposed method is superior to other tested algorithms in terms of power consumption, resource wastage, CPU usage efficiency and memory usage efficiency.
A novel minimum cost maximum power algorithm for future smart home energy management.

PubMed

Singaravelan, A; Kowsalya, M

2017-11-01

With the latest development of smart grid technology, the energy management system can be efficiently implemented at consumer premises. In this paper, an energy management system with wireless communication and smart meter are designed for scheduling the electric home appliances efficiently with an aim of reducing the cost and peak demand. For an efficient scheduling scheme, the appliances are classified into two types: uninterruptible and interruptible appliances. The problem formulation was constructed based on the practical constraints that make the proposed algorithm cope up with the real-time situation. The formulated problem was identified as Mixed Integer Linear Programming (MILP) problem, so this problem was solved by a step-wise approach. This paper proposes a novel Minimum Cost Maximum Power (MCMP) algorithm to solve the formulated problem. The proposed algorithm was simulated with input data available in the existing method. For validating the proposed MCMP algorithm, results were compared with the existing method. The compared results prove that the proposed algorithm efficiently reduces the consumer electricity consumption cost and peak demand to optimum level with 100% task completion without sacrificing the consumer comfort.
Service-Aware Clustering: An Energy-Efficient Model for the Internet-of-Things

PubMed Central

Bagula, Antoine; Abidoye, Ademola Philip; Zodi, Guy-Alain Lusilao

2015-01-01

Current generation wireless sensor routing algorithms and protocols have been designed based on a myopic routing approach, where the motes are assumed to have the same sensing and communication capabilities. Myopic routing is not a natural fit for the IoT, as it may lead to energy imbalance and subsequent short-lived sensor networks, routing the sensor readings over the most service-intensive sensor nodes, while leaving the least active nodes idle. This paper revisits the issue of energy efficiency in sensor networks to propose a clustering model where sensor devices’ service delivery is mapped into an energy awareness model, used to design a clustering algorithm that finds service-aware clustering (SAC) configurations in IoT settings. The performance evaluation reveals the relative energy efficiency of the proposed SAC algorithm compared to related routing algorithms in terms of energy consumption, the sensor nodes’ life span and its traffic engineering efficiency in terms of throughput and delay. These include the well-known low energy adaptive clustering hierarchy (LEACH) and LEACH-centralized (LEACH-C) algorithms, as well as the most recent algorithms, such as DECSA and MOCRN. PMID:26703619
Service-Aware Clustering: An Energy-Efficient Model for the Internet-of-Things.

PubMed

Bagula, Antoine; Abidoye, Ademola Philip; Zodi, Guy-Alain Lusilao

2015-12-23

Current generation wireless sensor routing algorithms and protocols have been designed based on a myopic routing approach, where the motes are assumed to have the same sensing and communication capabilities. Myopic routing is not a natural fit for the IoT, as it may lead to energy imbalance and subsequent short-lived sensor networks, routing the sensor readings over the most service-intensive sensor nodes, while leaving the least active nodes idle. This paper revisits the issue of energy efficiency in sensor networks to propose a clustering model where sensor devices' service delivery is mapped into an energy awareness model, used to design a clustering algorithm that finds service-aware clustering (SAC) configurations in IoT settings. The performance evaluation reveals the relative energy efficiency of the proposed SAC algorithm compared to related routing algorithms in terms of energy consumption, the sensor nodes' life span and its traffic engineering efficiency in terms of throughput and delay. These include the well-known low energy adaptive clustering hierarchy (LEACH) and LEACH-centralized (LEACH-C) algorithms, as well as the most recent algorithms, such as DECSA and MOCRN.
Exploring the communication between telenurse and caller-a critical discourse analysis.

PubMed

Hakimnia, Roya; Holmström, Inger K; Carlsson, Marianne; Höglund, Anna T

2014-01-01

Telenursing is an expanding service in most Western societies. Sweden is a front-line country, with all of its 21 counties connected to Swedish Healthcare Direct (SHD) 1177. The intention of the service is twofold: to make health care more efficient, while also making it more accessible and safe for patients. Previous research has shown, however, that the service is not used equitably. Gender, age, socio-economic, and ethnicity differences have been reported as determining factors for the use of the service and the advice given. The aim of the study was to explore the communication between telenurses and callers in authentic calls to SHD 1177. A qualitative method, using critical discourse analysis (CDA), was chosen. The approach was deductive, that is, the analysis was made in view of a predetermined framework of theory. Twenty calls were strategically chosen and included in the study. The CDA resulted in five types of calls, namely a gatekeeping call, a gendered call, a call marked by impersonal traits, a call with voices of the life world, and finally a counter discourse call. The dominating patterns in the calls were of gatekeeping and biomedical character. Patterns of the societal gender order were found, in that representations of the reluctant male caller and the ideal female caller were identified, but also a call representing a counter discourse. The service seemed difficult to use for patients with low language proficiency. Telenursing could potentially challenge inequalities in health care. However, the discourse of telenursing is dialectically related to neoliberal ideology and the ideology of medicine. It is also situated in a gendered context of ideal femininity and hegemonic masculinity. Through better awareness of gender biases and the callers' different resources for making themselves heard, the communication between telenurse and caller might become more equal and thereby better suitable for all callers.
[Suicidal behavior prevention for children under age 13: A systematic review].

PubMed

Baux-Cazal, L; Gokalsing, E; Amadeo, S; Messiah, A

2017-05-01

Our objective was to review international literature on suicidal behavior prevention for children under age 13. We gathered all relevant articles on suicide prevention for children under 13. We researched all publications in the French and English languages in PubMed (MEDLINE), PsychINFO and SUDOC databases published until February 2014, with the keywords "child", "child preschool", "prevention and control", "suicide", and "suicide attempted". Publications were included if they described suicidal behavior prevention programs (suicide prevention programs, attempted-suicide prevention programs, suicidal ideation screening programs), and if the studies concerned children under age 13. We also included references cited in the articles if they were not already present in our searches but met inclusion criteria. Studies were excluded if they analyzed populations of children and adolescents without sub-analysis for children under age 13. A total of 350 potentially relevant articles were identified, 33 of which met the inclusion criteria, including 4 retrieved from articles' bibliography. Preventive measures against suicidal behavior for children under 13 exist and include: social programs, maltreatment prevention, curriculum-based suicide prevention programs, suicide screening in schools, gatekeepers, reduction of access of lethal means of suicide, suicide screening by primary care, and post-suicide intervention programs. Overall, the evidence was limited by methodological concerns, particularly a lack of RCTs. However, positive effects were found: school-based suicide prevention programs and gatekeepers increased knowledge about suicide and how to seek help, post-suicide programs helped to reduce psychological distress in the short term. One study showed a decreased risk of attempted-suicide after entry into the child welfare system. There are promising interventions but there is not enough scientific evidence to support any efficient preventive measure against suicidal behavior for children under 13, whether primary, secondary, tertiary or post-intervention. More research is needed. Copyright © 2016 L'Encéphale, Paris. Published by Elsevier Masson SAS. All rights reserved.
Cache and energy efficient algorithms for Nussinov's RNA Folding.

PubMed

Zhao, Chunchun; Sahni, Sartaj

2017-12-06

An RNA folding/RNA secondary structure prediction algorithm determines the non-nested/pseudoknot-free structure by maximizing the number of complementary base pairs and minimizing the energy. Several implementations of Nussinov's classical RNA folding algorithm have been proposed. Our focus is to obtain run time and energy efficiency by reducing the number of cache misses. Three cache-efficient algorithms, ByRow, ByRowSegment and ByBox, for Nussinov's RNA folding are developed. Using a simple LRU cache model, we show that the Classical algorithm of Nussinov has the highest number of cache misses followed by the algorithms Transpose (Li et al.), ByRow, ByRowSegment, and ByBox (in this order). Extensive experiments conducted on four computational platforms-Xeon E5, AMD Athlon 64 X2, Intel I7 and PowerPC A2-using two programming languages-C and Java-show that our cache efficient algorithms are also efficient in terms of run time and energy. Our benchmarking shows that, depending on the computational platform and programming language, either ByRow or ByBox give best run time and energy performance. The C version of these algorithms reduce run time by as much as 97.2% and energy consumption by as much as 88.8% relative to Classical and by as much as 56.3% and 57.8% relative to Transpose. The Java versions reduce run time by as much as 98.3% relative to Classical and by as much as 75.2% relative to Transpose. Transpose achieves run time and energy efficiency at the expense of memory as it takes twice the memory required by Classical. The memory required by ByRow, ByRowSegment, and ByBox is the same as that of Classical. As a result, using the same amount of memory, the algorithms proposed by us can solve problems up to 40% larger than those solvable by Transpose.
The admissible portfolio selection problem with transaction costs and an improved PSO algorithm

NASA Astrophysics Data System (ADS)

Chen, Wei; Zhang, Wei-Guo

2010-05-01

In this paper, we discuss the portfolio selection problem with transaction costs under the assumption that there exist admissible errors on expected returns and risks of assets. We propose a new admissible efficient portfolio selection model and design an improved particle swarm optimization (PSO) algorithm because traditional optimization algorithms fail to work efficiently for our proposed problem. Finally, we offer a numerical example to illustrate the proposed effective approaches and compare the admissible portfolio efficient frontiers under different constraints.
An efficient non-dominated sorting method for evolutionary algorithms.

PubMed

Fang, Hongbing; Wang, Qian; Tu, Yi-Cheng; Horstemeyer, Mark F

2008-01-01

We present a new non-dominated sorting algorithm to generate the non-dominated fronts in multi-objective optimization with evolutionary algorithms, particularly the NSGA-II. The non-dominated sorting algorithm used by NSGA-II has a time complexity of O(MN(2)) in generating non-dominated fronts in one generation (iteration) for a population size N and M objective functions. Since generating non-dominated fronts takes the majority of total computational time (excluding the cost of fitness evaluations) of NSGA-II, making this algorithm faster will significantly improve the overall efficiency of NSGA-II and other genetic algorithms using non-dominated sorting. The new non-dominated sorting algorithm proposed in this study reduces the number of redundant comparisons existing in the algorithm of NSGA-II by recording the dominance information among solutions from their first comparisons. By utilizing a new data structure called the dominance tree and the divide-and-conquer mechanism, the new algorithm is faster than NSGA-II for different numbers of objective functions. Although the number of solution comparisons by the proposed algorithm is close to that of NSGA-II when the number of objectives becomes large, the total computational time shows that the proposed algorithm still has better efficiency because of the adoption of the dominance tree structure and the divide-and-conquer mechanism.
Fast Ss-Ilm a Computationally Efficient Algorithm to Discover Socially Important Locations

NASA Astrophysics Data System (ADS)

Dokuz, A. S.; Celik, M.

2017-11-01

Socially important locations are places which are frequently visited by social media users in their social media lifetime. Discovering socially important locations provide several valuable information about user behaviours on social media networking sites. However, discovering socially important locations are challenging due to data volume and dimensions, spatial and temporal calculations, location sparseness in social media datasets, and inefficiency of current algorithms. In the literature, several studies are conducted to discover important locations, however, the proposed approaches do not work in computationally efficient manner. In this study, we propose Fast SS-ILM algorithm by modifying the algorithm of SS-ILM to mine socially important locations efficiently. Experimental results show that proposed Fast SS-ILM algorithm decreases execution time of socially important locations discovery process up to 20 %.
Dynamic graph cuts for efficient inference in Markov Random Fields.

PubMed

Kohli, Pushmeet; Torr, Philip H S

2007-12-01

Abstract-In this paper we present a fast new fully dynamic algorithm for the st-mincut/max-flow problem. We show how this algorithm can be used to efficiently compute MAP solutions for certain dynamically changing MRF models in computer vision such as image segmentation. Specifically, given the solution of the max-flow problem on a graph, the dynamic algorithm efficiently computes the maximum flow in a modified version of the graph. The time taken by it is roughly proportional to the total amount of change in the edge weights of the graph. Our experiments show that, when the number of changes in the graph is small, the dynamic algorithm is significantly faster than the best known static graph cut algorithm. We test the performance of our algorithm on one particular problem: the object-background segmentation problem for video. It should be noted that the application of our algorithm is not limited to the above problem, the algorithm is generic and can be used to yield similar improvements in many other cases that involve dynamic change.
Adaptive recurrence quantum entanglement distillation for two-Kraus-operator channels

NASA Astrophysics Data System (ADS)

Ruan, Liangzhong; Dai, Wenhan; Win, Moe Z.

2018-05-01

Quantum entanglement serves as a valuable resource for many important quantum operations. A pair of entangled qubits can be shared between two agents by first preparing a maximally entangled qubit pair at one agent, and then sending one of the qubits to the other agent through a quantum channel. In this process, the deterioration of entanglement is inevitable since the noise inherent in the channel contaminates the qubit. To address this challenge, various quantum entanglement distillation (QED) algorithms have been developed. Among them, recurrence algorithms have advantages in terms of implementability and robustness. However, the efficiency of recurrence QED algorithms has not been investigated thoroughly in the literature. This paper puts forth two recurrence QED algorithms that adapt to the quantum channel to tackle the efficiency issue. The proposed algorithms have guaranteed convergence for quantum channels with two Kraus operators, which include phase-damping and amplitude-damping channels. Analytical results show that the convergence speed of these algorithms is improved from linear to quadratic and one of the algorithms achieves the optimal speed. Numerical results confirm that the proposed algorithms significantly improve the efficiency of QED.

Extending Three-Dimensional Weighted Cone Beam Filtered Backprojection (CB-FBP) Algorithm for Image Reconstruction in Volumetric CT at Low Helical Pitches

PubMed Central

Hsieh, Jiang; Nilsen, Roy A.; McOlash, Scott M.

2006-01-01

A three-dimensional (3D) weighted helical cone beam filtered backprojection (CB-FBP) algorithm (namely, original 3D weighted helical CB-FBP algorithm) has already been proposed to reconstruct images from the projection data acquired along a helical trajectory in angular ranges up to [0, 2 π]. However, an overscan is usually employed in the clinic to reconstruct tomographic images with superior noise characteristics at the most challenging anatomic structures, such as head and spine, extremity imaging, and CT angiography as well. To obtain the most achievable noise characteristics or dose efficiency in a helical overscan, we extended the 3D weighted helical CB-FBP algorithm to handle helical pitches that are smaller than 1: 1 (namely extended 3D weighted helical CB-FBP algorithm). By decomposing a helical over scan with an angular range of [0, 2π + Δβ] into a union of full scans corresponding to an angular range of [0, 2π], the extended 3D weighted function is a summation of all 3D weighting functions corresponding to each full scan. An experimental evaluation shows that the extended 3D weighted helical CB-FBP algorithm can improve noise characteristics or dose efficiency of the 3D weighted helical CB-FBP algorithm at a helical pitch smaller than 1: 1, while its reconstruction accuracy and computational efficiency are maintained. It is believed that, such an efficient CB reconstruction algorithm that can provide superior noise characteristics or dose efficiency at low helical pitches may find its extensive applications in CT medical imaging. PMID:23165031
Nephrologists' perspectives on waitlisting and allocation of deceased donor kidneys for transplant.

PubMed

Tong, Allison; Howard, Kirsten; Wong, Germaine; Cass, Alan; Jan, Stephen; Irving, Michelle; Craig, Jonathan C

2011-11-01

Deceased donor kidneys are a scarce resource and there is debate about how to maximize the benefit from each donated kidney while ensuring equity of access to transplants. Allocation of kidneys to waitlisted patients is determined by a computer algorithm, but the decision to waitlist patients or accept the kidneys offered is largely at the discretion of nephrologists. This study aims to elicit nephrologists' perspectives on waitlisting patients for kidney transplant and the allocation of deceased kidneys. We conducted semistructured face-to-face interviews with adult and pediatric nephrologists from 15 Australian nephrology or transplant centers. Transcripts were analyzed for descriptive and analytical themes. 25 nephrologists participated. 5 major themes on waitlisting and deceased donor kidney allocation were identified: patient advocacy (championing their own patients, empowering patients, giving hope, individualizing judgments, patient preferences, and limited autonomy), professional and moral integrity (transparency, avoiding value judgments, and eliminating bias), protecting center reputation (gatekeeping), achieving equity (uniformity, avoiding discrimination, and fairness for specific populations), and maximizing societal benefit (prioritizing best use of kidney, resource implications, favoring social contribution, and improving efficiency of the allocation process). In making individual patient assessments, estimates about outcomes for a patient had to be resolved with whether it was reasonable from a broader societal perspective. Nephrologists expressed their primary responsibility in terms of giving their own patients access to a transplant and upholding professional integrity by maintaining transparency and avoiding value judgments and bias. However, nephrologists perceived an obligation to protect their center's reputation through the selection of "good" patients, and this caused some frustration. Despite having personal preferences for optimizing the balance between societal benefit and equity, nephrologists did not want direct responsibility for ensuring societal benefit in clinical practice. Rather, they placed the onus on policy makers and the community to reconcile such tensions and advocate for societal benefit. Copyright © 2011 National Kidney Foundation, Inc. Published by Elsevier Inc. All rights reserved.
76 FR 79379 - Risk-Based Capital Guidelines: Market Risk; Alternatives to Credit Ratings for Debt and...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-12-21

... play a critical ``gatekeeper'' role in the debt markets and perform evaluative and analytical services... assessments for fee-paying clients, nor does it provide the sort of evaluative and analytical services as...
An Efficient Randomized Algorithm for Real-Time Process Scheduling in PicOS Operating System

NASA Astrophysics Data System (ADS)

Helmy*, Tarek; Fatai, Anifowose; Sallam, El-Sayed

PicOS is an event-driven operating environment designed for use with embedded networked sensors. More specifically, it is designed to support the concurrency in intensive operations required by networked sensors with minimal hardware requirements. Existing process scheduling algorithms of PicOS; a commercial tiny, low-footprint, real-time operating system; have their associated drawbacks. An efficient, alternative algorithm, based on a randomized selection policy, has been proposed, demonstrated, confirmed for efficiency and fairness, on the average, and has been recommended for implementation in PicOS. Simulations were carried out and performance measures such as Average Waiting Time (AWT) and Average Turn-around Time (ATT) were used to assess the efficiency of the proposed randomized version over the existing ones. The results prove that Randomized algorithm is the best and most attractive for implementation in PicOS, since it is most fair and has the least AWT and ATT on average over the other non-preemptive scheduling algorithms implemented in this paper.
T-L Plane Abstraction-Based Energy-Efficient Real-Time Scheduling for Multi-Core Wireless Sensors

PubMed Central

Kim, Youngmin; Lee, Ki-Seong; Pham, Ngoc-Son; Lee, Sun-Ro; Lee, Chan-Gun

2016-01-01

Energy efficiency is considered as a critical requirement for wireless sensor networks. As more wireless sensor nodes are equipped with multi-cores, there are emerging needs for energy-efficient real-time scheduling algorithms. The T-L plane-based scheme is known to be an optimal global scheduling technique for periodic real-time tasks on multi-cores. Unfortunately, there has been a scarcity of studies on extending T-L plane-based scheduling algorithms to exploit energy-saving techniques. In this paper, we propose a new T-L plane-based algorithm enabling energy-efficient real-time scheduling on multi-core sensor nodes with dynamic power management (DPM). Our approach addresses the overhead of processor mode transitions and reduces fragmentations of the idle time, which are inherent in T-L plane-based algorithms. Our experimental results show the effectiveness of the proposed algorithm compared to other energy-aware scheduling methods on T-L plane abstraction. PMID:27399722
An Optimal CDS Construction Algorithm with Activity Scheduling in Ad Hoc Networks

PubMed Central

Penumalli, Chakradhar; Palanichamy, Yogesh

2015-01-01

A new energy efficient optimal Connected Dominating Set (CDS) algorithm with activity scheduling for mobile ad hoc networks (MANETs) is proposed. This algorithm achieves energy efficiency by minimizing the Broadcast Storm Problem [BSP] and at the same time considering the node's remaining energy. The Connected Dominating Set is widely used as a virtual backbone or spine in mobile ad hoc networks [MANETs] or Wireless Sensor Networks [WSN]. The CDS of a graph representing a network has a significant impact on an efficient design of routing protocol in wireless networks. Here the CDS is a distributed algorithm with activity scheduling based on unit disk graph [UDG]. The node's mobility and residual energy (RE) are considered as parameters in the construction of stable optimal energy efficient CDS. The performance is evaluated at various node densities, various transmission ranges, and mobility rates. The theoretical analysis and simulation results of this algorithm are also presented which yield better results. PMID:26221627
Joint Power Charging and Routing in Wireless Rechargeable Sensor Networks.

PubMed

Jia, Jie; Chen, Jian; Deng, Yansha; Wang, Xingwei; Aghvami, Abdol-Hamid

2017-10-09

The development of wireless power transfer (WPT) technology has inspired the transition from traditional battery-based wireless sensor networks (WSNs) towards wireless rechargeable sensor networks (WRSNs). While extensive efforts have been made to improve charging efficiency, little has been done for routing optimization. In this work, we present a joint optimization model to maximize both charging efficiency and routing structure. By analyzing the structure of the optimization model, we first decompose the problem and propose a heuristic algorithm to find the optimal charging efficiency for the predefined routing tree. Furthermore, by coding the many-to-one communication topology as an individual, we further propose to apply a genetic algorithm (GA) for the joint optimization of both routing and charging. The genetic operations, including tree-based recombination and mutation, are proposed to obtain a fast convergence. Our simulation results show that the heuristic algorithm reduces the number of resident locations and the total moving distance. We also show that our proposed algorithm achieves a higher charging efficiency compared with existing algorithms.
Joint Power Charging and Routing in Wireless Rechargeable Sensor Networks

PubMed Central

Jia, Jie; Chen, Jian; Deng, Yansha; Wang, Xingwei; Aghvami, Abdol-Hamid

2017-01-01

The development of wireless power transfer (WPT) technology has inspired the transition from traditional battery-based wireless sensor networks (WSNs) towards wireless rechargeable sensor networks (WRSNs). While extensive efforts have been made to improve charging efficiency, little has been done for routing optimization. In this work, we present a joint optimization model to maximize both charging efficiency and routing structure. By analyzing the structure of the optimization model, we first decompose the problem and propose a heuristic algorithm to find the optimal charging efficiency for the predefined routing tree. Furthermore, by coding the many-to-one communication topology as an individual, we further propose to apply a genetic algorithm (GA) for the joint optimization of both routing and charging. The genetic operations, including tree-based recombination and mutation, are proposed to obtain a fast convergence. Our simulation results show that the heuristic algorithm reduces the number of resident locations and the total moving distance. We also show that our proposed algorithm achieves a higher charging efficiency compared with existing algorithms. PMID:28991200
Efficient Learning Algorithms with Limited Information

ERIC Educational Resources Information Center

De, Anindya

2013-01-01

The thesis explores efficient learning algorithms in settings which are more restrictive than the PAC model of learning (Valiant) in one of the following two senses: (i) The learning algorithm has a very weak access to the unknown function, as in, it does not get labeled samples for the unknown function (ii) The error guarantee required from the…
Quantum partial search for uneven distribution of multiple target items

NASA Astrophysics Data System (ADS)

Zhang, Kun; Korepin, Vladimir

2018-06-01

Quantum partial search algorithm is an approximate search. It aims to find a target block (which has the target items). It runs a little faster than full Grover search. In this paper, we consider quantum partial search algorithm for multiple target items unevenly distributed in a database (target blocks have different number of target items). The algorithm we describe can locate one of the target blocks. Efficiency of the algorithm is measured by number of queries to the oracle. We optimize the algorithm in order to improve efficiency. By perturbation method, we find that the algorithm runs the fastest when target items are evenly distributed in database.
Efficient parallel and out of core algorithms for constructing large bi-directed de Bruijn graphs.

PubMed

Kundeti, Vamsi K; Rajasekaran, Sanguthevar; Dinh, Hieu; Vaughn, Matthew; Thapar, Vishal

2010-11-15

Assembling genomic sequences from a set of overlapping reads is one of the most fundamental problems in computational biology. Algorithms addressing the assembly problem fall into two broad categories - based on the data structures which they employ. The first class uses an overlap/string graph and the second type uses a de Bruijn graph. However with the recent advances in short read sequencing technology, de Bruijn graph based algorithms seem to play a vital role in practice. Efficient algorithms for building these massive de Bruijn graphs are very essential in large sequencing projects based on short reads. In an earlier work, an O(n/p) time parallel algorithm has been given for this problem. Here n is the size of the input and p is the number of processors. This algorithm enumerates all possible bi-directed edges which can overlap with a node and ends up generating Θ(nΣ) messages (Σ being the size of the alphabet). In this paper we present a Θ(n/p) time parallel algorithm with a communication complexity that is equal to that of parallel sorting and is not sensitive to Σ. The generality of our algorithm makes it very easy to extend it even to the out-of-core model and in this case it has an optimal I/O complexity of Θ(nlog(n/B)Blog(M/B)) (M being the main memory size and B being the size of the disk block). We demonstrate the scalability of our parallel algorithm on a SGI/Altix computer. A comparison of our algorithm with the previous approaches reveals that our algorithm is faster--both asymptotically and practically. We demonstrate the scalability of our sequential out-of-core algorithm by comparing it with the algorithm used by VELVET to build the bi-directed de Bruijn graph. Our experiments reveal that our algorithm can build the graph with a constant amount of memory, which clearly outperforms VELVET. We also provide efficient algorithms for the bi-directed chain compaction problem. The bi-directed de Bruijn graph is a fundamental data structure for any sequence assembly program based on Eulerian approach. Our algorithms for constructing Bi-directed de Bruijn graphs are efficient in parallel and out of core settings. These algorithms can be used in building large scale bi-directed de Bruijn graphs. Furthermore, our algorithms do not employ any all-to-all communications in a parallel setting and perform better than the prior algorithms. Finally our out-of-core algorithm is extremely memory efficient and can replace the existing graph construction algorithm in VELVET.
Gradient gravitational search: An efficient metaheuristic algorithm for global optimization.

PubMed

Dash, Tirtharaj; Sahu, Prabhat K

2015-05-30

The adaptation of novel techniques developed in the field of computational chemistry to solve the concerned problems for large and flexible molecules is taking the center stage with regard to efficient algorithm, computational cost and accuracy. In this article, the gradient-based gravitational search (GGS) algorithm, using analytical gradients for a fast minimization to the next local minimum has been reported. Its efficiency as metaheuristic approach has also been compared with Gradient Tabu Search and others like: Gravitational Search, Cuckoo Search, and Back Tracking Search algorithms for global optimization. Moreover, the GGS approach has also been applied to computational chemistry problems for finding the minimal value potential energy of two-dimensional and three-dimensional off-lattice protein models. The simulation results reveal the relative stability and physical accuracy of protein models with efficient computational cost. © 2015 Wiley Periodicals, Inc.
Efficient convolutional sparse coding

DOEpatents

Wohlberg, Brendt

2017-06-20

Computationally efficient algorithms may be applied for fast dictionary learning solving the convolutional sparse coding problem in the Fourier domain. More specifically, efficient convolutional sparse coding may be derived within an alternating direction method of multipliers (ADMM) framework that utilizes fast Fourier transforms (FFT) to solve the main linear system in the frequency domain. Such algorithms may enable a significant reduction in computational cost over conventional approaches by implementing a linear solver for the most critical and computationally expensive component of the conventional iterative algorithm. The theoretical computational cost of the algorithm may be reduced from O(M.sup.3N) to O(MN log N), where N is the dimensionality of the data and M is the number of elements in the dictionary. This significant improvement in efficiency may greatly increase the range of problems that can practically be addressed via convolutional sparse representations.
Efficient Modeling of Gravity Fields Caused by Sources with Arbitrary Geometry and Arbitrary Density Distribution

NASA Astrophysics Data System (ADS)

Wu, Leyuan

2018-01-01

We present a brief review of gravity forward algorithms in Cartesian coordinate system, including both space-domain and Fourier-domain approaches, after which we introduce a truly general and efficient algorithm, namely the convolution-type Gauss fast Fourier transform (Conv-Gauss-FFT) algorithm, for 2D and 3D modeling of gravity potential and its derivatives due to sources with arbitrary geometry and arbitrary density distribution which are defined either by discrete or by continuous functions. The Conv-Gauss-FFT algorithm is based on the combined use of a hybrid rectangle-Gaussian grid and the fast Fourier transform (FFT) algorithm. Since the gravity forward problem in Cartesian coordinate system can be expressed as continuous convolution-type integrals, we first approximate the continuous convolution by a weighted sum of a series of shifted discrete convolutions, and then each shifted discrete convolution, which is essentially a Toeplitz system, is calculated efficiently and accurately by combining circulant embedding with the FFT algorithm. Synthetic and real model tests show that the Conv-Gauss-FFT algorithm can obtain high-precision forward results very efficiently for almost any practical model, and it works especially well for complex 3D models when gravity fields on large 3D regular grids are needed.
Incremental k-core decomposition: Algorithms and evaluation

DOE PAGES

Sariyuce, Ahmet Erdem; Gedik, Bugra; Jacques-SIlva, Gabriela; ...

2016-02-01

A k-core of a graph is a maximal connected subgraph in which every vertex is connected to at least k vertices in the subgraph. k-core decomposition is often used in large-scale network analysis, such as community detection, protein function prediction, visualization, and solving NP-hard problems on real networks efficiently, like maximal clique finding. In many real-world applications, networks change over time. As a result, it is essential to develop efficient incremental algorithms for dynamic graph data. In this paper, we propose a suite of incremental k-core decomposition algorithms for dynamic graph data. These algorithms locate a small subgraph that ismore » guaranteed to contain the list of vertices whose maximum k-core values have changed and efficiently process this subgraph to update the k-core decomposition. We present incremental algorithms for both insertion and deletion operations, and propose auxiliary vertex state maintenance techniques that can further accelerate these operations. Our results show a significant reduction in runtime compared to non-incremental alternatives. We illustrate the efficiency of our algorithms on different types of real and synthetic graphs, at varying scales. Furthermore, for a graph of 16 million vertices, we observe relative throughputs reaching a million times, relative to the non-incremental algorithms.« less
Army ants algorithm for rare event sampling of delocalized nonadiabatic transitions by trajectory surface hopping and the estimation of sampling errors by the bootstrap method.

PubMed

Nangia, Shikha; Jasper, Ahren W; Miller, Thomas F; Truhlar, Donald G

2004-02-22

The most widely used algorithm for Monte Carlo sampling of electronic transitions in trajectory surface hopping (TSH) calculations is the so-called anteater algorithm, which is inefficient for sampling low-probability nonadiabatic events. We present a new sampling scheme (called the army ants algorithm) for carrying out TSH calculations that is applicable to systems with any strength of coupling. The army ants algorithm is a form of rare event sampling whose efficiency is controlled by an input parameter. By choosing a suitable value of the input parameter the army ants algorithm can be reduced to the anteater algorithm (which is efficient for strongly coupled cases), and by optimizing the parameter the army ants algorithm may be efficiently applied to systems with low-probability events. To demonstrate the efficiency of the army ants algorithm, we performed atom-diatom scattering calculations on a model system involving weakly coupled electronic states. Fully converged quantum mechanical calculations were performed, and the probabilities for nonadiabatic reaction and nonreactive deexcitation (quenching) were found to be on the order of 10(-8). For such low-probability events the anteater sampling scheme requires a large number of trajectories ( approximately 10(10)) to obtain good statistics and converged semiclassical results. In contrast by using the new army ants algorithm converged results were obtained by running 10(5) trajectories. Furthermore, the results were found to be in excellent agreement with the quantum mechanical results. Sampling errors were estimated using the bootstrap method, which is validated for use with the army ants algorithm. (c) 2004 American Institute of Physics.
Efficient convex-elastic net algorithm to solve the Euclidean traveling salesman problem.

PubMed

Al-Mulhem, M; Al-Maghrabi, T

1998-01-01

This paper describes a hybrid algorithm that combines an adaptive-type neural network algorithm and a nondeterministic iterative algorithm to solve the Euclidean traveling salesman problem (E-TSP). It begins with a brief introduction to the TSP and the E-TSP. Then, it presents the proposed algorithm with its two major components: the convex-elastic net (CEN) algorithm and the nondeterministic iterative improvement (NII) algorithm. These two algorithms are combined into the efficient convex-elastic net (ECEN) algorithm. The CEN algorithm integrates the convex-hull property and elastic net algorithm to generate an initial tour for the E-TSP. The NII algorithm uses two rearrangement operators to improve the initial tour given by the CEN algorithm. The paper presents simulation results for two instances of E-TSP: randomly generated tours and tours for well-known problems in the literature. Experimental results are given to show that the proposed algorithm ran find the nearly optimal solution for the E-TSP that outperform many similar algorithms reported in the literature. The paper concludes with the advantages of the new algorithm and possible extensions.
Traveling-Wave Tube Efficiency Enhancement

NASA Technical Reports Server (NTRS)

Dayton, James A., Jr.

2011-01-01

Traveling-wave tubes (TWT's) are used to amplify microwave communication signals on virtually all NASA and commercial spacecraft. Because TWT's are a primary power user, increasing their power efficiency is important for reducing spacecraft weight and cost. NASA Glenn Research Center has played a major role in increasing TWT efficiency over the last thirty years. In particular, two types of efficiency optimization algorithms have been developed for coupled-cavity TWT's. The first is the phase-adjusted taper which was used to increase the RF power from 420 to 1000 watts and the RF efficiency from 9.6% to 22.6% for a Ka-band (29.5 GHz) TWT. This was a record efficiency at this frequency level. The second is an optimization algorithm based on simulated annealing. This improved algorithm is more general and can be used to optimize efficiency over a frequency bandwidth and to provide a robust design for very high frequency TWT's in which dimensional tolerance variations are significant.
Struggles of the Novice Counselor and Therapists.

ERIC Educational Resources Information Center

Skovholt, Thomas M.; Ronnestad, Michael H.

2003-01-01

Review of theory and research on counselor/therapist development identified seven stressors of novice practitioners, catalyzed by the ambiguity of professional work. Sources of stress include acute performance anxiety, scrutiny of professional gatekeepers, porous or rigid emotional boundaries, fragile and incomplete practitioner identity,…
Efficient least angle regression for identification of linear-in-the-parameters models

PubMed Central

Beach, Thomas H.; Rezgui, Yacine

2017-01-01

Least angle regression, as a promising model selection method, differentiates itself from conventional stepwise and stagewise methods, in that it is neither too greedy nor too slow. It is closely related to L1 norm optimization, which has the advantage of low prediction variance through sacrificing part of model bias property in order to enhance model generalization capability. In this paper, we propose an efficient least angle regression algorithm for model selection for a large class of linear-in-the-parameters models with the purpose of accelerating the model selection process. The entire algorithm works completely in a recursive manner, where the correlations between model terms and residuals, the evolving directions and other pertinent variables are derived explicitly and updated successively at every subset selection step. The model coefficients are only computed when the algorithm finishes. The direct involvement of matrix inversions is thereby relieved. A detailed computational complexity analysis indicates that the proposed algorithm possesses significant computational efficiency, compared with the original approach where the well-known efficient Cholesky decomposition is involved in solving least angle regression. Three artificial and real-world examples are employed to demonstrate the effectiveness, efficiency and numerical stability of the proposed algorithm. PMID:28293140

Efficient Parallel Algorithm For Direct Numerical Simulation of Turbulent Flows

NASA Technical Reports Server (NTRS)

Moitra, Stuti; Gatski, Thomas B.

1997-01-01

A distributed algorithm for a high-order-accurate finite-difference approach to the direct numerical simulation (DNS) of transition and turbulence in compressible flows is described. This work has two major objectives. The first objective is to demonstrate that parallel and distributed-memory machines can be successfully and efficiently used to solve computationally intensive and input/output intensive algorithms of the DNS class. The second objective is to show that the computational complexity involved in solving the tridiagonal systems inherent in the DNS algorithm can be reduced by algorithm innovations that obviate the need to use a parallelized tridiagonal solver.
Error and Symmetry Analysis of Misner's Algorithm for Spherical Harmonic Decomposition on a Cubic Grid

NASA Technical Reports Server (NTRS)

Fiske, David R.

2004-01-01

In an earlier paper, Misner (2004, Class. Quant. Grav., 21, S243) presented a novel algorithm for computing the spherical harmonic components of data represented on a cubic grid. I extend Misner s original analysis by making detailed error estimates of the numerical errors accrued by the algorithm, by using symmetry arguments to suggest a more efficient implementation scheme, and by explaining how the algorithm can be applied efficiently on data with explicit reflection symmetries.
Moving beyond the Typologies of Managed Care: The Example of Health Plan Predictors of Screening Mammography

PubMed Central

Tye, Sherilyn; Phillips, Kathryn A; Liang, Su-Ying; Haas, Jennifer S

2004-01-01

Objectives To develop a framework of factors to characterize health plans, to identify how plan characteristics were measured in a national survey, and to apply our findings to an analysis of the predictors of screening mammography. Data Source The primary data were from the 1996 Medical Expenditure Panel Survey. Study Design Women ages 40+, with private insurance, and no history of breast cancer were included in the study (N=2,909). We used multivariate logistic regression to estimate mammography utilization in the past two years relative to health plan and demographic factors. Health plan measures included whether there is a defined provider network, whether coverage is restricted to a network, use of gatekeepers, level of cost containment, copayment and deductible amounts, coinsurance rate, and breadth of benefit coverage. Principal Findings We found no significant difference in reported mammography utilization using a dichotomous comparison of individuals enrolled in managed care versus indemnity plans. However, women in health plans with a defined provider network were more likely to report having received a mammogram in the past two years than those without networks (adjusted OR=1.21, 95 percent CI=1.07–1.36), and women in gatekeeper plans were more likely to report receiving mammography than those without gatekeepers (adjusted OR=1.18, 95 percent CI=1.03–1.36). Restricted out-of-network coverage, use of cost containment, enrollee cost sharing, and breadth of benefit coverage did not appear to affect mammography use. Conclusions It is important to examine the effect of individual health plan components on the utilization of health care, rather than use the traditional broader categorizations of managed versus nonmanaged care or simple health plan typologies. PMID:14965083
I/O efficient algorithms and applications in geographic information systems

NASA Astrophysics Data System (ADS)

Danner, Andrew

Modern remote sensing methods such a laser altimetry (lidar) and Interferometric Synthetic Aperture Radar (IfSAR) produce georeferenced elevation data at unprecedented rates. Many Geographic Information System (GIS) algorithms designed for terrain modelling applications cannot process these massive data sets. The primary problem is that these data sets are too large to fit in the main internal memory of modern computers and must therefore reside on larger, but considerably slower disks. In these applications, the transfer of data between disk and main memory, or I/O, becomes the primary bottleneck. Working in a theoretical model that more accurately represents this two level memory hierarchy, we can develop algorithms that are I/O-efficient and reduce the amount of disk I/O needed to solve a problem. In this thesis we aim to modernize GIS algorithms and develop a number of I/O-efficient algorithms for processing geographic data derived from massive elevation data sets. For each application, we convert a geographic question to an algorithmic question, develop an I/O-efficient algorithm that is theoretically efficient, implement our approach and verify its performance using real-world data. The applications we consider include constructing a gridded digital elevation model (DEM) from an irregularly spaced point cloud, removing topological noise from a DEM, modeling surface water flow over a terrain, extracting river networks and watershed hierarchies from the terrain, and locating polygons containing query points in a planar subdivision. We initially developed solutions to each of these applications individually. However, we also show how to combine individual solutions to form a scalable geo-processing pipeline that seamlessly solves a sequence of sub-problems with little or no manual intervention. We present experimental results that demonstrate orders of magnitude improvement over previously known algorithms.
Single-step reinitialization and extending algorithms for level-set based multi-phase flow simulations

NASA Astrophysics Data System (ADS)

Fu, Lin; Hu, Xiangyu Y.; Adams, Nikolaus A.

2017-12-01

We propose efficient single-step formulations for reinitialization and extending algorithms, which are critical components of level-set based interface-tracking methods. The level-set field is reinitialized with a single-step (non iterative) "forward tracing" algorithm. A minimum set of cells is defined that describes the interface, and reinitialization employs only data from these cells. Fluid states are extrapolated or extended across the interface by a single-step "backward tracing" algorithm. Both algorithms, which are motivated by analogy to ray-tracing, avoid multiple block-boundary data exchanges that are inevitable for iterative reinitialization and extending approaches within a parallel-computing environment. The single-step algorithms are combined with a multi-resolution conservative sharp-interface method and validated by a wide range of benchmark test cases. We demonstrate that the proposed reinitialization method achieves second-order accuracy in conserving the volume of each phase. The interface location is invariant to reapplication of the single-step reinitialization. Generally, we observe smaller absolute errors than for standard iterative reinitialization on the same grid. The computational efficiency is higher than for the standard and typical high-order iterative reinitialization methods. We observe a 2- to 6-times efficiency improvement over the standard method for serial execution. The proposed single-step extending algorithm, which is commonly employed for assigning data to ghost cells with ghost-fluid or conservative interface interaction methods, shows about 10-times efficiency improvement over the standard method while maintaining same accuracy. Despite their simplicity, the proposed algorithms offer an efficient and robust alternative to iterative reinitialization and extending methods for level-set based multi-phase simulations.
New algorithms for solving high even-order differential equations using third and fourth Chebyshev-Galerkin methods

NASA Astrophysics Data System (ADS)

Doha, E. H.; Abd-Elhameed, W. M.; Bassuony, M. A.

2013-03-01

This paper is concerned with spectral Galerkin algorithms for solving high even-order two point boundary value problems in one dimension subject to homogeneous and nonhomogeneous boundary conditions. The proposed algorithms are extended to solve two-dimensional high even-order differential equations. The key to the efficiency of these algorithms is to construct compact combinations of Chebyshev polynomials of the third and fourth kinds as basis functions. The algorithms lead to linear systems with specially structured matrices that can be efficiently inverted. Numerical examples are included to demonstrate the validity and applicability of the proposed algorithms, and some comparisons with some other methods are made.
An Improved Vision-based Algorithm for Unmanned Aerial Vehicles Autonomous Landing

NASA Astrophysics Data System (ADS)

Zhao, Yunji; Pei, Hailong

In vision-based autonomous landing system of UAV, the efficiency of target detecting and tracking will directly affect the control system. The improved algorithm of SURF(Speed Up Robust Features) will resolve the problem which is the inefficiency of the SURF algorithm in the autonomous landing system. The improved algorithm is composed of three steps: first, detect the region of the target using the Camshift; second, detect the feature points in the region of the above acquired using the SURF algorithm; third, do the matching between the template target and the region of target in frame. The results of experiment and theoretical analysis testify the efficiency of the algorithm.
A cellular automata based FPGA realization of a new metaheuristic bat-inspired algorithm

NASA Astrophysics Data System (ADS)

Progias, Pavlos; Amanatiadis, Angelos A.; Spataro, William; Trunfio, Giuseppe A.; Sirakoulis, Georgios Ch.

2016-10-01

Optimization algorithms are often inspired by processes occuring in nature, such as animal behavioral patterns. The main concern with implementing such algorithms in software is the large amounts of processing power they require. In contrast to software code, that can only perform calculations in a serial manner, an implementation in hardware, exploiting the inherent parallelism of single-purpose processors, can prove to be much more efficient both in speed and energy consumption. Furthermore, the use of Cellular Automata (CA) in such an implementation would be efficient both as a model for natural processes, as well as a computational paradigm implemented well on hardware. In this paper, we propose a VHDL implementation of a metaheuristic algorithm inspired by the echolocation behavior of bats. More specifically, the CA model is inspired by the metaheuristic algorithm proposed earlier in the literature, which could be considered at least as efficient than other existing optimization algorithms. The function of the FPGA implementation of our algorithm is explained in full detail and results of our simulations are also demonstrated.
Regional-scale calculation of the LS factor using parallel processing

NASA Astrophysics Data System (ADS)

Liu, Kai; Tang, Guoan; Jiang, Ling; Zhu, A.-Xing; Yang, Jianyi; Song, Xiaodong

2015-05-01

With the increase of data resolution and the increasing application of USLE over large areas, the existing serial implementation of algorithms for computing the LS factor is becoming a bottleneck. In this paper, a parallel processing model based on message passing interface (MPI) is presented for the calculation of the LS factor, so that massive datasets at a regional scale can be processed efficiently. The parallel model contains algorithms for calculating flow direction, flow accumulation, drainage network, slope, slope length and the LS factor. According to the existence of data dependence, the algorithms are divided into local algorithms and global algorithms. Parallel strategy are designed according to the algorithm characters including the decomposition method for maintaining the integrity of the results, optimized workflow for reducing the time taken for exporting the unnecessary intermediate data and a buffer-communication-computation strategy for improving the communication efficiency. Experiments on a multi-node system show that the proposed parallel model allows efficient calculation of the LS factor at a regional scale with a massive dataset.
An Improved Scheduling Algorithm for Data Transmission in Ultrasonic Phased Arrays with Multi-Group Ultrasonic Sensors

PubMed Central

Tang, Wenming; Liu, Guixiong; Li, Yuzhong; Tan, Daji

2017-01-01

High data transmission efficiency is a key requirement for an ultrasonic phased array with multi-group ultrasonic sensors. Here, a novel FIFOs scheduling algorithm was proposed and the data transmission efficiency with hardware technology was improved. This algorithm includes FIFOs as caches for the ultrasonic scanning data obtained from the sensors with the output data in a bandwidth-sharing way, on the basis of which an optimal length ratio of all the FIFOs is achieved, allowing the reading operations to be switched among all the FIFOs without time slot waiting. Therefore, this algorithm enhances the utilization ratio of the reading bandwidth resources so as to obtain higher efficiency than the traditional scheduling algorithms. The reliability and validity of the algorithm are substantiated after its implementation in the field programmable gate array (FPGA) technology, and the bandwidth utilization ratio and the real-time performance of the ultrasonic phased array are enhanced. PMID:29035345
Evaluation of Genetic Algorithm Concepts Using Model Problems. Part 2; Multi-Objective Optimization

NASA Technical Reports Server (NTRS)

Holst, Terry L.; Pulliam, Thomas H.

2003-01-01

A genetic algorithm approach suitable for solving multi-objective optimization problems is described and evaluated using a series of simple model problems. Several new features including a binning selection algorithm and a gene-space transformation procedure are included. The genetic algorithm is suitable for finding pareto optimal solutions in search spaces that are defined by any number of genes and that contain any number of local extrema. Results indicate that the genetic algorithm optimization approach is flexible in application and extremely reliable, providing optimal results for all optimization problems attempted. The binning algorithm generally provides pareto front quality enhancements and moderate convergence efficiency improvements for most of the model problems. The gene-space transformation procedure provides a large convergence efficiency enhancement for problems with non-convoluted pareto fronts and a degradation in efficiency for problems with convoluted pareto fronts. The most difficult problems --multi-mode search spaces with a large number of genes and convoluted pareto fronts-- require a large number of function evaluations for GA convergence, but always converge.
PS-FW: A Hybrid Algorithm Based on Particle Swarm and Fireworks for Global Optimization

PubMed Central

Chen, Shuangqing; Wei, Lixin; Guan, Bing

2018-01-01

Particle swarm optimization (PSO) and fireworks algorithm (FWA) are two recently developed optimization methods which have been applied in various areas due to their simplicity and efficiency. However, when being applied to high-dimensional optimization problems, PSO algorithm may be trapped in the local optima owing to the lack of powerful global exploration capability, and fireworks algorithm is difficult to converge in some cases because of its relatively low local exploitation efficiency for noncore fireworks. In this paper, a hybrid algorithm called PS-FW is presented, in which the modified operators of FWA are embedded into the solving process of PSO. In the iteration process, the abandonment and supplement mechanism is adopted to balance the exploration and exploitation ability of PS-FW, and the modified explosion operator and the novel mutation operator are proposed to speed up the global convergence and to avoid prematurity. To verify the performance of the proposed PS-FW algorithm, 22 high-dimensional benchmark functions have been employed, and it is compared with PSO, FWA, stdPSO, CPSO, CLPSO, FIPS, Frankenstein, and ALWPSO algorithms. Results show that the PS-FW algorithm is an efficient, robust, and fast converging optimization method for solving global optimization problems. PMID:29675036
Fast parallel algorithm for slicing STL based on pipeline

NASA Astrophysics Data System (ADS)

Ma, Xulong; Lin, Feng; Yao, Bo

2016-05-01

In Additive Manufacturing field, the current researches of data processing mainly focus on a slicing process of large STL files or complicated CAD models. To improve the efficiency and reduce the slicing time, a parallel algorithm has great advantages. However, traditional algorithms can't make full use of multi-core CPU hardware resources. In the paper, a fast parallel algorithm is presented to speed up data processing. A pipeline mode is adopted to design the parallel algorithm. And the complexity of the pipeline algorithm is analyzed theoretically. To evaluate the performance of the new algorithm, effects of threads number and layers number are investigated by a serial of experiments. The experimental results show that the threads number and layers number are two remarkable factors to the speedup ratio. The tendency of speedup versus threads number reveals a positive relationship which greatly agrees with the Amdahl's law, and the tendency of speedup versus layers number also keeps a positive relationship agreeing with Gustafson's law. The new algorithm uses topological information to compute contours with a parallel method of speedup. Another parallel algorithm based on data parallel is used in experiments to show that pipeline parallel mode is more efficient. A case study at last shows a suspending performance of the new parallel algorithm. Compared with the serial slicing algorithm, the new pipeline parallel algorithm can make full use of the multi-core CPU hardware, accelerate the slicing process, and compared with the data parallel slicing algorithm, the new slicing algorithm in this paper adopts a pipeline parallel model, and a much higher speedup ratio and efficiency is achieved.
A new BP Fourier algorithm and its application in English teaching evaluation

NASA Astrophysics Data System (ADS)

Pei, Xuehui; Pei, Guixin

2017-08-01

BP neural network algorithm has wide adaptability and accuracy when used in complicated system evaluation, but its calculation defects such as slow convergence have limited its practical application. The paper tries to speed up the calculation convergence of BP neural network algorithm with Fourier basis functions and presents a new BP Fourier algorithm for complicated system evaluation. First, shortages and working principle of BP algorithm are analyzed for subsequent targeted improvement; Second, the presented BP Fourier algorithm adopts Fourier basis functions to simplify calculation structure, designs new calculation transfer function between input and output layers, and conducts theoretical analysis to prove the efficiency of the presented algorithm; Finally, the presented algorithm is used in evaluating university English teaching and the application results shows that the presented BP Fourier algorithm has better performance in calculation efficiency and evaluation accuracy and can be used in evaluating complicated system practically.
Efficient super-resolution image reconstruction applied to surveillance video captured by small unmanned aircraft systems

NASA Astrophysics Data System (ADS)

He, Qiang; Schultz, Richard R.; Chu, Chee-Hung Henry

2008-04-01

The concept surrounding super-resolution image reconstruction is to recover a highly-resolved image from a series of low-resolution images via between-frame subpixel image registration. In this paper, we propose a novel and efficient super-resolution algorithm, and then apply it to the reconstruction of real video data captured by a small Unmanned Aircraft System (UAS). Small UAS aircraft generally have a wingspan of less than four meters, so that these vehicles and their payloads can be buffeted by even light winds, resulting in potentially unstable video. This algorithm is based on a coarse-to-fine strategy, in which a coarsely super-resolved image sequence is first built from the original video data by image registration and bi-cubic interpolation between a fixed reference frame and every additional frame. It is well known that the median filter is robust to outliers. If we calculate pixel-wise medians in the coarsely super-resolved image sequence, we can restore a refined super-resolved image. The primary advantage is that this is a noniterative algorithm, unlike traditional approaches based on highly-computational iterative algorithms. Experimental results show that our coarse-to-fine super-resolution algorithm is not only robust, but also very efficient. In comparison with five well-known super-resolution algorithms, namely the robust super-resolution algorithm, bi-cubic interpolation, projection onto convex sets (POCS), the Papoulis-Gerchberg algorithm, and the iterated back projection algorithm, our proposed algorithm gives both strong efficiency and robustness, as well as good visual performance. This is particularly useful for the application of super-resolution to UAS surveillance video, where real-time processing is highly desired.
A Simulated Annealing Algorithm for the Optimization of Multistage Depressed Collector Efficiency

NASA Technical Reports Server (NTRS)

Vaden, Karl R.; Wilson, Jeffrey D.; Bulson, Brian A.

2002-01-01

The microwave traveling wave tube amplifier (TWTA) is widely used as a high-power transmitting source for space and airborne communications. One critical factor in designing a TWTA is the overall efficiency. However, overall efficiency is highly dependent upon collector efficiency; so collector design is critical to the performance of a TWTA. Therefore, NASA Glenn Research Center has developed an optimization algorithm based on Simulated Annealing to quickly design highly efficient multi-stage depressed collectors (MDC).
A Worked Example for Creating Worked Examples

ERIC Educational Resources Information Center

McGinn, Kelly M.; Lange, Karin E.; Booth, Julie L.

2015-01-01

Researchers have extensively documented, and math teachers know from experience, that algebra is a "gatekeeper" to more advanced mathematical topics. Students must have a strong understanding of fundamental algebraic concepts to be successful in later mathematics courses. Unfortunately, algebraic misconceptions that students may form or…
The Moral Education of Journal Editors

ERIC Educational Resources Information Center

Krimsky, Sheldon

2010-01-01

Refereed journals in science and medicine are the gatekeepers and repositories of knowledge in their respective fields. Research reported in peer-reviewed journals builds professional careers, determines which drugs and medical devices are licensed, influences what medical treatments become standards of care, and establishes the veracity of…
A Randomized Control Trial of a Community Mental Health Intervention for Military Personnel

DTIC Science & Technology

2013-10-01

reporting period. 15. SUBJECT TERMS Mental health literacy , Mental Health First Aid (MHFA), curriculum adaptation 16. SECURITY CLASSIFICATION OF...Stress First Aid and suicide prevention gatekeeper training by providing a mental health literacy component that is currently not addressed
Open Education as a "Heterotopia of Desire"

ERIC Educational Resources Information Center

Gourlay, Lesley

2015-01-01

The movement towards "openness" in education has tended to position itself as inherently democratising, radical, egalitarian and critical of powerful gatekeepers to learning. While "openness" is often positioned as a critique, I will argue that its mainstream discourses--while appearing to oppose large-scale operations of…

Administrative gatekeeping - a third way between unrestricted patient advocacy and bedside rationing.

PubMed

Lauridsen, Sigurd

2009-06-01

The inevitable need for rationing of healthcare has apparently presented the medical profession with the dilemma of choosing the lesser of two evils. Physicians appear to be obliged to adopt either an implausible version of traditional professional ethics or an equally problematic ethics of bedside rationing. The former requires unrestricted advocacy of patients but prompts distrust, moral hazard and unfairness. The latter commits physicians to rationing at the bedside; but it is bound to introduce unfair inequalities among patients and lack of political accountability towards citizens. In this paper I shall argue that this dilemma is false, since a third intermediate alternative exists. This alternative, which I term 'administrative gatekeeping', makes it possible for physicians to be involved in rationing while at the same time being genuine advocates of their patients. According to this ideal, physicians are required to follow fair rules of rationing adopted at higher organizational levels within healthcare systems. At the same time, however, they are prohibited from including considerations of cost in their clinical decisions.
“Enjoy Your Sexuality, but Do it in Secret”: Exploring Undergraduate Women’s Reports of Friends’ Sexual Communications

PubMed Central

Trinh, Sarah L.

2015-01-01

In the current study I used mixed methods to explore the messages that undergraduate women (n = 415) reported receiving from their male and female friends regarding sex and romantic relationships. Reports of friends’ messages varied widely and entailed both support for and criticism of sexual gatekeeping and sex positivity (e.g., sexual agency) and advice regarding sex and romantic relationships. Four individuals, including the author, developed codes to examine this wide range of responses to sexual expectations and prohibitions and independently and reliably coded the data. Response patterns illustrate that reports of female friends’ messages were typically longer and more nuanced than reports of male friends’ messages. Sex-positive messages and sexual gatekeeping messages were frequently reported simultaneously, and this pattern of co-occurrence illustrates the tensions between diverse discourses regarding women’s sexuality. The diversity in reports of friends’ messages challenges popular notions that friends’ influences are wholly problematic and highlights a need for more gender-focused sex education curricula. PMID:27092014
Defining and Negotiating the Social Value of Research in Public Health Facilities: Perceptions of Stakeholders in a Research-Active Province of South Africa.

PubMed

Lutge, Elizabeth; Slack, Catherine; Wassenaar, Douglas

2017-02-01

This article reports on qualitative research conducted in KwaZulu-Natal, South Africa, among researchers and gate-keepers of health facilities in the province. Results suggest disparate but not irreconcilable perceptions of the social value of research in provincial health facilities. This study found that researchers tended to emphasize the contribution of research to the generation of knowledge and to the health of future patients while gate-keepers of health facilities tended to emphasize its contribution to the healthcare system and to current patients. Furthermore, relations between research stakeholders were perceived to be somewhat fragile, making it difficult for stakeholders to achieve consensus about the social value of research, as well as on ways to maximize value. Interventions to negotiate a shared perspective on the social value of research would appear to be warranted, and the findings of this study suggest some focus areas for such intervention. © 2017 John Wiley & Sons Ltd.
Positive Feedback From Male Authority Figures Boosts Women's Math Outcomes.

PubMed

Park, Lora E; Kondrak, Cheryl L; Ward, Deborah E; Streamer, Lindsey

2018-03-01

People often search for cues in the environment to determine whether or not they will be judged or treated negatively based on their social identities. Accordingly, feedback from gatekeepers-members of majority groups who hold authority and power in a field-may be an especially important cue for those at risk of experiencing social identity threat, such as women in math settings. Across a series of studies, women who received positive ("Good job!") versus objective (score only) feedback from a male (vs. female) authority figure in math reported greater confidence; belonging; self-efficacy; more favorable Science, Technology, Engineering, and Mathematics (STEM) attitudes/identification/interest; and greater implicit identification with math. Men were affected only by the type of math feedback they received, not by the source of feedback. A meta-analysis across studies confirmed results. Together, these findings suggest that positive feedback from gatekeepers is an important situational cue that can improve the outcomes of negatively stereotyped groups.
DEFINING AND NEGOTIATING THE SOCIAL VALUE OF RESEARCH IN PUBLIC HEALTH FACILITIES: PERCEPTIONS OF STAKEHOLDERS IN A RESEARCH-ACTIVE PROVINCE OF SOUTH AFRICA

PubMed Central

Lutge, Elizabeth; Slack, Catherine; Wassenaar, Douglas

2016-01-01

This paper reports on qualitative research conducted in KwaZulu-Natal, South Africa, among researchers and gate-keepers of health facilities in the province. Results suggest disparate but not irreconcilable perceptions of the social value of research in provincial health facilities. This study found that researchers tended to emphasise the contribution of research to the generation of knowledge and to the health of future patients while gate-keepers of health facilities tended to emphasise its contribution to the healthcare system and to current patients. Furthermore, relations between research stakeholders were perceived to be somewhat fragile, making it difficult for stakeholders to achieve consensus about the social value of research, as well as on ways to maximise value. Interventions to negotiate a shared perspective on the social value of research would appear to be warranted, and the findings of this study suggest some focus areas for such intervention. PMID:28060430
Efficient kinetic Monte Carlo method for reaction-diffusion problems with spatially varying annihilation rates

NASA Astrophysics Data System (ADS)

Schwarz, Karsten; Rieger, Heiko

2013-03-01

We present an efficient Monte Carlo method to simulate reaction-diffusion processes with spatially varying particle annihilation or transformation rates as it occurs for instance in the context of motor-driven intracellular transport. Like Green's function reaction dynamics and first-passage time methods, our algorithm avoids small diffusive hops by propagating sufficiently distant particles in large hops to the boundaries of protective domains. Since for spatially varying annihilation or transformation rates the single particle diffusion propagator is not known analytically, we present an algorithm that generates efficiently either particle displacements or annihilations with the correct statistics, as we prove rigorously. The numerical efficiency of the algorithm is demonstrated with an illustrative example.
Efficient sequential and parallel algorithms for finding edit distance based motifs.

PubMed

Pal, Soumitra; Xiao, Peng; Rajasekaran, Sanguthevar

2016-08-18

Motif search is an important step in extracting meaningful patterns from biological data. The general problem of motif search is intractable and there is a pressing need to develop efficient, exact and approximation algorithms to solve this problem. In this paper, we present several novel, exact, sequential and parallel algorithms for solving the (l,d) Edit-distance-based Motif Search (EMS) problem: given two integers l,d and n biological strings, find all strings of length l that appear in each input string with atmost d errors of types substitution, insertion and deletion. One popular technique to solve the problem is to explore for each input string the set of all possible l-mers that belong to the d-neighborhood of any substring of the input string and output those which are common for all input strings. We introduce a novel and provably efficient neighborhood exploration technique. We show that it is enough to consider the candidates in neighborhood which are at a distance exactly d. We compactly represent these candidate motifs using wildcard characters and efficiently explore them with very few repetitions. Our sequential algorithm uses a trie based data structure to efficiently store and sort the candidate motifs. Our parallel algorithm in a multi-core shared memory setting uses arrays for storing and a novel modification of radix-sort for sorting the candidate motifs. The algorithms for EMS are customarily evaluated on several challenging instances such as (8,1), (12,2), (16,3), (20,4), and so on. The best previously known algorithm, EMS1, is sequential and in estimated 3 days solves up to instance (16,3). Our sequential algorithms are more than 20 times faster on (16,3). On other hard instances such as (9,2), (11,3), (13,4), our algorithms are much faster. Our parallel algorithm has more than 600 % scaling performance while using 16 threads. Our algorithms have pushed up the state-of-the-art of EMS solvers and we believe that the techniques introduced in this paper are also applicable to other motif search problems such as Planted Motif Search (PMS) and Simple Motif Search (SMS).
Reconstructing householder vectors from Tall-Skinny QR

DOE PAGES

Ballard, Grey Malone; Demmel, James; Grigori, Laura; ...

2015-08-05

The Tall-Skinny QR (TSQR) algorithm is more communication efficient than the standard Householder algorithm for QR decomposition of matrices with many more rows than columns. However, TSQR produces a different representation of the orthogonal factor and therefore requires more software development to support the new representation. Further, implicitly applying the orthogonal factor to the trailing matrix in the context of factoring a square matrix is more complicated and costly than with the Householder representation. We show how to perform TSQR and then reconstruct the Householder vector representation with the same asymptotic communication efficiency and little extra computational cost. We demonstratemore » the high performance and numerical stability of this algorithm both theoretically and empirically. The new Householder reconstruction algorithm allows us to design more efficient parallel QR algorithms, with significantly lower latency cost compared to Householder QR and lower bandwidth and latency costs compared with Communication-Avoiding QR (CAQR) algorithm. Experiments on supercomputers demonstrate the benefits of the communication cost improvements: in particular, our experiments show substantial improvements over tuned library implementations for tall-and-skinny matrices. Furthermore, we also provide algorithmic improvements to the Householder QR and CAQR algorithms, and we investigate several alternatives to the Householder reconstruction algorithm that sacrifice guarantees on numerical stability in some cases in order to obtain higher performance.« less
Efficient Craig Interpolation for Linear Diophantine (Dis)Equations and Linear Modular Equations

DTIC Science & Technology

2008-02-01

Craig interpolants has enabled the development of powerful hardware and software model checking techniques. Efficient algorithms are known for computing...interpolants in rational and real linear arithmetic. We focus on subsets of integer linear arithmetic. Our main results are polynomial time algorithms ...congruences), and linear diophantine disequations. We show the utility of the proposed interpolation algorithms for discovering modular/divisibility predicates
Clustering algorithm evaluation and the development of a replacement for procedure 1. [for crop inventories

NASA Technical Reports Server (NTRS)

Lennington, R. K.; Johnson, J. K.

1979-01-01

An efficient procedure which clusters data using a completely unsupervised clustering algorithm and then uses labeled pixels to label the resulting clusters or perform a stratified estimate using the clusters as strata is developed. Three clustering algorithms, CLASSY, AMOEBA, and ISOCLS, are compared for efficiency. Three stratified estimation schemes and three labeling schemes are also considered and compared.
Parallel CE/SE Computations via Domain Decomposition

NASA Technical Reports Server (NTRS)

Himansu, Ananda; Jorgenson, Philip C. E.; Wang, Xiao-Yen; Chang, Sin-Chung

2000-01-01

This paper describes the parallelization strategy and achieved parallel efficiency of an explicit time-marching algorithm for solving conservation laws. The Space-Time Conservation Element and Solution Element (CE/SE) algorithm for solving the 2D and 3D Euler equations is parallelized with the aid of domain decomposition. The parallel efficiency of the resultant algorithm on a Silicon Graphics Origin 2000 parallel computer is checked.
Coverage-maximization in networks under resource constraints.

PubMed

Nandi, Subrata; Brusch, Lutz; Deutsch, Andreas; Ganguly, Niloy

2010-06-01

Efficient coverage algorithms are essential for information search or dispersal in all kinds of networks. We define an extended coverage problem which accounts for constrained resources of consumed bandwidth B and time T . Our solution to the network challenge is here studied for regular grids only. Using methods from statistical mechanics, we develop a coverage algorithm with proliferating message packets and temporally modulated proliferation rate. The algorithm performs as efficiently as a single random walker but O(B(d-2)/d) times faster, resulting in significant service speed-up on a regular grid of dimension d . The algorithm is numerically compared to a class of generalized proliferating random walk strategies and on regular grids shown to perform best in terms of the product metric of speed and efficiency.
An index-based algorithm for fast on-line query processing of latent semantic analysis

PubMed Central

Li, Pohan; Wang, Wei

2017-01-01

Latent Semantic Analysis (LSA) is widely used for finding the documents whose semantic is similar to the query of keywords. Although LSA yield promising similar results, the existing LSA algorithms involve lots of unnecessary operations in similarity computation and candidate check during on-line query processing, which is expensive in terms of time cost and cannot efficiently response the query request especially when the dataset becomes large. In this paper, we study the efficiency problem of on-line query processing for LSA towards efficiently searching the similar documents to a given query. We rewrite the similarity equation of LSA combined with an intermediate value called partial similarity that is stored in a designed index called partial index. For reducing the searching space, we give an approximate form of similarity equation, and then develop an efficient algorithm for building partial index, which skips the partial similarities lower than a given threshold θ. Based on partial index, we develop an efficient algorithm called ILSA for supporting fast on-line query processing. The given query is transformed into a pseudo document vector, and the similarities between query and candidate documents are computed by accumulating the partial similarities obtained from the index nodes corresponds to non-zero entries in the pseudo document vector. Compared to the LSA algorithm, ILSA reduces the time cost of on-line query processing by pruning the candidate documents that are not promising and skipping the operations that make little contribution to similarity scores. Extensive experiments through comparison with LSA have been done, which demonstrate the efficiency and effectiveness of our proposed algorithm. PMID:28520747
An index-based algorithm for fast on-line query processing of latent semantic analysis.

PubMed

Zhang, Mingxi; Li, Pohan; Wang, Wei

2017-01-01

Latent Semantic Analysis (LSA) is widely used for finding the documents whose semantic is similar to the query of keywords. Although LSA yield promising similar results, the existing LSA algorithms involve lots of unnecessary operations in similarity computation and candidate check during on-line query processing, which is expensive in terms of time cost and cannot efficiently response the query request especially when the dataset becomes large. In this paper, we study the efficiency problem of on-line query processing for LSA towards efficiently searching the similar documents to a given query. We rewrite the similarity equation of LSA combined with an intermediate value called partial similarity that is stored in a designed index called partial index. For reducing the searching space, we give an approximate form of similarity equation, and then develop an efficient algorithm for building partial index, which skips the partial similarities lower than a given threshold θ. Based on partial index, we develop an efficient algorithm called ILSA for supporting fast on-line query processing. The given query is transformed into a pseudo document vector, and the similarities between query and candidate documents are computed by accumulating the partial similarities obtained from the index nodes corresponds to non-zero entries in the pseudo document vector. Compared to the LSA algorithm, ILSA reduces the time cost of on-line query processing by pruning the candidate documents that are not promising and skipping the operations that make little contribution to similarity scores. Extensive experiments through comparison with LSA have been done, which demonstrate the efficiency and effectiveness of our proposed algorithm.
Efficient irregular wavefront propagation algorithms on Intel® Xeon Phi™

PubMed Central

Gomes, Jeremias M.; Teodoro, George; de Melo, Alba; Kong, Jun; Kurc, Tahsin; Saltz, Joel H.

2016-01-01

We investigate the execution of the Irregular Wavefront Propagation Pattern (IWPP), a fundamental computing structure used in several image analysis operations, on the Intel® Xeon Phi™ co-processor. An efficient implementation of IWPP on the Xeon Phi is a challenging problem because of IWPP’s irregularity and the use of atomic instructions in the original IWPP algorithm to resolve race conditions. On the Xeon Phi, the use of SIMD and vectorization instructions is critical to attain high performance. However, SIMD atomic instructions are not supported. Therefore, we propose a new IWPP algorithm that can take advantage of the supported SIMD instruction set. We also evaluate an alternate storage container (priority queue) to track active elements in the wavefront in an effort to improve the parallel algorithm efficiency. The new IWPP algorithm is evaluated with Morphological Reconstruction and Imfill operations as use cases. Our results show performance improvements of up to 5.63× on top of the original IWPP due to vectorization. Moreover, the new IWPP achieves speedups of 45.7× and 1.62×, respectively, as compared to efficient CPU and GPU implementations. PMID:27298591
Efficient irregular wavefront propagation algorithms on Intel® Xeon Phi™.

PubMed

Gomes, Jeremias M; Teodoro, George; de Melo, Alba; Kong, Jun; Kurc, Tahsin; Saltz, Joel H

2015-10-01

We investigate the execution of the Irregular Wavefront Propagation Pattern (IWPP), a fundamental computing structure used in several image analysis operations, on the Intel ® Xeon Phi ™ co-processor. An efficient implementation of IWPP on the Xeon Phi is a challenging problem because of IWPP's irregularity and the use of atomic instructions in the original IWPP algorithm to resolve race conditions. On the Xeon Phi, the use of SIMD and vectorization instructions is critical to attain high performance. However, SIMD atomic instructions are not supported. Therefore, we propose a new IWPP algorithm that can take advantage of the supported SIMD instruction set. We also evaluate an alternate storage container (priority queue) to track active elements in the wavefront in an effort to improve the parallel algorithm efficiency. The new IWPP algorithm is evaluated with Morphological Reconstruction and Imfill operations as use cases. Our results show performance improvements of up to 5.63 × on top of the original IWPP due to vectorization. Moreover, the new IWPP achieves speedups of 45.7 × and 1.62 × , respectively, as compared to efficient CPU and GPU implementations.
Prediction and Reduction of the Aggregation of Monoclonal Antibodies.

PubMed

van der Kant, Rob; Karow-Zwick, Anne R; Van Durme, Joost; Blech, Michaela; Gallardo, Rodrigo; Seeliger, Daniel; Aßfalg, Kerstin; Baatsen, Pieter; Compernolle, Griet; Gils, Ann; Studts, Joey M; Schulz, Patrick; Garidel, Patrick; Schymkowitz, Joost; Rousseau, Frederic

2017-04-21

Protein aggregation remains a major area of focus in the production of monoclonal antibodies. Improving the intrinsic properties of antibodies can improve manufacturability, attrition rates, safety, formulation, titers, immunogenicity, and solubility. Here, we explore the potential of predicting and reducing the aggregation propensity of monoclonal antibodies, based on the identification of aggregation-prone regions and their contribution to the thermodynamic stability of the protein. Although aggregation-prone regions are thought to occur in the antigen binding region to drive hydrophobic binding with antigen, we were able to rationally design variants that display a marked decrease in aggregation propensity while retaining antigen binding through the introduction of artificial aggregation gatekeeper residues. The reduction in aggregation propensity was accompanied by an increase in expression titer, showing that reducing protein aggregation is beneficial throughout the development process. The data presented show that this approach can significantly reduce liabilities in novel therapeutic antibodies and proteins, leading to a more efficient path to clinical studies. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.
Gatekeepers as Care Providers: The Care Work of Patient-centered Medical Home Clerical Staff.

PubMed

Solimeo, Samantha L; Ono, Sarah S; Stewart, Kenda R; Lampman, Michelle A; Rosenthal, Gary E; Stewart, Greg L

2017-03-01

International implementation of the patient-centered medical home (PCMH) model for delivering primary care has dramatically increased in the last decade. A majority of research on PCMH's impact has emphasized the care provided by clinically trained staff. In this article, we report our ethnographic analysis of data collected from Department of Veterans Affairs staff implementing PACT, the VA version of PCMH. Teams were trained to use within-team delegation, largely accomplished through attention to clinical licensure, to differentiate staff in providing efficient, patient-centered care. In doing so, PACT may reinforce a clinically defined culture of care that countermands PCMH ideals. Such competing rubrics for care are brought into relief through a focus on the care work performed by clerks. Ethnographic analysis identifies clerks' care as a kind of emotional dirty work, signaling important areas for future anthropological study of the relationships among patient-centered care, stigma, and clinical authority. © 2016 by the American Anthropological Association.
Thinking outside the box - novel antibacterials to tackle the resistance crisis.

PubMed

Lakemeyer, Markus; Zhao, Weining; Mandl, Franziska A; Hammann, Peter; Sieber, Stephan Axel

2018-06-25

The public view on antibiotics as reliable medicine has changed when reports about "resistant superbugs" shattered the news. While reasons for this development are easily spotted, solutions for re-establishing effective antibiotics are still in their infancy. This review encompasses several aspects of the antibiotic development pipeline from very early strategies to mature drugs. We provide an interdisciplinary overview of methods suitable for mining novel antibiotics and discuss strategies to unravel their modes of action. Select examples of antibiotics recently identified using these platforms not only illustrate the efficiency of these measures, but also highlight promising clinical candidates with therapeutic potential. Furthermore, the concept of molecules that disarm pathogens by addressing gatekeepers of virulence will be covered. We conclude with an evaluation of antibacterials currently in clinical development. Overall, this review aims to connect select innovative antimicrobial approaches to stimulate interdisciplinary partnerships between chemists from academia and industry. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Epigenetic restriction of embryonic cell lineage fate by methylation of Elf5

PubMed Central

Ng, Ray Kit; Dean, Wendy; Dawson, Claire; Lucifero, Diana; Madeja, Zofia; Reik, Wolf; Hemberger, Myriam

2008-01-01

Mouse ES cells can differentiate into all three germ layers of the embryo but are generally excluded from the trophoblast lineage. Here we show that ES cells deficient in DNA methylation can differentiate efficiently into trophoblast derivatives. In a genome-wide screen we identify the transcription factor Elf5 as methylated and repressed in ES cells, and hypomethylated and expressed in TS and methylation-deficient ES cells. Elf5 creates a positive feedback loop with TS cell determinants Cdx2 and Eomes that is restricted to the trophoblast lineage by epigenetic regulation of Elf5. Importantly, the late-acting function of Elf5 allows initial plasticity and regulation in the early blastocyst. Thus, Elf5 acts downstream of initial lineage determination as a gatekeeper to reinforce commitment to the trophoblast lineage, or to abort this pathway in epiblast cells. This epigenetic restriction of cell lineage fate provides a molecular mechanism for Waddington’s concept of canalization of developmental pathways. PMID:18836439

Efficient, Decentralized Detection of Qualitative Spatial Events in a Dynamic Scalar Field

PubMed Central

Jeong, Myeong-Hun; Duckham, Matt

2015-01-01

This paper describes an efficient, decentralized algorithm to monitor qualitative spatial events in a dynamic scalar field. The events of interest involve changes to the critical points (i.e., peak, pits and passes) and edges of the surface network derived from the field. Four fundamental types of event (appearance, disappearance, movement and switch) are defined. Our algorithm is designed to rely purely on qualitative information about the neighborhoods of nodes in the sensor network and does not require information about nodes’ coordinate positions. Experimental investigations confirm that our algorithm is efficient, with O(n) overall communication complexity (where n is the number of nodes in the sensor network), an even load balance and low operational latency. The accuracy of event detection is comparable to established centralized algorithms for the identification of critical points of a surface network. Our algorithm is relevant to a broad range of environmental monitoring applications of sensor networks. PMID:26343672
Seeding the initial population with feasible solutions in metaheuristic optimization of steel trusses

NASA Astrophysics Data System (ADS)

Kazemzadeh Azad, Saeid

2018-01-01

In spite of considerable research work on the development of efficient algorithms for discrete sizing optimization of steel truss structures, only a few studies have addressed non-algorithmic issues affecting the general performance of algorithms. For instance, an important question is whether starting the design optimization from a feasible solution is fruitful or not. This study is an attempt to investigate the effect of seeding the initial population with feasible solutions on the general performance of metaheuristic techniques. To this end, the sensitivity of recently proposed metaheuristic algorithms to the feasibility of initial candidate designs is evaluated through practical discrete sizing of real-size steel truss structures. The numerical experiments indicate that seeding the initial population with feasible solutions can improve the computational efficiency of metaheuristic structural optimization algorithms, especially in the early stages of the optimization. This paves the way for efficient metaheuristic optimization of large-scale structural systems.
Advanced time integration algorithms for dislocation dynamics simulations of work hardening

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

Sills, Ryan B.; Aghaei, Amin; Cai, Wei

Efficient time integration is a necessity for dislocation dynamics simulations of work hardening to achieve experimentally relevant strains. In this work, an efficient time integration scheme using a high order explicit method with time step subcycling and a newly-developed collision detection algorithm are evaluated. First, time integrator performance is examined for an annihilating Frank–Read source, showing the effects of dislocation line collision. The integrator with subcycling is found to significantly out-perform other integration schemes. The performance of the time integration and collision detection algorithms is then tested in a work hardening simulation. The new algorithms show a 100-fold speed-up relativemore » to traditional schemes. As a result, subcycling is shown to improve efficiency significantly while maintaining an accurate solution, and the new collision algorithm allows an arbitrarily large time step size without missing collisions.« less
Advanced time integration algorithms for dislocation dynamics simulations of work hardening

DOE PAGES

Sills, Ryan B.; Aghaei, Amin; Cai, Wei

2016-04-25

Efficient time integration is a necessity for dislocation dynamics simulations of work hardening to achieve experimentally relevant strains. In this work, an efficient time integration scheme using a high order explicit method with time step subcycling and a newly-developed collision detection algorithm are evaluated. First, time integrator performance is examined for an annihilating Frank–Read source, showing the effects of dislocation line collision. The integrator with subcycling is found to significantly out-perform other integration schemes. The performance of the time integration and collision detection algorithms is then tested in a work hardening simulation. The new algorithms show a 100-fold speed-up relativemore » to traditional schemes. As a result, subcycling is shown to improve efficiency significantly while maintaining an accurate solution, and the new collision algorithm allows an arbitrarily large time step size without missing collisions.« less
Efficient, Decentralized Detection of Qualitative Spatial Events in a Dynamic Scalar Field.

PubMed

Jeong, Myeong-Hun; Duckham, Matt

2015-08-28

This paper describes an efficient, decentralized algorithm to monitor qualitative spatial events in a dynamic scalar field. The events of interest involve changes to the critical points (i.e., peak, pits and passes) and edges of the surface network derived from the field. Four fundamental types of event (appearance, disappearance, movement and switch) are defined. Our algorithm is designed to rely purely on qualitative information about the neighborhoods of nodes in the sensor network and does not require information about nodes' coordinate positions. Experimental investigations confirm that our algorithm is efficient, with O(n) overall communication complexity (where n is the number of nodes in the sensor network), an even load balance and low operational latency. The accuracy of event detection is comparable to established centralized algorithms for the identification of critical points of a surface network. Our algorithm is relevant to a broad range of environmental monitoring applications of sensor networks.
Efficient Boundary Extraction of BSP Solids Based on Clipping Operations.

PubMed

Wang, Charlie C L; Manocha, Dinesh

2013-01-01

We present an efficient algorithm to extract the manifold surface that approximates the boundary of a solid represented by a Binary Space Partition (BSP) tree. Our polygonization algorithm repeatedly performs clipping operations on volumetric cells that correspond to a spatial convex partition and computes the boundary by traversing the connected cells. We use point-based representations along with finite-precision arithmetic to improve the efficiency and generate the B-rep approximation of a BSP solid. The core of our polygonization method is a novel clipping algorithm that uses a set of logical operations to make it resistant to degeneracies resulting from limited precision of floating-point arithmetic. The overall BSP to B-rep conversion algorithm can accurately generate boundaries with sharp and small features, and is faster than prior methods. At the end of this paper, we use this algorithm for a few geometric processing applications including Boolean operations, model repair, and mesh reconstruction.
A comparison of select image-compression algorithms for an electronic still camera

NASA Technical Reports Server (NTRS)

Nerheim, Rosalee

1989-01-01

This effort is a study of image-compression algorithms for an electronic still camera. An electronic still camera can record and transmit high-quality images without the use of film, because images are stored digitally in computer memory. However, high-resolution images contain an enormous amount of information, and will strain the camera's data-storage system. Image compression will allow more images to be stored in the camera's memory. For the electronic still camera, a compression algorithm that produces a reconstructed image of high fidelity is most important. Efficiency of the algorithm is the second priority. High fidelity and efficiency are more important than a high compression ratio. Several algorithms were chosen for this study and judged on fidelity, efficiency and compression ratio. The transform method appears to be the best choice. At present, the method is compressing images to a ratio of 5.3:1 and producing high-fidelity reconstructed images.
A fast and accurate frequency estimation algorithm for sinusoidal signal with harmonic components

NASA Astrophysics Data System (ADS)

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

2016-10-01

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

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

Curtis, J.H.; Michelotti, M.D.; Riemer, N.

2016-10-01

Stochastic particle-resolved methods have proven useful for simulating multi-dimensional systems such as composition-resolved aerosol size distributions. While particle-resolved methods have substantial benefits for highly detailed simulations, these techniques suffer from high computational cost, motivating efforts to improve their algorithmic efficiency. Here we formulate an algorithm for accelerating particle removal processes by aggregating particles of similar size into bins. We present the Binned Algorithm for particle removal processes and analyze its performance with application to the atmospherically relevant process of aerosol dry deposition. We show that the Binned Algorithm can dramatically improve the efficiency of particle removals, particularly for low removalmore » rates, and that computational cost is reduced without introducing additional error. In simulations of aerosol particle removal by dry deposition in atmospherically relevant conditions, we demonstrate about 50-times increase in algorithm efficiency.« less
Compression of multispectral Landsat imagery using the Embedded Zerotree Wavelet (EZW) algorithm

NASA Technical Reports Server (NTRS)

Shapiro, Jerome M.; Martucci, Stephen A.; Czigler, Martin

1994-01-01

The Embedded Zerotree Wavelet (EZW) algorithm has proven to be an extremely efficient and flexible compression algorithm for low bit rate image coding. The embedding algorithm attempts to order the bits in the bit stream in numerical importance and thus a given code contains all lower rate encodings of the same algorithm. Therefore, precise bit rate control is achievable and a target rate or distortion metric can be met exactly. Furthermore, the technique is fully image adaptive. An algorithm for multispectral image compression which combines the spectral redundancy removal properties of the image-dependent Karhunen-Loeve Transform (KLT) with the efficiency, controllability, and adaptivity of the embedded zerotree wavelet algorithm is presented. Results are shown which illustrate the advantage of jointly encoding spectral components using the KLT and EZW.
Efficient model learning methods for actor-critic control.

PubMed

Grondman, Ivo; Vaandrager, Maarten; Buşoniu, Lucian; Babuska, Robert; Schuitema, Erik

2012-06-01

We propose two new actor-critic algorithms for reinforcement learning. Both algorithms use local linear regression (LLR) to learn approximations of the functions involved. A crucial feature of the algorithms is that they also learn a process model, and this, in combination with LLR, provides an efficient policy update for faster learning. The first algorithm uses a novel model-based update rule for the actor parameters. The second algorithm does not use an explicit actor but learns a reference model which represents a desired behavior, from which desired control actions can be calculated using the inverse of the learned process model. The two novel methods and a standard actor-critic algorithm are applied to the pendulum swing-up problem, in which the novel methods achieve faster learning than the standard algorithm.
Trajectory NG: portable, compressed, general molecular dynamics trajectories.

PubMed

Spångberg, Daniel; Larsson, Daniel S D; van der Spoel, David

2011-10-01

We present general algorithms for the compression of molecular dynamics trajectories. The standard ways to store MD trajectories as text or as raw binary floating point numbers result in very large files when efficient simulation programs are used on supercomputers. Our algorithms are based on the observation that differences in atomic coordinates/velocities, in either time or space, are generally smaller than the absolute values of the coordinates/velocities. Also, it is often possible to store values at a lower precision. We apply several compression schemes to compress the resulting differences further. The most efficient algorithms developed here use a block sorting algorithm in combination with Huffman coding. Depending on the frequency of storage of frames in the trajectory, either space, time, or combinations of space and time differences are usually the most efficient. We compare the efficiency of our algorithms with each other and with other algorithms present in the literature for various systems: liquid argon, water, a virus capsid solvated in 15 mM aqueous NaCl, and solid magnesium oxide. We perform tests to determine how much precision is necessary to obtain accurate structural and dynamic properties, as well as benchmark a parallelized implementation of the algorithms. We obtain compression ratios (compared to single precision floating point) of 1:3.3-1:35 depending on the frequency of storage of frames and the system studied.
An efficient parallel termination detection algorithm

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

Baker, A. H.; Crivelli, S.; Jessup, E. R.

2004-05-27

Information local to any one processor is insufficient to monitor the overall progress of most distributed computations. Typically, a second distributed computation for detecting termination of the main computation is necessary. In order to be a useful computational tool, the termination detection routine must operate concurrently with the main computation, adding minimal overhead, and it must promptly and correctly detect termination when it occurs. In this paper, we present a new algorithm for detecting the termination of a parallel computation on distributed-memory MIMD computers that satisfies all of those criteria. A variety of termination detection algorithms have been devised. Ofmore » these, the algorithm presented by Sinha, Kale, and Ramkumar (henceforth, the SKR algorithm) is unique in its ability to adapt to the load conditions of the system on which it runs, thereby minimizing the impact of termination detection on performance. Because their algorithm also detects termination quickly, we consider it to be the most efficient practical algorithm presently available. The termination detection algorithm presented here was developed for use in the PMESC programming library for distributed-memory MIMD computers. Like the SKR algorithm, our algorithm adapts to system loads and imposes little overhead. Also like the SKR algorithm, ours is tree-based, and it does not depend on any assumptions about the physical interconnection topology of the processors or the specifics of the distributed computation. In addition, our algorithm is easier to implement and requires only half as many tree traverses as does the SKR algorithm. This paper is organized as follows. In section 2, we define our computational model. In section 3, we review the SKR algorithm. We introduce our new algorithm in section 4, and prove its correctness in section 5. We discuss its efficiency and present experimental results in section 6.« less
An Object-Oriented Collection of Minimum Degree Algorithms: Design, Implementation, and Experiences

NASA Technical Reports Server (NTRS)

Kumfert, Gary; Pothen, Alex

1999-01-01

The multiple minimum degree (MMD) algorithm and its variants have enjoyed 20+ years of research and progress in generating fill-reducing orderings for sparse, symmetric positive definite matrices. Although conceptually simple, efficient implementations of these algorithms are deceptively complex and highly specialized. In this case study, we present an object-oriented library that implements several recent minimum degree-like algorithms. We discuss how object-oriented design forces us to decompose these algorithms in a different manner than earlier codes and demonstrate how this impacts the flexibility and efficiency of our C++ implementation. We compare the performance of our code against other implementations in C or Fortran.
Sparse RNA folding revisited: space-efficient minimum free energy structure prediction.

PubMed

Will, Sebastian; Jabbari, Hosna

2016-01-01

RNA secondary structure prediction by energy minimization is the central computational tool for the analysis of structural non-coding RNAs and their interactions. Sparsification has been successfully applied to improve the time efficiency of various structure prediction algorithms while guaranteeing the same result; however, for many such folding problems, space efficiency is of even greater concern, particularly for long RNA sequences. So far, space-efficient sparsified RNA folding with fold reconstruction was solved only for simple base-pair-based pseudo-energy models. Here, we revisit the problem of space-efficient free energy minimization. Whereas the space-efficient minimization of the free energy has been sketched before, the reconstruction of the optimum structure has not even been discussed. We show that this reconstruction is not possible in trivial extension of the method for simple energy models. Then, we present the time- and space-efficient sparsified free energy minimization algorithm SparseMFEFold that guarantees MFE structure prediction. In particular, this novel algorithm provides efficient fold reconstruction based on dynamically garbage-collected trace arrows. The complexity of our algorithm depends on two parameters, the number of candidates Z and the number of trace arrows T; both are bounded by [Formula: see text], but are typically much smaller. The time complexity of RNA folding is reduced from [Formula: see text] to [Formula: see text]; the space complexity, from [Formula: see text] to [Formula: see text]. Our empirical results show more than 80 % space savings over RNAfold [Vienna RNA package] on the long RNAs from the RNA STRAND database (≥2500 bases). The presented technique is intentionally generalizable to complex prediction algorithms; due to their high space demands, algorithms like pseudoknot prediction and RNA-RNA-interaction prediction are expected to profit even stronger than "standard" MFE folding. SparseMFEFold is free software, available at http://www.bioinf.uni-leipzig.de/~will/Software/SparseMFEFold.
An efficient and robust algorithm for two dimensional time dependent incompressible Navier-Stokes equations: High Reynolds number flows

NASA Technical Reports Server (NTRS)

Goodrich, John W.

1991-01-01

An algorithm is presented for unsteady two-dimensional incompressible Navier-Stokes calculations. This algorithm is based on the fourth order partial differential equation for incompressible fluid flow which uses the streamfunction as the only dependent variable. The algorithm is second order accurate in both time and space. It uses a multigrid solver at each time step. It is extremely efficient with respect to the use of both CPU time and physical memory. It is extremely robust with respect to Reynolds number.
Optimized atom position and coefficient coding for matching pursuit-based image compression.

PubMed

Shoa, Alireza; Shirani, Shahram

2009-12-01

In this paper, we propose a new encoding algorithm for matching pursuit image coding. We show that coding performance is improved when correlations between atom positions and atom coefficients are both used in encoding. We find the optimum tradeoff between efficient atom position coding and efficient atom coefficient coding and optimize the encoder parameters. Our proposed algorithm outperforms the existing coding algorithms designed for matching pursuit image coding. Additionally, we show that our algorithm results in better rate distortion performance than JPEG 2000 at low bit rates.
Queue and stack sorting algorithm optimization and performance analysis

NASA Astrophysics Data System (ADS)

Qian, Mingzhu; Wang, Xiaobao

2018-04-01

Sorting algorithm is one of the basic operation of a variety of software development, in data structures course specializes in all kinds of sort algorithm. The performance of the sorting algorithm is directly related to the efficiency of the software. A lot of excellent scientific research queue is constantly optimizing algorithm, algorithm efficiency better as far as possible, the author here further research queue combined with stacks of sorting algorithms, the algorithm is mainly used for alternating operation queue and stack storage properties, Thus avoiding the need for a large number of exchange or mobile operations in the traditional sort. Before the existing basis to continue research, improvement and optimization, the focus on the optimization of the time complexity of the proposed optimization and improvement, The experimental results show that the improved effectively, at the same time and the time complexity and space complexity of the algorithm, the stability study corresponding research. The improvement and optimization algorithm, improves the practicability.
Bridging Education and Practice with a Competency-Based Learning Contract

ERIC Educational Resources Information Center

Molina, Veronica; Molina-Moore, Tammy; Smith, Misty G.; Pratt, Francine E.

2018-01-01

Field work programs have a substantial responsibility for providing support and gatekeeping functions while ensuring an educational experience that allows students to master the nine holistic, multidimensional social work accreditation competencies. With additional emphasis on field as a "signature pedagogy," field directors are tasked…
Targeting Summer Credit Recovery

ERIC Educational Resources Information Center

Eno, Jared; Heppen, Jessica

2014-01-01

Algebra is considered a key gatekeeper for higher-level mathematics course-taking in high school and for college enrollment (Adelman, 2006; Gamoran & Hannigan, 2000). Yet, algebra pass rates are consistently low in many places (Higgins, 2008; Ham & Walker, 1999; Helfand, 2006), including Chicago Public Schools (CPS). This is of particular…

"Ward v. Wilbanks": Counselor Educators Respond

ERIC Educational Resources Information Center

Burkholder, David; Hall, Stephanie F.; Burkholder, Jessica

2014-01-01

This article investigated 71 counselor educators' perspectives and pedagogical practices related to "Ward v. Wilbanks" (2009) and the American Counseling Association (ACA) response to the case. The authors used qualitative content analysis to identify 6 themes from survey data: (a) views on gatekeeping and student training; (b)…
Focus on Fractions to Scaffold Algebra

ERIC Educational Resources Information Center

Ooten, Cheryl Thomas

2013-01-01

Beginning algebra is a gatekeeper course into the pipeline to higher mathematics courses required for respected professions in engineering, science, statistics, mathematics, education, and technology. Beginning algebra can also be a perfect storm if the necessary foundational skills are not within a student's grasp. What skills ensure beginning…
Interprofessional Collaboration between General Physicians and Emergency Department Teams in Belgium: A Qualitative Study

PubMed Central

Tricas-Sauras, Sandra; Darras, Elisabeth; Macq, Jean

2017-01-01

This study aimed to assess interprofessional collaboration between general physicians and emergency departments in the French speaking regions of Belgium. Eight group interviews were conducted both in rural and urban areas, including in Brussels. Findings showed that the relational components of collaboration, which are highly valued by individuals involved, comprise mutual acquaintanceship and trust, shared power and objectives. The organizational components of collaboration included out-of-hours services, role clarification, leadership and overall environment. Communication and patient’s role were also found to be key elements in enhancing or hindering collaboration across these two levels of care. Relationships between general physicians and emergency departments’ teams were tightly linked to organizational factors and the general macro-environment. Health system regulation did not appear to play a significant role in promoting collaboration between actors. A better role clarification is needed in order to foster multidisciplinary team coordination for a more efficient patient management. Finally, economic power and private practice impeded interprofessional collaboration between the care teams. In conclusion, many challenges need to be addressed for achievement of a better collaboration and more efficient integration. Not only should integration policies aim at reinforcing the role of general physicians as gatekeepers, also they should target patients’ awareness and empowerment. PMID:29588632
Electron efficiency measurements with the ATLAS detector using 2012 LHC proton–proton collision data

DOE PAGES

Aaboud, M.; Aad, G.; Abbott, B.; ...

2017-03-27

This paper describes the algorithms for the reconstruction and identification of electrons in the central region of the ATLAS detector at the Large Hadron Collider (LHC). These algorithms were used for all ATLAS results with electrons in the final state that are based on the 2012 pp collision data produced by the LHC at s = 8 TeV. The efficiency of these algorithms, together with the charge misidentification rate, is measured in data and evaluated in simulated samples using electrons from Z→ ee, Z→ eeγ and J/ ψ→ ee decays. For these efficiency measurements, the full recorded data set, corresponding tomore » an integrated luminosity of 20.3 fb - 1 , is used. Based on a new reconstruction algorithm used in 2012, the electron reconstruction efficiency is 97% for electrons with E T = 15 GeV and 99% at E T = 50 GeV. Combining this with the efficiency of additional selection criteria to reject electrons from background processes or misidentified hadrons, the efficiency to reconstruct and identify electrons at the ATLAS experiment varies from 65 to 95%, depending on the transverse momentum of the electron and background rejection.« less
Electron efficiency measurements with the ATLAS detector using 2012 LHC proton-proton collision data.

PubMed

Aaboud, M; Aad, G; Abbott, B; Abdallah, J; Abdinov, O; Abeloos, B; AbouZeid, O S; Abraham, N L; Abramowicz, H; Abreu, H; Abreu, R; Abulaiti, Y; Acharya, B S; Adachi, S; Adamczyk, L; Adams, D L; Adelman, J; Adomeit, S; Adye, T; Affolder, A A; Agatonovic-Jovin, T; Aguilar-Saavedra, J A; Ahlen, S P; Ahmadov, F; Aielli, G; Akerstedt, H; Åkesson, T P A; Akimov, A V; Alberghi, G L; Albert, J; Albrand, S; Alconada Verzini, M J; Aleksa, M; Aleksandrov, I N; Alexa, C; Alexander, G; Alexopoulos, T; Alhroob, M; Ali, B; Aliev, M; Alimonti, G; Alison, J; Alkire, S P; Allbrooke, B M M; Allen, B W; Allport, P P; Aloisio, A; Alonso, A; Alonso, F; Alpigiani, C; Alshehri, A A; Alstaty, M; Alvarez Gonzalez, B; Álvarez Piqueras, D; Alviggi, M G; Amadio, B T; Amaral Coutinho, Y; Amelung, C; Amidei, D; Amor Dos Santos, S P; Amorim, A; Amoroso, S; Amundsen, G; Anastopoulos, C; Ancu, L S; Andari, N; Andeen, T; Anders, C F; Anders, J K; Anderson, K J; Andreazza, A; Andrei, V; Angelidakis, S; Angelozzi, I; Angerami, A; Anghinolfi, F; Anisenkov, A V; Anjos, N; Annovi, A; Antel, C; Antonelli, M; Antonov, A; Antrim, D J; Anulli, F; Aoki, M; Aperio Bella, L; Arabidze, G; Arai, Y; Araque, J P; Arce, A T H; Arduh, F A; Arguin, J-F; Argyropoulos, S; Arik, M; Armbruster, A J; Armitage, L J; Arnaez, O; Arnold, H; Arratia, M; Arslan, O; Artamonov, A; Artoni, G; Artz, S; Asai, S; Asbah, N; Ashkenazi, A; Åsman, B; Asquith, L; Assamagan, K; Astalos, R; Atkinson, M; Atlay, N B; Augsten, K; Avolio, G; Axen, B; Ayoub, M K; Azuelos, G; Baak, M A; Baas, A E; Baca, M J; Bachacou, H; Bachas, K; Backes, M; Backhaus, M; Bagiacchi, P; Bagnaia, P; Bai, Y; Baines, J T; Bajic, M; Baker, O K; Baldin, E M; Balek, P; Balestri, T; Balli, F; Balunas, W K; Banas, E; Banerjee, Sw; Bannoura, A A E; Barak, L; Barberio, E L; Barberis, D; Barbero, M; Barillari, T; Barisits, M-S; Barklow, T; Barlow, N; Barnes, S L; Barnett, B M; Barnett, R M; Barnovska-Blenessy, Z; Baroncelli, A; Barone, G; Barr, A J; Barranco Navarro, L; Barreiro, F; da Costa, J Barreiro Guimarães; Bartoldus, R; Barton, A E; Bartos, P; Basalaev, A; Bassalat, A; Bates, R L; Batista, S J; Batley, J R; Battaglia, M; Bauce, M; Bauer, F; Bawa, H S; Beacham, J B; Beattie, M D; Beau, T; Beauchemin, P H; Bechtle, P; Beck, H P; Becker, K; Becker, M; Beckingham, M; Becot, C; Beddall, A J; Beddall, A; Bednyakov, V A; Bedognetti, M; Bee, C P; Beemster, L J; Beermann, T A; Begel, M; Behr, J K; Bell, A S; Bella, G; Bellagamba, L; Bellerive, A; Bellomo, M; Belotskiy, K; Beltramello, O; Belyaev, N L; Benary, O; Benchekroun, D; Bender, M; Bendtz, K; Benekos, N; Benhammou, Y; Benhar Noccioli, E; Benitez, J; Benjamin, D P; Bensinger, J R; Bentvelsen, S; Beresford, L; Beretta, M; Berge, D; Bergeaas Kuutmann, E; Berger, N; Beringer, J; Berlendis, S; Bernard, N R; Bernius, C; Bernlochner, F U; Berry, T; Berta, P; Bertella, C; Bertoli, G; Bertolucci, F; Bertram, I A; Bertsche, C; Bertsche, D; Besjes, G J; Bessidskaia Bylund, O; Bessner, M; Besson, N; Betancourt, C; Bethani, A; Bethke, S; Bevan, A J; Bianchi, R M; Bianco, M; Biebel, O; Biedermann, D; Bielski, R; Biesuz, N V; Biglietti, M; De Mendizabal, J Bilbao; Billoud, T R V; Bilokon, H; Bindi, M; Bingul, A; Bini, C; Biondi, S; Bisanz, T; Bjergaard, D M; Black, C W; Black, J E; Black, K M; Blackburn, D; Blair, R E; Blazek, T; Bloch, I; Blocker, C; Blue, A; Blum, W; Blumenschein, U; Blunier, S; Bobbink, G J; Bobrovnikov, V S; Bocchetta, S S; Bocci, A; Bock, C; Boehler, M; Boerner, D; Bogaerts, J A; Bogavac, D; Bogdanchikov, A G; Bohm, C; Boisvert, V; Bokan, P; Bold, T; Boldyrev, A S; Bomben, M; Bona, M; Boonekamp, M; Borisov, A; Borissov, G; Bortfeldt, J; Bortoletto, D; Bortolotto, V; Bos, K; Boscherini, D; Bosman, M; Bossio Sola, J D; Boudreau, J; Bouffard, J; Bouhova-Thacker, E V; Boumediene, D; Bourdarios, C; Boutle, S K; Boveia, A; Boyd, J; Boyko, I R; Bracinik, J; Brandt, A; Brandt, G; Brandt, O; Bratzler, U; Brau, B; Brau, J E; Breaden Madden, W D; Brendlinger, K; Brennan, A J; Brenner, L; Brenner, R; Bressler, S; Bristow, T M; Britton, D; Britzger, D; Brochu, F M; Brock, I; Brock, R; Brooijmans, G; Brooks, T; Brooks, W K; Brosamer, J; Brost, E; Broughton, J H; de Renstrom, P A Bruckman; Bruncko, D; Bruneliere, R; Bruni, A; Bruni, G; Bruni, L S; Brunt, B H; Bruschi, M; Bruscino, N; Bryant, P; Bryngemark, L; Buanes, T; Buat, Q; Buchholz, P; Buckley, A G; Budagov, I A; Buehrer, F; Bugge, M K; Bulekov, O; Bullock, D; Burckhart, H; Burdin, S; Burgard, C D; Burger, A M; Burghgrave, B; Burka, K; Burke, S; Burmeister, I; Burr, J T P; Busato, E; Büscher, D; Büscher, V; Bussey, P; Butler, J M; Buttar, C M; Butterworth, J M; Butti, P; Buttinger, W; Buzatu, A; Buzykaev, A R; Cabrera Urbán, S; Caforio, D; Cairo, V M; Cakir, O; Calace, N; Calafiura, P; Calandri, A; Calderini, G; Calfayan, P; Callea, G; Caloba, L P; Calvente Lopez, S; Calvet, D; Calvet, S; Calvet, T P; Camacho Toro, R; Camarda, S; Camarri, P; Cameron, D; Caminal Armadans, R; Camincher, C; Campana, S; Campanelli, M; Camplani, A; Campoverde, A; Canale, V; Canepa, A; Cano Bret, M; Cantero, J; Cao, T; Capeans Garrido, M D M; Caprini, I; Caprini, M; Capua, M; Carbone, R M; Cardarelli, R; Cardillo, F; Carli, I; Carli, T; Carlino, G; Carlson, B T; Carminati, L; Carney, R M D; Caron, S; Carquin, E; Carrillo-Montoya, G D; Carter, J R; Carvalho, J; Casadei, D; Casado, M P; Casolino, M; Casper, D W; Castaneda-Miranda, E; Castelijn, R; Castelli, A; Castillo Gimenez, V; Castro, N F; Catinaccio, A; Catmore, J R; Cattai, A; Caudron, J; Cavaliere, V; Cavallaro, E; Cavalli, D; Cavalli-Sforza, M; Cavasinni, V; Ceradini, F; Cerda Alberich, L; Cerqueira, A S; Cerri, A; Cerrito, L; Cerutti, F; Cervelli, A; Cetin, S A; Chafaq, A; Chakraborty, D; Chan, S K; Chan, Y L; Chang, P; Chapman, J D; Charlton, D G; Chatterjee, A; Chau, C C; Chavez Barajas, C A; Che, S; Cheatham, S; Chegwidden, A; Chekanov, S; Chekulaev, S V; Chelkov, G A; Chelstowska, M A; Chen, C; Chen, H; Chen, S; Chen, S; Chen, X; Chen, Y; Cheng, H C; Cheng, H J; Cheng, Y; Cheplakov, A; Cheremushkina, E; El Moursli, R Cherkaoui; Chernyatin, V; Cheu, E; Chevalier, L; Chiarella, V; Chiarelli, G; Chiodini, G; Chisholm, A S; Chitan, A; Chizhov, M V; Choi, K; Chomont, A R; Chouridou, S; Chow, B K B; Christodoulou, V; Chromek-Burckhart, D; Chudoba, J; Chuinard, A J; Chwastowski, J J; Chytka, L; Ciapetti, G; Ciftci, A K; Cinca, D; Cindro, V; Cioara, I A; Ciocca, C; Ciocio, A; Cirotto, F; Citron, Z H; Citterio, M; Ciubancan, M; Clark, A; Clark, B L; Clark, M R; Clark, P J; Clarke, R N; Clement, C; Coadou, Y; Cobal, M; Coccaro, A; Cochran, J; Colasurdo, L; Cole, B; Colijn, A P; Collot, J; Colombo, T; Conde Muiño, P; Coniavitis, E; Connell, S H; Connelly, I A; Consorti, V; Constantinescu, S; Conti, G; Conventi, F; Cooke, M; Cooper, B D; Cooper-Sarkar, A M; Cormier, F; Cormier, K J R; Cornelissen, T; Corradi, M; Corriveau, F; Cortes-Gonzalez, A; Cortiana, G; Costa, G; Costa, M J; Costanzo, D; Cottin, G; Cowan, G; Cox, B E; Cranmer, K; Crawley, S J; Cree, G; Crépé-Renaudin, S; Crescioli, F; Cribbs, W A; Crispin Ortuzar, M; Cristinziani, M; Croft, V; Crosetti, G; Cueto, A; Cuhadar Donszelmann, T; Cummings, J; Curatolo, M; Cúth, J; Czirr, H; Czodrowski, P; D'amen, G; D'Auria, S; D'Onofrio, M; Da Cunha Sargedas De Sousa, M J; Da Via, C; Dabrowski, W; Dado, T; Dai, T; Dale, O; Dallaire, F; Dallapiccola, C; Dam, M; Dandoy, J R; Dang, N P; Daniells, A C; Dann, N S; Danninger, M; Dano Hoffmann, M; Dao, V; Darbo, G; Darmora, S; Dassoulas, J; Dattagupta, A; Davey, W; David, C; Davidek, T; Davies, M; Davison, P; Dawe, E; Dawson, I; De, K; de Asmundis, R; De Benedetti, A; De Castro, S; De Cecco, S; De Groot, N; de Jong, P; De la Torre, H; De Lorenzi, F; De Maria, A; De Pedis, D; De Salvo, A; De Sanctis, U; De Santo, A; De Vivie De Regie, J B; Dearnaley, W J; Debbe, R; Debenedetti, C; Dedovich, D V; Dehghanian, N; Deigaard, I; Del Gaudio, M; Del Peso, J; Del Prete, T; Delgove, D; Deliot, F; Delitzsch, C M; Dell'Acqua, A; Dell'Asta, L; Dell'Orso, M; Della Pietra, M; Della Volpe, D; Delmastro, M; Delsart, P A; DeMarco, D A; Demers, S; Demichev, M; Demilly, A; Denisov, S P; Denysiuk, D; Derendarz, D; Derkaoui, J E; Derue, F; Dervan, P; Desch, K; Deterre, C; Dette, K; Deviveiros, P O; Dewhurst, A; Dhaliwal, S; Di Ciaccio, A; Di Ciaccio, L; Di Clemente, W K; Di Donato, C; Di Girolamo, A; Di Girolamo, B; Di Micco, B; Di Nardo, R; Di Petrillo, K F; Di Simone, A; Di Sipio, R; Di Valentino, D; Diaconu, C; Diamond, M; Dias, F A; Diaz, M A; Diehl, E B; Dietrich, J; Díez Cornell, S; Dimitrievska, A; Dingfelder, J; Dita, P; Dita, S; Dittus, F; Djama, F; Djobava, T; Djuvsland, J I; do Vale, M A B; Dobos, D; Dobre, M; Doglioni, C; Dolejsi, J; Dolezal, Z; Donadelli, M; Donati, S; Dondero, P; Donini, J; Dopke, J; Doria, A; Dova, M T; Doyle, A T; Drechsler, E; Dris, M; Du, Y; Duarte-Campderros, J; Duchovni, E; Duckeck, G; Ducu, O A; Duda, D; Dudarev, A; Dudder, A Chr; Duffield, E M; Duflot, L; Dührssen, M; Dumancic, M; Duncan, A K; Dunford, M; Duran Yildiz, H; Düren, M; Durglishvili, A; Duschinger, D; Dutta, B; Dyndal, M; Eckardt, C; Ecker, K M; Edgar, R C; Edwards, N C; Eifert, T; Eigen, G; Einsweiler, K; Ekelof, T; Kacimi, M El; Ellajosyula, V; Ellert, M; Elles, S; Ellinghaus, F; Elliot, A A; Ellis, N; Elmsheuser, J; Elsing, M; Emeliyanov, D; Enari, Y; Endner, O C; Ennis, J S; Erdmann, J; Ereditato, A; Ernis, G; Ernst, J; Ernst, M; Errede, S; Ertel, E; Escalier, M; Esch, H; Escobar, C; Esposito, B; Etienvre, A I; Etzion, E; Evans, H; Ezhilov, A; Fabbri, F; Fabbri, L; Facini, G; Fakhrutdinov, R M; Falciano, S; Falla, R J; Faltova, J; Fang, Y; Fanti, M; Farbin, A; Farilla, A; Farina, C; Farina, E M; Farooque, T; Farrell, S; Farrington, S M; Farthouat, P; Fassi, F; Fassnacht, P; Fassouliotis, D; Faucci Giannelli, M; Favareto, A; Fawcett, W J; Fayard, L; Fedin, O L; Fedorko, W; Feigl, S; Feligioni, L; Feng, C; Feng, E J; Feng, H; Fenyuk, A B; Feremenga, L; Fernandez Martinez, P; Fernandez Perez, S; Ferrando, J; Ferrari, A; Ferrari, P; Ferrari, R; de Lima, D E Ferreira; Ferrer, A; Ferrere, D; Ferretti, C; Fiedler, F; Filipčič, A; Filipuzzi, M; Filthaut, F; Fincke-Keeler, M; Finelli, K D; Fiolhais, M C N; Fiorini, L; Fischer, A; Fischer, C; Fischer, J; Fisher, W C; Flaschel, N; Fleck, I; Fleischmann, P; Fletcher, G T; Fletcher, R R M; Flick, T; Flierl, B M; Flores Castillo, L R; Flowerdew, M J; Forcolin, G T; Formica, A; Forti, A; Foster, A G; Fournier, D; Fox, H; Fracchia, S; Francavilla, P; Franchini, M; Francis, D; Franconi, L; Franklin, M; Frate, M; Fraternali, M; Freeborn, D; Fressard-Batraneanu, S M; Friedrich, F; Froidevaux, D; Frost, J A; Fukunaga, C; Fullana Torregrosa, E; Fusayasu, T; Fuster, J; Gabaldon, C; Gabizon, O; Gabrielli, A; Gabrielli, A; Gach, G P; Gadatsch, S; Gagliardi, G; Gagnon, L G; Gagnon, P; Galea, C; Galhardo, B; Gallas, E J; Gallop, B J; Gallus, P; Galster, G; Gan, K K; Ganguly, S; Gao, J; Gao, Y; Gao, Y S; Garay Walls, F M; García, C; García Navarro, J E; Garcia-Sciveres, M; Gardner, R W; Garelli, N; Garonne, V; Gascon Bravo, A; Gasnikova, K; Gatti, C; Gaudiello, A; Gaudio, G; Gauthier, L; Gavrilenko, I L; Gay, C; Gaycken, G; Gazis, E N; Gecse, Z; Gee, C N P; Geich-Gimbel, Ch; Geisen, M; Geisler, M P; Gellerstedt, K; Gemme, C; Genest, M H; Geng, C; Gentile, S; Gentsos, C; George, S; Gerbaudo, D; Gershon, A; Ghasemi, S; Ghneimat, M; Giacobbe, B; Giagu, S; Giannetti, P; Gibson, S M; Gignac, M; Gilchriese, M; Gillam, T P S; Gillberg, D; Gilles, G; Gingrich, D M; Giokaris, N; Giordani, M P; Giorgi, F M; Giraud, P F; Giromini, P; Giugni, D; Giuli, F; Giuliani, C; Giulini, M; Gjelsten, B K; Gkaitatzis, S; Gkialas, I; Gkougkousis, E L; Gladilin, L K; Glasman, C; Glatzer, J; Glaysher, P C F; Glazov, A; Goblirsch-Kolb, M; Godlewski, J; Goldfarb, S; Golling, T; Golubkov, D; Gomes, A; Gonçalo, R; Da Costa, J Goncalves Pinto Firmino; Gonella, G; Gonella, L; Gongadze, A; de la Hoz, S González; Gonzalez-Sevilla, S; Goossens, L; Gorbounov, P A; Gordon, H A; Gorelov, I; Gorini, B; Gorini, E; Gorišek, A; Goshaw, A T; Gössling, C; Gostkin, M I; Goudet, C R; Goujdami, D; Goussiou, A G; Govender, N; Gozani, E; Graber, L; Grabowska-Bold, I; Gradin, P O J; Grafström, P; Gramling, J; Gramstad, E; Grancagnolo, S; Gratchev, V; Gravila, P M; Gray, H M; Graziani, E; Greenwood, Z D; Grefe, C; Gregersen, K; Gregor, I M; Grenier, P; Grevtsov, K; Griffiths, J; Grillo, A A; Grimm, K; Grinstein, S; Gris, Ph; Grivaz, J-F; Groh, S; Gross, E; Grosse-Knetter, J; Grossi, G C; Grout, Z J; Guan, L; Guan, W; Guenther, J; Guescini, F; Guest, D; Gueta, O; Gui, B; Guido, E; Guillemin, T; Guindon, S; Gul, U; Gumpert, C; Guo, J; Guo, W; Guo, Y; Gupta, R; Gupta, S; Gustavino, G; Gutierrez, P; Gutierrez Ortiz, N G; Gutschow, C; Guyot, C; Gwenlan, C; Gwilliam, C B; Haas, A; Haber, C; Hadavand, H K; Hadef, A; Hageböck, S; Hagihara, M; Hakobyan, H; Haleem, M; Haley, J; Halladjian, G; Hallewell, G D; Hamacher, K; Hamal, P; Hamano, K; Hamilton, A; Hamity, G N; Hamnett, P G; Han, L; Han, S; Hanagaki, K; Hanawa, K; Hance, M; Haney, B; Hanke, P; Hanna, R; Hansen, J B; Hansen, J D; Hansen, M C; Hansen, P H; Hara, K; Hard, A S; Harenberg, T; Hariri, F; Harkusha, S; Harrington, R D; Harrison, P F; Hartjes, F; Hartmann, N M; Hasegawa, M; Hasegawa, Y; Hasib, A; Hassani, S; Haug, S; Hauser, R; Hauswald, L; Havranek, M; Hawkes, C M; Hawkings, R J; Hayakawa, D; Hayden, D; Hays, C P; Hays, J M; Hayward, H S; Haywood, S J; Head, S J; Heck, T; Hedberg, V; Heelan, L; Heim, S; Heim, T; Heinemann, B; Heinrich, J J; Heinrich, L; Heinz, C; Hejbal, J; Helary, L; Hellman, S; Helsens, C; Henderson, J; Henderson, R C W; Heng, Y; Henkelmann, S; Henriques Correia, A M; Henrot-Versille, S; Herbert, G H; Herde, H; Herget, V; Hernández Jiménez, Y; Herten, G; Hertenberger, R; Hervas, L; Hesketh, G G; Hessey, N P; Hetherly, J W; Higón-Rodriguez, E; Hill, E; Hill, J C; Hiller, K H; Hillier, S J; Hinchliffe, I; Hines, E; Hirose, M; Hirschbuehl, D; Hladik, O; Hoad, X; Hobbs, J; Hod, N; Hodgkinson, M C; Hodgson, P; Hoecker, A; Hoeferkamp, M R; Hoenig, F; Hohn, D; Holmes, T R; Homann, M; Honda, S; Honda, T; Hong, T M; Hooberman, B H; Hopkins, W H; Horii, Y; Horton, A J; Hostachy, J-Y; Hou, S; Hoummada, A; Howarth, J; Hoya, J; Hrabovsky, M; Hristova, I; Hrivnac, J; Hryn'ova, T; Hrynevich, A; Hsu, P J; Hsu, S-C; Hu, Q; Hu, S; Huang, Y; Hubacek, Z; Hubaut, F; Huegging, F; Huffman, T B; Hughes, E W; Hughes, G; Huhtinen, M; Huo, P; Huseynov, N; Huston, J; Huth, J; Iacobucci, G; Iakovidis, G; Ibragimov, I; Iconomidou-Fayard, L; Ideal, E; Iengo, P; Igonkina, O; Iizawa, T; Ikegami, Y; Ikeno, M; Ilchenko, Y; Iliadis, D; Ilic, N; Introzzi, G; Ioannou, P; Iodice, M; Iordanidou, K; Ippolito, V; Ishijima, N; Ishino, M; Ishitsuka, M; Issever, C; Istin, S; Ito, F; Iturbe Ponce, J M; Iuppa, R; Iwasaki, H; Izen, J M; Izzo, V; Jabbar, S; Jackson, B; Jackson, P; Jain, V; Jakobi, K B; Jakobs, K; Jakobsen, S; Jakoubek, T; Jamin, D O; Jana, D K; Jansky, R; Janssen, J; Janus, M; Janus, P A; Jarlskog, G; Javadov, N; Javůrek, T; Javurkova, M; Jeanneau, F; Jeanty, L; Jejelava, J; Jeng, G-Y; Jenni, P; Jeske, C; Jézéquel, S; Ji, H; Jia, J; Jiang, H; Jiang, Y; Jiang, Z; Jiggins, S; Jimenez Pena, J; Jin, S; Jinaru, A; Jinnouchi, O; Jivan, H; Johansson, P; Johns, K A; Johnson, C A; Johnson, W J; Jon-And, K; Jones, G; Jones, R W L; Jones, S; Jones, T J; Jongmanns, J; Jorge, P M; Jovicevic, J; Ju, X; Juste Rozas, A; Köhler, M K; Kaczmarska, A; Kado, M; Kagan, H; Kagan, M; Kahn, S J; Kaji, T; Kajomovitz, E; Kalderon, C W; Kaluza, A; Kama, S; Kamenshchikov, A; Kanaya, N; Kaneti, S; Kanjir, L; Kantserov, V A; Kanzaki, J; Kaplan, B; Kaplan, L S; Kapliy, A; Kar, D; Karakostas, K; Karamaoun, A; Karastathis, N; Kareem, M J; Karentzos, E; Karnevskiy, M; Karpov, S N; Karpova, Z M; Karthik, K; Kartvelishvili, V; Karyukhin, A N; Kasahara, K; Kashif, L; Kass, R D; Kastanas, A; Kataoka, Y; Kato, C; Katre, A; Katzy, J; Kawade, K; Kawagoe, K; Kawamoto, T; Kawamura, G; Kazanin, V F; Keeler, R; Kehoe, R; Keller, J S; Kempster, J J; Keoshkerian, H; Kepka, O; Kerševan, B P; Kersten, S; Keyes, R A; Khader, M; Khalil-Zada, F; Khanov, A; Kharlamov, A G; Kharlamova, T; Khoo, T J; Khovanskiy, V; Khramov, E; Khubua, J; Kido, S; Kilby, C R; Kim, H Y; Kim, S H; Kim, Y K; Kimura, N; Kind, O M; King, B T; King, M; Kirk, J; Kiryunin, A E; Kishimoto, T; Kisielewska, D; Kiss, F; Kiuchi, K; Kivernyk, O; Kladiva, E; Klein, M H; Klein, M; Klein, U; Kleinknecht, K; Klimek, P; Klimentov, A; Klingenberg, R; Klioutchnikova, T; Kluge, E-E; Kluit, P; Kluth, S; Knapik, J; Kneringer, E; Knoops, E B F G; Knue, A; Kobayashi, A; Kobayashi, D; Kobayashi, T; Kobel, M; Kocian, M; Kodys, P; Koffas, T; Koffeman, E; Köhler, N M; Koi, T; Kolanoski, H; Kolb, M; Koletsou, I; Komar, A A; Komori, Y; Kondo, T; Kondrashova, N; Köneke, K; König, A C; Kono, T; Konoplich, R; Konstantinidis, N; Kopeliansky, R; Koperny, S; Kopp, A K; Korcyl, K; Kordas, K; Korn, A; Korol, A A; Korolkov, I; Korolkova, E V; Kortner, O; Kortner, S; Kosek, T; Kostyukhin, V V; Kotwal, A; Koulouris, A; Kourkoumeli-Charalampidi, A; Kourkoumelis, C; Kouskoura, V; Kowalewska, A B; Kowalewski, R; Kowalski, T Z; Kozakai, C; Kozanecki, W; Kozhin, A S; Kramarenko, V A; Kramberger, G; Krasnopevtsev, D; Krasny, M W; Krasznahorkay, A; Kravchenko, A; Kretz, M; Kretzschmar, J; Kreutzfeldt, K; Krieger, P; Krizka, K; Kroeninger, K; Kroha, H; Kroll, J; Kroseberg, J; Krstic, J; Kruchonak, U; Krüger, H; Krumnack, N; Kruse, M C; Kruskal, M; Kubota, T; Kucuk, H; Kuday, S; Kuechler, J T; Kuehn, S; Kugel, A; Kuger, F; Kuhl, T; Kukhtin, V; Kukla, R; Kulchitsky, Y; Kuleshov, S; Kuna, M; Kunigo, T; Kupco, A; Kuprash, O; Kurashige, H; Kurchaninov, L L; Kurochkin, Y A; Kurth, M G; Kus, V; Kuwertz, E S; Kuze, M; Kvita, J; Kwan, T; Kyriazopoulos, D; La Rosa, A; Rosa Navarro, J L La; La Rotonda, L; Lacasta, C; Lacava, F; Lacey, J; Lacker, H; Lacour, D; Ladygin, E; Lafaye, R; Laforge, B; Lagouri, T; Lai, S; Lammers, S; Lampl, W; Lançon, E; Landgraf, U; Landon, M P J; Lanfermann, M C; Lang, V S; Lange, J C; Lankford, A J; Lanni, F; Lantzsch, K; Lanza, A; Laplace, S; Lapoire, C; Laporte, J F; Lari, T; Lasagni Manghi, F; Lassnig, M; Laurelli, P; Lavrijsen, W; Law, A T; Laycock, P; Lazovich, T; Lazzaroni, M; Le, B; Le Dortz, O; Le Guirriec, E; Le Quilleuc, E P; LeBlanc, M; LeCompte, T; Ledroit-Guillon, F; Lee, C A; Lee, S C; Lee, L; Lefebvre, B; Lefebvre, G; Lefebvre, M; Legger, F; Leggett, C; Lehan, A; Lehmann Miotto, G; Lei, X; Leight, W A; Leister, A G; Leite, M A L; Leitner, R; Lellouch, D; Lemmer, B; Leney, K J C; Lenz, T; Lenzi, B; Leone, R; Leone, S; Leonidopoulos, C; Leontsinis, S; Lerner, G; Leroy, C; Lesage, A A J; Lester, C G; Lester, C M; Levchenko, M; Levêque, J; Levin, D; Levinson, L J; Levy, M; Lewis, D; Leyton, M; Li, B; Li, C; Li, H; Li, L; Li, L; Li, Q; Li, S; Li, X; Li, Y; Liang, Z; Liberti, B; Liblong, A; Lichard, P; Lie, K; Liebal, J; Liebig, W; Limosani, A; Lin, S C; Lin, T H; Lindquist, B E; Lionti, A E; Lipeles, E; Lipniacka, A; Lisovyi, M; Liss, T M; Lister, A; Litke, A M; Liu, B; Liu, D; Liu, H; Liu, H; Liu, J; Liu, J B; Liu, K; Liu, L; Liu, M; Liu, Y L; Liu, Y; Livan, M; Lleres, A; Llorente Merino, J; Lloyd, S L; Lo Sterzo, F; Lobodzinska, E M; Loch, P; Loebinger, F K; Loew, K M; Loginov, A; Lohse, T; Lohwasser, K; Lokajicek, M; Long, B A; Long, J D; Long, R E; Longo, L; Looper, K A; Lopez, J A; Lopez Mateos, D; Lopez Paredes, B; Lopez Paz, I; Lopez Solis, A; Lorenz, J; Lorenzo Martinez, N; Losada, M; Lösel, P J; Lou, X; Lounis, A; Love, J; Love, P A; Lu, H; Lu, N; Lubatti, H J; Luci, C; Lucotte, A; Luedtke, C; Luehring, F; Lukas, W; Luminari, L; Lundberg, O; Lund-Jensen, B; Luzi, P M; Lynn, D; Lysak, R; Lytken, E; Lyubushkin, V; Ma, H; Ma, L L; Ma, Y; Maccarrone, G; Macchiolo, A; Macdonald, C M; Maček, B; Machado Miguens, J; Madaffari, D; Madar, R; Maddocks, H J; Mader, W F; Madsen, A; Maeda, J; Maeland, S; Maeno, T; Maevskiy, A; Magradze, E; Mahlstedt, J; Maiani, C; Maidantchik, C; Maier, A A; Maier, T; Maio, A; Majewski, S; Makida, Y; Makovec, N; Malaescu, B; Malecki, Pa; Maleev, V P; Malek, F; Mallik, U; Malon, D; Malone, C; Maltezos, S; Malyukov, S; Mamuzic, J; Mancini, G; Mandelli, L; Mandić, I; Maneira, J; de Andrade Filho, L Manhaes; Manjarres Ramos, J; Mann, A; Manousos, A; Mansoulie, B; Mansour, J D; Mantifel, R; Mantoani, M; Manzoni, S; Mapelli, L; Marceca, G; March, L; Marchiori, G; Marcisovsky, M; Marjanovic, M; Marley, D E; Marroquim, F; Marsden, S P; Marshall, Z; Marti-Garcia, S; Martin, B; Martin, T A; Martin, V J; Martin Dit Latour, B; Martinez, M; Martinez Outschoorn, V I; Martin-Haugh, S; Martoiu, V S; Martyniuk, A C; Marzin, A; Masetti, L; Mashimo, T; Mashinistov, R; Masik, J; Maslennikov, A L; Massa, I; Massa, L; Mastrandrea, P; Mastroberardino, A; Masubuchi, T; Mättig, P; Mattmann, J; Maurer, J; Maxfield, S J; Maximov, D A; Mazini, R; Maznas, I; Mazza, S M; Mc Fadden, N C; Goldrick, G Mc; Mc Kee, S P; McCarn, A; McCarthy, R L; McCarthy, T G; McClymont, L I; McDonald, E F; Mcfayden, J A; Mchedlidze, G; McMahon, S J; McPherson, R A; Medinnis, M; Meehan, S; Mehlhase, S; Mehta, A; Meier, K; Meineck, C; Meirose, B; Melini, D; Mellado Garcia, B R; Melo, M; Meloni, F; Menary, S B; Meng, L; Meng, X T; Mengarelli, A; Menke, S; Meoni, E; Mergelmeyer, S; Mermod, P; Merola, L; Meroni, C; Merritt, F S; Messina, A; Metcalfe, J; Mete, A S; Meyer, C; Meyer, C; Meyer, J-P; Meyer, J; Meyer Zu Theenhausen, H; Miano, F; Middleton, R P; Miglioranzi, S; Mijović, L; Mikenberg, G; Mikestikova, M; Mikuž, M; Milesi, M; Milic, A; Miller, D W; Mills, C; Milov, A; Milstead, D A; Minaenko, A A; Minami, Y; Minashvili, I A; Mincer, A I; Mindur, B; Mineev, M; Minegishi, Y; Ming, Y; Mir, L M; Mistry, K P; Mitani, T; Mitrevski, J; Mitsou, V A; Miucci, A; Miyagawa, P S; Mizukami, A; Mjörnmark, J U; Mlynarikova, M; Moa, T; Mochizuki, K; Mogg, P; Mohapatra, S; Molander, S; Moles-Valls, R; Monden, R; Mondragon, M C; Mönig, K; Monk, J; Monnier, E; Montalbano, A; Montejo Berlingen, J; Monticelli, F; Monzani, S; Moore, R W; Morange, N; Moreno, D; Moreno Llácer, M; Morettini, P; Morgenstern, S; Mori, D; Mori, T; Morii, M; Morinaga, M; Morisbak, V; Moritz, S; Morley, A K; Mornacchi, G; Morris, J D; Morvaj, L; Moschovakos, P; Mosidze, M; Moss, H J; Moss, J; Motohashi, K; Mount, R; Mountricha, E; Moyse, E J W; Muanza, S; Mudd, R D; Mueller, F; Mueller, J; Mueller, R S P; Mueller, T; Muenstermann, D; Mullen, P; Mullier, G A; Munoz Sanchez, F J; Murillo Quijada, J A; Murray, W J; Musheghyan, H; Muškinja, M; Myagkov, A G; Myska, M; Nachman, B P; Nackenhorst, O; Nagai, K; Nagai, R; Nagano, K; Nagasaka, Y; Nagata, K; Nagel, M; Nagy, E; Nairz, A M; Nakahama, Y; Nakamura, K; Nakamura, T; Nakano, I; Naranjo Garcia, R F; Narayan, R; Narrias Villar, D I; Naryshkin, I; Naumann, T; Navarro, G; Nayyar, R; Neal, H A; Nechaeva, P Yu; Neep, T J; Negri, A; Negrini, M; Nektarijevic, S; Nellist, C; Nelson, A; Nemecek, S; Nemethy, P; Nepomuceno, A A; Nessi, M; Neubauer, M S; Neumann, M; Neves, R M; Nevski, P; Newman, P R; Nguyen, D H; Nguyen Manh, T; Nickerson, R B; Nicolaidou, R; Nielsen, J; Nikolaenko, V; Nikolic-Audit, I; Nikolopoulos, K; Nilsen, J K; Nilsson, P; Ninomiya, Y; Nisati, A; Nisius, R; Nobe, T; Nomachi, M; Nomidis, I; Nooney, T; Norberg, S; Nordberg, M; Norjoharuddeen, N; Novgorodova, O; Nowak, S; Nozaki, M; Nozka, L; Ntekas, K; Nurse, E; Nuti, F; O'grady, F; O'Neil, D C; O'Rourke, A A; O'Shea, V; Oakham, F G; Oberlack, H; Obermann, T; Ocariz, J; Ochi, A; Ochoa, I; Ochoa-Ricoux, J P; Oda, S; Odaka, S; Ogren, H; Oh, A; Oh, S H; Ohm, C C; Ohman, H; Oide, H; Okawa, H; Okumura, Y; Okuyama, T; Olariu, A; Oleiro Seabra, L F; Olivares Pino, S A; Oliveira Damazio, D; Olszewski, A; Olszowska, J; Onofre, A; Onogi, K; Onyisi, P U E; Oreglia, M J; Oren, Y; Orestano, D; Orlando, N; Orr, R S; Osculati, B; Ospanov, R; Otero Y Garzon, G; Otono, H; Ouchrif, M; Ould-Saada, F; Ouraou, A; Oussoren, K P; Ouyang, Q; Owen, M; Owen, R E; Ozcan, V E; Ozturk, N; Pachal, K; Pacheco Pages, A; Pacheco Rodriguez, L; Padilla Aranda, C; Pagan Griso, S; Paganini, M; Paige, F; Pais, P; Pajchel, K; Palacino, G; Palazzo, S; Palestini, S; Palka, M; Pallin, D; Panagiotopoulou, E St; Panagoulias, I; Pandini, C E; Panduro Vazquez, J G; Pani, P; Panitkin, S; Pantea, D; Paolozzi, L; Papadopoulou, Th D; Papageorgiou, K; Paramonov, A; Paredes Hernandez, D; Parker, A J; Parker, M A; Parker, K A; Parodi, F; Parsons, J A; Parzefall, U; Pascuzzi, V R; Pasqualucci, E; Passaggio, S; Pastore, Fr; Pásztor, G; Pataraia, S; Pater, J R; Pauly, T; Pearce, J; Pearson, B; Pedersen, L E; Pedraza Lopez, S; Pedro, R; Peleganchuk, S V; Penc, O; Peng, C; Peng, H; Penwell, J; Peralva, B S; Perego, M M; Perepelitsa, D V; Perez Codina, E; Perini, L; Pernegger, H; Perrella, S; Peschke, R; Peshekhonov, V D; Peters, K; Peters, R F Y; Petersen, B A; Petersen, T C; Petit, E; Petridis, A; Petridou, C; Petroff, P; Petrolo, E; Petrov, M; Petrucci, F; Pettersson, N E; Peyaud, A; Pezoa, R; Phillips, P W; Piacquadio, G; Pianori, E; Picazio, A; Piccaro, E; Piccinini, M; Pickering, M A; Piegaia, R; Pilcher, J E; Pilkington, A D; Pin, A W J; Pinamonti, M; Pinfold, J L; Pingel, A; Pires, S; Pirumov, H; Pitt, M; Plazak, L; Pleier, M-A; Pleskot, V; Plotnikova, E; Pluth, D; Poettgen, R; Poggioli, L; Pohl, D; Polesello, G; Poley, A; Policicchio, A; Polifka, R; Polini, A; Pollard, C S; Polychronakos, V; Pommès, K; Pontecorvo, L; Pope, B G; Popeneciu, G A; Poppleton, A; Pospisil, S; Potamianos, K; Potrap, I N; Potter, C J; Potter, C T; Poulard, G; Poveda, J; Pozdnyakov, V; Pozo Astigarraga, M E; Pralavorio, P; Pranko, A; Prell, S; Price, D; Price, L E; Primavera, M; Prince, S; Prokofiev, K; Prokoshin, F; Protopopescu, S; Proudfoot, J; Przybycien, M; Puddu, D; Purohit, M; Puzo, P; Qian, J; Qin, G; Qin, Y; Quadt, A; Quayle, W B; Queitsch-Maitland, M; Quilty, D; Raddum, S; Radeka, V; Radescu, V; Radhakrishnan, S K; Radloff, P; Rados, P; Ragusa, F; Rahal, G; Raine, J A; Rajagopalan, S; Rammensee, M; Rangel-Smith, C; Ratti, M G; Rauch, D M; Rauscher, F; Rave, S; Ravenscroft, T; Ravinovich, I; Raymond, M; Read, A L; Readioff, N P; Reale, M; Rebuzzi, D M; Redelbach, A; Redlinger, G; Reece, R; Reed, R G; Reeves, K; Rehnisch, L; Reichert, J; Reiss, A; Rembser, C; Ren, H; Rescigno, M; Resconi, S; Resseguie, E D; Rezanova, O L; Reznicek, P; Rezvani, R; Richter, R; Richter, S; Richter-Was, E; Ricken, O; Ridel, M; Rieck, P; Riegel, C J; Rieger, J; Rifki, O; Rijssenbeek, M; Rimoldi, A; Rimoldi, M; Rinaldi, L; Ristić, B; Ritsch, E; Riu, I; Rizatdinova, F; Rizvi, E; Rizzi, C; Roberts, R T; Robertson, S H; Robichaud-Veronneau, A; Robinson, D; Robinson, J E M; Robson, A; Roda, C; Rodina, Y; Rodriguez Perez, A; Rodriguez, D; Roe, S; Rogan, C S; Røhne, O; Roloff, J; Romaniouk, A; Romano, M; Saez, S M Romano; Romero Adam, E; Rompotis, N; Ronzani, M; Roos, L; Ros, E; Rosati, S; Rosbach, K; Rose, P; Rosien, N-A; Rossetti, V; Rossi, E; Rossi, L P; Rosten, J H N; Rosten, R; Rotaru, M; Roth, I; Rothberg, J; Rousseau, D; Rozanov, A; Rozen, Y; Ruan, X; Rubbo, F; Rudolph, M S; Rühr, F; Ruiz-Martinez, A; Rurikova, Z; Rusakovich, N A; Ruschke, A; Russell, H L; Rutherfoord, J P; Ruthmann, N; Ryabov, Y F; Rybar, M; Rybkin, G; Ryu, S; Ryzhov, A; Rzehorz, G F; Saavedra, A F; Sabato, G; Sacerdoti, S; Sadrozinski, H F-W; Sadykov, R; Safai Tehrani, F; Saha, P; Sahinsoy, M; Saimpert, M; Saito, T; Sakamoto, H; Sakurai, Y; Salamanna, G; Salamon, A; Salazar Loyola, J E; Salek, D; De Bruin, P H Sales; Salihagic, D; Salnikov, A; Salt, J; Salvatore, D; Salvatore, F; Salvucci, A; Salzburger, A; Sammel, D; Sampsonidis, D; Sánchez, J; Sanchez Martinez, V; Pineda, A Sanchez; Sandaker, H; Sandbach, R L; Sandhoff, M; Sandoval, C; Sankey, D P C; Sannino, M; Sansoni, A; Santoni, C; Santonico, R; Santos, H; Santoyo Castillo, I; Sapp, K; Sapronov, A; Saraiva, J G; Sarrazin, B; Sasaki, O; Sato, K; Sauvan, E; Savage, G; Savard, P; Savic, N; Sawyer, C; Sawyer, L; Saxon, J; Sbarra, C; Sbrizzi, A; Scanlon, T; Scannicchio, D A; Scarcella, M; Scarfone, V; Schaarschmidt, J; Schacht, P; Schachtner, B M; Schaefer, D; Schaefer, L; Schaefer, R; Schaeffer, J; Schaepe, S; Schaetzel, S; Schäfer, U; Schaffer, A C; Schaile, D; Schamberger, R D; Scharf, V; Schegelsky, V A; Scheirich, D; Schernau, M; Schiavi, C; Schier, S; Schillo, C; Schioppa, M; Schlenker, S; Schmidt-Sommerfeld, K R; Schmieden, K; Schmitt, C; Schmitt, S; Schmitz, S; Schneider, B; Schnoor, U; Schoeffel, L; Schoening, A; Schoenrock, B D; Schopf, E; Schott, M; Schouwenberg, J F P; Schovancova, J; Schramm, S; Schreyer, M; Schuh, N; Schulte, A; Schultens, M J; Schultz-Coulon, H-C; Schulz, H; Schumacher, M; Schumm, B A; Schune, Ph; Schwartzman, A; Schwarz, T A; Schweiger, H; Schwemling, Ph; Schwienhorst, R; Schwindling, J; Schwindt, T; Sciolla, G; Scuri, F; Scutti, F; Searcy, J; Seema, P; Seidel, S C; Seiden, A; Seifert, F; Seixas, J M; Sekhniaidze, G; Sekhon, K; Sekula, S J; Seliverstov, D M; Semprini-Cesari, N; Serfon, C; Serin, L; Serkin, L; Serre, T; Sessa, M; Seuster, R; Severini, H; Sfiligoj, T; Sforza, F; Sfyrla, A; Shabalina, E; Shaikh, N W; Shan, L Y; Shang, R; Shank, J T; Shapiro, M; Shatalov, P B; Shaw, K; Shaw, S M; Shcherbakova, A; Shehu, C Y; Sherwood, P; Shi, L; Shimizu, S; Shimmin, C O; Shimojima, M; Shirabe, S; Shiyakova, M; Shmeleva, A; Shoaleh Saadi, D; Shochet, M J; Shojaii, S; Shope, D R; Shrestha, S; Shulga, E; Shupe, M A; Sicho, P; Sickles, A M; Sidebo, P E; Sideras Haddad, E; Sidiropoulou, O; Sidorov, D; Sidoti, A; Siegert, F; Sijacki, Dj; Silva, J; Silverstein, S B; Simak, V; Simic, Lj; Simion, S; Simioni, E; Simmons, B; Simon, D; Simon, M; Sinervo, P; Sinev, N B; Sioli, M; Siragusa, G; Siral, I; Sivoklokov, S Yu; Sjölin, J; Skinner, M B; Skottowe, H P; Skubic, P; Slater, M; Slavicek, T; Slawinska, M; Sliwa, K; Slovak, R; Smakhtin, V; Smart, B H; Smestad, L; Smiesko, J; Smirnov, S Yu; Smirnov, Y; Smirnova, L N; Smirnova, O; Smith, J W; Smith, M N K; Smith, R W; Smizanska, M; Smolek, K; Snesarev, A A; Snyder, I M; Snyder, S; Sobie, R; Socher, F; Soffer, A; Soh, D A; Sokhrannyi, G; Solans Sanchez, C A; Solar, M; Soldatov, E Yu; Soldevila, U; Solodkov, A A; Soloshenko, A; Solovyanov, O V; Solovyev, V; Sommer, P; Son, H; Song, H Y; Sood, A; Sopczak, A; Sopko, V; Sorin, V; Sosa, D; Sotiropoulou, C L; Soualah, R; Soukharev, A M; South, D; Sowden, B C; Spagnolo, S; Spalla, M; Spangenberg, M; Spanò, F; Sperlich, D; Spettel, F; Spighi, R; Spigo, G; Spiller, L A; Spousta, M; Denis, R D St; Stabile, A; Stamen, R; Stamm, S; Stanecka, E; Stanek, R W; Stanescu, C; Stanescu-Bellu, M; Stanitzki, M M; Stapnes, S; Starchenko, E A; Stark, G H; Stark, J; Stark, S H; Staroba, P; Starovoitov, P; Stärz, S; Staszewski, R; Steinberg, P; Stelzer, B; Stelzer, H J; Stelzer-Chilton, O; Stenzel, H; Stewart, G A; Stillings, J A; Stockton, M C; Stoebe, M; Stoicea, G; Stolte, P; Stonjek, S; Stradling, A R; Straessner, A; Stramaglia, M E; Strandberg, J; Strandberg, S; Strandlie, A; Strauss, M; Strizenec, P; Ströhmer, R; Strom, D M; Stroynowski, R; Strubig, A; Stucci, S A; Stugu, B; Styles, N A; Su, D; Su, J; Suchek, S; Sugaya, Y; Suk, M; Sulin, V V; Sultansoy, S; Sumida, T; Sun, S; Sun, X; Sundermann, J E; Suruliz, K; Suster, C J E; Sutton, M R; Suzuki, S; Svatos, M; Swiatlowski, M; Swift, S P; Sykora, I; Sykora, T; Ta, D; Tackmann, K; Taenzer, J; Taffard, A; Tafirout, R; Taiblum, N; Takai, H; Takashima, R; Takeshita, T; Takubo, Y; Talby, M; Talyshev, A A; Tanaka, J; Tanaka, M; Tanaka, R; Tanaka, S; Tanioka, R; Tannenwald, B B; Tapia Araya, S; Tapprogge, S; Tarem, S; Tartarelli, G F; Tas, P; Tasevsky, M; Tashiro, T; Tassi, E; Tavares Delgado, A; Tayalati, Y; Taylor, A C; Taylor, G N; Taylor, P T E; Taylor, W; Teischinger, F A; Teixeira-Dias, P; Temming, K K; Temple, D; Ten Kate, H; Teng, P K; Teoh, J J; Tepel, F; Terada, S; Terashi, K; Terron, J; Terzo, S; Testa, M; Teuscher, R J; Theveneaux-Pelzer, T; Thomas, J P; Thomas-Wilsker, J; Thompson, P D; Thompson, A S; Thomsen, L A; Thomson, E; Tibbetts, M J; Ticse Torres, R E; Tikhomirov, V O; Tikhonov, Yu A; Timoshenko, S; Tiouchichine, E; Tipton, P; Tisserant, S; Todome, K; Todorov, T; Todorova-Nova, S; Tojo, J; Tokár, S; Tokushuku, K; Tolley, E; Tomlinson, L; Tomoto, M; Tompkins, L; Toms, K; Tong, B; Tornambe, P; Torrence, E; Torres, H; Torró Pastor, E; Toth, J; Touchard, F; Tovey, D R; Trefzger, T; Tricoli, A; Trigger, I M; Trincaz-Duvoid, S; Tripiana, M F; Trischuk, W; Trocmé, B; Trofymov, A; Troncon, C; Trottier-McDonald, M; Trovatelli, M; Truong, L; Trzebinski, M; Trzupek, A; Tseng, J C-L; Tsiareshka, P V; Tsipolitis, G; Tsirintanis, N; Tsiskaridze, S; Tsiskaridze, V; Tskhadadze, E G; Tsui, K M; Tsukerman, I I; Tsulaia, V; Tsuno, S; Tsybychev, D; Tu, Y; Tudorache, A; Tudorache, V; Tulbure, T T; Tuna, A N; Tupputi, S A; Turchikhin, S; Turgeman, D; Turk Cakir, I; Turra, R; Tuts, P M; Ucchielli, G; Ueda, I; Ughetto, M; Ukegawa, F; Unal, G; Undrus, A; Unel, G; Ungaro, F C; Unno, Y; Unverdorben, C; Urban, J; Urquijo, P; Urrejola, P; Usai, G; Usui, J; Vacavant, L; Vacek, V; Vachon, B; Valderanis, C; Valdes Santurio, E; Valencic, N; Valentinetti, S; Valero, A; Valery, L; Valkar, S; Valls Ferrer, J A; Van Den Wollenberg, W; Van Der Deijl, P C; van der Graaf, H; van Eldik, N; van Gemmeren, P; Van Nieuwkoop, J; van Vulpen, I; van Woerden, M C; Vanadia, M; Vandelli, W; Vanguri, R; Vaniachine, A; Vankov, P; Vardanyan, G; Vari, R; Varnes, E W; Varol, T; Varouchas, D; Vartapetian, A; Varvell, K E; Vasquez, J G; Vasquez, G A; Vazeille, F; Vazquez Schroeder, T; Veatch, J; Veeraraghavan, V; Veloce, L M; Veloso, F; Veneziano, S; Ventura, A; Venturi, M; Venturi, N; Venturini, A; Vercesi, V; Verducci, M; Verkerke, W; Vermeulen, J C; Vest, A; Vetterli, M C; Viazlo, O; Vichou, I; Vickey, T; Vickey Boeriu, O E; Viehhauser, G H A; Viel, S; Vigani, L; Villa, M; Villaplana Perez, M; Vilucchi, E; Vincter, M G; Vinogradov, V B; Vittori, C; Vivarelli, I; Vlachos, S; Vlasak, M; Vogel, M; Vokac, P; Volpi, G; Volpi, M; von der Schmitt, H; von Toerne, E; Vorobel, V; Vorobev, K; Vos, M; Voss, R; Vossebeld, J H; Vranjes, N; Vranjes Milosavljevic, M; Vrba, V; Vreeswijk, M; Vuillermet, R; Vukotic, I; Wagner, P; Wagner, W; Wahlberg, H; Wahrmund, S; Wakabayashi, J; Walder, J; Walker, R; Walkowiak, W; Wallangen, V; Wang, C; Wang, C; Wang, F; Wang, H; Wang, H; Wang, J; Wang, J; Wang, K; Wang, R; Wang, S M; Wang, T; Wang, W; Wanotayaroj, C; Warburton, A; Ward, C P; Wardrope, D R; Washbrook, A; Watkins, P M; Watson, A T; Watson, M F; Watts, G; Watts, S; Waugh, B M; Webb, S; Weber, M S; Weber, S W; Weber, S A; Webster, J S; Weidberg, A R; Weinert, B; Weingarten, J; Weiser, C; Weits, H; Wells, P S; Wenaus, T; Wengler, T; Wenig, S; Wermes, N; Werner, M D; Werner, P; Wessels, M; Wetter, J; Whalen, K; Whallon, N L; Wharton, A M; White, A; White, M J; White, R; Whiteson, D; Wickens, F J; Wiedenmann, W; Wielers, M; Wiglesworth, C; Wiik-Fuchs, L A M; Wildauer, A; Wilk, F; Wilkens, H G; Williams, H H; Williams, S; Willis, C; Willocq, S; Wilson, J A; Wingerter-Seez, I; Winklmeier, F; Winston, O J; Winter, B T; Wittgen, M; Wolf, T M H; Wolff, R; Wolter, M W; Wolters, H; Worm, S D; Wosiek, B K; Wotschack, J; Woudstra, M J; Wozniak, K W; Wu, M; Wu, M; Wu, S L; Wu, X; Wu, Y; Wyatt, T R; Wynne, B M; Xella, S; Xi, Z; Xu, D; Xu, L; Yabsley, B; Yacoob, S; Yamaguchi, D; Yamaguchi, Y; Yamamoto, A; Yamamoto, S; Yamanaka, T; Yamauchi, K; Yamazaki, Y; Yan, Z; Yang, H; Yang, H; Yang, Y; Yang, Z; Yao, W-M; Yap, Y C; Yasu, Y; Yatsenko, E; Yau Wong, K H; Ye, J; Ye, S; Yeletskikh, I; Yildirim, E; Yorita, K; Yoshida, R; Yoshihara, K; Young, C; Young, C J S; Youssef, S; Yu, D R; Yu, J; Yu, J M; Yu, J; Yuan, L; Yuen, S P Y; Yusuff, I; Zabinski, B; Zacharis, G; Zaidan, R; Zaitsev, A M; Zakharchuk, N; Zalieckas, J; Zaman, A; Zambito, S; Zanello, L; Zanzi, D; Zeitnitz, C; Zeman, M; Zemla, A; Zeng, J C; Zeng, Q; Zenin, O; Ženiš, T; Zerwas, D; Zhang, D; Zhang, F; Zhang, G; Zhang, H; Zhang, J; Zhang, L; Zhang, L; Zhang, M; Zhang, R; Zhang, R; Zhang, X; Zhang, Y; Zhang, Z; Zhao, X; Zhao, Y; Zhao, Z; Zhemchugov, A; Zhong, J; Zhou, B; Zhou, C; Zhou, L; Zhou, L; Zhou, M; Zhou, M; Zhou, N; Zhu, C G; Zhu, H; Zhu, J; Zhu, Y; Zhuang, X; Zhukov, K; Zibell, A; Zieminska, D; Zimine, N I; Zimmermann, C; Zimmermann, S; Zinonos, Z; Zinser, M; Ziolkowski, M; Živković, L; Zobernig, G; Zoccoli, A; Zur Nedden, M; Zwalinski, L

2017-01-01

This paper describes the algorithms for the reconstruction and identification of electrons in the central region of the ATLAS detector at the Large Hadron Collider (LHC). These algorithms were used for all ATLAS results with electrons in the final state that are based on the 2012 pp collision data produced by the LHC at [Formula: see text] = 8 [Formula: see text]. The efficiency of these algorithms, together with the charge misidentification rate, is measured in data and evaluated in simulated samples using electrons from [Formula: see text], [Formula: see text] and [Formula: see text] decays. For these efficiency measurements, the full recorded data set, corresponding to an integrated luminosity of 20.3 fb[Formula: see text], is used. Based on a new reconstruction algorithm used in 2012, the electron reconstruction efficiency is 97% for electrons with [Formula: see text] [Formula: see text] and 99% at [Formula: see text] [Formula: see text]. Combining this with the efficiency of additional selection criteria to reject electrons from background processes or misidentified hadrons, the efficiency to reconstruct and identify electrons at the ATLAS experiment varies from 65 to 95%, depending on the transverse momentum of the electron and background rejection.
Wavelet compression of multichannel ECG data by enhanced set partitioning in hierarchical trees algorithm.

PubMed

Sharifahmadian, Ershad

2006-01-01

The set partitioning in hierarchical trees (SPIHT) algorithm is very effective and computationally simple technique for image and signal compression. Here the author modified the algorithm which provides even better performance than the SPIHT algorithm. The enhanced set partitioning in hierarchical trees (ESPIHT) algorithm has performance faster than the SPIHT algorithm. In addition, the proposed algorithm reduces the number of bits in a bit stream which is stored or transmitted. I applied it to compression of multichannel ECG data. Also, I presented a specific procedure based on the modified algorithm for more efficient compression of multichannel ECG data. This method employed on selected records from the MIT-BIH arrhythmia database. According to experiments, the proposed method attained the significant results regarding compression of multichannel ECG data. Furthermore, in order to compress one signal which is stored for a long time, the proposed multichannel compression method can be utilized efficiently.
Test Generation Algorithm for Fault Detection of Analog Circuits Based on Extreme Learning Machine

PubMed Central

Zhou, Jingyu; Tian, Shulin; Yang, Chenglin; Ren, Xuelong

2014-01-01

This paper proposes a novel test generation algorithm based on extreme learning machine (ELM), and such algorithm is cost-effective and low-risk for analog device under test (DUT). This method uses test patterns derived from the test generation algorithm to stimulate DUT, and then samples output responses of the DUT for fault classification and detection. The novel ELM-based test generation algorithm proposed in this paper contains mainly three aspects of innovation. Firstly, this algorithm saves time efficiently by classifying response space with ELM. Secondly, this algorithm can avoid reduced test precision efficiently in case of reduction of the number of impulse-response samples. Thirdly, a new process of test signal generator and a test structure in test generation algorithm are presented, and both of them are very simple. Finally, the abovementioned improvement and functioning are confirmed in experiments. PMID:25610458
Efficiency Analysis of the Parallel Implementation of the SIMPLE Algorithm on Multiprocessor Computers

NASA Astrophysics Data System (ADS)

Lashkin, S. V.; Kozelkov, A. S.; Yalozo, A. V.; Gerasimov, V. Yu.; Zelensky, D. K.

2017-12-01

This paper describes the details of the parallel implementation of the SIMPLE algorithm for numerical solution of the Navier-Stokes system of equations on arbitrary unstructured grids. The iteration schemes for the serial and parallel versions of the SIMPLE algorithm are implemented. In the description of the parallel implementation, special attention is paid to computational data exchange among processors under the condition of the grid model decomposition using fictitious cells. We discuss the specific features for the storage of distributed matrices and implementation of vector-matrix operations in parallel mode. It is shown that the proposed way of matrix storage reduces the number of interprocessor exchanges. A series of numerical experiments illustrates the effect of the multigrid SLAE solver tuning on the general efficiency of the algorithm; the tuning involves the types of the cycles used (V, W, and F), the number of iterations of a smoothing operator, and the number of cells for coarsening. Two ways (direct and indirect) of efficiency evaluation for parallelization of the numerical algorithm are demonstrated. The paper presents the results of solving some internal and external flow problems with the evaluation of parallelization efficiency by two algorithms. It is shown that the proposed parallel implementation enables efficient computations for the problems on a thousand processors. Based on the results obtained, some general recommendations are made for the optimal tuning of the multigrid solver, as well as for selecting the optimal number of cells per processor.
Searching for efficient Markov chain Monte Carlo proposal kernels

PubMed Central

Yang, Ziheng; Rodríguez, Carlos E.

2013-01-01

Markov chain Monte Carlo (MCMC) or the Metropolis–Hastings algorithm is a simulation algorithm that has made modern Bayesian statistical inference possible. Nevertheless, the efficiency of different Metropolis–Hastings proposal kernels has rarely been studied except for the Gaussian proposal. Here we propose a unique class of Bactrian kernels, which avoid proposing values that are very close to the current value, and compare their efficiency with a number of proposals for simulating different target distributions, with efficiency measured by the asymptotic variance of a parameter estimate. The uniform kernel is found to be more efficient than the Gaussian kernel, whereas the Bactrian kernel is even better. When optimal scales are used for both, the Bactrian kernel is at least 50% more efficient than the Gaussian. Implementation in a Bayesian program for molecular clock dating confirms the general applicability of our results to generic MCMC algorithms. Our results refute a previous claim that all proposals had nearly identical performance and will prompt further research into efficient MCMC proposals. PMID:24218600
Efficient Actor-Critic Algorithm with Hierarchical Model Learning and Planning

PubMed Central

Fu, QiMing

2016-01-01

To improve the convergence rate and the sample efficiency, two efficient learning methods AC-HMLP and RAC-HMLP (AC-HMLP with ℓ 2-regularization) are proposed by combining actor-critic algorithm with hierarchical model learning and planning. The hierarchical models consisting of the local and the global models, which are learned at the same time during learning of the value function and the policy, are approximated by local linear regression (LLR) and linear function approximation (LFA), respectively. Both the local model and the global model are applied to generate samples for planning; the former is used only if the state-prediction error does not surpass the threshold at each time step, while the latter is utilized at the end of each episode. The purpose of taking both models is to improve the sample efficiency and accelerate the convergence rate of the whole algorithm through fully utilizing the local and global information. Experimentally, AC-HMLP and RAC-HMLP are compared with three representative algorithms on two Reinforcement Learning (RL) benchmark problems. The results demonstrate that they perform best in terms of convergence rate and sample efficiency. PMID:27795704
Efficient Actor-Critic Algorithm with Hierarchical Model Learning and Planning.

PubMed

Zhong, Shan; Liu, Quan; Fu, QiMing

2016-01-01

To improve the convergence rate and the sample efficiency, two efficient learning methods AC-HMLP and RAC-HMLP (AC-HMLP with ℓ 2 -regularization) are proposed by combining actor-critic algorithm with hierarchical model learning and planning. The hierarchical models consisting of the local and the global models, which are learned at the same time during learning of the value function and the policy, are approximated by local linear regression (LLR) and linear function approximation (LFA), respectively. Both the local model and the global model are applied to generate samples for planning; the former is used only if the state-prediction error does not surpass the threshold at each time step, while the latter is utilized at the end of each episode. The purpose of taking both models is to improve the sample efficiency and accelerate the convergence rate of the whole algorithm through fully utilizing the local and global information. Experimentally, AC-HMLP and RAC-HMLP are compared with three representative algorithms on two Reinforcement Learning (RL) benchmark problems. The results demonstrate that they perform best in terms of convergence rate and sample efficiency.
Efficient classical simulation of the Deutsch-Jozsa and Simon's algorithms

NASA Astrophysics Data System (ADS)

Johansson, Niklas; Larsson, Jan-Åke

2017-09-01

A long-standing aim of quantum information research is to understand what gives quantum computers their advantage. This requires separating problems that need genuinely quantum resources from those for which classical resources are enough. Two examples of quantum speed-up are the Deutsch-Jozsa and Simon's problem, both efficiently solvable on a quantum Turing machine, and both believed to lack efficient classical solutions. Here we present a framework that can simulate both quantum algorithms efficiently, solving the Deutsch-Jozsa problem with probability 1 using only one oracle query, and Simon's problem using linearly many oracle queries, just as expected of an ideal quantum computer. The presented simulation framework is in turn efficiently simulatable in a classical probabilistic Turing machine. This shows that the Deutsch-Jozsa and Simon's problem do not require any genuinely quantum resources, and that the quantum algorithms show no speed-up when compared with their corresponding classical simulation. Finally, this gives insight into what properties are needed in the two algorithms and calls for further study of oracle separation between quantum and classical computation.
Optimal Energy Efficiency Fairness of Nodes in Wireless Powered Communication Networks.

PubMed

Zhang, Jing; Zhou, Qingjie; Ng, Derrick Wing Kwan; Jo, Minho

2017-09-15

In wireless powered communication networks (WPCNs), it is essential to research energy efficiency fairness in order to evaluate the balance of nodes for receiving information and harvesting energy. In this paper, we propose an efficient iterative algorithm for optimal energy efficiency proportional fairness in WPCN. The main idea is to use stochastic geometry to derive the mean proportionally fairness utility function with respect to user association probability and receive threshold. Subsequently, we prove that the relaxed proportionally fairness utility function is a concave function for user association probability and receive threshold, respectively. At the same time, a sub-optimal algorithm by exploiting alternating optimization approach is proposed. Through numerical simulations, we demonstrate that our sub-optimal algorithm can obtain a result close to optimal energy efficiency proportional fairness with significant reduction of computational complexity.
Optimal Energy Efficiency Fairness of Nodes in Wireless Powered Communication Networks

PubMed Central

Zhou, Qingjie; Ng, Derrick Wing Kwan; Jo, Minho

2017-01-01

In wireless powered communication networks (WPCNs), it is essential to research energy efficiency fairness in order to evaluate the balance of nodes for receiving information and harvesting energy. In this paper, we propose an efficient iterative algorithm for optimal energy efficiency proportional fairness in WPCN. The main idea is to use stochastic geometry to derive the mean proportionally fairness utility function with respect to user association probability and receive threshold. Subsequently, we prove that the relaxed proportionally fairness utility function is a concave function for user association probability and receive threshold, respectively. At the same time, a sub-optimal algorithm by exploiting alternating optimization approach is proposed. Through numerical simulations, we demonstrate that our sub-optimal algorithm can obtain a result close to optimal energy efficiency proportional fairness with significant reduction of computational complexity. PMID:28914818
Broadband Gerchberg-Saxton algorithm for freeform diffractive spectral filter design.

PubMed

Vorndran, Shelby; Russo, Juan M; Wu, Yuechen; Pelaez, Silvana Ayala; Kostuk, Raymond K

2015-11-30

A multi-wavelength expansion of the Gerchberg-Saxton (GS) algorithm is developed to design and optimize a surface relief Diffractive Optical Element (DOE). The DOE simultaneously diffracts distinct wavelength bands into separate target regions. A description of the algorithm is provided, and parameters that affect filter performance are examined. Performance is based on the spectral power collected within specified regions on a receiver plane. The modified GS algorithm is used to design spectrum splitting optics for CdSe and Si photovoltaic (PV) cells. The DOE has average optical efficiency of 87.5% over the spectral bands of interest (400-710 nm and 710-1100 nm). Simulated PV conversion efficiency is 37.7%, which is 29.3% higher than the efficiency of the better performing PV cell without spectrum splitting optics.
An improved harmony search algorithm for emergency inspection scheduling

NASA Astrophysics Data System (ADS)

Kallioras, Nikos A.; Lagaros, Nikos D.; Karlaftis, Matthew G.

2014-11-01

The ability of nature-inspired search algorithms to efficiently handle combinatorial problems, and their successful implementation in many fields of engineering and applied sciences, have led to the development of new, improved algorithms. In this work, an improved harmony search (IHS) algorithm is presented, while a holistic approach for solving the problem of post-disaster infrastructure management is also proposed. The efficiency of IHS is compared with that of the algorithms of particle swarm optimization, differential evolution, basic harmony search and the pure random search procedure, when solving the districting problem that is the first part of post-disaster infrastructure management. The ant colony optimization algorithm is employed for solving the associated routing problem that constitutes the second part. The comparison is based on the quality of the results obtained, the computational demands and the sensitivity on the algorithmic parameters.
An Approximation of the Error Backpropagation Algorithm in a Predictive Coding Network with Local Hebbian Synaptic Plasticity

PubMed Central

Whittington, James C. R.; Bogacz, Rafal

2017-01-01

To efficiently learn from feedback, cortical networks need to update synaptic weights on multiple levels of cortical hierarchy. An effective and well-known algorithm for computing such changes in synaptic weights is the error backpropagation algorithm. However, in this algorithm, the change in synaptic weights is a complex function of weights and activities of neurons not directly connected with the synapse being modified, whereas the changes in biological synapses are determined only by the activity of presynaptic and postsynaptic neurons. Several models have been proposed that approximate the backpropagation algorithm with local synaptic plasticity, but these models require complex external control over the network or relatively complex plasticity rules. Here we show that a network developed in the predictive coding framework can efficiently perform supervised learning fully autonomously, employing only simple local Hebbian plasticity. Furthermore, for certain parameters, the weight change in the predictive coding model converges to that of the backpropagation algorithm. This suggests that it is possible for cortical networks with simple Hebbian synaptic plasticity to implement efficient learning algorithms in which synapses in areas on multiple levels of hierarchy are modified to minimize the error on the output. PMID:28333583
An Approximation of the Error Backpropagation Algorithm in a Predictive Coding Network with Local Hebbian Synaptic Plasticity.

PubMed

Whittington, James C R; Bogacz, Rafal

2017-05-01

To efficiently learn from feedback, cortical networks need to update synaptic weights on multiple levels of cortical hierarchy. An effective and well-known algorithm for computing such changes in synaptic weights is the error backpropagation algorithm. However, in this algorithm, the change in synaptic weights is a complex function of weights and activities of neurons not directly connected with the synapse being modified, whereas the changes in biological synapses are determined only by the activity of presynaptic and postsynaptic neurons. Several models have been proposed that approximate the backpropagation algorithm with local synaptic plasticity, but these models require complex external control over the network or relatively complex plasticity rules. Here we show that a network developed in the predictive coding framework can efficiently perform supervised learning fully autonomously, employing only simple local Hebbian plasticity. Furthermore, for certain parameters, the weight change in the predictive coding model converges to that of the backpropagation algorithm. This suggests that it is possible for cortical networks with simple Hebbian synaptic plasticity to implement efficient learning algorithms in which synapses in areas on multiple levels of hierarchy are modified to minimize the error on the output.
Computing rank-revealing QR factorizations of dense matrices.

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

Bischof, C. H.; Quintana-Orti, G.; Mathematics and Computer Science

1998-06-01

We develop algorithms and implementations for computing rank-revealing QR (RRQR) factorizations of dense matrices. First, we develop an efficient block algorithm for approximating an RRQR factorization, employing a windowed version of the commonly used Golub pivoting strategy, aided by incremental condition estimation. Second, we develop efficiently implementable variants of guaranteed reliable RRQR algorithms for triangular matrices originally suggested by Chandrasekaran and Ipsen and by Pan and Tang. We suggest algorithmic improvements with respect to condition estimation, termination criteria, and Givens updating. By combining the block algorithm with one of the triangular postprocessing steps, we arrive at an efficient and reliablemore » algorithm for computing an RRQR factorization of a dense matrix. Experimental results on IBM RS/6000 SGI R8000 platforms show that this approach performs up to three times faster that the less reliable QR factorization with column pivoting as it is currently implemented in LAPACK, and comes within 15% of the performance of the LAPACK block algorithm for computing a QR factorization without any column exchanges. Thus, we expect this routine to be useful in may circumstances where numerical rank deficiency cannot be ruled out, but currently has been ignored because of the computational cost of dealing with it.« less
New algorithm for tensor contractions on multi-core CPUs, GPUs, and accelerators enables CCSD and EOM-CCSD calculations with over 1000 basis functions on a single compute node.

PubMed

Kaliman, Ilya A; Krylov, Anna I

2017-04-30

A new hardware-agnostic contraction algorithm for tensors of arbitrary symmetry and sparsity is presented. The algorithm is implemented as a stand-alone open-source code libxm. This code is also integrated with general tensor library libtensor and with the Q-Chem quantum-chemistry package. An overview of the algorithm, its implementation, and benchmarks are presented. Similarly to other tensor software, the algorithm exploits efficient matrix multiplication libraries and assumes that tensors are stored in a block-tensor form. The distinguishing features of the algorithm are: (i) efficient repackaging of the individual blocks into large matrices and back, which affords efficient graphics processing unit (GPU)-enabled calculations without modifications of higher-level codes; (ii) fully asynchronous data transfer between disk storage and fast memory. The algorithm enables canonical all-electron coupled-cluster and equation-of-motion coupled-cluster calculations with single and double substitutions (CCSD and EOM-CCSD) with over 1000 basis functions on a single quad-GPU machine. We show that the algorithm exhibits predicted theoretical scaling for canonical CCSD calculations, O(N 6 ), irrespective of the data size on disk. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

Efficient and Stable Routing Algorithm Based on User Mobility and Node Density in Urban Vehicular Network.

PubMed

Al-Mayouf, Yusor Rafid Bahar; Ismail, Mahamod; Abdullah, Nor Fadzilah; Wahab, Ainuddin Wahid Abdul; Mahdi, Omar Adil; Khan, Suleman; Choo, Kim-Kwang Raymond

2016-01-01

Vehicular ad hoc networks (VANETs) are considered an emerging technology in the industrial and educational fields. This technology is essential in the deployment of the intelligent transportation system, which is targeted to improve safety and efficiency of traffic. The implementation of VANETs can be effectively executed by transmitting data among vehicles with the use of multiple hops. However, the intrinsic characteristics of VANETs, such as its dynamic network topology and intermittent connectivity, limit data delivery. One particular challenge of this network is the possibility that the contributing node may only remain in the network for a limited time. Hence, to prevent data loss from that node, the information must reach the destination node via multi-hop routing techniques. An appropriate, efficient, and stable routing algorithm must be developed for various VANET applications to address the issues of dynamic topology and intermittent connectivity. Therefore, this paper proposes a novel routing algorithm called efficient and stable routing algorithm based on user mobility and node density (ESRA-MD). The proposed algorithm can adapt to significant changes that may occur in the urban vehicular environment. This algorithm works by selecting an optimal route on the basis of hop count and link duration for delivering data from source to destination, thereby satisfying various quality of service considerations. The validity of the proposed algorithm is investigated by its comparison with ARP-QD protocol, which works on the mechanism of optimal route finding in VANETs in urban environments. Simulation results reveal that the proposed ESRA-MD algorithm shows remarkable improvement in terms of delivery ratio, delivery delay, and communication overhead.
An NAD(P)H:quinone oxidoreductase 1 (NQO1) enzyme responsive nanocarrier based on mesoporous silica nanoparticles for tumor targeted drug delivery in vitro and in vivo

NASA Astrophysics Data System (ADS)

Gayam, Srivardhan Reddy; Venkatesan, Parthiban; Sung, Yi-Ming; Sung, Shuo-Yuan; Hu, Shang-Hsiu; Hsu, Hsin-Yun; Wu, Shu-Pao

2016-06-01

The synthesis and characterization of an NAD(P)H:quinone oxidoreductase 1 (NQO1) enzyme responsive nanocarrier based on mesoporous silica nanoparticles (MSNPs) for on-command delivery applications has been described in this paper. Gatekeeping of MSNPs is achieved by the integration of mechanically interlocked rotaxane nanovalves on the surface of MSNPs. The rotaxane nanovalve system is composed of a linear stalk anchoring on the surface of MSNPs, an α-cyclodextrin ring that encircles it and locks the payload ``cargo'' molecules in the mesopores, and a benzoquinone stopper incorporated at the end of the stalk. The gate opening and controlled release of the cargo are triggered by cleavage of the benzoquinone stopper using an endogenous NQO1 enzyme. In addition to having efficient drug loading and controlled release mechanisms, this smart biocompatible carrier system showed obvious uptake and consequent release of the drug in tumor cells, could selectively induce the tumor cell death and enhance the capability of inhibition of tumor growth in vivo. The controlled drug delivery system demonstrated its use as a potential theranostic material.The synthesis and characterization of an NAD(P)H:quinone oxidoreductase 1 (NQO1) enzyme responsive nanocarrier based on mesoporous silica nanoparticles (MSNPs) for on-command delivery applications has been described in this paper. Gatekeeping of MSNPs is achieved by the integration of mechanically interlocked rotaxane nanovalves on the surface of MSNPs. The rotaxane nanovalve system is composed of a linear stalk anchoring on the surface of MSNPs, an α-cyclodextrin ring that encircles it and locks the payload ``cargo'' molecules in the mesopores, and a benzoquinone stopper incorporated at the end of the stalk. The gate opening and controlled release of the cargo are triggered by cleavage of the benzoquinone stopper using an endogenous NQO1 enzyme. In addition to having efficient drug loading and controlled release mechanisms, this smart biocompatible carrier system showed obvious uptake and consequent release of the drug in tumor cells, could selectively induce the tumor cell death and enhance the capability of inhibition of tumor growth in vivo. The controlled drug delivery system demonstrated its use as a potential theranostic material. Electronic supplementary information (ESI) available: Synthesis and characterization of the functional molecules and MSNPs is available in the ESI. See DOI: 10.1039/c6nr03525f
Hierarchical layered and semantic-based image segmentation using ergodicity map

NASA Astrophysics Data System (ADS)

Yadegar, Jacob; Liu, Xiaoqing

2010-04-01

Image segmentation plays a foundational role in image understanding and computer vision. Although great strides have been made and progress achieved on automatic/semi-automatic image segmentation algorithms, designing a generic, robust, and efficient image segmentation algorithm is still challenging. Human vision is still far superior compared to computer vision, especially in interpreting semantic meanings/objects in images. We present a hierarchical/layered semantic image segmentation algorithm that can automatically and efficiently segment images into hierarchical layered/multi-scaled semantic regions/objects with contextual topological relationships. The proposed algorithm bridges the gap between high-level semantics and low-level visual features/cues (such as color, intensity, edge, etc.) through utilizing a layered/hierarchical ergodicity map, where ergodicity is computed based on a space filling fractal concept and used as a region dissimilarity measurement. The algorithm applies a highly scalable, efficient, and adaptive Peano- Cesaro triangulation/tiling technique to decompose the given image into a set of similar/homogenous regions based on low-level visual cues in a top-down manner. The layered/hierarchical ergodicity map is built through a bottom-up region dissimilarity analysis. The recursive fractal sweep associated with the Peano-Cesaro triangulation provides efficient local multi-resolution refinement to any level of detail. The generated binary decomposition tree also provides efficient neighbor retrieval mechanisms for contextual topological object/region relationship generation. Experiments have been conducted within the maritime image environment where the segmented layered semantic objects include the basic level objects (i.e. sky/land/water) and deeper level objects in the sky/land/water surfaces. Experimental results demonstrate the proposed algorithm has the capability to robustly and efficiently segment images into layered semantic objects/regions with contextual topological relationships.
Computing border bases using mutant strategies

NASA Astrophysics Data System (ADS)

Ullah, E.; Abbas Khan, S.

2014-01-01

Border bases, a generalization of Gröbner bases, have actively been addressed during recent years due to their applicability to industrial problems. In cryptography and coding theory a useful application of border based is to solve zero-dimensional systems of polynomial equations over finite fields, which motivates us for developing optimizations of the algorithms that compute border bases. In 2006, Kehrein and Kreuzer formulated the Border Basis Algorithm (BBA), an algorithm which allows the computation of border bases that relate to a degree compatible term ordering. In 2007, J. Ding et al. introduced mutant strategies bases on finding special lower degree polynomials in the ideal. The mutant strategies aim to distinguish special lower degree polynomials (mutants) from the other polynomials and give them priority in the process of generating new polynomials in the ideal. In this paper we develop hybrid algorithms that use the ideas of J. Ding et al. involving the concept of mutants to optimize the Border Basis Algorithm for solving systems of polynomial equations over finite fields. In particular, we recall a version of the Border Basis Algorithm which is actually called the Improved Border Basis Algorithm and propose two hybrid algorithms, called MBBA and IMBBA. The new mutants variants provide us space efficiency as well as time efficiency. The efficiency of these newly developed hybrid algorithms is discussed using standard cryptographic examples.
Speedup of minimum discontinuity phase unwrapping algorithm with a reference phase distribution

NASA Astrophysics Data System (ADS)

Liu, Yihang; Han, Yu; Li, Fengjiao; Zhang, Qican

2018-06-01

In three-dimensional (3D) shape measurement based on phase analysis, the phase analysis process usually produces a wrapped phase map ranging from - π to π with some 2 π discontinuities, and thus a phase unwrapping algorithm is necessary to recover the continuous and nature phase map from which 3D height distribution can be restored. Usually, the minimum discontinuity phase unwrapping algorithm can be used to solve many different kinds of phase unwrapping problems, but its main drawback is that it requires a large amount of computations and has low efficiency in searching for the improving loop within the phase's discontinuity area. To overcome this drawback, an improvement to speedup of the minimum discontinuity phase unwrapping algorithm by using the phase distribution on reference plane is proposed. In this improved algorithm, before the minimum discontinuity phase unwrapping algorithm is carried out to unwrap phase, an integer number K was calculated from the ratio of the wrapped phase to the nature phase on a reference plane. And then the jump counts of the unwrapped phase can be reduced by adding 2K π, so the efficiency of the minimum discontinuity phase unwrapping algorithm is significantly improved. Both simulated and experimental data results verify the feasibility of the proposed improved algorithm, and both of them clearly show that the algorithm works very well and has high efficiency.
Big Data: A Parallel Particle Swarm Optimization-Back-Propagation Neural Network Algorithm Based on MapReduce.

PubMed

Cao, Jianfang; Cui, Hongyan; Shi, Hao; Jiao, Lijuan

2016-01-01

A back-propagation (BP) neural network can solve complicated random nonlinear mapping problems; therefore, it can be applied to a wide range of problems. However, as the sample size increases, the time required to train BP neural networks becomes lengthy. Moreover, the classification accuracy decreases as well. To improve the classification accuracy and runtime efficiency of the BP neural network algorithm, we proposed a parallel design and realization method for a particle swarm optimization (PSO)-optimized BP neural network based on MapReduce on the Hadoop platform using both the PSO algorithm and a parallel design. The PSO algorithm was used to optimize the BP neural network's initial weights and thresholds and improve the accuracy of the classification algorithm. The MapReduce parallel programming model was utilized to achieve parallel processing of the BP algorithm, thereby solving the problems of hardware and communication overhead when the BP neural network addresses big data. Datasets on 5 different scales were constructed using the scene image library from the SUN Database. The classification accuracy of the parallel PSO-BP neural network algorithm is approximately 92%, and the system efficiency is approximately 0.85, which presents obvious advantages when processing big data. The algorithm proposed in this study demonstrated both higher classification accuracy and improved time efficiency, which represents a significant improvement obtained from applying parallel processing to an intelligent algorithm on big data.
A Genetic Algorithm That Exchanges Neighboring Centers for Fuzzy c-Means Clustering

ERIC Educational Resources Information Center

Chahine, Firas Safwan

2012-01-01

Clustering algorithms are widely used in pattern recognition and data mining applications. Due to their computational efficiency, partitional clustering algorithms are better suited for applications with large datasets than hierarchical clustering algorithms. K-means is among the most popular partitional clustering algorithm, but has a major…
Utilizing Online Training for Child Sexual Abuse Prevention: Benefits and Limitations

ERIC Educational Resources Information Center

Paranal, Rechelle; Thomas, Kiona Washington; Derrick, Christina

2012-01-01

The prevalence of child sexual abuse demands innovative approaches to prevent further victimization. The online environment provides new opportunities to expand existing child sexual abuse prevention trainings that target adult gatekeepers and allow for large scale interventions that are fiscally viable. This article discusses the benefits and…
Learning in the Beat: What Influences Environmental Journalists' Perception of Knowledge?

ERIC Educational Resources Information Center

Takahashi, Bruno; Tandoc, Edson C., Jr.

2013-01-01

We conducted a survey of environmental journalists in the United States to explore individual, routine, and organizational influences on perceived knowledge of environmental issues. Using the gatekeeping theory, we found that routine and organizational factors, such as orientation to particular sources and affiliation to an organization, predict…
What Turns Events into News?

ERIC Educational Resources Information Center

Tukachinsky, Riva

2013-01-01

"The New York Times" is known for its slogan ''All the News That's Fit to Print.'' But how do gatekeepers decide which events meet this criterion? Although some individuals might believe that the news constitutes an undistorted reflection of the social reality, students in communication courses have the…
MSW Programs: Gatekeepers to the Field of Developmental Disabilities

ERIC Educational Resources Information Center

Russo-Gleicher, Rosalie J.

2008-01-01

This article presents qualitative insights into the roles of master of social work programs in developing student practice interests in working with people with developmental disabilities (DD). Semistructured in-depth interviews were conducted with 24 MSW social workers practicing in the field of DD in the northeastern United States. Participants…
Marketing Academics' Perceptions of the Peer Review Process

ERIC Educational Resources Information Center

Bailey, Charles D.; Hair, Joe F.; Hermanson, Dana R.; Crittenden, Victoria L.

2012-01-01

Publication in refereed journals is critical to career success for most marketing faculty members, and the peer review process is the gatekeeper for a refereed journal. The study reported here examines marketing academics' perceptions of this peer review process. Based on responses from 653 marketing academics, we find favorable overall…
Is the Sky Falling? Grade Inflation and the Signaling Power of Grades

ERIC Educational Resources Information Center

Pattison, Evangeleen; Grodsky, Eric; Muller, Chandra

2013-01-01

Grades are the fundamental currency of our educational system; they signal academic achievement and noncognitive skills to parents, employers, postsecondary gatekeepers, and students themselves. Grade inflation compromises the signaling value of grades and undermines their capacity to achieve the functions for which they are intended. We challenge…
Projecting Project Management's Future within the Academic Landscape

ERIC Educational Resources Information Center

Halfond, Jay A.

2011-01-01

U.S. universities have had century-long success in absorbing existing professions into their curricula--by making academe their gatekeeper. These professions often started with apprenticeships and short training courses leading to a certification examination--and were then elevated and "academized" into a comprehensive body of knowledge,…
New Pathways to Credentialing: The Digital Badge

ERIC Educational Resources Information Center

DiSalvio, Philip

2016-01-01

With an increasing number of higher education institutions now offering "digital badges," some suggest that this credential has become a practical commodity in the world of college credentials. Colleges and universities are in a unique position to be the gatekeepers of many of those credentials. Among the many institutions of higher…
The Gatekeepers of Business Education Research: An Institutional Analysis

ERIC Educational Resources Information Center

Urbancic, Frank R.

2011-01-01

The author ranked the academic standing of universities based on faculty representation to the editorial boards of business education journals. Previous studies that ranked institutions for editorial board representation focused on journals that primarily favor publication of basic and applied research contributions. As a result, prior research…
K-8 Teachers' Self-Efficacy Beliefs for Teaching Mathematics

ERIC Educational Resources Information Center

Amankonah, Frank O.

2013-01-01

Mathematics knowledge and skills serve as the "gatekeeper" to students' choice of college majors, success obtaining college degrees, and entry into the workforce. However, on the mathematics portion of standardized tests, U.S. fourth and eighth graders performed below their peers in countries such as Singapore, Hong Kong, China, and…
Researchers at the Gate: Factors Influencing Districts' Right of Entry Decisions

ERIC Educational Resources Information Center

Melnick, Steven A.; Henk, William A.

2006-01-01

Background: The No Child Left Behind legislation creates an increased need for new school-based empirical studies whose implementation will depend largely on researchers' access to various school populations and records. Access decisions are typically made by superintendents, or their designees, functioning as gatekeepers who control right of…
Outcomes of a Suicide Prevention Gatekeeper Training on a University Campus

ERIC Educational Resources Information Center

Indelicato, Natalie Arce; Mirsu-Paun, Anca; Griffin, Wayne D.

2011-01-01

A university-wide suicide prevention program was implemented to provide students, faculty, and staff tools to identify, assist, and refer distressed and suicidal individuals. The study examined participant self-reports of suicide-related knowledge and prevention skills, group differences in suicide prevention knowledge and skills, group…
Postpartum Obesity: The Root Problem of Childhood Obesity?

ERIC Educational Resources Information Center

Keen, Valencia Browning; Potts, Claudia Sealey

2011-01-01

Remedying childhood obesity cannot take place without first identifying relevant issues commonly influencing gatekeepers of food for children as well as the role modeling for encouraging or discouraging daily activities. Children cannot drive to the store, form grocery lists or complete menu management tasks without adult assistance. Excessive…

Occluded Academic Genres: An Analysis of the MBA Thought Essay

ERIC Educational Resources Information Center

Loudermilk, Brandon Conner

2007-01-01

Several strands of research in applied linguistics have increasingly focused their attention on the application of genre theory to the classroom. In advanced academics, the genres of disciplinary communities serve gate-keeping functions that students must negotiate in order to succeed in their academic endeavors. Often without explicit…
Community College Developmental Education Students' Understanding of Foundational Fraction Concepts

ERIC Educational Resources Information Center

Alexander, Cathleen Marie

2013-01-01

Mathematics, in general, and algebra courses, in particular, have been categorized as "gatekeepers" for higher education, better jobs, and even citizenship. For many low-income and working adults, community college is the institution where they choose to develop their mathematics understanding so they can pursue their dreams.…
Chronicle of Higher Education. Volume 50, Number 43, July 2, 2004

ERIC Educational Resources Information Center

Chronicle of Higher Education, 2004

2004-01-01

"Chronicle of Higher Education" presents an abundant source of news and information for college and university faculty members and administrators. This July 2, 2004 issue of "Chronicle of Higher Education" includes the following articles: (1) "The Provost as Gatekeeper: A Former Provost Offers Advice on Managing the…
Barriers to Community Participation in Development Planning: Lessons from the Mutengene (Cameroon) Self-Help Water Project.

ERIC Educational Resources Information Center

Njoh, Ambe J.

2002-01-01

A community water supply project in Cameroon illustrates the following constraints on community participation in development: paternalistic authorities, prescriptive role of the state, selective participation, bias toward "hard" issues, inattention to negative results, group conflicts, gatekeeping, pressure for immediate results,…
Strategies low-income parents use to overcome their children's food refusal

USDA-ARS?s Scientific Manuscript database

Parents play a key role in the development of eating habits in preschool children, as they are the food "gatekeepers". Repeated exposure to new foods can improve child food preferences and consumption. The objective of this study was to determine parent feeding strategies used to influence child acc...
Gatekeeper or Lynchpin? The Role of the Principal in School-University Partnerships

ERIC Educational Resources Information Center

Nettleton, Kimberely Fletcher; Barnett, David

2016-01-01

Teacher education programs are always evolving. To provide opportunities for pre-service teachers to combine pedagogy with practical experience, many programs are developing school-university partnerships. The pairing of pre-service teachers with experienced mentor teachers offers enriched field experience opportunities. The effect of the…
Connections: A Journal of Adult Literacy. Volume IV.

ERIC Educational Resources Information Center

Connections: A Journal of Adult Literacy, 1991

1991-01-01

This journal provides a forum for adult educators to express their ideas on adult literacy. The following articles are included: "Teaching Moments: Teaching People, Not Lessons" (Patricia Wild); "Whole Language: Implications for the Adult Learner" (Jeri Gillin); "Gatekeepers or Advocates?" (Rosie Wickert); "Writing with Teen Mothers: I Have…
Fractions: Could They Really Be the Gatekeeper's Doorman?

ERIC Educational Resources Information Center

Booth, Julie L.; Newton, Kristie J.

2012-01-01

The National Mathematics Advisory Panel (NMAP, 2008) asserts that a foundational knowledge of fractions is crucial for students' success in algebra; however, empirical evidence for this claim is relatively nonexistent. In the present study, we examine the impact of middle school students' fraction and whole number magnitude knowledge on various…
Identifying Opinion Leaders to Promote Behavior Change

ERIC Educational Resources Information Center

Valente, Thomas W.; Pumpuang, Patchareeya

2007-01-01

This article reviews 10 techniques used to identify opinion leaders to promote behavior change. Opinion leaders can act as gatekeepers for interventions, help change social norms, and accelerate behavior change. Few studies document the manner in which opinion leaders are identified, recruited, and trained to promote health. The authors categorize…
Banking on Child Nutrition.

ERIC Educational Resources Information Center

Briley, Margaret; McBride, Andrea M.; Roberts-Gray, Cynthia

1997-01-01

The child-care facility is rapidly growing into the role of gatekeeper on food intake for children. This article describes guidelines for children's nutritional needs, what children are actually eating, how to make menus more nutritious (including recipes), how to strengthen menus and keep food costs low, and the use of food banks. (EV)
Counselor Educators and Students with Problems of Professional Competence: A Survey and Discussion

ERIC Educational Resources Information Center

Brown-Rice, Kathleen; Furr, Susan

2016-01-01

A total of 370 counselor educators in CACREP-accredited [Council for Accreditation of Counseling and Related Educational Programs] programs were surveyed to determine their knowledge of master's students' problems of professional competence (PPC) and their perception of roadblocks that affect gatekeeping practices. Findings suggest that educators…
The Great Bug Hunt 2011

ERIC Educational Resources Information Center

Dixon-Watmough, Rebecca

2011-01-01

The Association For Science Education's "schoolscience.co.uk Great Bug Hunt 2011," in association with Martin Rapley and Gatekeeper Educational, has been a resounding success--not only because it fits into the science curriculum so neatly, but also because of the passion it evoked in the children who took part. This year's entries were…
Youth Suicide: The Knowledge and Attitudes of Australian Teachers and Clergy.

ERIC Educational Resources Information Center

Leane, Wendy; Shute, Rosalyn

1998-01-01

Professional groups identified as "gatekeepers" who might serve as first line of assistance for distressed young people were surveyed (N=219). Low levels of knowledge about suicide risk were found. Educational efforts directed at risk identification and prevention, attitudinal issues, and communication with young suicidal people are…
A Culturally Responsive Intervention for Addressing Problematic Behaviors in Counseling Students

ERIC Educational Resources Information Center

Goodrich, Kristopher M.; Shin, Richard Q.

2013-01-01

Counseling faculty serve as gatekeepers to protect the public from trainees who demonstrate significant deficiencies in professional functioning. Two issues that have not been thoroughly examined are how different cultural values may intersect with the assessment of appropriate professional competencies and whether the multicultural environment of…
Counselor Educators' Gatekeeping Responsibilities and Students' First Amendment Rights

ERIC Educational Resources Information Center

Hutchens, Neal; Block, Jason; Young, Marianne

2013-01-01

In 2 recent legal cases, graduate counselor education students challenged the imposition of remediation plans as violating their First Amendment rights of freedom of speech and religion. With special emphasis on this recent litigation, the article examines the legal standards governing the authority of counselor educators at public colleges and…
The Composition of the Editorial Boards of General Marketing Journals

ERIC Educational Resources Information Center

Pan, Yue; Zhang, Jason Q.

2014-01-01

Unlike the diversity issues in corporate governance, the diversity in top academic positions (e.g., editorial boards of academic journals in business) is rather underresearched. The editorial boards of academic marketing journals are important gatekeepers and trendsetters in the creation and dissemination of marketing knowledge. Membership on…
Attention Performance in Young Adults with Learning Disabilities

ERIC Educational Resources Information Center

Sterr, Annette M.

2004-01-01

Attention acts as the mind's "gatekeeper" by regulating and prioritizing the stimuli processed by the central nervous system. It is essential for cognitive performance, memory, and behavior, and we know that even slight deficiencies in attention compromise learning. Basic neuroscience research further indicates that attention consists of (fairly)…
Transnational Mobility and International Academic Employment: Gatekeeping in an Academic Competition Arena

ERIC Educational Resources Information Center

Cantwell, Brendan

2011-01-01

This article draws upon concepts developed in recent empirical and theoretical work on high skilled and academic mobility and migration including accidental mobility, forced mobility and negotiated mobility. These concepts inform a situated, qualitative study of mobility among international postdoctoral researchers in life sciences and engineering…
Efficient Record Linkage Algorithms Using Complete Linkage Clustering.

PubMed

Mamun, Abdullah-Al; Aseltine, Robert; Rajasekaran, Sanguthevar

2016-01-01

Data from different agencies share data of the same individuals. Linking these datasets to identify all the records belonging to the same individuals is a crucial and challenging problem, especially given the large volumes of data. A large number of available algorithms for record linkage are prone to either time inefficiency or low-accuracy in finding matches and non-matches among the records. In this paper we propose efficient as well as reliable sequential and parallel algorithms for the record linkage problem employing hierarchical clustering methods. We employ complete linkage hierarchical clustering algorithms to address this problem. In addition to hierarchical clustering, we also use two other techniques: elimination of duplicate records and blocking. Our algorithms use sorting as a sub-routine to identify identical copies of records. We have tested our algorithms on datasets with millions of synthetic records. Experimental results show that our algorithms achieve nearly 100% accuracy. Parallel implementations achieve almost linear speedups. Time complexities of these algorithms do not exceed those of previous best-known algorithms. Our proposed algorithms outperform previous best-known algorithms in terms of accuracy consuming reasonable run times.
Efficient Record Linkage Algorithms Using Complete Linkage Clustering

PubMed Central

Mamun, Abdullah-Al; Aseltine, Robert; Rajasekaran, Sanguthevar

2016-01-01

Data from different agencies share data of the same individuals. Linking these datasets to identify all the records belonging to the same individuals is a crucial and challenging problem, especially given the large volumes of data. A large number of available algorithms for record linkage are prone to either time inefficiency or low-accuracy in finding matches and non-matches among the records. In this paper we propose efficient as well as reliable sequential and parallel algorithms for the record linkage problem employing hierarchical clustering methods. We employ complete linkage hierarchical clustering algorithms to address this problem. In addition to hierarchical clustering, we also use two other techniques: elimination of duplicate records and blocking. Our algorithms use sorting as a sub-routine to identify identical copies of records. We have tested our algorithms on datasets with millions of synthetic records. Experimental results show that our algorithms achieve nearly 100% accuracy. Parallel implementations achieve almost linear speedups. Time complexities of these algorithms do not exceed those of previous best-known algorithms. Our proposed algorithms outperform previous best-known algorithms in terms of accuracy consuming reasonable run times. PMID:27124604

SPHINX--an algorithm for taxonomic binning of metagenomic sequences.

PubMed

Mohammed, Monzoorul Haque; Ghosh, Tarini Shankar; Singh, Nitin Kumar; Mande, Sharmila S

2011-01-01

Compared with composition-based binning algorithms, the binning accuracy and specificity of alignment-based binning algorithms is significantly higher. However, being alignment-based, the latter class of algorithms require enormous amount of time and computing resources for binning huge metagenomic datasets. The motivation was to develop a binning approach that can analyze metagenomic datasets as rapidly as composition-based approaches, but nevertheless has the accuracy and specificity of alignment-based algorithms. This article describes a hybrid binning approach (SPHINX) that achieves high binning efficiency by utilizing the principles of both 'composition'- and 'alignment'-based binning algorithms. Validation results with simulated sequence datasets indicate that SPHINX is able to analyze metagenomic sequences as rapidly as composition-based algorithms. Furthermore, the binning efficiency (in terms of accuracy and specificity of assignments) of SPHINX is observed to be comparable with results obtained using alignment-based algorithms. A web server for the SPHINX algorithm is available at http://metagenomics.atc.tcs.com/SPHINX/.
A Novel Hybrid Firefly Algorithm for Global Optimization.

PubMed

Zhang, Lina; Liu, Liqiang; Yang, Xin-She; Dai, Yuntao

Global optimization is challenging to solve due to its nonlinearity and multimodality. Traditional algorithms such as the gradient-based methods often struggle to deal with such problems and one of the current trends is to use metaheuristic algorithms. In this paper, a novel hybrid population-based global optimization algorithm, called hybrid firefly algorithm (HFA), is proposed by combining the advantages of both the firefly algorithm (FA) and differential evolution (DE). FA and DE are executed in parallel to promote information sharing among the population and thus enhance searching efficiency. In order to evaluate the performance and efficiency of the proposed algorithm, a diverse set of selected benchmark functions are employed and these functions fall into two groups: unimodal and multimodal. The experimental results show better performance of the proposed algorithm compared to the original version of the firefly algorithm (FA), differential evolution (DE) and particle swarm optimization (PSO) in the sense of avoiding local minima and increasing the convergence rate.
A Novel Hybrid Firefly Algorithm for Global Optimization

PubMed Central

Zhang, Lina; Liu, Liqiang; Yang, Xin-She; Dai, Yuntao

2016-01-01

Global optimization is challenging to solve due to its nonlinearity and multimodality. Traditional algorithms such as the gradient-based methods often struggle to deal with such problems and one of the current trends is to use metaheuristic algorithms. In this paper, a novel hybrid population-based global optimization algorithm, called hybrid firefly algorithm (HFA), is proposed by combining the advantages of both the firefly algorithm (FA) and differential evolution (DE). FA and DE are executed in parallel to promote information sharing among the population and thus enhance searching efficiency. In order to evaluate the performance and efficiency of the proposed algorithm, a diverse set of selected benchmark functions are employed and these functions fall into two groups: unimodal and multimodal. The experimental results show better performance of the proposed algorithm compared to the original version of the firefly algorithm (FA), differential evolution (DE) and particle swarm optimization (PSO) in the sense of avoiding local minima and increasing the convergence rate. PMID:27685869
Approximation Algorithms for Multicommodity Flow and Shop Scheduling Problems

DTIC Science & Technology

1992-09-01

DARPA N00014-89-J-1988 11. SUPPLEMENTARY NOTES Ŗa. oIs7RIBU ric.c / AVAILAaILITY STATEMENT, 1.2. 3ISTRIBUT;CN C:. E In this thesis , we give efficient...University Thesis Supervisor Accepted by Campbell L. Searle Chairman, Departmental Committee on Graduate Students Approximation Algorithms for Multicommodity...partial fulfillment of the requirements for the degree of Doctor of Philosophy Abstract In this thesis , we give efficient approximation algorithms for
Efficient Training of Supervised Spiking Neural Network via Accurate Synaptic-Efficiency Adjustment Method.

PubMed

Xie, Xiurui; Qu, Hong; Yi, Zhang; Kurths, Jurgen

2017-06-01

The spiking neural network (SNN) is the third generation of neural networks and performs remarkably well in cognitive tasks, such as pattern recognition. The temporal neural encode mechanism found in biological hippocampus enables SNN to possess more powerful computation capability than networks with other encoding schemes. However, this temporal encoding approach requires neurons to process information serially on time, which reduces learning efficiency significantly. To keep the powerful computation capability of the temporal encoding mechanism and to overcome its low efficiency in the training of SNNs, a new training algorithm, the accurate synaptic-efficiency adjustment method is proposed in this paper. Inspired by the selective attention mechanism of the primate visual system, our algorithm selects only the target spike time as attention areas, and ignores voltage states of the untarget ones, resulting in a significant reduction of training time. Besides, our algorithm employs a cost function based on the voltage difference between the potential of the output neuron and the firing threshold of the SNN, instead of the traditional precise firing time distance. A normalized spike-timing-dependent-plasticity learning window is applied to assigning this error to different synapses for instructing their training. Comprehensive simulations are conducted to investigate the learning properties of our algorithm, with input neurons emitting both single spike and multiple spikes. Simulation results indicate that our algorithm possesses higher learning performance than the existing other methods and achieves the state-of-the-art efficiency in the training of SNN.
Efficiency in nonequilibrium molecular dynamics Monte Carlo simulations

DOE PAGES

Radak, Brian K.; Roux, Benoît

2016-10-07

Hybrid algorithms combining nonequilibrium molecular dynamics and Monte Carlo (neMD/MC) offer a powerful avenue for improving the sampling efficiency of computer simulations of complex systems. These neMD/MC algorithms are also increasingly finding use in applications where conventional approaches are impractical, such as constant-pH simulations with explicit solvent. However, selecting an optimal nonequilibrium protocol for maximum efficiency often represents a non-trivial challenge. This work evaluates the efficiency of a broad class of neMD/MC algorithms and protocols within the theoretical framework of linear response theory. The approximations are validated against constant pH-MD simulations and shown to provide accurate predictions of neMD/MC performance.more » An assessment of a large set of protocols confirms (both theoretically and empirically) that a linear work protocol gives the best neMD/MC performance. Lastly, a well-defined criterion for optimizing the time parameters of the protocol is proposed and demonstrated with an adaptive algorithm that improves the performance on-the-fly with minimal cost.« less
Compound Event Barrier Coverage in Wireless Sensor Networks under Multi-Constraint Conditions.

PubMed

Zhuang, Yaoming; Wu, Chengdong; Zhang, Yunzhou; Jia, Zixi

2016-12-24

It is important to monitor compound event by barrier coverage issues in wireless sensor networks (WSNs). Compound event barrier coverage (CEBC) is a novel coverage problem. Unlike traditional ones, the data of compound event barrier coverage comes from different types of sensors. It will be subject to multiple constraints under complex conditions in real-world applications. The main objective of this paper is to design an efficient algorithm for complex conditions that can combine the compound event confidence. Moreover, a multiplier method based on an active-set strategy (ASMP) is proposed to optimize the multiple constraints in compound event barrier coverage. The algorithm can calculate the coverage ratio efficiently and allocate the sensor resources reasonably in compound event barrier coverage. The proposed algorithm can simplify complex problems to reduce the computational load of the network and improve the network efficiency. The simulation results demonstrate that the proposed algorithm is more effective and efficient than existing methods, especially in the allocation of sensor resources.
Compound Event Barrier Coverage in Wireless Sensor Networks under Multi-Constraint Conditions

PubMed Central

Zhuang, Yaoming; Wu, Chengdong; Zhang, Yunzhou; Jia, Zixi

2016-01-01

It is important to monitor compound event by barrier coverage issues in wireless sensor networks (WSNs). Compound event barrier coverage (CEBC) is a novel coverage problem. Unlike traditional ones, the data of compound event barrier coverage comes from different types of sensors. It will be subject to multiple constraints under complex conditions in real-world applications. The main objective of this paper is to design an efficient algorithm for complex conditions that can combine the compound event confidence. Moreover, a multiplier method based on an active-set strategy (ASMP) is proposed to optimize the multiple constraints in compound event barrier coverage. The algorithm can calculate the coverage ratio efficiently and allocate the sensor resources reasonably in compound event barrier coverage. The proposed algorithm can simplify complex problems to reduce the computational load of the network and improve the network efficiency. The simulation results demonstrate that the proposed algorithm is more effective and efficient than existing methods, especially in the allocation of sensor resources. PMID:28029118
Efficient Multiple Kernel Learning Algorithms Using Low-Rank Representation.

PubMed

Niu, Wenjia; Xia, Kewen; Zu, Baokai; Bai, Jianchuan

2017-01-01

Unlike Support Vector Machine (SVM), Multiple Kernel Learning (MKL) allows datasets to be free to choose the useful kernels based on their distribution characteristics rather than a precise one. It has been shown in the literature that MKL holds superior recognition accuracy compared with SVM, however, at the expense of time consuming computations. This creates analytical and computational difficulties in solving MKL algorithms. To overcome this issue, we first develop a novel kernel approximation approach for MKL and then propose an efficient Low-Rank MKL (LR-MKL) algorithm by using the Low-Rank Representation (LRR). It is well-acknowledged that LRR can reduce dimension while retaining the data features under a global low-rank constraint. Furthermore, we redesign the binary-class MKL as the multiclass MKL based on pairwise strategy. Finally, the recognition effect and efficiency of LR-MKL are verified on the datasets Yale, ORL, LSVT, and Digit. Experimental results show that the proposed LR-MKL algorithm is an efficient kernel weights allocation method in MKL and boosts the performance of MKL largely.
SymDex: increasing the efficiency of chemical fingerprint similarity searches for comparing large chemical libraries by using query set indexing.

PubMed

Tai, David; Fang, Jianwen

2012-08-27

The large sizes of today's chemical databases require efficient algorithms to perform similarity searches. It can be very time consuming to compare two large chemical databases. This paper seeks to build upon existing research efforts by describing a novel strategy for accelerating existing search algorithms for comparing large chemical collections. The quest for efficiency has focused on developing better indexing algorithms by creating heuristics for searching individual chemical against a chemical library by detecting and eliminating needless similarity calculations. For comparing two chemical collections, these algorithms simply execute searches for each chemical in the query set sequentially. The strategy presented in this paper achieves a speedup upon these algorithms by indexing the set of all query chemicals so redundant calculations that arise in the case of sequential searches are eliminated. We implement this novel algorithm by developing a similarity search program called Symmetric inDexing or SymDex. SymDex shows over a 232% maximum speedup compared to the state-of-the-art single query search algorithm over real data for various fingerprint lengths. Considerable speedup is even seen for batch searches where query set sizes are relatively small compared to typical database sizes. To the best of our knowledge, SymDex is the first search algorithm designed specifically for comparing chemical libraries. It can be adapted to most, if not all, existing indexing algorithms and shows potential for accelerating future similarity search algorithms for comparing chemical databases.
Trellises and Trellis-Based Decoding Algorithms for Linear Block Codes. Part 3

NASA Technical Reports Server (NTRS)

Lin, Shu

1998-01-01

Decoding algorithms based on the trellis representation of a code (block or convolutional) drastically reduce decoding complexity. The best known and most commonly used trellis-based decoding algorithm is the Viterbi algorithm. It is a maximum likelihood decoding algorithm. Convolutional codes with the Viterbi decoding have been widely used for error control in digital communications over the last two decades. This chapter is concerned with the application of the Viterbi decoding algorithm to linear block codes. First, the Viterbi algorithm is presented. Then, optimum sectionalization of a trellis to minimize the computational complexity of a Viterbi decoder is discussed and an algorithm is presented. Some design issues for IC (integrated circuit) implementation of a Viterbi decoder are considered and discussed. Finally, a new decoding algorithm based on the principle of compare-select-add is presented. This new algorithm can be applied to both block and convolutional codes and is more efficient than the conventional Viterbi algorithm based on the add-compare-select principle. This algorithm is particularly efficient for rate 1/n antipodal convolutional codes and their high-rate punctured codes. It reduces computational complexity by one-third compared with the Viterbi algorithm.
CONEDEP: COnvolutional Neural network based Earthquake DEtection and Phase Picking

NASA Astrophysics Data System (ADS)

Zhou, Y.; Huang, Y.; Yue, H.; Zhou, S.; An, S.; Yun, N.

2017-12-01

We developed an automatic local earthquake detection and phase picking algorithm based on Fully Convolutional Neural network (FCN). The FCN algorithm detects and segments certain features (phases) in 3 component seismograms to realize efficient picking. We use STA/LTA algorithm and template matching algorithm to construct the training set from seismograms recorded 1 month before and after the Wenchuan earthquake. Precise P and S phases are identified and labeled to construct the training set. Noise data are produced by combining back-ground noise and artificial synthetic noise to form the equivalent scale of noise set as the signal set. Training is performed on GPUs to achieve efficient convergence. Our algorithm has significantly improved performance in terms of the detection rate and precision in comparison with STA/LTA and template matching algorithms.
A Double-function Digital Watermarking Algorithm Based on Chaotic System and LWT

NASA Astrophysics Data System (ADS)

Yuxia, Zhao; Jingbo, Fan

A double- function digital watermarking technology is studied and a double-function digital watermarking algorithm of colored image is presented based on chaotic system and the lifting wavelet transformation (LWT).The algorithm has realized the double aims of the copyright protection and the integrity authentication of image content. Making use of feature of human visual system (HVS), the watermark image is embedded into the color image's low frequency component and middle frequency components by different means. The algorithm has great security by using two kinds chaotic mappings and Arnold to scramble the watermark image at the same time. The algorithm has good efficiency by using LWT. The emulation experiment indicates the algorithm has great efficiency and security, and the effect of concealing is really good.
An efficient dictionary learning algorithm and its application to 3-D medical image denoising.

PubMed

Li, Shutao; Fang, Leyuan; Yin, Haitao

2012-02-01

In this paper, we propose an efficient dictionary learning algorithm for sparse representation of given data and suggest a way to apply this algorithm to 3-D medical image denoising. Our learning approach is composed of two main parts: sparse coding and dictionary updating. On the sparse coding stage, an efficient algorithm named multiple clusters pursuit (MCP) is proposed. The MCP first applies a dictionary structuring strategy to cluster the atoms with high coherence together, and then employs a multiple-selection strategy to select several competitive atoms at each iteration. These two strategies can greatly reduce the computation complexity of the MCP and assist it to obtain better sparse solution. On the dictionary updating stage, the alternating optimization that efficiently approximates the singular value decomposition is introduced. Furthermore, in the 3-D medical image denoising application, a joint 3-D operation is proposed for taking the learning capabilities of the presented algorithm to simultaneously capture the correlations within each slice and correlations across the nearby slices, thereby obtaining better denoising results. The experiments on both synthetically generated data and real 3-D medical images demonstrate that the proposed approach has superior performance compared to some well-known methods. © 2011 IEEE
Efficient Retrieval of Massive Ocean Remote Sensing Images via a Cloud-Based Mean-Shift Algorithm.

PubMed

Yang, Mengzhao; Song, Wei; Mei, Haibin

2017-07-23

The rapid development of remote sensing (RS) technology has resulted in the proliferation of high-resolution images. There are challenges involved in not only storing large volumes of RS images but also in rapidly retrieving the images for ocean disaster analysis such as for storm surges and typhoon warnings. In this paper, we present an efficient retrieval of massive ocean RS images via a Cloud-based mean-shift algorithm. Distributed construction method via the pyramid model is proposed based on the maximum hierarchical layer algorithm and used to realize efficient storage structure of RS images on the Cloud platform. We achieve high-performance processing of massive RS images in the Hadoop system. Based on the pyramid Hadoop distributed file system (HDFS) storage method, an improved mean-shift algorithm for RS image retrieval is presented by fusion with the canopy algorithm via Hadoop MapReduce programming. The results show that the new method can achieve better performance for data storage than HDFS alone and WebGIS-based HDFS. Speedup and scaleup are very close to linear changes with an increase of RS images, which proves that image retrieval using our method is efficient.
EDDA: An Efficient Distributed Data Replication Algorithm in VANETs.

PubMed

Zhu, Junyu; Huang, Chuanhe; Fan, Xiying; Guo, Sipei; Fu, Bin

2018-02-10

Efficient data dissemination in vehicular ad hoc networks (VANETs) is a challenging issue due to the dynamic nature of the network. To improve the performance of data dissemination, we study distributed data replication algorithms in VANETs for exchanging information and computing in an arbitrarily-connected network of vehicle nodes. To achieve low dissemination delay and improve the network performance, we control the number of message copies that can be disseminated in the network and then propose an efficient distributed data replication algorithm (EDDA). The key idea is to let the data carrier distribute the data dissemination tasks to multiple nodes to speed up the dissemination process. We calculate the number of communication stages for the network to enter into a balanced status and show that the proposed distributed algorithm can converge to a consensus in a small number of communication stages. Most of the theoretical results described in this paper are to study the complexity of network convergence. The lower bound and upper bound are also provided in the analysis of the algorithm. Simulation results show that the proposed EDDA can efficiently disseminate messages to vehicles in a specific area with low dissemination delay and system overhead.
EDDA: An Efficient Distributed Data Replication Algorithm in VANETs

PubMed Central

Zhu, Junyu; Huang, Chuanhe; Fan, Xiying; Guo, Sipei; Fu, Bin

2018-01-01

Efficient data dissemination in vehicular ad hoc networks (VANETs) is a challenging issue due to the dynamic nature of the network. To improve the performance of data dissemination, we study distributed data replication algorithms in VANETs for exchanging information and computing in an arbitrarily-connected network of vehicle nodes. To achieve low dissemination delay and improve the network performance, we control the number of message copies that can be disseminated in the network and then propose an efficient distributed data replication algorithm (EDDA). The key idea is to let the data carrier distribute the data dissemination tasks to multiple nodes to speed up the dissemination process. We calculate the number of communication stages for the network to enter into a balanced status and show that the proposed distributed algorithm can converge to a consensus in a small number of communication stages. Most of the theoretical results described in this paper are to study the complexity of network convergence. The lower bound and upper bound are also provided in the analysis of the algorithm. Simulation results show that the proposed EDDA can efficiently disseminate messages to vehicles in a specific area with low dissemination delay and system overhead. PMID:29439443
DANoC: An Efficient Algorithm and Hardware Codesign of Deep Neural Networks on Chip.

PubMed

Zhou, Xichuan; Li, Shengli; Tang, Fang; Hu, Shengdong; Lin, Zhi; Zhang, Lei

2017-07-18

Deep neural networks (NNs) are the state-of-the-art models for understanding the content of images and videos. However, implementing deep NNs in embedded systems is a challenging task, e.g., a typical deep belief network could exhaust gigabytes of memory and result in bandwidth and computational bottlenecks. To address this challenge, this paper presents an algorithm and hardware codesign for efficient deep neural computation. A hardware-oriented deep learning algorithm, named the deep adaptive network, is proposed to explore the sparsity of neural connections. By adaptively removing the majority of neural connections and robustly representing the reserved connections using binary integers, the proposed algorithm could save up to 99.9% memory utility and computational resources without undermining classification accuracy. An efficient sparse-mapping-memory-based hardware architecture is proposed to fully take advantage of the algorithmic optimization. Different from traditional Von Neumann architecture, the deep-adaptive network on chip (DANoC) brings communication and computation in close proximity to avoid power-hungry parameter transfers between on-board memory and on-chip computational units. Experiments over different image classification benchmarks show that the DANoC system achieves competitively high accuracy and efficiency comparing with the state-of-the-art approaches.
Efficient Retrieval of Massive Ocean Remote Sensing Images via a Cloud-Based Mean-Shift Algorithm

PubMed Central

Song, Wei; Mei, Haibin

2017-01-01

The rapid development of remote sensing (RS) technology has resulted in the proliferation of high-resolution images. There are challenges involved in not only storing large volumes of RS images but also in rapidly retrieving the images for ocean disaster analysis such as for storm surges and typhoon warnings. In this paper, we present an efficient retrieval of massive ocean RS images via a Cloud-based mean-shift algorithm. Distributed construction method via the pyramid model is proposed based on the maximum hierarchical layer algorithm and used to realize efficient storage structure of RS images on the Cloud platform. We achieve high-performance processing of massive RS images in the Hadoop system. Based on the pyramid Hadoop distributed file system (HDFS) storage method, an improved mean-shift algorithm for RS image retrieval is presented by fusion with the canopy algorithm via Hadoop MapReduce programming. The results show that the new method can achieve better performance for data storage than HDFS alone and WebGIS-based HDFS. Speedup and scaleup are very close to linear changes with an increase of RS images, which proves that image retrieval using our method is efficient. PMID:28737699
Energy-efficient algorithm for classification of states of wireless sensor network using machine learning methods

NASA Astrophysics Data System (ADS)

Yuldashev, M. N.; Vlasov, A. I.; Novikov, A. N.

2018-05-01

This paper focuses on the development of an energy-efficient algorithm for classification of states of a wireless sensor network using machine learning methods. The proposed algorithm reduces energy consumption by: 1) elimination of monitoring of parameters that do not affect the state of the sensor network, 2) reduction of communication sessions over the network (the data are transmitted only if their values can affect the state of the sensor network). The studies of the proposed algorithm have shown that at classification accuracy close to 100%, the number of communication sessions can be reduced by 80%.

An efficient parallel algorithm for the solution of a tridiagonal linear system of equations

NASA Technical Reports Server (NTRS)

Stone, H. S.

1971-01-01

Tridiagonal linear systems of equations are solved on conventional serial machines in a time proportional to N, where N is the number of equations. The conventional algorithms do not lend themselves directly to parallel computations on computers of the ILLIAC IV class, in the sense that they appear to be inherently serial. An efficient parallel algorithm is presented in which computation time grows as log sub 2 N. The algorithm is based on recursive doubling solutions of linear recurrence relations, and can be used to solve recurrence relations of all orders.
Efficient dynamic simulation for multiple chain robotic mechanisms

NASA Technical Reports Server (NTRS)

Lilly, Kathryn W.; Orin, David E.

1989-01-01

An efficient O(mN) algorithm for dynamic simulation of simple closed-chain robotic mechanisms is presented, where m is the number of chains, and N is the number of degrees of freedom for each chain. It is based on computation of the operational space inertia matrix (6 x 6) for each chain as seen by the body, load, or object. Also, computation of the chain dynamics, when opened at one end, is required, and the most efficient algorithm is used for this purpose. Parallel implementation of the dynamics for each chain results in an O(N) + O(log sub 2 m+1) algorithm.
Exploration of depth modeling mode one lossless wedgelets storage strategies for 3D-high efficiency video coding

NASA Astrophysics Data System (ADS)

Sanchez, Gustavo; Marcon, César; Agostini, Luciano Volcan

2018-01-01

The 3D-high efficiency video coding has introduced tools to obtain higher efficiency in 3-D video coding, and most of them are related to the depth maps coding. Among these tools, the depth modeling mode-1 (DMM-1) focuses on better encoding edges regions of depth maps. The large memory required for storing all wedgelet patterns is one of the bottlenecks in the DMM-1 hardware design of both encoder and decoder since many patterns must be stored. Three algorithms to reduce the DMM-1 memory requirements and a hardware design targeting the most efficient among these algorithms are presented. Experimental results demonstrate that the proposed solutions surpass related works reducing up to 78.8% of the wedgelet memory, without degrading the encoding efficiency. Synthesis results demonstrate that the proposed algorithm reduces almost 75% of the power dissipation when compared to the standard approach.
Floyd-warshall algorithm to determine the shortest path based on android

NASA Astrophysics Data System (ADS)

Ramadiani; Bukhori, D.; Azainil; Dengen, N.

2018-04-01

The development of technology has made all areas of life easier now, one of which is the ease of obtaining geographic information. The use of geographic information may vary according to need, for example, the digital map learning, navigation systems, observations area, and much more. With the support of adequate infrastructure, almost no one will ever get lost to a destination even to foreign places or that have never been visited before. The reasons why many institutions and business entities use technology to improve services to consumers and to streamline the production process undertaken and so forth. Speaking of the efficient, there are many elements related to efficiency in navigation systems, and one of them is the efficiency in terms of distance. The shortest distance determination algorithm required in this research is used Floyd-Warshall Algorithm. Floyd-Warshall algorithm is the algorithm to find the fastest path and the shortest distance between 2 nodes, while the program is intended to find the path of more than 2 nodes.
An efficient parallel-processing method for transposing large matrices in place.

PubMed

Portnoff, M R

1999-01-01

We have developed an efficient algorithm for transposing large matrices in place. The algorithm is efficient because data are accessed either sequentially in blocks or randomly within blocks small enough to fit in cache, and because the same indexing calculations are shared among identical procedures operating on independent subsets of the data. This inherent parallelism makes the method well suited for a multiprocessor computing environment. The algorithm is easy to implement because the same two procedures are applied to the data in various groupings to carry out the complete transpose operation. Using only a single processor, we have demonstrated nearly an order of magnitude increase in speed over the previously published algorithm by Gate and Twigg for transposing a large rectangular matrix in place. With multiple processors operating in parallel, the processing speed increases almost linearly with the number of processors. A simplified version of the algorithm for square matrices is presented as well as an extension for matrices large enough to require virtual memory.
Weighted Global Artificial Bee Colony Algorithm Makes Gas Sensor Deployment Efficient

PubMed Central

Jiang, Ye; He, Ziqing; Li, Yanhai; Xu, Zhengyi; Wei, Jianming

2016-01-01

This paper proposes an improved artificial bee colony algorithm named Weighted Global ABC (WGABC) algorithm, which is designed to improve the convergence speed in the search stage of solution search equation. The new method not only considers the effect of global factors on the convergence speed in the search phase, but also provides the expression of global factor weights. Experiment on benchmark functions proved that the algorithm can improve the convergence speed greatly. We arrive at the gas diffusion concentration based on the theory of CFD and then simulate the gas diffusion model with the influence of buildings based on the algorithm. Simulation verified the effectiveness of the WGABC algorithm in improving the convergence speed in optimal deployment scheme of gas sensors. Finally, it is verified that the optimal deployment method based on WGABC algorithm can improve the monitoring efficiency of sensors greatly as compared with the conventional deployment methods. PMID:27322262
Early Obstacle Detection and Avoidance for All to All Traffic Pattern in Wireless Sensor Networks

NASA Astrophysics Data System (ADS)

Huc, Florian; Jarry, Aubin; Leone, Pierre; Moraru, Luminita; Nikoletseas, Sotiris; Rolim, Jose

This paper deals with early obstacles recognition in wireless sensor networks under various traffic patterns. In the presence of obstacles, the efficiency of routing algorithms is increased by voluntarily avoiding some regions in the vicinity of obstacles, areas which we call dead-ends. In this paper, we first propose a fast convergent routing algorithm with proactive dead-end detection together with a formal definition and description of dead-ends. Secondly, we present a generalization of this algorithm which improves performances in all to many and all to all traffic patterns. In a third part we prove that this algorithm produces paths that are optimal up to a constant factor of 2π + 1. In a fourth part we consider the reactive version of the algorithm which is an extension of a previously known early obstacle detection algorithm. Finally we give experimental results to illustrate the efficiency of our algorithms in different scenarios.
The efficiency of average linkage hierarchical clustering algorithm associated multi-scale bootstrap resampling in identifying homogeneous precipitation catchments

NASA Astrophysics Data System (ADS)

Chuan, Zun Liang; Ismail, Noriszura; Shinyie, Wendy Ling; Lit Ken, Tan; Fam, Soo-Fen; Senawi, Azlyna; Yusoff, Wan Nur Syahidah Wan

2018-04-01

Due to the limited of historical precipitation records, agglomerative hierarchical clustering algorithms widely used to extrapolate information from gauged to ungauged precipitation catchments in yielding a more reliable projection of extreme hydro-meteorological events such as extreme precipitation events. However, identifying the optimum number of homogeneous precipitation catchments accurately based on the dendrogram resulted using agglomerative hierarchical algorithms are very subjective. The main objective of this study is to propose an efficient regionalized algorithm to identify the homogeneous precipitation catchments for non-stationary precipitation time series. The homogeneous precipitation catchments are identified using average linkage hierarchical clustering algorithm associated multi-scale bootstrap resampling, while uncentered correlation coefficient as the similarity measure. The regionalized homogeneous precipitation is consolidated using K-sample Anderson Darling non-parametric test. The analysis result shows the proposed regionalized algorithm performed more better compared to the proposed agglomerative hierarchical clustering algorithm in previous studies.
Computationally efficient algorithm for Gaussian Process regression in case of structured samples

NASA Astrophysics Data System (ADS)

Belyaev, M.; Burnaev, E.; Kapushev, Y.

2016-04-01

Surrogate modeling is widely used in many engineering problems. Data sets often have Cartesian product structure (for instance factorial design of experiments with missing points). In such case the size of the data set can be very large. Therefore, one of the most popular algorithms for approximation-Gaussian Process regression-can be hardly applied due to its computational complexity. In this paper a computationally efficient approach for constructing Gaussian Process regression in case of data sets with Cartesian product structure is presented. Efficiency is achieved by using a special structure of the data set and operations with tensors. Proposed algorithm has low computational as well as memory complexity compared to existing algorithms. In this work we also introduce a regularization procedure allowing to take into account anisotropy of the data set and avoid degeneracy of regression model.
Power law-based local search in spider monkey optimisation for lower order system modelling

NASA Astrophysics Data System (ADS)

Sharma, Ajay; Sharma, Harish; Bhargava, Annapurna; Sharma, Nirmala

2017-01-01

The nature-inspired algorithms (NIAs) have shown efficiency to solve many complex real-world optimisation problems. The efficiency of NIAs is measured by their ability to find adequate results within a reasonable amount of time, rather than an ability to guarantee the optimal solution. This paper presents a solution for lower order system modelling using spider monkey optimisation (SMO) algorithm to obtain a better approximation for lower order systems and reflects almost original higher order system's characteristics. Further, a local search strategy, namely, power law-based local search is incorporated with SMO. The proposed strategy is named as power law-based local search in SMO (PLSMO). The efficiency, accuracy and reliability of the proposed algorithm is tested over 20 well-known benchmark functions. Then, the PLSMO algorithm is applied to solve the lower order system modelling problem.
Neural network fusion capabilities for efficient implementation of tracking algorithms

NASA Astrophysics Data System (ADS)

Sundareshan, Malur K.; Amoozegar, Farid

1996-05-01

The ability to efficiently fuse information of different forms for facilitating intelligent decision-making is one of the major capabilities of trained multilayer neural networks that is being recognized int eh recent times. While development of innovative adaptive control algorithms for nonlinear dynamical plants which attempt to exploit these capabilities seems to be more popular, a corresponding development of nonlinear estimation algorithms using these approaches, particularly for application in target surveillance and guidance operations, has not received similar attention. In this paper we describe the capabilities and functionality of neural network algorithms for data fusion and implementation of nonlinear tracking filters. For a discussion of details and for serving as a vehicle for quantitative performance evaluations, the illustrative case of estimating the position and velocity of surveillance targets is considered. Efficient target tracking algorithms that can utilize data from a host of sensing modalities and are capable of reliably tracking even uncooperative targets executing fast and complex maneuvers are of interest in a number of applications. The primary motivation for employing neural networks in these applications comes form the efficiency with which more features extracted from different sensor measurements can be utilized as inputs for estimating target maneuvers. Such an approach results in an overall nonlinear tracking filter which has several advantages over the popular efforts at designing nonlinear estimation algorithms for tracking applications, the principle one being the reduction of mathematical and computational complexities. A system architecture that efficiently integrates the processing capabilities of a trained multilayer neural net with the tracking performance of a Kalman filter is described in this paper.
Improving operating room efficiency by applying bin-packing and portfolio techniques to surgical case scheduling.

PubMed

Van Houdenhoven, Mark; van Oostrum, Jeroen M; Hans, Erwin W; Wullink, Gerhard; Kazemier, Geert

2007-09-01

An operating room (OR) department has adopted an efficient business model and subsequently investigated how efficiency could be further improved. The aim of this study is to show the efficiency improvement of lowering organizational barriers and applying advanced mathematical techniques. We applied advanced mathematical algorithms in combination with scenarios that model relaxation of various organizational barriers using prospectively collected data. The setting is the main inpatient OR department of a university hospital, which sets its surgical case schedules 2 wk in advance using a block planning method. The main outcome measures are the number of freed OR blocks and OR utilization. Lowering organizational barriers and applying mathematical algorithms can yield a 4.5% point increase in OR utilization (95% confidence interval 4.0%-5.0%). This is obtained by reducing the total required OR time. Efficient OR departments can further improve their efficiency. The paper shows that a radical cultural change that comprises the use of mathematical algorithms and lowering organizational barriers improves OR utilization.
Algorithmic Coordination in Robotic Networks

DTIC Science & Technology

2010-11-29

appropriate performance, robustness and scalability properties for various task allocation , surveillance, and information gathering applications is...networking, we envision designing and analyzing algorithms with appropriate performance, robustness and scalability properties for various task ...distributed algorithms for target assignments; based on the classic auction algorithms in static networks, we intend to design efficient algorithms in worst
Efficient Geometric Sound Propagation Using Visibility Culling

NASA Astrophysics Data System (ADS)

Chandak, Anish

2011-07-01

Simulating propagation of sound can improve the sense of realism in interactive applications such as video games and can lead to better designs in engineering applications such as architectural acoustics. In this thesis, we present geometric sound propagation techniques which are faster than prior methods and map well to upcoming parallel multi-core CPUs. We model specular reflections by using the image-source method and model finite-edge diffraction by using the well-known Biot-Tolstoy-Medwin (BTM) model. We accelerate the computation of specular reflections by applying novel visibility algorithms, FastV and AD-Frustum, which compute visibility from a point. We accelerate finite-edge diffraction modeling by applying a novel visibility algorithm which computes visibility from a region. Our visibility algorithms are based on frustum tracing and exploit recent advances in fast ray-hierarchy intersections, data-parallel computations, and scalable, multi-core algorithms. The AD-Frustum algorithm adapts its computation to the scene complexity and allows small errors in computing specular reflection paths for higher computational efficiency. FastV and our visibility algorithm from a region are general, object-space, conservative visibility algorithms that together significantly reduce the number of image sources compared to other techniques while preserving the same accuracy. Our geometric propagation algorithms are an order of magnitude faster than prior approaches for modeling specular reflections and two to ten times faster for modeling finite-edge diffraction. Our algorithms are interactive, scale almost linearly on multi-core CPUs, and can handle large, complex, and dynamic scenes. We also compare the accuracy of our sound propagation algorithms with other methods. Once sound propagation is performed, it is desirable to listen to the propagated sound in interactive and engineering applications. We can generate smooth, artifact-free output audio signals by applying efficient audio-processing algorithms. We also present the first efficient audio-processing algorithm for scenarios with simultaneously moving source and moving receiver (MS-MR) which incurs less than 25% overhead compared to static source and moving receiver (SS-MR) or moving source and static receiver (MS-SR) scenario.
An Orthogonal Evolutionary Algorithm With Learning Automata for Multiobjective Optimization.

PubMed

Dai, Cai; Wang, Yuping; Ye, Miao; Xue, Xingsi; Liu, Hailin

2016-12-01

Research on multiobjective optimization problems becomes one of the hottest topics of intelligent computation. In order to improve the search efficiency of an evolutionary algorithm and maintain the diversity of solutions, in this paper, the learning automata (LA) is first used for quantization orthogonal crossover (QOX), and a new fitness function based on decomposition is proposed to achieve these two purposes. Based on these, an orthogonal evolutionary algorithm with LA for complex multiobjective optimization problems with continuous variables is proposed. The experimental results show that in continuous states, the proposed algorithm is able to achieve accurate Pareto-optimal sets and wide Pareto-optimal fronts efficiently. Moreover, the comparison with the several existing well-known algorithms: nondominated sorting genetic algorithm II, decomposition-based multiobjective evolutionary algorithm, decomposition-based multiobjective evolutionary algorithm with an ensemble of neighborhood sizes, multiobjective optimization by LA, and multiobjective immune algorithm with nondominated neighbor-based selection, on 15 multiobjective benchmark problems, shows that the proposed algorithm is able to find more accurate and evenly distributed Pareto-optimal fronts than the compared ones.
The diffusive finite state projection algorithm for efficient simulation of the stochastic reaction-diffusion master equation.

PubMed

Drawert, Brian; Lawson, Michael J; Petzold, Linda; Khammash, Mustafa

2010-02-21

We have developed a computational framework for accurate and efficient simulation of stochastic spatially inhomogeneous biochemical systems. The new computational method employs a fractional step hybrid strategy. A novel formulation of the finite state projection (FSP) method, called the diffusive FSP method, is introduced for the efficient and accurate simulation of diffusive transport. Reactions are handled by the stochastic simulation algorithm.
Efficient shortest-path-tree computation in network routing based on pulse-coupled neural networks.

PubMed

Qu, Hong; Yi, Zhang; Yang, Simon X

2013-06-01

Shortest path tree (SPT) computation is a critical issue for routers using link-state routing protocols, such as the most commonly used open shortest path first and intermediate system to intermediate system. Each router needs to recompute a new SPT rooted from itself whenever a change happens in the link state. Most commercial routers do this computation by deleting the current SPT and building a new one using static algorithms such as the Dijkstra algorithm at the beginning. Such recomputation of an entire SPT is inefficient, which may consume a considerable amount of CPU time and result in a time delay in the network. Some dynamic updating methods using the information in the updated SPT have been proposed in recent years. However, there are still many limitations in those dynamic algorithms. In this paper, a new modified model of pulse-coupled neural networks (M-PCNNs) is proposed for the SPT computation. It is rigorously proved that the proposed model is capable of solving some optimization problems, such as the SPT. A static algorithm is proposed based on the M-PCNNs to compute the SPT efficiently for large-scale problems. In addition, a dynamic algorithm that makes use of the structure of the previously computed SPT is proposed, which significantly improves the efficiency of the algorithm. Simulation results demonstrate the effective and efficient performance of the proposed approach.
Improving GPU-accelerated adaptive IDW interpolation algorithm using fast kNN search.

PubMed

Mei, Gang; Xu, Nengxiong; Xu, Liangliang

2016-01-01

This paper presents an efficient parallel Adaptive Inverse Distance Weighting (AIDW) interpolation algorithm on modern Graphics Processing Unit (GPU). The presented algorithm is an improvement of our previous GPU-accelerated AIDW algorithm by adopting fast k-nearest neighbors (kNN) search. In AIDW, it needs to find several nearest neighboring data points for each interpolated point to adaptively determine the power parameter; and then the desired prediction value of the interpolated point is obtained by weighted interpolating using the power parameter. In this work, we develop a fast kNN search approach based on the space-partitioning data structure, even grid, to improve the previous GPU-accelerated AIDW algorithm. The improved algorithm is composed of the stages of kNN search and weighted interpolating. To evaluate the performance of the improved algorithm, we perform five groups of experimental tests. The experimental results indicate: (1) the improved algorithm can achieve a speedup of up to 1017 over the corresponding serial algorithm; (2) the improved algorithm is at least two times faster than our previous GPU-accelerated AIDW algorithm; and (3) the utilization of fast kNN search can significantly improve the computational efficiency of the entire GPU-accelerated AIDW algorithm.
Efficient Grammar Induction Algorithm with Parse Forests from Real Corpora

NASA Astrophysics Data System (ADS)

Kurihara, Kenichi; Kameya, Yoshitaka; Sato, Taisuke

The task of inducing grammar structures has received a great deal of attention. The reasons why researchers have studied are different; to use grammar induction as the first stage in building large treebanks or to make up better language models. However, grammar induction has inherent computational complexity. To overcome it, some grammar induction algorithms add new production rules incrementally. They refine the grammar while keeping their computational complexity low. In this paper, we propose a new efficient grammar induction algorithm. Although our algorithm is similar to algorithms which learn a grammar incrementally, our algorithm uses the graphical EM algorithm instead of the Inside-Outside algorithm. We report results of learning experiments in terms of learning speeds. The results show that our algorithm learns a grammar in constant time regardless of the size of the grammar. Since our algorithm decreases syntactic ambiguities in each step, our algorithm reduces required time for learning. This constant-time learning considerably affects learning time for larger grammars. We also reports results of evaluation of criteria to choose nonterminals. Our algorithm refines a grammar based on a nonterminal in each step. Since there can be several criteria to decide which nonterminal is the best, we evaluate them by learning experiments.
An enhanced artificial bee colony algorithm (EABC) for solving dispatching of hydro-thermal system (DHTS) problem.

PubMed

Yu, Yi; Wu, Yonggang; Hu, Binqi; Liu, Xinglong

2018-01-01

The dispatching of hydro-thermal system is a nonlinear programming problem with multiple constraints and high dimensions and the solution techniques of the model have been a hotspot in research. Based on the advantage of that the artificial bee colony algorithm (ABC) can efficiently solve the high-dimensional problem, an improved artificial bee colony algorithm has been proposed to solve DHTS problem in this paper. The improvements of the proposed algorithm include two aspects. On one hand, local search can be guided in efficiency by the information of the global optimal solution and its gradient in each generation. The global optimal solution improves the search efficiency of the algorithm but loses diversity, while the gradient can weaken the loss of diversity caused by the global optimal solution. On the other hand, inspired by genetic algorithm, the nectar resource which has not been updated in limit generation is transformed to a new one by using selection, crossover and mutation, which can ensure individual diversity and make full use of prior information for improving the global search ability of the algorithm. The two improvements of ABC algorithm are proved to be effective via a classical numeral example at last. Among which the genetic operator for the promotion of the ABC algorithm's performance is significant. The results are also compared with those of other state-of-the-art algorithms, the enhanced ABC algorithm has general advantages in minimum cost, average cost and maximum cost which shows its usability and effectiveness. The achievements in this paper provide a new method for solving the DHTS problems, and also offer a novel reference for the improvement of mechanism and the application of algorithms.

An Efficient Supervised Training Algorithm for Multilayer Spiking Neural Networks

PubMed Central

Xie, Xiurui; Qu, Hong; Liu, Guisong; Zhang, Malu; Kurths, Jürgen

2016-01-01

The spiking neural networks (SNNs) are the third generation of neural networks and perform remarkably well in cognitive tasks such as pattern recognition. The spike emitting and information processing mechanisms found in biological cognitive systems motivate the application of the hierarchical structure and temporal encoding mechanism in spiking neural networks, which have exhibited strong computational capability. However, the hierarchical structure and temporal encoding approach require neurons to process information serially in space and time respectively, which reduce the training efficiency significantly. For training the hierarchical SNNs, most existing methods are based on the traditional back-propagation algorithm, inheriting its drawbacks of the gradient diffusion and the sensitivity on parameters. To keep the powerful computation capability of the hierarchical structure and temporal encoding mechanism, but to overcome the low efficiency of the existing algorithms, a new training algorithm, the Normalized Spiking Error Back Propagation (NSEBP) is proposed in this paper. In the feedforward calculation, the output spike times are calculated by solving the quadratic function in the spike response model instead of detecting postsynaptic voltage states at all time points in traditional algorithms. Besides, in the feedback weight modification, the computational error is propagated to previous layers by the presynaptic spike jitter instead of the gradient decent rule, which realizes the layer-wised training. Furthermore, our algorithm investigates the mathematical relation between the weight variation and voltage error change, which makes the normalization in the weight modification applicable. Adopting these strategies, our algorithm outperforms the traditional SNN multi-layer algorithms in terms of learning efficiency and parameter sensitivity, that are also demonstrated by the comprehensive experimental results in this paper. PMID:27044001
Efficient and Stable Routing Algorithm Based on User Mobility and Node Density in Urban Vehicular Network

PubMed Central

Al-Mayouf, Yusor Rafid Bahar; Ismail, Mahamod; Abdullah, Nor Fadzilah; Wahab, Ainuddin Wahid Abdul; Mahdi, Omar Adil; Khan, Suleman; Choo, Kim-Kwang Raymond

2016-01-01

Vehicular ad hoc networks (VANETs) are considered an emerging technology in the industrial and educational fields. This technology is essential in the deployment of the intelligent transportation system, which is targeted to improve safety and efficiency of traffic. The implementation of VANETs can be effectively executed by transmitting data among vehicles with the use of multiple hops. However, the intrinsic characteristics of VANETs, such as its dynamic network topology and intermittent connectivity, limit data delivery. One particular challenge of this network is the possibility that the contributing node may only remain in the network for a limited time. Hence, to prevent data loss from that node, the information must reach the destination node via multi-hop routing techniques. An appropriate, efficient, and stable routing algorithm must be developed for various VANET applications to address the issues of dynamic topology and intermittent connectivity. Therefore, this paper proposes a novel routing algorithm called efficient and stable routing algorithm based on user mobility and node density (ESRA-MD). The proposed algorithm can adapt to significant changes that may occur in the urban vehicular environment. This algorithm works by selecting an optimal route on the basis of hop count and link duration for delivering data from source to destination, thereby satisfying various quality of service considerations. The validity of the proposed algorithm is investigated by its comparison with ARP-QD protocol, which works on the mechanism of optimal route finding in VANETs in urban environments. Simulation results reveal that the proposed ESRA-MD algorithm shows remarkable improvement in terms of delivery ratio, delivery delay, and communication overhead. PMID:27855165
Multi-Complementary Model for Long-Term Tracking

PubMed Central

Zhang, Deng; Zhang, Junchang; Xia, Chenyang

2018-01-01

In recent years, video target tracking algorithms have been widely used. However, many tracking algorithms do not achieve satisfactory performance, especially when dealing with problems such as object occlusions, background clutters, motion blur, low illumination color images, and sudden illumination changes in real scenes. In this paper, we incorporate an object model based on contour information into a Staple tracker that combines the correlation filter model and color model to greatly improve the tracking robustness. Since each model is responsible for tracking specific features, the three complementary models combine for more robust tracking. In addition, we propose an efficient object detection model with contour and color histogram features, which has good detection performance and better detection efficiency compared to the traditional target detection algorithm. Finally, we optimize the traditional scale calculation, which greatly improves the tracking execution speed. We evaluate our tracker on the Object Tracking Benchmarks 2013 (OTB-13) and Object Tracking Benchmarks 2015 (OTB-15) benchmark datasets. With the OTB-13 benchmark datasets, our algorithm is improved by 4.8%, 9.6%, and 10.9% on the success plots of OPE, TRE and SRE, respectively, in contrast to another classic LCT (Long-term Correlation Tracking) algorithm. On the OTB-15 benchmark datasets, when compared with the LCT algorithm, our algorithm achieves 10.4%, 12.5%, and 16.1% improvement on the success plots of OPE, TRE, and SRE, respectively. At the same time, it needs to be emphasized that, due to the high computational efficiency of the color model and the object detection model using efficient data structures, and the speed advantage of the correlation filters, our tracking algorithm could still achieve good tracking speed. PMID:29425170
A Comparative Study of Frequent and Maximal Periodic Pattern Mining Algorithms in Spatiotemporal Databases

NASA Astrophysics Data System (ADS)

Obulesu, O.; Rama Mohan Reddy, A., Dr; Mahendra, M.

2017-08-01

Detecting regular and efficient cyclic models is the demanding activity for data analysts due to unstructured, vigorous and enormous raw information produced from web. Many existing approaches generate large candidate patterns in the occurrence of huge and complex databases. In this work, two novel algorithms are proposed and a comparative examination is performed by considering scalability and performance parameters. The first algorithm is, EFPMA (Extended Regular Model Detection Algorithm) used to find frequent sequential patterns from the spatiotemporal dataset and the second one is, ETMA (Enhanced Tree-based Mining Algorithm) for detecting effective cyclic models with symbolic database representation. EFPMA is an algorithm grows models from both ends (prefixes and suffixes) of detected patterns, which results in faster pattern growth because of less levels of database projection compared to existing approaches such as Prefixspan and SPADE. ETMA uses distinct notions to store and manage transactions data horizontally such as segment, sequence and individual symbols. ETMA exploits a partition-and-conquer method to find maximal patterns by using symbolic notations. Using this algorithm, we can mine cyclic models in full-series sequential patterns including subsection series also. ETMA reduces the memory consumption and makes use of the efficient symbolic operation. Furthermore, ETMA only records time-series instances dynamically, in terms of character, series and section approaches respectively. The extent of the pattern and proving efficiency of the reducing and retrieval techniques from synthetic and actual datasets is a really open & challenging mining problem. These techniques are useful in data streams, traffic risk analysis, medical diagnosis, DNA sequence Mining, Earthquake prediction applications. Extensive investigational outcomes illustrates that the algorithms outperforms well towards efficiency and scalability than ECLAT, STNR and MAFIA approaches.
Function-Based Algorithms for Biological Sequences

ERIC Educational Resources Information Center

Mohanty, Pragyan Sheela P.

2015-01-01

Two problems at two different abstraction levels of computational biology are studied. At the molecular level, efficient pattern matching algorithms in DNA sequences are presented. For gene order data, an efficient data structure is presented capable of storing all gene re-orderings in a systematic manner. A common characteristic of presented…
Fragmenting networks by targeting collective influencers at a mesoscopic level.

PubMed

Kobayashi, Teruyoshi; Masuda, Naoki

2016-11-25

A practical approach to protecting networks against epidemic processes such as spreading of infectious diseases, malware, and harmful viral information is to remove some influential nodes beforehand to fragment the network into small components. Because determining the optimal order to remove nodes is a computationally hard problem, various approximate algorithms have been proposed to efficiently fragment networks by sequential node removal. Morone and Makse proposed an algorithm employing the non-backtracking matrix of given networks, which outperforms various existing algorithms. In fact, many empirical networks have community structure, compromising the assumption of local tree-like structure on which the original algorithm is based. We develop an immunization algorithm by synergistically combining the Morone-Makse algorithm and coarse graining of the network in which we regard a community as a supernode. In this way, we aim to identify nodes that connect different communities at a reasonable computational cost. The proposed algorithm works more efficiently than the Morone-Makse and other algorithms on networks with community structure.
Fragmenting networks by targeting collective influencers at a mesoscopic level

NASA Astrophysics Data System (ADS)

Kobayashi, Teruyoshi; Masuda, Naoki

2016-11-01

A practical approach to protecting networks against epidemic processes such as spreading of infectious diseases, malware, and harmful viral information is to remove some influential nodes beforehand to fragment the network into small components. Because determining the optimal order to remove nodes is a computationally hard problem, various approximate algorithms have been proposed to efficiently fragment networks by sequential node removal. Morone and Makse proposed an algorithm employing the non-backtracking matrix of given networks, which outperforms various existing algorithms. In fact, many empirical networks have community structure, compromising the assumption of local tree-like structure on which the original algorithm is based. We develop an immunization algorithm by synergistically combining the Morone-Makse algorithm and coarse graining of the network in which we regard a community as a supernode. In this way, we aim to identify nodes that connect different communities at a reasonable computational cost. The proposed algorithm works more efficiently than the Morone-Makse and other algorithms on networks with community structure.
Fragmenting networks by targeting collective influencers at a mesoscopic level

PubMed Central

Kobayashi, Teruyoshi; Masuda, Naoki

2016-01-01

A practical approach to protecting networks against epidemic processes such as spreading of infectious diseases, malware, and harmful viral information is to remove some influential nodes beforehand to fragment the network into small components. Because determining the optimal order to remove nodes is a computationally hard problem, various approximate algorithms have been proposed to efficiently fragment networks by sequential node removal. Morone and Makse proposed an algorithm employing the non-backtracking matrix of given networks, which outperforms various existing algorithms. In fact, many empirical networks have community structure, compromising the assumption of local tree-like structure on which the original algorithm is based. We develop an immunization algorithm by synergistically combining the Morone-Makse algorithm and coarse graining of the network in which we regard a community as a supernode. In this way, we aim to identify nodes that connect different communities at a reasonable computational cost. The proposed algorithm works more efficiently than the Morone-Makse and other algorithms on networks with community structure. PMID:27886251
[Preliminary application of an improved Demons deformable registration algorithm in tumor radiotherapy].

PubMed

Zhou, Lu; Zhen, Xin; Lu, Wenting; Dou, Jianhong; Zhou, Linghong

2012-01-01

To validate the efficiency of an improved Demons deformable registration algorithm and evaluate its application in registration of the treatment image and the planning image in image-guided radiotherapy (IGRT). Based on Brox's gradient constancy assumption and Malis's efficient second-order minimization algorithm, a grey value gradient similarity term was added into the original energy function, and a formula was derived to calculate the update of transformation field. The limited Broyden-Fletcher-Goldfarb-Shanno (L-BFGS) algorithm was used to optimize the energy function for automatic determination of the iteration number. The proposed algorithm was validated using mathematically deformed images, physically deformed phantom images and clinical tumor images. Compared with the original Additive Demons algorithm, the improved Demons algorithm achieved a higher precision and a faster convergence speed. Due to the influence of different scanning conditions in fractionated radiation, the density range of the treatment image and the planning image may be different. The improved Demons algorithm can achieve faster and more accurate radiotherapy.
Novel and efficient tag SNPs selection algorithms.

PubMed

Chen, Wen-Pei; Hung, Che-Lun; Tsai, Suh-Jen Jane; Lin, Yaw-Ling

2014-01-01

SNPs are the most abundant forms of genetic variations amongst species; the association studies between complex diseases and SNPs or haplotypes have received great attention. However, these studies are restricted by the cost of genotyping all SNPs; thus, it is necessary to find smaller subsets, or tag SNPs, representing the rest of the SNPs. In fact, the existing tag SNP selection algorithms are notoriously time-consuming. An efficient algorithm for tag SNP selection was presented, which was applied to analyze the HapMap YRI data. The experimental results show that the proposed algorithm can achieve better performance than the existing tag SNP selection algorithms; in most cases, this proposed algorithm is at least ten times faster than the existing methods. In many cases, when the redundant ratio of the block is high, the proposed algorithm can even be thousands times faster than the previously known methods. Tools and web services for haplotype block analysis integrated by hadoop MapReduce framework are also developed using the proposed algorithm as computation kernels.
Explicit symplectic algorithms based on generating functions for charged particle dynamics.

PubMed

Zhang, Ruili; Qin, Hong; Tang, Yifa; Liu, Jian; He, Yang; Xiao, Jianyuan

2016-07-01

Dynamics of a charged particle in the canonical coordinates is a Hamiltonian system, and the well-known symplectic algorithm has been regarded as the de facto method for numerical integration of Hamiltonian systems due to its long-term accuracy and fidelity. For long-term simulations with high efficiency, explicit symplectic algorithms are desirable. However, it is generally believed that explicit symplectic algorithms are only available for sum-separable Hamiltonians, and this restriction limits the application of explicit symplectic algorithms to charged particle dynamics. To overcome this difficulty, we combine the familiar sum-split method and a generating function method to construct second- and third-order explicit symplectic algorithms for dynamics of charged particle. The generating function method is designed to generate explicit symplectic algorithms for product-separable Hamiltonian with form of H(x,p)=p_{i}f(x) or H(x,p)=x_{i}g(p). Applied to the simulations of charged particle dynamics, the explicit symplectic algorithms based on generating functions demonstrate superiorities in conservation and efficiency.
Explicit symplectic algorithms based on generating functions for charged particle dynamics

NASA Astrophysics Data System (ADS)

Zhang, Ruili; Qin, Hong; Tang, Yifa; Liu, Jian; He, Yang; Xiao, Jianyuan

2016-07-01

Dynamics of a charged particle in the canonical coordinates is a Hamiltonian system, and the well-known symplectic algorithm has been regarded as the de facto method for numerical integration of Hamiltonian systems due to its long-term accuracy and fidelity. For long-term simulations with high efficiency, explicit symplectic algorithms are desirable. However, it is generally believed that explicit symplectic algorithms are only available for sum-separable Hamiltonians, and this restriction limits the application of explicit symplectic algorithms to charged particle dynamics. To overcome this difficulty, we combine the familiar sum-split method and a generating function method to construct second- and third-order explicit symplectic algorithms for dynamics of charged particle. The generating function method is designed to generate explicit symplectic algorithms for product-separable Hamiltonian with form of H (x ,p ) =pif (x ) or H (x ,p ) =xig (p ) . Applied to the simulations of charged particle dynamics, the explicit symplectic algorithms based on generating functions demonstrate superiorities in conservation and efficiency.
Research on particle swarm optimization algorithm based on optimal movement probability

NASA Astrophysics Data System (ADS)

Ma, Jianhong; Zhang, Han; He, Baofeng

2017-01-01

The particle swarm optimization algorithm to improve the control precision, and has great application value training neural network and fuzzy system control fields etc.The traditional particle swarm algorithm is used for the training of feed forward neural networks,the search efficiency is low, and easy to fall into local convergence.An improved particle swarm optimization algorithm is proposed based on error back propagation gradient descent. Particle swarm optimization for Solving Least Squares Problems to meme group, the particles in the fitness ranking, optimization problem of the overall consideration, the error back propagation gradient descent training BP neural network, particle to update the velocity and position according to their individual optimal and global optimization, make the particles more to the social optimal learning and less to its optimal learning, it can avoid the particles fall into local optimum, by using gradient information can accelerate the PSO local search ability, improve the multi beam particle swarm depth zero less trajectory information search efficiency, the realization of improved particle swarm optimization algorithm. Simulation results show that the algorithm in the initial stage of rapid convergence to the global optimal solution can be near to the global optimal solution and keep close to the trend, the algorithm has faster convergence speed and search performance in the same running time, it can improve the convergence speed of the algorithm, especially the later search efficiency.
ERGC: an efficient referential genome compression algorithm

PubMed Central

Saha, Subrata; Rajasekaran, Sanguthevar

2015-01-01

Motivation: Genome sequencing has become faster and more affordable. Consequently, the number of available complete genomic sequences is increasing rapidly. As a result, the cost to store, process, analyze and transmit the data is becoming a bottleneck for research and future medical applications. So, the need for devising efficient data compression and data reduction techniques for biological sequencing data is growing by the day. Although there exists a number of standard data compression algorithms, they are not efficient in compressing biological data. These generic algorithms do not exploit some inherent properties of the sequencing data while compressing. To exploit statistical and information-theoretic properties of genomic sequences, we need specialized compression algorithms. Five different next-generation sequencing data compression problems have been identified and studied in the literature. We propose a novel algorithm for one of these problems known as reference-based genome compression. Results: We have done extensive experiments using five real sequencing datasets. The results on real genomes show that our proposed algorithm is indeed competitive and performs better than the best known algorithms for this problem. It achieves compression ratios that are better than those of the currently best performing algorithms. The time to compress and decompress the whole genome is also very promising. Availability and implementation: The implementations are freely available for non-commercial purposes. They can be downloaded from http://engr.uconn.edu/∼rajasek/ERGC.zip. Contact: rajasek@engr.uconn.edu PMID:26139636
Biological network motif detection and evaluation

PubMed Central

2011-01-01

Background Molecular level of biological data can be constructed into system level of data as biological networks. Network motifs are defined as over-represented small connected subgraphs in networks and they have been used for many biological applications. Since network motif discovery involves computationally challenging processes, previous algorithms have focused on computational efficiency. However, we believe that the biological quality of network motifs is also very important. Results We define biological network motifs as biologically significant subgraphs and traditional network motifs are differentiated as structural network motifs in this paper. We develop five algorithms, namely, EDGEGO-BNM, EDGEBETWEENNESS-BNM, NMF-BNM, NMFGO-BNM and VOLTAGE-BNM, for efficient detection of biological network motifs, and introduce several evaluation measures including motifs included in complex, motifs included in functional module and GO term clustering score in this paper. Experimental results show that EDGEGO-BNM and EDGEBETWEENNESS-BNM perform better than existing algorithms and all of our algorithms are applicable to find structural network motifs as well. Conclusion We provide new approaches to finding network motifs in biological networks. Our algorithms efficiently detect biological network motifs and further improve existing algorithms to find high quality structural network motifs, which would be impossible using existing algorithms. The performances of the algorithms are compared based on our new evaluation measures in biological contexts. We believe that our work gives some guidelines of network motifs research for the biological networks. PMID:22784624
Efficient iterative image reconstruction algorithm for dedicated breast CT

NASA Astrophysics Data System (ADS)

Antropova, Natalia; Sanchez, Adrian; Reiser, Ingrid S.; Sidky, Emil Y.; Boone, John; Pan, Xiaochuan

2016-03-01

Dedicated breast computed tomography (bCT) is currently being studied as a potential screening method for breast cancer. The X-ray exposure is set low to achieve an average glandular dose comparable to that of mammography, yielding projection data that contains high levels of noise. Iterative image reconstruction (IIR) algorithms may be well-suited for the system since they potentially reduce the effects of noise in the reconstructed images. However, IIR outcomes can be difficult to control since the algorithm parameters do not directly correspond to the image properties. Also, IIR algorithms are computationally demanding and have optimal parameter settings that depend on the size and shape of the breast and positioning of the patient. In this work, we design an efficient IIR algorithm with meaningful parameter specifications and that can be used on a large, diverse sample of bCT cases. The flexibility and efficiency of this method comes from having the final image produced by a linear combination of two separately reconstructed images - one containing gray level information and the other with enhanced high frequency components. Both of the images result from few iterations of separate IIR algorithms. The proposed algorithm depends on two parameters both of which have a well-defined impact on image quality. The algorithm is applied to numerous bCT cases from a dedicated bCT prototype system developed at University of California, Davis.
Multi-dimensional, fully implicit, exactly conserving electromagnetic particle-in-cell simulations in curvilinear geometry

NASA Astrophysics Data System (ADS)

Chen, Guangye; Chacon, Luis

2015-11-01

We discuss a new, conservative, fully implicit 2D3V Vlasov-Darwin particle-in-cell algorithm in curvilinear geometry for non-radiative, electromagnetic kinetic plasma simulations. Unlike standard explicit PIC schemes, fully implicit PIC algorithms are unconditionally stable and allow exact discrete energy and charge conservation. Here, we extend these algorithms to curvilinear geometry. The algorithm retains its exact conservation properties in curvilinear grids. The nonlinear iteration is effectively accelerated with a fluid preconditioner for weakly to modestly magnetized plasmas, which allows efficient use of large timesteps, O (√{mi/me}c/veT) larger than the explicit CFL. In this presentation, we will introduce the main algorithmic components of the approach, and demonstrate the accuracy and efficiency properties of the algorithm with various numerical experiments in 1D (slow shock) and 2D (island coalescense).
Big Data: A Parallel Particle Swarm Optimization-Back-Propagation Neural Network Algorithm Based on MapReduce

PubMed Central

Cao, Jianfang; Cui, Hongyan; Shi, Hao; Jiao, Lijuan

2016-01-01

A back-propagation (BP) neural network can solve complicated random nonlinear mapping problems; therefore, it can be applied to a wide range of problems. However, as the sample size increases, the time required to train BP neural networks becomes lengthy. Moreover, the classification accuracy decreases as well. To improve the classification accuracy and runtime efficiency of the BP neural network algorithm, we proposed a parallel design and realization method for a particle swarm optimization (PSO)-optimized BP neural network based on MapReduce on the Hadoop platform using both the PSO algorithm and a parallel design. The PSO algorithm was used to optimize the BP neural network’s initial weights and thresholds and improve the accuracy of the classification algorithm. The MapReduce parallel programming model was utilized to achieve parallel processing of the BP algorithm, thereby solving the problems of hardware and communication overhead when the BP neural network addresses big data. Datasets on 5 different scales were constructed using the scene image library from the SUN Database. The classification accuracy of the parallel PSO-BP neural network algorithm is approximately 92%, and the system efficiency is approximately 0.85, which presents obvious advantages when processing big data. The algorithm proposed in this study demonstrated both higher classification accuracy and improved time efficiency, which represents a significant improvement obtained from applying parallel processing to an intelligent algorithm on big data. PMID:27304987
An Algorithm for Timely Transmission of Solicitation Messages in RPL for Energy-Efficient Node Mobility.

PubMed

Park, Jihong; Kim, Ki-Hyung; Kim, Kangseok

2017-04-19

The IPv6 Routing Protocol for Low Power and Lossy Networks (RPL) was proposed for various applications of IPv6 low power wireless networks. While RPL supports various routing metrics and is designed to be suitable for wireless sensor network environments, it does not consider the mobility of nodes. Therefore, there is a need for a method that is energy efficient and that provides stable and reliable data transmission by considering the mobility of nodes in RPL networks. This paper proposes an algorithm to support node mobility in RPL in an energy-efficient manner and describes its operating principle based on different scenarios. The proposed algorithm supports the mobility of nodes by dynamically adjusting the transmission interval of the messages that request the route based on the speed and direction of the motion of mobile nodes, as well as the costs between neighboring nodes. The performance of the proposed algorithm and previous algorithms for supporting node mobility were examined experimentally. From the experiment, it was observed that the proposed algorithm requires fewer messages per unit time for selecting a new parent node following the movement of a mobile node. Since fewer messages are used to select a parent node, the energy consumption is also less than that of previous algorithms.
An Algorithm for Timely Transmission of Solicitation Messages in RPL for Energy-Efficient Node Mobility

PubMed Central

Park, Jihong; Kim, Ki-Hyung; Kim, Kangseok

2017-01-01

The IPv6 Routing Protocol for Low Power and Lossy Networks (RPL) was proposed for various applications of IPv6 low power wireless networks. While RPL supports various routing metrics and is designed to be suitable for wireless sensor network environments, it does not consider the mobility of nodes. Therefore, there is a need for a method that is energy efficient and that provides stable and reliable data transmission by considering the mobility of nodes in RPL networks. This paper proposes an algorithm to support node mobility in RPL in an energy-efficient manner and describes its operating principle based on different scenarios. The proposed algorithm supports the mobility of nodes by dynamically adjusting the transmission interval of the messages that request the route based on the speed and direction of the motion of mobile nodes, as well as the costs between neighboring nodes. The performance of the proposed algorithm and previous algorithms for supporting node mobility were examined experimentally. From the experiment, it was observed that the proposed algorithm requires fewer messages per unit time for selecting a new parent node following the movement of a mobile node. Since fewer messages are used to select a parent node, the energy consumption is also less than that of previous algorithms. PMID:28422084

Versatile and efficient pore network extraction method using marker-based watershed segmentation

NASA Astrophysics Data System (ADS)

Gostick, Jeff T.

2017-08-01

Obtaining structural information from tomographic images of porous materials is a critical component of porous media research. Extracting pore networks is particularly valuable since it enables pore network modeling simulations which can be useful for a host of tasks from predicting transport properties to simulating performance of entire devices. This work reports an efficient algorithm for extracting networks using only standard image analysis techniques. The algorithm was applied to several standard porous materials ranging from sandstone to fibrous mats, and in all cases agreed very well with established or known values for pore and throat sizes, capillary pressure curves, and permeability. In the case of sandstone, the present algorithm was compared to the network obtained using the current state-of-the-art algorithm, and very good agreement was achieved. Most importantly, the network extracted from an image of fibrous media correctly predicted the anisotropic permeability tensor, demonstrating the critical ability to detect key structural features. The highly efficient algorithm allows extraction on fairly large images of 5003 voxels in just over 200 s. The ability for one algorithm to match materials as varied as sandstone with 20% porosity and fibrous media with 75% porosity is a significant advancement. The source code for this algorithm is provided.
Working with Students with Psychiatric Disabilities or Other Emotional Problems

ERIC Educational Resources Information Center

Mazza, Elena T.

2015-01-01

The professional literature on gatekeeping in social work education has grown; however, there remains a dearth in the literature regarding how educators truly work to engage students who are experiencing a psychiatric disability or other emotional problem. This qualitative study explored the experiences of 26 social work educators from 22 colleges…
Rumor Has It: Investigating Teacher Licensure Exam Advice Networks

ERIC Educational Resources Information Center

Baker-Doyle, Kira; Petchauer, Emery

2015-01-01

In many countries, including the United States, England, Korea, Hong Kong, and Japan, individuals must pass some form of examination for entry into or completion of a teacher education program (Wang, Coleman, Coley, & Phelps, 2003). These exams are meant to act as gatekeeping mechanisms for teacher quality. In the majority of the countries…
Improving Student Learning and Views of Physics in a Large Enrollment Introductory Physics Class

ERIC Educational Resources Information Center

Shan, Kathy J.

2013-01-01

Introductory physics courses often serve as gatekeepers for many scientific and engineering programs and, increasingly, colleges are relying on large, lecture formats for these courses. Many students, however, leave having learned very little physics and with poor views of the subject. In interactive engagement (IE), classroom activities encourage…
Beyond Gatekeepers of Knowledge: Scholarly Communication Practices of Academic Librarians and Archivists at ARL Institutions

ERIC Educational Resources Information Center

Sugimoto, Cassidy R.; Tsou, Andrew; Naslund, Sara; Hauser, Alexandra; Brandon, Melissa; Winter, Danielle; Behles, Cody; Finlay, S. Craig

2014-01-01

Librarians and archivists are intimately involved in scholarly communication systems, both as information providers and instructors. However, very little is known regarding their activities as scholars. This study seeks to examine the scholarly communication practices of librarians and archivists, the role that tenure plays in scholarly…
French Immersion for English Language Learners?: Kindergarten Teachers' Perspectives

ERIC Educational Resources Information Center

Mady, Callie

2016-01-01

Given the increasingly diverse, multilingual student body in Canada, the call for increased inclusion in education, and in light of research highlighting the potential for inclusion in French immersion (FI) to be limited by gatekeepers, this study examines the beliefs of kindergarten teachers regarding the inclusion of English language learners in…
Suicide Intervention Training for College Staff: Program Evaluation and Intervention Skill Measurement

ERIC Educational Resources Information Center

Shannonhouse, Laura; Lin, Yung-Wei Dennis; Shaw, Kelly; Wanna, Reema; Porter, Michael

2017-01-01

Objective: Suicide remains a pressing issue for college communities. Consequently, gatekeeper trainings are often provided for staff. This study examines the effect of one such program, Applied Suicide Intervention Skills Training (ASIST). Participants: 51 college employees received ASIST in August of 2014 and were compared to 30 wait-list control…
Threats to Validity in the edTPA Video Component

ERIC Educational Resources Information Center

Choppin, Jeffrey; Meuwissen, Kevin

2017-01-01

The edTPA, a performance assessment designed to generate reliable and valid measures of teaching practice, increasingly is used as a gatekeeping mechanism for beginning teacher licensure in various states, including New York, Washington State, Wisconsin, and Georgia. One of the edTPA's key components is the demonstration of instructional practice…
Helping a District through a Paradigm Shift ... What Have I Gotten Myself into?

ERIC Educational Resources Information Center

Brelsford, Matthew

2010-01-01

Across the country, school psychologists are pushing for a role beyond the traditional refer-test-place model and "gatekeeper" of special education. The broad skill set of school psychologists, including knowledge of curriculum, instruction, data analysis, and intervention, can produce positive results for all students throughout the…
Teaching Nonliterate Adults in Oral Cultures: Findings from Practitioners

ERIC Educational Resources Information Center

Thompson, LaNette W.

2015-01-01

Literacy is the gatekeeper to modern information. In the world today, approximately 740 million adults are excluded from adult education if that education uses literate instructional strategies. Nearly 3/4 of a billion adults, many of whom speak unwritten languages, do not use reading to learn new information nor share information through writing.…
Thoughts on the Law, Gatekeepers, and Rerooting

ERIC Educational Resources Information Center

Shevock, Daniel J.

2017-01-01

This essay extends an open philosophy with a philosophy of music education on soil. An open philosophy emerges from analysis of Kafka's parable "Before the Law." I explore what "the law" might be, what it could mean for how people relate to "the law," and how critiquing "the law" allows music teachers and…
Gatekeepers of a Profession? Employability as Capital in the Recruitment of Medical Interns

ERIC Educational Resources Information Center

Lindberg, Ola

2013-01-01

The present article concerns employability in physicians' professional practice. Drawing on interview data from recruiters at 21 Swedish hospitals with the most applicants for a medical internship, the article seeks to develop a theory of what constitutes an "employable medical intern". Using Pierre Bourdieu's concept of capital, two…
Forum: Learning Outcomes in Communication. The LOCs and the Shift to Student-Centered Learning

ERIC Educational Resources Information Center

Brown, Timothy J.; Castor, Theresa; Byrnes-Loinette, Kerry; Bowman, Jonathan; McBride, Chad

2016-01-01

Traditional teaching is based upon a "teacher"-centered rather than a "student"-centered approach (Bain, 2004). A teacher-centered approach underscores the long held philosophy that instructors are the gatekeepers of knowledge whose job is to convey their knowledge through a lecture, with students as passive receivers during…
Curriculum Gatekeeping in Global Education: Global Educators' Perspectives

ERIC Educational Resources Information Center

Bailey, Robert W.

2013-01-01

Teaching social studies from a global perspective has been resisted by many since its inception (Kirkwood, 2009). Critics have labeled the theory anti-American and unpatriotic (Schlafly, 1986; Burack, 2001). Others are concerned with its shifting perspectives and apparent lack of core facts (Finn, 1988). Over time, some critics have changed their…
High School Teachers' Experiences with Suicidal Students: A Descriptive Study

ERIC Educational Resources Information Center

Freedenthal, Stacey; Breslin, Lindsey

2010-01-01

Teachers are widely considered key gatekeepers to mental health services for students at risk for suicide. Using data from 120 teachers at two Denver-area high schools, this study investigated teachers' experiences with suicidal students. Analyses revealed that the majority of teachers (58.8%) reported that at least one student had disclosed…
Community and Videos: An Action Plan to Increase Success Rates in California Community College Developmental Mathematics

ERIC Educational Resources Information Center

Long, Gary W.

2010-01-01

Success rates in California community college developmental mathematics courses have hovered around 50% for decades. These gatekeeper courses have prevented many students from earning college degrees. Since community college is the starting point for the majority of California's potential college graduates and the majority of these students…
Teacher Educators as Curriculum Developers: Exploration of a Professional Role

ERIC Educational Resources Information Center

Bouckaert, Marina; Kools, Quinta

2018-01-01

Teacher educators arguably fulfil several roles in their professional context: they can be seen as role models or teachers of teachers, and have additionally been characterised as researchers, mentors, gatekeepers, brokers, and curriculum developers. To address a perceived gap in the literature on the latter role, a quantitative and qualitative…
The Role of Legitimacy in Student Teaching: Learning to "Feel" Like a Teacher

ERIC Educational Resources Information Center

Cuenca, Alexander

2011-01-01

A key factor in learning to teach during student teaching is the cooperating teacher, who supports and mentors prospective teachers. In the apprenticeship that is student teaching, the cooperating teacher serves as a gatekeeper to the experiential learning of pre-service teachers. Although several studies indicate the significant influence…
Gateways, Not Gatekeepers

ERIC Educational Resources Information Center

Murray, Linda

2012-01-01

In its analysis of more than 15,000 high school transcripts, the Education Trust-West found that non-college-bound students tend to take a weak academic load and disconnected electives. As a result, far too many students--most often low-income students and students of color--are bound for low-level jobs, prepared for neither college nor career.…
Exploring Some Ethical Dilemmas and Obligations of the Ethnographer

ERIC Educational Resources Information Center

Barbour, Andrew

2010-01-01

This paper focuses on the ethical position of the ethnographer when encountering unethical activities. Ethnography affords a rich insight into cultures, often behind previously secure doors but it is also a demanding science. Our gatekeepers control our access and our relationships with them can determine our destiny. This paper offers an exchange…

Paternal Banking and Maternal Gatekeeping in Postdivorce Families

ERIC Educational Resources Information Center

Moore, Elena

2012-01-01

The research explores the way in which postseparated parents continue to exert a bidirectional force on each other following divorce and separation. The study draws on qualitative interviews with 39 separated mothers and fathers in Ireland, including five marital sets of former couples. The study found many fathers adopted a range of…
Ethnically Diverse Students' Knowledge Structures in First-Semester Organic Chemistry

ERIC Educational Resources Information Center

Lopez, Enrique J.; Shavelson, Richard J.; Nandagopal, Kiruthiga; Szu, Evan; Penn, John

2014-01-01

Chemistry courses remain a challenge for many undergraduate students. In particular, first-semester organic chemistry has been labeled as a gatekeeper with high attrition rates, especially among students of color. Our study examines a key factor related to conceptual understanding in science and predictive of course outcomes-knowledge structures.…
Research Questions: Women and Mass Media.

ERIC Educational Resources Information Center

Busby, Linda J.

Typically, research concerning media presentations of women has involved six types of analysis: (1) content analysis (what is said), (2) cultural and social analysis (why it is said), (3) control or gatekeeper analysis (by whom it is said), (4) audience analysis (to whom it is said), (5) media analysis (in which channel), and (6) effects analysis…
The Impact of Subjective Age and Stigma on Older Persons

ERIC Educational Resources Information Center

Ward, Russell A.

1977-01-01

This study investigated the impact of shifts in age identification by older people (N=323) from "middle-aged" to "elderly" within the context of the labeling theory of deviance. Age identification was unrelated to attitudes toward old people and the label "elderly" did not affect self-esteem through any "gate-keeping" process. (Author)
Race and Racelessness in CMO Marketing: Exploring Charter Management Organizations' Racial Construction and Its Implications

ERIC Educational Resources Information Center

Hernández, Laura E.

2016-01-01

As schools face growing competitive pressures, researchers have investigated the increasing reliance on marketing and its implications for various racial and socioeconomic groups. Although research has expanded our knowledge of marketing's gatekeeping qualities, it has less often considered the manner in which school marketing efforts contribute…
The Developmental Influence of the University Supervisor-Student Teacher Relationship during Clinical Experience

ERIC Educational Resources Information Center

Kucharczuk, Robert Thomas

2017-01-01

The following study examined the perceived developmental influence of the university supervisor-student teacher relationship during the student teaching phase of teacher preparation. Since the supervisor is viewed as the gatekeeper to eventual teacher certification and acts as an evaluator, mentor, and instructor (Borko & Mayfield, 1995;…
Charter School Appeals. Policy Guide

ERIC Educational Resources Information Center

O'Neill, Paul T.

2009-01-01

Authorizers must decide whether a proposed school should be allowed to open and whether it should be required to close. To enable authorizers to serve as quality gatekeepers for the sector, state policy must give authorizers clear power to deny low-quality charter school applications and to close charter schools that fail to meet expectations. At…
Shall We Overcome? Self-Efficacy, Teacher Licensure Exams, and African American Preservice Teachers

ERIC Educational Resources Information Center

Petchauer, Emery

2016-01-01

This article reports findings from a 3-year qualitative study exploring the experiences of African American preservice teachers as they prepared for the Praxis "basic skills" teacher-licensure exam, a gatekeeper to many teacher-education programs. Using the construct of self-efficacy, results illustrate how students assess their Praxis…
Easy as AcHGzrjq: the Quick Letter Name Knowledge Assessment

ERIC Educational Resources Information Center

Tortorelli, Laura S.; Bowles, Ryan P.; Skibbe, Lori E.

2017-01-01

A firm foundation in alphabet knowledge is critical for children learning to read. Under new literacy standards, letter name knowledge in preschool and kindergarten can function as a gatekeeper to the rest of the curriculum. Teachers need data about their students' alphabet knowledge early and often to plan differentiated instruction that moves…
Balancing the Equation: Do Course Variations in Algebra 1 Provide Equal Student Outcomes?

ERIC Educational Resources Information Center

Kenfield, Danielle M.

2013-01-01

Historically, algebra has served as a gatekeeper that divides students into academic programs with varying opportunities to learn and controls access to higher education and career opportunities. Successful completion of Algebra 1 demonstrates mathematical proficiency and allows access to a sequential and progressive path of advanced study that…
Deciding Access to Work-Integrated Learning: Human Resource Professionals as Gatekeepers

ERIC Educational Resources Information Center

Mackaway, Jacqueline; Winchester-Seeto, Theresa

2018-01-01

Universities, industry and professional bodies advocate work-integrated learning (WIL) as a valuable way to prepare graduates to meet the challenges of contemporary society. When organizations preference particular students over others to host on placement, the full individual and collective potential of WIL is not realized. This paper reports…
A Qualitative Study of One District's Efforts to Improve Mathematics Instruction to Scale

ERIC Educational Resources Information Center

Osborne, Brian George

2011-01-01

Mathematics learning is critical for student success, and frequently acts as a gatekeeper, preventing students from graduating from high school and pursuing higher education. While many districts have attempted to improve mathematics instruction by implementing some sort of reform, few districts have attempted to execute a multifaceted systems…
An Australian Indigenous community-led suicide intervention skills training program: community consultation findings.

PubMed

Nasir, Bushra; Kisely, Steve; Hides, Leanne; Ranmuthugala, Geetha; Brennan-Olsen, Sharon; Nicholson, Geoffrey C; Gill, Neeraj S; Hayman, Noel; Kondalsamy-Chennakesavan, Srinivas; Toombs, Maree

2017-06-13

Little is known of the appropriateness of existing gatekeeper suicide prevention programs for Indigenous communities. Despite the high rates of Indigenous suicide in Australia, especially among Indigenous youth, it is unclear how effective existing suicide prevention programs are in providing appropriate management of Indigenous people at risk of suicide. In-depth, semi-structured interviews and focus groups were conducted with Indigenous communities in rural and regional areas of Southern Queensland. Thematic analysis was performed on the gathered information. Existing programs were time-intensive and included content irrelevant to Indigenous people. There was inconsistency in the content and delivery of gatekeeper training. Programs were also not sustainable for rural and regional Indigenous communities. Appropriate programs should be practical, relevant, and sustainable across all Indigenous communities, with a focus on the social, emotional, cultural and spiritual underpinnings of community wellbeing. Programs need to be developed in thorough consultation with Indigenous communities. Indigenous-led suicide intervention training programs are needed to mitigate the increasing rates of suicide experienced by Indigenous peoples living in rural and remote locations.
Characteristics of African American women caregivers of children with asthma.

PubMed

Sterling, Yvonne M; Peterson, Jane W

2003-01-01

To describe the attributes and characteristics of African American women who were the primary caregivers of children with asthma. Descriptive qualitative ethnography. Data collection consisted of formal interviews, participant observation, and fieldnotes. Each study participant was formally and informally interviewed (audiotaped) during a 1-year period. The researchers also observed and participated in family activities in various naturalistic settings. Six themes emerged that depict the characteristics of these women: (1) Knowledge about the child's asthma; (2) Gatekeepers to the child's care; (3) Being religious; (4) Support; (5) Roles as teacher, counselor, and advisor to the child; and (6) Self-sufficiency and industriousness. Nurses should use the information in this study to examine the ways in which they interact with caregivers of asthmatic children. The caregivers personal beliefs, need for information, and previous experiences with asthma and family illness should be assessed. These mothers and grandmothers should be respected as the gatekeeper to the family's healthcare. Nurses should be nonjudgmental and supportive of caregivers when they express their religious beliefs and practices. Nurses who understand how mothers cope can reinforce these coping skills and provide better nursing care.
Self-perceived Coparenting of Nonresident Fathers: Scale Development and Validation.

PubMed

Dyer, W Justin; Fagan, Jay; Kaufman, Rebecca; Pearson, Jessica; Cabrera, Natasha

2017-11-16

This study reports on the development and validation of the Fatherhood Research and Practice Network coparenting perceptions scale for nonresident fathers. Although other measures of coparenting have been developed, this is the first measure developed specifically for low-income, nonresident fathers. Focus groups were conducted to determine various aspects of coparenting. Based on this, a scale was created and administered to 542 nonresident fathers. Participants also responded to items used to examine convergent and predictive validity (i.e., parental responsibility, contact with the mother, father self-efficacy and satisfaction, child behavior problems, and contact and engagement with the child). Factor analyses and reliability tests revealed three distinct and reliable perceived coparenting factors: undermining, alliance, and gatekeeping. Validity tests suggest substantial overlap between the undermining and alliance factors, though undermining was uniquely related to child behavior problems. The alliance and gatekeeping factors showed strong convergent validity and evidence for predictive validity. Taken together, results suggest this relatively short measure (11 items) taps into three coparenting dimensions significantly predictive of aspects of individual and family life. © 2017 Family Process Institute.
Cultural stereotypes as gatekeepers: increasing girls' interest in computer science and engineering by diversifying stereotypes.

PubMed

Cheryan, Sapna; Master, Allison; Meltzoff, Andrew N

2015-01-01

Despite having made significant inroads into many traditionally male-dominated fields (e.g., biology, chemistry), women continue to be underrepresented in computer science and engineering. We propose that students' stereotypes about the culture of these fields-including the kind of people, the work involved, and the values of the field-steer girls away from choosing to enter them. Computer science and engineering are stereotyped in modern American culture as male-oriented fields that involve social isolation, an intense focus on machinery, and inborn brilliance. These stereotypes are compatible with qualities that are typically more valued in men than women in American culture. As a result, when computer science and engineering stereotypes are salient, girls report less interest in these fields than their male peers. However, altering these stereotypes-by broadening the representation of the people who do this work, the work itself, and the environments in which it occurs-significantly increases girls' sense of belonging and interest in the field. Academic stereotypes thus serve as gatekeepers, driving girls away from certain fields and constraining their learning opportunities and career aspirations.
Cultural stereotypes as gatekeepers: increasing girls’ interest in computer science and engineering by diversifying stereotypes

PubMed Central

Cheryan, Sapna; Master, Allison; Meltzoff, Andrew N.

2015-01-01

Despite having made significant inroads into many traditionally male-dominated fields (e.g., biology, chemistry), women continue to be underrepresented in computer science and engineering. We propose that students’ stereotypes about the culture of these fields—including the kind of people, the work involved, and the values of the field—steer girls away from choosing to enter them. Computer science and engineering are stereotyped in modern American culture as male-oriented fields that involve social isolation, an intense focus on machinery, and inborn brilliance. These stereotypes are compatible with qualities that are typically more valued in men than women in American culture. As a result, when computer science and engineering stereotypes are salient, girls report less interest in these fields than their male peers. However, altering these stereotypes—by broadening the representation of the people who do this work, the work itself, and the environments in which it occurs—significantly increases girls’ sense of belonging and interest in the field. Academic stereotypes thus serve as gatekeepers, driving girls away from certain fields and constraining their learning opportunities and career aspirations. PMID:25717308
A descriptive study of baccalaureate nursing students' responses to suicide prevention education.

PubMed

Pullen, Julie M; Gilje, Fredricka; Tesar, Emily

2016-01-01

Internationally, little is known regarding the amount of educational content on suicide in undergraduate nursing curriculum. The literature conducted found few published research studies on implementation of suicide prevention instruction in baccalaureate nursing curriculum, even though various international healthcare and nursing initiatives address suicide prevention. The aim was to describe senior baccalaureate students' responses to an evidence-based suicide prevention gatekeeper training program entitled Question-Persuade-Refer implemented in a required course. This is a multi-method descriptive study. Data were collected utilizing a pre-post-survey questionnaire administered to 150 students in four classes of a psychiatric nursing course over a two-year period. The quantitative data were statistically significant (p < 0.000) indicating an overall positive rating of the training. From the qualitative data, the main theme was 'becoming capable intervening with persons at risk for suicide'. Students responded very positively to the evidence based suicide prevention gatekeeper training program. The instruction addresses various national initiatives and strategies filling a void in nursing curriculum, as well as empowering students to engage in suicide prevention interventions. Copyright © 2015 Elsevier Ltd. All rights reserved.
Physicians as gatekeepers: illness certification as a rationing device.

PubMed

Stone, D A

1979-01-01

Illness or disability is often used as an eligibility criterion by public programs that distribute money, services, privileges, and exemptions. Physicians then play a central role in the allocation process. But physicians are caught between a large pool of applicants who want some benefit, on the one hand, and an organization with limited resources to distribute, on the other hand. Three conflicts are engendered in this gatekeeping role: the tension between trusting and mistrusting information provided by the patient, the tension between erring on the false positive side and the false negative side in diagnostic decision-making, and the tension between doing everything possible for each patient and allocating limited resources among several needy clients. Several non-medical factors influence the ultimate outcome of this allocation process, which, in theory, rests on clinical decision-making: the specificity and restrictiveness of the formal definitions of illness and disability used by a program; the structure of the determination process; the overall policy of the organization on distribution of benefits; and the ability of the organization to use administrative review, direct incentives, and written standards to control the certifying behavior of physicians.
Network gatekeeping: complementary medicine information on the websites of medical institutions.

PubMed

Keshet, Yael

2012-03-01

Integrative medicine - complementary and alternative medicine (CAM) practised in mainstream healthcare organizations - combines medical treatments based on incommensurable paradigms. As the Internet has been portrayed as a crucial pathway to CAM and sites administered by reputable organizations are considered to be relatively reliable sources of medical information, the research sought to explore and compare the ways in which CAM is presented on the Internet websites of diverse medical institutions. The contents of the websites of the Ministry of Health, the Israeli Medical Association and Israeli healthcare organizations were analysed, using an interdisciplinary theory of network gatekeeping. The websites were analysed not only according to the degree to which they are considered to be informative, but also with regard to the perceptions of integration that they convey. Comparison of the websites of community healthcare organizations and hospitals indicates that while the former display CAM treatments as an attractive commodity, the latter convey a message stressing the need to subject CAM to bio-medical scrutiny. Little or no information was provided concerning a number of important issues, such as research findings about efficacy and safety, risks and ethical considerations.

Time-Dependent CO[subscript 2] Sorption Hysteresis in a One-Dimensional Microporous Octahedral Molecular Sieve

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

Espinal, Laura; Wong-Ng, Winnie; Kaduk, James A.

2014-09-24

The development of sorbents for next-generation CO{sub 2} mitigation technologies will require better understanding of CO{sub 2}/sorbent interactions. Among the sorbents under consideration are shape-selective microporous molecular sieves with hierarchical pore morphologies of reduced dimensionality. We have characterized the non-equilibrium CO{sub 2} sorption of OMS-2, a well-known one-dimensional microporous octahedral molecular sieve with manganese oxide framework. Remarkably, we find that the degree of CO{sub 2} sorption hysteresis increases when the gas/sorbent system is allowed to equilibrate for longer times at each pressure step. Density functional theory calculations indicate a 'gate-keeping' role of the cation in the tunnel, only allowing CO{submore » 2} molecules to enter fully into the tunnel via a highly unstable transient state when CO{sub 2} loadings exceed 0.75 mmol/g. The energy barrier associated with the gate-keeping effect suggests an adsorption mechanism in which kinetic trapping of CO{sub 2} is responsible for the observed hysteretic behavior.« less
Mental Health Services for Children and Youth in the Child Welfare System: A Focus on Caregivers as Gatekeepers.

PubMed

Villagrana, Margarita

2010-05-01

Caregivers serve as gatekeepers for children while in the child welfare system, but few studies have focused on the caregiver and the factors that influence the use of mental health services for the children under their care. The purpose of this study was to examine the child's mental health need, the caregiver's level of stress, depression, and social support, and the utilization of mental health services by children using the three most common types of caregivers in the child welfare system (i.e., birth parent, relative caregiver, and foster parent). Data comes from the Patterns of Care (POC) study of five public sectors of care. The present study examined parents/caregivers and youth from the child welfare sector. Findings suggest that while birth parents were more likely to endorse more risk factors for themselves, and the children under their care had a higher level of mental health need, they were the least likely to utilize mental health services for the children under their care. Implications for the child welfare and mental health systems are discussed.
A novel hybrid algorithm for the design of the phase diffractive optical elements for beam shaping

NASA Astrophysics Data System (ADS)

Jiang, Wenbo; Wang, Jun; Dong, Xiucheng

2013-02-01

In this paper, a novel hybrid algorithm for the design of a phase diffractive optical elements (PDOE) is proposed. It combines the genetic algorithm (GA) with the transformable scale BFGS (Broyden, Fletcher, Goldfarb, Shanno) algorithm, the penalty function was used in the cost function definition. The novel hybrid algorithm has the global merits of the genetic algorithm as well as the local improvement capabilities of the transformable scale BFGS algorithm. We designed the PDOE using the conventional simulated annealing algorithm and the novel hybrid algorithm. To compare the performance of two algorithms, three indexes of the diffractive efficiency, uniformity error and the signal-to-noise ratio are considered in numerical simulation. The results show that the novel hybrid algorithm has good convergence property and good stability. As an application example, the PDOE was used for the Gaussian beam shaping; high diffractive efficiency, low uniformity error and high signal-to-noise were obtained. The PDOE can be used for high quality beam shaping such as inertial confinement fusion (ICF), excimer laser lithography, fiber coupling laser diode array, laser welding, etc. It shows wide application value.
Efficient characterisation of large deviations using population dynamics

NASA Astrophysics Data System (ADS)

Brewer, Tobias; Clark, Stephen R.; Bradford, Russell; Jack, Robert L.

2018-05-01

We consider population dynamics as implemented by the cloning algorithm for analysis of large deviations of time-averaged quantities. We use the simple symmetric exclusion process with periodic boundary conditions as a prototypical example and investigate the convergence of the results with respect to the algorithmic parameters, focussing on the dynamical phase transition between homogeneous and inhomogeneous states, where convergence is relatively difficult to achieve. We discuss how the performance of the algorithm can be optimised, and how it can be efficiently exploited on parallel computing platforms.
Efficient Classical Algorithm for Boson Sampling with Partially Distinguishable Photons

NASA Astrophysics Data System (ADS)

Renema, J. J.; Menssen, A.; Clements, W. R.; Triginer, G.; Kolthammer, W. S.; Walmsley, I. A.

2018-06-01

We demonstrate how boson sampling with photons of partial distinguishability can be expressed in terms of interference of fewer photons. We use this observation to propose a classical algorithm to simulate the output of a boson sampler fed with photons of partial distinguishability. We find conditions for which this algorithm is efficient, which gives a lower limit on the required indistinguishability to demonstrate a quantum advantage. Under these conditions, adding more photons only polynomially increases the computational cost to simulate a boson sampling experiment.
Traffic off-balancing algorithm for energy efficient networks

NASA Astrophysics Data System (ADS)

Kim, Junhyuk; Lee, Chankyun; Rhee, June-Koo Kevin

2011-12-01

Physical layer of high-end network system uses multiple interface arrays. Under the load-balancing perspective, light load can be distributed to multiple interfaces. However, it can cause energy inefficiency in terms of the number of poor utilization interfaces. To tackle this energy inefficiency, traffic off-balancing algorithm for traffic adaptive interface sleep/awake is investigated. As a reference model, 40G/100G Ethernet is investigated. We report that suggested algorithm can achieve energy efficiency while satisfying traffic transmission requirement.
A high-performance spatial database based approach for pathology imaging algorithm evaluation

PubMed Central

Wang, Fusheng; Kong, Jun; Gao, Jingjing; Cooper, Lee A.D.; Kurc, Tahsin; Zhou, Zhengwen; Adler, David; Vergara-Niedermayr, Cristobal; Katigbak, Bryan; Brat, Daniel J.; Saltz, Joel H.

2013-01-01

Background: Algorithm evaluation provides a means to characterize variability across image analysis algorithms, validate algorithms by comparison with human annotations, combine results from multiple algorithms for performance improvement, and facilitate algorithm sensitivity studies. The sizes of images and image analysis results in pathology image analysis pose significant challenges in algorithm evaluation. We present an efficient parallel spatial database approach to model, normalize, manage, and query large volumes of analytical image result data. This provides an efficient platform for algorithm evaluation. Our experiments with a set of brain tumor images demonstrate the application, scalability, and effectiveness of the platform. Context: The paper describes an approach and platform for evaluation of pathology image analysis algorithms. The platform facilitates algorithm evaluation through a high-performance database built on the Pathology Analytic Imaging Standards (PAIS) data model. Aims: (1) Develop a framework to support algorithm evaluation by modeling and managing analytical results and human annotations from pathology images; (2) Create a robust data normalization tool for converting, validating, and fixing spatial data from algorithm or human annotations; (3) Develop a set of queries to support data sampling and result comparisons; (4) Achieve high performance computation capacity via a parallel data management infrastructure, parallel data loading and spatial indexing optimizations in this infrastructure. Materials and Methods: We have considered two scenarios for algorithm evaluation: (1) algorithm comparison where multiple result sets from different methods are compared and consolidated; and (2) algorithm validation where algorithm results are compared with human annotations. We have developed a spatial normalization toolkit to validate and normalize spatial boundaries produced by image analysis algorithms or human annotations. The validated data were formatted based on the PAIS data model and loaded into a spatial database. To support efficient data loading, we have implemented a parallel data loading tool that takes advantage of multi-core CPUs to accelerate data injection. The spatial database manages both geometric shapes and image features or classifications, and enables spatial sampling, result comparison, and result aggregation through expressive structured query language (SQL) queries with spatial extensions. To provide scalable and efficient query support, we have employed a shared nothing parallel database architecture, which distributes data homogenously across multiple database partitions to take advantage of parallel computation power and implements spatial indexing to achieve high I/O throughput. Results: Our work proposes a high performance, parallel spatial database platform for algorithm validation and comparison. This platform was evaluated by storing, managing, and comparing analysis results from a set of brain tumor whole slide images. The tools we develop are open source and available to download. Conclusions: Pathology image algorithm validation and comparison are essential to iterative algorithm development and refinement. One critical component is the support for queries involving spatial predicates and comparisons. In our work, we develop an efficient data model and parallel database approach to model, normalize, manage and query large volumes of analytical image result data. Our experiments demonstrate that the data partitioning strategy and the grid-based indexing result in good data distribution across database nodes and reduce I/O overhead in spatial join queries through parallel retrieval of relevant data and quick subsetting of datasets. The set of tools in the framework provide a full pipeline to normalize, load, manage and query analytical results for algorithm evaluation. PMID:23599905
An artificial bee colony algorithm for locating the critical slip surface in slope stability analysis

NASA Astrophysics Data System (ADS)

Kang, Fei; Li, Junjie; Ma, Zhenyue

2013-02-01

Determination of the critical slip surface with the minimum factor of safety of a slope is a difficult constrained global optimization problem. In this article, an artificial bee colony algorithm with a multi-slice adjustment method is proposed for locating the critical slip surfaces of soil slopes, and the Spencer method is employed to calculate the factor of safety. Six benchmark examples are presented to illustrate the reliability and efficiency of the proposed technique, and it is also compared with some well-known or recent algorithms for the problem. The results show that the new algorithm is promising in terms of accuracy and efficiency.
Interaction sorting method for molecular dynamics on multi-core SIMD CPU architecture.

PubMed

Matvienko, Sergey; Alemasov, Nikolay; Fomin, Eduard

2015-02-01

Molecular dynamics (MD) is widely used in computational biology for studying binding mechanisms of molecules, molecular transport, conformational transitions, protein folding, etc. The method is computationally expensive; thus, the demand for the development of novel, much more efficient algorithms is still high. Therefore, the new algorithm designed in 2007 and called interaction sorting (IS) clearly attracted interest, as it outperformed the most efficient MD algorithms. In this work, a new IS modification is proposed which allows the algorithm to utilize SIMD processor instructions. This paper shows that the improvement provides an additional gain in performance, 9% to 45% in comparison to the original IS method.
Algorithm for calculating turbine cooling flow and the resulting decrease in turbine efficiency

NASA Technical Reports Server (NTRS)

Gauntner, J. W.

1980-01-01

An algorithm is presented for calculating both the quantity of compressor bleed flow required to cool the turbine and the decrease in turbine efficiency caused by the injection of cooling air into the gas stream. The algorithm, which is intended for an axial flow, air routine in a properly written thermodynamic cycle code. Ten different cooling configurations are available for each row of cooled airfoils in the turbine. Results from the algorithm are substantiated by comparison with flows predicted by major engine manufacturers for given bulk metal temperatures and given cooling configurations. A list of definitions for the terms in the subroutine is presented.
On the efficient and reliable numerical solution of rate-and-state friction problems

NASA Astrophysics Data System (ADS)

Pipping, Elias; Kornhuber, Ralf; Rosenau, Matthias; Oncken, Onno

2016-03-01

We present a mathematically consistent numerical algorithm for the simulation of earthquake rupture with rate-and-state friction. Its main features are adaptive time stepping, a novel algebraic solution algorithm involving nonlinear multigrid and a fixed point iteration for the rate-and-state decoupling. The algorithm is applied to a laboratory scale subduction zone which allows us to compare our simulations with experimental results. Using physical parameters from the experiment, we find a good fit of recurrence time of slip events as well as their rupture width and peak slip. Computations in 3-D confirm efficiency and robustness of our algorithm.
Signal Partitioning Algorithm for Highly Efficient Gaussian Mixture Modeling in Mass Spectrometry

PubMed Central

Polanski, Andrzej; Marczyk, Michal; Pietrowska, Monika; Widlak, Piotr; Polanska, Joanna

2015-01-01

Mixture - modeling of mass spectra is an approach with many potential applications including peak detection and quantification, smoothing, de-noising, feature extraction and spectral signal compression. However, existing algorithms do not allow for automated analyses of whole spectra. Therefore, despite highlighting potential advantages of mixture modeling of mass spectra of peptide/protein mixtures and some preliminary results presented in several papers, the mixture modeling approach was so far not developed to the stage enabling systematic comparisons with existing software packages for proteomic mass spectra analyses. In this paper we present an efficient algorithm for Gaussian mixture modeling of proteomic mass spectra of different types (e.g., MALDI-ToF profiling, MALDI-IMS). The main idea is automated partitioning of protein mass spectral signal into fragments. The obtained fragments are separately decomposed into Gaussian mixture models. The parameters of the mixture models of fragments are then aggregated to form the mixture model of the whole spectrum. We compare the elaborated algorithm to existing algorithms for peak detection and we demonstrate improvements of peak detection efficiency obtained by using Gaussian mixture modeling. We also show applications of the elaborated algorithm to real proteomic datasets of low and high resolution. PMID:26230717
PRESEE: An MDL/MML Algorithm to Time-Series Stream Segmenting

PubMed Central

Jiang, Yexi; Tang, Mingjie; Yuan, Changan; Tang, Changjie

2013-01-01

Time-series stream is one of the most common data types in data mining field. It is prevalent in fields such as stock market, ecology, and medical care. Segmentation is a key step to accelerate the processing speed of time-series stream mining. Previous algorithms for segmenting mainly focused on the issue of ameliorating precision instead of paying much attention to the efficiency. Moreover, the performance of these algorithms depends heavily on parameters, which are hard for the users to set. In this paper, we propose PRESEE (parameter-free, real-time, and scalable time-series stream segmenting algorithm), which greatly improves the efficiency of time-series stream segmenting. PRESEE is based on both MDL (minimum description length) and MML (minimum message length) methods, which could segment the data automatically. To evaluate the performance of PRESEE, we conduct several experiments on time-series streams of different types and compare it with the state-of-art algorithm. The empirical results show that PRESEE is very efficient for real-time stream datasets by improving segmenting speed nearly ten times. The novelty of this algorithm is further demonstrated by the application of PRESEE in segmenting real-time stream datasets from ChinaFLUX sensor networks data stream. PMID:23956693
PRESEE: an MDL/MML algorithm to time-series stream segmenting.

PubMed

Xu, Kaikuo; Jiang, Yexi; Tang, Mingjie; Yuan, Changan; Tang, Changjie

2013-01-01

Time-series stream is one of the most common data types in data mining field. It is prevalent in fields such as stock market, ecology, and medical care. Segmentation is a key step to accelerate the processing speed of time-series stream mining. Previous algorithms for segmenting mainly focused on the issue of ameliorating precision instead of paying much attention to the efficiency. Moreover, the performance of these algorithms depends heavily on parameters, which are hard for the users to set. In this paper, we propose PRESEE (parameter-free, real-time, and scalable time-series stream segmenting algorithm), which greatly improves the efficiency of time-series stream segmenting. PRESEE is based on both MDL (minimum description length) and MML (minimum message length) methods, which could segment the data automatically. To evaluate the performance of PRESEE, we conduct several experiments on time-series streams of different types and compare it with the state-of-art algorithm. The empirical results show that PRESEE is very efficient for real-time stream datasets by improving segmenting speed nearly ten times. The novelty of this algorithm is further demonstrated by the application of PRESEE in segmenting real-time stream datasets from ChinaFLUX sensor networks data stream.
Local flow management/profile descent algorithm. Fuel-efficient, time-controlled profiles for the NASA TSRV airplane

NASA Technical Reports Server (NTRS)

Groce, J. L.; Izumi, K. H.; Markham, C. H.; Schwab, R. W.; Thompson, J. L.

1986-01-01

The Local Flow Management/Profile Descent (LFM/PD) algorithm designed for the NASA Transport System Research Vehicle program is described. The algorithm provides fuel-efficient altitude and airspeed profiles consistent with ATC restrictions in a time-based metering environment over a fixed ground track. The model design constraints include accommodation of both published profile descent procedures and unpublished profile descents, incorporation of fuel efficiency as a flight profile criterion, operation within the performance capabilities of the Boeing 737-100 airplane with JT8D-7 engines, and conformity to standard air traffic navigation and control procedures. Holding and path stretching capabilities are included for long delay situations.
An enhanced artificial bee colony algorithm (EABC) for solving dispatching of hydro-thermal system (DHTS) problem

PubMed Central

Yu, Yi; Hu, Binqi; Liu, Xinglong

2018-01-01

The dispatching of hydro-thermal system is a nonlinear programming problem with multiple constraints and high dimensions and the solution techniques of the model have been a hotspot in research. Based on the advantage of that the artificial bee colony algorithm (ABC) can efficiently solve the high-dimensional problem, an improved artificial bee colony algorithm has been proposed to solve DHTS problem in this paper. The improvements of the proposed algorithm include two aspects. On one hand, local search can be guided in efficiency by the information of the global optimal solution and its gradient in each generation. The global optimal solution improves the search efficiency of the algorithm but loses diversity, while the gradient can weaken the loss of diversity caused by the global optimal solution. On the other hand, inspired by genetic algorithm, the nectar resource which has not been updated in limit generation is transformed to a new one by using selection, crossover and mutation, which can ensure individual diversity and make full use of prior information for improving the global search ability of the algorithm. The two improvements of ABC algorithm are proved to be effective via a classical numeral example at last. Among which the genetic operator for the promotion of the ABC algorithm’s performance is significant. The results are also compared with those of other state-of-the-art algorithms, the enhanced ABC algorithm has general advantages in minimum cost, average cost and maximum cost which shows its usability and effectiveness. The achievements in this paper provide a new method for solving the DHTS problems, and also offer a novel reference for the improvement of mechanism and the application of algorithms. PMID:29324743
Parallel Directionally Split Solver Based on Reformulation of Pipelined Thomas Algorithm

NASA Technical Reports Server (NTRS)

Povitsky, A.

1998-01-01

In this research an efficient parallel algorithm for 3-D directionally split problems is developed. The proposed algorithm is based on a reformulated version of the pipelined Thomas algorithm that starts the backward step computations immediately after the completion of the forward step computations for the first portion of lines This algorithm has data available for other computational tasks while processors are idle from the Thomas algorithm. The proposed 3-D directionally split solver is based on the static scheduling of processors where local and non-local, data-dependent and data-independent computations are scheduled while processors are idle. A theoretical model of parallelization efficiency is used to define optimal parameters of the algorithm, to show an asymptotic parallelization penalty and to obtain an optimal cover of a global domain with subdomains. It is shown by computational experiments and by the theoretical model that the proposed algorithm reduces the parallelization penalty about two times over the basic algorithm for the range of the number of processors (subdomains) considered and the number of grid nodes per subdomain.
The application of dynamic programming in production planning

NASA Astrophysics Data System (ADS)

Wu, Run

2017-05-01

Nowadays, with the popularity of the computers, various industries and fields are widely applying computer information technology, which brings about huge demand for a variety of application software. In order to develop software meeting various needs with most economical cost and best quality, programmers must design efficient algorithms. A superior algorithm can not only soul up one thing, but also maximize the benefits and generate the smallest overhead. As one of the common algorithms, dynamic programming algorithms are used to solving problems with some sort of optimal properties. When solving problems with a large amount of sub-problems that needs repetitive calculations, the ordinary sub-recursive method requires to consume exponential time, and dynamic programming algorithm can reduce the time complexity of the algorithm to the polynomial level, according to which we can conclude that dynamic programming algorithm is a very efficient compared to other algorithms reducing the computational complexity and enriching the computational results. In this paper, we expound the concept, basic elements, properties, core, solving steps and difficulties of the dynamic programming algorithm besides, establish the dynamic programming model of the production planning problem.
Optimal cost design of water distribution networks using a decomposition approach

NASA Astrophysics Data System (ADS)

Lee, Ho Min; Yoo, Do Guen; Sadollah, Ali; Kim, Joong Hoon

2016-12-01

Water distribution network decomposition, which is an engineering approach, is adopted to increase the efficiency of obtaining the optimal cost design of a water distribution network using an optimization algorithm. This study applied the source tracing tool in EPANET, which is a hydraulic and water quality analysis model, to the decomposition of a network to improve the efficiency of the optimal design process. The proposed approach was tested by carrying out the optimal cost design of two water distribution networks, and the results were compared with other optimal cost designs derived from previously proposed optimization algorithms. The proposed decomposition approach using the source tracing technique enables the efficient decomposition of an actual large-scale network, and the results can be combined with the optimal cost design process using an optimization algorithm. This proves that the final design in this study is better than those obtained with other previously proposed optimization algorithms.
Image restoration for three-dimensional fluorescence microscopy using an orthonormal basis for efficient representation of depth-variant point-spread functions

PubMed Central

Patwary, Nurmohammed; Preza, Chrysanthe

2015-01-01

A depth-variant (DV) image restoration algorithm for wide field fluorescence microscopy, using an orthonormal basis decomposition of DV point-spread functions (PSFs), is investigated in this study. The efficient PSF representation is based on a previously developed principal component analysis (PCA), which is computationally intensive. We present an approach developed to reduce the number of DV PSFs required for the PCA computation, thereby making the PCA-based approach computationally tractable for thick samples. Restoration results from both synthetic and experimental images show consistency and that the proposed algorithm addresses efficiently depth-induced aberration using a small number of principal components. Comparison of the PCA-based algorithm with a previously-developed strata-based DV restoration algorithm demonstrates that the proposed method improves performance by 50% in terms of accuracy and simultaneously reduces the processing time by 64% using comparable computational resources. PMID:26504634

Some links on this page may take you to non-federal websites. Their policies may differ from this site.