Infants Learn Baby Signs From Video

PubMed Central

Dayanim, Shoshana; Namy, Laura L.

2014-01-01

There is little evidence that infants learn from infant-oriented educational videos and television programming. This four week longitudinal experiment investigated 15-month-olds’ (N=92) ability to learn ASL signs (e.g., patting head for hat) from at-home viewing of instructional video, either with or without parent support, compared to traditional parent instruction and a no-exposure control condition. Forced choice, elicited production, and parent report measures indicate learning across all three exposure conditions, with a trend towards more robust learning in the parent support conditions, regardless of medium. There were no differences between experimental and control conditions in the acquisition of corresponding verbal labels. This constitutes the first experimental evidence of infants’ ability to learn expressive communication from commercially available educational videos. PMID:25622926

Teacher Opinions on Performance Pay: Evidence from India

ERIC Educational Resources Information Center

Muralidharan, Karthik; Sundararaman, Venkatesh

2011-01-01

The practical viability of performance-based pay programs for teachers depends critically on the extent of support the idea will receive from teachers. We present evidence on teacher opinions with regard to performance-based pay from teacher interviews conducted in the context of an experimental evaluation of a program that provided…

Inbreeding depression by environment interactions in a free-living mammal population

PubMed Central

Pemberton, J M; Ellis, P E; Pilkington, J G; Bérénos, C

2017-01-01

Experimental studies often find that inbreeding depression is more severe in harsh environments, but the few studies of in situ wild populations available to date rarely find strong support for this effect. We investigated evidence for inbreeding depression by environment interactions in nine traits in the individually monitored Soay sheep population of St Kilda, using genomic inbreeding coefficients based on 37 037 single-nucleotide polymorphism loci, and population density as an axis of environmental variation. All traits showed variation with population density and all traits showed some evidence for depression because of either an individual's own inbreeding or maternal inbreeding. However, only six traits showed evidence for an interaction in the expected direction, and only two interactions were statistically significant. We identify three possible reasons why wild population studies may generally fail to find strong support for interactions between inbreeding depression and environmental variation compared with experimental studies. First, for species with biparental inbreeding only, the amount of observed inbreeding in natural populations is generally low compared with that used in experimental studies. Second, it is possible that experimental studies sometimes actually impose higher levels of stress than organisms experience in the wild. Third, some purging of the deleterious recessive alleles that underpin interaction effects may occur in the wild. PMID:27876804

Inbreeding depression by environment interactions in a free-living mammal population.

PubMed

Pemberton, J M; Ellis, P E; Pilkington, J G; Bérénos, C

2017-01-01

Experimental studies often find that inbreeding depression is more severe in harsh environments, but the few studies of in situ wild populations available to date rarely find strong support for this effect. We investigated evidence for inbreeding depression by environment interactions in nine traits in the individually monitored Soay sheep population of St Kilda, using genomic inbreeding coefficients based on 37 037 single-nucleotide polymorphism loci, and population density as an axis of environmental variation. All traits showed variation with population density and all traits showed some evidence for depression because of either an individual's own inbreeding or maternal inbreeding. However, only six traits showed evidence for an interaction in the expected direction, and only two interactions were statistically significant. We identify three possible reasons why wild population studies may generally fail to find strong support for interactions between inbreeding depression and environmental variation compared with experimental studies. First, for species with biparental inbreeding only, the amount of observed inbreeding in natural populations is generally low compared with that used in experimental studies. Second, it is possible that experimental studies sometimes actually impose higher levels of stress than organisms experience in the wild. Third, some purging of the deleterious recessive alleles that underpin interaction effects may occur in the wild.

The impact of feedback valence and communication style on intrinsic motivation in middle childhood: Experimental evidence and generalization across individual differences.

PubMed

Mabbe, Elien; Soenens, Bart; De Muynck, Gert-Jan; Vansteenkiste, Maarten

2018-06-01

Prior research among adolescents and emerging adults has provided evidence for the beneficial effects of positive (relative to negative) feedback and an autonomy-supportive (relative to a controlling) communication style on students' intrinsic motivation. Unfortunately, similar experimental research in middle childhood is lacking. Moreover, little attention has been paid to the question of whether individual differences in personality and perceived parenting play a role in these effects. In the current experimental study (N = 110; M age  = 10.71 years), children completed puzzles at school under one of four experimental conditions, thereby crossing normative feedback valence (i.e., positive vs. negative) with communication style (i.e., autonomy supportive vs. controlling). Prior to the experiment, children filled out questionnaires tapping into the Big Five personality traits and into perceived maternal autonomy support and psychological control. After the experimental induction, children rated several motivational constructs (i.e., intrinsic motivation and need-based experiences). In addition, their voluntary behavioral persistence in a subsequent challenging puzzle task was recorded objectively. Providing positive normative feedback in an autonomy-supportive way yielded the most favorable motivational outcomes. Both feedback valence and communication style yielded an independent impact on children's experiences of competence and autonomy during task engagement, which in turn helped to explain children's elevated intrinsic motivation, as reflected by their perceived interest and behavioral persistence. A few effects were moderated by children's perceived parenting and personality traits, but the number of interactions was limited. The discussion focuses on the motivating role of positive normative feedback and an autonomy-supportive communication style for children. Copyright © 2018 Elsevier Inc. All rights reserved.

Does Linguistic Analysis Confirm the Validity of Facilitated Communication?

ERIC Educational Resources Information Center

Saloviita, Timo

2018-01-01

Facilitated communication (FC) has been interpreted as an ideomotor phenomenon, in which one person physically supports another person's hand and unconsciously affects the content of the writing. Despite the strong experimental evidence against the authenticity of FC output, several studies claim to support its validity based on idiosyncrasies…

Suppressing hillock formation in Si-supported pure Al films

NASA Astrophysics Data System (ADS)

Liu, N. Z.; Liu, Y.

2018-04-01

To suppress the hillock formation and hence improve the service performance of pure Al thin films deposited on Si substrate, dependence of hillock formation on film thickness and annealing temperature was systematically investigated. Experimental results revealed that the hillock volume increased linearly with both the film thickness and annealing temperature. While the evolution of hillock density with film thickness was complicated, strongly depending on the annealing temperature. It was evident that the hillock formation could be effectively suppressed at a critical annealing temperature especially in thinner thickness, similar to the previous findings in Mo/glass-supported pure Al films. These experimental evidences clearly demonstrated that the hillock formation should be controlled by the plastic deformation in the surrounding film, which was further rationalized by a micromechanics model.

Are anorexia nervosa and bulimia nervosa separate disorders? Challenging the 'transdiagnostic' theory of eating disorders.

PubMed

Birmingham, C Laird; Touyz, Stephen; Harbottle, Jane

2009-01-01

Anorexia nervosa (AN) and bulimia nervosa (BN) are classified as separate and distinct clinical disorders. Recently, there has been support for a transdiagnostic theory of eating disorders, which would reclassify them as one disorder. To determine whether AN and BN are a single disorder with one cause or separate disorders with different causes. Hill's Criteria of Causation were used to test the hypothesis that AN and BN are one disorder with a single cause. Hill's Criteria of Causation demand that the minimal conditions are needed to establish a causal relationship between two items which include all of the following: strength of association, consistency, temporality, biological gradient, plausibility, coherence, experimental evidence and analogy. The hypothesis that AN and BN have a single cause did not meet all of Hill's Criteria of Causation. Strength of association, plausibility, analogy and some experimental evidence were met, but not consistency, specificity, temporality, biological gradient, coherence and most experimental evidence. The hypothesis that AN and BN are a single disorder with a common cause is not supported by Hill's Criteria of Causation. This argues against the notion of a transdiagnostic theory of eating disorders.

Experimental identification of nitrogen-vacancy complexes in nitrogen implanted silicon

NASA Astrophysics Data System (ADS)

Adam, Lahir Shaik; Law, Mark E.; Szpala, Stanislaw; Simpson, P. J.; Lawther, Derek; Dokumaci, Omer; Hegde, Suri

2001-07-01

Nitrogen implantation is commonly used in multigate oxide thickness processing for mixed signal complementary metal-oxide-semiconductor and System on a Chip technologies. Current experiments and diffusion models indicate that upon annealing, implanted nitrogen diffuses towards the surface. The mechanism proposed for nitrogen diffusion is the formation of nitrogen-vacancy complexes in silicon, as indicated by ab initio studies by J. S. Nelson, P. A. Schultz, and A. F. Wright [Appl. Phys. Lett. 73, 247 (1998)]. However, to date, there does not exist any experimental evidence of nitrogen-vacancy formation in silicon. This letter provides experimental evidence through positron annihilation spectroscopy that nitrogen-vacancy complexes indeed form in nitrogen implanted silicon, and compares the experimental results to the ab initio studies, providing qualitative support for the same.

Evaluation of Long Composite Struts

NASA Technical Reports Server (NTRS)

Jegley, Dawn C.; Wu, K. Chauncey; Phelps, James E.; McKenney, Martin J.; Oremont, Leonard; Barnard, Ansley

2011-01-01

Carbon-epoxy tapered struts are structurally efficient and offer opportunities for weight savings on aircraft and spacecraft structures. Seven composite struts were designed, fabricated and experimentally evaluated through uniaxial loading. The design requirements, analytical predictions and experimental results are presented. Struts with a tapered composite body and corrugated titanium end fittings successfully supported their design ultimate loads with no evidence of failure.

Facilitating healthcare decisions by assessing the certainty in the evidence from preclinical animal studies

PubMed Central

Hooijmans, Carlijn R.; de Vries, Rob B. M.; Ritskes-Hoitinga, Merel; Rovers, Maroeska M.; Leeflang, Mariska M.; IntHout, Joanna; Wever, Kimberley E.; Hooft, Lotty; de Beer, Hans; Kuijpers, Ton; Macleod, Malcolm R.; Sena, Emily S.; ter Riet, Gerben; Morgan, Rebecca L.; Thayer, Kristina A.; Rooney, Andrew A.; Guyatt, Gordon H.; Schünemann, Holger J.

2018-01-01

Laboratory animal studies are used in a wide range of human health related research areas, such as basic biomedical research, drug research, experimental surgery and environmental health. The results of these studies can be used to inform decisions regarding clinical research in humans, for example the decision to proceed to clinical trials. If the research question relates to potential harms with no expectation of benefit (e.g., toxicology), studies in experimental animals may provide the only relevant or controlled data and directly inform clinical management decisions. Systematic reviews and meta-analyses are important tools to provide robust and informative evidence summaries of these animal studies. Rating how certain we are about the evidence could provide important information about the translational probability of findings in experimental animal studies to clinical practice and probably improve it. Evidence summaries and certainty in the evidence ratings could also be used (1) to support selection of interventions with best therapeutic potential to be tested in clinical trials, (2) to justify a regulatory decision limiting human exposure (to drug or toxin), or to (3) support decisions on the utility of further animal experiments. The Grading of Recommendations, Assessment, Development, and Evaluation (GRADE) approach is the most widely used framework to rate the certainty in the evidence and strength of health care recommendations. Here we present how the GRADE approach could be used to rate the certainty in the evidence of preclinical animal studies in the context of therapeutic interventions. We also discuss the methodological challenges that we identified, and for which further work is needed. Examples are defining the importance of consistency within and across animal species and using GRADE’s indirectness domain as a tool to predict translation from animal models to humans. PMID:29324741

Facilitating healthcare decisions by assessing the certainty in the evidence from preclinical animal studies.

PubMed

Hooijmans, Carlijn R; de Vries, Rob B M; Ritskes-Hoitinga, Merel; Rovers, Maroeska M; Leeflang, Mariska M; IntHout, Joanna; Wever, Kimberley E; Hooft, Lotty; de Beer, Hans; Kuijpers, Ton; Macleod, Malcolm R; Sena, Emily S; Ter Riet, Gerben; Morgan, Rebecca L; Thayer, Kristina A; Rooney, Andrew A; Guyatt, Gordon H; Schünemann, Holger J; Langendam, Miranda W

2018-01-01

Laboratory animal studies are used in a wide range of human health related research areas, such as basic biomedical research, drug research, experimental surgery and environmental health. The results of these studies can be used to inform decisions regarding clinical research in humans, for example the decision to proceed to clinical trials. If the research question relates to potential harms with no expectation of benefit (e.g., toxicology), studies in experimental animals may provide the only relevant or controlled data and directly inform clinical management decisions. Systematic reviews and meta-analyses are important tools to provide robust and informative evidence summaries of these animal studies. Rating how certain we are about the evidence could provide important information about the translational probability of findings in experimental animal studies to clinical practice and probably improve it. Evidence summaries and certainty in the evidence ratings could also be used (1) to support selection of interventions with best therapeutic potential to be tested in clinical trials, (2) to justify a regulatory decision limiting human exposure (to drug or toxin), or to (3) support decisions on the utility of further animal experiments. The Grading of Recommendations, Assessment, Development, and Evaluation (GRADE) approach is the most widely used framework to rate the certainty in the evidence and strength of health care recommendations. Here we present how the GRADE approach could be used to rate the certainty in the evidence of preclinical animal studies in the context of therapeutic interventions. We also discuss the methodological challenges that we identified, and for which further work is needed. Examples are defining the importance of consistency within and across animal species and using GRADE's indirectness domain as a tool to predict translation from animal models to humans.

Does the First Week of Class Matter? A Quasi-Experimental Investigation of Student Satisfaction

ERIC Educational Resources Information Center

Hermann, Anthony D.; Foster, David A.; Hardin, Erin E.

2010-01-01

Teaching experts suggest that establishing clear expectations and a supportive environment at the beginning of a college course has a lasting impact on student attitudes. However, minimal empirical evidence exists to support these suggestions. Consequently, we randomly assigned instructors to either begin their course with a reciprocal interview…

Local isotropy and refractive index fluctuations in the surface layer of the atmosphere

NASA Technical Reports Server (NTRS)

Portman, D. J.

1969-01-01

Theoretical and experimental evidence for the existence of local isotropy is briefly examined and conflicting results are found. Recent measurements of temperature spectra support earlier hot wire anemometer and optical scintillation measurements that show little evidence of local isotropy at 1 to 1.5 meters over an extensive uniform and level grass covered field.

Origin of microbial life: Nano- and molecular events, thermodynamics/entropy, quantum mechanisms and genetic instructions.

PubMed

Trevors, J T

2011-03-01

Currently, there are no agreed upon mechanisms and supporting evidence for the origin of the first microbial cells on the Earth. However, some hypotheses have been proposed with minimal supporting evidence and experimentation/observations. The approach taken in this article is that life originated at the nano- and molecular levels of biological organization, using quantum mechanic principles that became manifested as classical microbial cell(s), allowing the origin of microbial life on the Earth with a core or minimal, organic, genetic code containing the correct instructions for cell(s) for growth and division, in a micron dimension environment, with a local entropy range conducive to life (present about 4 billion years ago), and obeying the laws of thermodynamics. An integrated approach that explores all encompassing factors necessary for the origin of life, may bring forth plausible hypotheses (and mechanisms) with much needed supporting experimentation and observations for an origin of life theory. Copyright © 2010 Elsevier B.V. All rights reserved.

Analysis of the pressure-induced potential arising through composite membranes with selective surface layers.

PubMed

Szymczyk, Anthony; Sbaï, Mohammed; Fievet, Patrick

2005-03-01

When a pressure gradient is applied through a charged selective membrane, the transmembrane electrical potential difference, called the filtration potential, results from both the applied pressure and induced concentration difference across the membrane. In this work we investigate the electrokinetic properties relative to both active and support layers of a composite ceramic membrane close to the nanofiltration range. First, the volume charge density of the active layer is obtained by fitting a transport model to experimental rejection rates (which are controlled by the active layer only). Next, the value of the volume charge density is used to compute the theoretical filtration potential through the active layer. For sufficiently high permeate volume fluxes, the concentration difference across the active layer becomes constant, which allows assessing the membrane potential of the active layer. Experimental measurements of the overall filtration potential arising through the whole membrane are performed. The contribution of the support layer to this overall filtration potential is put in evidence. That implies that the membrane potential of the active layer cannot be deduced directly from the overall filtration potential measurements. Finally, the contribution of the support layer is singled out by subtracting the theoretical filtration potential of the active layer from the experimental filtration potential measured across the whole membrane (i.e., support + active layers). The amphoteric behavior of both layers is put in evidence, which is confirmed by electrophoretic measurements carried out with the powdered support layer and by recently reported tangential streaming potential measurements.

On the Psychology of Truth-Gaps

NASA Astrophysics Data System (ADS)

Alxatib, Sam; Pelletier, Jeff

Bonini et al. [2] present psychological data that they take to support an 'epistemic' account of how vague predicates are used in natural language. We argue that their data more strongly supports a 'gap' theory of vagueness, and that their arguments against gap theories are flawed. Additionally, we present more experimental evidence that supports gap theories, and argue for a semantic/pragmatic alternative that unifies super- and subvaluationary approaches to vagueness.

A search for the evidence supporting community paediatric practice

PubMed Central

Rudolf, M; Lyth, N; Bundle, A; Rowland, G; Kelly, A; Bosson, S; Garner, M; Guest, P; Khan, M; Thazin, R; Bennett, T; Damman, D; Cove, V; Kaur, V

1999-01-01

AIM—Controversy exists regarding the evidence base of medicine. Estimates range from 20% to 80% in various specialties, but there have been no studies in paediatrics. The aim of this study was to ascertain the evidence base for community paediatrics.
METHODS—Twelve community paediatricians working in clinics and schools in Yorkshire, Manchester, Teesside, and Cheshire carried out a prospective review of consecutive clinical contacts. Evidence for diagnostic processes, prescribing, referrals, counselling/advice, and child health promotion was found by searching electronic databases. This information was critically appraised and a consensus was obtained regarding quality and whether it supported actions taken.
RESULTS—Two hundred and forty seven consultations and 1149 clinical actions were performed. Good evidence was found from a randomised controlled trial or other appropriate study for 39.9% of the 629actions studied; convincing non-experimental evidence for 7%; inconclusive evidence for 25.4%; evidence of ineffectiveness for 0.2%; and no evidence for 27.5%. Prescribing and child health promotion activities had the highest levels of quality evidence, and counselling/advice had the lowest.
CONCLUSIONS—An encouraging amount of evidence was found to support much of community paediatric practice. This study improved on previous research in other specialties because actions other than medications and surgery were included.

 PMID:10325707

An Experimental, Hands-on Approach to Epithelial Ion Transport: A Simple Technique for Introducing Students to Ion Transport in Epithelia

ERIC Educational Resources Information Center

Bagdadi, Andrea; Orona, Nadia; Fernandez, Eugenio; Altamirano, Anibal; Amorena, Carlos

2010-01-01

We have realized that our Biology undergraduate students learn biological concepts as established truths without awareness of the body of experimental evidence supporting the emerging models as usually presented in handbooks and texts in general. Therefore, we have implemented a laboratory practice in our course of Physiology and Biophysics, aimed…

The Learning of Grammar: An Experimental Study. Experimental Studies on the Learning of Language, Progress Report II, Revised.

ERIC Educational Resources Information Center

Torrey, Jane W.

An experiment in language behavior comparing two methods of learning grammatical word order in a new language presents scientific evidence supporting the use of pattern drills in foreign language teaching. The experiment reviews the performance of three groups attempting to learn small segments of Russian "microlanguage": (1) a drill group learned…

Average Treatment Effect of School-Wide Positive Behavioral Interventions and Supports on School-Level Academic Achievement in Florida

ERIC Educational Resources Information Center

Gage, Nicholas A.; Leite, Walter; Childs, Karen; Kincaid, Don

2017-01-01

The relationship between school-wide positive behavioral interventions and supports (SWPBIS) and school-level academic achievement has not been established. Most experimental research has found little to no evidence that SWPBIS has a distal effect on school-level achievement. Yet, an underlying assumption of SWPBIS is that improving social…

Evidence of negative-index refraction in nonlinear chemical waves.

PubMed

Yuan, Xujin; Wang, Hongli; Ouyang, Qi

2011-05-06

The negative index of refraction of nonlinear chemical waves has become a recent focus in nonlinear dynamics researches. Theoretical analysis and computer simulations have predicted that the negative index of refraction can occur on the interface between antiwaves and normal waves in a reaction-diffusion (RD) system. However, no experimental evidence has been found so far. In this Letter, we report our experimental design in searching for such a phenomenon in a chlorite-iodide-malonic acid (CIMA) reaction. Our experimental results demonstrate that competition between waves and antiwaves at their interface determines the fate of the wave interaction. The negative index of refraction was only observed when the oscillation frequency of a normal wave is significantly smaller than that of the antiwave. All experimental results were supported by simulations using the Lengyel-Epstein RD model which describes the CIMA reaction-diffusion system.

Prospective Links between Friendship and Early Physical Aggression: Preliminary Evidence Supporting the Role of Friendship Quality through a Dyadic Intervention

ERIC Educational Resources Information Center

Salvas, Marie-Claude; Vitaro, Frank; Brendgen, Mara; Cantin, Ste´phane

2016-01-01

Positive friendships have been related to decreasing levels of children's physical aggression over time. While this evidence calls for interventions aimed at helping children build good-quality friendships, tests of causality through experimental manipulations are still needed. The goal of this study was to examine whether an intervention aimed to…

Short- and long-term memory contributions to immediate serial recognition: evidence from serial position effects.

PubMed

Purser, Harry; Jarrold, Christopher

2010-04-01

A long-standing body of research supports the existence of separable short- and long-term memory systems, relying on phonological and semantic codes, respectively. The aim of the current study was to measure the contribution of long-term knowledge to short-term memory performance by looking for evidence of phonologically and semantically coded storage within a short-term recognition task, among developmental samples. Each experimental trial presented 4-item lists. In Experiment 1 typically developing children aged 5 to 6 years old showed evidence of phonologically coded storage across all 4 serial positions, but evidence of semantically coded storage at Serial Positions 1 and 2. In a further experiment, a group of individuals with Down syndrome was investigated as a test case that might be expected to use semantic coding to support short-term storage, but these participants showed no evidence of semantically coded storage and evidenced phonologically coded storage only at Serial Position 4, suggesting that individuals with Down syndrome have a verbal short-term memory capacity of 1 item. Our results suggest that previous evidence of semantic effects on "short-term memory performance" does not reflect semantic coding in short-term memory itself, and provide an experimental method for researchers wishing to take a relatively pure measure of verbal short-term memory capacity, in cases where rehearsal is unlikely.

Current hypotheses for the evolution of sex and recombination.

PubMed

Hartfield, Matthew; Keightley, Peter D

2012-06-01

The evolution of sex is one of the most important and controversial problems in evolutionary biology. Although sex is almost universal in higher animals and plants, its inherent costs have made its maintenance difficult to explain. The most famous of these is the twofold cost of males, which can greatly reduce the fecundity of a sexual population, compared to a population of asexual females. Over the past century, multiple hypotheses, along with experimental evidence to support these, have been put forward to explain widespread costly sex. In this review, we outline some of the most prominent theories, along with the experimental and observational evidence supporting these. Historically, there have been 4 classes of theories: the ability of sex to fix multiple novel advantageous mutants (Fisher-Muller hypothesis); sex as a mechanism to stop the build-up of deleterious mutations in finite populations (Muller's ratchet); recombination creating novel genotypes that can resist infection by parasites (Red Queen hypothesis); and the ability of sex to purge bad genomes if deleterious mutations act synergistically (mutational deterministic hypothesis). Current theoretical and experimental evidence seems to favor the hypothesis that sex breaks down selection interference between new mutants, or it acts as a mechanism to shuffle genotypes in order to repel parasitic invasion. However, there is still a need to collect more data from natural populations and experimental studies, which can be used to test different hypotheses. © 2012 ISZS, Blackwell Publishing and IOZ/CAS.

The effects of prosocial video games on prosocial behaviors: international evidence from correlational, longitudinal, and experimental studies.

PubMed

Gentile, Douglas A; Anderson, Craig A; Yukawa, Shintaro; Ihori, Nobuko; Saleem, Muniba; Ming, Lim Kam; Shibuya, Akiko; Liau, Albert K; Khoo, Angeline; Bushman, Brad J; Rowell Huesmann, L; Sakamoto, Akira

2009-06-01

Although dozens of studies have documented a relationship between violent video games and aggressive behaviors, very little attention has been paid to potential effects of prosocial games. Theoretically, games in which game characters help and support each other in nonviolent ways should increase both short-term and long-term prosocial behaviors. We report three studies conducted in three countries with three age groups to test this hypothesis. In the correlational study, Singaporean middle-school students who played more prosocial games behaved more prosocially. In the two longitudinal samples of Japanese children and adolescents, prosocial game play predicted later increases in prosocial behavior. In the experimental study, U.S. undergraduates randomly assigned to play prosocial games behaved more prosocially toward another student. These similar results across different methodologies, ages, and cultures provide robust evidence of a prosocial game content effect, and they provide support for the General Learning Model.

The scientific consensus on climate change as a gateway belief: experimental evidence.

PubMed

van der Linden, Sander L; Leiserowitz, Anthony A; Feinberg, Geoffrey D; Maibach, Edward W

2015-01-01

There is currently widespread public misunderstanding about the degree of scientific consensus on human-caused climate change, both in the US as well as internationally. Moreover, previous research has identified important associations between public perceptions of the scientific consensus, belief in climate change and support for climate policy. This paper extends this line of research by advancing and providing experimental evidence for a "gateway belief model" (GBM). Using national data (N = 1104) from a consensus-message experiment, we find that increasing public perceptions of the scientific consensus is significantly and causally associated with an increase in the belief that climate change is happening, human-caused and a worrisome threat. In turn, changes in these key beliefs are predictive of increased support for public action. In short, we find that perceived scientific agreement is an important gateway belief, ultimately influencing public responses to climate change.

The Effects of Prosocial Video Games on Prosocial Behaviors: International Evidence from Correlational, Longitudinal, and Experimental Studies

PubMed Central

Gentile, Douglas A.; Anderson, Craig A.; Yukawa, Shintaro; Ihori, Nobuko; Saleem, Muniba; Ming, Lim Kam; Shibuya, Akiko; Liau, Albert K.; Khoo, Angeline; Bushman, Brad J.; Huesmann, L. Rowell; Sakamoto, Akira

2009-01-01

Although dozens of studies have documented a relation between violent video games and aggressive behaviors, very little attention has been paid to potential effects of prosocial games. Theoretically, games in which game characters help and support each other in nonviolent ways should increase both short-term and long-term prosocial behaviors. We report three studies conducted in three countries with three age groups to test this hypothesis. In the correlational study, Singaporean middle-school students who played more prosocial games behaved more prosocially. In the two longitudinal samples of Japanese children and adolescents, prosocial game play predicted later increases in prosocial behavior. In the experimental study, U.S. undergraduates randomly assigned to play prosocial games behaved more prosocially toward another student. These similar results across different methodologies, ages, and cultures provide robust evidence a prosocial game content effect, and provide support for the General Learning Model. PMID:19321812

The Scientific Consensus on Climate Change as a Gateway Belief: Experimental Evidence

PubMed Central

van der Linden, Sander L.; Leiserowitz, Anthony A.; Feinberg, Geoffrey D.; Maibach, Edward W.

2015-01-01

There is currently widespread public misunderstanding about the degree of scientific consensus on human-caused climate change, both in the US as well as internationally. Moreover, previous research has identified important associations between public perceptions of the scientific consensus, belief in climate change and support for climate policy. This paper extends this line of research by advancing and providing experimental evidence for a “gateway belief model” (GBM). Using national data (N = 1104) from a consensus-message experiment, we find that increasing public perceptions of the scientific consensus is significantly and causally associated with an increase in the belief that climate change is happening, human-caused and a worrisome threat. In turn, changes in these key beliefs are predictive of increased support for public action. In short, we find that perceived scientific agreement is an important gateway belief, ultimately influencing public responses to climate change. PMID:25714347

The Effects of Evidence Bounds on Decision-Making: Theoretical and Empirical Developments

PubMed Central

Zhang, Jiaxiang

2012-01-01

Converging findings from behavioral, neurophysiological, and neuroimaging studies suggest an integration-to-boundary mechanism governing decision formation and choice selection. This mechanism is supported by sequential sampling models of choice decisions, which can implement statistically optimal decision strategies for selecting between multiple alternative options on the basis of sensory evidence. This review focuses on recent developments in understanding the evidence boundary, an important component of decision-making raised by experimental findings and models. The article starts by reviewing the neurobiology of perceptual decisions and several influential sequential sampling models, in particular the drift-diffusion model, the Ornstein–Uhlenbeck model and the leaky-competing-accumulator model. In the second part, the article examines how the boundary may affect a model’s dynamics and performance and to what extent it may improve a model’s fits to experimental data. In the third part, the article examines recent findings that support the presence and site of boundaries in the brain. The article considers two questions: (1) whether the boundary is a spontaneous property of neural integrators, or is controlled by dedicated neural circuits; (2) if the boundary is variable, what could be the driving factors behind boundary changes? The review brings together studies using different experimental methods in seeking answers to these questions, highlights psychological and physiological factors that may be associated with the boundary and its changes, and further considers the evidence boundary as a generic mechanism to guide complex behavior. PMID:22870070

The Effectiveness of Support Groups in Asian Breast Cancer Patients: An Integrative Review.

PubMed

Chou, Fang-Yu; Lee-Lin, Frances; Kuang, Lily Y

2016-01-01

Cancer support group has been studied as an intervention to improve patient psychosocial well-being. The effectiveness of support groups among Asian breast cancer (BC) patients has been unclear and received limited attention to the evidence of its effectiveness. The social-cognitive processing theory underlies the principles of support groups and advocates that a positive, supportive social environment can improve cognitive processing. The purpose of this paper is to present an integrative review of research evidence on the effectiveness of cancer support groups with Asian BC patients. Empirical studies related to support group among Asian and Asian American BC patients published between 1982 and April 2014 are reviewed. There are 15 studies selected (12 from the Asian-Pacific region and 3 from Western countries). The review includes 1 qualitative study, 3 descriptive studies, 1 mixed method design, and 10 experimental or quasi-experimental studies. The support group intervention activities include psycho-educational program such as health education, problem-solving, and stress management. These studies support the effectiveness of support group in alleviating psychological distress and supporting quality of life of Asian BC women. Overall, there is limited research on the use and effectiveness of support groups with Asians cancer patients in Asia and in Western countries. Without accounting for Asian immigrants overseas, the Asian population is expected to grow from 4.3 to 5.3 billion by 2050. As cancer patients become more diverse due to global emigration, more rigorous studies examining the effectiveness of psychosocial intervention among transcultural cancer patients are needed.

How dare you not recognize the role of my contempt? Insight from experimental psychopathology.

PubMed

Grecucci, Alessandro; Frederickson, Jon; Job, Remo

2017-01-01

Gervais & Fessler argue that contempt is an attitude state defined as a lack of respect that potentiates the activation and deactivation of two different clusters of emotions. However, clinical and experimental findings do not support this view. We provide evidence that contempt is not an emotion, nor an attitude, but a reactive defensive mechanism evolved to help individuals avoid shame.

Who Says Your Frames Are Better than Mine? Making the Case for Strategic Framing by Using the Power of Experimental Research

ERIC Educational Resources Information Center

Manuel, Tiffany

2009-01-01

This article details the experimental research on frame effects that provides quantitative evidence that some types of frames have a greater ability to move and affect policy support than others. This method is particularly useful in showing the magnitude by which exposure to alternative ways of thinking about social issues alters the public's…

Effects of Classroom Practices on Reading Comprehension, Engagement, and Motivations for Adolescents

PubMed Central

Guthrie, John T.; Klauda, Susan Lutz

2014-01-01

We investigated the roles of classroom supports for multiple motivations and engagement in students’ informational text comprehension, motivation, and engagement. A composite of classroom contextual variables consisting of instructional support for choice, importance, collaboration, and competence, accompanied by cognitive scaffolding for informational text comprehension, was provided in four-week instructional units for 615 grade 7 students. These classroom motivational-engagement supports were implemented within integrated literacy/history instruction in the Concept-Oriented Reading Instruction (CORI) framework. CORI increased informational text comprehension compared with traditional instruction (TI) in a switching replications experimental design. Students’ perceptions of the motivational-engagement supports were associated with increases in students’ intrinsic motivation, value, perceived competence, and increased positive engagement (dedication) more markedly in CORI than in TI, according to multiple regression analyses. Results extended the evidence for the effectiveness of CORI to literacy/history subject matter and informational text comprehension among middle school students. The experimental effects in classroom contexts confirmed effects from task-specific, situated experimental studies in the literature. PMID:25506087

Effects of Classroom Practices on Reading Comprehension, Engagement, and Motivations for Adolescents.

PubMed

Guthrie, John T; Klauda, Susan Lutz

2014-10-01

We investigated the roles of classroom supports for multiple motivations and engagement in students' informational text comprehension, motivation, and engagement. A composite of classroom contextual variables consisting of instructional support for choice, importance, collaboration, and competence, accompanied by cognitive scaffolding for informational text comprehension, was provided in four-week instructional units for 615 grade 7 students. These classroom motivational-engagement supports were implemented within integrated literacy/history instruction in the Concept-Oriented Reading Instruction (CORI) framework. CORI increased informational text comprehension compared with traditional instruction (TI) in a switching replications experimental design. Students' perceptions of the motivational-engagement supports were associated with increases in students' intrinsic motivation, value, perceived competence, and increased positive engagement (dedication) more markedly in CORI than in TI, according to multiple regression analyses. Results extended the evidence for the effectiveness of CORI to literacy/history subject matter and informational text comprehension among middle school students. The experimental effects in classroom contexts confirmed effects from task-specific, situated experimental studies in the literature.

Pediatric obstructive sleep apnea and the critical role of oral-facial growth: evidences.

PubMed

Huang, Yu-Shu; Guilleminault, Christian

2012-01-01

Review of evidence in support of an oral-facial growth impairment in the development of pediatric sleep apnea in non-obese children. Review of experimental data from infant monkeys with experimentally induced nasal resistance. Review of early historical data in the orthodontic literature indicating the abnormal oral-facial development associated with mouth breathing and nasal resistance. Review of the progressive demonstration of sleep-disordered-breathing (SDB) in children who underwent incomplete treatment of OSA with adenotonsillectomy, and demonstration of abnormal oral-facial anatomy that must often be treated in order for the resolution of OSA. Review of data of long-term recurrence of OSA and indication of oral-facial myofunctional dysfunction in association with the recurrence of OSA. Presentation of prospective data on premature infants and SDB-treated children, supporting the concept of oral-facial hypotonia. Presentation of evidence supporting hypotonia as a primary element in the development of oral-facial anatomic abnormalities leading to abnormal breathing during sleep. Continuous interaction between oral-facial muscle tone, maxillary-mandibular growth and development of SDB. Role of myofunctional reeducation with orthodontics and elimination of upper airway soft tissue in the treatment of non-obese SDB children. Pediatric OSA in non-obese children is a disorder of oral-facial growth.

Effectiveness of a Technology-Based Intervention to Teach Evidence-Based Practice: The EBR Tool.

PubMed

Long, JoAnn D; Gannaway, Paula; Ford, Cindy; Doumit, Rita; Zeeni, Nadine; Sukkarieh-Haraty, Ola; Milane, Aline; Byers, Beverly; Harrison, LaNell; Hatch, Daniel; Brown, Justin; Proper, Sharlan; White, Patricia; Song, Huaxin

2016-02-01

As the world becomes increasingly digital, advances in technology have changed how students access evidence-based information. Research suggests that students overestimate their ability to locate quality online research and lack the skills needed to evaluate the scientific literature. Clinical nurses report relying on personal experience to answer clinical questions rather than searching evidence-based sources. To address the problem, a web-based, evidence-based research (EBR) tool that is usable from a computer, smartphone, or iPad was developed and tested. The purpose of the EBR tool is to guide students through the basic steps needed to locate and critically appraise the online scientific literature while linking users to quality electronic resources to support evidence-based practice (EBP). Testing of the tool took place in a mixed-method, quasi-experimental, and two-population randomized controlled trial (RCT) design in a U.S. and Middle East university. A statistically significant improvement in overall research skills was supported in the quasi-experimental nursing student group and RCT nutrition student group using the EBR tool. A statistically significant proportional difference was supported in the RCT nutrition and PharmD intervention groups in participants' ability to distinguish the credibility of online source materials compared with controls. The majority of participants could correctly apply PICOTS to a case study when using the tool. The data from this preliminary study suggests that the EBR tool enhanced student overall research skills and selected EBP skills while generating data for assessment of learning outcomes. The EBR tool places evidence-based resources at the fingertips of users by addressing some of the most commonly cited barriers to research utilization while exposing users to information and online literacy standards of practice, meeting a growing need within nursing curricula. © 2016 Sigma Theta Tau International.

The Effect of Feedback Delay and Feedback Type on Perceptual Category Learning: The Limits of Multiple Systems

ERIC Educational Resources Information Center

Dunn, John C.; Newell, Ben R.; Kalish, Michael L.

2012-01-01

Evidence that learning rule-based (RB) and information-integration (II) category structures can be dissociated across different experimental variables has been used to support the view that such learning is supported by multiple learning systems. Across 4 experiments, we examined the effects of 2 variables, the delay between response and feedback…

Experimental evidence of a pathogen invasion threshold

PubMed Central

Krkošek, Martin

2018-01-01

Host density thresholds to pathogen invasion separate regions of parameter space corresponding to endemic and disease-free states. The host density threshold is a central concept in theoretical epidemiology and a common target of human and wildlife disease control programmes, but there is mixed evidence supporting the existence of thresholds, especially in wildlife populations or for pathogens with complex transmission modes (e.g. environmental transmission). Here, we demonstrate the existence of a host density threshold for an environmentally transmitted pathogen by combining an epidemiological model with a microcosm experiment. Experimental epidemics consisted of replicate populations of naive crustacean zooplankton (Daphnia dentifera) hosts across a range of host densities (20–640 hosts l−1) that were exposed to an environmentally transmitted fungal pathogen (Metschnikowia bicuspidata). Epidemiological model simulations, parametrized independently of the experiment, qualitatively predicted experimental pathogen invasion thresholds. Variability in parameter estimates did not strongly influence outcomes, though systematic changes to key parameters have the potential to shift pathogen invasion thresholds. In summary, we provide one of the first clear experimental demonstrations of pathogen invasion thresholds in a replicated experimental system, and provide evidence that such thresholds may be predictable using independently constructed epidemiological models. PMID:29410876

Applying evidence to support ethical decisions: is the placebo really powerless?.

PubMed

Porzsolt, Franz; Schlotz-Gorton, Nicole; Biller-Andorno, Nikola; Thim, Anke; Meissner, Karin; Roeckl-Wiedmann, Irmgard; Herzberger, Barbara; Ziegler, Renatus; Gaus, Wilhelm; Pöppe, Ernst

2004-01-01

Using placebos in day-to-day practice is an ethical problem. This paper summarises the available epidemiological evidence to support this difficult decision. Based on these data we propose to differentiate between placebo and "knowledge framing". While the use of placebo should be confined to experimental settings in clinical trials, knowledge framing--which is only conceptually different from placebo--is a desired, expected and necessary component of any doctor-patient encounter. Examples from daily practice demonstrate both, the need to investigate the effects of knowledge framing and its impact on ethical, medical, economical and legal decisions.

The Experimental Evidence in Support of Glycosylation Mechanisms at the SN1-SN2 Interface.

PubMed

Adero, Philip Ouma; Amarasekara, Harsha; Wen, Peng; Bohé, Luis; Crich, David

2018-05-30

A critical review of the state-of-the-art evidence in support of the mechanisms of glycosylation reactions is provided. Factors affecting the stability of putative oxocarbenium ions as intermediates at the S N 1 end of the mechanistic continuum are first surveyed before the evidence, spectroscopic and indirect, for the existence of such species on the time scale of glycosylation reactions is presented. Current models for diastereoselectivity in nucleophilic attack on oxocarbenium ions are then described. Evidence in support of the intermediacy of activated covalent glycosyl donors is reviewed, before the influences of the structure of the nucleophile, of the solvent, of temperature, and of donor-acceptor hydrogen bonding on the mechanism of glycosylation reactions are surveyed. Studies on the kinetics of glycosylation reactions and the use of kinetic isotope effects for the determination of transition-state structure are presented, before computational models are finally surveyed. The review concludes with a critical appraisal of the state of the art.

Mechanisms of Stress-Induced Visceral Pain: Implications in Irritable Bowel Syndrome.

PubMed

Greenwood-Van Meerveld, B; Moloney, R D; Johnson, A C; Vicario, M

2016-08-01

Visceral pain is a term describing pain originating from the internal organs of the body and is a common feature of many disorders, including irritable bowel syndrome (IBS). Stress is implicated in the development and exacerbation of many visceral pain disorders. Recent evidence suggests that stress and the gut microbiota can interact through complementary or opposing factors to influence visceral nociceptive behaviours. The Young Investigator Forum at the International Society of Psychoneuroendocrinology (ISPNE) annual meeting reported experimental evidence suggesting the gut microbiota can affect the stress response to affect visceral pain. Building upon human imaging data showing abnormalities in the central processing of visceral stimuli in patients with IBS and knowledge that the amygdala plays a pivotal role in facilitating the stress axis, the latest experimental evidence supporting amygdala-mediated mechanisms in stress-induced visceral pain was reviewed. The final part of the session at ISPNE reviewed experimental evidence suggesting that visceral pain in IBS may be a result, at least in part, of afferent nerve sensitisation following increases in epithelial permeability and mucosal immune activation. © 2016 British Society for Neuroendocrinology.

Perspective: researching the transition from non-living to the first microorganisms: methods and experiments are major challenges.

PubMed

Trevors, J T

2010-06-01

Methods to research the origin of microbial life are limited. However, microorganisms were the first organisms on the Earth capable of cell growth and division, and interactions with their environment, other microbial cells, and eventually with diverse eukaryotic organisms. The origin of microbial life and the supporting scientific evidence are both an enigma and a scientific priority. Numerous hypotheses have been proposed, scenarios imagined, speculations presented in papers, insights shared, and assumptions made without supporting experimentation, which have led to limited progress in understanding the origin of microbial life. The use of the human imagination to envision the origin of life events, without supporting experimentation, observation and independently replicated experiments required for science, is a significant constraint. The challenge remains how to better understand the origin of microbial life using observations and experimental methods as opposed to speculation, assumptions, scenarios, envisioning events and un-testable hypotheses. This is not an easy challenge as experimental design and plausible hypothesis testing are difficult. Since past approaches have been inconclusive in providing evidence for the origin of microbial life mechanisms and the manner in which genetic instructions was encoded into DNA/RNA, it is reasonable and logical to propose that progress will be made when testable, plausible hypotheses and methods are used in the origin of microbial life research, and the experimental observations are, or are not reproduced in independent laboratories. These perspectives will be discussed in this article as well as the possibility that a pre-biotic film preceded a microbial biofilm as a possible micro-location for the origin of microbial cells capable of growth and division. 2010 Elsevier B.V. All rights reserved.

Trichloroethylene: Mechanistic, epidemiologic and other supporting evidence of carcinogenic hazard.

PubMed

Rusyn, Ivan; Chiu, Weihsueh A; Lash, Lawrence H; Kromhout, Hans; Hansen, Johnni; Guyton, Kathryn Z

2014-01-01

The chlorinated solvent trichloroethylene (TCE) is a ubiquitous environmental pollutant. The carcinogenic hazard of TCE was the subject of a 2012 evaluation by a Working Group of the International Agency for Research on Cancer (IARC). Information on exposures, relevant data from epidemiologic studies, bioassays in experimental animals, and toxicity and mechanism of action studies was used to conclude that TCE is carcinogenic to humans (Group 1). This article summarizes the key evidence forming the scientific bases for the IARC classification. Exposure to TCE from environmental sources (including hazardous waste sites and contaminated water) is common throughout the world. While workplace use of TCE has been declining, occupational exposures remain of concern, especially in developing countries. The strongest human evidence is from studies of occupational TCE exposure and kidney cancer. Positive, although less consistent, associations were reported for liver cancer and non-Hodgkin lymphoma. TCE is carcinogenic at multiple sites in multiple species and strains of experimental animals. The mechanistic evidence includes extensive data on the toxicokinetics and genotoxicity of TCE and its metabolites. Together, available evidence provided a cohesive database supporting the human cancer hazard of TCE, particularly in the kidney. For other target sites of carcinogenicity, mechanistic and other data were found to be more limited. Important sources of susceptibility to TCE toxicity and carcinogenicity were also reviewed by the Working Group. In all, consideration of the multiple evidence streams presented herein informed the IARC conclusions regarding the carcinogenicity of TCE. © 2013.

Trichloroethylene: Mechanistic, Epidemiologic and Other Supporting Evidence of Carcinogenic Hazard

PubMed Central

Rusyn, Ivan; Chiu, Weihsueh A.; Lash, Lawrence H.; Kromhout, Hans; Hansen, Johnni; Guyton, Kathryn Z.

2013-01-01

The chlorinated solvent trichloroethylene (TCE) is a ubiquitous environmental pollutant. The carcinogenic hazard of TCE was the subject of a 2012 evaluation by a Working Group of the International Agency for Research on Cancer (IARC). Information on exposures, relevant data from epidemiologic studies, bioassays in experimental animals, and toxicity and mechanism of action studies was used to conclude that TCE is carcinogenic to humans (Group 1). This article summarizes the key evidence forming the scientific bases for the IARC classification. Exposure to TCE from environmental sources (including from hazardous waste sites and contaminated water) is common throughout the world. While workplace use of TCE has been declining, occupational exposures remain of concern, especially in developing countries. Strongest human evidence is from studies of occupational TCE exposure and kidney cancer. Positive, although less consistent, associations were reported for liver cancer and non-Hodgkin's lymphoma. TCE is carcinogenic at multiple sites in multiple species and strains of experimental animals. The mechanistic evidence includes extensive data on the toxicokinetics and genotoxicity of TCE and its metabolites. Together, available evidence provided a cohesive database supporting the human cancer hazard of TCE, particularly in the kidney. For other target sites of carcinogenicity, mechanistic and other data were found to be more limited. Important sources of susceptibility to TCE toxicity and carcinogenicity were also reviewed by the Working Group. In all, consideration of the multiple evidence streams presented herein informed the IARC conclusions regarding the carcinogenicity of TCE. PMID:23973663

The space shuttle payload planning working groups. Volume 4: Life sciences

NASA Technical Reports Server (NTRS)

1973-01-01

The findings of the Life Sciences working group of the space shuttle payload planning activity are presented. The objectives of the Life Sciences investigations are: (1) to continue the research directed at understanding the origin of life and the search for extraterrestrial evidence of life, (2) biomedical research to understand mechanisms and provide criteria for support of manned flight, (3) technology development for life support, protective systems, and work aids for providing environmental control, and (4) to study basic biological functions at all levels or organization influenced by gravity, radiation, and circadian rhythms. Examples of candidate experimental schedules and the experimental package functional requirements are included.

Improvements in geothermometry. Final technical report. Rev

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

Potter, J.; Dibble, W.; Parks, G.

1982-08-01

Alkali and alkaline earth geothermometers are useful for estimating geothermal reservoir temperatures, though a general theoretical basis has yet to be established and experimental calibration needs improvement. Equilibrium cation exchange between feldspars provided the original basis for the Na-K and Na-K-Ca geothermometers (Fournier and Truesdell, 1973), but theoretical, field and experimental evidence prove that neither equilibrium nor feldspars are necessary. Here, evidence is summarized in support of these observations, concluding that these geothermometers can be expected to have a surprisingly wide range of applicability, but that the reasons behind such broad applicability are not yet understood. Early experimental work provedmore » that water-rock interactions are slow at low temperatures, so experimental calibration at temperatures below 150/sup 0/ is impractical. Theoretical methods and field data were used instead for all work at low temperatures. Experimental methods were emphasized for temperatures above 150/sup 0/C, and the simplest possible solid and solution compositions were used to permit investigation of one process or question at a time. Unexpected results in experimental work prevented complete integration of the various portions of the investigation.« less

Understanding of visual attention by adult humans (Homo sapiens): a partial replication of Povinelli, Bierschwale, and Cech (1999).

PubMed

Thomas, Emily; Murphy, Mary; Pitt, Rebecca; Rivers, Angela; Leavens, David A

2008-11-01

Povinelli, Bierschwale, and Cech (1999) reported that when tested on a visual attention task, the behavior of juvenile chimpanzees did not support a high-level understanding of visual attention. This study replicates their research using adult humans and aims to investigate the validity of their experimental design. Participants were trained to respond to pointing cues given by an experimenter, and then tested on their ability to locate hidden objects from visual cues. Povinelli et al.'s assertion that the generalization of pointing to gaze is indicative of a high-level framework was not supported by our findings: Training improved performance only on initial probe trials when the experimenter's gaze was not directed at the baited cup. Furthermore, participants performed above chance on such trials, the same result exhibited by chimpanzees and used as evidence by Povinelli et al. to support a low-level framework. These findings, together with the high performance of participants in an incongruent condition, in which the experimenter pointed to or gazed at an unbaited container, challenge the validity of their experimental design. (PsycINFO Database Record (c) 2008 APA, all rights reserved).

Brain Opioids and Autism: An Updated Analysis of Possible Linkages.

ERIC Educational Resources Information Center

Sahley, Tony L.; Panksepp, Jaak

1987-01-01

The paper summarizes experimental evidence supporting a neurological theory which posits that autism, at least partially, represents a disruptive overactivation of hypersensitization of neurohormone systems in the brain, such as brain opioids. These substances modulate social-emotional processes. (Author/DB)

COMPLEX MIXTURES OF CHEMICAL CARCINOGENS: PRINCIPLES OF ACTION AND HUMAN CANCER

EPA Science Inventory

There is strong epidemiological evidence supported by experimental animal data that complex environmental mixtures pose a risk to human health producing increases in cancer incidence. Understanding the chemical and biological properties of these mixtures leads to a clearer unde...

Comments on "Ochratoxin A: In utero Exposure in Mice Induces Adducts in Testicular DNA. Toxins 2010, 2, 1428-1444"-Mis-Citation of Rat Literature to Justify a Hypothetical Role for Ochratoxin A in Testicular Cancer.

PubMed

Mantle, Peter G

2010-10-01

A manuscript in the journal recently cited experimental rat data from two manuscripts to support plausibility of a thesis that ochratoxin A might be a cause of human testicular cancer. I believe that there is no experimental evidence that ochratoxin A produces testicular cancer in rats or mice.

Oxytocin and social context moderate social support seeking in women during negative memory recall.

PubMed

Cardoso, Christopher; Valkanas, Helen; Serravalle, Lisa; Ellenbogen, Mark A

2016-08-01

Oxytocin is theorized to promote social support seeking under stress- an alternate biobehavioural response to challenge known as the tend-and-befriend response. These effects may be context dependent, however, and no study has evaluated this effect in the presence and absence of social support. The aim of this study was to evaluate the effects of oxytocin on the experience of recalling emotional autobiographical memories in two contexts-with and without social contact with an experimenter. Sixty-three individuals (32 female) participated in this randomized, double-blind, placebo-controlled, and within-subject study. During recall of negative memories in the absence of social contact, oxytocin decreased perceived emotional support relative to placebo F(1,62)=10.75, p=0.002. In this same context, women who were motivated to affiliate with the experimenter following oxytocin administration showed this effect in greater magnitude t(57)=-2.04, p=0.047, but showed the reverse effect (i.e. increased perceived support in response to oxytocin) when social contact with the experimenter was available t(57)=2.78, p=0.007. Male participants did not evidence this pattern. These findings support the role of oxytocin in social support seeking in distressed women, and highlight the negative consequences of increasing oxytocin bioavailability in the absence of social support. Supportive relationships may be necessary to elicit the prosocial effects oxytocin. Copyright © 2016 Elsevier Ltd. All rights reserved.

New developmental evidence supports a homeotic frameshift of digit identity in the evolution of the bird wing

PubMed Central

2014-01-01

Background The homology of the digits in the bird wing is a high-profile controversy in developmental and evolutionary biology. The embryonic position of the digits cartilages with respect to the primary axis (ulnare and ulna) corresponds to 2, 3, 4, but comparative-evolutionary morphology supports 1, 2, 3. A homeotic frameshift of digit identity in evolution could explain how cells in embryonic positions 2, 3, 4 began developing morphologies 1, 2, 3. Another alternative is that no re-patterning of cell fates occurred, and the primary axis shifted its position by some other mechanism. In the wing, only the anterior digit lacks expression of HoxD10 and HoxD12, resembling digit 1 of other limbs, as predicted by 1, 2, 3. However, upon loss of digit 1 in evolution, the most anterior digit 2 could have lost their expression, deceitfully resembling a digit 1. To test this notion, we observed HoxD10 and HoxD12 in a limb where digit 2 is the most anterior digit: The rabbit foot. We also explored whether early inhibition of Shh signalling in the embryonic wing bud induces an experimental homeotic frameshift, or an experimental axis shift. We tested these hypotheses using DiI injections to study the fate of cells in these experimental wings. Results We found strong transcription of HoxD10 and HoxD12 was present in the most anterior digit 2 of the rabbit foot. Thus, we found no evidence to question the use of HoxD expression as support for 1, 2, 3. When Shh signalling in early wing buds is inhibited, our fate maps demonstrate that an experimental homeotic frameshift is induced. Conclusion Along with comparative morphology, HoxD expression provides strong support for 1, 2, 3 identity of wing digits. As an explanation for the offset 2, 3, 4 embryological position, the homeotic frameshift hypothesis is consistent with known mechanisms of limb development, and further proven to be experimentally possible. In contrast, the underlying mechanisms and experimental plausibility of an axis shift remain unclear. PMID:24725625

New developmental evidence supports a homeotic frameshift of digit identity in the evolution of the bird wing.

PubMed

Salinas-Saavedra, Miguel; Gonzalez-Cabrera, Cristian; Ossa-Fuentes, Luis; Botelho, Joao F; Ruiz-Flores, Macarena; Vargas, Alexander O

2014-04-12

The homology of the digits in the bird wing is a high-profile controversy in developmental and evolutionary biology. The embryonic position of the digits cartilages with respect to the primary axis (ulnare and ulna) corresponds to 2, 3, 4, but comparative-evolutionary morphology supports 1, 2, 3. A homeotic frameshift of digit identity in evolution could explain how cells in embryonic positions 2, 3, 4 began developing morphologies 1, 2, 3. Another alternative is that no re-patterning of cell fates occurred, and the primary axis shifted its position by some other mechanism. In the wing, only the anterior digit lacks expression of HoxD10 and HoxD12, resembling digit 1 of other limbs, as predicted by 1, 2, 3. However, upon loss of digit 1 in evolution, the most anterior digit 2 could have lost their expression, deceitfully resembling a digit 1. To test this notion, we observed HoxD10 and HoxD12 in a limb where digit 2 is the most anterior digit: The rabbit foot. We also explored whether early inhibition of Shh signalling in the embryonic wing bud induces an experimental homeotic frameshift, or an experimental axis shift. We tested these hypotheses using DiI injections to study the fate of cells in these experimental wings. We found strong transcription of HoxD10 and HoxD12 was present in the most anterior digit 2 of the rabbit foot. Thus, we found no evidence to question the use of HoxD expression as support for 1, 2, 3. When Shh signalling in early wing buds is inhibited, our fate maps demonstrate that an experimental homeotic frameshift is induced. Along with comparative morphology, HoxD expression provides strong support for 1, 2, 3 identity of wing digits. As an explanation for the offset 2, 3, 4 embryological position, the homeotic frameshift hypothesis is consistent with known mechanisms of limb development, and further proven to be experimentally possible. In contrast, the underlying mechanisms and experimental plausibility of an axis shift remain unclear.

Clinical Definitions of Melioidosis

PubMed Central

Cheng, Allen C.; Currie, Bart J.; Dance, David A. B.; Funnell, Simon G. P.; Limmathurotsakul, Direk; Simpson, Andrew J. H.; Peacock, Sharon J.

2013-01-01

Clinical definitions of melioidosis and inhalation-acquired melioidosis (Burkholderia pseudomallei infection) are described together with the evidence used to develop these definitions. Such definitions support accurate public health reporting, preparedness planning for deliberate B. pseudomallei release, design of experimental models, and categorization of naturally acquired melioidosis. PMID:23468355

Egocentrism: Its Effect on the Form and Use of Grammar.

ERIC Educational Resources Information Center

Zubin, David A.

The concept of cognitive egocentrism is presented, supported with experimental evidence, and operationally defined on a scale of egocentric distance from "ego" ("speaker") to "hearer," to "other," to "concrete entity." This concept is used in evaluating the hypothesis that the nominative case in…

The Rational-Emotive Approach: A Critique

ERIC Educational Resources Information Center

Morris, G. Barry

1976-01-01

The critique of Rational-Emotive Therapy aims criticism at Ellis' concept of irrationality, analysis of human behavior and therapeutic techniques. Ellis suggests that his critic's claims lack the support of experimental evidence. He further suggests that an "existential" bias pervades which differs from his own brand of…

The Effectiveness of Alternative IEP Dispute Resolution Practices

ERIC Educational Resources Information Center

Scanlon, David; Saenz, Lauren; Kelly, Michael P.

2018-01-01

Alternative Individualized Education Program (IEP) dispute resolution models should respond to limitations of current options. An experimental IEP dispute resolution program provides parents and schools with an evidence-supported neutral perspective on what is needed for free and appropriate education (FAPE) and least restrictive environment…

Filamentary structures in dense plasma focus: Current filaments or vortex filaments?

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

Soto, Leopoldo, E-mail: lsoto@cchen.cl; Pavez, Cristian; Moreno, José

2014-07-15

Recent observations of an azimuthally distributed array of sub-millimeter size sources of fusion protons and correlation between extreme ultraviolet (XUV) images of filaments with neutron yield in PF-1000 plasma focus have re-kindled interest in their significance. These filaments have been described variously in literature as current filaments and vortex filaments, with very little experimental evidence in support of either nomenclature. This paper provides, for the first time, experimental observations of filaments on a table-top plasma focus device using three techniques: framing photography of visible self-luminosity from the plasma, schlieren photography, and interferometry. Quantitative evaluation of density profile of filaments frommore » interferometry reveals that their radius closely agrees with the collision-less ion skin depth. This is a signature of relaxed state of a Hall fluid, which has significant mass flow with equipartition between kinetic and magnetic energy, supporting the “vortex filament” description. This interpretation is consistent with empirical evidence of an efficient energy concentration mechanism inferred from nuclear reaction yields.« less

The Effect of a Supreme Court Decision Regarding Gay Marriage on Social Norms and Personal Attitudes.

PubMed

Tankard, Margaret E; Paluck, Elizabeth Levy

2017-09-01

We propose that institutions such as the U.S. Supreme Court can lead individuals to update their perceptions of social norms, in contrast to the mixed evidence on whether institutions shape individuals' personal opinions. We studied reactions to the June 2015 U.S. Supreme Court ruling in favor of same-sex marriage. In a controlled experimental setting, we found that a favorable ruling, when presented as likely, shifted perceived norms and personal attitudes toward increased support for gay marriage and gay people. Next, a five-wave longitudinal time-series study using a sample of 1,063 people found an increase in perceived social norms supporting gay marriage after the ruling but no change in personal attitudes. This pattern was replicated in a separate between-subjects data set. These findings provide the first experimental evidence that an institutional decision can change perceptions of social norms, which have been shown to guide behavior, even when individual opinions are unchanged.

Determining the bacterial cell biology of Planctomycetes.

PubMed

Boedeker, Christian; Schüler, Margarete; Reintjes, Greta; Jeske, Olga; van Teeseling, Muriel C F; Jogler, Mareike; Rast, Patrick; Borchert, Daniela; Devos, Damien P; Kucklick, Martin; Schaffer, Miroslava; Kolter, Roberto; van Niftrik, Laura; Engelmann, Susanne; Amann, Rudolf; Rohde, Manfred; Engelhardt, Harald; Jogler, Christian

2017-04-10

Bacteria of the phylum Planctomycetes have been previously reported to possess several features that are typical of eukaryotes, such as cytosolic compartmentalization and endocytosis-like macromolecule uptake. However, recent evidence points towards a Gram-negative cell plan for Planctomycetes, although in-depth experimental analysis has been hampered by insufficient genetic tools. Here we develop methods for expression of fluorescent proteins and for gene deletion in a model planctomycete, Planctopirus limnophila, to analyse its cell organization in detail. Super-resolution light microscopy of mutants, cryo-electron tomography, bioinformatic predictions and proteomic analyses support an altered Gram-negative cell plan for Planctomycetes, including a defined outer membrane, a periplasmic space that can be greatly enlarged and convoluted, and an energized cytoplasmic membrane. These conclusions are further supported by experiments performed with two other Planctomycetes, Gemmata obscuriglobus and Rhodopirellula baltica. We also provide experimental evidence that is inconsistent with endocytosis-like macromolecule uptake; instead, extracellular macromolecules can be taken up and accumulate in the periplasmic space through unclear mechanisms.

Perceived Threat Associated with Police Officers and Black Men Predicts Support for Policing Policy Reform

PubMed Central

Skinner, Allison L.; Haas, Ingrid J.

2016-01-01

Racial disparities in policing and recent high-profile incidents resulting in the deaths of Black men have ignited a national debate on policing policies. Given evidence that both police officers and Black men may be associated with threat, we examined the impact of perceived threat on support for reformed policing policies. Across three studies we found correlational evidence that perceiving police officers as threatening predicts increased support for reformed policing practices (e.g., limiting the use of lethal force and matching police force demographics to those of the community). In contrast, perceiving Black men as threatening predicted reduced support for policing policy reform. Perceived threat also predicted willingness to sign a petition calling for police reform. Experimental evidence indicated that priming participants to associate Black men with threat could also reduce support for policing policy reform, and this effect was moderated by internal motivation to respond without prejudice. Priming participants to associate police officers with threat did not increase support for policing policy reform. Results indicate that resistance to policing policy reform is associated with perceiving Black men as threatening. Moreover, findings suggest that publicizing racially charged police encounters, which may conjure associations between Black men and threat, could reduce support for policing policy reform. PMID:27462294

Oxidized methionine is not a prion-specific covalent modification

USDA-ARS?s Scientific Manuscript database

The oxidation of methionine residues in the '-helical region of PrPC has been proposed to be important for prion formation. This proposal has been supported by structural studies, model systems and antibody-based experimental evidence. We developed a sensitive mass spectrometry-based method to stu...

Dietary lycopene and tomato extract supplementations inhibit nonalcoholic steatohepatitis-promoted hepatocarcinogenesis in rats

USDA-ARS?s Scientific Manuscript database

Epidemiological and experimental studies provide supportive evidence that lycopene (LY), a major carotenoid from tomatoes and tomato products, may act as a chemopreventive agent against certain types of cancers. We recently showed that high-fat diet (HFD)-induced nonalcoholic steatohepatitis (NASH) ...

Quasi-experimental study designs series-paper 12: strengthening global capacity for evidence synthesis of quasi-experimental health systems research.

PubMed

Rockers, Peter C; Tugwell, Peter; Grimshaw, Jeremy; Oliver, Sandy; Atun, Rifat; Røttingen, John-Arne; Fretheim, Atle; Ranson, M Kent; Daniels, Karen; Luiza, Vera Lucia; Bärnighausen, Till

2017-09-01

Evidence from quasi-experimental studies is often excluded from systematic reviews of health systems research despite the fact that such studies can provide strong causal evidence when well conducted. This article discusses global coordination of efforts to institutionalize the inclusion of causal evidence from quasi-experiments in systematic reviews of health systems research. In particular, we are concerned with identifying opportunities for strengthening capacity at the global and local level for implementing protocols necessary to ensure that reviews that include quasi-experiments are consistently of the highest quality. We first describe the current state of the global infrastructure that facilitates the production of systematic reviews of health systems research. We identify five important types of actors operating within this infrastructure: review authors; synthesis collaborations that facilitate the review process; synthesis interest groups that supplement the work of the larger collaborations; review funders; and end users, including policymakers. Then, we examine opportunities for intervening to build the capacity of each type of actors to support the inclusion of quasi-experiments in reviews. Finally, we suggest practical next steps for proceeding with capacity building efforts. Because of the complexity and relative nascence of the field, we recommend a carefully planned and executed approach to strengthening global capacity for the inclusion of quasi-experimental studies in systematic reviews. Copyright © 2017 Elsevier Inc. All rights reserved.

Evidence for the Formation of Nitrogen-Rich Platinum and Palladium Nitride Nanoparticles

DOE PAGES

Veith, Gabriel M.; Lupini, Andrew R.; Baggetto, Loïc; ...

2013-12-03

Here, we report evidence for the formation of nitrogen-rich precious metal nanoparticles (Pt, Pd) prepared by reactive sputtering of the pure metal in a N 2 plasma. The composition of the nanoparticles varies as a function of particle size and growth conditions. For the smallest particles the nitrogen content appears to be as high as 6.7 N atoms for each Pd atom or 5.9 N atoms for each Pt atom whereas bulk films have nominal compositions of Pt 7.3N and Pd 2.5N. The nanoparticles are metastable in air and moisture, slowly decomposing over several years. This paper describes the synthesismore » of these materials along with experimental evidence of the composition, oxidation state, and growth modes. Moreover, the catalytic properties of these N-rich nanoparticles were accessed by rotating disk electrode electrochemical studies, the liquid phase oxidation of benzyl alcohol and gas phase CO oxidation and support the experimental evidence for the materials composition.« less

Do behavioral scientists really understand HIV-related sexual risk behavior? A systematic review of longitudinal and experimental studies predicting sexual behavior.

PubMed

Huebner, David M; Perry, Nicholas S

2015-10-01

Behavioral interventions to reduce sexual risk behavior depend on strong health behavior theory. By identifying the psychosocial variables that lead causally to sexual risk, theories provide interventionists with a guide for how to change behavior. However, empirical research is critical to determining whether a particular theory adequately explains sexual risk behavior. A large body of cross-sectional evidence, which has been reviewed elsewhere, supports the notion that certain theory-based constructs (e.g., self-efficacy) are correlates of sexual behavior. However, given the limitations of inferring causality from correlational research, it is essential that we review the evidence from more methodologically rigorous studies (i.e., longitudinal and experimental designs). This systematic review identified 44 longitudinal studies in which investigators attempted to predict sexual risk from psychosocial variables over time. We also found 134 experimental studies (i.e., randomized controlled trials of HIV interventions), but of these only 9 (6.7 %) report the results of mediation analyses that might provide evidence for the validity of health behavior theories in predicting sexual behavior. Results show little convergent support across both types of studies for most traditional, theoretical predictors of sexual behavior. This suggests that the field must expand the body of empirical work that utilizes the most rigorous study designs to test our theoretical assumptions. The inconsistent results of existing research would indicate that current theoretical models of sexual risk behavior are inadequate, and may require expansion or adaptation.

The case against specialized visual-spatial short-term memory.

PubMed

Morey, Candice C

2018-05-24

The dominant paradigm for understanding working memory, or the combination of the perceptual, attentional, and mnemonic processes needed for thinking, subdivides short-term memory (STM) according to whether memoranda are encoded in aural-verbal or visual formats. This traditional dissociation has been supported by examples of neuropsychological patients who seem to selectively lack STM for either aural-verbal, visual, or spatial memoranda, and by experimental research using dual-task methods. Though this evidence is the foundation of assumptions of modular STM systems, the case it makes for a specialized visual STM system is surprisingly weak. I identify the key evidence supporting a distinct verbal STM system-patients with apparent selective damage to verbal STM and the resilience of verbal short-term memories to general dual-task interference-and apply these benchmarks to neuropsychological and experimental investigations of visual-spatial STM. Contrary to the evidence on verbal STM, patients with apparent visual or spatial STM deficits tend to experience a wide range of additional deficits, making it difficult to conclude that a distinct short-term store was damaged. Consistently with this, a meta-analysis of dual-task visual-spatial STM research shows that robust dual-task costs are consistently observed regardless of the domain or sensory code of the secondary task. Together, this evidence suggests that positing a specialized visual STM system is not necessary. (PsycINFO Database Record (c) 2018 APA, all rights reserved).

A convenient method for preparation of 2-amino-4,6-diphenylnicotinonitrile using HBF4 as an efficient catalyst via an anomeric based oxidation: A joint experimental and theoretical study

NASA Astrophysics Data System (ADS)

Zolfigol, Mohammad Ali; Kiafar, Mahya; Yarie, Meysam; Taherpour, Avat(Arman); Fellowes, Thomas; Nicole Hancok, Amber; Yari, Ako

2017-06-01

Experimental and computational studies in the synthesis of 2-amino-4,6-diphenylnicotinonitrile using HBF4 as an oxidizing promoter catalyst under mild and solvent free conditions were carried out. The suggested anomeric based oxidation (ABO) mechanism is supported by experimental and theoretical evidence. The theoretical study shows that the intermediate isomers with 5R- and 5S- chiral positions have suitable structures for the aromatization through an anomeric based oxidation in the final step of the mechanistic pathway.

A systematic review of the evidence for interventions for the prevention and control of meticillin-resistant Staphylococcus aureus (1996-2004): report to the Joint MRSA Working Party (Subgroup A).

PubMed

Loveday, H P; Pellowe, C M; Jones, S R L J; Pratt, R J

2006-05-01

A systematic review was undertaken of the evidence published between 1996 and 2004 on the effectiveness, and associated economic costs, of a range of interventions to prevent and control the transmission of meticillin-resistant Staphylococcus aureus (MRSA) in hospital settings. The review questions focused on screening, patient isolation, use of decolonization strategies, feedback of surveillance data, and environmental hygiene interventions. The reviewers assessed evidence from four recent systematic reviews, 24 non-experimental descriptive studies, five economic evaluations and one recently revised international guideline. The methodological quality of studies retrieved was such that there is currently insufficient high-quality evidence for infection prevention and control interventions in the fields identified for this review. However, evidence from clinically based, non-experimental studies does provide support for the continued use of a range and combination of interventions that contribute to the prevention and control of MRSA within acute hospitals and long-term-care settings. Well-conducted economic evaluations reporting the economic benefits arising from infection prevention and control interventions are lacking.

Effect of subliminal stimuli on consumer behavior: negative evidence.

PubMed

George, S G; Jennings, L B

1975-12-01

The study corrected methodological weaknesses found in previous experiments designed to test the contentions of motivational research theorists that subliminal stimulation can affect buying behavior. The words "Hershey's Chocolate" were presented to a group of 18 experimental Ss below a forced-choice detection threshold. The 19 control Ss had a blank slide superimposed over the same background media. In a highly controlled buying situation neither experimental nor control Ss purchased Hershey's products, but on comparable chocolate products, the experimental Ss bought 5 and the control Ss, 3. A second study tested 15 experimental and 12 control Ss with the stimulus presented just below a recognition threshold. No experimental Ss bought Hershey's; two control Ss did. No support was found for the claims of motivational research theorists.

Effects of suspended sulfates on human health.

PubMed Central

French, J G

1975-01-01

Recent evidence from epidemiologic studies conducted in several areas of the United States shows an association of excess risk of asthmatic attacks with elevated levels of suspended sulfates within specific temperature ranges. These findings are disscussed in the context of experimental animal studies which tend to support these observations. PMID:1157797

Evidence to Support Peer Tutoring Programs at the Undergraduate Level

ERIC Educational Resources Information Center

Colver, Mitchell; Fry, Trevor

2016-01-01

The present study examined undergraduate peer tutoring in three phases. Phase I qualitatively surveyed students' perceptions about the effectiveness of tutoring. Phase II examined the usefulness of promoting regular use of services through a tutoring contract. Phase III utilized an archival, quasi-experimental approach to estimate the effect of…

Ranking mechanical pulps for their potential to photoyellow

Treesearch

Umesh P. Agarwal

2000-01-01

Recently found experimental evidence has provided strong support for an alternative photoyellowing mechanism that suggests that pulp- photoyellowing occurs due to direct photooxidation of hydroquinones (present in mechanical pulps) top-quinones. Because hydroquinones were found to be present in pulps, it may be possible to quantify them. Quantification of mechanical-...

Teacher-to-Parent Communication: Experimental Evidence from a Low-Cost Communication Policy

ERIC Educational Resources Information Center

Kraft, Matthew A.; Rogers, Todd

2014-01-01

A wide body of literature documents the important role that parents play in supporting children's academic success in school (Houtenville & Conway, 2008; Barnard, 2004; Fan & Chen, 2001). Drawing on this literature, national taskforces and federal legislation consistently identify increased parental involvement as a central goal of…

ELECTRORETINOGRAMS ARE ALTERED BY SUBCHRONIC TOLUENE EXPOSURE TO LONG EVANS RATS: EXPERIMENTAL EVIDENCE SUPPORTING OBSERVATIONS FROM STUDIES OF EXPOSED HUMANS

EPA Science Inventory

Impaired visual functions, including low contrast sensitivity and reduced color discrimination, have been reported in studies of humans chronically exposed to several volatile organic solvents. These reports remain controversial, however, in part due to a lack of confirmation fro...

Subchronic Toluene Exposure alters Retinal Function in Long Evans Rats: Experimental Evidence Supporting Observations from Studies of Exposed Humans.

EPA Science Inventory

Studies of humans chronically exposed to volatile organic solvents commonly report impaired visual functions, including low contrast sensitivity and reduced color discrimination. These reports have been controversial, however, in part due to a lack of confirmation from controlled...

Unresolved issues in theories of autoimmune disease using myocarditis as a framework

PubMed Central

Root-Bernstein, Robert; Fairweather, DeLisa

2014-01-01

Many theories of autoimmune disease have been proposed since the discovery that the immune system can attack the body. These theories include the hidden or cryptic antigen theory, modified antigen theory, T cell bypass, T cell-B cell mismatch, epitope spread or drift, the bystander effect, molecular mimicry, anti-idiotype theory, antigenic complementarity, and dual-affinity T cell receptors. We critically review these theories and relevant mathematical models as they apply to autoimmune myocarditis. All theories share the common assumption that autoimmune diseases are triggered by environmental factors such as infections or chemical exposure. Most, but not all, theories and mathematical models are unifactorial assuming single-agent causation of disease. Experimental and clinical evidence and mathematical models exist to support some aspects of most theories, but evidence/models that support one theory almost invariably supports other theories as well. More importantly, every theory (and every model) lacks the ability to account for some key autoimmune disease phenomena such as the fundamental roles of innate immunity, sex differences in disease susceptibility, the necessity for adjuvants in experimental animal models, and the often paradoxical effect of exposure timing and dose on disease induction. We argue that a more comprehensive and integrated theory of autoimmunity associated with new mathematical models is needed and suggest specific experimental and clinical tests for each major theory that might help to clarify how they relate to clinical disease and reveal how theories are related. PMID:25484004

Unresolved issues in theories of autoimmune disease using myocarditis as a framework.

PubMed

Root-Bernstein, Robert; Fairweather, DeLisa

2015-06-21

Many theories of autoimmune disease have been proposed since the discovery that the immune system can attack the body. These theories include the hidden or cryptic antigen theory, modified antigen theory, T cell bypass, T cell-B cell mismatch, epitope spread or drift, the bystander effect, molecular mimicry, anti-idiotype theory, antigenic complementarity, and dual-affinity T cell receptors. We critically review these theories and relevant mathematical models as they apply to autoimmune myocarditis. All theories share the common assumption that autoimmune diseases are triggered by environmental factors such as infections or chemical exposure. Most, but not all, theories and mathematical models are unifactorial assuming single-agent causation of disease. Experimental and clinical evidence and mathematical models exist to support some aspects of most theories, but evidence/models that support one theory almost invariably supports other theories as well. More importantly, every theory (and every model) lacks the ability to account for some key autoimmune disease phenomena such as the fundamental roles of innate immunity, sex differences in disease susceptibility, the necessity for adjuvants in experimental animal models, and the often paradoxical effect of exposure timing and dose on disease induction. We argue that a more comprehensive and integrated theory of autoimmunity associated with new mathematical models is needed and suggest specific experimental and clinical tests for each major theory that might help to clarify how they relate to clinical disease and reveal how theories are related. Copyright © 2014 Elsevier Ltd. All rights reserved.

Comment on “The reduction of friction in long-runout landslides as an emergent phenomenon” by Brandon C. Johnson et al.

USGS Publications Warehouse

Iverson, Richard M.

2016-01-01

Results from a highly idealized, 2-D computational model indicate that dynamic normal-stress rarefactions might cause friction reduction in long-runout landslides, but the physical relevance of the idealized dynamics has not been confirmed by experimental tests. More importantly, the model results provide no evidence that refutes alternative hypotheses about friction reduction mechanisms. One alternative hypothesis, which is strongly supported by field evidence, experimental data, and the predictions of a well-constrained computational model, involves development of high pore fluid pressures in deforming landslide material or overridden bed material. However, no scientific basis exists for concluding that a universal mechanism is responsible for friction reduction in all long-runout landslides.

The effect of low-frequency oscillations on cardio-respiratory synchronization. Observations during rest and exercise

NASA Astrophysics Data System (ADS)

Kenwright, D. A.; Bahraminasab, A.; Stefanovska, A.; McClintock, P. V. E.

2008-10-01

We show that the transitions which occur between close orders of synchronization in the cardiorespiratory system are mainly due to modulation of the cardiac and respiratory processes by low-frequency components. The experimental evidence is derived from recordings on healthy subjects at rest and during exercise. Exercise acts as a perturbation of the system that alters the mean cardiac and respiratory frequencies and changes the amount of their modulation by low-frequency oscillations. The conclusion is supported by numerical evidence based on a model of phase-coupled oscillators, with white noise and lowfrequency noise. Both the experimental and numerical approaches confirm that low-frequency oscillations play a significant role in the transitional behavior between close orders of synchronization.

A realist review of one-to-one breastfeeding peer support experiments conducted in developed country settings.

PubMed

Trickey, Heather; Thomson, Gill; Grant, Aimee; Sanders, Julia; Mann, Mala; Murphy, Simon; Paranjothy, Shantini

2018-01-01

The World Health Organisation guidance recommends breastfeeding peer support (BFPS) as part of a strategy to improve breastfeeding rates. In the UK, BFPS is supported by National Institute for Health and Care Excellence guidance and a variety of models are in use. The experimental evidence for BFPS in developed countries is mixed and traditional methods of systematic review are ill-equipped to explore heterogeneity, complexity, and context influences on effectiveness. This review aimed to enhance learning from the experimental evidence base for one-to-one BFPS intervention. Principles of realist review were applied to intervention case studies associated with published experimental studies. The review aimed (a) to explore heterogeneity in theoretical underpinnings and intervention design for one-to-one BFPS intervention; (b) inform design decisions by identifying transferable lessons developed from cross-case comparison of context-mechanism-outcome relationships; and (c) inform evaluation design by identifying context-mechanism-outcome relationships associated with experimental conditions. Findings highlighted poor attention to intervention theory and considerable heterogeneity in BFPS intervention design. Transferable mid-range theories to inform design emerged, which could be grouped into seven categories: (a) congruence with local infant feeding norms, (b) integration with the existing system of health care, (c) overcoming practical and emotional barriers to access, (d) ensuring friendly, competent, and proactive peers, (e) facilitating authentic peer-mother interactions, (f) motivating peers to ensure positive within-intervention amplification, and (g) ensuring positive legacy and maintenance of gains. There is a need to integrate realist principles into evaluation design to improve our understanding of what forms of BFPS work, for whom and under what circumstances. © 2017 John Wiley & Sons Ltd.

Endocrine-disrupting chemicals and risk of diabetes: an evidence-based review.

PubMed

Lind, P Monica; Lind, Lars

2018-05-09

The purpose of this study was to review the epidemiological and experimental evidence linking background exposure to a selection of environmental endocrine-disrupting chemicals (EDCs) with diabetes and impaired glucose metabolism. The review summarises the literature on both cross-sectional and prospective studies in humans, as well as experimental in vivo and in vitro studies. The findings were subjected to evidence grading according to the Grading of Recommendations Assessment, Development and Evaluation (GRADE) classification. We found >40 cross-sectional and seven prospective studies regarding EDCs and risk of diabetes. Taken together, there is moderate evidence for a relationship between exposure to dichlorodiphenyldichloroethylene (p,p'-DDE), a metabolite of the pesticide dichlorodiphenyltrichloroethane, and diabetes development. Regarding polychlorinated biphenyls (PCBs), it is likely that the rodent models used are not appropriate, and therefore the evidence is poorer than for p,p'-DDE. For other EDCs, such as bisphenol A, phthalates and perfluorinated chemicals, the evidence is scarce, since very few prospective studies exist. Brominated flame retardants do not seem to be associated with a disturbed glucose tolerance. Thus, evidence is accumulating that EDCs might be involved in diabetes development. Best evidence exists for p,p'-DDE. For other chemicals, both prospective studies and supporting animal data are still lacking.

Comments on “Ochratoxin A: In utero Exposure in Mice Induces Adducts in Testicular DNA. Toxins 2010, 2, 1428–1444”—Mis-Citation of Rat Literature to Justify a Hypothetical Role for Ochratoxin A in Testicular Cancer

PubMed Central

Mantle, Peter G.

2010-01-01

A manuscript in the journal recently cited experimental rat data from two manuscripts to support plausibility of a thesis that ochratoxin A might be a cause of human testicular cancer. I believe that there is no experimental evidence that ochratoxin A produces testicular cancer in rats or mice. PMID:22069555

Promoting evidence-based childhood fever management through a peer education programme based on the theory of planned behaviour.

PubMed

Edwards, Helen; Walsh, Anne; Courtney, Mary; Monaghan, Sarah; Wilson, Jenny; Young, Jeanine

2007-10-01

This study examined effectiveness of a theoretically based education programme in reducing inappropriate antipyretic use in fever management. Paediatric nurses' inconsistent, ritualistic antipyretic use in fever management is influenced by many factors including inconsistent beliefs and parental requests. Determinants of antipyretic administration, identified by the theory of planned behaviour, were belief-based attitudes and subjective norms. A quasi-experiment explored group effects of a peer education programme, based on the theory of planned behaviour, on factors influencing paediatric nurses' antipyretic administration. Surveys and chart audits collected data from medical wards at experimental and control hospitals one month pre and one and four months postpeer education programme. All nurses employed in targeted wards were eligible to participate in surveys and all eligible charts were audited. The peer education programme consisted of four one-hour sessions targeting evidence-based knowledge, myths and misconceptions, normative, attitudinal and control influences over and rehearsal of evidence-based fever management. All nurses in experimental hospital targeted wards were eligible to attend. Peer education and support facilitated session information reaching those unable to attend sessions. Two-way univariate anovas explored between subject, experimental and control group and within subject factors, pre, post and latency data. Significant interactions in normative influence (p = 0.01) and intentions (p = 0.01), a significant main group effect in control influence (p = 0.01) and a significant main effect between audit data across time points (p = 0.03) highlight peer education programme effectiveness in behaviour change. Normative, control and intention changes postpeer education programme were maintained in latency data; mean temperature was not. The peer education programme, based on a behaviour change theory, initiated and maintained evidence-based intentions for antipyretics use in fever management. The promotion of evidence-based change in organizational unit intentions and behaviour highlights the crucial role peer support and education can play in continuing educational programmes.

Contextualization: Memory Formation and Retrieval in a Nested Environment

NASA Astrophysics Data System (ADS)

Piefke, Martina; Markowitsch, Hans J.

Episodic memory functions are highly context-dependent. This is true for both experimental and autobiographical episodic memory. We here review neuropsychological and neuroimaging evidence for effects of differential encoding and retrieval contexts on episodic memory performance as well as the underlying neurofunctional mechanisms. In studies of laboratory episodic memory, the influence of context parameters can be assessed by experimental manipulations. Such experiments suggest that contextual variables mainly affect prefrontal functions supporting executive processes involved in episodic learning and retrieval. Context parameters affecting episodic autobiographical memory are far more complex and cannot easily be controlled. Data support the view that not only prefrontal, but also further medial temporal and posterior parietal regions mediating the re-experience and emotional evaluation of personal memories are highly influenced by changing contextual variables of memory encoding and retrieval. Based on our review of available data, we thus suggest that experimental and autobiographical episodic memories are influenced by both overlapping and differential context parameters.

Patent prosecution at the European Patent Office: what is new for life sciences applicants?

PubMed

Lidén, Camilla; Setréus, Ellen

2011-06-01

During the last couple of years, the European Patent Office (EPO) has gradually implemented the so-called 'Raising the Bar' initiative, which is aimed at improving the quality of European patents and, in combination with speeding up the procedure for grant, reducing uncertainty for third parties. As a part of this initiative, a series of changes to the implementing regulations of the European Patent Convention (EPC) were introduced last year. Applicants now need to be sure of their position with regard to supportive experimental data and a thorough argumentation at an earlier stage in the prosecution of a patent application. When evaluating the criteria of inventive step (Art 56 EPC) and sufficiency of disclosure (Art 83 EPC), the EPO frequently refers to two decisions issued by the Boards of Appeal. These decisions are also used to determine whether it is appropriate to further support a disclosed technical effect or a scope of protection with experimental data produced after the date of filing of the patent application. In view of recent case law, it is evident that applicants cannot rely on post-filed experimental data as the only evidence for a technical effect or a certain scope of protection claimed in the application.

Evidence for highly selective neuronal tuning to whole words in the "visual word form area".

PubMed

Glezer, Laurie S; Jiang, Xiong; Riesenhuber, Maximilian

2009-04-30

Theories of reading have posited the existence of a neural representation coding for whole real words (i.e., an orthographic lexicon), but experimental support for such a representation has proved elusive. Using fMRI rapid adaptation techniques, we provide evidence that the human left ventral occipitotemporal cortex (specifically the "visual word form area," VWFA) contains a representation based on neurons highly selective for individual real words, in contrast to current theories that posit a sublexical representation in the VWFA.

Rejection of unfair offers in the ultimatum game is no evidence of strong reciprocity.

PubMed

Yamagishi, Toshio; Horita, Yutaka; Mifune, Nobuhiro; Hashimoto, Hirofumi; Li, Yang; Shinada, Mizuho; Miura, Arisa; Inukai, Keigo; Takagishi, Haruto; Simunovic, Dora

2012-12-11

The strong reciprocity model of the evolution of human cooperation has gained some acceptance, partly on the basis of support from experimental findings. The observation that unfair offers in the ultimatum game are frequently rejected constitutes an important piece of the experimental evidence for strong reciprocity. In the present study, we have challenged the idea that the rejection response in the ultimatum game provides evidence of the assumption held by strong reciprocity theorists that negative reciprocity observed in the ultimatum game is inseparably related to positive reciprocity as the two sides of a preference for fairness. The prediction of an inseparable relationship between positive and negative reciprocity was rejected on the basis of the results of a series of experiments that we conducted using the ultimatum game, the dictator game, the trust game, and the prisoner's dilemma game. We did not find any correlation between the participants' tendencies to reject unfair offers in the ultimatum game and their tendencies to exhibit various prosocial behaviors in the other games, including their inclinations to positively reciprocate in the trust game. The participants' responses to postexperimental questions add support to the view that the rejection of unfair offers in the ultimatum game is a tacit strategy for avoiding the imposition of an inferior status.

Rejection of unfair offers in the ultimatum game is no evidence of strong reciprocity

PubMed Central

Yamagishi, Toshio; Horita, Yutaka; Mifune, Nobuhiro; Hashimoto, Hirofumi; Li, Yang; Shinada, Mizuho; Miura, Arisa; Inukai, Keigo; Takagishi, Haruto; Simunovic, Dora

2012-01-01

The strong reciprocity model of the evolution of human cooperation has gained some acceptance, partly on the basis of support from experimental findings. The observation that unfair offers in the ultimatum game are frequently rejected constitutes an important piece of the experimental evidence for strong reciprocity. In the present study, we have challenged the idea that the rejection response in the ultimatum game provides evidence of the assumption held by strong reciprocity theorists that negative reciprocity observed in the ultimatum game is inseparably related to positive reciprocity as the two sides of a preference for fairness. The prediction of an inseparable relationship between positive and negative reciprocity was rejected on the basis of the results of a series of experiments that we conducted using the ultimatum game, the dictator game, the trust game, and the prisoner’s dilemma game. We did not find any correlation between the participants’ tendencies to reject unfair offers in the ultimatum game and their tendencies to exhibit various prosocial behaviors in the other games, including their inclinations to positively reciprocate in the trust game. The participants’ responses to postexperimental questions add support to the view that the rejection of unfair offers in the ultimatum game is a tacit strategy for avoiding the imposition of an inferior status. PMID:23188801

Evidence for side-chain π-delocalization in a planar substituted benzene: an experimental and theoretical charge density study on 2,5-dimethoxybenzaldehyde thiosemicarbazone.

PubMed

Farrugia, Louis J; Khalaji, Aliakbar Dehno

2011-11-17

The charge density in 2,5-dimethoxybenzaldehyde thiosemicarbazone (1) has been studied experimentally using Mo-K(α) X-ray diffraction at 100 K, and by theory using DFT calculations at the B3LYP/6-311++G(2d,2p) level. The quantum theory of atoms in molecules (QTAIM) was used to investigate the extent of π-delocalization in the thioamide side-chain, which is virtually coplanar with the benzene ring. The experimental and theoretical ellipticity profiles along the bond paths were in excellent agreement, and showed that some of the formal single bonds in the side-chain have significant π-bond character. This view was supported by the magnitudes of the topological bond orders and by the delocalization indices δ(Ω(A), Ω(B)). An orbital decomposition of δ(Ω(A), Ω(B)) demonstrated that there was significant π-character in all the interchain non-H chemical bonds. On the other hand, the source function referenced at the interchain bond critical points could not provide any evidence for π-delocalization, showing instead only limited σ-delocalization between nearest neighbors. Overall, the topological evidence and the atomic graphs of the oxygen atoms did not provide convincing evidence for π-delocalization involving the methoxy substituents.

The Weight of Evidence Does Not Support the Listing of Styrene as “Reasonably Anticipated to be a Human Carcinogen” in NTP's Twelfth Report on Carcinogens

PubMed Central

Rhomberg, Lorenz R.; Goodman, Julie E.; Prueitt, Robyn L.

2013-01-01

Styrene was listed as “reasonably anticipated to be a human carcinogen” in the twelfth edition of the National Toxicology Program's Report on Carcinogens based on what we contend are erroneous findings of limited evidence of carcinogenicity in humans, sufficient evidence of carcinogenicity in experimental animals, and supporting mechanistic data. The epidemiology studies show no consistent increased incidence of, or mortality from, any type of cancer. In animal studies, increased incidence rates of mostly benign tumors have been observed only in certain strains of one species (mice) and at one tissue site (lung). The lack of concordance of tumor incidence and tumor type among animals (even within the same species) and humans indicates that there has been no particular cancer consistently observed among all available studies. The only plausible mechanism for styrene-induced carcinogenesis—a non-genotoxic mode of action that is specific to the mouse lung—is not relevant to humans. As a whole, the evidence does not support the characterization of styrene as “reasonably anticipated to be a human carcinogen,” and styrene should not be listed in the Report on Carcinogens. PMID:23335843

A Systematic Review of Home-Based Childhood Obesity Prevention Studies

PubMed Central

Fawole, Oluwakemi; Segal, Jodi; Wilson, Renee F.; Cheskin, Lawrence J.; Bleich, Sara N.; Wu, Yang; Lau, Brandyn; Wang, Youfa

2013-01-01

BACKGROUND AND OBJECTIVES: Childhood obesity is a global epidemic. Despite emerging research about the role of the family and home on obesity risk behaviors, the evidence base for the effectiveness of home-based interventions on obesity prevention remains uncertain. The objective was to systematically review the effectiveness of home-based interventions on weight, intermediate (eg, diet and physical activity [PA]), and clinical outcomes. METHODS: We searched Medline, Embase, PsychInfo, CINAHL, clinicaltrials.gov, and the Cochrane Library from inception through August 11, 2012. We included experimental and natural experimental studies with ≥1-year follow-up reporting weight-related outcomes and targeting children at home. Two independent reviewers screened studies and extracted data. We graded the strength of the evidence supporting interventions targeting diet, PA, or both for obesity prevention. RESULTS: We identified 6 studies; 3 tested combined interventions (diet and PA), 1 used diet intervention, 1 combined intervention with primary care and consumer health informatics components, and 1 combined intervention with school and community components. Select combined interventions had beneficial effects on fruit/vegetable intake and sedentary behaviors. However, none of the 6 studies reported a significant effect on weight outcomes. Overall, the strength of evidence is low that combined home-based interventions effectively prevent obesity. The evidence is insufficient for conclusions about home-based diet interventions or interventions implemented at home in association with other settings. CONCLUSIONS: The strength of evidence is low to support the effectiveness of home-based child obesity prevention programs. Additional research is needed to test interventions in the home setting, particularly those incorporating parenting strategies and addressing environmental influences. PMID:23753095

Exercise, physical activity, and self-determination theory: A systematic review

PubMed Central

2012-01-01

Background Motivation is a critical factor in supporting sustained exercise, which in turn is associated with important health outcomes. Accordingly, research on exercise motivation from the perspective of self-determination theory (SDT) has grown considerably in recent years. Previous reviews have been mostly narrative and theoretical. Aiming at a more comprehensive review of empirical data, this article examines the empirical literature on the relations between key SDT-based constructs and exercise and physical activity behavioral outcomes. Methods This systematic review includes 66 empirical studies published up to June 2011, including experimental, cross-sectional, and prospective studies that have measured exercise causality orientations, autonomy/need support and need satisfaction, exercise motives (or goal contents), and exercise self-regulations and motivation. We also studied SDT-based interventions aimed at increasing exercise behavior. In all studies, actual or self-reported exercise/physical activity, including attendance, was analyzed as the dependent variable. Findings are summarized based on quantitative analysis of the evidence. Results The results show consistent support for a positive relation between more autonomous forms of motivation and exercise, with a trend towards identified regulation predicting initial/short-term adoption more strongly than intrinsic motivation, and intrinsic motivation being more predictive of long-term exercise adherence. The literature is also consistent in that competence satisfaction and more intrinsic motives positively predict exercise participation across a range of samples and settings. Mixed evidence was found concerning the role of other types of motives (e.g., health/fitness and body-related), and also the specific nature and consequences of introjected regulation. The majority of studies have employed descriptive (i.e., non-experimental) designs but similar results are found across cross-sectional, prospective, and experimental designs. Conclusion Overall, the literature provides good evidence for the value of SDT in understanding exercise behavior, demonstrating the importance of autonomous (identified and intrinsic) regulations in fostering physical activity. Nevertheless, there remain some inconsistencies and mixed evidence with regard to the relations between specific SDT constructs and exercise. Particular limitations concerning the different associations explored in the literature are discussed in the context of refining the application of SDT to exercise and physical activity promotion, and integrating these with avenues for future research. PMID:22726453

Exercise, physical activity, and self-determination theory: a systematic review.

PubMed

Teixeira, Pedro J; Carraça, Eliana V; Markland, David; Silva, Marlene N; Ryan, Richard M

2012-06-22

Motivation is a critical factor in supporting sustained exercise, which in turn is associated with important health outcomes. Accordingly, research on exercise motivation from the perspective of self-determination theory (SDT) has grown considerably in recent years. Previous reviews have been mostly narrative and theoretical. Aiming at a more comprehensive review of empirical data, this article examines the empirical literature on the relations between key SDT-based constructs and exercise and physical activity behavioral outcomes. This systematic review includes 66 empirical studies published up to June 2011, including experimental, cross-sectional, and prospective studies that have measured exercise causality orientations, autonomy/need support and need satisfaction, exercise motives (or goal contents), and exercise self-regulations and motivation. We also studied SDT-based interventions aimed at increasing exercise behavior. In all studies, actual or self-reported exercise/physical activity, including attendance, was analyzed as the dependent variable. Findings are summarized based on quantitative analysis of the evidence. The results show consistent support for a positive relation between more autonomous forms of motivation and exercise, with a trend towards identified regulation predicting initial/short-term adoption more strongly than intrinsic motivation, and intrinsic motivation being more predictive of long-term exercise adherence. The literature is also consistent in that competence satisfaction and more intrinsic motives positively predict exercise participation across a range of samples and settings. Mixed evidence was found concerning the role of other types of motives (e.g., health/fitness and body-related), and also the specific nature and consequences of introjected regulation. The majority of studies have employed descriptive (i.e., non-experimental) designs but similar results are found across cross-sectional, prospective, and experimental designs. Overall, the literature provides good evidence for the value of SDT in understanding exercise behavior, demonstrating the importance of autonomous (identified and intrinsic) regulations in fostering physical activity. Nevertheless, there remain some inconsistencies and mixed evidence with regard to the relations between specific SDT constructs and exercise. Particular limitations concerning the different associations explored in the literature are discussed in the context of refining the application of SDT to exercise and physical activity promotion, and integrating these with avenues for future research.

Experimental Evidence for Diagramming Benefits in Science Writing

ERIC Educational Resources Information Center

Barstow, Brendan; Fazio, Lisa; Schunn, Christian; Ashley, Kevin

2017-01-01

Arguing for the need for a scientific research study (i.e. writing an introduction to a research paper) poses significant challenges for students. When faced with these challenges, students often generate overly safe replications (i.e. fail to find and include opposition to their hypothesis) or in contrast include no strong support for their…

The Beaks of Finches & the Tool Analogy: Use with Care

ERIC Educational Resources Information Center

Milne, Catherine

2008-01-01

Analogies are an integral feature of scientific theories, like evolution. They are developed to support explanations, proposed on the basis of evidence collected from experimental studies, field studies, and other observational studies. They map a known source or process to an unknown or target with the goal of helping educators understand the…

Exploring the Associations among Nutrition, Science, and Mathematics Knowledge for an Integrative, Food-Based Curriculum

ERIC Educational Resources Information Center

Stage, Virginia C.; Kolasa, Kathryn M.; Díaz, Sebastián R.; Duffrin, Melani W.

2018-01-01

Background: Explore associations between nutrition, science, and mathematics knowledge to provide evidence that integrating food/nutrition education in the fourth-grade curriculum may support gains in academic knowledge. Methods: Secondary analysis of a quasi-experimental study. Sample included 438 students in 34 fourth-grade classrooms across…

Drawing conclusions from within-group comparisons and selected subsets of data leads to unsubstantiated conclusions: Letter regarding Malakellis et al.

USDA-ARS?s Scientific Manuscript database

Malakellis et al. conducted an ambitious quasi-experimental evaluation of "multiple initiatives at [the] individual, community, and school policy level to support healthier nutrition and physical activity" among children. In the abstract they concluded, "There was some evidence of effectiveness of t...

The roles of diol epoxide and o-quinone pathways in mouse lung tumorigenesis induced by benzo(a)pyrene: relevance to human lung carcinogenesis

EPA Science Inventory

There is sufficient epidemiological evidence supported by experimental data that some PAH-containing complex environmental mixtures pose risks to human health by increasing lung cancer incidence. The International Agency for Research on Cancer has determined that human respirator...

Dentate Gyrus Is Necessary for Disambiguating Similar Object-Place Representations

ERIC Educational Resources Information Center

Lee, Inah; Solivan, Frances

2010-01-01

Objects are often remembered with their locations, which is an important aspect of event memory. Despite the well-known involvement of the hippocampus in event memory, detailed intrahippocampal mechanisms are poorly understood. In particular, no experimental evidence has been provided in support of the role of the dentate gyrus (DG) in…

Typological Asymmetries in Round Vowel Harmony: Support from Artificial Grammar Learning

ERIC Educational Resources Information Center

Finley, Sara

2012-01-01

Providing evidence for the universal tendencies of patterns in the world's languages can be difficult, as it is impossible to sample all possible languages, and linguistic samples are subject to interpretation. However, experimental techniques, such as artificial grammar learning paradigms, make it possible to uncover the psychological reality of…

Overload retardation due to plasticity-induced crack closure

NASA Technical Reports Server (NTRS)

Fleck, N. A.; Shercliff, H. R.

1989-01-01

Experiments are reported which show that plasticity-induced crack closure can account for crack growth retardation following an overload. The finite element method is used to provide evidence which supports the experimental observations of crack closure. Finally, a simple model is presented which predicts with limited success the retardation transient following an overload.

The principle of superposition in human prehension.

PubMed

Zatsiorsky, Vladimir M; Latash, Mark L; Gao, Fan; Shim, Jae Kun

2004-03-01

The experimental evidence supports the validity of the principle of superposition for multi-finger prehension in humans. Forces and moments of individual digits are defined by two independent commands: "Grasp the object stronger/weaker to prevent slipping" and "Maintain the rotational equilibrium of the object". The effects of the two commands are summed up.

Innovation and a Return to the Status: A Mixed-Methods Study of School Reconstitution

ERIC Educational Resources Information Center

Strunk, Katharine O.; Marsh, Julie A.; Hashim, Ayesha K.; Bush-Mecenas, Susan

2016-01-01

School reconstitution, a turnaround strategy that prescribes massive staffing turnover, is expected to result in more committed and capable school staff and innovative practices. However, little evidence supports this assumption. We use quasi-experimental designs to assess the impact of reconstitution on student achievement and teacher mobility,…

Contingency Contracting and Operant Behavior Change: An Exercise in Applied Behavior Analysis.

ERIC Educational Resources Information Center

Mann, Ronald A.

Until recently, the use of contingency contracting has been largely an issue of theory and discussion with little experimental research evidence gathered to support efficacy. Two major reasons for this problem are suggested and discussed: (1) the concept of contingency contracting has not been adequately defined nor its minimal requirements…

WHEAT LEAF RUST SEVERITY AS AFFECTED BY PLANT DENSITY AND SPECIES PROPORTION IN SIMPLE COMMUNITIES OF WHEAT AND WILD OATS

EPA Science Inventory

While it is generally accepted that dense stands of plants exacerbate epidemics caused by foliar pathogens, there is little experimental evidence to support this view. We grew model plant communities consisting of wheat and wild oats at different densities and proportions and exp...

WHEAT LEAF RUST SEVERITY AS AFFECTED BY PLANT DENSITY AND SPECIES PROPORTION IN SIMPLE COMMUNITIES OF WHEAT AND WILD OATS

EPA Science Inventory

While it is generally accepted that dense stands of plants exacerbate epidermics caused by foliar pathogens, there is little experimental evidence to support this view. We grew model plant communities consisting of wheat and wild oats at different densities and proportions and ex...

New insights into the pathophysiology of post-stroke spasticity.

PubMed

Li, Sheng; Francisco, Gerard E

2015-01-01

Spasticity is one of many consequences after stroke. It is characterized by a velocity-dependent increase in resistance during passive stretch, resulting from hyperexcitability of the stretch reflex. The underlying mechanism of the hyperexcitable stretch reflex, however, remains poorly understood. Accumulated experimental evidence has supported supraspinal origins of spasticity, likely from an imbalance between descending inhibitory and facilitatory regulation of spinal stretch reflexes secondary to cortical disinhibition after stroke. The excitability of reticulospinal (RST) and vestibulospinal tracts (VSTs) has been assessed in stroke survivors with spasticity using non-invasive indirect measures. There are strong experimental findings that support the RST hyperexcitability as a prominent underlying mechanism of post-stroke spasticity. This mechanism can at least partly account for clinical features associated with spasticity and provide insightful guidance for clinical assessment and management of spasticity. However, the possible role of VST hyperexcitability cannot be ruled out from indirect measures. In vivo measure of individual brainstem nuclei in stroke survivors with spasticity using advanced fMRI techniques in the future is probably able to provide direct evidence of pathogenesis of post-stroke spasticity.

New insights into the pathophysiology of post-stroke spasticity

PubMed Central

Li, Sheng; Francisco, Gerard E.

2015-01-01

Spasticity is one of many consequences after stroke. It is characterized by a velocity-dependent increase in resistance during passive stretch, resulting from hyperexcitability of the stretch reflex. The underlying mechanism of the hyperexcitable stretch reflex, however, remains poorly understood. Accumulated experimental evidence has supported supraspinal origins of spasticity, likely from an imbalance between descending inhibitory and facilitatory regulation of spinal stretch reflexes secondary to cortical disinhibition after stroke. The excitability of reticulospinal (RST) and vestibulospinal tracts (VSTs) has been assessed in stroke survivors with spasticity using non-invasive indirect measures. There are strong experimental findings that support the RST hyperexcitability as a prominent underlying mechanism of post-stroke spasticity. This mechanism can at least partly account for clinical features associated with spasticity and provide insightful guidance for clinical assessment and management of spasticity. However, the possible role of VST hyperexcitability cannot be ruled out from indirect measures. In vivo measure of individual brainstem nuclei in stroke survivors with spasticity using advanced fMRI techniques in the future is probably able to provide direct evidence of pathogenesis of post-stroke spasticity. PMID:25914638

Population Demographic History Can Cause the Appearance of Recombination Hotspots

PubMed Central

Johnston, Henry R.; Cutler, David J.

2012-01-01

Although the prevailing view among geneticists suggests that recombination hotspots exist ubiquitously across the human genome, there is only limited experimental evidence from a few genomic regions to support the generality of this claim. A small number of true recombination hotspots are well supported experimentally, but the vast majority of hotspots have been identified on the basis of population genetic inferences from the patterns of linkage disequilibrium (LD) seen in the human population. These inferences are made assuming a particular model of human history, and one of the assumptions of that model is that the effective population size of humans has remained constant throughout our history. Our results show that relaxation of the constant population size assumption can create LD and variation patterns that are qualitatively and quantitatively similar to human populations without any need to invoke localized hotspots of recombination. In other words, apparent recombination hotspots could be an artifact of variable population size over time. Several lines of evidence suggest that the vast majority of hotspots identified on the basis of LD information are unlikely to have elevated recombination rates. PMID:22560089

miRSponge: a manually curated database for experimentally supported miRNA sponges and ceRNAs.

PubMed

Wang, Peng; Zhi, Hui; Zhang, Yunpeng; Liu, Yue; Zhang, Jizhou; Gao, Yue; Guo, Maoni; Ning, Shangwei; Li, Xia

2015-01-01

In this study, we describe miRSponge, a manually curated database, which aims at providing an experimentally supported resource for microRNA (miRNA) sponges. Recent evidence suggests that miRNAs are themselves regulated by competing endogenous RNAs (ceRNAs) or 'miRNA sponges' that contain miRNA binding sites. These competitive molecules can sequester miRNAs to prevent them interacting with their natural targets to play critical roles in various biological and pathological processes. It has become increasingly important to develop a high quality database to record and store ceRNA data to support future studies. To this end, we have established the experimentally supported miRSponge database that contains data on 599 miRNA-sponge interactions and 463 ceRNA relationships from 11 species following manual curating from nearly 1200 published articles. Database classes include endogenously generated molecules including coding genes, pseudogenes, long non-coding RNAs and circular RNAs, along with exogenously introduced molecules including viral RNAs and artificial engineered sponges. Approximately 70% of the interactions were identified experimentally in disease states. miRSponge provides a user-friendly interface for convenient browsing, retrieval and downloading of dataset. A submission page is also included to allow researchers to submit newly validated miRNA sponge data. Database URL: http://www.bio-bigdata.net/miRSponge. © The Author(s) 2015. Published by Oxford University Press.

miRSponge: a manually curated database for experimentally supported miRNA sponges and ceRNAs

PubMed Central

Wang, Peng; Zhi, Hui; Zhang, Yunpeng; Liu, Yue; Zhang, Jizhou; Gao, Yue; Guo, Maoni; Ning, Shangwei; Li, Xia

2015-01-01

In this study, we describe miRSponge, a manually curated database, which aims at providing an experimentally supported resource for microRNA (miRNA) sponges. Recent evidence suggests that miRNAs are themselves regulated by competing endogenous RNAs (ceRNAs) or ‘miRNA sponges’ that contain miRNA binding sites. These competitive molecules can sequester miRNAs to prevent them interacting with their natural targets to play critical roles in various biological and pathological processes. It has become increasingly important to develop a high quality database to record and store ceRNA data to support future studies. To this end, we have established the experimentally supported miRSponge database that contains data on 599 miRNA-sponge interactions and 463 ceRNA relationships from 11 species following manual curating from nearly 1200 published articles. Database classes include endogenously generated molecules including coding genes, pseudogenes, long non-coding RNAs and circular RNAs, along with exogenously introduced molecules including viral RNAs and artificial engineered sponges. Approximately 70% of the interactions were identified experimentally in disease states. miRSponge provides a user-friendly interface for convenient browsing, retrieval and downloading of dataset. A submission page is also included to allow researchers to submit newly validated miRNA sponge data. Database URL: http://www.bio-bigdata.net/miRSponge. PMID:26424084

Homolytic Cleavage of a B-B Bond by the Cooperative Catalysis of Two Lewis Bases: Computational Design and Experimental Verification.

PubMed

Wang, Guoqiang; Zhang, Honglin; Zhao, Jiyang; Li, Wei; Cao, Jia; Zhu, Chengjian; Li, Shuhua

2016-05-10

Density functional theory (DFT) investigations revealed that 4-cyanopyridine was capable of homolytically cleaving the B-B σ bond of diborane via the cooperative coordination to the two boron atoms of the diborane to generate pyridine boryl radicals. Our experimental verification provides supportive evidence for this new B-B activation mode. With this novel activation strategy, we have experimentally realized the catalytic reduction of azo-compounds to hydrazine derivatives, deoxygenation of sulfoxides to sulfides, and reduction of quinones with B2 (pin)2 at mild conditions. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Early-Life Nutritional Programming of Type 2 Diabetes: Experimental and Quasi-Experimental Evidence.

PubMed

Vaiserman, Alexander M

2017-03-05

Consistent evidence from both experimental and human studies suggest that inadequate nutrition in early life can contribute to risk of developing metabolic disorders including type 2 diabetes (T2D) in adult life. In human populations, most findings supporting a causative relationship between early-life malnutrition and subsequent risk of T2D were obtained from quasi-experimental studies ('natural experiments'). Prenatal and/or early postnatal exposures to famine were demonstrated to be associated with higher risk of T2D in many cohorts around the world. Recent studies have highlighted the importance of epigenetic regulation of gene expression as a possible major contributor to the link between the early-life famine exposure and T2D in adulthood. Findings from these studies suggest that prenatal exposure to the famine may result in induction of persistent epigenetic changes that have adaptive significance in postnatal development but can predispose to metabolic disorders including T2D at the late stages of life. In this review, quasi-experimental data on the developmental programming of T2D are summarized and recent research findings on changes in DNA methylation that mediate these effects are discussed.

Gender-specific effects of early nutritional restriction on adult obesity risk: evidence from quasi-experimental studies.

PubMed

Robinson, Whitney R

2012-12-01

In countries undergoing nutrition transition and historically poor minority groups in wealthy countries, obesity tends to be more common in women than men. A potential contributor to this female excess of obesity is a mismatch between perinatal nutritional restriction and a later calorie-rich environment. Several epidemiologic and quasi-experimental studies support a gender-differential effect of early nutritional deprivation on adult obesity. The quasi-experimental studies are of particular interest because results of quasi-experimental studies are typically less vulnerable to confounding bias than observational studies. Four quasi-experimental studies-exploiting 20th century famines that occurred in Europe, Africa, and Asia-provide evidence that perinatal nutritional restriction followed by relative caloric abundance may increase adult obesity risk to a greater extent in women than men. If the findings are accurate and generalizable to contemporary food environments, they suggest that the female offspring of poor, or otherwise nutritionally restricted, women in rapidly developing and wealthy countries may be at particularly high risk of adult obesity. Research into gender-specific effects of early life nutritional deprivation and its interactions with later environmental exposures may provide insight into global gender differences in obesity prevalence.

Early-Life Nutritional Programming of Type 2 Diabetes: Experimental and Quasi-Experimental Evidence

PubMed Central

Vaiserman, Alexander M.

2017-01-01

Consistent evidence from both experimental and human studies suggest that inadequate nutrition in early life can contribute to risk of developing metabolic disorders including type 2 diabetes (T2D) in adult life. In human populations, most findings supporting a causative relationship between early-life malnutrition and subsequent risk of T2D were obtained from quasi-experimental studies (‘natural experiments’). Prenatal and/or early postnatal exposures to famine were demonstrated to be associated with higher risk of T2D in many cohorts around the world. Recent studies have highlighted the importance of epigenetic regulation of gene expression as a possible major contributor to the link between the early-life famine exposure and T2D in adulthood. Findings from these studies suggest that prenatal exposure to the famine may result in induction of persistent epigenetic changes that have adaptive significance in postnatal development but can predispose to metabolic disorders including T2D at the late stages of life. In this review, quasi-experimental data on the developmental programming of T2D are summarized and recent research findings on changes in DNA methylation that mediate these effects are discussed. PMID:28273874

Methodological individualism in experimental games: not so easily dismissed.

PubMed

Krueger, Joachim I

2008-06-01

Orthodox game theory and social preference models cannot explain why people cooperate in many experimental games or how they manage to coordinate their choices. The theory of evidential decision making provides a solution, based on the idea that people tend to project their own choices onto others, whatever these choices might be. Evidential decision making preserves methodological individualism, and it works without recourse to social preferences. Rejecting methodological individualism, team reasoning is a thinly disguised resurgence of the group mind fallacy, and the experiments reported by Colman et al. [Colman, A. M., Pulford, B. D., & Rose, J. (this issue). Collective rationality in interactive decisions: Evidence for team reasoning. Acta Psychologica, doi:10.1016/j.actpsy.2007.08.003.] do not offer evidence that uniquely supports team reasoning.

A critical review of RHIC experimental results

NASA Astrophysics Data System (ADS)

Trainor, Thomas A.

2014-07-01

The relativistic heavy-ion collider (RHIC) was constructed to achieve an asymptotic state of nuclear matter in heavy-ion collisions, a near-ideal gas of deconfined quarks and gluons denoted quark-gluon plasma or QGP. RHIC collisions are indeed very different from the hadronic processes observed at the Bevalac and AGS, but high-energy elementary-collision mechanisms are also non-hadronic. The two-component model (TCM) combines measured properties of elementary collisions with the Glauber eikonal model to provide an alternative asymptotic limit for A-A collisions. RHIC data have been interpreted to indicate formation of a strongly-coupled QGP (sQGP) or "perfect liquid". In this review, I consider the experimental evidence that seems to support such conclusions and alternative evidence that may conflict with those conclusions and suggest different interpretations.

Properties and mechanisms of immunoglobulins for congenital cytomegalovirus disease.

PubMed

Parruti, Giustino; Polilli, Ennio; Ursini, Tamara; Tontodonati, Monica

2013-12-01

Immunoglobulins are one major component of adaptive immunity to external and resident microorganisms, evolving very early in phylogenesis. They help eukaryotes in controlling infections, mainly through their neutralizing activity, which quenches both the cytopathic and inflammatory potential of invading microorganisms. Cytomegalovirus (CMV)-related disease is generally blunted in seropositive subjects with conserved specific humoral responses. CMV-seropositive pregnant women, in accordance with such evidence, suffer little or no fetal damage when reexposed to CMV. Several seminal experiences and early experimental models confirmed that repeated infusions of immunoglobulins, either with hyperimmune or standard preparations, may help to reduce maternal-fetal CMV transmission, as well as to quench fetal disease upon transmission. This review focused on experimental evidence supporting the potential role of immunoglobulins as a tool to control fetal CMV-related disease in pregnant women.

Cognitive Contributions to Gait and Falls: Evidence and Implications

PubMed Central

Amboni, Marianna; Barone, Paolo; Hausdorff, Jeffrey M.

2014-01-01

Dementia and gait impairments often coexist in older adults and patients with neurodegenerative disease. Both conditions represent independent risk factors for falls. The relationship between cognitive function and gait has recently received increasing attention. Gait is no longer considered merely automated motor activity but rather an activity that requires executive function and attention as well as judgment of external and internal cues. In this review, we intend to: (1) summarize and synthesize the experimental, neuropsychological, and neuroimaging evidence that supports the role played by cognition in the control of gait; and (2) briefly discuss the implications deriving from the interplay between cognition and gait. In recent years, the dual task paradigm has been widely used as an experimental method to explore the interplay between gait and cognition. Several neuropsychological investigations have also demonstrated that walking relies on the use of several cognitive domains, including executive-attentional function, visuospatial abilities, and even memory resources. A number of morphological and functional neuroimaging studies have offered additional evidence supporting the relationship between gait and cognitive resources. Based on the findings from 3 lines of studies, it appears that a growing body of evidence indicates a pivotal role of cognition in gait control and fall prevention. The interplay between higher-order neural function and gait has a number of clinical implications, ranging from integrated assessment tools to possible innovative lines of interventions, including cognitive therapy for falls prevention on one hand and walking program for reducing dementia risk on the other. PMID:24132840

A systematic review of the utility of antidepressant pharmacotherapy in the treatment of vulvodynia pain.

PubMed

Leo, Raphael J; Dewani, Seema

2013-10-01

  Antidepressants have often been recommended as a potential treatment for the management of vulvodynia. However, review of the evidence supporting this recommendation has not been systematically assessed.   To evaluate the efficacy of antidepressant pharmacotherapy in the treatment of vulvodynia.   An assessment of the methodological quality of published reports addressing the utility of antidepressants in the treatment of vulvodynia was undertaken. Several secondary outcomes generated in the existing literature were also examined.   A comprehensive search of the available literature was conducted.   The search yielded 13 published reports, i.e., 2 randomized controlled trials, 1 quasi-experimental trial, 7 non-experimental studies, and 3 case reports. A number of methodological shortcomings were identified in several of the reports with respect to study design including lack of clear inclusion/exclusion criteria, small sample sizes, lack of comparison groups, insufficient blinding, among others. The vast majority of studies utilized tricyclic antidepressants (TCAs). Evidence supporting the benefits of TCAs studied to date was limited, i.e., based largely upon descriptive reports but unsubstantiated by randomized controlled trials. There were no systematic investigations into the comparative efficacy of different antidepressant classes in the treatment of vulvodynia.   There is insufficient evidence to support the recommendation of antidepressant pharmacotherapy in the treatment of vulvodynia. Although some vulvodynia-afflicted patients derive symptom relief from antidepressants, additional research is required to identify those characteristics that would predict those patients for whom antidepressants are more likely to be effective. © 2012 International Society for Sexual Medicine.

Monte Carlo simulations support non-Cerenkov radioluminescence production in tissue

NASA Astrophysics Data System (ADS)

Ackerman, Nicole L.; Boschi, Federico; Spinelli, Antonello E.

2017-08-01

There is experimental evidence for the production of non-Cerenkov radioluminescence in a variety of materials, including tissue. We constructed a Geant4 Monte Carlo simulation of the radiation from P32 and Tc99m interacting in chicken breast and used experimental imaging data to model a scintillation-like emission. The same radioluminescence spectrum is visible from both isotopes and cannot otherwise be explained through fluorescence or filter miscalibration. We conclude that chicken breast has a near-infrared scintillation-like response with a light yield three orders of magnitude smaller than BGO.

Parasitic Helminths: New Weapons against Immunological Disorders

PubMed Central

Osada, Yoshio; Kanazawa, Tamotsu

2010-01-01

The prevalence of allergic and autoimmune diseases is increasing in developed countries, possibly due to reduced exposure to microorganisms in childhood (hygiene hypothesis). Epidemiological and experimental evidence in support of this hypothesis is accumulating. In this context, parasitic helminths are now important candidates for antiallergic/anti-inflammatory agents. Here we summarize antiallergic/anti-inflammatory effects of helminths together along with our own study of the effects of Schistosoma mansoni on Th17-dependent experimental arthritis. We also discuss possible mechanisms of helminth-induced suppression according to the recent advances of immunology. PMID:20169100

Parasitic helminths: new weapons against immunological disorders.

PubMed

Osada, Yoshio; Kanazawa, Tamotsu

2010-01-01

The prevalence of allergic and autoimmune diseases is increasing in developed countries, possibly due to reduced exposure to microorganisms in childhood (hygiene hypothesis). Epidemiological and experimental evidence in support of this hypothesis is accumulating. In this context, parasitic helminths are now important candidates for antiallergic/anti-inflammatory agents. Here we summarize antiallergic/anti-inflammatory effects of helminths together along with our own study of the effects of Schistosoma mansoni on Th17-dependent experimental arthritis. We also discuss possible mechanisms of helminth-induced suppression according to the recent advances of immunology.

Surface tension driven flow in glass melts and model fluids

NASA Technical Reports Server (NTRS)

Mcneil, T. J.; Cole, R.; Subramanian, R. S.

1982-01-01

Surface tension driven flow has been investigated analytically and experimentally using an apparatus where a free column of molten glass or model fluids was supported at its top and bottom faces by solid surfaces. The glass used in the experiments was sodium diborate, and the model fluids were silicone oils. In both the model fluid and glass melt experiments, conclusive evidence was obtained to prove that the observed flow was driven primarily by surface tension forces. The experimental observations are in qualitative agreement with predictions from the theoretical model.

Enhancing the gene-environment interaction framework through a quasi-experimental research design: evidence from differential responses to September 11.

PubMed

Fletcher, Jason M

2014-01-01

This article uses a gene-environment interaction framework to examine the differential responses to an objective external stressor based on genetic variation in the production of depressive symptoms. This article advances the literature by utilizing a quasi-experimental environmental exposure design, as well as a regression discontinuity design, to control for seasonal trends, which limit the potential for gene-environment correlation and allow stronger causal claims. Replications are attempted for two prominent genes (5-HTT and MAOA), and three additional genes are explored (DRD2, DRD4, and DAT1). This article provides evidence of a main effect of 9/11 on reports of feelings of sadness and fails to replicate a common finding of interaction using 5-HTT but does show support for interaction with MAOA in men. It also provides new evidence that variation in the DRD4 gene modifies an individual's response to the exposure, with individuals with no 7-repeats found to have a muted response.

Characteristics and development of necrophylatic periderms in mature bark of American beech

Treesearch

William D. Ostrofsky; Robert O. Blanchard

1983-01-01

Investigations were made of necrophylactic peridems which were found to delimit natural and experimentally induced cankers in American beech. Anatomical evidence is presented which supports the hypothesis that the necrophylactic periderm is generated from recent derivatives of the vascular cambium as well as from living cells of the bark tissues present at the time of...

The principle of superposition in human prehension

PubMed Central

Zatsiorsky, Vladimir M.; Latash, Mark L.; Gao, Fan; Shim, Jae Kun

2010-01-01

SUMMARY The experimental evidence supports the validity of the principle of superposition for multi-finger prehension in humans. Forces and moments of individual digits are defined by two independent commands: “Grasp the object stronger/weaker to prevent slipping” and “Maintain the rotational equilibrium of the object”. The effects of the two commands are summed up. PMID:20186284

A Longitudinal Study of the Association between Violent Video Game Play and Aggression among Adolescents

ERIC Educational Resources Information Center

Willoughby, Teena; Adachi, Paul J. C.; Good, Marie

2012-01-01

In the past 2 decades, correlational and experimental studies have found a positive association between violent video game play and aggression. There is less evidence, however, to support a long-term relation between these behaviors. This study examined sustained violent video game play and adolescent aggressive behavior across the high school…

Nutritional Management in Enterocutaneous Fistula. What is the evidence?

PubMed Central

BADRASAWI, Manal; SHAHAR, Suzana; SAGAP, Ismail

2015-01-01

The management of Enterocutaneous fistula (ECF) is challenging. It remains associated with morbidity and mortality, despite advancements in medical and surgical therapies. Early nutritional support using parenteral, enteral or fystuloclysis routs is essential to reverse catabolism and replace nutrients, fluid and electrolyte losses. This study aims to review the current literature on the management of ECF. Fistulae classifications have an impact on the calories and protein requirements. Early nutritional support with parenteral, enteral nutrition or fistuloclysis played a significant role in the management outcome. Published literature on the nutritional management of ECF is mostly retrospective and lacks experimental design. Prospective studies do not investigate nutritional assessment or management experimentally. Individualising the nutritional management protocol was recommended due to the absence of management guidelines for ECF patients. PMID:26715903

Topical Atropine in the Control of Myopia

PubMed Central

GALVIS, Virgilio; TELLO, Alejandro; PARRA, M. Margarita; MERAYO-LLOVES, Jesus; LARREA, Jaime; JULIAN RODRIGUEZ, Carlos; CAMACHO, Paul Anthony

2016-01-01

Atropine has been used for more than a century to arrest myopia progression. Compelling evidence of its protective effect has been reported in well-designed clinical studies, mainly performed during the last two decades. However, its exact mechanism of action has not been determined. Experimental findings have shown that the mechanism is not related to accommodation, as was thought for decades. A review of the published literature revealed a significant amount of evidence supporting its safety and efficacy at a concentration of 1.0%, and at lower concentrations (as low as 0.01%). PMID:28293653

Phytoplankton defence mechanisms: traits and trade-offs.

PubMed

Pančić, Marina; Kiørboe, Thomas

2018-05-01

In aquatic ecosystems, unicellular algae form the basis of the food webs. Theoretical and experimental studies have demonstrated that one of the mechanisms that maintain high diversity of phytoplankton is through predation and the consequent evolution of defence mechanisms. Proposed defence mechanisms in phytoplankton are diverse and include physiological (e.g. toxicity, bioluminescence), morphological (e.g. silica shell, colony formation), and behavioural (e.g. escape response) traits. However, the function of many of the proposed defence mechanisms remains elusive, and the costs and benefits (trade-offs) are often unquantified or undocumented. Here, we provide an overview of suggested phytoplankton defensive traits and review their experimental support. Wherever possible we quantify the trade-offs from experimental evidence and theoretical considerations. In many instances, experimental evidence suggests that defences are costless. However, we argue that (i) some costs materialize only under natural conditions, for example, sinking losses, or dependency on the availability of specific nutrients, and (ii) other costs become evident only under resource-deficient conditions where a rivalry for limiting resources between growth and defence occurs. Based on these findings, we suggest two strategies for quantifying the costs of defence mechanisms in phytoplankton: (i) for the evaluation of defence costs that are realized under natural conditions, a mechanistic understanding of the hypothesized component processes is required; and (ii) the magnitude of the costs (i.e. growth reduction) must be assessed under conditions of resource limitation. © 2018 Cambridge Philosophical Society.

Impact of discharge planning decision support on time to readmission among older adult medical patients.

PubMed

Bowles, Kathryn H; Hanlon, Alexandra; Holland, Diane; Potashnik, Sheryl L; Topaz, Maxim

2014-01-01

Hospital clinicians are overwhelmed with the volume of patients churning through the health care systems. The study purpose was to determine whether alerting case managers about high-risk patients by supplying decision support results in better discharge plans as evidenced by time to first hospital readmission. Four medical units at one urban, university medical center. A quasi-experimental study including a usual care and experimental phase with hospitalized English-speaking patients aged 55 years and older. The intervention included using an evidence-based screening tool, the Discharge Decision Support System (D2S2), that supports clinicians' discharge referral decision making by identifying high-risk patients upon admission who need a referral for post-acute care. The usual care phase included collection of the D2S2 information, but not sharing the information with case managers. The experimental phase included data collection and then sharing the results with the case managers. The study compared time to readmission between index discharge date and 30 and 60 days in patients in both groups (usual care vs. experimental). After sharing the D2S2 results, the percentage of referral or high-risk patients readmitted by 30 and 60 days decreased by 6% and 9%, respectively, representing a 26% relative reduction in readmissions for both periods. Supplying decision support to identify high-risk patients recommended for postacute referral is associated with better discharge plans as evidenced by an increase in time to first hospital readmission. The tool supplies standardized information upon admission allowing more time to work with high-risk admissions.

Secondary school physics teachers' conceptions of scientific evidence: A collective case study

NASA Astrophysics Data System (ADS)

Taylor, Joseph A.

Engaging secondary school students in inquiry-oriented tasks that more closely simulate the scholarly activities of scientists has been recommended as a way to improve scientific literacy. Two tasks that are frequently recommended include students' design of original experiments, and students' evaluation of scientific evidence and conclusions. Yet, little is known about teachers' conceptions of experimentation. The principal aim of this study, therefore, was to describe the nature of prospective and practicing physics teachers' conceptions of scientific evidence. More specifically, the following research questions guided this study: (1) What types of issues related to the measurement reliability and experimental validity of scientific evidence do practicing and prospective physics teachers think about when designing experiments? (2) When presented with hypothetical scenarios that describe unsound experimental procedures or poorly supported conclusions (or both), what concerns will prospective and practicing physics teachers raise? And (3) When the participants' responses to parallel research prompts are compared across protocols, what similarities and differences exist? The nature of the teacher-participants' conceptions was described from an analysis of data collected from research prompts such as interviews and hand written artifacts. In these research prompts, the teachers "thought aloud" while designing experiments and critically evaluated student-collected evidence presented in hypothetical classroom scenarios. The data from this study suggested that the three teachers, while contemplating the reliability and validity of scientific evidence, frequently used their conceptions of evidence in conjunction with specific subject matter conceptions. The data also indicated that the relationship between subject matter knowledge and conceptions of evidence was more pronounced for some conceptions of evidence than for others. Suggestions for future research included conducting similar studies in other physics content areas as well as other scientific disciplines. Implications for science teacher education suggested that science and science methods courses encourage the construction of evidence-based arguments, as well as engagement in peer review and critique.

Dietary phytochemicals and cancer chemoprevention: a review of the clinical evidence

PubMed Central

Kotecha, Ritesh; Takami, Akiyoshi; Espinoza, J. Luis

2016-01-01

Cancer chemoprevention involves the use of different natural or biologic agents to inhibit or reverse tumor growth. Epidemiological and pre-clinical data suggest that various natural phytochemicals and dietary compounds possess chemopreventive properties, and in-vitro and animal studies support that these compounds may modulate signaling pathways involved in cell proliferation and apoptosis in transformed cells, enhance the host immune system and sensitize malignant cells to cytotoxic agents. Despite promising results from experimental studies, only a limited number of these compounds have been tested in clinical trials and have shown variable results. In this review, we summarize the data regarding select phytochemicals including curcumin, resveratrol, lycopene, folates and tea polyphenols with emphasis on the clinical evidence supporting the efficacy of these compounds in high-risk populations. PMID:27232756

Dietary phytochemicals and cancer chemoprevention: a review of the clinical evidence.

PubMed

Kotecha, Ritesh; Takami, Akiyoshi; Espinoza, J Luis

2016-08-09

Cancer chemoprevention involves the use of different natural or biologic agents to inhibit or reverse tumor growth. Epidemiological and pre-clinical data suggest that various natural phytochemicals and dietary compounds possess chemopreventive properties, and in-vitro and animal studies support that these compounds may modulate signaling pathways involved in cell proliferation and apoptosis in transformed cells, enhance the host immune system and sensitize malignant cells to cytotoxic agents. Despite promising results from experimental studies, only a limited number of these compounds have been tested in clinical trials and have shown variable results. In this review, we summarize the data regarding select phytochemicals including curcumin, resveratrol, lycopene, folates and tea polyphenols with emphasis on the clinical evidence supporting the efficacy of these compounds in high-risk populations.

Are we failing young people not in employment, education or training (NEETs)? A systematic review and meta-analysis of re-engagement interventions.

PubMed

Mawn, Lauren; Oliver, Emily J; Akhter, Nasima; Bambra, Clare L; Torgerson, Carole; Bridle, Chris; Stain, Helen J

2017-01-25

Youth comprise 40% of the world's unemployed, a status associated with adverse wellbeing and social, health, and economic costs. This systematic review and meta-analysis review synthesises the literature on the effectiveness of interventions targeting young people not in employment, education, or training (NEET). Randomised and quasi-randomised trials with a concurrent or counterfactual control group and baseline equivalence are included. Cochrane collaboration tools are used to assess quality, and a narrative synthesis was undertaken. The primary outcome is employment; secondary outcomes were health, earnings, welfare receipt, and education. Eighteen trials are included (9 experimental and 9 quasi-experimental), sample sizes range from 32 to 54,923. Interventions include social skills, vocational, or educational classroom-based training, counselling or one-to-one support, internships, placements, on-the-job or occupational training, financial incentives, case management, and individual support. Meta-analysis of three high-quality trials demonstrates a 4% (CI 0.0-0.7) difference between intervention and control groups on employment. Evidence for other outcomes lacks consistency; however, more intensive programmes increase employment and wages over the longer term. There is some evidence that intensive multi-component interventions effectively decrease unemployment amongst NEETs. The quality of current evidence is limited, leaving policy makers under-served when designing and implementing new programmes, and a vulnerable population neglected. PROSPERO CRD42014007535.

Income Mobility Breeds Tolerance for Income Inequality: Cross-National and Experimental Evidence.

PubMed

Shariff, Azim F; Wiwad, Dylan; Aknin, Lara B

2016-05-01

American politicians often justify income inequality by referencing the opportunities people have to move between economic stations. Though past research has shown associations between income mobility and resistance to wealth redistribution policies, no experimental work has tested whether perceptions of mobility influence tolerance for inequality. In this article, we present a cross-national comparison showing that income mobility is associated with tolerance for inequality and experimental work demonstrating that perceptions of higher mobility directly affect attitudes toward inequality. We find support for both the prospect of upward mobility and the view that peoples' economic station is the product of their own efforts, as mediating mechanisms. © The Author(s) 2016.

A patient centered care plan in the EHR: improving collaboration and engagement.

PubMed

Chunchu, Kavitha; Mauksch, Larry; Charles, Carol; Ross, Valerie; Pauwels, Judith

2012-09-01

Patients attempting to manage their chronic conditions require ongoing support in changing and adopting self-management behaviors. However, patient values, health goals, and action plans are not well represented in the electronic health record (EHR) impeding the ability of the team (MA and providers) to provide respectful, ongoing self-management support. We evaluated whether a team approach to using an EHR based patient centered care plan (PCCP) improved collaborative self-management planning. An experimental, prospective cohort study was conducted in a family medicine residency clinic. The experimental group included 7 physicians and a medical assistant who received 2 hr of PCCP training. The control group consisted of 7 physicians and a medical assistant. EHR charts were analyzed for evidence of 8 behavior change elements. Follow-up interviews with experimental group patients and physicians and the medical assistant assessed their experiences. We found that PCCP charts had more documented behavior change elements than control charts in all 8 domains (p < .001). Experimental group physicians valued the PCCP model and suggested ways to improve its use. Patient feedback demonstrated support for the model. A PCCP can help team members to engage patients with chronic illnesses in goal setting and action planning to support self-management. An EHR design that stores patient values, health goals, and action plans may strengthen continuity and quality of care between patients and primary care team members. (PsycINFO Database Record (c) 2012 APA, all rights reserved).

Alliance-focused therapy for anorexia nervosa: integrative relational and behavioral change treatments in a single-case experimental design.

PubMed

Satir, Dana A; Goodman, David M; Shingleton, Rebecca M; Porcerelli, John H; Gorman, Bernard S; Pratt, Elizabeth M; Barlow, David H; Thompson-Brenner, Heather

2011-12-01

Evidence supporting outpatient treatments for anorexia nervosa (AN) is severely lacking, due to low retention and poor outcome. One explanation for drop-out is weak treatment alliances. A single-case experimental analysis accompanied by in-depth qualitative description is presented for Ms. O, who received a novel treatment for AN called Alliance Focused Treatment (AFT) that attends to ruptures in the alliance, interpersonal difficulties and emotional avoidance. At intake Ms. O met diagnostic criteria for AN, Major Depressive Disorder, and Social Phobia. She was characterized as having symptoms of Obsessive Compulsive, Avoidant, and Depressive personality disorders. Treatment began with a Baseline followed by the experimental (AFT) and comparison treatments (Behavioral Change Treatment [BCT]) using a replicated experimental single-case phase change design. Graphs of slopes of kilocalorie and alliance change facilitated observation of treatment effects. Ms. O participated in 16 sessions of AFT and 8 sessions of BCT with specific benefits. Ratings of the treatment alliance were consistently high and she evidenced significant changes in weight, quality of life, and personality pathology. Associations between rupture/repair episodes and kilocalorie increases were observed. The utility of the treatment relationship in facilitating emotional expression was evident. At posttreatment, Ms. O endorsed cognitive AN symptoms, although these were not explicitly treated. This study provides preliminary support for the feasibility and effect of AFT and BCT, and highlights the importance of the alliance in treating adults with AN. Further research on emotion regulation in AN and its effect on the treatment relationship are needed.

Weight-of-evidence evaluation of short-term ozone exposure and cardiovascular effects.

PubMed

Goodman, Julie E; Prueitt, Robyn L; Sax, Sonja N; Lynch, Heather N; Zu, Ke; Lemay, Julie C; King, Joseph M; Venditti, Ferdinand J

2014-10-01

There is a relatively large body of research on the potential cardiovascular (CV) effects associated with short-term ozone exposure (defined by EPA as less than 30 days in duration). We conducted a weight-of-evidence (WoE) analysis to assess whether it supports a causal relationship using a novel WoE framework adapted from the US EPA's National Ambient Air Quality Standards causality framework. Specifically, we synthesized and critically evaluated the relevant epidemiology, controlled human exposure, and experimental animal data and made a causal determination using the same categories proposed by the Institute of Medicine report Improving the Presumptive Disability Decision-making Process for Veterans ( IOM 2008). We found that the totality of the data indicates that the results for CV effects are largely null across human and experimental animal studies. The few statistically significant associations reported in epidemiology studies of CV morbidity and mortality are very small in magnitude and likely attributable to confounding, bias, or chance. In experimental animal studies, the reported statistically significant effects at high exposures are not observed at lower exposures and thus not likely relevant to current ambient ozone exposures in humans. The available data also do not support a biologically plausible mechanism for CV effects of ozone. Overall, the current WoE provides no convincing case for a causal relationship between short-term exposure to ambient ozone and adverse effects on the CV system in humans, but the limitations of the available studies preclude definitive conclusions regarding a lack of causation. Thus, we categorize the strength of evidence for a causal relationship between short-term exposure to ozone and CV effects as "below equipoise."

Systematic review of power mobility outcomes for infants, children and adolescents with mobility limitations.

PubMed

Livingstone, Roslyn; Field, Debra

2014-10-01

To summarize and critically appraise the evidence related to power mobility use in children (18 years or younger) with mobility limitations. Searches were performed in 12 electronic databases along with hand searching for articles published in English to September 2012 and updated February 2014. The search was restricted to quantitative studies including at least one child with a mobility limitation and measuring an outcome related to power mobility device use. Articles were appraised using American Academy of Cerebral Palsy and Developmental Medicine (AACPDM) criteria for group and single-subject designs. The PRISMA statement was followed with inclusion criteria set a priori. Two reviewers independently screened titles, abstracts and full-text articles. AACPDM quality ratings were completed for levels I-III studies. Of 259 titles, 29 articles met inclusion criteria, describing 28 primary research studies. One study, rated as strong level II evidence, supported positive impact of power mobility on overall development as well as independent mobility. Another study, rated as moderate level III evidence, supported positive impact on self-initiated movement. Remaining studies, rated evidence levels IV and V, provided support for a positive impact on a broad range of outcomes from to International Classification of Functioning (ICF) components of body structure and function, activity and participation. Some studies suggest that environmental factors may be influential in successful power mobility use and skill development. The body of evidence supporting outcomes for children using power mobility is primarily descriptive rather than experimental in nature, suggesting research in this area is in its infancy. © The Author(s) 2014.

Experimental support for an immunological approach to the search for life on other planets.

PubMed

Schweitzer, Mary Higby; Wittmeyer, Jennifer; Avci, Recep; Pincus, Seth

2005-02-01

We propose a three-phase approach to test for evidence of life in extraterrestrial samples. The approach capitalizes on the flexibility, sensitivity, and specificity of antibody-antigen interactions. Data are presented to support the first phase, in which various extraction protocols are compared for efficiency, and in which a preliminary suite of antibodies are tested against various antigens. The antigens and antibodies were chosen on the basis of criteria designed to optimize the detection of extraterrestrial biomarkers unique to living or once-living organisms.

A Literary Review of One Versus Two Factor Theories of Learning as the Issue Relates to Operant Conditioning of the Autonomic Nervous System.

ERIC Educational Resources Information Center

Christ, Susann

This paper reviews several issues regarding one- versus two-factor theories of learning. First, the traditional distinctions between classical and operant conditioning are presented. This includes both theoretical and experimental contrasts. Second, empirical evidence in support for a one-factor theory is examined. Numerous research studies…

Antioxidant Cerium Oxide Nanoparticles in Biology and Medicine

PubMed Central

Nelson, Bryant C.; Johnson, Monique E.; Walker, Marlon L.; Riley, Kathryn R.; Sims, Christopher M.

2016-01-01

Previously, catalytic cerium oxide nanoparticles (CNPs, nanoceria, CeO2-x NPs) have been widely utilized for chemical mechanical planarization in the semiconductor industry and for reducing harmful emissions and improving fuel combustion efficiency in the automobile industry. Researchers are now harnessing the catalytic repertoire of CNPs to develop potential new treatment modalities for both oxidative- and nitrosative-stress induced disorders and diseases. In order to reach the point where our experimental understanding of the antioxidant activity of CNPs can be translated into useful therapeutics in the clinic, it is necessary to evaluate the most current evidence that supports CNP antioxidant activity in biological systems. Accordingly, the aims of this review are three-fold: (1) To describe the putative reaction mechanisms and physicochemical surface properties that enable CNPs to both scavenge reactive oxygen species (ROS) and to act as antioxidant enzyme-like mimetics in solution; (2) To provide an overview, with commentary, regarding the most robust design and synthesis pathways for preparing CNPs with catalytic antioxidant activity; (3) To provide the reader with the most up-to-date in vitro and in vivo experimental evidence supporting the ROS-scavenging potential of CNPs in biology and medicine. PMID:27196936

Viral infections and breast cancer - A current perspective.

PubMed

Gannon, O M; Antonsson, A; Bennett, I C; Saunders, N A

2018-04-28

Sporadic human breast cancer is the most common cancer to afflict women. Since the discovery, decades ago, of the oncogenic mouse mammary tumour virus, there has been significant interest in the potential aetiologic role of infectious agents in sporadic human breast cancer. To address this, many studies have examined the presence of viruses (e.g. papillomaviruses, herpes viruses and retroviruses), endogenous retroviruses and more recently, microbes, as a means of implicating them in the aetiology of human breast cancer. Such studies have generated conflicting experimental and clinical reports of the role of infection in breast cancer. This review evaluates the current evidence for a productive oncogenic viral infection in human breast cancer, with a focus on the integration of sensitive and specific next generation sequencing technologies with pathogen discovery. Collectively, the majority of the recent literature using the more powerful next generation sequencing technologies fail to support an oncogenic viral infection being involved in disease causality in breast cancer. In balance, the weight of the current experimental evidence supports the conclusion that viral infection is unlikely to play a significant role in the aetiology of breast cancer. Copyright © 2018 Elsevier B.V. All rights reserved.

Evidence that monkeys (Macaca tonkeana and Sapajus apella) read moves, but no evidence that they read goals.

PubMed

Costes-Thiré, Morgane; Levé, Marine; Uhlrich, Pierre; Pasquaretta, Cristian; De Marco, Arianna; Thierry, Bernard

2015-08-01

Whereas most experiments indicate that monkeys have no theory of mind, a study carried out by Wood and collaborators (2007) claimed that they can make inferences about the intentions of another individual. We applied the experimental procedure devised by these authors to investigate whether monkeys can recognize goal-directed actions. We tested 16 Tonkean macaques (Macaca tonkeana) and 12 tufted capuchin monkeys (Sapajus apella). Each subject was submitted to 24 trials in randomized order. The experimenter presented 2 containers, 1 of which was potentially baited with a food reward. After the experimenter had either intentionally or accidentally made an action on 1 of the containers, the subject was asked to select 1 of them. We found that individuals in both species failed to distinguish between accidental and intentional actions. However, they displayed a significant preference for the container touched by the experimenter in the hand conditions, and not in the elbow conditions. These results do not support those reported by Wood and collaborators, but they are consistent with other studies concluding that monkeys are not capable of mind reading. (c) 2015 APA, all rights reserved).

Optimization of life support systems and their systems reliability

NASA Technical Reports Server (NTRS)

Fan, L. T.; Hwang, C. L.; Erickson, L. E.

1971-01-01

The identification, analysis, and optimization of life support systems and subsystems have been investigated. For each system or subsystem that has been considered, the procedure involves the establishment of a set of system equations (or mathematical model) based on theory and experimental evidences; the analysis and simulation of the model; the optimization of the operation, control, and reliability; analysis of sensitivity of the system based on the model; and, if possible, experimental verification of the theoretical and computational results. Research activities include: (1) modeling of air flow in a confined space; (2) review of several different gas-liquid contactors utilizing centrifugal force: (3) review of carbon dioxide reduction contactors in space vehicles and other enclosed structures: (4) application of modern optimal control theory to environmental control of confined spaces; (5) optimal control of class of nonlinear diffusional distributed parameter systems: (6) optimization of system reliability of life support systems and sub-systems: (7) modeling, simulation and optimal control of the human thermal system: and (8) analysis and optimization of the water-vapor eletrolysis cell.

Cancer immunotherapy by immunosuppression.

PubMed

Prehn, Richmond T; Prehn, Liisa M

2010-12-15

We have previously suggested that the stimulatory effect of a weak immune reaction on tumor growth may be necessary for the growth of incipient tumors. In the present paper, we enlarge upon and extend that idea by collecting evidence in the literature bearing upon the new hypothesis that a growing cancer, whether in man or mouse, is throughout its lifespan, probably growing and progressing because of continued immune stimulation by a weak immune reaction. We also suggest that prolonged immunosuppression might interfere with progression and thus be an aid to therapy. While most of the considerable evidence that supports the hypothesis comes from observations of experimental mouse tumors, there is suggestive evidence that human tumors may behave in much the same way, and as far as we can ascertain, there is no present evidence that necessarily refutes the hypothesis.

Effectiveness of Student Learning during Experimental Work in Primary School.

PubMed

Logar, Ana; Peklaj, Cirila; Ferk Savec, Vesna

2017-09-01

The aim of the research was to optimize the effectiveness of student learning based on experimental work in chemistry classes in Slovenian primary schools. To obtain evidence about how experimental work is implemented during regular chemistry classes, experimental work was videotaped during 19 units of chemistry lessons at 12 Slovenian primary schools from the pool of randomly selected schools. Altogether 332 eight-grade students were involved in the investigation, with an average age of 14.2 years. Students were videotaped during chemistry lessons, and their worksheets were collected afterward. The 12 chemistry teachers, who conducted lessons in these schools, were interviewed before the lessons; their teaching plans were also collected. The collected data was analyzed using qualitative methods. The results indicate that many teachers in Slovenian primary schools are not fully aware of the potential of experimental work integrated into chemistry lessons for the development of students' experimental competence. Further research of the value of different kinds of training to support teachers for the use of experimental work in chemistry teaching is needed.

Improving evidence based practice in postgraduate nursing programs: A systematic review: Bridging the evidence practice gap (BRIDGE project).

PubMed

Hickman, Louise D; DiGiacomo, Michelle; Phillips, Jane; Rao, Angela; Newton, Phillip J; Jackson, Debra; Ferguson, Caleb

2018-04-01

The nursing profession has a significant evidence to practice gap in an increasingly complex and dynamic health care environment. To evaluate effectiveness of teaching and learning strategies related to a capstone project within a Masters of Nursing program that encourage the development of evidence based practice capabilities. Systematic review that conforms to the PRISMA statement. Master's Nursing programs that include elements of a capstone project within a university setting. MEDLINE, CINAHL, Cochrane Database of Systematic Reviews, ERIC and PsycInfo were used to search for RCT's or quasi experimental studies conducted between 1979 and 9 June 2017, published in a peer reviewed journal in English. Of 1592 studies, no RCT's specifically addressed the development of evidence based practice capabilities within the university teaching environment. Five quasi-experimental studies integrated blended learning, guided design processes, small group work, role play and structured debate into Masters of Nursing research courses. All five studies demonstrated some improvements in evidence based practice skills and/or research knowledge translation, with three out of five studies demonstrating significant improvements. There is a paucity of empirical evidence supporting the best strategies to use in developing evidence based practice skills and/or research knowledge translation skills for Master's Nursing students. As a profession, nursing requires methodologically robust studies that are discipline specific to identify the best approaches for developing evidence-based practice skills and/or research knowledge translation skills within the university teaching environment. Provision of these strategies will enable the nursing profession to integrate the best empirical evidence into nursing practice. Copyright © 2018. Published by Elsevier Ltd.

Experimental study on local scouring at pile-supported piers

NASA Astrophysics Data System (ADS)

Moreno, Mario; Birjukova, Olga; Grimaldi, Carmelo; Gaudio, Roberto; Cardoso, António H.

2017-06-01

In spite of the increasing importance of complex piers for bridges, the number of studies on these piers is comparatively small and the predictors of scour depth at complex piers are only a few, derived from limited experimental evidence. The main purpose of this paper is to share with the hydraulics community the results of 67 tests on scouring at pile-supported piers (including complex piers) aligned with the flow, under clear-water conditions close to the threshold of beginning of sediment motion, while contributing to shade some more light on the influence of the pile-cap thickness on the equilibrium scour depth, the reliability of the superposition approach, the contribution of each one of the complex pier components to the equilibrium scour depth of the ensemble, and the performance of existing predictors of local scour at complex piers.

Denial of service to same-sex and interracial couples: Evidence from a national survey experiment.

PubMed

Powell, Brian; Schnabel, Landon; Apgar, Lauren

2017-12-01

Legislatures and courts are debating whether businesses can deny services to same-sex couples for religious reasons. Yet, little is known about public views on this issue. In a national survey experiment, Americans ( n = 2035) responded to an experimental vignette describing a gay or interracial couple refused service. Vignettes varied the reason for refusal (religion/nonreligious) and by business type (individual/corporation). Results confirm greater support of service refusal by the self-employed than by corporations and to gay couples than to interracial couples. However, religious reasons for refusal to gay couples elicit no more support than do nonreligious reasons. In the first national study to experimentally analyze views on service refusal to sexual minorities, we demonstrate that views vary by several factors but not by whether the refusal was for religious reasons.

How Social Preferences Shape Incentives in (Experimental) Markets for Credence Goods.

PubMed

Kerschbamer, Rudolf; Sutter, Matthias; Dulleck, Uwe

2017-03-01

Credence goods markets suffer from inefficiencies caused by superior information of sellers about the surplus-maximising quality. While standard theory predicts that equal mark-up prices solve the credence goods problem if customers can verify the quality received, experimental evidence indicates the opposite. We identify a lack of robustness with respect to heterogeneity in social preferences as a possible cause of this and conduct new experiments that allow for parsimonious identification of sellers' social preference types. Our results confirm the assumed heterogeneity in social preferences and provide strong support for our explanation of the failure of verifiability to increase efficiency.

Delayed School Start Times and Adolescent Sleep: A Systematic Review of the Experimental Evidence

PubMed Central

Minges, Karl E.; Redeker, Nancy S.

2016-01-01

Summary Many schools have instituted later morning start times to improve sleep, academic, and other outcomes in response to the mismatch between youth circadian rhythms and early morning start times. However, there has been no systematic synthesis of the evidence on the effects of this practice. To examine the impact of delayed school start time on students’ sleep, health, and academic outcomes, electronic databases were systematically searched and data were extracted using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Six studies satisfied selection criteria and used pre-post, no control (n=3), randomized controlled trial (n=2), and quasi-experimental (n=1) designs. School start times were delayed 25 to 60 minutes, and correspondingly, total sleep time increased from 25 to 77 minutes per weeknight. Some studies revealed reduced daytime sleepiness, depression, caffeine use, tardiness to class, and trouble staying awake. Overall, the evidence supports recent non-experimental study findings and calls for policy that advocates for delayed school start time to improve sleep. This presents a potential long-term solution to chronic sleep restriction during adolescence. However, there is a need for rigorous randomized study designs and reporting of consistent outcomes, including objective sleep measures and consistent measures of health and academic performance. PMID:26545246

Theory-Based Formative Research on an Anti-Cyberbullying Victimization Intervention Message.

PubMed

Savage, Matthew W; Deiss, Douglas M; Roberto, Anthony J; Aboujaoude, Elias

2017-02-01

Cyberbullying is a common byproduct of the digital revolution with serious consequences to victims. Unfortunately, there is a dearth of empirically based methods to confront it. This study used social cognitive theory to design and test an intervention message aimed at persuading college students to abstain from retaliation, seek social support, save evidence, and notify authorities-important victim responses identified and recommended in previous research. Using a posttest-only control group design, this study tested the effectiveness of an intervention message in changing college students' perceived susceptibility to and perceived severity of cyberbullying as well as their self-efficacy, response efficacy, attitudes, and behavioral intentions toward each recommended response in future episodes of cyberbullying. Results indicated that the intervention message caused participants in the experimental condition to report significantly higher susceptibility, but not perceived severity, to cyberbullying than those in the control condition. The intervention message also caused expected changes in all outcomes except self-efficacy for not retaliating and in all outcomes for seeking social support, saving evidence, and notifying an authority. Implications for message design and future research supporting evidence-based anti-cyberbullying health communication campaigns are discussed.

Decision making by urgency gating: theory and experimental support.

PubMed

Thura, David; Beauregard-Racine, Julie; Fradet, Charles-William; Cisek, Paul

2012-12-01

It is often suggested that decisions are made when accumulated sensory information reaches a fixed accuracy criterion. This is supported by many studies showing a gradual build up of neural activity to a threshold. However, the proposal that this build up is caused by sensory accumulation is challenged by findings that decisions are based on information from a time window much shorter than the build-up process. Here, we propose that in natural conditions where the environment can suddenly change, the policy that maximizes reward rate is to estimate evidence by accumulating only novel information and then compare the result to a decreasing accuracy criterion. We suggest that the brain approximates this policy by multiplying an estimate of sensory evidence with a motor-related urgency signal and that the latter is primarily responsible for neural activity build up. We support this hypothesis using human behavioral data from a modified random-dot motion task in which motion coherence changes during each trial.

A fractal model for nuclear organization: current evidence and biological implications

PubMed Central

Bancaud, Aurélien; Lavelle, Christophe; Huet, Sébastien; Ellenberg, Jan

2012-01-01

Chromatin is a multiscale structure on which transcription, replication, recombination and repair of the genome occur. To fully understand any of these processes at the molecular level under physiological conditions, a clear picture of the polymorphic and dynamic organization of chromatin in the eukaryotic nucleus is required. Recent studies indicate that a fractal model of chromatin architecture is consistent with both the reaction-diffusion properties of chromatin interacting proteins and with structural data on chromatin interminglement. In this study, we provide a critical overview of the experimental evidence that support a fractal organization of chromatin. On this basis, we discuss the functional implications of a fractal chromatin model for biological processes and propose future experiments to probe chromatin organization further that should allow to strongly support or invalidate the fractal hypothesis. PMID:22790985

On Closed Shells in Nuclei

DOE R&D Accomplishments Database

Mayer, M. G.

1948-02-01

It has been suggested in the past that special numbers of neutrons or protons in the nucleus form a particularly stable configuration.{sup1} The complete evidence for this has never been summarized, nor is it generally recognized how convincing this evidence is. That 20 neutrons or protons (Ca{sup40}) form a closed shell is predicted by the Hartree model. A number of calculations support this fact.{sup2} These considerations will not be repeated here. In this paper, the experimental facts indicating a particular stability of shells of 50 and 82 protons and of 50, 82, and 126 neutrons will be listed.

Putting Thought in Accordance with Things: The Demise of Animal-Based Analogies for Plant Functions

NASA Astrophysics Data System (ADS)

Barker, Miles

Scientists' attempts to understand plant functions by ascribing animal functions to plants - the analogist tradition, derived from Aristotle - began to be superseded in Europe by an experimentalist tradition in the seventeenth century. In classrooms today, science students learning about plant functions (exemplified here by the topic of transpiration) face a parallel dilemma: the pitching of their own habitual mental processes of analogy building (enhanced by the suggestive morphology of plants)and the persuasiveness of everyday language (for example, about plants and water)against the new experimental evidence presented by the teacher. In the case oftranspiration, six practical suggestions whereby teachers can support students in thisstruggle to put their thoughts (especially everyday mental models) in accordance withthings (classroom experimental evidence) are advanced. The wider implications forhow we teach about Living Things, and how we view the status of analogies in sciencegenerally, are discussed.

Evidence of Adaptive Evolutionary Divergence during Biological Invasion

PubMed Central

Lucek, Kay; Sivasundar, Arjun; Seehausen, Ole

2012-01-01

Rapid phenotypic diversification during biological invasions can either arise by adaptation to alternative environments or by adaptive phenotypic plasticity. Where experimental evidence for adaptive plasticity is common, support for evolutionary diversification is rare. Here, we performed a controlled laboratory experiment using full-sib crosses between ecologically divergent threespine stickleback populations to test for a genetic basis of adaptation. Our populations are from two very different habitats, lake and stream, of a recently invaded range in Switzerland and differ in ecologically relevant morphological traits. We found that in a lake-like food treatment lake fish grow faster than stream fish, resembling the difference among wild type individuals. In contrast, in a stream-like food treatment individuals from both populations grow similarly. Our experimental data suggest that genetically determined diversification has occurred within less than 140 years after the arrival of stickleback in our studied region. PMID:23152900

Robotics: The next step?

PubMed

Broeders, Ivo A M J

2014-02-01

Robotic systems were introduced 15 years ago to support complex endoscopic procedures. The technology is increasingly used in gastro-intestinal surgery. In this article, literature on experimental- and clinical research is reviewed and ergonomic issues are discussed. literature review was based on Medline search using a large variety of search terms, including e.g. robot(ic), randomized, rectal, oesophageal, ergonomics. Review articles on relevant topics are discussed with preference. There is abundant evidence of supremacy in performing complex endoscopic surgery tasks when using the robot in an experimental setting. There is little high-level evidence so far on translation of these merits to clinical practice. Robotic systems may appear helpful in complex gastro-intestinal surgery. Moreover, dedicated computer based technology integrated in telepresence systems opens the way to integration of planning, diagnostics and therapy. The first high tech add-ons such as near infrared technology are under clinical evaluation. Copyright © 2014 Elsevier Ltd. All rights reserved.

Tocopherols in cancer: an update

PubMed Central

Gupta, Soumyasri Das; Suh, Nanjoo

2016-01-01

Tocopherols exist in four forms designated as α, β, δ and γ. Due to their strong antioxidant properties, tocopherols have been suggested to reduce the risk of cancer. Cancer prevention studies with tocopherols have mostly utilized α-tocopherol. Large scale clinical trials with α-tocopherol provided inconsistent results regarding the cancer preventive activities of tocopherols. This review summarizes our current understanding of the anti-cancer activities of different forms of tocopherols based on follow up of the clinical trials, recent epidemiological evidences and experimental studies using in vitro and in vivo models. The experimental data provide strong evidence in support of the anti-cancer activities of δ-tocopherol,γ-tocopherol and the natural tocopherol mixture rich in γ-tocopherol, γ-TmT, over α-tocopherol. Such outcomes emphasize the need for detailed investigation into the cancer preventive activities of different forms of tocopherols to provide a strong rationale for intervention studies in the future. PMID:26751721

Direct Cytoskeleton Forces Cause Membrane Softening in Red Blood Cells

PubMed Central

Rodríguez-García, Ruddi; López-Montero, Iván; Mell, Michael; Egea, Gustavo; Gov, Nir S.; Monroy, Francisco

2015-01-01

Erythrocytes are flexible cells specialized in the systemic transport of oxygen in vertebrates. This physiological function is connected to their outstanding ability to deform in passing through narrow capillaries. In recent years, there has been an influx of experimental evidence of enhanced cell-shape fluctuations related to metabolically driven activity of the erythroid membrane skeleton. However, no direct observation of the active cytoskeleton forces has yet been reported to our knowledge. Here, we show experimental evidence of the presence of temporally correlated forces superposed over the thermal fluctuations of the erythrocyte membrane. These forces are ATP-dependent and drive enhanced flickering motions in human erythrocytes. Theoretical analyses provide support for a direct force exerted on the membrane by the cytoskeleton nodes as pulses of well-defined average duration. In addition, such metabolically regulated active forces cause global membrane softening, a mechanical attribute related to the functional erythroid deformability. PMID:26083919

Extraction of Pharmacokinetic Evidence of Drug–Drug Interactions from the Literature

PubMed Central

Kolchinsky, Artemy; Lourenço, Anália; Wu, Heng-Yi; Li, Lang; Rocha, Luis M.

2015-01-01

Drug-drug interaction (DDI) is a major cause of morbidity and mortality and a subject of intense scientific interest. Biomedical literature mining can aid DDI research by extracting evidence for large numbers of potential interactions from published literature and clinical databases. Though DDI is investigated in domains ranging in scale from intracellular biochemistry to human populations, literature mining has not been used to extract specific types of experimental evidence, which are reported differently for distinct experimental goals. We focus on pharmacokinetic evidence for DDI, essential for identifying causal mechanisms of putative interactions and as input for further pharmacological and pharmacoepidemiology investigations. We used manually curated corpora of PubMed abstracts and annotated sentences to evaluate the efficacy of literature mining on two tasks: first, identifying PubMed abstracts containing pharmacokinetic evidence of DDIs; second, extracting sentences containing such evidence from abstracts. We implemented a text mining pipeline and evaluated it using several linear classifiers and a variety of feature transforms. The most important textual features in the abstract and sentence classification tasks were analyzed. We also investigated the performance benefits of using features derived from PubMed metadata fields, various publicly available named entity recognizers, and pharmacokinetic dictionaries. Several classifiers performed very well in distinguishing relevant and irrelevant abstracts (reaching F1≈0.93, MCC≈0.74, iAUC≈0.99) and sentences (F1≈0.76, MCC≈0.65, iAUC≈0.83). We found that word bigram features were important for achieving optimal classifier performance and that features derived from Medical Subject Headings (MeSH) terms significantly improved abstract classification. We also found that some drug-related named entity recognition tools and dictionaries led to slight but significant improvements, especially in classification of evidence sentences. Based on our thorough analysis of classifiers and feature transforms and the high classification performance achieved, we demonstrate that literature mining can aid DDI discovery by supporting automatic extraction of specific types of experimental evidence. PMID:25961290

Experimental invalidation of phase-transition-induced elastic softening in CrN

NASA Astrophysics Data System (ADS)

Wang, Shanmin; Yu, Xiaohui; Zhang, Jianzhong; Chen, Miao; Zhu, Jinlong; Wang, Liping; He, Duanwei; Lin, Zhijun; Zhang, Ruifeng; Leinenweber, Kurt; Zhao, Yusheng

2012-08-01

We report experimental results of phase stability and incompressibility of CrN. The obtained bulk moduli for cubic and orthorhombic CrN are 257 and 262 GPa, respectively. These results invalidate the conclusion of phase-transition-induced elastic softening recently reported based on nonmagnetic simulations for cubic CrN [Nature Mater.NMAACR1476-112210.1038/nmat2549 8, 947 (2009)]. On the other hand, they provide the only experimental evidence to support the computational models involving the local magnetic moment of Cr atoms [Nature Mater.NMAACR1476-112210.1038/nmat2722 9, 283 (2010)], indicating that atomic spin has a profound influence on the material's elastic properties. We also demonstrate that nonstoichiometry in CrNx has strong effects on its structural stability.

Will smaller plates lead to smaller waists? A systematic review and meta-analysis of the effect that experimental manipulation of dishware size has on energy consumption.

PubMed

Robinson, E; Nolan, S; Tudur-Smith, C; Boyland, E J; Harrold, J A; Hardman, C A; Halford, J C G

2014-10-01

It has been suggested that providing consumers with smaller dishware may prove an effective way of helping people eat less and preventing weight gain, but experimental evidence supporting this has been mixed. The objective of the present work was to examine the current evidence base for whether experimentally manipulated differences in dishware size influence food consumption. We systematically reviewed studies that experimentally manipulated the dishware size participants served themselves at a meal with and measured subsequent food intake. We used inverse variance meta-analysis, calculating the standardized mean difference (SMD) in food intake between smaller and larger dishware size conditions. Nine experiments from eight publications were eligible for inclusion. The majority of experiments found no significance difference in food intake when participants ate from smaller vs. larger dishware. With all available data included, analysis indicated a marginal effect of dishware size on food intake, with larger dishware size associated with greater intake. However, this effect was small and there was a large amount of heterogeneity across studies (SMD: -0.18, 95% confidence interval: -0.35, 0.00, I(2) = 77%). Evidence to date does not show that dishware size has a consistent effect on food intake, so recommendations surrounding the use of smaller plates/dishware to improve public health may be premature. © 2014 The Authors. obesity reviews © 2014 World Obesity.

Community interventions providing care and support to orphans and vulnerable children: a review of evaluation evidence.

PubMed

Schenk, Katie D

2009-07-01

Children affected by HIV in their families and communities face multiple risks to their health, education and psychosocial wellbeing. Community interventions for children who have been orphaned or rendered vulnerable take many forms, including educational assistance, home-based care, legal protection and psychosocial support. Despite a recent influx of funding for programme implementation, there exists little evidence to inform policymakers about whether their investments are improving the lives of vulnerable children and meeting key benchmarks including the Millennium Development Goals. This paper reviews the current evidence base on evaluations of community interventions for orphans and vulnerable children (OVC) in high HIV-prevalence African settings, focusing on studies' methodologies. Sources reviewed include published research studies and evidence from the unpublished programmatic "grey literature" located through database and internet searches. A total of 21 studies, varying in scope and generalisability, were identified. Interventions reviewed address children's wellbeing through various strategies within their communities. Evaluation methodologies reflect quantitative and qualitative approaches, including surveys (with and without baseline or comparison data), costing studies, focus groups, interviews, case studies, and participatory review techniques. Varied study methodologies reflect diverse research questions, various intervention types, and the challenges associated with evaluating complex interventions; highlighting the need to broaden the research paradigm in order to build the evidence base by including quasi-experimental and process evaluation approaches, and seeking further insights through participatory qualitative methodologies and costing studies. Although findings overall indicate the value of community interventions in effecting measurable improvements in child and family wellbeing, the quality and rigour of evidence is varied. A strategic research agenda is urgently needed to inform resource allocation and programme management decisions. Immediate imperatives include building local technical capacity to conduct quantitative and qualitative evaluation research, and strengthening monitoring and evaluation systems to collect process and outcome data (including costing) on key support models. Donors and implementers must support the collection of sound empirical evidence to inform the development and scale-up of OVC programmes.

Experimental Observation of Bulk Liquid Water Structure in ``No Man's Land''

NASA Astrophysics Data System (ADS)

Sellberg, Jonas; McQueen, Trevor; Huang, Congcong; Loh, Duane; Laksmono, Hartawan; Sierra, Raymond; Hampton, Christina; Starodub, Dmitri; Deponte, Daniel; Martin, Andrew; Barty, Anton; Wikfeldt, Thor; Schlesinger, Daniel; Pettersson, Lars; Beye, Martin; Nordlund, Dennis; Weiss, Thomas; Feldkamp, Jan; Caronna, Chiara; Seibert, Marvin; Messerschmidt, Marc; Williams, Garth; Boutet, Sebastien; Bogan, Michael; Nilsson, Anders

2013-03-01

Experiments on pure bulk water below about 235 K have so far been difficult: water crystallization occurs very rapidly below the homogeneous nucleation temperature of 232 K and above 160 K, leading to a ``no man's land'' devoid of experimental results regarding the structure. Here, we demonstrate a new, general experimental approach to study the structure of liquid states at supercooled conditions below their limit of homogeneous nucleation. We use femtosecond x-ray pulses generated by the LCLS x-ray laser to probe evaporatively cooled droplets of supercooled bulk water and find experimental evidence for the existence of metastable bulk liquid water down to temperatures of 223 K in the previously largely unexplored ``no man's land''. We acknoweledge NSF (CHE-0809324), Office of Basic Energy Sciences, and the Swedish Research Council for financial support.

Effects Of The ACA's Health Insurance Marketplaces On The Previously Uninsured: A Quasi-Experimental Analysis.

PubMed

Goldman, Anna L; McCormick, Danny; Haas, Jennifer S; Sommers, Benjamin D

2018-04-01

Descriptive studies have suggested that the Affordable Care Act's (ACA's) health insurance Marketplaces improved access to care. However, no evidence from quasi-experimental studies is available to support these findings. We used longitudinal survey data to compare previously uninsured adults with incomes that made them eligible for subsidized Marketplace coverage (138-400 percent of the federal poverty level) to those who had employer-sponsored insurance before the ACA with incomes in the same range. Among the previously uninsured group, the ACA led to a significant decline in the uninsurance rate, decreased barriers to medical care, increased the use of outpatient services and prescription drugs, and increased diagnoses of hypertension, compared to a control group with stable employer-sponsored insurance. Changes were largest among previously uninsured people with incomes of 138-250 percent of poverty, who were eligible for the ACA's cost-sharing reductions. Our quasi-experimental approach provides rigorous new evidence that the ACA's Marketplaces led to improvements in several important health care outcomes, particularly among low-income adults.

Physical realization of the Glauber quantum oscillator.

PubMed

Gentilini, Silvia; Braidotti, Maria Chiara; Marcucci, Giulia; DelRe, Eugenio; Conti, Claudio

2015-11-02

More than thirty years ago Glauber suggested that the link between the reversible microscopic and the irreversible macroscopic world can be formulated in physical terms through an inverted harmonic oscillator describing quantum amplifiers. Further theoretical studies have shown that the paradigm for irreversibility is indeed the reversed harmonic oscillator. As outlined by Glauber, providing experimental evidence of these idealized physical systems could open the way to a variety of fundamental studies, for example to simulate irreversible quantum dynamics and explain the arrow of time. However, supporting experimental evidence of reversed quantized oscillators is lacking. We report the direct observation of exploding n = 0 and n = 2 discrete states and Γ0 and Γ2 quantized decay rates of a reversed harmonic oscillator generated by an optical photothermal nonlinearity. Our results give experimental validation to the main prediction of irreversible quantum mechanics, that is, the existence of states with quantized decay rates. Our results also provide a novel perspective to optical shock-waves, potentially useful for applications as lasers, optical amplifiers, white-light and X-ray generation.

The impact of embedded support for underprepared students in a college chemistry course

NASA Astrophysics Data System (ADS)

Hesser, Tiffany L.

This quasi-experimental study examined the impact of embedded support on academic success for students requiring remediation in college chemistry. Additional support for underprepared students incorporated within a course is recommended by Connecticut's Public Act 12-40, An Act Concerning College Readiness and Completion. For this study, embedded support consisted of weekly instructional support sessions and introduced the concepts of metacognitive awareness and motivation in learning. Students' progression through the course was measured using a series of standardized questions. Metacognitive awareness and motivation levels were measure at the start and completion of the semester using the Metacognitive Awareness Inventory (MAI) and Motivated Student Learning Questionnaire (MSLQ). It was found that with embedded support, underprepared students performed academically at a level equivalent to that of their college-ready peers. Based on these results, this embedded support model as an evidence-based practice should be considered in class development or policies surrounding students identified as underprepared.

How Can Children with Mild Literacy Difficulties Be Supported at the Transition to Secondary School? A Small-Scale Quasi-Experimental Study

ERIC Educational Resources Information Center

Bark, Caroline; Brooks, Greg

2016-01-01

There is evidence that pupils with weak literacy skills struggle on transition to secondary school. Many experience a drop in attainment in the summer break between the two. A British government-funded programme of rigorously designed research on boosting literacy at transition had (by 2015) found only four of 15 interventions evaluated had…

Influence of Limitedly Visible Leafy Indoor Plants on the Psychology, Behavior, and Health of Students at a Junior High School in Taiwan

ERIC Educational Resources Information Center

Han, Ke-Tsung

2009-01-01

There is growing evidence to support the notion that contact with nature is helpful for emotional states, attention, mental fatigue, behavior, and personal health. This study adopts a quasi-experimental approach to investigate the effects of limitedly visible indoor plants on students' psychology, physiology, and behavior and uses a control-series…

Serum markers of bone turnover change in response to depletion and repletion of fruit and vegetable intake in adults: A 28-wk single-arm experimental feeding intervention

USDA-ARS?s Scientific Manuscript database

Data from controlled intervention trials are lacking to support observational evidence suggesting a positive association between intake of fruit and vegetable (FV) and bone health. The objective of this study was to assess serum markers of bone turnover change in response to FV depletion and repleti...

Recombinant PrPSc shares structural features with brain-derived PrPSc suggesting that they have a similar architecture: Insights from limited proteolysis

USDA-ARS?s Scientific Manuscript database

An extensive body of experimental and spectroscopic evidence supports the hypothesis that PrPSc is a multimer of 4-rung ß-solenoids, and that individual PrPSc solenoids stack to form amyloid fibers. We recently used limited proteolysis to map the ß-strands and connecting loops that make up the PrPSc...

Using Encoding Instruction to Improve the Reading and Spelling Performances of Elementary Students at Risk for Literacy Difficulties: A Best-Evidence Synthesis

ERIC Educational Resources Information Center

Weiser, Beverly; Mathes, Patricia

2011-01-01

Although connectionist models provide a framework explaining how the decoding and encoding abilities work reciprocally to enhance reading and spelling ability, encoding instruction in today's schools is not a priority. Although a limited amount of high-quality experimental or control studies to date (N = 11) give empirical support to using direct,…

The restorative logic of punishment: another argument in favor of weak selection.

PubMed

Baumard, Nicolas

2012-02-01

Strong reciprocity theorists claim that punishment has evolved to promote the good of the group and to deter cheating. By contrast, weak reciprocity suggests that punishment aims to restore justice (i.e., reciprocity) between the criminal and his victim. Experimental evidences as well as field observations suggest that humans punish criminals to restore fairness rather than to support group cooperation.

Incretin-Based Therapies for Diabetic Complications: Basic Mechanisms and Clinical Evidence

PubMed Central

Kawanami, Daiji; Matoba, Keiichiro; Sango, Kazunori; Utsunomiya, Kazunori

2016-01-01

An increase in the rates of morbidity and mortality associated with diabetic complications is a global concern. Glycemic control is important to prevent the development and progression of diabetic complications. Various classes of anti-diabetic agents are currently available, and their pleiotropic effects on diabetic complications have been investigated. Incretin-based therapies such as dipeptidyl peptidase (DPP)-4 inhibitors and glucagon-like peptide-1 receptor agonists (GLP-1RA) are now widely used in the treatment of patients with type 2 diabetes. A series of experimental studies showed that incretin-based therapies have beneficial effects on diabetic complications, independent of their glucose-lowering abilities, which are mediated by anti-inflammatory and anti-oxidative stress properties. Based on these findings, clinical studies to assess the effects of DPP-4 inhibitors and GLP-1RA on diabetic microvascular and macrovascular complications have been performed. Several but not all studies have provided evidence to support the beneficial effects of incretin-based therapies on diabetic complications in patients with type 2 diabetes. We herein discuss the experimental and clinical evidence of incretin-based therapy for diabetic complications. PMID:27483245

The CRISP theory of hippocampal function in episodic memory

PubMed Central

Cheng, Sen

2013-01-01

Over the past four decades, a “standard framework” has emerged to explain the neural mechanisms of episodic memory storage. This framework has been instrumental in driving hippocampal research forward and now dominates the design and interpretation of experimental and theoretical studies. It postulates that cortical inputs drive plasticity in the recurrent cornu ammonis 3 (CA3) synapses to rapidly imprint memories as attractor states in CA3. Here we review a range of experimental studies and argue that the evidence against the standard framework is mounting, notwithstanding the considerable evidence in its support. We propose CRISP as an alternative theory to the standard framework. CRISP is based on Context Reset by dentate gyrus (DG), Intrinsic Sequences in CA3, and Pattern completion in cornu ammonis 1 (CA1). Compared to previous models, CRISP uses a radically different mechanism for storing episodic memories in the hippocampus. Neural sequences are intrinsic to CA3, and inputs are mapped onto these intrinsic sequences through synaptic plasticity in the feedforward projections of the hippocampus. Hence, CRISP does not require plasticity in the recurrent CA3 synapses during the storage process. Like in other theories DG and CA1 play supporting roles, however, their function in CRISP have distinct implications. For instance, CA1 performs pattern completion in the absence of CA3 and DG contributes to episodic memory retrieval, increasing the speed, precision, and robustness of retrieval. We propose the conceptual theory, discuss its implications for experimental results and suggest testable predictions. It appears that CRISP not only accounts for those experimental results that are consistent with the standard framework, but also for results that are at odds with the standard framework. We therefore suggest that CRISP is a viable, and perhaps superior, theory for the hippocampal function in episodic memory. PMID:23653597

Human Health Effects of Biphenyl: Key Findings and Scientific Issues.

PubMed

Li, Zheng; Hogan, Karen A; Cai, Christine; Rieth, Susan

2016-06-01

In support of the Integrated Risk Information System (IRIS), the U.S. Environmental Protection Agency (EPA) has evaluated the human health hazards of biphenyl exposure. We review key findings and scientific issues regarding expected human health effects of biphenyl. Scientific literature from 1926 through September 2012 was critically evaluated to identify potential human health hazards associated with biphenyl exposure. Key issues related to the carcinogenicity and noncancer health hazards of biphenyl were examined based on evidence from experimental animal bioassays and mechanistic studies. Systematic consideration of experimental animal studies of oral biphenyl exposure took into account the variety of study designs (e.g., study sizes, exposure levels, and exposure durations) to reconcile differing reported results. The available mechanistic and toxicokinetic evidence supports the hypothesis that male rat urinary bladder tumors arise through urinary bladder calculi formation but is insufficient to hypothesize a mode of action for liver tumors in female mice. Biphenyl and its metabolites may induce genetic damage, but a role for genotoxicity in biphenyl-induced carcinogenicity has not been established. The available health effects data for biphenyl provides suggestive evidence for carcinogenicity in humans, based on increased incidences of male rat urinary bladder tumors at high exposure levels and on female mouse liver tumors. Kidney toxicity is also a potential human health hazard of biphenyl exposure. Li Z, Hogan KA, Cai C, Rieth S. 2016. Human health effects of biphenyl: key findings and scientific issues. Environ Health Perspect 124:703-712; http://dx.doi.org/10.1289/ehp.1509730.

Cancer prevention by green tea: evidence from epidemiologic studies.

PubMed

Yuan, Jian-Min

2013-12-01

In contrast to the consistent results of an inhibitory effect of green tea extracts and tea polyphenols on the development and growth of carcinogen-induced tumors in experimental animal models, results from human studies are mixed. Both observational and intervention studies have provided evidence in support of a protective role of green tea intake in the development of oral-digestive tract cancer or an inhibitory role of oral supplementation of green tea extract on a precancerous lesion of oral cavity. Evidence in support of green tea intake against the development of liver cancer risk is limited and inconsistent. An inverse association between green tea intake and lung cancer risk has been observed among never smokers but not among smokers. Although observational studies do not support a beneficial role of tea intake against the development of prostate cancer, several phase 2 clinical trials have shown an inhibitory effect of green tea extract against the progression of prostate premalignant lesions to malignant tumors. Prospective epidemiologic studies so far have not provided evidence for a protective effect of green tea consumption on breast cancer development. Current data neither confirm nor refute a definitive cancer-preventive role of green tea intake. Large randomized intervention trials on the efficacy of green tea polyphenols or extracts are required before a recommendation for green tea consumption for cancer prevention should be made.

Pro-sexual and androgen enhancing effects of Tribulus terrestris L.: Fact or Fiction.

PubMed

Neychev, Vladimir; Mitev, Vanyo

2016-02-17

Historically, aphrodisiacs have had a reputation for making sex more achievable and satisfying. It has been long believed that Tribulus terrestris L. (TT), an annual plant of the family Zygophyllaceae, possesses aphrodisiac properties purportedly attributed to its ability to influence levels or mimic function of sex hormones. Due to this appealing beliefs, the popularity of medicinal products from TT is expanding at a remarkable pace among consumers who are attempting to enhance their sexual health. However, reliable scientific evidence supporting these purported bioactivities are scant and far from conclusive. To critically analyze and updated the evidence supporting a role for TT as an aphrodisiac and to reappraise the widely believed view of TT as an androgen enhancing botanical supplement. An extensive review of the literature was carried out based on systematic search of major scientific databases (PubMed, Elsevier, Springer Link, Google Scholar, Medline Plus, and Web of Science) for studies of phytochemical, pharmacological and traditional uses of TT published between 1968 and 2015. In addition, the reference lists of the available articles were reviewed and relevant studies including material in journals which are not indexed internationally were reviewed. Analysis of phytochemical and pharmacological studies in humans and animals revealed an important role for TT in treating erectile dysfunction and sexual desire problems; however, empirical evidence to support the hypothesis that this desirable effects are due to androgen enhancing properties of TT is, at best, inconclusive, and analysis of empirical evidence from a comprehensive review of available literature proved this hypothesis wrong. While the mechanisms underlying TT aphrodisiac activity remain largely unknown, there is emerging compelling evidence from experimental studies in animals for possible endothelium and nitric oxide-dependent mechanisms underlying TT aphrodisiac and pro-erectile activities. It is becoming increasingly clear that the deep-seated traditional view of TT bioactivity focused exclusively on its androgen enhancing properties is outdated and incapable for accommodating the emerging evidence from recent clinical and experimental studies pointing toward new and, perhaps, more plausible modes of action. Novel paradigms guiding the development of new testable hypotheses for TT aphrodisiac properties are needed to stimulate further investigations into potential biological mechanisms in which many apparently conflicting observations can be reconciled. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

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

Farzan, Shohreh F.; Karagas, Margaret R.; Section of Biostatistics and Epidemiology, Department of Community and Family Medicine and Norris Cotton Cancer Center, Geisel School of Medicine at Dartmouth, Lebanon, NH 03756

Background: There is a growing body of evidence that prenatal and early childhood exposure to arsenic from drinking water can have serious long-term health implications. Objectives: Our goal was to understand the potential long-term health and disease risks associated with in utero and early life exposure to arsenic, as well as to examine parallels between findings from epidemiological studies with those from experimental animal models. Methods: We examined the current literature and identified relevant studies through PubMed by using combinations of the search terms “arsenic”, “in utero”, “transplacental”, “prenatal” and “fetal”. Discussion: Ecological studies have indicated associations between in uteromore » and/or early life exposure to arsenic at high levels and increases in mortality from cancer, cardiovascular disease and respiratory disease. Additional data from epidemiologic studies suggest intermediate effects in early life that are related to risk of these and other outcomes in adulthood. Experimental animal studies largely support studies in humans, with strong evidence of transplacental carcinogenesis, atherosclerosis and respiratory disease, as well as insight into potential underlying mechanisms of arsenic's health effects. Conclusions: As millions worldwide are exposed to arsenic and evidence continues to support a role for in utero arsenic exposure in the development of a range of later life diseases, there is a need for more prospective studies examining arsenic's relation to early indicators of disease and at lower exposure levels. - Highlights: • We review in utero and early-life As exposure impacts on lifelong disease risks. • Evidence indicates that early-life As increases risks of lung disease, cancer and CVD. • Animal work largely parallels human studies and may lead to new research directions. • Prospective studies and individual exposure assessments with biomarkers are needed. • Assessing intermediary endpoints may aid early intervention and establish causality.« less

Cancer immunotherapy by immunosuppression

PubMed Central

2010-01-01

We have previously suggested that the stimulatory effect of a weak immune reaction on tumor growth may be necessary for the growth of incipient tumors. In the present paper, we enlarge upon and extend that idea by collecting evidence in the literature bearing upon this new hypothesis that a growing cancer, whether in man or mouse, is throughout its lifespan, probably growing and progressing because of continued immune stimulation by a weak immune reaction. We also suggest that prolonged immunosuppression might interfere with progression and thus be an aid to therapy. While most of the considerable evidence that supports the hypothesis comes from observations of experimental mouse tumors, there is suggestive evidence that human tumors may behave in much the same way, and as far as we can ascertain, there is no present evidence that necessarily refutes the hypothesis. PMID:21159199

The antiquity of empathy.

PubMed

de Waal, Frans B M

2012-05-18

The view of humans as violent war-prone apes is poorly supported by archaeological evidence and only partly supported by the behavior of our closest primate relatives, chimpanzees and bonobos. Whereas the first species is marked by xenophobia, the second is relatively peaceful and highly empathic in both behavior and brain organization. Animal empathy is best regarded as a multilayered phenomenon, built around motor mirroring and shared neural representations at basal levels, that develops into more advanced cognitive perspective-taking in large-brained species. As indicated by both observational and experimental studies on our closest relatives, empathy may be the main motivator of prosocial behavior.

False memories for dissonance inducing events.

PubMed

Rodriguez, Dario N; Strange, Deryn

2015-01-01

Memories serve as a "database" of the self and people often produce distorted memories that support their self-concepts. One, surprisingly untested, possibility is that cognitive dissonance may be one mechanism by which people may misremember their past. We tested this hypothesis using an induced-compliance paradigm: participants either chose or were forced to write a counterattitudinal essay supporting a tuition increase and were afforded the opportunity to reduce dissonance via attitude shift or denial of responsibility. They then reported their memories for the experimental instructions and their initial attitudes (assessed two days prior to the laboratory session). Participants who chose to write the essay exhibited the predicted attitude-shift effect, and were more likely to misremember their initial attitudes and the experimental instruction than those who were forced to write the essay. Overall, our results provide evidence that cognitive dissonance may yield memory distortion, filling a significant gap in the motivated cognition and memory literatures.

Spectroscopic Observation of a Hydrogenated CO Dimer Intermediate During CO Reduction on Cu(100) Electrodes.

PubMed

Pérez-Gallent, Elena; Figueiredo, Marta C; Calle-Vallejo, Federico; Koper, Marc T M

2017-03-20

Carbon dioxide and carbon monoxide can be electrochemically reduced to useful products such as ethylene and ethanol on copper electrocatalysts. The process is yet to be optimized and the exact mechanism and the corresponding reaction intermediates are under debate or unknown. In particular, it has been hypothesized that the C-C bond formation proceeds via CO dimerization and further hydrogenation. Although computational support for this hypothesis exists, direct experimental evidence has been elusive. In this work, we detect a hydrogenated dimer intermediate (OCCOH) using Fourier transform infrared spectroscopy at low overpotentials in LiOH solutions. Density functional theory calculations support our assignment of the observed vibrational bands. The formation of this intermediate is structure sensitive, as it is observed only during CO reduction on Cu(100) and not on Cu(111), in agreement with previous experimental and computational observations. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

Maze-solving by chemotaxis

NASA Astrophysics Data System (ADS)

Reynolds, A. M.

2010-06-01

Here, we report on numerical simulations showing that chemotaxis will take a body through a maze via the shortest possible route to the source of a chemoattractant. This is a robust finding that does not depend on the geometrical makeup of the maze. The predictions are supported by recent experimental studies which have shown that by moving down gradients in pH , a droplet of organic solvent can find the shortest of multiple possible paths through a maze to an acid-soaked exit. They are also consistent with numerical and experimental evidence that plant-parasitic nematodes take the shortest route through the labyrinth of air-filled pores within soil to preferred host plants that produce volatile chemoattractants. The predictions support the view that maze-solving is a robust property of chemotaxis and is not specific to particular kinds of maze or to the fractal structure of air-filled channels within soils.

The effect of nature of science metacognitive prompts on science students' content and nature of science knowledge, metacognition, and self-regulatory efficacy

NASA Astrophysics Data System (ADS)

Peters, Erin E.

The purpose of the present quasi-experimental mixed-method design is to examine the effectiveness of a developmental intervention (4-phase EMPNOS) to teach the nature of science using metacognitive prompts embedded in an inquiry unit. Eighty-eight (N=88) eighth grade students from four classrooms were randomly assigned to an experimental and a control group. All participants were asked to respond to a number of tests (content and nature of science knowledge) and surveys (metacognition of the nature of science, metacognitive orientation of the classroom, and self-regulatory efficacy). Participants were also interviewed to find problem solving techniques and shared experiences between the groups. It was hypothesized that the experimental group would outperform the control group in all measures. Partial support for the hypotheses was found. Specifically, results showed significant gains in content knowledge and nature of science knowledge of the experimental group over the control group. Qualitative findings revealed that students in the control group reported valuing authority over evidence, while the experimental group reported that they depended on consensus of their group on the interpretation of the evidence rather than authority, which is more closely aligned to the aspects of the nature of science. Four-phase EMPNOS may have implications as a useful classroom tool in guiding students to check their thinking for alignment to scientific thinking.

The origin of light hydrocarbons

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

Mango, F.D.

2000-04-01

The light hydrocarbons (LHs) are probably intermediates in the catalytic decomposition of oil to gas. Two lines of evidence support this possibility. First, the reaction was duplicated experimentally under moderate conditions. Second, natural LHs exhibit the characteristics of catalytic products, in particular a proportionality between isomers: (xy{sub i})/(x{sub i}y) = {alpha} (where x and x{sub i} are isomers; y and y{sub i} are isomers that are structurally similar to x and x{sub i}; and {alpha} is a constant). All oils exhibit this relationship with coefficients of correlation reaching 0.99. Isomer ratios change systematically with concentrations, some approaching thermodynamic equilibrium, othersmore » not. The correlations reported are the strongest yet disclosed for the LHs. Isomers are related in triads (e.g., n-hexane {leftrightarrow} 2-methylpentane {leftrightarrow} 3-methylpentane), consistent with cyclopropane precursors. The LHs obtained experimentally are indistinguishable from natural LHs in (xy{sub i})/(x{sub i}y). These relationships are not explained by physical fractionations, equilibrium control, or noncatalytic modes of origin. A catalytic origin, on the other hand, has precedence, economy and experimental support.« less

Evidence-based nursing: a stereotyped view of quantitative and experimental research could work against professional autonomy and authority.

PubMed

Bonell, C

1999-07-01

In recent years, there have been calls within the United Kingdom's National Health Service (NHS) for evidence-based health care. These resonate with long-standing calls for nursing to become a research-based profession. Evidence-based practice could enable nurses to demonstrate their unique contribution to health care outcomes, and support their seeking greater professionalization, in terms of enhanced authority and autonomy. Nursing's professionalization project, and, within this, various practices comprising the 'new nursing', whilst sometimes not delivering all that was hoped of them, have been important in developing certain conditions conducive to developing evidence-based practice, notably a critical perspective on practice and a reluctance merely to follow physicians' orders. However, nursing has often been hesitant in its adoption of quantitative and experimental research. This hesitancy, it is argued, has been influenced by the propounding by some authors within the new nursing of a stereotyped view of quantitative/experimental methods which equates them with a number of methodological and philosophical points which are deemed, by at least some of these authors, as inimical to, or problematic within, nursing research. It is argued that, not only is the logic on which the various stereotyped views are based flawed, but further, that the wider influence of these viewpoints on nurses could lead to a greater marginalization of nurses in research and evidence-based practice initiatives, thus perhaps leading to evidence-based nursing being led by other groups. In the longer term, this might result in a form of evidence-based nursing emphasizing routinization, thus--ironically--working against strategies of professional authority and autonomy embedded in the new nursing. Nursing research should instead follow the example of nurse researchers who already embrace multiple methods. While the paper describes United Kingdom experiences and debates, points raised about the importance of questioning stereotyped views of research should have international relevance.

Potential damage to DC superconducting magnets due to the high frequency electromagnetic waves

NASA Technical Reports Server (NTRS)

Gabriel, G. J.

1977-01-01

Experimental data are presented in support of the hypothesis that a dc superconducting magnet coil does not behave strictly as an inductor, but as a complicated electrodynamic device capable of supporting electromagnetic waves. Travel times of nanosecond pulses and evidence of sinusoidal standing waves were observed on a prototype four-layer solenoidal coil at room temperature. Ringing observed during switching transients appears as a sequence of multiple reflected square pulses whose durations are related to the layer lengths. With sinusoidal excitation of the coil, the voltage amplitude between a pair of points on the coil exhibits maxima at those frequencies such that the distance between these points is an odd multiple of half wavelength in free space. Evidence indicates that any disturbance, such as that resulting from switching or sudden fault, initiates multiple reflections between layers, thus raising the possibility for sufficiently high voltages to cause breakdown.

Does Current Scientific Evidence Support a Link Between Light at Night and Breast Cancer Among Female Night-Shift Nurses?

PubMed Central

Dickerman, Barbra; Liu, Jianghong

2014-01-01

Breast cancer is increasingly prevalent in industrialized regions of the world, and exposure to light at night (LAN) has been proposed as a potential risk factor. Epidemiological observations have documented an increased breast cancer risk among female night-shift workers, and strong experimental evidence for this relationship has also been found in rodent models. Indirect support for the LAN hypothesis comes from studies involving blind women, sleep duration, bedroom light levels, and community nighttime light levels. This article reviews the literature, discusses possible mechanisms of action, and provides recommendations for occupational health nursing research, practice, and education. Research is needed to further explore the relationship between exposure to LAN and breast cancer risk and elucidate the mechanisms underlying this relationship before interventions can be designed for prevention and mitigation of breast cancer. PMID:22658734

The protective function of noncoding DNA in genome defense of eukaryotic male germ cells.

PubMed

Qiu, Guo-Hua; Huang, Cuiqin; Zheng, Xintian; Yang, Xiaoyan

2018-04-01

Peripheral and abundant noncoding DNA has been hypothesized to protect the genome and the central protein-coding sequences against DNA damage in somatic genome. In the cytosol, invading exogenous nucleic acids may first be deactivated by small RNAs encoded by noncoding DNA via mechanisms similar to the prokaryotic CRISPR-Cas system. In the nucleus, the radicals generated by radiation in the cytosol, radiation energy and invading exogenous nucleic acids are absorbed, blocked and/or reduced by peripheral heterochromatin, and damaged DNA in heterochromatin is removed and excluded from the nucleus to the cytoplasm through nuclear pore complexes. To further strengthen the hypothesis, this review summarizes the experimental evidence supporting the protective function of noncoding DNA in the genome of male germ cells. Based on these data, this review provides evidence supporting the protective role of noncoding DNA in the genome defense of sperm genome through similar mechanisms to those of the somatic genome.

Barrett oesophagus: lessons on its origins from the lesion itself.

PubMed

McDonald, Stuart A C; Lavery, Danielle; Wright, Nicholas A; Jansen, Marnix

2015-01-01

Barrett oesophagus develops when the lower oesophageal squamous epithelium is replaced with columnar epithelium, which shows both intestinal and gastric differentiation. No consensus has been reached on the origin of Barrett oesophagus. Theories include a direct origin from the oesophageal-stratified squamous epithelium, or by proximal migration of the gastric cardiac epithelium with subsequent intestinalization. Variations of this theory suggest the origin is a distinctive cell at the squamocolumnar junction, the oesophageal gland ducts, or circulating bone-marrow-derived cells. Much of the supporting evidence comes from experimental models and not from studies of Barrett mucosa. In this Perspectives article, we look at the Barrett lesion itself: at its phenotype, its complexity, its clonal architecture and its stem cell organization. We conclude that Barrett glands are unique structures, but share many similarities with gastric glands undergoing the process of intestinal metaplasia. We conclude that current evidence most strongly supports an origin from stem cells in the cardia.

Metagenomic identification of active methanogens and methanotrophs in serpentinite springs of the Voltri Massif, Italy.

PubMed

Brazelton, William J; Thornton, Christopher N; Hyer, Alex; Twing, Katrina I; Longino, August A; Lang, Susan Q; Lilley, Marvin D; Früh-Green, Gretchen L; Schrenk, Matthew O

2017-01-01

The production of hydrogen and methane by geochemical reactions associated with the serpentinization of ultramafic rocks can potentially support subsurface microbial ecosystems independent of the photosynthetic biosphere. Methanogenic and methanotrophic microorganisms are abundant in marine hydrothermal systems heavily influenced by serpentinization, but evidence for methane-cycling archaea and bacteria in continental serpentinite springs has been limited. This report provides metagenomic and experimental evidence for active methanogenesis and methanotrophy by microbial communities in serpentinite springs of the Voltri Massif, Italy. Methanogens belonging to family Methanobacteriaceae and methanotrophic bacteria belonging to family Methylococcaceae were heavily enriched in three ultrabasic springs (pH 12). Metagenomic data also suggest the potential for hydrogen oxidation, hydrogen production, carbon fixation, fermentation, and organic acid metabolism in the ultrabasic springs. The predicted metabolic capabilities are consistent with an active subsurface ecosystem supported by energy and carbon liberated by geochemical reactions within the serpentinite rocks of the Voltri Massif.

The Alkaline Hydrolysis of Sulfonate Esters: Challenges in Interpreting Experimental and Theoretical Data

PubMed Central

2013-01-01

Sulfonate ester hydrolysis has been the subject of recent debate, with experimental evidence interpreted in terms of both stepwise and concerted mechanisms. In particular, a recent study of the alkaline hydrolysis of a series of benzene arylsulfonates (Babtie et al., Org. Biomol. Chem.10, 2012, 8095) presented a nonlinear Brønsted plot, which was explained in terms of a change from a stepwise mechanism involving a pentavalent intermediate for poorer leaving groups to a fully concerted mechanism for good leaving groups and supported by a theoretical study. In the present work, we have performed a detailed computational study of the hydrolysis of these compounds and find no computational evidence for a thermodynamically stable intermediate for any of these compounds. Additionally, we have extended the experimental data to include pyridine-3-yl benzene sulfonate and its N-oxide and N-methylpyridinium derivatives. Inclusion of these compounds converts the Brønsted plot to a moderately scattered but linear correlation and gives a very good Hammett correlation. These data suggest a concerted pathway for this reaction that proceeds via an early transition state with little bond cleavage to the leaving group, highlighting the care that needs to be taken with the interpretation of experimental and especially theoretical data. PMID:24279349

Recommendations for the U.S. Coast Guard Survival Prediction Tool

DTIC Science & Technology

2009-04-01

model. Not enough data to support modeling of how alcohol impairs swimming ability. Experimental evidence shows no significant cooling effect 50...equation. When matched for physical attributes, females cool more quickly than males due to lower metabolic response and greater surface-area-to-mass...April 2009 However, the average female has about 10% more body fat than the average male so, on average, males cool faster than females. (Tipton

The Efficacy of ’Don’t Ask, Don’t Tell’

DTIC Science & Technology

2009-01-01

psychologists explored the concepts, experimental and cor- relation evidence supported dividing cohesion into two distinct types: social cohesion and task...cohesion. Social cohesion is the nature and quality of the emotional bonds within a group—the degree to which members spend time together, like...along (that is, has high social cohesion ) would perform better. Almost counterintuitively, it has been shown that in some situations, high social

A Computational Model of Reasoning from the Clinical Literature

PubMed Central

Rennels, Glenn D.

1986-01-01

This paper explores the premise that a formalized representation of empirical studies can play a central role in computer-based decision support. The specific motivations underlying this research include the following propositions: 1. Reasoning from experimental evidence contained in the clinical literature is central to the decisions physicians make in patient care. 2. A computational model, based upon a declarative representation for published reports of clinical studies, can drive a computer program that selectively tailors knowledge of the clinical literature as it is applied to a particular case. 3. The development of such a computational model is an important first step toward filling a void in computer-based decision support systems. Furthermore, the model may help us better understand the general principles of reasoning from experimental evidence both in medicine and other domains. Roundsman is a developmental computer system which draws upon structured representations of the clinical literature in order to critique plans for the management of primary breast cancer. Roundsman is able to produce patient-specific analyses of breast cancer management options based on the 24 clinical studies currently encoded in its knowledge base. The Roundsman system is a first step in exploring how the computer can help to bring a critical analysis of the relevant literature to the physician, structured around a particular patient and treatment decision.

A review of the carcinogenic potential of glyphosate by four independent expert panels and comparison to the IARC assessment.

PubMed

Williams, Gary M; Aardema, Marilyn; Acquavella, John; Berry, Sir Colin; Brusick, David; Burns, Michele M; de Camargo, Joao Lauro Viana; Garabrant, David; Greim, Helmut A; Kier, Larry D; Kirkland, David J; Marsh, Gary; Solomon, Keith R; Sorahan, Tom; Roberts, Ashley; Weed, Douglas L

2016-09-01

The International Agency for Research on Cancer (IARC) published a monograph in 2015 concluding that glyphosate is "probably carcinogenic to humans" (Group 2A) based on limited evidence in humans and sufficient evidence in experimental animals. It was also concluded that there was strong evidence of genotoxicity and oxidative stress. Four Expert Panels have been convened for the purpose of conducting a detailed critique of the evidence in light of IARC's assessment and to review all relevant information pertaining to glyphosate exposure, animal carcinogenicity, genotoxicity, and epidemiologic studies. Two of the Panels (animal bioassay and genetic toxicology) also provided a critique of the IARC position with respect to conclusions made in these areas. The incidences of neoplasms in the animal bioassays were found not to be associated with glyphosate exposure on the basis that they lacked statistical strength, were inconsistent across studies, lacked dose-response relationships, were not associated with preneoplasia, and/or were not plausible from a mechanistic perspective. The overall weight of evidence from the genetic toxicology data supports a conclusion that glyphosate (including GBFs and AMPA) does not pose a genotoxic hazard and therefore, should not be considered support for the classification of glyphosate as a genotoxic carcinogen. The assessment of the epidemiological data found that the data do not support a causal relationship between glyphosate exposure and non-Hodgkin's lymphoma while the data were judged to be too sparse to assess a potential relationship between glyphosate exposure and multiple myeloma. As a result, following the review of the totality of the evidence, the Panels concluded that the data do not support IARC's conclusion that glyphosate is a "probable human carcinogen" and, consistent with previous regulatory assessments, further concluded that glyphosate is unlikely to pose a carcinogenic risk to humans.

Therapist-supported Internet cognitive behavioural therapy for anxiety disorders in adults.

PubMed

Olthuis, Janine V; Watt, Margo C; Bailey, Kristen; Hayden, Jill A; Stewart, Sherry H

2015-03-05

Cognitive behavioural therapy (CBT) is an evidence-based treatment for anxiety disorders. Many people have difficulty accessing treatment, due to a variety of obstacles. Researchers have therefore explored the possibility of using the Internet to deliver CBT; it is important to ensure the decision to promote such treatment is grounded in high quality evidence. To assess the effects of therapist-supported Internet CBT on remission of anxiety disorder diagnosis and reduction of anxiety symptoms in adults as compared to waiting list control, unguided CBT, or face-to-face CBT. Effects of treatment on quality of life and patient satisfaction with the intervention were also assessed. We searched the Cochrane Depression, Anxiety and Neurosis Review Group Specialized Register (CCDANCTR) to 12 April 2013. The CCDANCTR includes relevant randomised controlled trials from EMBASE (1974 -), MEDLINE (1950 -) and PsycINFO (1967 -). We also searched online clinical trial registries and reference lists of included studies. We contacted authors to locate further trials. An update of an initial search (April 2013), conducted in September 2014, identified seven new completed studies, seven previously ongoing studies now completed, and four new ongoing studies. This is a fast-moving area; we plan to update this review shortly, incorporating these new studies. Each identified study was independently assessed for inclusion by two authors. To be included, studies had to be randomised controlled trials of therapist-supported ICBT compared to a waiting list, attention, information, or online discussion group; unguided CBT (that is, self-help); or face-to-face CBT. We included studies that treated adults with an anxiety disorder (panic disorder, agoraphobia, social phobia, post-traumatic stress disorder, acute stress disorder, generalized anxiety disorder, obsessive compulsive disorder, and specific phobia) defined according to the Diagnostic and Statistical Manual of Mental Disorders III, III-R, IV, IV-TR or the International Classification of Disesases 9 or 10. Two authors independently assessed the risk of bias of included studies and judged overall study quality. We used data from intention-to-treat analyses wherever possible. We assessed treatment effect for the dichotomous outcome of clinically important improvement in anxiety using a risk ratio (RR) with 95% confidence interval (CI). For disorder-specific and general anxiety symptom measures and quality of life we assessed continuous scores using standardized mean differences (SMD). We examined statistical heterogeneity using the I(2) statistic. We screened 1000 citations and selected 30 studies (2181 participants) for inclusion. The studies examined social phobia (11 trials), panic disorder with or without agoraphobia (8 trials), generalized anxiety disorder (4 trials), post-traumatic stress disorder (1 trial), and specific phobia (1 trial). Five remaining studies included a range of anxiety disorder diagnoses. Studies were conducted in Sweden (15 trials), Australia (12 trials), Switzerland (2 trials), and the Netherlands (1 trial) and investigated a variety of ICBT protocols. Three primary comparisons were identified, experimental versus waiting list control, experimental versus unguided ICBT, and experimental versus face-to-face CBT.Moderate quality evidence from 9 studies (644 participants) contributed to a pooled RR of 4.18 (95% CI 2.42 to 7.22) for clinically important improvement in anxiety at post-treatment, favouring therapist-supported ICBT over a waiting list, attention, information, or online discussion group only. Similarly, the SMD for disorder-specific symptoms at post-treatment (22 studies, 1573 participants; SMD -1.12, 95% CI -1.39 to -0.85) and general anxiety symptoms at post-treatment (14 studies, 1004 participants; SMD -0.79, 95% CI -1.10 to -0.48) favoured therapist-supported ICBT. The quality of the evidence for both outcomes was low.One study compared unguided CBT to therapist-supported ICBT for clinically important improvement in anxiety at post-treatment, showing no difference in outcome between treatments (54 participants; very low quality evidence). At post-treatment there were no clear differences between unguided CBT and therapist-supported ICBT for disorder-specific anxiety symptoms (4 studies, 253 participants; SMD -0.24, 95% CI -0.69 to 0.21; low quality evidence) or general anxiety symptoms (two studies, 138 participants; SMD 0.28, 95% CI -2.21 to 2.78; low quality evidence).Compared to face-to-face CBT, therapist-supported ICBT showed no significant differences in clinically important improvement in anxiety at post-treatment (4 studies, 365 participants; RR 1.09, 95% CI 0.89 to 1.34; moderate quality evidence). There were also no clear differences between face-to-face and therapist supported ICBT for disorder-specific anxiety symptoms at post-treatment (6 studies, 424 participants; SMD 0.09, 95% CI -0.26 to 0.43; low quality evidence) or general anxiety symptoms at post-treatment (5 studies, 317 participants; SMD 0.17, 95% CI -0.35 to 0.69; low quality evidence).Overall, risk of bias in included studies was low or unclear for most domains. However, due to the nature of psychosocial intervention trials, blinding of participants and personnel, and outcome assessment tended to have a high risk of bias. Heterogeneity across a number of the meta-analyses was substantial, some was explained by type of anxiety disorder or may be meta-analytic measurement artefact due to combining many assessment measures. Adverse events were rarely reported. Therapist-supported ICBT appears to be an efficacious treatment for anxiety in adults. The evidence comparing therapist-supported ICBT to waiting list, attention, information, or online discussion group only control was low to moderate quality, the evidence comparing therapist-supported ICBT to unguided ICBT was low to very low quality, and comparisons of therapist-supported ICBT to face-to-face CBT was low to moderate quality. Further research is needed to better define and measure any potential harms resulting from treatment. These findings suggest that therapist-supported ICBT is more efficacious than a waiting list, attention, information, or online discussion group only control, and that there may not be a significant difference in outcome between unguided CBT and therapist-supported ICBT; however, this latter finding must be interpreted with caution due to imprecision. The evidence suggests that therapist-supported ICBT may not be significantly different from face-to-face CBT in reducing anxiety. Future research should involve equivalence trials comparing ICBT and face-to-face CBT, examine the importance of the role of the therapist in ICBT, and include effectiveness trials of ICBT in real-world settings. A timely update to this review is needed given the fast pace of this area of research.

Molecular cogs of the insect circadian clock.

PubMed

Shirasu, Naoto; Shimohigashi, Yasuyuki; Tominaga, Yoshiya; Shimohigashi, Miki

2003-08-01

During the last five years, enormous progress has been made in understanding the molecular basis of circadian systems, mainly by molecular genetic studies using the mouse and fly. Extensive evidence has revealed that the core clock machinery involves "clock genes" and "clock proteins" functioning as molecular cogs. These participate in transcriptional/translational feedback loops and many homologous clock-components in the fruit fly Drosophila are also expressed in mammalian clock tissues with circadian rhythms. Thus, the mechanisms of the central clock seem to be conserved across animal kingdom. However, some recent studies imply that the present widely accepted molecular models of circadian clocks may not always be supported by the experimental evidence.

Interplay between Oxidative Stress and Nutrient Sensing Signaling in the Developmental Origins of Cardiovascular Disease

PubMed Central

Tain, You-Lin; Hsu, Chien-Ning

2017-01-01

Cardiovascular disease (CVD) presents a global health burden, despite recent advances in management. CVD can originate from early life by so-called “developmental origins of health and disease” (DOHaD). Epidemiological and experimental evidence supports that early-life insults can induce programming of later CVD. Underlying the DOHaD concept, early intervention may offset programming process to prevent the development of CVD, namely reprogramming. Oxidative stress and nutrient sensing signals have been considered to be major mechanisms of cardiovascular programming, while the interplay between these two mechanisms have not been examined in detail. This review summarizes current evidence that supports the link between oxidative stress and nutrient sensing signaling to cardiovascular programming, with an emphasis on the l-arginine–asymmetric dimethylarginine (ADMA)–nitric oxide (NO) pathway. This review provides an overview of evidence from human studies supporting fetal programming of CVD, insight from animal models of cardiovascular programming and oxidative stress, impact of the l-arginine–ADMA–NO pathway in cardiovascular programming, the crosstalk between l-arginine metabolism and nutrient sensing signals, and application of reprogramming interventions to prevent the programming of CVD. A greater understanding of the mechanisms underlying cardiovascular programming is essential to developing early reprogramming interventions to combat the globally growing epidemic of CVD. PMID:28420139

Bupivacaine, levobupivacaine and ropivacaine: are they clinically different?

PubMed

Casati, Andrea; Putzu, Marta

2005-06-01

Two new, long-acting local anaesthetics have been developed after the evidence of bupivacaine-related severe toxicity: levobupivacaine and ropivacaine. Both these agents are pure left-isomers and, based on their three-dimensional structure, they have less toxic potential both on the central nervous system and on the heart. Several clinical studies have evaluated their toxicology and clinical profiles: theoretically and experimentally, some differences can be seen, but the reflections of these characteristics into clinical practice have not been evident. Evaluating randomised, controlled trials that have compared these three local anaesthetics, this chapter supports the evidence that both levobupivacaine and ropivacaine have a clinical profile similar to that of racemic bupivacaine, and that the minimal differences observed between the three agents are mainly related to the slightly different anaesthetic potency, with racemic bupivacaine>levobupivacaine>ropivacaine. However, the reduced toxic potential of the two pure left-isomers supports their use in those clinical situations in which the risk of systemic toxicity related to either overdosing or unwanted intravascular injection is high, such as during epidural or peripheral nerve blocks.

The Brain Basis of Positive and Negative Affect: Evidence from a Meta-Analysis of the Human Neuroimaging Literature

PubMed Central

Lindquist, Kristen A.; Satpute, Ajay B.; Wager, Tor D.; Weber, Jochen; Barrett, Lisa Feldman

2016-01-01

The ability to experience pleasant or unpleasant feelings or to represent objects as “positive” or “negative” is known as representing hedonic “valence.” Although scientists overwhelmingly agree that valence is a basic psychological phenomenon, debate continues about how to best conceptualize it scientifically. We used a meta-analysis of 397 functional magnetic resonance imaging (fMRI) and positron emission tomography studies (containing 914 experimental contrasts and 6827 participants) to test 3 competing hypotheses about the brain basis of valence: the bipolarity hypothesis that positive and negative affect are supported by a brain system that monotonically increases and/or decreases along the valence dimension, the bivalent hypothesis that positive and negative affect are supported by independent brain systems, and the affective workspace hypothesis that positive and negative affect are supported by a flexible set of valence-general regions. We found little evidence for the bipolar or bivalent hypotheses. Findings instead supported the hypothesis that, at the level of brain activity measurable by fMRI, valence is flexibly implemented across instances by a set of valence-general limbic and paralimbic brain regions. PMID:25631056

Effects of a peer support programme for youth social services employees experiencing potentially traumatic events: a protocol for a prospective cohort study

PubMed Central

Guay, Stephane; Tremblay, Nicole; Goncalves, Jane; Bilodeau, Henriette; Geoffrion, Steve

2017-01-01

Introduction The use of peer support programmes to help workers experiencing potentially traumatic events (PTE) has increased in high-risk organisations in the last decades. However, the scientific evidence of its effectiveness is still very limited. This paper aims to describe the protocol of a prospective cohort study that assesses the efficacy of a peer support programme among youth social services employees exposed to a PTE at work on psychological well-being, work functioning and needs of support. Methods and analysis This is a mixed-methods prospective study that will examine workers' evolution four times over a 12-month period in Canada. This study involves: (1) quantitative data obtained through self-administrated questionnaires among 222 workers, and (2) qualitative in-depth interviews with a subsample of 45 workers. This study will compare findings from a cohort who received the support of a peer following a PTE (peer support–experimental protocol) as part of the experimental protocol of the Montreal Youth Social Services-University Institute (MYSS-UI), the second group of workers did not ask for the peer support (no peer support-experimental protocol) but was part of MYSS-UI, and the third group received standard organisational support from the Monteregie Youth Social Services (MYSS) (standard organisational protocol). Ethics and dissemination The protocol and informed consent form complied with the ethics guidelines of the MYSS-UI. The Research Ethics Board of MYSS-UI and MYSS reviewed and accepted the protocol as required. The results of the study will be published in peer-reviewed journals, presented at research and general public conferences, disseminated via a public report for the institute that funded the project and for all workers. Results of this study will influence decision making regarding intervention policies following PTE and peer support interventions may be expanded throughout the youth social services in Canada and worldwide. PMID:28647721

Emotion Regulation as the Foundation of Political Attitudes: Does Reappraisal Decrease Support for Conservative Policies?

PubMed Central

Lee, Jooa Julia; Sohn, Yunkyu; Fowler, James H.

2013-01-01

Cognitive scientists, behavior geneticists, and political scientists have identified several ways in which emotions influence political attitudes, and psychologists have shown that emotion regulation can have an important causal effect on physiology, cognition, and subjective experience. However, no work to date explores the possibility that emotion regulation may shape political ideology and attitudes toward policies. Here, we conduct four studies that investigate the role of a particular emotion regulation strategy – reappraisal in particular. Two observational studies show that individual differences in emotion regulation styles predict variation in political orientations and support for conservative policies. In the third study, we experimentally induce disgust as the target emotion to be regulated and show that use of reappraisal reduces the experience of disgust, thereby decreasing moral concerns associated with conservatism. In the final experimental study, we show that use of reappraisal successfully attenuates the relationship between trait-level disgust sensitivity and support for conservative policies. Our findings provide the first evidence of a critical link between emotion regulation and political attitudes. PMID:24367583

Quasi experimental designs in pharmacist intervention research.

PubMed

Krass, Ines

2016-06-01

Background In the field of pharmacist intervention research it is often difficult to conform to the rigorous requirements of the "true experimental" models, especially the requirement of randomization. When randomization is not feasible, a practice based researcher can choose from a range of "quasi-experimental designs" i.e., non-randomised and at time non controlled. Objective The aim of this article was to provide an overview of quasi-experimental designs, discuss their strengths and weaknesses and to investigate their application in pharmacist intervention research over the previous decade. Results In the literature quasi experimental studies may be classified into five broad categories: quasi-experimental design without control groups; quasi-experimental design that use control groups with no pre-test; quasi-experimental design that use control groups and pre-tests; interrupted time series and stepped wedge designs. Quasi-experimental study design has consistently featured in the evolution of pharmacist intervention research. The most commonly applied of all quasi experimental designs in the practice based research literature are the one group pre-post-test design and the non-equivalent control group design i.e., (untreated control group with dependent pre-tests and post-tests) and have been used to test the impact of pharmacist interventions in general medications management as well as in specific disease states. Conclusion Quasi experimental studies have a role to play as proof of concept, in the pilot phases of interventions when testing different intervention components, especially in complex interventions. They serve to develop an understanding of possible intervention effects: while in isolation they yield weak evidence of clinical efficacy, taken collectively, they help build a body of evidence in support of the value of pharmacist interventions across different practice settings and countries. However, when a traditional RCT is not feasible for logistical and/or ethical reasons researchers should endeavour to use the more robust of the quasi experimental designs.

The experimental evidence for parapsychological phenomena: A review.

PubMed

Cardeña, Etzel

2018-05-24

This article presents a comprehensive integration of current experimental evidence and theories about so-called parapsychological (psi) phenomena. Throughout history, people have reported events that seem to violate the common sense view of space and time. Some psychologists have been at the forefront of investigating these phenomena with sophisticated research protocols and theory, while others have devoted much of their careers to criticizing the field. Both stances can be explained by psychologists' expertise on relevant processes such as perception, memory, belief, and conscious and nonconscious processes. This article clarifies the domain of psi, summarizes recent theories from physics and psychology that present psi phenomena as at least plausible, and then provides an overview of recent/updated meta-analyses. The evidence provides cumulative support for the reality of psi, which cannot be readily explained away by the quality of the studies, fraud, selective reporting, experimental or analytical incompetence, or other frequent criticisms. The evidence for psi is comparable to that for established phenomena in psychology and other disciplines, although there is no consensual understanding of them. The article concludes with recommendations for further progress in the field including the use of project and data repositories, conducting multidisciplinary studies with enough power, developing further nonconscious measures of psi and falsifiable theories, analyzing the characteristics of successful sessions and participants, improving the ecological validity of studies, testing how to increase effect sizes, recruiting more researchers at least open to the possibility of psi, and situating psi phenomena within larger domains such as the study of consciousness. (PsycINFO Database Record (c) 2018 APA, all rights reserved).

Experimental anti-GBM disease as a tool for studying spontaneous lupus nephritis.

PubMed

Fu, Yuyang; Du, Yong; Mohan, Chandra

2007-08-01

Lupus nephritis is an immune-mediated disease, where antibodies and T cells both play pathogenic roles. Since spontaneous lupus nephritis in mouse models takes 6-12 months to manifest, there is an urgent need for a mouse model that can be used to delineate the pathogenic processes that lead to immune nephritis, over a quicker time frame. We propose that the experimental anti-glomerular basement membrane (GBM) disease model might be a suitable tool for uncovering some of the molecular steps underlying lupus nephritis. This article reviews the current evidence that supports the use of the experimental anti-GBM nephritis model for studying spontaneous lupus nephritis. Importantly, out of about 25 different molecules that have been specifically examined in the experimental anti-GBM model and also spontaneous lupus nephritis, all influence both diseases concordantly, suggesting that the experimental model might be a useful tool for unraveling the molecular basis of spontaneous lupus nephritis. This has important clinical implications, both from the perspective of genetic susceptibility as well as clinical therapeutics.

Formal Assurance Arguments: A Solution In Search of a Problem?

NASA Technical Reports Server (NTRS)

Graydon, Patrick J.

2015-01-01

An assurance case comprises evidence and argument showing how that evidence supports assurance claims (e.g., about safety or security). It is unsurprising that some computer scientists have proposed formalizing assurance arguments: most associate formality with rigor. But while engineers can sometimes prove that source code refines a formal specification, it is not clear that formalization will improve assurance arguments or that this benefit is worth its cost. For example, formalization might reduce the benefits of argumentation by limiting the audience to people who can read formal logic. In this paper, we present (1) a systematic survey of the literature surrounding formal assurance arguments, (2) an analysis of errors that formalism can help to eliminate, (3) a discussion of existing evidence, and (4) suggestions for experimental work to definitively answer the question.

Experimental evidence supports the abscess theory of development of radicular cysts.

PubMed

Nair, P N R; Sundqvist, Göran; Sjögren, Ulf

2008-08-01

The objective of this study was to experimentally induce inflammatory cysts in an animal model so as to test the hypothesis that radicular cysts develop via the "abscess pathway." Twenty-eight perforated custom-made Teflon cages were surgically implanted into defined locations in the back of 7 Sprague Dawley rats. A week after the implantation of the cages, a known quantity of freshly grown, close allogeneic oral keratinocytes in phosphate buffer solution (PBS) was injected into each cage. One cage per animal was treated as the control that received only epithelial cells. The remaining 3 cages of each animal were trials. Seven days post epithelial cell inoculation; a suspension of 0.2 mL of Fusobacterium nucleatum (10(8) bacteria per mL) was injected into each of the 3 trial cages. Two, 12, and 24 weeks after the inoculation of the bacteria, the cages were taken out, and the tissue contents were fixed and processed by correlative light and transmission electron microscopy. Sixteen of the 21 trial cages could be processed and yielded results. Inoculations of epithelial cells followed 1 week later by F. nucleatum into tissue cages resulted in the development inflammatory cysts in 2 of the 16 cages. The 2 cages contained a total of 4 cystic sites. None of the control cages showed the presence of any cyst-like pathology. Inflammatory cysts were induced by initiating acute inflammatory foci (abscess/necrotic area) by bacterial injection that got enclosed by a proliferating epithelium. This finding provides strong experimental evidence in support of the "abscess theory" of development of radicular cysts.

Drug repositioning for orphan genetic diseases through Conserved Anticoexpressed Gene Clusters (CAGCs)

PubMed Central

2013-01-01

Background The development of new therapies for orphan genetic diseases represents an extremely important medical and social challenge. Drug repositioning, i.e. finding new indications for approved drugs, could be one of the most cost- and time-effective strategies to cope with this problem, at least in a subset of cases. Therefore, many computational approaches based on the analysis of high throughput gene expression data have so far been proposed to reposition available drugs. However, most of these methods require gene expression profiles directly relevant to the pathologic conditions under study, such as those obtained from patient cells and/or from suitable experimental models. In this work we have developed a new approach for drug repositioning, based on identifying known drug targets showing conserved anti-correlated expression profiles with human disease genes, which is completely independent from the availability of ‘ad hoc’ gene expression data-sets. Results By analyzing available data, we provide evidence that the genes displaying conserved anti-correlation with drug targets are antagonistically modulated in their expression by treatment with the relevant drugs. We then identified clusters of genes associated to similar phenotypes and showing conserved anticorrelation with drug targets. On this basis, we generated a list of potential candidate drug-disease associations. Importantly, we show that some of the proposed associations are already supported by independent experimental evidence. Conclusions Our results support the hypothesis that the identification of gene clusters showing conserved anticorrelation with drug targets can be an effective method for drug repositioning and provide a wide list of new potential drug-disease associations for experimental validation. PMID:24088245

Pesticides, chemical and industrial exposures in relation to systemic lupus erythematosus

PubMed Central

Parks, Christine G.; De Roos, Anneclaire J.

2013-01-01

Growing evidence suggests exposure to chemicals and industrial pollutants may increase risk of SLE. Here we review research on SLE associations with occupational and industrial exposures, primarily drawing on studies in human populations and summarizing epidemiologic research published in the past decade. The association of occupational silica exposure with SLE is well established, but key questions remain, including the required dose and susceptibility factors, and SLE risk due to other silicate exposures. Research on SLE and other exposures is less well developed, though several potential associations merit further consideration due to the consistency of preliminary human findings, experimental animal research, and biologic plausibility. These include pesticides and solvents, for which experimental findings also support investigation of specific agents, including organochlorines and trichloroethylene. Experimental findings and biologic plausibility suggest research on SLE and occupational exposure to hydrocarbons (i.e., mineral oils) is warranted, especially given the widespread exposures in the population. Experimental and limited human findings support further investigation of SLE related to mercury exposure, especially in dental occupations. Research on environmental risk factors in risk-enriched cohorts (family based) is recommended, as is further investigation of exposures in relation to intermediate markers of effect (e.g., antinuclear antibodies), clinical features (e.g., nephritis) and outcomes. PMID:24763537

Reproductive interference and fecundity affect competitive interactions of sibling species with low mating barriers: experimental and theoretical evidence.

PubMed

Gebiola, M; Kelly, S E; Velten, L; Zug, R; Hammerstein, P; Giorgini, M; Hunter, M S

2017-12-01

When allopatric species with incomplete prezygotic isolation come into secondary contact, the outcome of their interaction is not easily predicted. The parasitoid wasp Encarsia suzannae (iES), infected by Cardinium inducing cytoplasmic incompatibility (CI), and its sibling species E. gennaroi (EG), not infected by bacterial endosymbionts, may have diverged because of the complementary action of CI and asymmetric hybrid incompatibilities. Whereas postzygotic isolation is now complete because of sterility of F1 hybrid progeny, prezygotic isolation is still incipient. We set up laboratory population cage experiments to evaluate the outcome of the interaction between ES and EG in two pairwise combinations: iES vs EG and cured ES (cES, where Cardinium was removed with antibiotics) vs EG. We also built a theoretical model aimed at exploring the role of life-history differences and asymmetric mating on competitive outcomes. In three of four cages in each treatment, ES dominated the interaction. We found evidence for reproductive interference, driven by asymmetric mating preferences, that gave a competitive edge to ES, the species that better discriminated against heterospecifics. However, we did not find the fecundity cost previously shown to be associated with Cardinium infection in iES. The model largely supported the experimental results. The finding of only a slight competitive edge of ES over EG in population cages suggests that in a more heterogeneous environment the species could coexist. This is supported by evidence that the two species coexist in sympatry, where preliminary data suggest reproductive character displacement may have reinforced postzygotic isolation.

Human Health Effects of Biphenyl: Key Findings and Scientific Issues

PubMed Central

Li, Zheng; Hogan, Karen A.; Cai, Christine; Rieth, Susan

2015-01-01

Background: In support of the Integrated Risk Information System (IRIS), the U.S. Environmental Protection Agency (EPA) has evaluated the human health hazards of biphenyl exposure. Objectives: We review key findings and scientific issues regarding expected human health effects of biphenyl. Methods: Scientific literature from 1926 through September 2012 was critically evaluated to identify potential human health hazards associated with biphenyl exposure. Key issues related to the carcinogenicity and noncancer health hazards of biphenyl were examined based on evidence from experimental animal bioassays and mechanistic studies. Discussion: Systematic consideration of experimental animal studies of oral biphenyl exposure took into account the variety of study designs (e.g., study sizes, exposure levels, and exposure durations) to reconcile differing reported results. The available mechanistic and toxicokinetic evidence supports the hypothesis that male rat urinary bladder tumors arise through urinary bladder calculi formation but is insufficient to hypothesize a mode of action for liver tumors in female mice. Biphenyl and its metabolites may induce genetic damage, but a role for genotoxicity in biphenyl-induced carcinogenicity has not been established. Conclusions: The available health effects data for biphenyl provides suggestive evidence for carcinogenicity in humans, based on increased incidences of male rat urinary bladder tumors at high exposure levels and on female mouse liver tumors. Kidney toxicity is also a potential human health hazard of biphenyl exposure. Citation: Li Z, Hogan KA, Cai C, Rieth S. 2016. Human health effects of biphenyl: key findings and scientific issues. Environ Health Perspect 124:703–712; http://dx.doi.org/10.1289/ehp.1509730 PMID:26529796

Evidence Base Update for Autism Spectrum Disorder.

PubMed

Smith, Tristram; Iadarola, Suzannah

2015-01-01

This evidence base update examines the level of empirical support for interventions for children with autism spectrum disorder (ASD) younger than 5 years old. It focuses on research published since a previous review in this journal (Rogers & Vismara, 2008 ). We identified psychological or behavioral interventions that had been manualized and evaluated in either (a) experimental or quasi-experimental group studies or (b) systematic reviews of single-subject studies. We extracted data from all studies that met these criteria and were published after the previous review. Interventions were categorized across two dimensions. First, primary theoretical principles included applied behavior analysis (ABA), developmental social-pragmatic (DSP), or both. Second, practice elements included scope (comprehensive or focused), modality (individual intervention with the child, parent training, or classrooms), and intervention targets (e.g., spoken language or alternative and augmentative communication). We classified two interventions as well-established (individual, comprehensive ABA and teacher-implemented, focused ABA + DSP), 3 as probably efficacious (individual, focused ABA for augmentative and alternative communication; individual, focused ABA + DSP; and focused DSP parent training), and 5 as possibly efficacious (individual, comprehensive ABA + DSP; comprehensive ABA classrooms; focused ABA for spoken communication; focused ABA parent training; and teacher-implemented, focused DSP). The evidence base for ASD interventions has grown substantially since 2008. An increasing number of interventions have some empirical support; others are emerging as potentially efficacious. Priorities for future research include improving outcome measures, developing interventions for understudied ASD symptoms (e.g., repetitive behaviors), pinpointing mechanisms of action in interventions, and adapting interventions for implementation with fidelity by community providers.

Protocol for an experimental investigation of the roles of oxytocin and social support in neuroendocrine, cardiovascular, and subjective responses to stress across age and gender

PubMed Central

2009-01-01

Background Substantial empirical evidence has demonstrated that individuals who are socially isolated or have few positive social connections seem to age at a faster rate and have more chronic diseases. Oxytocin is a neurohypophyseal hormone hypothesized to coordinate both the causes and effects of positive social interactions, and may be involved in positive physiological adaptations such as buffering the deleterious effects of stress and promoting resilience. The proposed research will examine whether and how oxytocin influences responses to stress in humans and will consider effects in relation to those of social support. Methods/Design Experimental research will be used to determine whether exogenously administered oxytocin (intranasal) influences psychological and physiological outcomes under conditions of stress across gender and age in adulthood. Hypotheses to be tested are: 1) Oxytocin ameliorates the deleterious neuroendocrine, cardiovascular, and subjective effects of stress; 2) Oxytocin and social support have similar and additive stress-buffering effects; 3) Oxytocin effects are stronger in women versus men; and 4) Oxytocin effects are similar across a range of adult ages. Hypotheses will be tested with a placebo-controlled, double-blind study using a sample of healthy men and women recruited from the community. Participants are randomly assigned to receive either oxytocin or placebo. They undergo a social stress manipulation with and without social support (randomly assigned), and outcome measures are obtained at multiple times during the procedure. Discussion Understanding the determinants of healthy aging is a major public health priority and identifying effective measures to prevent or delay the onset of chronic diseases is an important goal. Experimental research on oxytocin, social relationships, and health in adulthood will contribute to the scientific knowledge base for maximizing active life and health expectancy. At conclusion of the study we will have solid evidence concerning the effects of oxytocin on stress response and whether it has similar effects across age and gender groups. A neurobiological understanding of resilience can inform efforts for both prevention and intervention of diseases or problems common in later life. Trial registration Clinical trial identification number is NCT01011465. PMID:20025778

Study types and reliability of Real World Evidence compared with experimental evidence used in Polish reimbursement decision-making processes.

PubMed

Wilk, N; Wierzbicka, N; Skrzekowska-Baran, I; Moćko, P; Tomassy, J; Kloc, K

2017-04-01

The aim of this study was to identify the relationship and impact between Real World Evidence (RWE) and experimental evidence (EE) in Polish decision-making processes for the drugs from selected Anatomical Therapeutic Chemical (ATC) groups. Descriptive study. A detailed analysis was performed for 58 processes from five ATC code groups in which RWE for effectiveness, or effectiveness and safety were cited in Agency for Health Technology Assessment and Tariff System's (AOTMiT) documents published between January 2012 and September 2015: Verification Analysis of AOTMiT, Statement of the Transparency Council of AOTMiT, and Recommendation of the President of AOTMiT. In 62% of the cases, RWE supported the EE and confirmed its main conclusions. The majority of studies in the EE group showed to be RCTs (97%), and the RWE group included mainly cohort studies (89%). There were more studies without a control group within RWE compared with the EE group (10% vs 1%). Our results showed that EE are more often assessed using Jadad, NICE or NOS scale by AOTMiT compared with RWE (93% vs 48%). When the best evidence within a given decision-making process is analysed, half of RWE and two-thirds of EE are considered high quality evidence. RWE plays an important role in the decision-making processes on public funding of drugs in Poland, contributing to nearly half (45%) of all the evidence considered. There exist such processes in which the proportion of RWE is dominant, with one process showing RWE as the only evidence presented. Copyright © 2016 The Royal Society for Public Health. Published by Elsevier Ltd. All rights reserved.

Type I interferon causes thrombotic microangiopathy by a dose-dependent toxic effect on the microvasculature

PubMed Central

Kavanagh, David; Jury, Alexa; Williams, Jac; Scolding, Neil; Bellamy, Chris; Gunther, Claudia; Ritchie, Diane; Gale, Daniel P.; Kanwar, Yashpal S.; Challis, Rachel; Buist, Holly; Overell, James; Weller, Belinda; Flossmann, Oliver; Blunden, Mark; Meyer, Eric P.; Krucker, Thomas; Evans, Stephen J. W.; Campbell, Iain L.; Jackson, Andrew P.; Chandran, Siddharthan

2016-01-01

Many drugs have been reported to cause thrombotic microangiopathy (TMA), yet evidence supporting a direct association is often weak. In particular, TMA has been reported in association with recombinant type I interferon (IFN) therapies, with recent concern regarding the use of IFN in multiple sclerosis patients. However, a causal association has yet to be demonstrated. Here, we adopt a combined clinical and experimental approach to provide evidence of such an association between type I IFN and TMA. We show that the clinical phenotype of cases referred to a national center is uniformly consistent with a direct dose-dependent drug-induced TMA. We then show that dose-dependent microvascular disease is seen in a transgenic mouse model of IFN toxicity. This includes specific microvascular pathological changes seen in patient biopsies and is dependent on transcriptional activation of the IFN response through the type I interferon α/β receptor (IFNAR). Together our clinical and experimental findings provide evidence of a causal link between type I IFN and TMA. As such, recombinant type I IFN therapies should be stopped at the earliest stage in patients who develop this complication, with implications for risk mitigation. PMID:27663672

What's in a norm? Sources and processes of norm change.

PubMed

Paluck, Elizabeth Levy

2009-03-01

This reply to the commentary by E. Staub and L. A. Pearlman (2009) revisits the field experimental results of E. L. Paluck (2009). It introduces further evidence and theoretical elaboration supporting Paluck's conclusion that exposure to a reconciliation-themed radio soap opera changed perceptions of social norms and behaviors, not beliefs. Experimental and longitudinal survey evidence reinforces the finding that the radio program affected socially shared perceptions of typical or prescribed behavior-that is, social norms. Specifically, measurements of perceptions of social norms called into question by Staub and Pearlman are shown to correlate with perceptions of public opinion and public, not private, behaviors. Although measurement issues and the mechanisms of the radio program's influence merit further testing, theory and evidence point to social interactions and emotional engagement, not individual education, as the likely mechanisms of change. The present exchange makes salient what is at stake in this debate: a model of change based on learning and personal beliefs versus a model based on group influence and social norms. These theoretical models recommend very different strategies for prejudice and conflict reduction. Future field experiments should attempt to adjudicate between these models by testing relevant policies in real-world settings.

Efficacy of aquatic therapy for multiple sclerosis: a systematic review.

PubMed

Corvillo, Iluminada; Varela, Enrique; Armijo, Francisco; Alvarez-Badillo, Antonio; Armijo, Onica; Maraver, Francisco

2017-12-01

Multiple sclerosis (MS) is a chronic, inflammatory, progressive, disabling autoimmune disease affecting the central nervous system. Symptoms and signs of MS vary widely and patients may lose their ability to walk. To date the benefits of aquatic therapy often used for rehabilitation in MS patients have not been reviewed. The aim of this study was to systematically review the current state of aquatic treatment for persons with MS (hydrotherapy, aquatic therapy, aquatic exercises, spa therapy) and to evaluate the scientific evidence supporting the benefits of this therapeutic option. The databases PubMed, Scopus, WoS and PEDro were searched to identify relevant reports published from January 1, 2011 to April 30, 2016. Of 306 articles identified, only 10 fulfilled the inclusion criteria: 5 randomized controlled, 2 simple randomized quasi-experimental, 1 semi-experimental, 1 blind controlled pilot and 1 pilot. Evidence that aquatic treatment improves quality of life in affected patients was very good in two studies, good in four, fair in two and weak in two.

Stepping stones in the electron transport from cells to electrodes in Geobacter sulfurreducens biofilms.

PubMed

Bonanni, Pablo Sebastián; Massazza, Diego; Busalmen, Juan Pablo

2013-07-07

Geobacter sulfurreducens bacteria grow on biofilms and have the particular ability of using polarized electrodes as the final electron acceptor of their respiratory chain. In these biofilms, electrons are transported through distances of more than 50 μm before reaching the electrode. The way in which electrons are transported across the biofilm matrix through such large distances remains under intense discussion. None of the two mechanisms proposed for explaining the process, electron hopping through outer membrane cytochromes and metallic like conduction through conductive PilA filaments, can account for all the experimental evidence collected so far. Aiming at providing new elements for understanding the basis for electron transport, in this perspective article we present a modelled structure of Geobacter pilus. Its analysis in combination with already existing experimental evidence gives support to the proposal of the "stepping stone" mechanism, in which the combined action of pili and cytochromes allows long range electron transport through the biofilm.

Bridging the gap between evidence-based innovation and national health-sector reform in Ghana.

PubMed

Awoonor-Williams, John Koku; Feinglass, Ellie S; Tobey, Rachel; Vaughan-Smith, Maya N; Nyonator, Frank K; Jones, Tanya C

2004-09-01

Although experimental trials often identify optimal strategies for improving community health, transferring operational innovation from well-funded research programs to resource-constrained settings often languishes. Because research initiatives are based in institutions equipped with unique resources and staff capabilities, results are often dismissed by decisionmakers as irrelevant to large-scale operations and national health policy. This article describes an initiative undertaken in Nkwanta District, Ghana, focusing on this problem. The Nkwanta District initiative is a critical link between the experimental study conducted in Navrongo, Ghana, and a national effort to scale up the innovations developed in that study. A 2002 Nkwanta district-level survey provides the basis for assessing the likelihood that the Navrongo model is replicable elsewhere in Ghana. The effect of community-based health planning and services exposure on family planning and safe-motherhood indicators supports the hypothesis that Navrongo effects are transferable to impoverished rural settings elsewhere, confirming the need for strategies to bridge the gap between Navrongo evidence-based innovation and national health-sector reform.

Experimental Evidence of Kinetic Effects in Indirect-Drive Inertial Confinement Fusion Hohlraums

NASA Astrophysics Data System (ADS)

Shan, L. Q.; Cai, H. B.; Zhang, W. S.; Tang, Q.; Zhang, F.; Song, Z. F.; Bi, B.; Ge, F. J.; Chen, J. B.; Liu, D. X.; Wang, W. W.; Yang, Z. H.; Qi, W.; Tian, C.; Yuan, Z. Q.; Zhang, B.; Yang, L.; Jiao, J. L.; Cui, B.; Zhou, W. M.; Cao, L. F.; Zhou, C. T.; Gu, Y. Q.; Zhang, B. H.; Zhu, S. P.; He, X. T.

2018-05-01

We present the first experimental evidence supported by simulations of kinetic effects launched in the interpenetration layer between the laser-driven hohlraum plasma bubbles and the corona plasma of the compressed pellet at the Shenguang-III prototype laser facility. Solid plastic capsules were coated with carbon-deuterium layers; as the implosion neutron yield is quenched, DD fusion yield from the corona plasma provides a direct measure of the kinetic effects inside the hohlraum. An anomalous large energy spread of the DD neutron signal (˜282 keV ) and anomalous scaling of the neutron yield with the thickness of the carbon-deuterium layers cannot be explained by the hydrodynamic mechanisms. Instead, these results can be attributed to kinetic shocks that arise in the hohlraum-wall-ablator interpenetration region, which result in efficient acceleration of the deuterons (˜28.8 J , 0.45% of the total input laser energy). These studies provide novel insight into the interactions and dynamics of a vacuum hohlraum and near-vacuum hohlraum.

Tocopherols in cancer: An update.

PubMed

Das Gupta, Soumyasri; Suh, Nanjoo

2016-06-01

Tocopherols exist in four forms designated as α, β, δ, and γ. Due to their strong antioxidant properties, tocopherols have been suggested to reduce the risk of cancer. Cancer prevention studies with tocopherols have mostly utilized α-tocopherol. Large-scale clinical trials with α-tocopherol provided inconsistent results regarding the cancer-preventive activities of tocopherols. This review summarizes our current understanding of the anticancer activities of different forms of tocopherols based on follow-up of the clinical trials, recent epidemiological evidences, and experimental studies using in vitro and in vivo models. The experimental data provide strong evidence in support of the anticancer activities of δ-tocopherol, γ-tocopherol, and the natural tocopherol mixture rich in γ-tocopherol, γ-TmT, over α-tocopherol. Such outcomes emphasize the need for detailed investigation into the cancer-preventive activities of different forms of tocopherols to provide a strong rationale for intervention studies in the future. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Evidence for rotation of V1-ATPase

PubMed Central

Imamura, Hiromi; Nakano, Masahiro; Noji, Hiroyuki; Muneyuki, Eiro; Ohkuma, Shoji; Yoshida, Masasuke; Yokoyama, Ken

2003-01-01

VoV1-ATPase is responsible for acidification of eukaryotic intracellular compartments and ATP synthesis of Archaea and some eubacteria. From the similarity to FoF1-ATP synthase, VoV1-ATPase has been assumed to be a rotary motor, but to date there are no experimental data to support this. Here we visualized the rotation of single molecules of V1-ATPase, a catalytic subcomplex of VoV1-ATPase. V1-ATPase from Thermus thermophilus was immobilized onto a glass surface, and a bead was attached to the D or F subunit through the biotin-streptavidin linkage. In both cases we observed ATP-dependent rotations of beads, the direction of which was always counterclockwise viewed from the membrane side. Given that three ATP molecules are hydrolyzed per one revolution, rates of rotation agree consistently with rates of ATP hydrolysis at saturating ATP concentrations. This study provides experimental evidence that VoV1-ATPase is a rotary motor and that both D and F subunits constitute a rotor shaft. PMID:12598655

Experimental evidence for superionic water ice using shock compression

NASA Astrophysics Data System (ADS)

Millot, Marius; Hamel, Sebastien; Rygg, J. Ryan; Celliers, Peter M.; Collins, Gilbert W.; Coppari, Federica; Fratanduono, Dayne E.; Jeanloz, Raymond; Swift, Damian C.; Eggert, Jon H.

2018-03-01

In stark contrast to common ice, Ih, water ice at planetary interior conditions has been predicted to become superionic with fast-diffusing (that is, liquid-like) hydrogen ions moving within a solid lattice of oxygen. Likely to constitute a large fraction of icy giant planets, this extraordinary phase has not been observed in the laboratory. Here, we report laser-driven shock-compression experiments on water ice VII. Using time-resolved optical pyrometry and laser velocimetry measurements as well as supporting density functional theory-molecular dynamics (DFT-MD) simulations, we document the shock equation of state of H2O to unprecedented extreme conditions and unravel thermodynamic signatures showing that ice melts near 5,000 K at 190 GPa. Optical reflectivity and absorption measurements also demonstrate the low electronic conductivity of ice, which, combined with previous measurements of the total electrical conductivity under reverberating shock compression, provides experimental evidence for superionic conduction in water ice at planetary interior conditions, verifying a 30-year-old prediction.

Chemopreventive properties of 3,3′-diindolylmethane in breast cancer: evidence from experimental and human studies

PubMed Central

Ho, Emily; Strom, Meghan B.

2016-01-01

Diet is a modifiable factor associated with the risk of several cancers, with convincing evidence showing a link between diet and breast cancer. The role of bioactive compounds of food origin, including those found in cruciferous vegetables, is an active area of research in cancer chemoprevention. This review focuses on 3,3′-diindolylmethane (DIM), the major bioactive indole in crucifers. Research of the cancer-preventive activity of DIM has yielded basic mechanistic, animal, and human trial data. Further, this body of evidence is largely supported by observational studies. Bioactive DIM has demonstrated chemopreventive activity in all stages of breast cancer carcinogenesis. This review describes current evidence related to the metabolism and mechanisms of DIM involved in the prevention of breast cancer. Importantly, this review also focuses on current evidence from human observational and intervention trials that have contributed to a greater understanding of exposure estimates that will inform recommendations for DIM intake. PMID:27261275

Effect of chest compressions only during experimental basic life support on alveolar collapse and recruitment.

PubMed

Markstaller, Klaus; Rudolph, Annette; Karmrodt, Jens; Gervais, Hendrik W; Goetz, Rolf; Becher, Anja; David, Matthias; Kempski, Oliver S; Kauczor, Hans-Ulrich; Dick, Wolfgang F; Eberle, Balthasar

2008-10-01

The importance of ventilatory support during cardiac arrest and basic life support is controversial. This experimental study used dynamic computed tomography (CT) to assess the effects of chest compressions only during cardiopulmonary resuscitation (CCO-CPR) on alveolar recruitment and haemodynamic parameters in porcine model of ventricular fibrillation. Twelve anaesthetized pigs (26+/-1 kg) were randomly assigned to one of the following groups: (1) intermittent positive pressure ventilation (IPPV) both during basic life support and advanced cardiac life support, or (2) CCO during basic life support and IPPV during advanced cardiac life support. Measurements were acquired at baseline prior to cardiac arrest, during basic life support, during advanced life support, and after return of spontaneous circulation (ROSC), as follows: dynamic CT series, arterial and central venous pressures, blood gases, and regional organ blood flow. The ventilated and atelectatic lung area was quantified from dynamic CT images. Differences between groups were analyzed using the Kruskal-Wallis test, and a p<0.05 was considered statistically significant. IPPV was associated with cyclic alveolar recruitment and de-recruitment. Compared with controls, the CCO-CPR group had a significantly larger mean fractional area of atelectasis (p=0.009), and significantly lower PaO2 (p=0.002) and mean arterial pressure (p=0.023). The increase in mean atelectatic lung area observed during basic life support in the CCO-CPR group remained clinically relevant throughout the subsequent advanced cardiac life support period and following ROSC, and was associated with prolonged impaired haemodynamics. No inter-group differences in myocardial and cerebral blood flow were observed. A lack of ventilation during basic life support is associated with excessive atelectasis, arterial hypoxaemia and compromised CPR haemodynamics. Moreover, these detrimental effects remain evident even after restoration of IPPV.

Effectiveness of the use of question-driven levels of inquiry based instruction (QD-LOIBI) assisted visual multimedia supported teaching material on enhancing scientific explanation ability senior high school students

NASA Astrophysics Data System (ADS)

Suhandi, A.; Muslim; Samsudin, A.; Hermita, N.; Supriyatman

2018-05-01

In this study, the effectiveness of the use of Question-Driven Levels of Inquiry Based Instruction (QD-LOIBI) assisted visual multimedia supported teaching materials on enhancing senior high school students scientific explanation ability has been studied. QD-LOIBI was designed by following five-levels of inquiry proposed by Wenning. Visual multimedia used in teaching materials included image (photo), virtual simulation and video phenomena. QD-LOIBI assisted teaching materials supported by visual multimedia were tried out on senior high school students at one high school in one district in West Java. A quasi-experiment method with design one experiment group (n = 31) and one control group (n = 32) were used. Experimental group were given QD-LOIBI assisted teaching material supported by visual multimedia, whereas the control group were given QD-LOIBI assisted teaching materials not supported visual multimedia. Data on the ability of scientific explanation in both groups were collected by scientific explanation ability test in essay form concerning kinetic gas theory concept. The results showed that the number of students in the experimental class that has increased the category and quality of scientific explanation is greater than in the control class. These results indicate that the use of multimedia supported instructional materials developed for implementation of QD-LOIBI can improve students’ ability to provide explanations supported by scientific evidence gained from practicum activities and applicable concepts, laws, principles or theories.

Quasi-experimental evaluation of a telephone-based peer support intervention for maternal depression.

PubMed

Letourneau, Nicole; Secco, Loretta; Colpitts, Jennifer; Aldous, Sarah; Stewart, Miriam; Dennis, Cindy-Lee

2015-07-01

To evaluate the effect of telephone-based peer support on maternal depression and social support Postpartum depression is a global health concern and lack of treatment options mean many mothers are depressed beyond the first year after birth. Strong evidence has shown telephone-based peer support, provided by a mother recovered from depression, effectively improves depression outcomes. This model has not been tested with mothers with depression any time up to two years postpartum. Quasi-experimental, one group pre-test, posttest. The study population was mothers in New Brunswick, Canada with depression up to 24 months after delivery. The sample (N = 64) was recruited between May 2011-October 2013. Peer volunteers recovered from postpartum depression were trained and delivered an average of 8·84 (Range 1-13) support telephone calls. Depression and social support outcomes were assessed at intervention mid-point (average 7·43 weeks, n = 37) and end (average 13·9 weeks, n = 34). Mean depression significantly declined from baseline, 15·4 (N = 49), to mid-point, 8·30 and end of the study, 6·26. At mid-point 8·1% (n = 3/37) of mothers were depressed and at endpoint 11·8% (4/34) were depressed suggesting some relapse. Perceptions of social support significantly improved and higher support was significantly related with lower depression symptoms. Findings offer promise that telephone-based peer support is effective for both early postpartum depression and maternal depression up to two years after delivery. © 2015 John Wiley & Sons Ltd.

Honest sexual signaling in turtles: experimental evidence of a trade-off between immune response and coloration in red-eared sliders Trachemys scripta elegans.

PubMed

Ibáñez, Alejandro; Polo-Cavia, Nuria; López, Pilar; Martín, José

2014-10-01

Sexual signals can be evolutionarily stable if they are honest and condition dependent or costly to the signaler. One possible cost is the existence of a trade-off between maintaining the immune system and the elaboration of ornaments. This hypothesis has been experimentally tested in some groups of animals but not in others such as turtles. We experimentally challenged the immune system of female red-eared sliders Trachemys scripta elegans, with a bacterial antigen (lipopolysaccharide (LPS)) without pathogenic effects to explore whether the immune activation affected visual colorful ornaments of the head. The LPS injection altered the reflectance patterns of color ornaments. In comparison to the control animals, the yellow chin stripes of injected animals exhibited (1) reduced brightness, (2) lower long wavelength (>470 nm) reflectance, and (3) lower values for carotenoid chroma. The postorbital patches of injected individuals also showed reduced very long wavelength (>570 nm) reflectance but did not change in carotenoid chroma. Thus, experimental turtles showed darker and less "yellowish" chin stripes and less "reddish" postorbital patches at the end of the experiment, whereas control turtles did not change their coloration. This is the first experimental evidence supporting the existence of a trade-off between the immune system and the expression of visual ornaments in turtles. We suggest that this trade-off may allow turtles to honestly signal individual quality via characteristics of coloration, which may have an important role in intersexual selection processes.

Honest sexual signaling in turtles: experimental evidence of a trade-off between immune response and coloration in red-eared sliders Trachemys scripta elegans

NASA Astrophysics Data System (ADS)

Ibáñez, Alejandro; Polo-Cavia, Nuria; López, Pilar; Martín, José

2014-10-01

Sexual signals can be evolutionarily stable if they are honest and condition dependent or costly to the signaler. One possible cost is the existence of a trade-off between maintaining the immune system and the elaboration of ornaments. This hypothesis has been experimentally tested in some groups of animals but not in others such as turtles. We experimentally challenged the immune system of female red-eared sliders Trachemys scripta elegans, with a bacterial antigen (lipopolysaccharide (LPS)) without pathogenic effects to explore whether the immune activation affected visual colorful ornaments of the head. The LPS injection altered the reflectance patterns of color ornaments. In comparison to the control animals, the yellow chin stripes of injected animals exhibited (1) reduced brightness, (2) lower long wavelength (>470 nm) reflectance, and (3) lower values for carotenoid chroma. The postorbital patches of injected individuals also showed reduced very long wavelength (>570 nm) reflectance but did not change in carotenoid chroma. Thus, experimental turtles showed darker and less "yellowish" chin stripes and less "reddish" postorbital patches at the end of the experiment, whereas control turtles did not change their coloration. This is the first experimental evidence supporting the existence of a trade-off between the immune system and the expression of visual ornaments in turtles. We suggest that this trade-off may allow turtles to honestly signal individual quality via characteristics of coloration, which may have an important role in intersexual selection processes.

Investigation of effective strategies for developing creative science thinking

NASA Astrophysics Data System (ADS)

Yang, Kuay-Keng; Lee, Ling; Hong, Zuway-R.; Lin, Huann-shyang

2016-09-01

The purpose of this study was to explore the effectiveness of the creative inquiry-based science teaching on students' creative science thinking and science inquiry performance. A quasi-experimental design consisting one experimental group (N = 20) and one comparison group (N = 24) with pretest and post-test was conducted. The framework of the intervention focused on potential strategies such as promoting divergent and convergent thinking and providing an open, inquiry-based learning environment that are recommended by the literature. Results revealed that the experimental group students outperformed their counterparts in the comparison group on the performances of science inquiry and convergent thinking. Additional qualitative data analyses from classroom observations and case teacher interviews identified supportive teaching strategies (e.g. facilitating associative thinking, sharing impressive ideas, encouraging evidence-based conclusions, and reviewing and commenting on group presentations) for developing students' creative science thinking.

Modeling Criminal Activity in Urban Landscapes

NASA Astrophysics Data System (ADS)

Brantingham, Patricia; Glässer, Uwe; Jackson, Piper; Vajihollahi, Mona

Computational and mathematical methods arguably have an enormous potential for serving practical needs in crime analysis and prevention by offering novel tools for crime investigations and experimental platforms for evidence-based policy making. We present a comprehensive formal framework and tool support for mathematical and computational modeling of criminal behavior to facilitate systematic experimental studies of a wide range of criminal activities in urban environments. The focus is on spatial and temporal aspects of different forms of crime, including opportunistic and serial violent crimes. However, the proposed framework provides a basis to push beyond conventional empirical research and engage the use of computational thinking and social simulations in the analysis of terrorism and counter-terrorism.

Multiple Openings and Competitiveness of Forward Markets: Experimental Evidence

PubMed Central

Ferreira, José Luis; Kujal, Praveen; Rassenti, Stephen

2016-01-01

We test the competition enhancing effect of selling forward in experimental Cournot duopoly and quadropoly with multiple forward markets. We find that two forward periods yields competitive outcomes and that the results are very close to the predicted theoretical results for quantity setting duopolies and quadropolies. Our experiments lend strong support to the hypothesis that forward markets are competition enhancing. We then test a new market that allows for endogenously determined indefinitely many forward periods that only close when sellers coordinate on selling a zero amount in a forward market. We find that the outcomes under an endogenous close rule are also very competitive. These results hold for both duopolies and quadropolies. PMID:27442516

A study of the local pressure field in turbulent shear flow and its relation to aerodynamic noise generation

NASA Technical Reports Server (NTRS)

Jones, B. G.; Planchon, H. P., Jr.

1973-01-01

Work during the period of this report has been in three areas: (1) pressure transducer error analysis, (2) fluctuating velocity and pressure measurements in the NASA Lewis 6-inch diameter quiet jet facility, and (3) measurement analysis. A theory was developed and experimentally verified to quantify the pressure transducer velocity interference error. The theory and supporting experimental evidence show that the errors are a function of the velocity field's turbulent structure. It is shown that near the mixing layer center the errors are negligible. Turbulent velocity and pressure measurements were made in the NASA Lewis quiet jet facility. Some preliminary results are included.

From action to language: comparative perspectives on primate tool use, gesture and the evolution of human language

PubMed Central

Steele, James; Ferrari, Pier Francesco; Fogassi, Leonardo

2012-01-01

The papers in this Special Issue examine tool use and manual gestures in primates as a window on the evolution of the human capacity for language. Neurophysiological research has supported the hypothesis of a close association between some aspects of human action organization and of language representation, in both phonology and semantics. Tool use provides an excellent experimental context to investigate analogies between action organization and linguistic syntax. Contributors report and contextualize experimental evidence from monkeys, great apes, humans and fossil hominins, and consider the nature and the extent of overlaps between the neural representations of tool use, manual gestures and linguistic processes. PMID:22106422

An audience research study to disseminate evidence about comprehensive state mental health parity legislation to US State policymakers: protocol.

PubMed

Purtle, Jonathan; Lê-Scherban, Félice; Shattuck, Paul; Proctor, Enola K; Brownson, Ross C

2017-06-26

A large proportion of the US population has limited access to mental health treatments because insurance providers limit the utilization of mental health services in ways that are more restrictive than for physical health services. Comprehensive state mental health parity legislation (C-SMHPL) is an evidence-based policy intervention that enhances mental health insurance coverage and improves access to care. Implementation of C-SMHPL, however, is limited. State policymakers have the exclusive authority to implement C-SMHPL, but sparse guidance exists to inform the design of strategies to disseminate evidence about C-SMHPL, and more broadly, evidence-based treatments and mental illness, to this audience. The aims of this exploratory audience research study are to (1) characterize US State policymakers' knowledge and attitudes about C-SMHPL and identify individual- and state-level attributes associated with support for C-SMHPL; and (2) integrate quantitative and qualitative data to develop a conceptual framework to disseminate evidence about C-SMHPL, evidence-based treatments, and mental illness to US State policymakers. The study uses a multi-level (policymaker, state), mixed method (QUAN→qual) approach and is guided by Kingdon's Multiple Streams Framework, adapted to incorporate constructs from Aarons' Model of Evidence-Based Implementation in Public Sectors. A multi-modal survey (telephone, post-mail, e-mail) of 600 US State policymakers (500 legislative, 100 administrative) will be conducted and responses will be linked to state-level variables. The survey will span domains such as support for C-SMHPL, knowledge and attitudes about C-SMHPL and evidence-based treatments, mental illness stigma, and research dissemination preferences. State-level variables will measure factors associated with C-SMHPL implementation, such as economic climate and political environment. Multi-level regression will determine the relative strength of individual- and state-level variables on policymaker support for C-SMHPL. Informed by survey results, semi-structured interviews will be conducted with approximately 50 US State policymakers to elaborate upon quantitative findings. Then, using a systematic process, quantitative and qualitative data will be integrated and a US State policymaker-focused C-SMHPL dissemination framework will be developed. Study results will provide the foundation for hypothesis-driven, experimental studies testing the effects of different dissemination strategies on state policymakers' support for, and implementation of, evidence-based mental health policy interventions.

Electrochemical Catalyst-Support Effects and Their Stabilizing Role for IrOx Nanoparticle Catalysts during the Oxygen Evolution Reaction.

PubMed

Oh, Hyung-Suk; Nong, Hong Nhan; Reier, Tobias; Bergmann, Arno; Gliech, Manuel; Ferreira de Araújo, Jorge; Willinger, Elena; Schlögl, Robert; Teschner, Detre; Strasser, Peter

2016-09-28

Redox-active support materials can help reduce the noble-metal loading of a solid chemical catalyst while offering electronic catalyst-support interactions beneficial for catalyst durability. This is well known in heterogeneous gas-phase catalysis but much less discussed for electrocatalysis at electrified liquid-solid interfaces. Here, we demonstrate experimental evidence for electronic catalyst-support interactions in electrochemical environments and study their role and contribution to the corrosion stability of catalyst/support couples. Electrochemically oxidized Ir oxide nanoparticles, supported on high surface area carbons and oxides, were selected as model catalyst/support systems for the electrocatalytic oxygen evolution reaction (OER). First, the electronic, chemical, and structural state of the catalyst/support couple was compared using XANES, EXAFS, TEM, and depth-resolved XPS. While carbon-supported oxidized Ir particle showed exclusively the redox state (+4), the Ir/IrOx/ATO system exhibited evidence of metal/metal-oxide support interactions (MMOSI) that stabilized the metal particles on antimony-doped tin oxide (ATO) in sustained lower Ir oxidation states (Ir(3.2+)). At the same time, the growth of higher valent Ir oxide layers that compromise catalyst stability was suppressed. Then the electrochemical stability and the charge-transfer kinetics of the electrocatalysts were evaluated under constant current and constant potential conditions, where the analysis of the metal dissolution confirmed that the ATO support mitigates Ir(z+) dissolution thanks to a stronger MMOSI effect. Our findings raise the possibility that MMOSI effects in electrochemistry-largely neglected in the past-may be more important for a detailed understanding of the durability of oxide-supported nanoparticle OER catalysts than previously thought.

Genetic Contributions to Clinical Pain and Analgesia: Avoiding Pitfalls in Genetic Research

PubMed Central

Kim, Hyungsuk; Clark, David; Dionne, Raymond A.

2010-01-01

Understanding the genetic basis of human variations in pain is critical to elucidating the molecular basis of pain sensitivity, variable responses to analgesic drugs, and, ultimately, to individualized treatment of pain and improved public health. With the help of recently accumulated knowledge and advanced technologies, pain researchers hope to gain insight into genetic mechanisms of pain and eventually apply this knowledge to pain treatment. Perspective We critically reviewed the published literature to examine the strength of evidence supporting genetic influences on clinical and human experimental pain. Based on this evidence and the experience of false associations that have occurred in other related disciplines, we provide recommendations for avoiding pitfalls in pain genetic research. PMID:19559388

Evidence for a shear horizontal resonance in supported thin films

NASA Astrophysics Data System (ADS)

Zhang, X.; Manghnani, M. H.; Every, A. G.

2000-07-01

We report evidence for a different type of acoustic film excitation, identified as a shear horizontal resonance, in amorphous silicon oxynitride films on GaAs substrate. Observation of this excitation has been carried out using surface Brillouin scattering of light. A Green's function formalism is used for analyzing the experimental spectra, and successfully simulates the spectral features associated with this mode. The attributes of this mode are described; these include its phase velocity which is nearly equal to that of a bulk shear wave propagating parallel to the surface and is almost independent of film thickness and scattering angle, its localization mainly in the film, and its polarization in the shear horizontal direction.

Effects of electrical stimulation on House-Brackmann scores in early Bell's palsy.

PubMed

Alakram, Prisha; Puckree, Threethambal

2010-04-22

ABSTRACT Limited evidence may support the application of electrical stimulation in the subacute and chronic stages of facial palsy, yet some physiotherapists in South Africa have been applying this modality in the acute stage in the absence of published evidence of clinical efficacy. This preliminary study's aim was to determine the safety and potential efficacy of applying electrical stimulation to the facial muscles during the early phase of Bells palsy. A pretest posttest control vs. experimental groups design composed of 16 patients with Bell's palsy of less than 30 days' duration. Adult patients with clinical diagnosis of Bell's palsy were systematically (every second patient) allocated to the control and experimental groups. Each group (n = 8) was pretested and posttested using the House-Brackmann index. Both groups were treated with heat, massage, exercises, and a home program. The experimental group also received electrical stimulation. The House-Brackmann Scale of the control group improved between 17% and 50% with a mean of 30%. The scores of the experimental group ranged between 17% and 75% with a mean of 37%. The difference between the groups was not statistically significant (two-tailed p = 0.36). Electrical stimulation as used in this study during the acute phase of Bell's palsy is safe but may not have added value over spontaneous recovery and multimodal physiotherapy. A larger sample size or longer stimulation time or both should be investigated.

Regression of devil facial tumour disease following immunotherapy in immunised Tasmanian devils

PubMed Central

Tovar, Cesar; Pye, Ruth J.; Kreiss, Alexandre; Cheng, Yuanyuan; Brown, Gabriella K.; Darby, Jocelyn; Malley, Roslyn C.; Siddle, Hannah V. T.; Skjødt, Karsten; Kaufman, Jim; Silva, Anabel; Baz Morelli, Adriana; Papenfuss, Anthony T.; Corcoran, Lynn M.; Murphy, James M.; Pearse, Martin J.; Belov, Katherine; Lyons, A. Bruce; Woods, Gregory M.

2017-01-01

Devil facial tumour disease (DFTD) is a transmissible cancer devastating the Tasmanian devil (Sarcophilus harrisii) population. The cancer cell is the ‘infectious’ agent transmitted as an allograft by biting. Animals usually die within a few months with no evidence of antibody or immune cell responses against the DFTD allograft. This lack of anti-tumour immunity is attributed to an absence of cell surface major histocompatibility complex (MHC)-I molecule expression. While the endangerment of the devil population precludes experimentation on large experimental groups, those examined in our study indicated that immunisation and immunotherapy with DFTD cells expressing surface MHC-I corresponded with effective anti-tumour responses. Tumour engraftment did not occur in one of the five immunised Tasmanian devils, and regression followed therapy of experimentally induced DFTD tumours in three Tasmanian devils. Regression correlated with immune cell infiltration and antibody responses against DFTD cells. These data support the concept that immunisation of devils with DFTD cancer cells can successfully induce humoral responses against DFTD and trigger immune-mediated regression of established tumours. Our findings support the feasibility of a protective DFTD vaccine and ultimately the preservation of the species. PMID:28276463

May God Guide Our Guns : Visualizing Supernatural Aid Heightens Team Confidence in a Paintball Battle Simulation.

PubMed

Pollack, Jeremy; Holbrook, Colin; Fessler, Daniel M T; Sparks, Adam Maxwell; Zerbe, James G

2018-06-18

The perceived support of supernatural agents has been historically, ethnographically, and theoretically linked with confidence in engaging in violent intergroup conflict. However, scant experimental investigations of such links have been reported to date, and the extant evidence derives largely from indirect laboratory methods of limited ecological validity. Here, we experimentally tested the hypothesis that perceived supernatural aid would heighten inclinations toward coalitional aggression using a realistic simulated coalitional combat paradigm: competitive team paintball. In a between-subjects design, US paintball players recruited for the study were experimentally primed with thoughts of supernatural support using a guided visualization exercise analogous to prayer, or with a control visualization of a nature scene. The participants then competed in a team paintball battle game modeled after "Capture the Flag." Immediately before and after the battle, participants completed surveys assessing confidence in their coalitional and personal battle performance. Participants assessed their coalition's prospects of victory and performance more positively after visualizing supernatural aid. Participants primed with supernatural support also reported inflated assessments of their own performance. Importantly, however, covarying increases in assessments of their overall coalition's performance accounted for the latter effect. This study provided support for the hypothesis that perceived supernatural support can heighten both prospective confidence in coalitional victory and retrospective confidence in the combat performance of one's team, while highlighting the role of competitive play in evoking the coalitional psychology of intergroup conflict. These results accord with and extend convergent prior findings derived from laboratory paradigms far removed from the experience of combat. Accordingly, the field study approach utilized here shows promise as a method for investigating coalitional battle dynamics in a realistic, experientially immersive manner.

Diverse convergent evidence in the genetic analysis of complex disease: coordinating omic, informatic, and experimental evidence to better identify and validate risk factors

PubMed Central

2014-01-01

In omic research, such as genome wide association studies, researchers seek to repeat their results in other datasets to reduce false positive findings and thus provide evidence for the existence of true associations. Unfortunately this standard validation approach cannot completely eliminate false positive conclusions, and it can also mask many true associations that might otherwise advance our understanding of pathology. These issues beg the question: How can we increase the amount of knowledge gained from high throughput genetic data? To address this challenge, we present an approach that complements standard statistical validation methods by drawing attention to both potential false negative and false positive conclusions, as well as providing broad information for directing future research. The Diverse Convergent Evidence approach (DiCE) we propose integrates information from multiple sources (omics, informatics, and laboratory experiments) to estimate the strength of the available corroborating evidence supporting a given association. This process is designed to yield an evidence metric that has utility when etiologic heterogeneity, variable risk factor frequencies, and a variety of observational data imperfections might lead to false conclusions. We provide proof of principle examples in which DiCE identified strong evidence for associations that have established biological importance, when standard validation methods alone did not provide support. If used as an adjunct to standard validation methods this approach can leverage multiple distinct data types to improve genetic risk factor discovery/validation, promote effective science communication, and guide future research directions. PMID:25071867

Experimental evidence on microwave induced electron losses from ECRIS plasma

NASA Astrophysics Data System (ADS)

Sakildien, M.; Tarvainen, O.; Kronholm, R.; Izotov, I.; Skalyga, V.; Kalvas, T.; Jones, P.; Koivisto, H.

2018-06-01

The balance between warm and hot (>1 keV) electron density and their losses from the magnetic confinement system of an Electron Cyclotron Resonance Ion Source (ECRIS) plasma is considered to be one of the main factors determining the rate of the high charge state ion production. One of the key loss channels for heated electrons is thought to be induced by the injected microwaves. While this loss mechanism, referred to as rf-induced pitch angle scattering, has been studied theoretically and with computational tools, direct experimental evidence of its significance in minimum-B ECRIS plasmas remains limited. In this work, experimental evidence of microwave induced electron losses in the axial direction is presented in both continuous wave (CW) and pulsed operation of a 14 GHz ECRIS. In the CW mode, the experiment was carried out by comparing the characteristic X-ray emission from the plasma volume and from the surface of the biased disc located in the flux of the escaping electron at the axial magnetic mirror. Parametric sweeps of magnetic field, neutral gas pressure, and microwave power were conducted to determine their effect on electron losses. In the pulsed mode, the experiment was conducted by measuring the flux of escaping electrons through aluminum foils of different thicknesses providing some energy resolution. Both diagnostics support the view that rf-induced losses account for up to 70% of total hot electron losses and their importance depends on the source parameters, especially power and neutral gas pressure.

High-dose chemotherapy with autologous hematopoietic stem cell support for solid tumors in adults.

PubMed

Pedrazzoli, Paolo; Rosti, Giovanni; Secondino, Simona; Carminati, Ornella; Demirer, Taner

2007-10-01

Supported by experimental evidence and convincing results of early phase II studies, since the 1980s high-dose chemotherapy (HDC) with autologous hematopoietic stem cell support (AHSCT) has been uncritically adopted by many oncologists as a potentially curative option for several solid tumors. As a result, the number (and size) of randomized trials comparing this approach with conventional chemotherapy initiated (and often abandoned before completion) in this setting was limited and the benefit of a greater escalation of dose of chemotherapy with stem cell transplantation in solid tumors remains, with the possible exception of breast carcinoma (BC) and germ cell tumors (GCT), largely unsettled. In this article, we review and comment on the data from studies to date of HDC for solid tumors in adults.

Are Associations Between "Sexist" Video Games and Decreased Empathy Toward Women Robust? A Reanalysis of Gabbiadini et al. 2016.

PubMed

Ferguson, Christopher J; Donnellan, M Brent

2017-12-01

Gabbiadini, A., Riva, P., Andrighetto, L., Volpato, C., & Bushman, B, (PloS ONE, 2016) provided evidence for a connection between "sexist" video games and decreased empathy toward girls using an experimental paradigm. These claims are based on a moderated mediation model. They reported a three-way interaction between game condition, gender, and avatar identification when predicting masculine ideology in their original study. Masculine ideology was associated, in turn, with decreased empathy. However, there were no main experimental effects for video game condition on empathy. The current analysis considers the strength of the evidence for claims made in the original study on a sample of 153 adolescents (M age  = 16.812, SD = 1.241; 44.2% male). We confirmed that there was little evidence for an overall effect of game condition on empathy toward girls or women. We tested the robustness of the original reported moderated mediation models against other, theoretically derived alternatives, and found that effects differed based on how variables were measured (using alternatives in their public data file) and the statistical model used. The experimental groups differed significantly and substantially in terms of age suggesting that there might have been issues with the procedures used to randomly assign participants to conditions. These results highlight the need for preregistration of experimental protocols in video game research and raise some concerns about how moderated mediation models are used to support causal inferences. These results call into question whether use of "sexist" video games is a causal factor in the development of reduced empathy toward girls and women among adolescents.

Report on carcinogens monograph on cumene.

PubMed

2013-09-01

The National Toxicology Program conducted a cancer evaluation on cumene for possible listing in the Report on Carcinogens (RoC). The cancer evaluation is captured in the RoC monograph, which was peer reviewed in a public forum. The monograph consists of two components: (Part 1) the cancer evaluation, which reviews the relevant scientific information, assesses its quality, applies the RoC listing criteria to the scientific information, and provides the NTP recommendation for listing status for cumene in the RoC, and (Part 2) the substance profile proposed for the RoC, containing the NTP's listing status recommendation, a summary of the scientific evidence considered key to reaching that decision, and data on properties, use, production, exposure, and Federal regulations and guidelines to reduce exposure to cumene. This monograph provides an assessment of the available scientific information on cumene, including human exposure and properties, disposition and toxicokinetics, cancer studies in experimental animals, and studies of mechanisms and other related effects, including relevant toxicological effects, genetic toxicology, and mechanisms of carcinogenicity. From this assessment, the NTP recommended that cumene be listed as reasonably anticipated to be a human carcinogen in the RoC based on sufficient evidence from studies in experimental animals, which found that cumene exposure caused lung tumors in male and female mice and liver tumors in female mice. Several proposed mechanisms of carcinogenesis support the relevance to humans of the lung and liver tumors observed in experimental animals. Specifically, there is evidence that humans and experimental animals metabolize cumene through similar metabolic pathways. In addition, mutations of the K-ras oncogene and p53 tumor-suppressor gene observed in cumene-induced lung tumors in mice, along with altered expression of many other genes, resemble molecular alterations found in human lung and other cancers.

Middle school students' learning of mechanics concepts through engagement in different sequences of physical and virtual experiments

NASA Astrophysics Data System (ADS)

Sullivan, Sarah; Gnesdilow, Dana; Puntambekar, Sadhana; Kim, Jee-Seon

2017-08-01

Physical and virtual experimentation are thought to have different affordances for supporting students' learning. Research investigating the use of physical and virtual experiments to support students' learning has identified a variety of, sometimes conflicting, outcomes. Unanswered questions remain about how physical and virtual experiments may impact students' learning and for which contexts and content areas they may be most effective. Using a quasi-experimental design, we examined eighth grade students' (N = 100) learning of physics concepts related to pulleys depending on the sequence of physical and virtual labs they engaged in. Five classes of students were assigned to either the: physical first condition (PF) (n = 55), where students performed a physical pulley experiment and then performed the same experiment virtually, or virtual first condition (VF) (n = 45), with the opposite sequence. Repeated measures ANOVA's were conducted to examine how physical and virtual labs impacted students' learning of specific physics concepts. While we did not find clear-cut support that one sequence was better, we did find evidence that participating in virtual experiments may be more beneficial for learning certain physics concepts, such as work and mechanical advantage. Our findings support the idea that if time or physical materials are limited, using virtual experiments may help students understand work and mechanical advantage.

Transforming Big Data into cancer-relevant insight: An initial, multi-tier approach to assess reproducibility and relevance* | Office of Cancer Genomics

Cancer.gov

The Cancer Target Discovery and Development (CTD^2) Network was established to accelerate the transformation of "Big Data" into novel pharmacological targets, lead compounds, and biomarkers for rapid translation into improved patient outcomes. It rapidly became clear in this collaborative network that a key central issue was to define what constitutes sufficient computational or experimental evidence to support a biologically or clinically relevant finding.

Kinetic Evidence of an Apparent Negative Activation Enthalpy in an Organocatalytic Process

PubMed Central

Han, Xiao; Lee, Richmond; Chen, Tao; Luo, Jie; Lu, Yixin; Huang, Kuo-Wei

2013-01-01

A combined kinetic and computational study on our tryptophan-based bifunctional thiourea catalyzed asymmetric Mannich reactions reveals an apparent negative activation enthalpy. The formation of the pre-transition state complex has been unambiguously confirmed and these observations provide an experimental support for the formation of multiple hydrogen bonding network between the substrates and the catalyst. Such interactions allow the creation of a binding cavity, a key factor to install high enantioselectivity. PMID:23990028

Paternal leakage of mitochondrial DNA in experimental crosses of populations of the potato cyst nematode Globodera pallida.

PubMed

Hoolahan, Angelique H; Blok, Vivian C; Gibson, Tracey; Dowton, Mark

2011-12-01

Animal mtDNA is typically assumed to be maternally inherited. Paternal mtDNA has been shown to be excluded from entering the egg or eliminated post-fertilization in several animals. However, in the contact zones of hybridizing species and populations, the reproductive barriers between hybridizing organisms may not be as efficient at preventing paternal mtDNA inheritance, resulting in paternal leakage. We assessed paternal mtDNA leakage in experimental crosses of populations of a cyst-forming nematode, Globodera pallida. A UK population, Lindley, was crossed with two South American populations, P5A and P4A. Hybridization of these populations was supported by evidence of nuclear DNA from both the maternal and paternal populations in the progeny. To assess paternal mtDNA leakage, a ~3.4 kb non-coding mtDNA region was analyzed in the parental populations and in the progeny. Paternal mtDNA was evident in the progeny of both crosses involving populations P5A and P4A. Further, paternal mtDNA replaced the maternal mtDNA in 22 and 40 % of the hybrid cysts from these crosses, respectively. These results indicate that under appropriate conditions, paternal leakage occurs in the mtDNA of parasitic nematodes, and supports the hypothesis that hybrid zones facilitate paternal leakage. Thus, assumptions of strictly maternal mtDNA inheritance may be frequently violated, particularly when divergent populations interbreed.

Review article: do exercise and fitness protect against stress-induced health complaints? A review of the literature.

PubMed

Gerber, Markus; Pühse, Uwe

2009-11-01

Understanding how exercise influences health is important in designing public health interventions. At present, evidence suggests that there is a positive relationship between exercise and health. However, whether this relationship is partly due to the stress-moderating impact of exercise has been less frequently investigated although more and more people are taxed by stressful life circumstances. A comprehensive review of studies testing the potential of exercise as a stress-buffer was conducted (including literature from 1982 to 2008). The findings are based on a narrative review method. Specific criteria were taken into account to evaluate causality of the evidence. About half of the studies reported at least partly supportive results in the sense that people with high exercise levels exhibit less health problems when they encounter stress. The causality analyses show that stress-moderation effects were consistently found in different samples and with different methodological approaches. Although more support results from cross-sectional studies, exercise-based stress-buffer effects were also found in prospective, longitudinal and quasi-experimental investigations. This review underscores the relevance of exercise as a public health resource. Recommendations are provided for future research. More prospective and experimental studies are needed to provide insight into how much exercise is necessary to trigger stress-buffer effects. Furthermore, more information is warranted to conclude which sort of exercise has the strongest impact on the stress-illness-relationship.

Sex uncovered special issue: The ecology of sexual reproduction

PubMed Central

LIVELY, C. M.; MORRAN, L. T.

2014-01-01

Sexual reproduction is widely regarded as one of the major unexplained phenomena in biology. Nonetheless, while a general answer may remain elusive, considerable progress has been made in the last few decades. Here we fist review the genesis of, and support for, the major ecological hypotheses for biparental sexual reproduction. We then focus on the idea that host-parasite coevolution can favor cross fertilization over uniparental forms of reproduction, as this hypothesis currently has the most support from natural populations. We also review the results from experimental evolution studies, which tend to show that exposure to novel environments can select for higher levels of sexual reproduction, but that sex decreases in frequency after populations become adapted to the previously novel conditions. In contrast, experimental coevolution studies suggest that host-parasite interactions can lead to the long-term persistence of sex. Taken together, the evidence from natural populations and from laboratory experiments point to antagonistic coevolution as a potent and possibly ubiquitous force of selection favoring cross-fertilization and recombination. PMID:24617324

Myceliophthora thermophila syn. Sporotrichum thermophile: a thermophilic mould of biotechnological potential.

PubMed

Singh, Bijender

2016-01-01

Myceliophthora thermophila syn. Sporotrichum thermophile is a ubiquitous thermophilic mould with a strong ability to degrade organic matter during optimal growth at 45 °C. Both genome analysis and experimental data have suggested that the mould is capable of hydrolyzing all major polysaccharides found in biomass. The mould is able to secrete a large number of hydrolytic enzymes (cellulases, laccases, xylanases, pectinases, lipases, phytases and some other miscellaneous enzymes) employed in various biotechnological applications. Characterization of the biomass-hydrolyzing activity of wild and recombinant enzymes suggests that this mould is highly efficient in biomass decomposition at both moderate and high temperatures. The native enzymes produced by the mould are more efficient in activity than their mesophilic counterparts beside their low enzyme titers. The mould is able to synthesize various biomolecules, which are used in multifarious applications. Genome sequence data of M. thermophila also supported the physiological data. This review describes the biotechnological potential of thermophilic mould, M. thermophila supported by genomic and experimental evidences.

Evidence Combination From an Evolutionary Game Theory Perspective.

PubMed

Deng, Xinyang; Han, Deqiang; Dezert, Jean; Deng, Yong; Shyr, Yu

2016-09-01

Dempster-Shafer evidence theory is a primary methodology for multisource information fusion because it is good at dealing with uncertain information. This theory provides a Dempster's rule of combination to synthesize multiple evidences from various information sources. However, in some cases, counter-intuitive results may be obtained based on that combination rule. Numerous new or improved methods have been proposed to suppress these counter-intuitive results based on perspectives, such as minimizing the information loss or deviation. Inspired by evolutionary game theory, this paper considers a biological and evolutionary perspective to study the combination of evidences. An evolutionary combination rule (ECR) is proposed to help find the most biologically supported proposition in a multievidence system. Within the proposed ECR, we develop a Jaccard matrix game to formalize the interaction between propositions in evidences, and utilize the replicator dynamics to mimick the evolution of propositions. Experimental results show that the proposed ECR can effectively suppress the counter-intuitive behaviors appeared in typical paradoxes of evidence theory, compared with many existing methods. Properties of the ECR, such as solution's stability and convergence, have been mathematically proved as well.

Assessing the impact of mHealth interventions in low- and middle-income countries--what has been shown to work?

PubMed

Hall, Charles S; Fottrell, Edward; Wilkinson, Sophia; Byass, Peter

2014-01-01

Low-cost mobile devices, such as mobile phones, tablets, and personal digital assistants, which can access voice and data services, have revolutionised access to information and communication technology worldwide. These devices have a major impact on many aspects of people's lives, from business and education to health. This paper reviews the current evidence on the specific impacts of mobile technologies on tangible health outcomes (mHealth) in low- and middle-income countries (LMICs), from the perspectives of various stakeholders. Comprehensive literature searches were undertaken using key medical subject heading search terms on PubMed, Google Scholar, and grey literature sources. Analysis of 676 publications retrieved from the search was undertaken based on key inclusion criteria, resulting in a set of 76 papers for detailed review. The impacts of mHealth interventions reported in these papers were categorised into common mHealth applications. There is a growing evidence base for the efficacy of mHealth interventions in LMICs, particularly in improving treatment adherence, appointment compliance, data gathering, and developing support networks for health workers. However, the quantity and quality of the evidence is still limited in many respects. Over all application areas, there remains a need to take small pilot studies to full scale, enabling more rigorous experimental and quasi-experimental studies to be undertaken in order to strengthen the evidence base.

Urban green spaces' effectiveness as a psychological buffer for the negative health impact of noise pollution: a systematic review.

PubMed

Dzhambov, Angel Mario; Dimitrova, Donka Dimitrova

2014-01-01

Noise pollution is one of the four major pollutions in the world. Little evidence exists about the actual preventive benefits of psychological noise attenuation by urban green spaces, especially from the perspective of environmental medicine and, to the best of our knowledge, there is not a systematic analysis on this topic. The aim of this review was to systematically evaluate whether there is conclusive scientific evidence for the effectiveness of urban green spaces as a psychological buffer for the negative impact of noise pollution on human health and to promote an evidence-based approach toward this still growing environmental hazard. MEDLINE and EMBASE databases were searched for experimental and epidemiological studies published before June 04, 2013 in English and Spanish. Data was independently extracted in two step process by the authors. Due to the heterogeneity of the included studies qualitative assessment was performed. We found moderate evidence that the presence of vegetation can generally reduce the negative perception of noise (supported with an electroencephalogram test in one of the experimental studies; consistent with the data from two epidemiological studies; one experiment found no effect and one was inconclusive about the positive effect). This review fills a gap in the literature and could help researchers further clarify the proper implementation of urban green spaces as a psychological buffer in areas with population exposed to chronic noise pollution.

Assessing the impact of mHealth interventions in low- and middle-income countries – what has been shown to work?

PubMed Central

Hall, Charles S.; Fottrell, Edward; Wilkinson, Sophia; Byass, Peter

2014-01-01

Background Low-cost mobile devices, such as mobile phones, tablets, and personal digital assistants, which can access voice and data services, have revolutionised access to information and communication technology worldwide. These devices have a major impact on many aspects of people's lives, from business and education to health. This paper reviews the current evidence on the specific impacts of mobile technologies on tangible health outcomes (mHealth) in low- and middle-income countries (LMICs), from the perspectives of various stakeholders. Design Comprehensive literature searches were undertaken using key medical subject heading search terms on PubMed, Google Scholar, and grey literature sources. Analysis of 676 publications retrieved from the search was undertaken based on key inclusion criteria, resulting in a set of 76 papers for detailed review. The impacts of mHealth interventions reported in these papers were categorised into common mHealth applications. Results There is a growing evidence base for the efficacy of mHealth interventions in LMICs, particularly in improving treatment adherence, appointment compliance, data gathering, and developing support networks for health workers. However, the quantity and quality of the evidence is still limited in many respects. Conclusions Over all application areas, there remains a need to take small pilot studies to full scale, enabling more rigorous experimental and quasi-experimental studies to be undertaken in order to strengthen the evidence base. PMID:25361730

The Effect of Novel Research Activities on Long-term Survival of Temporarily Captive Steller Sea Lions (Eumetopias jubatus)

PubMed Central

Shuert, Courtney; Horning, Markus; Mellish, Jo-Ann

2015-01-01

Two novel research approaches were developed to facilitate controlled access to, and long-term monitoring of, juvenile Steller sea lions for periods longer than typically afforded by traditional fieldwork. The Transient Juvenile Steller sea lion Project at the Alaska SeaLife Center facilitated nutritional, physiological, and behavioral studies on the platform of temporary captivity. Temporarily captive sea lions (TJs, n = 35) were studied, and were intraperitoneally implanted with Life History Transmitters (LHX tags) to determine causes of mortality post-release. Our goal was to evaluate the potential for long-term impacts of temporary captivity and telemetry implants on the survival of study individuals. A simple open-population Cormack-Jolly-Seber mark-recapture model was built in program MARK, incorporating resightings of uniquely branded study individuals gathered by several contributing institutions. A priori models were developed to weigh the evidence of effects of experimental treatment on survival with covariates of sex, age, capture age, cohort, and age class. We compared survival of experimental treatment to a control group of n = 27 free-ranging animals (FRs) that were sampled during capture events and immediately released. Sex has previously been show to differentially affect juvenile survival in Steller sea lions. Therefore, sex was included in all models to account for unbalanced sex ratios within the experimental group. Considerable support was identified for the effects of sex, accounting for over 71% of total weight for all a priori models with delta AICc <5, and over 91% of model weight after removal of pretending variables. Overall, most support was found for the most parsimonious model based on sex and excluding experimental treatment. Models including experimental treatment were not supported after post-hoc considerations of model selection criteria. However, given the limited sample size, alternate models including effects of experimental treatments remain possible and effects may yet become apparent in larger sample sizes. PMID:26580549

Effects of a peer support programme for youth social services employees experiencing potentially traumatic events: a protocol for a prospective cohort study.

PubMed

Guay, Stephane; Tremblay, Nicole; Goncalves, Jane; Bilodeau, Henriette; Geoffrion, Steve

2017-06-24

The use of peer support programmes to help workers experiencing potentially traumatic events (PTE) has increased in high-risk organisations in the last decades. However, the scientific evidence of its effectiveness is still very limited. This paper aims to describe the protocol of a prospective cohort study that assesses the efficacy of a peer support programme among youth social services employees exposed to a PTE at work on psychological well-being, work functioning and needs of support. This is a mixed-methods prospective study that will examine workers' evolution four times over a 12-month period in Canada. This study involves: (1) quantitative data obtained through self-administrated questionnaires among 222 workers, and (2) qualitative in-depth interviews with a subsample of 45 workers. This study will compare findings from a cohort who received the support of a peer following a PTE (peer support-experimental protocol) as part of the experimental protocol of the Montreal Youth Social Services-University Institute (MYSS-UI), the second group of workers did not ask for the peer support (no peer support-experimental protocol) but was part of MYSS-UI, and the third group received standard organisational support from the Monteregie Youth Social Services (MYSS) (standard organisational protocol). The protocol and informed consent form complied with the ethics guidelines of the MYSS-UI. The Research Ethics Board of MYSS-UI and MYSS reviewed and accepted the protocol as required. The results of the study will be published in peer-reviewed journals, presented at research and general public conferences, disseminated via a public report for the institute that funded the project and for all workers. Results of this study will influence decision making regarding intervention policies following PTE and peer support interventions may be expanded throughout the youth social services in Canada and worldwide. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

Wiki Laboratory Notebooks: Supporting Student Learning in Collaborative Inquiry-Based Laboratory Experiments

NASA Astrophysics Data System (ADS)

Lawrie, Gwendolyn Angela; Grøndahl, Lisbeth; Boman, Simon; Andrews, Trish

2016-06-01

Recent examples of high-impact teaching practices in the undergraduate chemistry laboratory that include course-based undergraduate research experiences and inquiry-based experiments require new approaches to assessing individual student learning outcomes. Instructors require tools and strategies that can provide them with insight into individual student contributions to collaborative group/teamwork throughout the processes of experimental design, data analysis, display and communication of their outcomes in relation to their research question(s). Traditional assessments in the form of laboratory notebooks or experimental reports provide limited insight into the processes of collaborative inquiry-based activities. A wiki environment offers a collaborative domain that can potentially support collaborative laboratory processes and scientific record keeping. In this study, the effectiveness of the wiki in supporting laboratory learning and assessment has been evaluated through analysis of the content and histories for three consenting, participating groups of students. The conversational framework has been applied to map the relationships between the instructor, tutor, students and laboratory activities. Analytics that have been applied to the wiki platform include: character counts, page views, edits, timelines and the extent and nature of the contribution by each student to the wiki. Student perceptions of both the role and the impact of the wiki on their experiences and processes have also been collected. Evidence has emerged from this study that the wiki environment has enhanced co-construction of understanding of both the experimental process and subsequent communication of outcomes and data. A number of features are identified to support success in the use of the wiki platform for laboratory notebooks.

Plasmapheresis in thrombotic microangiopathy-associated syndromes: review of outcome data derived from clinical trials and open studies.

PubMed

von Baeyer, Hans

2002-08-01

Current reimbursement policy of health insurance for therapeutic plasmapheresis requires proof of efficacy using the concept of evidence-based medicine. The aim of this paper is to review the outcome of plasmapheresis used to treat thrombotic microangiopathy (TMA)-associated syndromes in the last decade to provide scientific evidence to back up reimbursement applications. The strength of evidence of each reviewed study was assessed using the five levels of evidence criteria as defined by the American Society of Hematology in 1996 for assessment of the treatment of immune thrombocytopenia. The level Experimental indication was added for situations where only case reports or small series supported by pathophysiological reasoning are available. The definitions of evidence used in this paper are as follows: Level I, randomized clinical trial with low rates of error (p < 0.01); Level II, randomized clinical trial with high rates of error (p < 0.05); Level III, nonrandomized studies with concurrent control group; Level IV, nonrandomized studies with historical control group; Level V, case series without a control group or expert opinion; and Experimental, case reports and pathophysiological reasoning. The results of this analysis based on the published data is summarized as follows: The indication of plasmapheresis is assigned to Level IV evidence for thrombotic thrombocytopenic purpura/hemolytic uremic syndrome (TTP/HUS); cancer/chemotherapy-associated TTP/HUS is assigned to Level V evidence; and TTP/HUS refractory to standard plasma exchange and post-bone marrow transplantation TTP/HUS are assigned to Experimental indication. For both subsets, protein A immunoadsorption is reportedly successful. The other TMA-associated syndromes, hemolysis elevated liver enzymes low platelets and HUS in early childhood, are no indication of plasmapheresis. Two randomized clinical trials were performed in order to demonstrate the superiority of plasma exchange/fresh frozen plasma (PEX/FFP) over plasma transfusion in the management of TTP/HUS. The results prove the greater clinical success of the latter type of plasma administration. Standard PEX/FFP has reduced the mortality of TTP/HUS from 94.5% to 13%.

The Brain Basis of Positive and Negative Affect: Evidence from a Meta-Analysis of the Human Neuroimaging Literature.

PubMed

Lindquist, Kristen A; Satpute, Ajay B; Wager, Tor D; Weber, Jochen; Barrett, Lisa Feldman

2016-05-01

The ability to experience pleasant or unpleasant feelings or to represent objects as "positive" or "negative" is known as representing hedonic "valence." Although scientists overwhelmingly agree that valence is a basic psychological phenomenon, debate continues about how to best conceptualize it scientifically. We used a meta-analysis of 397 functional magnetic resonance imaging (fMRI) and positron emission tomography studies (containing 914 experimental contrasts and 6827 participants) to test 3 competing hypotheses about the brain basis of valence: the bipolarity hypothesis that positive and negative affect are supported by a brain system that monotonically increases and/or decreases along the valence dimension, the bivalent hypothesis that positive and negative affect are supported by independent brain systems, and the affective workspace hypothesis that positive and negative affect are supported by a flexible set of valence-general regions. We found little evidence for the bipolar or bivalent hypotheses. Findings instead supported the hypothesis that, at the level of brain activity measurable by fMRI, valence is flexibly implemented across instances by a set of valence-general limbic and paralimbic brain regions. © The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

Keeping adolescent orphans in school to prevent human immunodeficiency virus infection: evidence from a randomized controlled trial in Kenya.

PubMed

Cho, Hyunsan; Hallfors, Denise D; Mbai, Isabella I; Itindi, Janet; Milimo, Benson W; Halpern, Carolyn T; Iritani, Bonita J

2011-05-01

We report the findings from a pilot study in western Kenya, using an experimental design to test whether comprehensive support used to keep adolescent orphans in school can reduce risk factors associated with infection with human immunodeficiency virus. Adolescent orphans aged 12-14 years (N = 105) in Nyanza Province were randomized to condition, after stratifying by household, gender, and baseline survey report of sexual behavior. The intervention comprised school fees, uniforms, and a "community visitor" who monitored school attendance and helped to resolve problems that would lead to absence or dropout. Data were analyzed using generalized estimating equations over two time points, controlling for gender and age. Compared with the control group, intervention students were less likely to drop out of school, commence sexual intercourse, or report attitudes supporting early sex. School support also increased prosocial bonding and gender equity attitudes. After 1 year of exposure to the intervention, we found evidence suggesting that comprehensive school support can prevent school dropout, delay sexual debut, and reduce risk factors associated with infection with human immunodeficiency virus. Further research, with much larger samples, is needed to better understand factors that mediate the association between educational support and delayed sexual debut, and how gender might moderate these relationships. Copyright © 2011 Society for Adolescent Health and Medicine. Published by Elsevier Inc. All rights reserved.

Nonpharmacologic Interventions to Prevent Pressure Ulcers in Older Patients: An Overview of Systematic Reviews (The Software ENgine for the Assessment and optimization of drug and non-drug Therapy in Older peRsons [SENATOR] Definition of Optimal Evidence-Based Non-drug Therapies in Older People [ONTOP] Series).

PubMed

Lozano-Montoya, Isabel; Vélez-Díaz-Pallarés, Manuel; Abraha, Iosief; Cherubini, Antonio; Soiza, Roy L; O'Mahony, Denis; Montero-Errasquín, Beatriz; Correa-Pérez, Andrea; Cruz-Jentoft, Alfonso J

2016-04-01

Pressure ulcers (PUs) are frequent in older patients, and the healing process is usually challenging, therefore, prevention should be the first strategic line in PU management. Nonpharmacologic interventions may play a role in the prevention of PUs in older people, but most systematic reviews (SRs) have not addressed this specific population using convincing outcome measures. To summarize and critically appraise the evidence from SRs of the primary studies on nonpharmacologic interventions to prevent PUs in older patients. SR and meta-analysis of comparative studies. PubMed, Cochrane Database of Systematic Reviews, EMBASE, and CINHAL (from inception to October 2013) were searched. A new search for updates in the Cochrane Database was launched in July 2014. SRs that included at least 1 comparative study evaluating any nonpharmacologic intervention to prevent PUs in older patients, in any healthcare setting, were selected. Any primary study with experimental design was then identified and included. From each primary study, quality assessment was undertaken as specified by the Cochrane Collaboration and the Grading of Recommendations Assessment, Development and Evaluation working group. Interventions were identified and compared among different studies to explore the possibility of performing a meta-analysis, using the incidence of new pressure ulcers as the main outcome measure. One hundred ten SRs with 65 primary studies satisfied the inclusion criteria. The most frequent interventions explored in these trials were support surfaces (41 studies), repositioning (8), and nutrition interventions (5). High quality of evidence was not found for any intervention, mainly because of a high risk of bias and imprecision. There is moderate quality evidence to support the use of alternating pressure support mattresses over usual hospital mattresses in medical and surgical inpatients, low quality evidence to support constant low pressure devices and Australian medical sheepskin over usual mattresses, and very low quality evidence to support nutrition interventions in hospital settings. No recommendations on hydration, repositioning, standardized risk assessment, or multicomponent interventions can be done. In older patients at high risk to suffer PUs, high-technology and low- technology support surfaces can significantly reduce the incidence of PUs. Nutrition intervention may also have a role in preventing PUs in hospital settings. More evidence is needed to support other recommendations, which is specially lacking for repositioning. Copyright © 2016 AMDA – The Society for Post-Acute and Long-Term Care Medicine. Published by Elsevier Inc. All rights reserved.

Robot education peers in a situated primary school study: Personalisation promotes child learning.

PubMed

Baxter, Paul; Ashurst, Emily; Read, Robin; Kennedy, James; Belpaeme, Tony

2017-01-01

The benefit of social robots to support child learning in an educational context over an extended period of time is evaluated. Specifically, the effect of personalisation and adaptation of robot social behaviour is assessed. Two autonomous robots were embedded within two matched classrooms of a primary school for a continuous two week period without experimenter supervision to act as learning companions for the children for familiar and novel subjects. Results suggest that while children in both personalised and non-personalised conditions learned, there was increased child learning of a novel subject exhibited when interacting with a robot that personalised its behaviours, with indications that this benefit extended to other class-based performance. Additional evidence was obtained suggesting that there is increased acceptance of the personalised robot peer over a non-personalised version. These results provide the first evidence in support of peer-robot behavioural personalisation having a positive influence on learning when embedded in a learning environment for an extended period of time.

Money giveth, money taketh away: the dual effect of wealth on happiness.

PubMed

Quoidbach, Jordi; Dunn, Elizabeth W; Petrides, K V; Mikolajczak, Moïra

2010-06-01

This study provides the first evidence that money impairs people's ability to savor everyday positive emotions and experiences. In a sample of working adults, wealthier individuals reported lower savoring ability (the ability to enhance and prolong positive emotional experience). Moreover, the negative impact of wealth on individuals' ability to savor undermined the positive effects of money on their happiness. We experimentally exposed participants to a reminder of wealth and produced the same deleterious effect on their ability to savor as that produced by actual individual differences in wealth, a result supporting the theory that money has a causal effect on savoring. Moving beyond self-reports, we found that participants exposed to a reminder of wealth spent less time savoring a piece of chocolate and exhibited reduced enjoyment of it compared with participants not exposed to wealth. This article presents evidence supporting the widely held but previously untested belief that having access to the best things in life may actually undercut people's ability to reap enjoyment from life's small pleasures.

Metagenomic identification of active methanogens and methanotrophs in serpentinite springs of the Voltri Massif, Italy

PubMed Central

Thornton, Christopher N.; Hyer, Alex; Twing, Katrina I.; Longino, August A.; Lang, Susan Q.; Lilley, Marvin D.; Früh-Green, Gretchen L.; Schrenk, Matthew O.

2017-01-01

The production of hydrogen and methane by geochemical reactions associated with the serpentinization of ultramafic rocks can potentially support subsurface microbial ecosystems independent of the photosynthetic biosphere. Methanogenic and methanotrophic microorganisms are abundant in marine hydrothermal systems heavily influenced by serpentinization, but evidence for methane-cycling archaea and bacteria in continental serpentinite springs has been limited. This report provides metagenomic and experimental evidence for active methanogenesis and methanotrophy by microbial communities in serpentinite springs of the Voltri Massif, Italy. Methanogens belonging to family Methanobacteriaceae and methanotrophic bacteria belonging to family Methylococcaceae were heavily enriched in three ultrabasic springs (pH 12). Metagenomic data also suggest the potential for hydrogen oxidation, hydrogen production, carbon fixation, fermentation, and organic acid metabolism in the ultrabasic springs. The predicted metabolic capabilities are consistent with an active subsurface ecosystem supported by energy and carbon liberated by geochemical reactions within the serpentinite rocks of the Voltri Massif. PMID:28149702

Robot education peers in a situated primary school study: Personalisation promotes child learning

PubMed Central

Ashurst, Emily; Read, Robin; Kennedy, James; Belpaeme, Tony

2017-01-01

The benefit of social robots to support child learning in an educational context over an extended period of time is evaluated. Specifically, the effect of personalisation and adaptation of robot social behaviour is assessed. Two autonomous robots were embedded within two matched classrooms of a primary school for a continuous two week period without experimenter supervision to act as learning companions for the children for familiar and novel subjects. Results suggest that while children in both personalised and non-personalised conditions learned, there was increased child learning of a novel subject exhibited when interacting with a robot that personalised its behaviours, with indications that this benefit extended to other class-based performance. Additional evidence was obtained suggesting that there is increased acceptance of the personalised robot peer over a non-personalised version. These results provide the first evidence in support of peer-robot behavioural personalisation having a positive influence on learning when embedded in a learning environment for an extended period of time. PMID:28542648

Experimental Evidence of the Tonic Vibration Reflex during Whole-Body Vibration of the Loaded and Unloaded Leg

PubMed Central

Zaidell, Lisa N.; Mileva, Katya N.; Sumners, David P.; Bowtell, Joanna L.

2013-01-01

Increased muscle activation during whole-body vibration (WBV) is mainly ascribed to a complex spinal and supraspinal neurophysiological mechanism termed the tonic vibration reflex (TVR). However, TVR has not been experimentally demonstrated during low-frequency WBV, therefore this investigation aimed to determine the expression of TVR during WBV.  Whilst seated, eight healthy males were exposed to either vertical WBV applied to the leg via the plantar-surface of the foot, or Achilles tendon vibration (ATV) at 25Hz and 50Hzfor 70s. Ankle plantar-flexion force, tri-axial accelerations at the shank and vibration source, and surface EMG activity of m. soleus (SOL) and m. tibialis anterior (TA) were recorded from the unloaded and passively loaded leg to simulate body mass supported during standing.  Plantar flexion force was similarly augmented by WBV and ATV and increased over time in a load- and frequency dependent fashion. SOL and TA EMG amplitudes increased over time in all conditions independently of vibration mode. 50Hz WBV and ATV resulted in greater muscle activation than 25Hz in SOL when the shank was loaded and in TA when the shank was unloaded despite the greater transmission of vertical acceleration from source to shank with 25Hz and WBV, especially during loading. Low-amplitude WBV of the unloaded and passively loaded leg produced slow tonic muscle contraction and plantar-flexion force increase of similar magnitudes to those induced by Achilles tendon vibration at the same frequencies. This study provides the first experimental evidence supporting the TVR as a plausible mechanism underlying the neuromuscular response to whole-body vibration. PMID:24386466

Evidence for contact calls in fish: conspecific vocalisations and ambient soundscape influence group cohesion in a nocturnal species.

PubMed

van Oosterom, L; Montgomery, J C; Jeffs, A G; Radford, C A

2016-01-11

Soundscapes provide a new tool for the study of fish communities. Bigeyes (Pempheris adspersa) are nocturnal planktivorous reef fish, feed in loose shoals and are soniferous. These vocalisations have been suggested to be contact calls to maintain group cohesion, however direct evidence for this is absent, despite the fact that contact calls are well documented for many other vertebrates, including marine mammals. For fish, direct evidence for group cohesion signals is restricted to the use of visual and hydrodynamic cues. In support of adding vocalisation as a contributing cue, our laboratory experiments show that bigeyes significantly increased group cohesion when exposed to recordings of ambient reef sound at higher sound levels while also decreasing vocalisations. These patterns of behaviour are consistent with acoustic masking. When exposed to playback of conspecific vocalisations, the group cohesion and vocalisation rates of bigeyes both significantly increased. These results provide the first direct experimental support for the hypotheses that vocalisations are used as contact calls to maintain group cohesion in fishes, making fish the evolutionarily oldest vertebrate group in which this phenomenon has been observed, and adding a new dimension to the interpretation of nocturnal reef soundscapes.

Evidence for contact calls in fish: conspecific vocalisations and ambient soundscape influence group cohesion in a nocturnal species

NASA Astrophysics Data System (ADS)

van Oosterom, L.; Montgomery, J. C.; Jeffs, A. G.; Radford, C. A.

2016-01-01

Soundscapes provide a new tool for the study of fish communities. Bigeyes (Pempheris adspersa) are nocturnal planktivorous reef fish, feed in loose shoals and are soniferous. These vocalisations have been suggested to be contact calls to maintain group cohesion, however direct evidence for this is absent, despite the fact that contact calls are well documented for many other vertebrates, including marine mammals. For fish, direct evidence for group cohesion signals is restricted to the use of visual and hydrodynamic cues. In support of adding vocalisation as a contributing cue, our laboratory experiments show that bigeyes significantly increased group cohesion when exposed to recordings of ambient reef sound at higher sound levels while also decreasing vocalisations. These patterns of behaviour are consistent with acoustic masking. When exposed to playback of conspecific vocalisations, the group cohesion and vocalisation rates of bigeyes both significantly increased. These results provide the first direct experimental support for the hypotheses that vocalisations are used as contact calls to maintain group cohesion in fishes, making fish the evolutionarily oldest vertebrate group in which this phenomenon has been observed, and adding a new dimension to the interpretation of nocturnal reef soundscapes.

Evidence for contact calls in fish: conspecific vocalisations and ambient soundscape influence group cohesion in a nocturnal species

PubMed Central

van Oosterom, L.; Montgomery, J. C.; Jeffs, A. G.; Radford, C. A.

2016-01-01

Soundscapes provide a new tool for the study of fish communities. Bigeyes (Pempheris adspersa) are nocturnal planktivorous reef fish, feed in loose shoals and are soniferous. These vocalisations have been suggested to be contact calls to maintain group cohesion, however direct evidence for this is absent, despite the fact that contact calls are well documented for many other vertebrates, including marine mammals. For fish, direct evidence for group cohesion signals is restricted to the use of visual and hydrodynamic cues. In support of adding vocalisation as a contributing cue, our laboratory experiments show that bigeyes significantly increased group cohesion when exposed to recordings of ambient reef sound at higher sound levels while also decreasing vocalisations. These patterns of behaviour are consistent with acoustic masking. When exposed to playback of conspecific vocalisations, the group cohesion and vocalisation rates of bigeyes both significantly increased. These results provide the first direct experimental support for the hypotheses that vocalisations are used as contact calls to maintain group cohesion in fishes, making fish the evolutionarily oldest vertebrate group in which this phenomenon has been observed, and adding a new dimension to the interpretation of nocturnal reef soundscapes. PMID:26750559

Pet ownership and cardiovascular risk reduction: supporting evidence, conflicting data and underlying mechanisms.

PubMed

Arhant-Sudhir, Kanish; Arhant-Sudhir, Rish; Sudhir, Krishnankutty

2011-11-01

1. It is widely believed that pet ownership is beneficial to humans and that some of this benefit is through favourable effects on cardiovascular risk. In the present review, we critically examine the evidence in support of this hypothesis and present the available data with respect to major cardiovascular risk factors. 2. There is evidence that dog owners are less sedentary and have lower blood pressure, plasma cholesterol and triglycerides, attenuated responses to laboratory-induced mental stress and improved survival following myocardial infarction compared with non-pet owners. However, conflicting data exist with regard to the association between pet ownership and each of these risk factors. 3. Numerous non-cardiovascular effects of pet ownership have been reported, largely in the psychosocial domain, but the relationship is complex and can vary with demographic and social factors. 4. A unifying hypothesis is presented, linking improved mood and emotional state to decreased central and regional autonomic activity, improved endothelial function and, thus, lower blood pressure and reduced cardiac arrhythmias. 5. Overall, ownership of domestic pets, particularly dogs, is associated with positive health benefits. © 2011 The Authors. Clinical and Experimental Pharmacology and Physiology © 2011 Blackwell Publishing Asia Pty Ltd.

The Role of Omics in the Application of Adverse Outcome Pathways for Chemical Risk Assessment.

PubMed

Brockmeier, Erica K; Hodges, Geoff; Hutchinson, Thomas H; Butler, Emma; Hecker, Markus; Tollefsen, Knut Erik; Garcia-Reyero, Natalia; Kille, Peter; Becker, Dörthe; Chipman, Kevin; Colbourne, John; Collette, Timothy W; Cossins, Andrew; Cronin, Mark; Graystock, Peter; Gutsell, Steve; Knapen, Dries; Katsiadaki, Ioanna; Lange, Anke; Marshall, Stuart; Owen, Stewart F; Perkins, Edward J; Plaistow, Stewart; Schroeder, Anthony; Taylor, Daisy; Viant, Mark; Ankley, Gerald; Falciani, Francesco

2017-08-01

In conjunction with the second International Environmental Omics Symposium (iEOS) conference, held at the University of Liverpool (United Kingdom) in September 2014, a workshop was held to bring together experts in toxicology and regulatory science from academia, government and industry. The purpose of the workshop was to review the specific roles that high-content omics datasets (eg, transcriptomics, metabolomics, lipidomics, and proteomics) can hold within the adverse outcome pathway (AOP) framework for supporting ecological and human health risk assessments. In light of the growing number of examples of the application of omics data in the context of ecological risk assessment, we considered how omics datasets might continue to support the AOP framework. In particular, the role of omics in identifying potential AOP molecular initiating events and providing supportive evidence of key events at different levels of biological organization and across taxonomic groups was discussed. Areas with potential for short and medium-term breakthroughs were also discussed, such as providing mechanistic evidence to support chemical read-across, providing weight of evidence information for mode of action assignment, understanding biological networks, and developing robust extrapolations of species-sensitivity. Key challenges that need to be addressed were considered, including the need for a cohesive approach towards experimental design, the lack of a mutually agreed framework to quantitatively link genes and pathways to key events, and the need for better interpretation of chemically induced changes at the molecular level. This article was developed to provide an overview of ecological risk assessment process and a perspective on how high content molecular-level datasets can support the future of assessment procedures through the AOP framework. © The Author 2017. Published by Oxford University Press on behalf of the Society of Toxicology.

The Role of Omics in the Application of Adverse Outcome Pathways for Chemical Risk Assessment

PubMed Central

Brockmeier, Erica K.; Hodges, Geoff; Hutchinson, Thomas H.; Butler, Emma; Hecker, Markus; Tollefsen, Knut Erik; Garcia-Reyero, Natalia; Kille, Peter; Becker, Dörthe; Chipman, Kevin; Colbourne, John; Collette, Timothy W.; Cossins, Andrew; Cronin, Mark; Graystock, Peter; Gutsell, Steve; Knapen, Dries; Katsiadaki, Ioanna; Lange, Anke; Marshall, Stuart; Owen, Stewart F.; Perkins, Edward J.; Plaistow, Stewart; Schroeder, Anthony; Taylor, Daisy; Viant, Mark; Ankley, Gerald; Falciani, Francesco

2017-01-01

Abstract In conjunction with the second International Environmental Omics Symposium (iEOS) conference, held at the University of Liverpool (United Kingdom) in September 2014, a workshop was held to bring together experts in toxicology and regulatory science from academia, government and industry. The purpose of the workshop was to review the specific roles that high-content omics datasets (eg, transcriptomics, metabolomics, lipidomics, and proteomics) can hold within the adverse outcome pathway (AOP) framework for supporting ecological and human health risk assessments. In light of the growing number of examples of the application of omics data in the context of ecological risk assessment, we considered how omics datasets might continue to support the AOP framework. In particular, the role of omics in identifying potential AOP molecular initiating events and providing supportive evidence of key events at different levels of biological organization and across taxonomic groups was discussed. Areas with potential for short and medium-term breakthroughs were also discussed, such as providing mechanistic evidence to support chemical read-across, providing weight of evidence information for mode of action assignment, understanding biological networks, and developing robust extrapolations of species-sensitivity. Key challenges that need to be addressed were considered, including the need for a cohesive approach towards experimental design, the lack of a mutually agreed framework to quantitatively link genes and pathways to key events, and the need for better interpretation of chemically induced changes at the molecular level. This article was developed to provide an overview of ecological risk assessment process and a perspective on how high content molecular-level datasets can support the future of assessment procedures through the AOP framework. PMID:28525648

Effectiveness of an Evidence-Based Practice Nurse Mentor Training Program.

PubMed

Spiva, LeeAnna; Hart, Patricia L; Patrick, Sara; Waggoner, Jessica; Jackson, Charon; Threatt, Jamie L

2017-06-01

Multiple reasons are cited for why nurses do not incorporate evidence into clinical practice, including lack of knowledge and skills, training, time, and organizational support. To investigate the effectiveness of a mentor training program on mentors' perceptions of knowledge, attitude, skill, and confidence levels, and organizational readiness related to evidence-based practice (EBP) and research utilization; and to investigate the effectiveness of creating a formalized structure to enculturate EBP in order to prepare nurses to incorporate EBP into clinical practice on nurses' perceptions of knowledge, attitude, skill levels, barriers, nursing leadership, and organizational support related to EBP and research utilization. A two-group pretest-posttest quasi-experimental, interventional design was used. A convenience sample of 66 mentors and 367 nurses working at a five hospital integrated healthcare system located in the Southeastern United States participated. Nurse mentors' knowledge, attitude, skill level, and organizational readiness related to EBP, t = -8.64, p < .001, and confidence, t = -6.36, p < .001, improved after training. Nurses' knowledge, attitude, and skill level related to EBP, t = -19.12, p < .001, and barriers to research utilization, t = 20.86, p < .001, EBP work environment t = -20.18, p < .001, and EBP nurse leadership, t = -16.50, p < .001, improved after a formalized structure was implemented. EBP mentors are effective in educating and supporting nurses in evidence-based care. Leaders should use a multifaceted approach to build and sustain EBP, including developing a critical mass of EBP mentors to work with point of care staff. © 2017 Sigma Theta Tau International.

Correctional nursing: a study protocol to develop an educational intervention to optimize nursing practice in a unique context.

PubMed

Almost, Joan; Gifford, Wendy A; Doran, Diane; Ogilvie, Linda; Miller, Crystal; Rose, Don N; Squires, Mae

2013-06-21

Nurses are the primary healthcare providers in correctional facilities. A solid knowledge and expertise that includes the use of research evidence in clinical decision making is needed to optimize nursing practice and promote positive health outcomes within these settings. The institutional emphasis on custodial care within a heavily secured, regulated, and punitive environment presents unique contextual challenges for nursing practice. Subsequently, correctional nurses are not always able to obtain training or ongoing education that is required for broad scopes of practice. The purpose of the proposed study is to develop an educational intervention for correctional nurses to support the provision of evidence-informed care. A two-phase mixed methods research design will be used. The setting will be three provincial correctional facilities. Phase one will focus on identifying nurses' scope of practice and practice needs, describing work environment characteristics that support evidence-informed practice and developing the intervention. Semi-structured interviews will be completed with nurses and nurse managers. To facilitate priorities for the intervention, a Delphi process will be used to rank the learning needs identified by participants. Based on findings, an online intervention will be developed. Phase two will involve evaluating the acceptability and feasibility of the intervention to inform a future experimental design. The context of provincial correctional facilities presents unique challenges for nurses' provision of care. This study will generate information to address practice and learning needs specific to correctional nurses. Interventions tailored to barriers and supports within specific contexts are important to enable nurses to provide evidence-informed care.

Immunology and Homeopathy. 3. Experimental Studies on Animal Models

PubMed Central

Bellavite, Paolo; Ortolani, Riccardo; Conforti, Anita

2006-01-01

A search of the literature and the experiments carried out by the authors of this review show that there are a number of animal models where the effect of homeopathic dilutions or the principles of homeopathic medicine have been tested. The results relate to the immunostimulation by ultralow doses of antigens, the immunological models of the ‘simile’, the regulation of acute or chronic inflammatory processes and the use of homeopathic medicines in farming. The models utilized by different research groups are extremely etherogeneous and differ as the test medicines, the dilutions and the outcomes are concerned. Some experimental lines, particularly those utilizing mice models of immunomodulation and anti-inflammatory effects of homeopathic complex formulations, give support to a real effect of homeopathic high dilutions in animals, but often these data are of preliminary nature and have not been independently replicated. The evidence emerging from animal models is supporting the traditional ‘simile’ rule, according to which ultralow doses of compounds, that in high doses are pathogenic, may have paradoxically a protective or curative effect. Despite a few encouraging observational studies, the effectiveness of the homeopathic prevention or therapy of infections in veterinary medicine is not sufficiently supported by randomized and controlled trials. PMID:16786046

mHealth for HIV Treatment & Prevention: A Systematic Review of the Literature

PubMed Central

Catalani, Caricia; Philbrick, William; Fraser, Hamish; Mechael, , Patricia; Israelski, Dennis M.

2013-01-01

This systematic review assesses the published literature to describe the landscape of mobile health technology (mHealth) for HIV/AIDS and the evidence supporting the use of these tools to address the HIV prevention, care, and treatment cascade. The speed of innovation, broad range of initiatives and tools, and heterogeneity in reporting have made it difficult to uncover and synthesize knowledge on how mHealth tools might be effective in addressing the HIV pandemic. To do address this gap, a team of reviewers collected literature on the use of mobile technology for HIV/AIDS among health, engineering, and social science literature databases and analyzed a final set of 62 articles. Articles were systematically coded, assessed for scientific rigor, and sorted for HIV programmatic relevance. The review revealed evidence that mHealth tools support HIV programmatic priorities, including: linkage to care, retention in care, and adherence to antiretroviral treatment. In terms of technical features, mHealth tools facilitate alerts and reminders, data collection, direct voice communication, educational messaging, information on demand, and more. Studies were mostly descriptive with a growing number of quasi-experimental and experimental designs. There was a lack of evidence around the use of mHealth tools to address the needs of key populations, including pregnant mothers, sex workers, users of injection drugs, and men who have sex with men. The science and practice of mHealth for HIV are evolving rapidly, but still in their early stages. Small-scale efforts, pilot projects, and preliminary descriptive studies are advancing and there is a promising trend toward implementing mHealth innovation that is feasible and acceptable within low-resource settings, positive program outcomes, operational improvements, and rigorous study design PMID:24133558

Natural selection promotes antigenic evolvability.

PubMed

Graves, Christopher J; Ros, Vera I D; Stevenson, Brian; Sniegowski, Paul D; Brisson, Dustin

2013-01-01

The hypothesis that evolvability - the capacity to evolve by natural selection - is itself the object of natural selection is highly intriguing but remains controversial due in large part to a paucity of direct experimental evidence. The antigenic variation mechanisms of microbial pathogens provide an experimentally tractable system to test whether natural selection has favored mechanisms that increase evolvability. Many antigenic variation systems consist of paralogous unexpressed 'cassettes' that recombine into an expression site to rapidly alter the expressed protein. Importantly, the magnitude of antigenic change is a function of the genetic diversity among the unexpressed cassettes. Thus, evidence that selection favors among-cassette diversity is direct evidence that natural selection promotes antigenic evolvability. We used the Lyme disease bacterium, Borrelia burgdorferi, as a model to test the prediction that natural selection favors amino acid diversity among unexpressed vls cassettes and thereby promotes evolvability in a primary surface antigen, VlsE. The hypothesis that diversity among vls cassettes is favored by natural selection was supported in each B. burgdorferi strain analyzed using both classical (dN/dS ratios) and Bayesian population genetic analyses of genetic sequence data. This hypothesis was also supported by the conservation of highly mutable tandem-repeat structures across B. burgdorferi strains despite a near complete absence of sequence conservation. Diversification among vls cassettes due to natural selection and mutable repeat structures promotes long-term antigenic evolvability of VlsE. These findings provide a direct demonstration that molecular mechanisms that enhance evolvability of surface antigens are an evolutionary adaptation. The molecular evolutionary processes identified here can serve as a model for the evolution of antigenic evolvability in many pathogens which utilize similar strategies to establish chronic infections.

Natural Selection Promotes Antigenic Evolvability

PubMed Central

Graves, Christopher J.; Ros, Vera I. D.; Stevenson, Brian; Sniegowski, Paul D.; Brisson, Dustin

2013-01-01

The hypothesis that evolvability - the capacity to evolve by natural selection - is itself the object of natural selection is highly intriguing but remains controversial due in large part to a paucity of direct experimental evidence. The antigenic variation mechanisms of microbial pathogens provide an experimentally tractable system to test whether natural selection has favored mechanisms that increase evolvability. Many antigenic variation systems consist of paralogous unexpressed ‘cassettes’ that recombine into an expression site to rapidly alter the expressed protein. Importantly, the magnitude of antigenic change is a function of the genetic diversity among the unexpressed cassettes. Thus, evidence that selection favors among-cassette diversity is direct evidence that natural selection promotes antigenic evolvability. We used the Lyme disease bacterium, Borrelia burgdorferi, as a model to test the prediction that natural selection favors amino acid diversity among unexpressed vls cassettes and thereby promotes evolvability in a primary surface antigen, VlsE. The hypothesis that diversity among vls cassettes is favored by natural selection was supported in each B. burgdorferi strain analyzed using both classical (dN/dS ratios) and Bayesian population genetic analyses of genetic sequence data. This hypothesis was also supported by the conservation of highly mutable tandem-repeat structures across B. burgdorferi strains despite a near complete absence of sequence conservation. Diversification among vls cassettes due to natural selection and mutable repeat structures promotes long-term antigenic evolvability of VlsE. These findings provide a direct demonstration that molecular mechanisms that enhance evolvability of surface antigens are an evolutionary adaptation. The molecular evolutionary processes identified here can serve as a model for the evolution of antigenic evolvability in many pathogens which utilize similar strategies to establish chronic infections. PMID:24244173

On the levels of enzymatic substrate specificity: Implications for the early evolution of metabolic pathways

NASA Technical Reports Server (NTRS)

Lazcano, A.; Diaz-Villagomez, E.; Mills, T.; Oro, J.

1995-01-01

The most frequently invoked explanation for the origin of metabolic pathways is the retrograde evolution hypothesis. In contrast, according to the so-called 'patchwork' theory, metabolism evolved by the recruitment of relatively inefficient small enzymes of broad specificity that could react with a wide range of chemically related substrates. In this paper it is argued that both sequence comparisons and experimental results on enzyme substrate specificity support the patchwork assembly theory. The available evidence supports previous suggestions that gene duplication events followed by a gradual neoDarwinian accumulation of mutations and other minute genetic changes lead to the narrowing and modification of enzyme function in at least some primordial metabolic pathways.

The role of astrocytic glycogen in supporting the energetics of neuronal activity.

PubMed

Dinuzzo, Mauro; Mangia, Silvia; Maraviglia, Bruno; Giove, Federico

2012-11-01

Energy homeostasis in the brain is maintained by oxidative metabolism of glucose, primarily to fulfil the energy demand associated with ionic movements in neurons and astrocytes. In this contribution we review the experimental evidence that grounds a specific role of glycogen metabolism in supporting the functional energetic needs of astrocytes during the removal of extracellular potassium. Based on theoretical considerations, we further discuss the hypothesis that the mobilization of glycogen in astrocytes serves the purpose to enhance the availability of glucose for neuronal glycolytic and oxidative metabolism at the onset of stimulation. Finally, we provide an evolutionary perspective for explaining the selection of glycogen as carbohydrate reserve in the energy-sensing machinery of cell metabolism.

Evidence-based cognitive rehabilitation: updated review of the literature from 2003 through 2008.

PubMed

Cicerone, Keith D; Langenbahn, Donna M; Braden, Cynthia; Malec, James F; Kalmar, Kathleen; Fraas, Michael; Felicetti, Thomas; Laatsch, Linda; Harley, J Preston; Bergquist, Thomas; Azulay, Joanne; Cantor, Joshua; Ashman, Teresa

2011-04-01

To update our clinical recommendations for cognitive rehabilitation of people with traumatic brain injury (TBI) and stroke, based on a systematic review of the literature from 2003 through 2008. PubMed and Infotrieve literature searches were conducted using the terms attention, awareness, cognitive, communication, executive, language, memory, perception, problem solving, and/or reasoning combined with each of the following terms: rehabilitation, remediation, and training for articles published between 2003 and 2008. The task force initially identified citations for 198 published articles. One hundred forty-one articles were selected for inclusion after our initial screening. Twenty-nine studies were excluded after further detailed review. Excluded articles included 4 descriptive studies without data, 6 nontreatment studies, 7 experimental manipulations, 6 reviews, 1 single case study not related to TBI or stroke, 2 articles where the intervention was provided to caretakers, 1 article redacted by the journal, and 2 reanalyses of prior publications. We fully reviewed and evaluated 112 studies. Articles were assigned to 1 of 6 categories reflecting the primary area of intervention: attention; vision and visuospatial functioning; language and communication skills; memory; executive functioning, problem solving and awareness; and comprehensive-holistic cognitive rehabilitation. Articles were abstracted and levels of evidence determined using specific criteria. Of the 112 studies, 14 were rated as class I, 5 as class Ia, 11 as class II, and 82 as class III. Evidence within each area of intervention was synthesized and recommendations for Practice Standards, Practice Guidelines, and Practice Options were made. There is substantial evidence to support interventions for attention, memory, social communication skills, executive function, and for comprehensive-holistic neuropsychologic rehabilitation after TBI. Evidence supports visuospatial rehabilitation after right hemisphere stroke, and interventions for aphasia and apraxia after left hemisphere stroke. Together with our prior reviews, we have evaluated a total of 370 interventions, including 65 class I or Ia studies. There is now sufficient information to support evidence-based protocols and implement empirically-supported treatments for cognitive disability after TBI and stroke. Copyright © 2011 American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.

Physical Justification for Negative Remanent Magnetization in Homogeneous Nanoparticles

PubMed Central

Gu, Shuo; He, Weidong; Zhang, Ming; Zhuang, Taisen; Jin, Yi; ElBidweihy, Hatem; Mao, Yiwu; Dickerson, James H.; Wagner, Michael J.; Torre, Edward Della; Bennett, Lawrence H.

2014-01-01

The phenomenon of negative remanent magnetization (NRM) has been observed experimentally in a number of heterogeneous magnetic systems and has been considered anomalous. The existence of NRM in homogenous magnetic materials is still in debate, mainly due to the lack of compelling support from experimental data and a convincing theoretical explanation for its thermodynamic validation. Here we resolve the long-existing controversy by presenting experimental evidence and physical justification that NRM is real in a prototype homogeneous ferromagnetic nanoparticle, an europium sulfide nanoparticle. We provide novel insights into major and minor hysteresis behavior that illuminate the true nature of the observed inverted hysteresis and validate its thermodynamic permissibility and, for the first time, present counterintuitive magnetic aftereffect behavior that is consistent with the mechanism of magnetization reversal, possessing unique capability to identify NRM. The origin and conditions of NRM are explained quantitatively via a wasp-waist model, in combination of energy calculations. PMID:25183061

Detection of Classical swine fever virus infection by individual oral fluid of pigs following experimental inoculation.

PubMed

Petrini, Stefano; Pierini, Ilaria; Giammarioli, Monica; Feliziani, Francesco; De Mia, Gian Mario

2017-03-01

We evaluated the use of oral fluid as an alternative to serum samples for Classical swine fever virus (CSFV) detection. Individual oral fluid and serum samples were collected at different times post-infection from pigs that were experimentally inoculated with CSFV Alfort 187 strain. We found no evidence of CSFV neutralizing antibodies in swine oral fluid samples under our experimental conditions. In contrast, real-time reverse transcription-polymerase chain reaction could detect CSFV nucleic acid from the oral fluid as early as 8 d postinfection, which also coincided with the time of initial detection in blood samples. The probability of CSFV detection in oral fluid was identical or even higher than in the corresponding blood sample. Our results support the feasibility of using this sampling method for CSFV genome detection, which may represent an additional cost-effective tool for CSF control.

Hypothesis-based weight-of-evidence evaluation and risk assessment for naphthalene carcinogenesis

PubMed Central

Bailey, Lisa A.; Nascarella, Marc A.; Kerper, Laura E.; Rhomberg, Lorenz R.

2016-01-01

Inhalation of naphthalene causes olfactory epithelial nasal tumors in rats (but not in mice) and benign lung adenomas in mice (but not in rats). The limited available human data have not identified an association between naphthalene exposure and increased respiratory cancer risk. Assessing naphthalene's carcinogenicity in humans, therefore, depends entirely on experimental evidence from rodents. We evaluated the respiratory carcinogenicity of naphthalene in rodents, and its potential relevance to humans, using our Hypothesis-Based Weight-of-Evidence (HBWoE) approach. We systematically and comparatively reviewed data relevant to key elements in the hypothesized modes of action (MoA) to determine which is best supported by the available data, allowing all of the data from each realm of investigation to inform interpretation of one another. Our analysis supports a mechanism that involves initial metabolism of naphthalene to the epoxide, followed by GSH depletion, cytotoxicity, chronic inflammation, regenerative hyperplasia, and tumor formation, with possible weak genotoxicity from downstream metabolites occurring only at high cytotoxic doses, strongly supporting a non-mutagenic threshold MoA in the rat nose. We also conducted a dose–response analysis, based on the likely MoA, which suggests that the rat nasal MoA is not relevant in human respiratory tissues at typical environmental exposures. Our analysis illustrates how a thorough WoE evaluation can be used to support a MoA, even when a mechanism of action cannot be fully elucidated. A non-mutagenic threshold MoA for naphthalene-induced rat nasal tumors should be considered as a basis to determine human relevance and to guide regulatory and risk-management decisions. PMID:26202831

Two-dimensional collective electron magnetotransport, oscillations, and chaos in a semiconductor superlattice

NASA Astrophysics Data System (ADS)

Bonilla, L. L.; Carretero, M.; Segura, A.

2017-12-01

When quantized, traces of classically chaotic single-particle systems include eigenvalue statistics and scars in eigenfuntions. Since 2001, many theoretical and experimental works have argued that classically chaotic single-electron dynamics influences and controls collective electron transport. For transport in semiconductor superlattices under tilted magnetic and electric fields, these theories rely on a reduction to a one-dimensional self-consistent drift model. A two-dimensional theory based on self-consistent Boltzmann transport does not support that single-electron chaos influences collective transport. This theory agrees with existing experimental evidence of current self-oscillations, predicts spontaneous collective chaos via a period doubling scenario, and could be tested unambiguously by measuring the electric potential inside the superlattice under a tilted magnetic field.

Modulation of Multiple Sclerosis and Its Animal Model Experimental Autoimmune Encephalomyelitis by Food and Gut Microbiota

PubMed Central

van den Hoogen, Ward J.; Laman, Jon D.; ’t Hart, Bert A.

2017-01-01

Multiple sclerosis (MS) is an autoimmune neurological disease characterized by chronic inflammation of the central nervous system (CNS), leading to demyelination, axonal damage, and symptoms such as fatigue and disability. Although the cause of MS is not known, the infiltration of peripherally activated immune cells into the CNS has a key pathogenic role. Accumulating evidence supports an important role of diet and gut microbiota in immune-mediated diseases. Preclinical as well as clinical studies suggest a role for gut microbiota and dietary components in MS. Here, we review these recent studies on gut microbiota and dietary interventions in MS and its animal model experimental autoimmune encephalomyelitis. We also propose directions for future research. PMID:28928747

The structure of small, vapor-deposited particles. II - Experimental study of particles with hexagonal profile

NASA Technical Reports Server (NTRS)

Yacaman, M. J.; Heinemann, K.; Yang, C. Y.; Poppa, H.

1979-01-01

'Multiply-twinned' gold particles with hexagonal bright field TEM profile were determined to be icosahedra composed of 20 identical and twin-related tetrahedral building units that do not have an fcc structure. The crystal structure of these slightly deformed tetrahedra is rhombohedral. Experimental evidence supporting this particle model was obtained by selected-zone dark field and weak beam dark field electron microscopy. In conjunction with the results of part I, it has been concluded that multiply-twinned gold particles of pentagonal or hexagonal profile that are found during the early stages of the vapor deposition growth process on alkali halide surfaces do not have an fcc crystal structure, which is in obvious contrast to the structure of bulk gold.

Two-dimensional collective electron magnetotransport, oscillations, and chaos in a semiconductor superlattice.

PubMed

Bonilla, L L; Carretero, M; Segura, A

2017-12-01

When quantized, traces of classically chaotic single-particle systems include eigenvalue statistics and scars in eigenfuntions. Since 2001, many theoretical and experimental works have argued that classically chaotic single-electron dynamics influences and controls collective electron transport. For transport in semiconductor superlattices under tilted magnetic and electric fields, these theories rely on a reduction to a one-dimensional self-consistent drift model. A two-dimensional theory based on self-consistent Boltzmann transport does not support that single-electron chaos influences collective transport. This theory agrees with existing experimental evidence of current self-oscillations, predicts spontaneous collective chaos via a period doubling scenario, and could be tested unambiguously by measuring the electric potential inside the superlattice under a tilted magnetic field.

A preliminary investigation of the mechanism of anti-pain and counter-injury effects of the acupuncture anaesthesia.

PubMed

1976-01-01

In accordance with dialectical materialism and by dint of experimental acupuncture anaesthesia, the present investigation has: (1) Made an objective evaluation of the efficiency of acupuncture anaesthesia. (2) Brought forth some experimental evidence about the material basis of the anti-pain and counter-injury effect of acupuncture anaesthesia as well as the significance of its induction period. (3) Proposed the concept of humoral anaesthesia and its technique in order to improve the efficiency of animal laparotomies with acupuncture anaesthesia. Furthermore, it attempts to offer a theoretical explanation of the process of acupuncture anaesthesia under the combination of Chinese and Western medical theories and thereby gives some support to the "meridian-cerebral cortex-viscera inter-correlation hypothesis."

Exacerbation of experimental autoimmune encephalomyelitis by passive transfer of IgG antibodies from a multiple sclerosis patient responsive to immunoadsorption.

PubMed

Pedotti, Rosetta; Musio, Silvia; Scabeni, Stefano; Farina, Cinthia; Poliani, Pietro Luigi; Colombo, Emanuela; Costanza, Massimo; Berzi, Angela; Castellucci, Fabrizio; Ciusani, Emilio; Confalonieri, Paolo; Hemmer, Bernhard; Mantegazza, Renato; Antozzi, Carlo

2013-09-15

The pathogenic role of antibodies in multiple sclerosis (MS) is still controversial. We transferred to mice with experimental autoimmune encephalomyelitis (EAE), animal model of MS, IgG antibodies purified from a MS patient presenting a dramatic clinical improvement during relapse after selective IgG removal with immunoadsorption. Passive transfer of patient's IgG exacerbated motor paralysis and increased mouse central nervous system (CNS) inflammation and demyelination. Binding of patient's IgG was demonstrated in mouse CNS, with a diffuse staining of white matter oligodendrocytes. These data support a growing body of evidence that antibodies can play an important role in the pathobiology of MS. Copyright © 2013 Elsevier B.V. All rights reserved.

Evidence Combination From an Evolutionary Game Theory Perspective

PubMed Central

Deng, Xinyang; Han, Deqiang; Dezert, Jean; Deng, Yong; Shyr, Yu

2017-01-01

Dempster-Shafer evidence theory is a primary methodology for multi-source information fusion because it is good at dealing with uncertain information. This theory provides a Dempster’s rule of combination to synthesize multiple evidences from various information sources. However, in some cases, counter-intuitive results may be obtained based on that combination rule. Numerous new or improved methods have been proposed to suppress these counter-intuitive results based on perspectives, such as minimizing the information loss or deviation. Inspired by evolutionary game theory, this paper considers a biological and evolutionary perspective to study the combination of evidences. An evolutionary combination rule (ECR) is proposed to help find the most biologically supported proposition in a multi-evidence system. Within the proposed ECR, we develop a Jaccard matrix game (JMG) to formalize the interaction between propositions in evidences, and utilize the replicator dynamics to mimick the evolution of propositions. Experimental results show that the proposed ECR can effectively suppress the counter-intuitive behaviors appeared in typical paradoxes of evidence theory, compared with many existing methods. Properties of the ECR, such as solution’s stability and convergence, have been mathematically proved as well. PMID:26285231

Environmental conditions shape the temporal pattern of investment in reproduction and survival.

PubMed

Marasco, Valeria; Boner, Winnie; Griffiths, Kate; Heidinger, Britt; Monaghan, Pat

2018-01-10

The relationship between environmental stress exposure and ageing is likely to vary with stressor severity, life-history stage and the time scale over which effects are measured. Such factors could influence whether stress exposure accelerates or slows the ageing process, but their interactions have not previously been experimentally investigated. We found that experimental exposure of zebra finches to mildly challenging environmental circumstances from young to old adulthood, which increased exposure to stress hormones, reduced breeding performance during early adulthood, but had positive effects when individuals were bred in old adulthood. This difference was not due to selective mortality, because the effects were evident within individuals, and no evidence of habituation in the response to the stressor was found. The more stressful environment had no effects on survival during young or old adulthood, but substantially improved survival during middle age. Changes in the effects at different ages could be due to the duration and nature of the challenging exposure, or to variation in coping capacity or strategy with age. These results show that living under challenging environmental circumstances can influence ageing trajectories in terms of both reproductive performance and longevity. Our results provide experimental support for the emerging idea that stress exposure needs to be optimized rather than minimized to obtain the best health outcomes. © 2018 The Author(s).

Sexual selection explains sex-specific growth plasticity and positive allometry for sexual size dimorphism in a reef fish

PubMed Central

Walker, Stefan P. W.; McCormick, Mark I.

2009-01-01

In 1950, Rensch noted that in clades where males are the larger sex, sexual size dimorphism (SSD) tends to be more pronounced in larger species. This fundamental allometric relationship is now known as ‘Rensch's rule’. While most researchers attribute Rensch's rule to sexual selection for male size, experimental evidence is lacking. Here, we suggest that ultimate hypotheses for Rensch's rule should also apply to groups of individuals and that individual trait plasticity can be used to test those hypotheses experimentally. Specifically, we show that in the sex-changing fish Parapercis cylindrica, larger males have larger harems with larger females, and that SSD increases with harem size. Thus, sexual selection for male body size is the ultimate cause of sexual size allometry. In addition, we experimentally illustrate a positive relationship between polygyny potential and individual growth rate during sex change from female to male. Thus, sexual selection is the ultimate cause of variation in growth rate, and variation in growth rate is the proximate cause of sexual size allometry. Taken together, our results provide compelling evidence in support of the sexual selection hypothesis for Rensch's rule and highlight the potential importance of individual growth modification in the shaping of morphological patterns in Nature. PMID:19553253

Effects of surface roughness and absorption on light propagation in graded-profile waveguides

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

Danilenko, S S; Osovitskii, A N

2011-06-30

This paper examines the effects of surface roughness and absorption on laser light propagation in graded-profile waveguiding structures. We derive analytical expressions for the scattering and absorption coefficients of guided waves and analyse these coefficients in relation to parameters of the waveguiding structure and the roughness of its boundary. A new approach is proposed to measuring roughness parameters of precision dielectric surfaces. Experimental evidence is presented which supports the main conclusions of the theory. (integraled-optical waweguides)

Coupling of lipid membrane elasticity and in-plane dynamics

NASA Astrophysics Data System (ADS)

Tsang, Kuan-Yu; Lai, Yei-Chen; Chiang, Yun-Wei; Chen, Yi-Fan

2017-07-01

Biomembranes exhibit liquid and solid features concomitantly with their in-plane fluidity and elasticity tightly regulated by cells. Here, we present experimental evidence supporting the existence of the dynamics-elasticity correlations for lipid membranes and propose a mechanism involving molecular packing densities to explain them. This paper thereby unifies, at the molecular level, the aspects of the continuum mechanics long used to model the two membrane features. This ultimately may elucidate the universal physical principles governing the cellular phenomena involving biomembranes.

A Rolling Element Tribometer for the Study of Liquid Lubricants in Vacuum

NASA Technical Reports Server (NTRS)

Pepper, Stephen V.; Ebihara, Ben T.; Kingsbury, Edward

1996-01-01

A tribometer for the evaluation of liquid lubricants in vacuum is described. This tribometer is essentially a thrust bearing with three balls and flat races having contact stresses and ball motions similar to those in an angular contact ball bearing operating in the boundary lubrication regime. The friction coefficient, lubrication lifetime, and species evolved from the liquid lubricant by tribodegradation can be determined. A complete analysis of the contact stresses and energy dissipation together with experimental evidence supporting the analysis are presented.

Navigating the gluten-free boom.

PubMed

Gaesser, Glenn A; Angadi, Siddhartha S

2015-08-01

Gluten-free diets have gained popularity with the public at a rate greater than would be expected based on the prevalence of gluten-related disorders such celiac disease, nonceliac gluten sensitivity, and wheat allergy. This article reviews gluten-related disorders, indications for gluten-free diets, and the possible health benefits of gluten. Despite the health claims for gluten-free eating, no published experimental evidence supports weight-loss with a gluten-free diet or suggests that the general population would benefit from avoiding gluten.

Observation of migrating transverse Anderson localizations of light in nonlocal media.

PubMed

Leonetti, Marco; Karbasi, Salman; Mafi, Arash; Conti, Claudio

2014-05-16

We report the experimental observation of the interaction and attraction of many localized modes in a two-dimensional system realized by a disordered optical fiber supporting transverse Anderson localization. We show that a nonlocal optically nonlinear response of thermal origin alters the localization length by an amount determined by the optical power and also induces an action at a distance between the localized modes and their spatial migration. Evidence of a collective and strongly interacting regime is given.

An epidemiological examination of the subluxation construct using Hill's criteria of causation.

PubMed

Mirtz, Timothy A; Morgan, Lon; Wyatt, Lawrence H; Greene, Leon

2009-12-02

Chiropractors claim to locate, analyze and diagnose a putative spinal lesion known as subluxation and apply the mode of spinal manipulation (adjustment) for the correction of this lesion. The purpose of this examination is to review the current evidence on the epidemiology of the subluxation construct and to evaluate the subluxation by applying epidemiologic criteria for it's significance as a causal factor. The databases of PubMed, Cinahl, and Mantis were searched for studies using the keywords subluxation, epidemiology, manipulation, dose-response, temporality, odds ratio, relative risk, biological plausibility, coherence, and analogy. The criteria for causation in epidemiology are strength (strength of association), consistency, specificity, temporality (temporal sequence), dose response, experimental evidence, biological plausibility, coherence, and analogy. Applied to the subluxation all of these criteria remain for the most part unfulfilled. There is a significant lack of evidence to fulfill the basic criteria of causation. This lack of crucial supportive epidemiologic evidence prohibits the accurate promulgation of the chiropractic subluxation.

An epidemiological examination of the subluxation construct using Hill's criteria of causation

PubMed Central

2009-01-01

Background Chiropractors claim to locate, analyze and diagnose a putative spinal lesion known as subluxation and apply the mode of spinal manipulation (adjustment) for the correction of this lesion. Aim The purpose of this examination is to review the current evidence on the epidemiology of the subluxation construct and to evaluate the subluxation by applying epidemiologic criteria for it's significance as a causal factor. Methods The databases of PubMed, Cinahl, and Mantis were searched for studies using the keywords subluxation, epidemiology, manipulation, dose-response, temporality, odds ratio, relative risk, biological plausibility, coherence, and analogy. Results The criteria for causation in epidemiology are strength (strength of association), consistency, specificity, temporality (temporal sequence), dose response, experimental evidence, biological plausibility, coherence, and analogy. Applied to the subluxation all of these criteria remain for the most part unfulfilled. Conclusion There is a significant lack of evidence to fulfill the basic criteria of causation. This lack of crucial supportive epidemiologic evidence prohibits the accurate promulgation of the chiropractic subluxation. PMID:19954544

Dissemination and implementation of evidence based, mental health interventions in post conflict, low resource settings

PubMed Central

Tol, Wietse; Jordans, Mark; Zangana, Goran Sabir; Amin, Ahmed Mohammed; Bolton, Paul; Bass, Judith; Bonilla-Escobar, Fransisco Javier; Thornicroft, Graham

2014-01-01

The burden of mental health problems in (post)conflict low- and middle-income countries (LMIC) is substantial. Despite growing evidence for the effectiveness of selected mental health programs in conflict-affected LMIC and growing policy support, actual uptake and implementation have been slow. A key direction for future research, and a new frontier within science and practice, is Dissemination and Implementation (DI) which directly addresses the movement of evidence-based, effective health care approaches from experimental settings into routine use. This paper outlines some key implementation challenges, and strategies to address these, while implementing evidence-based treatments in conflict-affected LMIC based on the authors’ collective experiences. Dissemination and implementation evaluation and research in conflict settings is an essential new research direction. Future DI work in LMIC should include: 1) defining concepts and developing measurement tools, 2) the measurement of DI outcomes for all programming, and 3) the systematic evaluation of specific implementation strategies. PMID:28316559

Perceiving expressions of emotion: What evidence could bear on questions about perceptual experience of mental states?

PubMed

Butterfill, Stephen A

2015-11-01

What evidence could bear on questions about whether humans ever perceptually experience any of another's mental states, and how might those questions be made precise enough to test experimentally? This paper focusses on emotions and their expression. It is proposed that research on perceptual experiences of physical properties provides one model for thinking about what evidence concerning expressions of emotion might reveal about perceptual experiences of others' mental states. This proposal motivates consideration of the hypothesis that categorical perception of expressions of emotion occurs, can be facilitated by information about agents' emotions, and gives rise to phenomenal expectations. It is argued that the truth of this hypothesis would support a modest version of the claim that humans sometimes perceptually experience some of another's mental states. Much available evidence is consistent with, but insufficient to establish, the truth of the hypothesis. We are probably not yet in a position to know whether humans ever perceptually experience others' mental states. Copyright © 2015 Elsevier Inc. All rights reserved.

Physical Activity and the Prevention of Hypertension

PubMed Central

Diaz, Keith M.; Shimbo, Daichi

2013-01-01

As the worldwide prevalence of hypertension continues to increase, the primary prevention of hypertension has become an important global public health initiative. Physical activity is commonly recommended as an important lifestyle modification that may aid in the prevention of hypertension. Recent epidemiologic evidence has demonstrated a consistent, temporal, and dose-dependent relationship between physical activity and the development of hypertension. Experimental evidence from interventional studies have further confirmed a relationship between physical activity and hypertension as the favorable effects of exercise on blood pressure reduction have been well characterized in recent years. Despite the available evidence strongly supporting a role for physical activity in the prevention of hypertension, many unanswered questions regarding the protective benefits of physical activity in high-risk individuals, the factors that may moderate the relationship between physical activity and hypertension, and the optimal prescription for hypertension prevention remain. We review the most recent evidence for the role of physical activity in the prevention of hypertension and discuss recent studies that have sought to address these unanswered questions. PMID:24052212

Evaluation of seven hypotheses for metamemory performance in rhesus monkeys

PubMed Central

Basile, Benjamin M.; Schroeder, Gabriel R.; Brown, Emily Kathryn; Templer, Victoria L.; Hampton, Robert R.

2014-01-01

Knowing the extent to which nonhumans and humans share mechanisms for metacognition will advance our understanding of cognitive evolution and will improve selection of model systems for biomedical research. Some nonhuman species avoid difficult cognitive tests, seek information when ignorant, or otherwise behave in ways consistent with metacognition. There is agreement that some nonhuman animals “succeed” in these metacognitive tasks, but little consensus about the cognitive mechanisms underlying performance. In one paradigm, rhesus monkeys visually searched for hidden food when ignorant of the location of the food, but acted immediately when knowledgeable. This result has been interpreted as evidence that monkeys introspectively monitored their memory to adaptively control information seeking. However, convincing alternative hypotheses have been advanced that might also account for the adaptive pattern of visual searching. We evaluated seven hypotheses using a computerized task in which monkeys chose either to take memory tests immediately or to see the answer again before proceeding to the test. We found no evidence to support the hypotheses of behavioral cue association, rote response learning, expectancy violation, response competition, generalized search strategy, or postural mediation. In contrast, we repeatedly found evidence to support the memory monitoring hypothesis. Monkeys chose to see the answer when memory was poor, either from natural variation or experimental manipulation. We found limited evidence that monkeys also monitored the fluency of memory access. Overall, the evidence indicates that rhesus monkeys can use memory strength as a discriminative cue for information seeking, consistent with introspective monitoring of explicit memory. PMID:25365530

Assessing the Claims of Participatory Measurement, Reporting and Verification (PMRV) in Achieving REDD+ Outcomes: A Systematic Review

PubMed Central

Hawthorne, Sandra; Boissière, Manuel; Felker, Mary Elizabeth; Atmadja, Stibniati

2016-01-01

Participation of local communities in the Measurement, Reporting and Verification (MRV) of forest changes has been promoted as a strategy that lowers the cost of MRV and increases their engagement with REDD+. This systematic review of literature assessed the claims of participatory MRV (PMRV) in achieving REDD+ outcomes. We identified 29 PMRV publications that consisted of 20 peer-reviewed and 9 non peer-reviewed publications, with 14 publications being empirically based studies. The evidence supporting PMRV claims was categorized into empirical finding, citation or assumption. Our analysis of the empirical studies showed that PMRV projects were conducted in 17 countries in three tropical continents and across various forest and land tenure types. Most of these projects tested the feasibility of participatory measurement or monitoring, which limited the participation of local communities to data gathering. PMRV claims of providing accurate local biomass measurements and lowering MRV cost were well-supported with empirical evidence. Claims that PMRV supports REDD+ social outcomes that affect local communities directly, such as increased environmental awareness and equity in benefit sharing, were supported with less empirical evidence than REDD+ technical outcomes. This may be due to the difficulties in measuring social outcomes and the slow progress in the development and implementation of REDD+ components outside of experimental research contexts. Although lessons from other monitoring contexts have been used to support PMRV claims, they are only applicable when the enabling conditions can be replicated in REDD+ contexts. There is a need for more empirical evidence to support PMRV claims on achieving REDD+ social outcomes, which may be addressed with more opportunities and rigorous methods for assessing REDD+ social outcomes. Integrating future PMRV studies into local REDD+ implementations may help create those opportunities, while increasing the participation of local communities as local REDD+ stakeholders. Further development and testing of participatory reporting framework are required to integrate PMRV data with the national database. Publication of empirical PMRV studies is encouraged to guide when, where and how PMRV should be implemented. PMID:27812110

Social cognition in anorexia nervosa: evidence of preserved theory of mind and impaired emotional functioning.

PubMed

Adenzato, Mauro; Todisco, Patrizia; Ardito, Rita B

2012-01-01

The findings of the few studies that have to date investigated the way in which individuals with Anorexia Nervosa (AN) navigate their social environment are somewhat contradictory. We undertook this study to shed new light on the social-cognitive profile of patients with AN, analysing Theory of Mind and emotional functioning. Starting from previous evidence on the role of the amygdala in the neurobiology of AN and in the social cognition, we hypothesise preserved Theory of Mind and impaired emotional functioning in patients with AN. Thirty women diagnosed with AN and thirty-two women matched for education and age were involved in the study. Theory of Mind and emotional functioning were assessed with a set of validated experimental tasks. A measure of perceived social support was also used to test the correlations between this dimension and the social-cognitive profile of AN patients. The performance of patients with AN is significantly worse than that of healthy controls on tasks assessing emotional functioning, whereas patients' performance is comparable to that of healthy controls on the Theory of Mind task. Correlation analyses showed no relationship between scores on any of the social-cognition tasks and either age of onset or duration of illness. A correlation between social support and emotional functioning was found. This latter result seems to suggest a potential role of social support in the treatment and recovery of AN. The pattern of results followed the experimental hypothesis. They may be useful to help us better understand the social-cognitive profile of patients with AN and to contribute to the development of effective interventions based on the ways in which patients with AN actually perceive their social environment.

Evaluation of cardiovascular risks of spaceflight does not support the NASA bioastronautics critical path roadmap.

PubMed

Convertino, Victor A; Cooke, William H

2005-09-01

Occurrence of serious cardiac dysrhythmias and diminished cardiac and vascular function are the primary cardiovascular risks of spaceflight identified in the 2005 NASA Bioastronautics Critical Path Roadmap. A review of the literature was conducted on experimental results and observational data obtained from spaceflight and relevant ground simulation studies that addressed occurrence of cardiac dysrhythmias, cardiac contractile and vascular function, manifestation of asymptomatic cardiovascular disease, orthostatic intolerance, and response to exercise stress. Based on data from astronauts who have flown in space, there is no compelling experimental evidence to support significant occurrence of cardiac dysrhythmias, manifestation of asymptomatic cardiovascular disease, or reduction in myocardial contractile function. Although there are post-spaceflight data that demonstrate lower peripheral resistance in astronauts who become presyncopal compared with non-presyncopal astronauts, it is not clear that these differences are the result of decreased vascular function. However, the evidence of postflight orthostatic intolerance and reduced exercise capacity is well substantiated by both spaceflight and ground experiments. Although attenuation of baroreflex function(s) may contribute to postflight orthostatic instability, a primary mechanism of orthostatic intolerance and reduced exercise capacity is reduced end-diastolic and stroke volume associated with lower blood volumes and consequent cardiac remodeling. Data from the literature on the current population of astronauts support the notion that the primary cardiovascular risks of spaceflight are compromised hemodynamic responses to central hypovolemia resulting in reduced orthostatic tolerance and exercise capacity rather than occurrence of cardiac dysrhythmias, reduced cardiac contractile and vascular function, or manifestation of asymptomatic cardiovascular disease. These observations warrant a critical review and revision of the 2005 Bioastronautics Critical Path Roadmap.

Proper assessment of the JFK assassination bullet lead evidence from metallurgical and statistical perspectives.

PubMed

Randich, Erik; Grant, Patrick M

2006-07-01

The bullet evidence in the JFK assassination investigation was reexamined from metallurgical and statistical standpoints. The questioned specimens are comprised of soft lead, possibly from full-metal-jacketed Mannlicher-Carcano (MC), 6.5-mm ammunition. During lead refining, contaminant elements are removed to specified levels for a desired alloy or composition. Microsegregation of trace and minor elements during lead casting and processing can account for the experimental variabilities measured in various evidentiary and comparison samples by laboratory analysts. Thus, elevated concentrations of antimony and copper at crystallographic grain boundaries, the widely varying sizes of grains in MC bullet lead, and the 5-60 mg bullet samples analyzed for assassination intelligence effectively resulted in operational sampling error for the analyses. This deficiency was not considered in the original data interpretation and resulted in an invalid conclusion in favor of the single-bullet theory of the assassination. Alternate statistical calculations, based on the historic analytical data, incorporating weighted averaging and propagation of experimental uncertainties also considerably weaken support for the single-bullet theory. In effect, this assessment of the material composition of the lead specimens from the assassination concludes that the extant evidence is consistent with any number between two and five rounds fired in Dealey Plaza during the shooting.

Proper Assessment of the JFK Assassination Bullet Lead Evidence from Metallurgical and Statistical Perspectives

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

Randich, E; Grant, P M

2006-08-29

The bullet evidence in the JFK assassination investigation was reexamined from metallurgical and statistical standpoints. The questioned specimens are comprised of soft lead, possibly from full-metal-jacketed Mannlicher-Carcano, 6.5-mm ammunition. During lead refining, contaminant elements are removed to specified levels for a desired alloy or composition. Microsegregation of trace and minor elements during lead casting and processing can account for the experimental variabilities measured in various evidentiary and comparison samples by laboratory analysts. Thus, elevated concentrations of antimony and copper at crystallographic grain boundaries, the widely varying sizes of grains in Mannlicher-Carcano bullet lead, and the 5-60 mg bullet samples analyzedmore » for assassination intelligence effectively resulted in operational sampling error for the analyses. This deficiency was not considered in the original data interpretation and resulted in an invalid conclusion in favor of the single-bullet theory of the assassination. Alternate statistical calculations, based on the historic analytical data, incorporating weighted averaging and propagation of experimental uncertainties also considerably weaken support for the single-bullet theory. In effect, this assessment of the material composition of the lead specimens from the assassination concludes that the extant evidence is consistent with any number between two and five rounds fired in Dealey Plaza during the shooting.« less

Integrating alternative splicing detection into gene prediction.

PubMed

Foissac, Sylvain; Schiex, Thomas

2005-02-10

Alternative splicing (AS) is now considered as a major actor in transcriptome/proteome diversity and it cannot be neglected in the annotation process of a new genome. Despite considerable progresses in term of accuracy in computational gene prediction, the ability to reliably predict AS variants when there is local experimental evidence of it remains an open challenge for gene finders. We have used a new integrative approach that allows to incorporate AS detection into ab initio gene prediction. This method relies on the analysis of genomically aligned transcript sequences (ESTs and/or cDNAs), and has been implemented in the dynamic programming algorithm of the graph-based gene finder EuGENE. Given a genomic sequence and a set of aligned transcripts, this new version identifies the set of transcripts carrying evidence of alternative splicing events, and provides, in addition to the classical optimal gene prediction, alternative optimal predictions (among those which are consistent with the AS events detected). This allows for multiple annotations of a single gene in a way such that each predicted variant is supported by a transcript evidence (but not necessarily with a full-length coverage). This automatic combination of experimental data analysis and ab initio gene finding offers an ideal integration of alternatively spliced gene prediction inside a single annotation pipeline.

A review of the evidence regarding associations between attachment theory and experimentally induced pain.

PubMed

Meredith, Pamela Joy

2013-04-01

Theoretical and empirical evidence suggests that adult attachment and pain-related variables are predictably and consistently linked, and that understanding these links may guide pain intervention and prevention efforts. In general, insecure attachment has been portrayed as a risk factor, and secure attachment as a protective factor, for people with chronic pain conditions. In an effort to better understand the relationships among attachment and pain variables, these links have been investigated in pain-free samples using induced-pain techniques. The present paper reviews the available research linking adult attachment and laboratory-induced pain. While the diverse nature of the studies precludes definitive conclusions, together these papers offer support for associations between insecure attachment and a more negative pain experience. The evidence presented in this review highlights areas for further empirical attention, as well as providing some guidance for clinicians who may wish to employ preventive approaches and other interventions informed by attachment theory.

Evidence of chiral bands in even-even nuclei

NASA Astrophysics Data System (ADS)

Petrache, C. M.; Lv, B. F.; Astier, A.; Dupont, E.; Wang, Y. K.; Zhang, S. Q.; Zhao, P. W.; Ren, Z. X.; Meng, J.; Greenlees, P. T.; Badran, H.; Cox, D. M.; Grahn, T.; Julin, R.; Juutinen, S.; Konki, J.; Pakarinen, J.; Papadakis, P.; Partanen, J.; Rahkila, P.; Sandzelius, M.; Saren, J.; Scholey, C.; Sorri, J.; Stolze, S.; Uusitalo, J.; Cederwall, B.; Aktas, Ö.; Ertoprak, A.; Liu, H.; Matta, S.; Subramaniam, P.; Guo, S.; Liu, M. L.; Zhou, X. H.; Wang, K. L.; Kuti, I.; Timár, J.; Tucholski, A.; Srebrny, J.; Andreoiu, C.

2018-04-01

Evidence for chiral doublet bands has been observed for the first time in the even-even nucleus 136Nd. One chiral band was firmly established. Four other candidates for chiral bands were also identified, which can contribute to the realization of the multiple pairs of chiral doublet bands (M χ D ) phenomenon. The observed bands are investigated by the constrained and tilted axis cranking covariant density functional theory (TAC-CDFT). Possible configurations have been explored. The experimental energy spectra, angular momenta, and B (M 1 )/B (E 2 ) values for the assigned configurations are globally reproduced by TAC-CDFT. Calculated results support the chiral interpretation of the observed bands, which correspond to shapes with maximum triaxiality induced by different multiquasiparticle configurations in 136Nd.

Disrupted prediction-error signal in psychosis: evidence for an associative account of delusions

PubMed Central

Corlett, P. R.; Murray, G. K.; Honey, G. D.; Aitken, M. R. F.; Shanks, D. R.; Robbins, T.W.; Bullmore, E.T.; Dickinson, A.; Fletcher, P. C.

2012-01-01

Delusions are maladaptive beliefs about the world. Based upon experimental evidence that prediction error—a mismatch between expectancy and outcome—drives belief formation, this study examined the possibility that delusions form because of disrupted prediction-error processing. We used fMRI to determine prediction-error-related brain responses in 12 healthy subjects and 12 individuals (7 males) with delusional beliefs. Frontal cortex responses in the patient group were suggestive of disrupted prediction-error processing. Furthermore, across subjects, the extent of disruption was significantly related to an individual’s propensity to delusion formation. Our results support a neurobiological theory of delusion formation that implicates aberrant prediction-error signalling, disrupted attentional allocation and associative learning in the formation of delusional beliefs. PMID:17690132

Is the devil in the detail? Evidence for S-S learning after unconditional stimulus revaluation in human evaluative conditioning under a broader set of experimental conditions.

PubMed

Jensen-Fielding, Hannah; Luck, Camilla C; Lipp, Ottmar V

2017-11-28

Whether valence change during evaluative conditioning is mediated by a link between the conditional stimulus (CS) and the unconditional stimulus (US; S-S learning) or between the CS and the unconditional response (S-R learning) is a matter of continued debate. Changing the valence of the US after conditioning, known as US revaluation, can be used to dissociate these accounts. Changes in CS valence after US revaluation provide evidence for S-S learning but if CS valence does not change, evidence for S-R learning is found. Support for S-S learning has been provided by most past revaluation studies, but typically the CS and US have been from the same stimulus category, the task instructions have suggested that judgements of the CS should be based on the US, and USs have been mildly valenced stimuli. These factors may bias the results in favour of S-S learning. We examined whether S-R learning would be evident when CSs and USs were taken from different categories, the task instructions were removed, and more salient USs were used. US revaluation was found to influence explicit US evaluations and explicit and implicit CS evaluations, supporting an S-S learning account and suggesting that past results are stable across procedural changes.

Ankle and hip postural strategies defined by joint torques

NASA Technical Reports Server (NTRS)

Runge, C. F.; Shupert, C. L.; Horak, F. B.; Zajac, F. E.; Peterson, B. W. (Principal Investigator)

1999-01-01

Previous studies have identified two discrete strategies for the control of posture in the sagittal plane based on EMG activations, body kinematics, and ground reaction forces. The ankle strategy was characterized by body sway resembling a single-segment-inverted pendulum and was elicited on flat support surfaces. In contrast, the hip strategy was characterized by body sway resembling a double-segment inverted pendulum divided at the hip and was elicited on short or compliant support surfaces. However, biomechanical optimization models have suggested that hip strategy should be observed in response to fast translations on a flat surface also, provided the feet are constrained to remain in contact with the floor and the knee is constrained to remain straight. The purpose of this study was to examine the experimental evidence for hip strategy in postural responses to backward translations of a flat support surface and to determine whether analyses of joint torques would provide evidence for two separate postural strategies. Normal subjects standing on a flat support surface were translated backward with a range of velocities from fast (55 cm/s) to slow (5 cm/s). EMG activations and joint kinematics showed pattern changes consistent with previous experimental descriptions of mixed hip and ankle strategy with increasing platform velocity. Joint torque analyses revealed the addition of a hip flexor torque to the ankle plantarflexor torque during fast translations. This finding indicates the addition of hip strategy to ankle strategy to produce a continuum of postural responses. Hip torque without accompanying ankle torque (pure hip strategy) was not observed. Although postural control strategies have previously been defined by how the body moves, we conclude that joint torques, which indicate how body movements are produced, are useful in defining postural control strategies. These results also illustrate how the biomechanics of the body can transform discrete control patterns into a continuum of postural corrections.

Understanding avian egg cuticle formation in the oviduct: a study of its origin and deposition†

PubMed Central

Wilson, Peter W.; Suther, Ceara S.; Bain, Maureen M.; Icken, Wiebke; Jones, Anita; Quinlan-Pluck, Fiona; Olori, Victor; Gautron, Joël

2017-01-01

Abstract The cuticle is a unique invisible oviduct secretion that protects avian eggs from bacterial penetration through gas exchange pores. Despite its importance, experimental evidence is lacking for where, when, and what is responsible for its deposition. By using knowledge about the ovulatory cycle and oviposition, we have manipulated cuticle deposition to obtain evidence on these key points. Cuticle deposition was measured using staining and spectrophotometry. Experimental evidence supports the location of cuticle deposition to be the shell gland pouch (uterus), not the vagina, and the time of deposition to be within the final hour before oviposition. Oviposition induced by arginine vasotocin or prostaglandin, the penultimate and ultimate factors for the induction of oviposition, produces an egg with no cuticle; therefore, these factors are not responsible for cuticle secretion. Conversely, oviposition induced by GNRH, which mimics the normal events of ovulation and oviposition, results in a normal cuticle. There is no evidence that cuticle deposition differs at the end of a clutch and, therefore, there is no evidence that the ovulatory surge of progesterone affects cuticle deposition. Overall, the results demonstrate that the cuticle is a specific secretion and is not merely an extension of the organic matrix of the shell. Cuticle deposition was found to be reduced by an environmental stressor, and there is no codependence of the deposition of pigment and cuticle. Defining the basic facts surrounding cuticle deposition will help reduce contamination of hen's eggs and increase understanding of the strategies birds use to protect their eggs. PMID:28859284

Folate and asthma.

PubMed

Blatter, Joshua; Han, Yueh-Ying; Forno, Erick; Brehm, John; Bodnar, Lisa; Celedón, Juan C

2013-07-01

Findings from experimental studies and animal models led to the hypothesis that folic acid supplementation during pregnancy confers an increased risk of asthma. This review provides a critical examination of current experimental and epidemiologic evidence of a causal association between folate status and asthma. In industrialized nations, the prevalence of asthma was rising before widespread fortification of foodstuffs with folic acid or folate supplementation before or during pregnancy, thus suggesting that changes in folate status are an unlikely explanation for "the asthma epidemic." Consistent with this ecologic observation, evidence from human studies does not support moderate or strong effects of folate status on asthma. Given known protective effects against neural tube and cardiac defects, there is no reason to alter current recommendations for folic acid supplementation during conception or pregnancy based on findings for folate and asthma. Although we believe that there are inadequate data to exclude a weak effect of maternal folate status on asthma or asthma symptoms, such effects could be examined within the context of very large (and ongoing) birth cohort studies. At this time, there is no justification for funding new studies of folate and asthma.

Water ascent in trees and lianas: the cohesion-tension theory revisited in the wake of Otto Renner.

PubMed

Bentrup, Friedrich-Wilhelm

2017-03-01

The cohesion-tension theory of water ascent (C-T) has been challenged over the past decades by a large body of experimental evidence obtained by means of several minimum or non-invasive techniques. The evidence strongly suggests that land plants acquire water through interplay of several mechanisms covered by the multi-force theory of (U. Zimmermann et al. New Phytologist 162: 575-615, 2004). The diversity of mechanisms includes, for instance, water acquisition by inverse transpiration and thermodynamically uphill transmembrane water secretion by cation-chloride cotransporters (L.H. Wegner, Progress in Botany 76:109-141, 2014). This whole plant perspective was opened by Otto Renner at the beginning of the last century who supported experimentally the strictly xylem-bound C-T mechanism, yet anticipated that the water ascent involves both the xylem conduit and parenchyma tissues. The survey also illustrates the known paradigm that new techniques generate new insights, as well as a paradigm experienced by Max Planck that a new scientific idea is not welcomed by the community instantly.

The dynamic crossover in water does not require bulk water.

PubMed

Turton, David A; Corsaro, Carmelo; Martin, David F; Mallamace, Francesco; Wynne, Klaas

2012-06-14

Many of the anomalous properties of water may be explained by invoking a second critical point that terminates the coexistence line between the low- and high-density amorphous states in the liquid. Direct experimental evidence of this point, and the associated polyamorphic liquid-liquid transition, is elusive as it is necessary for liquid water to be cooled below its homogeneous-nucleation temperature. To avoid crystallization, water in the eutectic LiCl solution has been studied but then it is generally considered that "bulk" water cannot be present. However, recent computational and experimental studies observe cooperative hydration in which case it is possible that sufficient hydrogen-bonded water is present for the essential characteristics of water to be preserved. For femtosecond optical Kerr-effect and nuclear magnetic resonance measurements, we observe in each case a fractional Stokes-Einstein relation with evidence of the dynamic crossover appearing near 220 K and 250 K respectively. Spectra obtained in the glass state also confirm the complex nature of the hydrogen-bonding modes reported for neat room-temperature water and support predictions of anomalous diffusion due to "worm-hole" structure.

Renal Vascular Structure and Rarefaction

PubMed Central

Chade, Alejandro R.

2014-01-01

An intact microcirculation is vital for diffusion of oxygen and nutrients and for removal of toxins of every organ and system in the human body. The functional and/or anatomical loss of microvessels is known as rarefaction, which can compromise the normal organ function and have been suggested as a possible starting point of several diseases. The purpose of this overview is to discuss the potential underlying mechanisms leading to renal microvascular rarefaction, and the potential consequences on renal function and on the progression of renal damage. Although the kidney is a special organ that receives much more blood than its metabolic needs, experimental and clinical evidence indicates that renal microvascular rarefaction is associated to prevalent cardiovascular diseases such as diabetes, hypertension, and atherosclerosis, either as cause or consequence. On the other hand, emerging experimental evidence using progenitor cells or angiogenic cytokines supports the feasibility of therapeutic interventions capable of modifying the progressive nature of microvascular rarefaction in the kidney. This overview will also attempt to discuss the potential renoprotective mechanisms of the therapeutic targeting of the renal microcirculation. PMID:23720331

Nutrition support in hospitalised adults at nutritional risk.

PubMed

Feinberg, Joshua; Nielsen, Emil Eik; Korang, Steven Kwasi; Halberg Engell, Kirstine; Nielsen, Marie Skøtt; Zhang, Kang; Didriksen, Maria; Lund, Lisbeth; Lindahl, Niklas; Hallum, Sara; Liang, Ning; Xiong, Wenjing; Yang, Xuemei; Brunsgaard, Pernille; Garioud, Alexandre; Safi, Sanam; Lindschou, Jane; Kondrup, Jens; Gluud, Christian; Jakobsen, Janus C

2017-05-19

The prevalence of disease-related malnutrition in Western European hospitals is estimated to be about 30%. There is no consensus whether poor nutritional status causes poorer clinical outcome or if it is merely associated with it. The intention with all forms of nutrition support is to increase uptake of essential nutrients and improve clinical outcome. Previous reviews have shown conflicting results with regard to the effects of nutrition support. To assess the benefits and harms of nutrition support versus no intervention, treatment as usual, or placebo in hospitalised adults at nutritional risk. We searched Cochrane Central Register of Controlled Trials (CENTRAL) in the Cochrane Library, MEDLINE (Ovid SP), Embase (Ovid SP), LILACS (BIREME), and Science Citation Index Expanded (Web of Science). We also searched the World Health Organization International Clinical Trials Registry Platform (www.who.int/ictrp); ClinicalTrials.gov; Turning Research Into Practice (TRIP); Google Scholar; and BIOSIS, as well as relevant bibliographies of review articles and personal files. All searches are current to February 2016. We include randomised clinical trials, irrespective of publication type, publication date, and language, comparing nutrition support versus control in hospitalised adults at nutritional risk. We exclude trials assessing non-standard nutrition support. We used standard methodological procedures expected by Cochrane and the Cochrane Hepato-Biliary Group. We used trial domains to assess the risks of systematic error (bias). We conducted Trial Sequential Analyses to control for the risks of random errors. We considered a P value of 0.025 or less as statistically significant. We used GRADE methodology. Our primary outcomes were all-cause mortality, serious adverse events, and health-related quality of life. We included 244 randomised clinical trials with 28,619 participants that met our inclusion criteria. We considered all trials to be at high risk of bias. Two trials accounted for one-third of all included participants. The included participants were heterogenous with regard to disease (20 different medical specialties). The experimental interventions were parenteral nutrition (86 trials); enteral nutrition (tube-feeding) (80 trials); oral nutrition support (55 trials); mixed experimental intervention (12 trials); general nutrition support (9 trials); and fortified food (2 trials). The control interventions were treatment as usual (122 trials); no intervention (107 trials); and placebo (15 trials). In 204/244 trials, the intervention lasted three days or more.We found no evidence of a difference between nutrition support and control for short-term mortality (end of intervention). The absolute risk was 8.3% across the control groups compared with 7.8% (7.1% to 8.5%) in the intervention groups, based on the risk ratio (RR) of 0.94 (95% confidence interval (CI) 0.86 to 1.03, P = 0.16, 21,758 participants, 114 trials, low quality of evidence). We found no evidence of a difference between nutrition support and control for long-term mortality (maximum follow-up). The absolute risk was 13.2% in the control group compared with 12.2% (11.6% to 13%) following nutritional interventions based on a RR of 0.93 (95% CI 0.88 to 0.99, P = 0.03, 23,170 participants, 127 trials, low quality of evidence). Trial Sequential Analysis showed we only had enough information to assess a risk ratio reduction of approximately 10% or more. A risk ratio reduction of 10% or more could be rejected.We found no evidence of a difference between nutrition support and control for short-term serious adverse events. The absolute risk was 9.9% in the control groups versus 9.2% (8.5% to 10%), with nutrition based on the RR of 0.93 (95% CI 0.86 to 1.01, P = 0.07, 22,087 participants, 123 trials, low quality of evidence). At long-term follow-up, the reduction in the risk of serious adverse events was 1.5%, from 15.2% in control groups to 13.8% (12.9% to 14.7%) following nutritional support (RR 0.91, 95% CI 0.85 to 0.97, P = 0.004, 23,413 participants, 137 trials, low quality of evidence). However, the Trial Sequential Analysis showed we only had enough information to assess a risk ratio reduction of approximately 10% or more. A risk ratio reduction of 10% or more could be rejected.Trial Sequential Analysis of enteral nutrition alone showed that enteral nutrition might reduce serious adverse events at maximum follow-up in people with different diseases. We could find no beneficial effect of oral nutrition support or parenteral nutrition support on all-cause mortality and serious adverse events in any subgroup.Only 16 trials assessed health-related quality of life. We performed a meta-analysis of two trials reporting EuroQoL utility score at long-term follow-up and found very low quality of evidence for effects of nutritional support on quality of life (mean difference (MD) -0.01, 95% CI -0.03 to 0.01; 3961 participants, two trials). Trial Sequential Analyses showed that we did not have enough information to confirm or reject clinically relevant intervention effects on quality of life.Nutrition support may increase weight at short-term follow-up (MD 1.32 kg, 95% CI 0.65 to 2.00, 5445 participants, 68 trials, very low quality of evidence). There is low-quality evidence for the effects of nutrition support on mortality and serious adverse events. Based on the results of our review, it does not appear to lead to a risk ratio reduction of approximately 10% or more in either all-cause mortality or serious adverse events at short-term and long-term follow-up.There is very low-quality evidence for an increase in weight with nutrition support at the end of treatment in hospitalised adults determined to be at nutritional risk. The effects of nutrition support on all remaining outcomes are unclear.Despite the clinically heterogenous population and the high risk of bias of all included trials, our analyses showed limited signs of statistical heterogeneity. Further trials may be warranted, assessing enteral nutrition (tube-feeding) for different patient groups. Future trials ought to be conducted with low risks of systematic errors and low risks of random errors, and they also ought to assess health-related quality of life.

Aluminium chloride promotes tumorigenesis and metastasis in normal murine mammary gland epithelial cells

PubMed Central

Tenan, Mirna; Ferrari, Paolo; Sappino, André‐Pascal

2016-01-01

Aluminium salts, present in many industrial products of frequent use like antiperspirants, anti‐acid drugs, food additives and vaccines, have been incriminated in contributing to the rise in breast cancer incidence in Western societies. However, current experimental evidence supporting this hypothesis is limited. For example, no experimental evidence that aluminium promotes tumorigenesis in cultured mammary epithelial cells exists. We report here that long‐term exposure to concentrations of aluminium—in the form of aluminium chloride (AlCl3)—in the range of those measured in the human breast, transform normal murine mammary gland (NMuMG) epithelial cells in vitro as revealed by the soft agar assay. Subcutaneous injections into three different mouse strains with decreasing immunodeficiency, namely, NOD SCID gamma (NSG), NOD SCID or nude mice, revealed that untreated NMuMG cells form tumors and metastasize, to a limited extent, in the highly immunodeficient and natural killer (NK) cell deficient NSG strain, but not in the less permissive and NK cell competent NOD SCID or nude strains. In contrast, NMuMG cells transformed in vitro by AlCl3 form large tumors and metastasize in all three mouse models. These effects correlate with a mutagenic activity of AlCl3. Our findings demonstrate for the first time that concentrations of aluminium in the range of those measured in the human breast fully transform cultured mammary epithelial cells, thus enabling them to form tumors and metastasize in well‐established mouse cancer models. Our observations provide experimental evidence that aluminium salts could be environmental breast carcinogens. PMID:27541736

Is suicide assessment harmful to participants? Findings from a randomized controlled trial.

PubMed

Harris, Keith M; Goh, Melissa Ting-Ting

2017-04-01

There is considerable debate on whether suicide assessment carries an iatrogenic risk for participants/patients. A double-blind randomized controlled trial (registration: R000022314) tested the emotional impact of suicide assessment on participants (n = 259) randomly assigned to experimental (n = 122) or control conditions (n = 137). The experimental condition included the Suicidal Affect-Behavior-Cognition Scale and intensive death-related questions, the control condition a quality of life scale. Both included measures of depression, social support and loneliness. Affective states were assessed immediately before and after testing, and research biases minimized. Post-test debriefing interviews collected qualitative reactions. Experimental participants ranged from nonsuicidal to highly suicidal. Between-groups ANCOVAs and repeated measures ANOVAs showed no differences by study condition, and no pre-post-test affect changes for either condition or suicidal participants (P > 0.10), supporting the null hypothesis of no iatrogenic effects. However, depressive participants in both conditions showed significant decreases in positive affect (P < 0.05). Smallest real difference (SRD) scores approximated clinically meaningful differences and showed 20% of participants had a significant positive survey reaction, 24% a negative reaction, with the rest neutral. Linear regressions revealed depressive symptoms and perceived family support, but not suicidality or other factors, predicted negative affect changes, which was supported by qualitative findings. Social desirability bias was also found in qualitative survey responses. No evidence of iatrogenic effects of suicide assessment were found. Recommendations are made to counter possible negative assessment effects on depressive participants/patients, and nurses and other caregivers are encouraged to talk to patients about suicidal symptoms. © 2016 Australian College of Mental Health Nurses Inc.

Detection of porcine circovirus type 2 and viral replication by in situ hybridization in primary lymphoid organs from naturally and experimentally infected pigs.

PubMed

Hansen, M S; Segalés, J; Fernandes, L T; Grau-Roma, L; Bille-Hansen, V; Larsen, L E; Nielsen, O L

2013-11-01

Porcine circovirus type 2 (PCV2) infection is the cause of postweaning multisystemic wasting syndrome (PMWS). It has been speculated whether cell types permissive of replication are found in the primary lymphoid organs and whether infection of these tissues has an important role in the pathogenesis of PMWS. The aim of this study was to determine if primary lymphoid organ cells support viral replication during PCV2 infection. This was done by histopathological examination of thymus and bone marrow from pigs experimentally inoculated with PCV2 (n = 24), mock-infected pigs (n = 12), pigs naturally affected by PMWS (n = 33), and age-matched healthy control animals (n = 29). In situ hybridization (ISH) techniques were used to detect PCV2 nucleic acid irrespective of replicative status (complementary probe, CP) or to detect only the replicative form of the virus (replicative form probe, RFP). PCV2 was not detected in the experimentally PCV2-inoculated pigs or the control animals. Among the PMWS-affected pigs, 19 of 20 (95%) thymuses were positive for PCV2 by CP ISH, and 7 of 19 (37%) of these also supported viral replication. By CP ISH, PCV2 was detected in 16 of 33 (48%) bone marrow samples, and 5 of 16 (31%) of these also supported replication. The 2 ISH probes labeled the same cell types, which were histiocytes in both organs and lymphocytes in thymus. The RFP labeled fewer cells than the CP. Thus, PCV2 nucleic acids and replication were found in bone marrow and thymus of PMWS-affected pigs, but there was no evidence that primary lymphoid organ cells are major supporters of PCV2 replication.

Scaling in biomechanical experimentation: a finite similitude approach.

PubMed

Ochoa-Cabrero, Raul; Alonso-Rasgado, Teresa; Davey, Keith

2018-06-01

Biological experimentation has many obstacles: resource limitations, unavailability of materials, manufacturing complexities and ethical compliance issues; any approach that resolves all or some of these is of some interest. The aim of this study is applying the recently discovered concept of finite similitude as a novel approach for the design of scaled biomechanical experiments supported with analysis using a commercial finite-element package and validated by means of image correlation software. The study of isotropic scaling of synthetic bones leads to the selection of three-dimensional (3D) printed materials for the trial-space materials. These materials conforming to the theory are analysed in finite-element models of a cylinder and femur geometries undergoing compression, tension, torsion and bending tests to assess the efficacy of the approach using reverse scaling of the approach. The finite-element results show similar strain patterns in the surface for the cylinder with a maximum difference of less than 10% and for the femur with a maximum difference of less than 4% across all tests. Finally, the trial-space, physical-trial experimentation using 3D printed materials for compression and bending testing provides a good agreement in a Bland-Altman statistical analysis, providing good supporting evidence for the practicality of the approach. © 2018 The Author(s).

The Need for Governance by Experimentation: The Case of Biofuels.

PubMed

Asveld, Lotte

2016-06-01

The policies of the European Union concerning the development of biofuels can be termed a lock-in. Biofuels were initially hailed as a green, sustainability technology. However evidence to the contrary quickly emerged. The European Commission proposed to alter its policies to accommodate for these effects but met with fierce resistance from a considerable number of member states who have an economic interest in these first generation biofuels. In this paper I argue that such a lock-in might have been avoided if an experimental approach to governance had been adopted. Existing approaches such as anticipation and niche management either do not reduce uncertainty sufficiently or fail to explicitly address conflicts between values motivating political and economic support for new technologies. In this paper, I suggest to apply an experimental framework to the development of sustainable biobased technologies. Such an approach builds on insights from adaptive management and transition management in that it has the stimulation of learning effects at its core. I argue that these learning effects should occur on the actual impacts of new technologies, on the institutionalisation of new technologies and most specifically on the norms and values that underly policies supporting new technologies. This approach can be relevant for other emerging technologies.

A supportive-educative telephone program: impact on knowledge and anxiety after coronary artery bypass graft surgery.

PubMed

Beckie, T

1989-01-01

The purpose of this study was to investigate the impact of a supportive-educative telephone program on the levels of knowledge and anxiety of patients undergoing coronary artery bypass graft surgery during the first 6 weeks after hospital discharge. With a posttest-only control group design, the first 74 patients scheduled, between September 1986 and February 1987, for coronary artery bypass graft surgery in a large, western Canadian teaching hospital were randomly assigned to either an experimental or a control group. The effect of the intervention, which was implemented by a cardiac rehabilitation nurse specialist, was assessed by a knowledge test and a state anxiety inventory. Data were collected without knowledge of the participants' group assignment. As hypothesized, data analysis with independent t tests revealed a statistically significant (p less than 0.05) difference between the knowledge level of the experimental and the control group in the areas of coronary artery disease, diet, medications, physical activity restrictions, exercise, and rest. A statistically significant difference between the state anxiety level of the experimental and the control group was also evident, as was a statistically significant inverse relationship between participants' knowledge and anxiety levels. From these findings, several implications and recommendations for nursing practice and research have been generated.

Cumulative Weighing of Time in Intertemporal Tradeoffs

PubMed Central

2016-01-01

We examine preferences for sequences of delayed monetary gains. In the experimental literature, two prominent models have been advanced as psychological descriptions of preferences for sequences. In one model, the instantaneous utilities of the outcomes in a sequence are discounted as a function of their delays, and assembled into a discounted utility of the sequence. In the other model, the accumulated utility of the outcomes in a sequence is considered along with utility or disutility from improvement in outcome utilities and utility or disutility from the spreading of outcome utilities. Drawing on three threads of evidence concerning preferences for sequences of monetary gains, we propose that the accumulated utility of the outcomes in a sequence is traded off against the duration of utility accumulation. In our first experiment, aggregate choice behavior provides qualitative support for the tradeoff model. In three subsequent experiments, one of which incentivized, disaggregate choice behavior provides quantitative support for the tradeoff model in Bayesian model contests. One thread of evidence motivating the tradeoff model is that, when, in the choice between two single dated outcomes, it is conveyed that receiving less sooner means receiving nothing later, preference for receiving more later increases, but when it is conveyed that receiving more later means receiving nothing sooner, preference is left unchanged. Our results show that this asymmetric hidden-zero effect is indeed driven by those supporting the tradeoff model. The tradeoff model also accommodates all remaining evidence on preferences for sequences of monetary gains. PMID:27560853

Does exposure to hyperglycaemia in utero increase the risk of obesity and diabetes in the offspring? A critical reappraisal.

PubMed

Donovan, L E; Cundy, T

2015-03-01

The idea that exposure to hyperglycaemia in utero is an important factor in the development of obesity and diabetes in the offspring has become entrenched as popular belief. To appraise the literature supporting this hypothesis in the light of recent studies that have clarified the main drivers of obesity in children and adolescents. A review of published evidence from animal studies, human observational studies, systematic reviews and experimental trials that address the impact of diabetes (Types 1 and 2, genetic or gestational) on the future risk of obesity and/or glucose intolerance in the offspring. Some animal studies support a relationship between exposure to hyperglycaemia in utero and future development of obesity and diabetes, but the results are inconsistent. Most of the human studies claiming to show a relationship have not taken into account important known confounders, such as maternal and paternal BMI. Evidence supporting a dose-response relationship between maternal hyperglycaemia exposure and obesity and diabetes in the offspring is weak, and there is no convincing evidence that treating gestational diabetes reduces the later risk of offspring obesity or glucose intolerance. Exposure to hyperglycaemia in utero has minimal direct effect on the later risk of obesity and Type 2 diabetes. The increased risk of obesity in the offspring of women with Type 2 or gestational diabetes can be explained by confounding factors, such as parental obesity. © 2014 The Authors. Diabetic Medicine © 2014 Diabetes UK.

Standardized description of scientific evidence using the Evidence Ontology (ECO)

PubMed Central

Chibucos, Marcus C.; Mungall, Christopher J.; Balakrishnan, Rama; Christie, Karen R.; Huntley, Rachael P.; White, Owen; Blake, Judith A.; Lewis, Suzanna E.; Giglio, Michelle

2014-01-01

The Evidence Ontology (ECO) is a structured, controlled vocabulary for capturing evidence in biological research. ECO includes diverse terms for categorizing evidence that supports annotation assertions including experimental types, computational methods, author statements and curator inferences. Using ECO, annotation assertions can be distinguished according to the evidence they are based on such as those made by curators versus those automatically computed or those made via high-throughput data review versus single test experiments. Originally created for capturing evidence associated with Gene Ontology annotations, ECO is now used in other capacities by many additional annotation resources including UniProt, Mouse Genome Informatics, Saccharomyces Genome Database, PomBase, the Protein Information Resource and others. Information on the development and use of ECO can be found at http://evidenceontology.org. The ontology is freely available under Creative Commons license (CC BY-SA 3.0), and can be downloaded in both Open Biological Ontologies and Web Ontology Language formats at http://code.google.com/p/evidenceontology. Also at this site is a tracker for user submission of term requests and questions. ECO remains under active development in response to user-requested terms and in collaborations with other ontologies and database resources. Database URL: Evidence Ontology Web site: http://evidenceontology.org PMID:25052702

Quasi-experimental study designs series-paper 13: realizing the full potential of quasi-experiments for health research.

PubMed

Rockers, Peter C; Tugwell, Peter; Røttingen, John-Arne; Bärnighausen, Till

2017-09-01

Although the number of quasi-experiments conducted by health researchers has increased in recent years, there clearly remains unrealized potential for using these methods for causal evaluation of health policies and programs globally. This article proposes five prescriptions for capturing the full value of quasi-experiments for health research. First, new funding opportunities targeting proposals that use quasi-experimental methods should be made available to a broad pool of health researchers. Second, administrative data from health programs, often amenable to quasi-experimental analysis, should be made more accessible to researchers. Third, training in quasi-experimental methods should be integrated into existing health science graduate programs to increase global capacity to use these methods. Fourth, clear guidelines for primary research and synthesis of evidence from quasi-experiments should be developed. Fifth, strategic investments should be made to continue to develop new innovations in quasi-experimental methodologies. Tremendous opportunities exist to expand the use of quasi-experimental methods to increase our understanding of which health programs and policies work and which do not. Health researchers should continue to expand their commitment to rigorous causal evaluation with quasi-experimental methods, and international institutions should increase their support for these efforts. Copyright © 2017 Elsevier Inc. All rights reserved.

A new insight into the interaction of ZnO with calf thymus DNA through surface defects.

PubMed

Das, Sumita; Chatterjee, Sabyasachi; Pramanik, Srikrishna; Devi, Parukuttyamma Sujatha; Kumar, Gopinatha Suresh

2018-01-01

Experimental evidences on the binding interaction of ZnO and Calf Thymus (CT) DNA using several biophysical techniques are the centre of interest of the present study. The interaction of ZnO with CT DNA has been investigated in detail by absorption spectral study, fluorescence titration, Raman analysis, zeta potential measurement, viscometric experiment along with thermal melting study and microscopic analysis. Steady-state fluorescence study revealed the quenching (48%) of the surface defect related peak intensity of ZnO on interaction with DNA. The optimized concentration of ZnO and DNA to obtain this level of quenching has been found to be 0.049mM and 1.027μM, respectively. Additional fluorescence study with 8-hydroxy-5-quinoline (HQ) as a fluorescence probe for Zn 2+ ruled out the dissolution effect of ZnO under the experimental conditions. DNA conjugation on the surface of ZnO was also supported by Raman study. The quantitative variation in conductivity as well as electrophoretic mobility indicated significant interaction of ZnO with the DNA molecule. Circular dichroism (CD) and viscometry titrations provided clear evidence in support of the conformational retention of the DNA on interaction with ZnO. The binding interaction was found to be predominantly entropy driven in nature. The bio-physical studies presented in this paper exploring ZnO-CT DNA interaction could add a new horizon to understand the interaction between metal oxide and DNA. Copyright © 2017. Published by Elsevier B.V.

The role of guilt in Posttraumatic Stress Disorder

PubMed Central

Bub, Konstantin; Lommen, Miriam J. J.

2017-01-01

ABSTRACT Background: A growing body of evidence supports the notion that the emotional profile of Posttraumatic Stress Disorder (PTSD) may be more diverse than traditional accounts presume. PTSD’s image as an anxiety-based disorder is undergoing change as the significance of other emotions in its development becomes more evident. Experimental research is needed in order to expand the understanding of underlying processes driving the development of PTSD. Objective: Experimentally test the influence of stressor-related guilt on the occurrence of PTSD symptomatology. Method: A non-clinical student sample faced an analogue trauma, a stressor in the form of a computer crash and related loss of data. We either personally blamed participants for causing the incident (blame group) or told them that it was a technical failure and therefore not their fault (no-blame group). Levels of guilt before and after the incident as well as number and associated distress of incident-related intrusions were assessed using a one-day diary and compared between groups. Results: The guilt manipulation was successful: feelings of guilt significantly increased in the blame group but not in the no-blame group. Furthermore, the blame group showed a significantly higher number of intrusions and associated distress compared to the no-blame group at one-day follow-up. Conclusions: These laboratory findings indicate that feelings of guilt may lead to increased PTSD symptomatology, supporting the view that guilt experienced in reaction to a traumatic event may be part of a causal mechanism driving the development of PTSD. PMID:29230272

The role of astrocytic glycogen in supporting the energetics of neuronal activity

PubMed Central

DiNuzzo, Mauro; Mangia, Silvia; Maraviglia, Bruno; Giove, Federico

2014-01-01

Energy homeostasis in the brain is maintained by oxidative metabolism of glucose, primarily to fulfil the energy demand associated with ionic movements in neurons and astrocytes. In this contribution we review the experimental evidence that ground a specific role of glycogen metabolism in supporting the functional energetic needs of astrocytes during the removal of extracellular potassium. Based on theoretical considerations, we further discuss the hypothesis that the mobilization of glycogen in astrocytes serves the purpose to enhance the availability of glucose for neuronal glycolytic and oxidative metabolism at the onset of stimulation. Finally, we provide an evolutionary perspective for explaining the selection of glycogen as carbohydrate reserve in the energy-sensing machinery of cell metabolism. PMID:22614927

Brain Energetics During the Sleep-Wake Cycle

PubMed Central

DiNuzzo, Mauro; Nedergaard, Maiken

2017-01-01

Brain activity during wakefulness is associated with high metabolic rates that are believed to support information processing and memory encoding. In spite of loss of consciousness, sleep still carries a substantial energy cost. Experimental evidence supports a cerebral metabolic shift taking place during sleep that suppresses aerobic glycolysis, a hallmark of environment-oriented waking behavior and synaptic plasticity. Recent studies reveal that glial astrocytes respond to the reduction of wake-promoting neuromodulators by regulating volume, composition and glymphatic drainage of interstitial fluid. These events are accompanied by changes in neuronal discharge patterns, astrocyte-neuron interactions, synaptic transactions and underlying metabolic features. Internally-generated neuronal activity and network homeostasis are proposed to account for the high sleep-related energy demand. PMID:29024871

The stress-buffering effects of functional social support on ambulatory blood pressure.

PubMed

Bowen, Kimberly S; Uchino, Bert N; Birmingham, Wendy; Carlisle, McKenzie; Smith, Timothy W; Light, Kathleen C

2014-11-01

Social support is a reliable predictor of cardiovascular health. According to the buffering hypothesis, stress is 1 mechanism by which support is able to affect physiological processes. However, most of the experimental evidence for the hypothesis comes from laboratory studies. Ambulatory blood pressure (ABP) protocols examine participants in their natural environment, where they are more likely to encounter personally relevant real-world stressors. Furthermore, prior work shows that examining support by its specific functional components reveals additional independent links to health. The current study aimed to examine the stress-buffering effects of functional social support on ABP. One hundred eighty-eight participants completed a 1-day ABP assessment along with measures of functional social support and both global perceived stress and momentary stress at time of reading. RESULTS indicated main effects for both stress measures. Global support, emotional, tangible, and informational support only moderated the effects of momentary stress, but not global stress, in predicting ABP. Informational support was the most consistent stress-buffering predictor of ABP, predicting both ambulatory systolic and diastolic blood pressure. The predicted values in ABP for informational support achieved health-relevant differences, emphasizing the value of examining functional support beyond global support alone. PsycINFO Database Record (c) 2014 APA, all rights reserved.

Fruits for Prevention and Treatment of Cardiovascular Diseases

PubMed Central

Zhao, Cai-Ning; Meng, Xiao; Li, Ya; Li, Sha; Liu, Qing; Tang, Guo-Yi; Li, Hua-Bin

2017-01-01

Cardiovascular diseases (CVDs) are leading global health problems. Accumulating epidemiological studies have indicated that consuming fruits was inversely related to the risk of CVDs. Moreover, substantial experimental studies have supported the protective role of fruits against CVDs, and several fruits (grape, blueberry, pomegranate, apple, hawthorn, and avocado) have been widely studied and have shown potent cardiovascular protective action. Fruits can prevent CVDs or facilitate the restoration of morphology and functions of heart and vessels after injury. The involved mechanisms included protecting vascular endothelial function, regulating lipids metabolism, modulating blood pressure, inhibiting platelets function, alleviating ischemia/reperfusion injury, suppressing thrombosis, reducing oxidative stress, and attenuating inflammation. The present review summarizes recent discoveries about the effects of fruits on CVDs and discusses potential mechanisms of actions based on evidence from epidemiological, experimental, and clinical studies. PMID:28608832

Advantages of a polycentric approach to climate change policy

NASA Astrophysics Data System (ADS)

Cole, Daniel H.

2015-02-01

Lack of progress in global climate negotiations has led scholars to reconsider polycentric approaches to climate policy. Several examples of subglobal mechanisms to reduce greenhouse-gas emissions have been touted, but it remains unclear why they might achieve better climate outcomes than global negotiations alone. Decades of work conducted by researchers associated with the Vincent and Elinor Ostrom Workshop in Political Theory and Policy Analysis at Indiana University have emphasized two chief advantages of polycentric approaches over monocentric ones: they provide more opportunities for experimentation and learning to improve policies over time, and they increase communications and interactions -- formal and informal, bilateral and multilateral -- among parties to help build the mutual trust needed for increased cooperation. A wealth of theoretical, empirical and experimental evidence supports the polycentric approach.

Accelerating Recovery from Poverty: Prevention Effects for Recently Separated Mothers.

PubMed

Forgatch, Marion S; Degarmo, David S

2007-01-15

This study evaluated benefits of a preventive intervention to the living standards of recently separated mothers. In the Oregon Divorce Study's randomized experimental design, data were collected 5 times over 30 months and evaluated with Hierarchical Linear Growth Models. Relative to their no-intervention control counterparts, experimental mothers had greater improvements in gross annual income, discretionary annual income, poverty threshold, income-to-needs ratios, and financial stress. Comparisons showed the intervention to produce a greater increase in income-to-needs and a greater rise-above-poverty threshold. Benefits to income-to-needs were statistically independent of maternal depressed mood, divorce status, child support, and repartnering. Financial stress reductions were explained by the intervention effect on income-to-needs. The importance of helping disadvantaged families with evidence-based programs is discussed.

Accelerating Recovery from Poverty: Prevention Effects for Recently Separated Mothers

PubMed Central

Forgatch, Marion S.; DeGarmo, David S.

2008-01-01

This study evaluated benefits of a preventive intervention to the living standards of recently separated mothers. In the Oregon Divorce Study’s randomized experimental design, data were collected 5 times over 30 months and evaluated with Hierarchical Linear Growth Models. Relative to their no-intervention control counterparts, experimental mothers had greater improvements in gross annual income, discretionary annual income, poverty threshold, income-to-needs ratios, and financial stress. Comparisons showed the intervention to produce a greater increase in income-to-needs and a greater rise-above-poverty threshold. Benefits to income-to-needs were statistically independent of maternal depressed mood, divorce status, child support, and repartnering. Financial stress reductions were explained by the intervention effect on income-to-needs. The importance of helping disadvantaged families with evidence-based programs is discussed. PMID:19043620

Distinguishing topological Majorana bound states from trivial Andreev bound states: Proposed tests through differential tunneling conductance spectroscopy

NASA Astrophysics Data System (ADS)

Liu, Chun-Xiao; Sau, Jay D.; Das Sarma, S.

2018-06-01

Trivial Andreev bound states arising from chemical-potential variations could lead to zero-bias tunneling conductance peaks at finite magnetic field in class-D nanowires, precisely mimicking the predicted zero-bias conductance peaks arising from the topological Majorana bound states. This finding raises a serious question on the efficacy of using zero-bias tunneling conductance peaks, by themselves, as evidence supporting the existence of topological Majorana bound states in nanowires. In the current work, we provide specific experimental protocols for tunneling spectroscopy measurements to distinguish between Andreev and Majorana bound states without invoking more demanding nonlocal measurements which have not yet been successfully performed in nanowire systems. In particular, we discuss three distinct experimental schemes involving the response of the zero-bias peak to local perturbations of the tunnel barrier, the overlap of bound states from the wire ends, and, most compellingly, introducing a sharp localized potential in the wire itself to perturb the zero-bias tunneling peaks. We provide extensive numerical simulations clarifying and supporting our theoretical predictions.

Dietary salt intake and risk of gastric cancer.

PubMed

D'Elia, Lanfranco; Galletti, Ferruccio; Strazzullo, Pasquale

2014-01-01

Humans began to use large amounts of salt for the main purpose of food preservation approximately 5,000 years ago and, although since then advanced technologies have been developed allowing drastic reduction in the use of salt for food storage, excess dietary salt intake remains very common. Gastric cancer is a common neoplasia, and dietary factors, including salt consumption, are considered relevant to its causation. A number of experimental studies supported the cocarcinogenic effect of salt through synergic action with Helicobacter pylori infection, in addition to some independent effects such as increase in the rate of cell proliferation and of endogenous mutations. Many epidemiological studies analyzed the relationship between excess salt intake and risk of gastric cancer. Both cross-sectional and prospective studies indicated a possibly dose-dependent positive association. In particular, a comprehensive meta-analysis of longitudinal studies detected a strong adverse effect of total salt intake and salt-rich foods on the risk of gastric cancer in the general population. Altogether, the epidemiological, clinical, and experimental evidence supports the possibility of a substantial reduction in the rates of gastric cancer through progressive reduction in population salt intake.

Effectiveness of befriending interventions: a systematic review and meta-analysis

PubMed Central

Siette, Joyce; Cassidy, Megan; Priebe, Stefan

2017-01-01

Objective Befriending is an emotional supportive relationship in which one-to-one companionship is provided on a regular basis by a volunteer. It is commonly and increasingly offered by the voluntary sector for individuals with distressing physical and mental conditions. However, the effectiveness of this intervention on health outcomes is largely unknown. We aim to conduct a systematic review of the benefits of befriending. Design Systematic review. Methods A systematic search of electronic databases was conducted to identify randomised controlled trials and quasi-experimental trials of befriending for a range of physical and mental health indications including depression, anxiety, mental illness, cancer, physical illness and dementia. Main outcomes included patient-relevant and disease-specific outcomes, such as depression, loneliness, quality of life, self-esteem, social support and well-being. Results A total of 14 trials (2411 participants) were included; 7 were judged at low risk of bias. Most trials showed improvement in symptoms associated with befriending but these associations did not reach statistical significance in all trials. Befriending was significantly associated with better patient-reported outcomes across primary measures (standardised mean difference 0.18 (95% CI, −0.002 to 0.36, I2=26%, seven trials)). However, there was no significant benefit on single outcomes, including depression, quality of life, loneliness ratings, self-esteem measures, social support structures and well-being. Conclusions There was moderate quality evidence to support the use of befriending for the treatment of individuals with different physical and mental health conditions. This evidence refers to an overall improvement benefit in patient-reported primary outcomes, although with a rather small effect size. The current evidence base does not allow for firm conclusions on more specific outcomes. Future trials should hypothesise a model for the precise effects of befriending and use specified inclusion and outcome criteria. PMID:28446525

Working memory training in older adults: Bayesian evidence supporting the absence of transfer.

PubMed

Guye, Sabrina; von Bastian, Claudia C

2017-12-01

The question of whether working memory training leads to generalized improvements in untrained cognitive abilities is a longstanding and heatedly debated one. Previous research provides mostly ambiguous evidence regarding the presence or absence of transfer effects in older adults. Thus, to draw decisive conclusions regarding the effectiveness of working memory training interventions, methodologically sound studies with larger sample sizes are needed. In this study, we investigated whether or not a computer-based working memory training intervention induced near and far transfer in a large sample of 142 healthy older adults (65 to 80 years). Therefore, we randomly assigned participants to either the experimental group, which completed 25 sessions of adaptive, process-based working memory training, or to the active, adaptive visual search control group. Bayesian linear mixed-effects models were used to estimate performance improvements on the level of abilities, using multiple indicator tasks for near (working memory) and far transfer (fluid intelligence, shifting, and inhibition). Our data provided consistent evidence supporting the absence of near transfer to untrained working memory tasks and the absence of far transfer effects to all of the assessed abilities. Our results suggest that working memory training is not an effective way to improve general cognitive functioning in old age. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

Sensory Response of Transplanted Astrocytes in Adult Mammalian Cortex In Vivo

PubMed Central

Zhang, Kuan; Chen, Chunhai; Yang, Zhiqi; He, Wenjing; Liao, Xiang; Ma, Qinlong; Deng, Ping; Lu, Jian; Li, Jingcheng; Wang, Meng; Li, Mingli; Zheng, Lianghong; Zhou, Zhuan; Sun, Wei; Wang, Liting; Jia, Hongbo; Yu, Zhengping; Zhou, Zhou; Chen, Xiaowei

2016-01-01

Glial precursor transplantation provides a potential therapy for brain disorders. Before its clinical application, experimental evidence needs to indicate that engrafted glial cells are functionally incorporated into the existing circuits and become essential partners of neurons for executing fundamental brain functions. While previous experiments supporting for their functional integration have been obtained under in vitro conditions using slice preparations, in vivo evidence for such integration is still lacking. Here, we utilized in vivo two-photon Ca2+ imaging along with immunohistochemistry, fluorescent indicator labeling-based axon tracing and correlated light/electron microscopy to analyze the profiles and the functional status of glial precursor cell-derived astrocytes in adult mouse neocortex. We show that after being transplanted into somatosensory cortex, precursor-derived astrocytes are able to survive for more than a year and respond with Ca2+ signals to sensory stimulation. These sensory-evoked responses are mediated by functionally-expressed nicotinic receptors and newly-established synaptic contacts with the host cholinergic afferents. Our results provide in vivo evidence for a functional integration of transplanted astrocytes into adult mammalian neocortex, representing a proof-of-principle for sensory cortex remodeling through addition of essential neural elements. Moreover, we provide strong support for the use of glial precursor transplantation to understand glia-related neural development in vivo. PMID:27405333

Are there genetic influences on addiction: evidence from family, adoption and twin studies.

PubMed

Agrawal, Arpana; Lynskey, Michael T

2008-07-01

In this exciting era of gene discovery, we review evidence from family, adoption and twin studies that examine the genetic basis for addiction. With a focus on the classical twin design that utilizes data on monozygotic and dizygotic twins, we discuss support in favor of heritable influences on alcohol, nicotine, cannabis and other illicit drug dependence. We review whether these genetic factors also influence earlier stages (e.g. experimentation) of the addictive process and whether there are genetic influences specific to each psychoactive substance. Converging evidence from these studies supports the role of moderate to high genetic influences on addiction with estimates ranging from 0.30 to 0.70. The changing role of these heritable factors as a function of gender, age and cultural characteristics is also discussed. We highlight the importance of the interplay between genes and the environment as it relates to risk for addiction and the utility of the children-of-twins design for emerging studies of gene-environment interaction is presented. Despite the advances being made by low-cost high-throughput whole genome association assays, we posit that information garnered from twin studies, especially extended twin designs with power to examine gene-environment interactions, will continue to form the foundation for genomic research.

Constructing a new theory from old ideas and new evidence

PubMed Central

Rhodes, Marjorie; Wellman, Henry

2014-01-01

A central tenet of constructivist models of conceptual development is that children’s initial conceptual level constrains how they make sense of new evidence and thus whether exposure to evidence will prompt conceptual change. Yet, little experimental evidence directly examines this claim for the case of sustained, fundamental conceptual achievements. The present study combined scaling and experimental microgenetic methods to examine the processes underlying conceptual change in the context of an important conceptual achievement of early childhood—the development of a representational theory of mind. Results from 47 children (M age = 3.7 years) indicate that only children who were conceptually close to understanding false belief at the beginning of the study, and who were experimentally exposed to evidence of people acting on false beliefs, reliably developed representational theories of minds. Combined scaling and microgenetic data revealed how prior conceptual level interacts with experience, thereby providing critical experimental evidence for how conceptual change results from the interplay between conceptions and evidence. PMID:23489194

Beyond Agar: Gel Substrates with Improved Optical Clarity and Drug Efficiency and Reduced Autofluorescence for Microbial Growth Experiments

PubMed Central

McElfresh, Cameron; Wong, Lily R.

2015-01-01

Agar, a seaweed extract, has been the standard support matrix for microbial experiments for over a century. Recent developments in high-throughput genetic screens have created a need to reevaluate the suitability of agar for use as colony support, as modern robotic printing systems now routinely spot thousands of colonies within the area of a single microtiter plate. Identifying optimal biophysical, biochemical, and biological properties of the gel support matrix in these extreme experimental conditions is instrumental to achieving the best possible reproducibility and sensitivity. Here we systematically evaluate a range of gelling agents by using the yeast Saccharomyces cerevisiae as a model microbe. We find that carrageenan and Phytagel have superior optical clarity and reduced autofluorescence, crucial for high-resolution imaging and fluorescent reporter screens. Nutrient choice and use of refined Noble agar or pure agarose reduce the effective dose of numerous selective drugs by >50%, potentially enabling large cost savings in genetic screens. Using thousands of mutant yeast strains to compare colony growth between substrates, we found no evidence of significant growth or nutrient biases between gel substrates, indicating that researchers could freely pick and choose the optimal gel for their respective application and experimental condition. PMID:26070672

Beyond Agar: Gel Substrates with Improved Optical Clarity and Drug Efficiency and Reduced Autofluorescence for Microbial Growth Experiments.

PubMed

Jaeger, Philipp A; McElfresh, Cameron; Wong, Lily R; Ideker, Trey

2015-08-15

Agar, a seaweed extract, has been the standard support matrix for microbial experiments for over a century. Recent developments in high-throughput genetic screens have created a need to reevaluate the suitability of agar for use as colony support, as modern robotic printing systems now routinely spot thousands of colonies within the area of a single microtiter plate. Identifying optimal biophysical, biochemical, and biological properties of the gel support matrix in these extreme experimental conditions is instrumental to achieving the best possible reproducibility and sensitivity. Here we systematically evaluate a range of gelling agents by using the yeast Saccharomyces cerevisiae as a model microbe. We find that carrageenan and Phytagel have superior optical clarity and reduced autofluorescence, crucial for high-resolution imaging and fluorescent reporter screens. Nutrient choice and use of refined Noble agar or pure agarose reduce the effective dose of numerous selective drugs by >50%, potentially enabling large cost savings in genetic screens. Using thousands of mutant yeast strains to compare colony growth between substrates, we found no evidence of significant growth or nutrient biases between gel substrates, indicating that researchers could freely pick and choose the optimal gel for their respective application and experimental condition. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

The existential function of close relationships: introducing death into the science of love.

PubMed

Mikulincer, Mario; Florian, Victor; Hirschberger, Gilad

2003-01-01

Originally, terror management theory proposed two psychological mechanisms in dealing with the terror of death awareness-cultural worldview validation and self-esteem enhancement. In this article, we would like to promote the idea of close relationships as an additional death-anxiety buffering mechanism and review a growing body of empirical data that support this contention. Based on a comprehensive analysis of the sociocultural and personal functions of close relationships, we formulate two basic hypotheses that have received empirical support in a series of experimental studies. First, death reminders heighten the motivation to form and maintain close relationships. Second, the maintenance of close relationships provides a symbolic shield against the terror of death, whereas the breaking of close relationships results in an upsurge of death awareness. In addition, we present empirical evidence supporting the possibility that close relationships function as a related yet separate mechanism from the self-esteem and cultural worldview defenses.

Population and hierarchy of active species in gold iron oxide catalysts for carbon monoxide oxidation.

PubMed

He, Qian; Freakley, Simon J; Edwards, Jennifer K; Carley, Albert F; Borisevich, Albina Y; Mineo, Yuki; Haruta, Masatake; Hutchings, Graham J; Kiely, Christopher J

2016-09-27

The identity of active species in supported gold catalysts for low temperature carbon monoxide oxidation remains an unsettled debate. With large amounts of experimental evidence supporting theories of either gold nanoparticles or sub-nm gold species being active, it was recently proposed that a size-dependent activity hierarchy should exist. Here we study the diverging catalytic behaviours after heat treatment of Au/FeO x materials prepared via co-precipitation and deposition precipitation methods. After ruling out any support effects, the gold particle size distributions in different catalysts are quantitatively studied using aberration corrected scanning transmission electron microscopy (STEM). A counting protocol is developed to reveal the true particle size distribution from HAADF-STEM images, which reliably includes all the gold species present. Correlation of the populations of the various gold species present with catalysis results demonstrate that a size-dependent activity hierarchy must exist in the Au/FeO x catalyst.

Using Dynamic Assessment to Evaluate the Expressive Syntax of Children who use Augmentative and Alternative Communication

PubMed Central

King, Marika R.; Binger, Cathy; Kent-Walsh, Jennifer

2015-01-01

The developmental readiness of four 5-year-old children to produce basic sentences using graphic symbols on an augmentative and alternative communication (AAC) device during a dynamic assessment (DA) task was examined. Additionally, the ability of the DA task to predict performance on a subsequent experimental task was evaluated. A graduated prompting framework was used during DA. Measures included amount of support required to produce the targets, modifiability (change in participant performance) within a DA session, and predictive validity of DA. Participants accurately produced target structures with varying amounts of support. Modifiability within DA sessions was evident for some participants, and partial support was provided for the measures of predictive validity. These initial results indicate that DA may be a viable way to measure young children’s developmental readiness to learn how to sequence simple, rule-based messages via aided AAC. PMID:25621928

The impact of pretend play on children's development: a review of the evidence.

PubMed

Lillard, Angeline S; Lerner, Matthew D; Hopkins, Emily J; Dore, Rebecca A; Smith, Eric D; Palmquist, Carolyn M

2013-01-01

Pretend play has been claimed to be crucial to children's healthy development. Here we examine evidence for this position versus 2 alternatives: Pretend play is 1 of many routes to positive developments (equifinality), and pretend play is an epiphenomenon of other factors that drive development. Evidence from several domains is considered. For language, narrative, and emotion regulation, the research conducted to date is consistent with all 3 positions but insufficient to draw conclusions. For executive function and social skills, existing research leans against the crucial causal position but is insufficient to differentiate the other 2. For reasoning, equifinality is definitely supported, ruling out a crucially causal position but still leaving open the possibility that pretend play is epiphenomenal. For problem solving, there is no compelling evidence that pretend play helps or is even a correlate. For creativity, intelligence, conservation, and theory of mind, inconsistent correlational results from sound studies and nonreplication with masked experimenters are problematic for a causal position, and some good studies favor an epiphenomenon position in which child, adult, and environment characteristics that go along with play are the true causal agents. We end by considering epiphenomenalism more deeply and discussing implications for preschool settings and further research in this domain. Our take-away message is that existing evidence does not support strong causal claims about the unique importance of pretend play for development and that much more and better research is essential for clarifying its possible role. (PsycINFO Database Record (c) 2013 APA, all rights reserved).

Scientific evidence and research in antimicrobial stewardship.

PubMed

Almirante, Benito; Garnacho-Montero, José; Pachón, Jerónimo; Pascual, Álvaro; Rodríguez-Baño, Jesús

2013-09-01

Evaluating the impact of antibiotic stewardship programs is challenging. There is evidence that they are effective in terms of reducing the consumption and cost of antibiotics, although establishing their impact on antimicrobial resistance (beyond restrictive policies in outbreaks caused by specific antimicrobial resistant organisms) and clinical outcomes is more difficult. Proper definitions of exposure and outcome variables, the use of advanced and appropriate statistical analyses and well-designed quasi-experimental studies would more accurately support the conclusions. Cluster randomized trials should be used whenever possible and appropriate, although the limitations of this approach should also be acknowledged. These issues are reviewed in this paper. We conclude that there are good research opportunities in the field of antibiotic stewardship. Copyright © 2013 Elsevier España, S.L. All rights reserved.

Synaptic clustering within dendrites: an emerging theory of memory formation

PubMed Central

Kastellakis, George; Cai, Denise J.; Mednick, Sara C.; Silva, Alcino J.; Poirazi, Panayiota

2015-01-01

It is generally accepted that complex memories are stored in distributed representations throughout the brain, however the mechanisms underlying these representations are not understood. Here, we review recent findings regarding the subcellular mechanisms implicated in memory formation, which provide evidence for a dendrite-centered theory of memory. Plasticity-related phenomena which affect synaptic properties, such as synaptic tagging and capture, synaptic clustering, branch strength potentiation and spinogenesis provide the foundation for a model of memory storage that relies heavily on processes operating at the dendrite level. The emerging picture suggests that clusters of functionally related synapses may serve as key computational and memory storage units in the brain. We discuss both experimental evidence and theoretical models that support this hypothesis and explore its advantages for neuronal function. PMID:25576663

A new look at Op art: towards a simple explanation of illusory motion.

PubMed

Zanker, Johannes M; Walker, Robin

2004-04-01

Vivid motion illusions created by some Op art paintings are at the centre of a lively scientific debate about possible mechanisms that might underlie these phenomena. Here we review emerging evidence from a new approach that combines perceptual judgements of the illusion and observations of eye movements with simulations of the induced optic flow. This work suggests that the small involuntary saccades which participants make when viewing such Op art patterns would generate an incoherent distribution of motion signals that resemble the perceptual effects experienced by the observers. The combined experimental and computational evidence supports the view that the illusion is indeed caused by involuntary image displacements picked up by low-level motion detectors, and further suggests that coherent motion signals are crucial to perceive a stable world.

A new look at Op art: towards a simple explanation of illusory motion

NASA Astrophysics Data System (ADS)

Zanker, Johannes M.; Walker, Robin

Vivid motion illusions created by some Op art paintings are at the centre of a lively scientific debate about possible mechanisms that might underlie these phenomena. Here we review emerging evidence from a new approach that combines perceptual judgements of the illusion and observations of eye movements with simulations of the induced optic flow. This work suggests that the small involuntary saccades which participants make when viewing such Op art patterns would generate an incoherent distribution of motion signals that resemble the perceptual effects experienced by the observers. The combined experimental and computational evidence supports the view that the illusion is indeed caused by involuntary image displacements picked up by low-level motion detectors, and further suggests that coherent motion signals are crucial to perceive a stable world.

Immunity and Inflammation in Epilepsy

PubMed Central

Vezzani, Annamaria; Lang, Bethan; Aronica, Eleonora

2016-01-01

This review reports the available evidence on the activation of the innate and adaptive branches of the immune system and the related inflammatory processes in epileptic disorders and the putative pathogenic role of inflammatory processes developing in the brain, as indicated by evidence from experimental and clinical research. Indeed, there is increasing knowledge supporting a role of specific inflammatory mediators and immune cells in the generation and recurrence of epileptic seizures, as well as in the associated neuropathology and comorbidities. Major challenges in this field remain: a better understanding of the key inflammatory pathogenic pathways activated in chronic epilepsy and during epileptogenesis, and how to counteract them efficiently without altering the homeostatic tissue repair function of inflammation. The relevance of this information for developing novel therapies will be highlighted. PMID:26684336

Dehalococcoides as a Potential Biomarker Evidence for Uncharacterized Organohalides in Environmental Samples

PubMed Central

Lu, Qihong; Yu, Ling; Liang, Zhiwei; Yan, Qingyun; He, Zhili; Luan, Tiangang; Liang, Dawei; Wang, Shanquan

2017-01-01

The massive production and improper disposal of organohalides resulted in worldwide contamination in soil and water. However, their environmental survey based on chromatographic methods was hindered by challenges in testing the extremely wide variety of organohalides. Dehalococcoides as obligate organohalide-respiring bacteria exclusively use organohalides as electron acceptors to support their growth, of which the presence could be coupled with organohalides and, therefore, could be employed as a biomarker of the organohalide pollution. In this study, Dehalococcoides was screened in various samples of bioreactors and subsurface environments, showing the wide distribution of Dehalococcoides in sludge and sediment. Further laboratory cultivation confirmed the dechlorination activities of those Dehalococcoides. Among those samples, Dehalococcoides accounting for 1.8% of the total microbial community was found in an anaerobic granular sludge sample collected from a full-scale bioreactor treating petroleum wastewater. Experimental evidence suggested that the influent wastewater in the bioreactor contained bromomethane which support the growth of Dehalococcoides. This study demonstrated that Dehalococcoides could be employed as a promising biomarker to test the present of organohalides in wastestreams or other environmental samples. PMID:28919889

Cardiovascular Protective Effects and Clinical Applications of Resveratrol.

PubMed

Cho, Sanghyun; Namkoong, Kyung; Shin, Minji; Park, Jueun; Yang, Eunyeong; Ihm, Jinsoo; Thu, Vu Thi; Kim, Hyoung Kyu; Han, Jin

2017-04-01

Resveratrol is a naturally occurring phenol that is generated by plant species following injury or attack by bacterial and fungal pathogens. This compound was first described as the French Paradox in 1992. Later in 2003, resveratrol was reported to activate sirtuins in yeast cells. Recent experimental studies have found that resveratrol offers a variety of benefits that include both anticarcinogenic and anti-inflammatory effects in addition to the ability to reverse obesity, attenuate hyperglycemia and hyperinsulinemia, protect heart and endothelial function, and increase the life span. Multiple molecular targets are associated with the cardioprotective capabilities of resveratrol, and therefore, resveratrol has potential for a wide range of new therapeutic strategies for atherosclerosis, ischemia/reperfusion, metabolic syndrome, cardiac failure, and inflammatory alterations during aging. Expectations for application in human patients, however, suffer from a lack of sufficient clinical evidence in support of these beneficial effects. This article reviews recently reported basic research results that describe the beneficial effects of resveratrol in an attempt to condense the evidence observed in clinical trials and provide support for the future development of novel clinical therapeutics in patients with cardiovascular diseases.

Epidemiological criteria for evidence of beneficial or adverse effects of elevated dosages of vitamins.

PubMed

Bruppacher, R

1989-01-01

Criteria for epidemiological evidence of effects of elevated dosages of vitamins are basically the same as those for the evidence of effects of other exposures. Given the unambiguous classifications of both exposure and cases, they comprise strength, significance, specificity, and consistency of the statistical association, plausible time relationship as well as dose-effect relationship and consistency with other evidence. Today, the term epidemiological evidence usually refers to field experience, often to "observational," i.e., non-experimental, evidence. An extreme example for this are the so-called "ecological studies," which are frequently criticized because of their potential for exaggerated interpretations, though they can be very helpful in constructing and supporting hypotheses. For very rare and long-term effects the description and evaluation of individual cases are often combined with attempts of quantification, by relating them to the estimated exposure of the source population. This is subject to numerous sources of errors. If it is difficult to confirm the existence of rare and late effects, as the collection and interpretation of data on the prevention of such effects often present almost insurmountable methodological challenges. However, with correct interpretation and by keeping the quantitative perspective in mind, epidemiological evidence can be extremely helpful in the assessment of the overall importance, i.e., the public health significance, of such effects.

20 CFR 219.57 - Evidence of a parent's support.

Code of Federal Regulations, 2010 CFR

2010-04-01

... 20 Employees' Benefits 1 2010-04-01 2010-04-01 false Evidence of a parent's support. 219.57... EVIDENCE REQUIRED FOR PAYMENT Other Evidence Requirements § 219.57 Evidence of a parent's support. (a) The Board will require the parent's signed statement showing his or her income, any other sources of support...

Non-transcriptional interactions of Hox proteins: inventory, facts, and future directions.

PubMed

Rezsohazy, René

2014-01-01

Hox proteins are conserved homeodomain transcription factors involved in the control of embryo patterning, organ development, and cell differentiation during animal development and adult life. Although recognizably active in gene regulation, accumulating reports support that Hox proteins are also active in controlling other molecular processes like mRNA translation, DNA repair, initiation of DNA replication, and possibly modulation of signal transduction. Here we review experimental evidence as well as databases entries indicative of non-transcriptional activities of Hox proteins. Copyright © 2013 Wiley Periodicals, Inc.

What motivates participation in violent political action: selective incentives or parochial altruism?

PubMed

Ginges, Jeremy; Atran, Scott

2009-06-01

In standard models of decision making, participation in violent political action is understood as the product of instrumentally rational reasoning. According to this line of thinking, instrumentally rational individuals will participate in violent political action only if there are selective incentives that are limited to participants. We argue in favor of an alternate model of political violence where participants are motivated by moral commitments to collective sacred values. Correlative and experimental empirical evidence in the context of the Israeli-Palestinian conflict strongly supports this alternate view.

Studies on conducting nanocomposite with gallium nitride-doped ferrite, part - III wasp-waist formation

NASA Astrophysics Data System (ADS)

Indrakanti, Rajani; Rao, V. Brahmaji; Kiran, C. Udaya

2018-05-01

We report the maiden experimental observation of the formation of Wasp-waists in the Hysteresis loop, of PPY Nanocomposite with GaN doped Ferrite. Earlier this phenomenon was reported in paleo magnetic and environmental magnetic studies. It is probably the very first time we report it in our Synthesized Nanocomposites. Details supported by data are presented. Parameters like Exchange Anisotropy, Multi Domain formation, Variations in Coercivity are suspected to be prominent causes for this occurrence. Systematic analysis of our data provides substantial evidence for the existence of the phenomenon.

Global instability in a laminar boundary layer perturbed by an isolated roughness element

NASA Astrophysics Data System (ADS)

Puckert, Dominik K.; Rist, Ulrich

2018-03-01

Roughness-induced boundary-layer instabilities are investigated by means of hot-film anemometry in a water channel to provide experimental evidence of a global instability. It is shown that the roughness wake dynamics depends on extrinsic disturbances (amplifier) at subcritical Reynolds numbers, whereas intrinsic, self-sustained oscillations (wavemaker) are suspected at supercritical Reynolds numbers. The critical Reynolds number, therefore, separates between two different instability mechanisms. Furthermore, the critical Reynolds number from recent theoretical results is successfully confirmed in this experiment, supporting the physical relevance of 3-d global stability theory.

Seeing in context. Comment on "Seeing mental states: An experimental strategy for measuring the observability of other minds" by Cristina Becchio et al.

NASA Astrophysics Data System (ADS)

Gallagher, Shaun

2018-03-01

Becchio et al. [1] address questions about direct social perception in the context of interacting with others. In regard to social cognition the claim that we can see mental states is the subject of ongoing debate. Becchio et al. [2,3] have produced some of the best empirical evidence in support of this claim. In explicating and clarifying their methodology Becchio's group is clearly advancing the field and sketching a way to settle the debate.

Theoretical study of piezo-phototronic nano-LEDs.

PubMed

Liu, Ying; Niu, Simiao; Yang, Qing; Klein, Benjamin D B; Zhou, Yu Sheng; Wang, Zhong Lin

2014-11-12

Two-dimensional finite-element simulation of the piezo-phototronic effect in p-n-junction-based devices is carried out for the first time. A charge channel can be induced at the p-n junction interface when strain is applied, given the n-side is a piezoelectric semiconductor and the p-type side is non-piezoelectric semiconductor. This provides the first simulated evidence supporting the previously suggested mechanism responsible for the experimentally observed gigantic change of light-emission efficiency in piezo-phototronic light-emitting devices. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Waterspout, Gust Fronts and Associated Cloud Systems

NASA Technical Reports Server (NTRS)

Simpson, J.

1983-01-01

Nine waterspouts observed on five experimental days during the GATE period of observations are discussed. Primary data used are from 2 aircraft flying in different patterns, one above the other between 30 and 300 m. There is strong evidence associating whirl initiation with cumulus outflow. Computations prepared from estimates of convergence with the region suggest the possibility of vortex generation within 4 minutes. This analysis supports (1) the importance cumulus outflows may have in waterspout initiation and (2) the possibility that sea surface temperature gradients may be important in enabling waterspout development from modest size cumuli.

Film viewing conditions in mammography.

PubMed

Hill, S J; Faulkner, K; Law, J; Starritt, H C

1997-04-01

A requirement for a minimum viewing box brightness of 3000 cd m-2 for reading mammograms has been widely advocated. Some recent work has challenged that opinion by reporting no significant variation in visibility of low contrast and fine detail objects over a wide range of brightness levels. This paper provides further experimental evidence to support the latter conclusion, at least over the range 1340-4190 cd m-2, and suggests that the currently recommended minimum viewing box brightness levels need to be revised. The importance of reducing room lighting levels is fully confirmed.

Circularly polarized luminescence of syndiotactic polystyrene

NASA Astrophysics Data System (ADS)

Rizzo, Paola; Abbate, Sergio; Longhi, Giovanna; Guerra, Gaetano

2017-11-01

Syndiotactic polystyrene (s-PS) films, when crystallized from the amorphous state by temporary sorption of non-racemic guest molecules (like carvone) not only exhibit unusually high optical activity, both in the UV-Visible and Infrared ranges, but also present circularly polarized luminescence (CPL) with high dissymmetry ratios (g = ΔI/I values in the range 0.02-0.03). Experimental evidences provide support, rather than to the usual molecular circular dichroism, to a supramolecular chiral optical response being extrinsic to the site of photon absorption and emission, possibly associated with a helical morphology of s-PS crystallites.

The Epileptic Thalamocortical Network is a Macroscopic Self-Sustained Oscillator: Evidence from Frequency-Locking Experiments in Rat Brains

NASA Astrophysics Data System (ADS)

Velazquez, J. L. Perez; Erra, R. Guevara; Rosenblum, M.

2015-02-01

The rhythmic activity observed in nervous systems, in particular in epilepsies and Parkinson's disease, has often been hypothesized to originate from a macroscopic self-sustained neural oscillator. However, this assumption has not been tested experimentally. Here we support this viewpoint with in vivo experiments in a rodent model of absence seizures, by demonstrating frequency locking to external periodic stimuli and finding the characteristic Arnold tongue. This result has important consequences for developing methods for the control of brain activity, such as seizure cancellation.

Behavioral fever in ectothermic vertebrates.

PubMed

Rakus, Krzysztof; Ronsmans, Maygane; Vanderplasschen, Alain

2017-01-01

Fever is an evolutionary conserved defense mechanism which is present in both endothermic and ectothermic vertebrates. Ectotherms in response to infection can increase their body temperature by moving to warmer places. This process is known as behavioral fever. In this review, we summarize the current knowledge on the mechanisms of induction of fever in mammals. We further discuss the evolutionary conserved mechanisms existing between fever of mammals and behavioral fever of ectothermic vertebrates. Finally, the experimental evidences supporting an adaptive value of behavioral fever expressed by ectothermic vertebrates are summarized. Copyright © 2016 Elsevier Ltd. All rights reserved.

The role of partitioning of reagents in grafting and curing reactions initiated by ionizing radiation and UV

NASA Astrophysics Data System (ADS)

Chaplin, R. P.; Dworjanyn, P. A.; Gamage, N. J. W.; Garnett, J. L.; Jankiewicz, S. V.; Khan, M. A.; Sangster, D. F.

1996-03-01

Experimental evidence involving monomer absorption studies using tritiated styrene is shown to support the proposal that additives such as mineral acids and certain inorganic salts when dissolved in the monomer solution enhance radiation grafting yields by a mechanism involving partitioning of reagents. Photoinitiators such as benzoin ethyl ether and its methyl analogue are reported as new additives for grafting of styrene in methanol to cellulose and polypropylene initiated by ionizing radiation. The partitioning concept is shown to be relevant in analogous UV grafting and curing processes.

Small fragment wounds: biophysics, pathophysiology and principles of management.

PubMed

Hill, P F; Edwards, D P; Bowyer, G W

2001-02-01

Military surgical doctrine has traditionally taught that all ballistic wounds should be formally managed by surgical intervention. There is now, however, both experimental and clinical evidence supporting the nonoperative treatment of selected small fragment wounds. Low energy-transfer wounds affecting the soft tissues, without neuro-vascular compromise and with stable fracture patterns, may be suitable for early antibiotic treatment. The management of ballistic wounds to the gastrointestinal tract requires surgical intervention but, advances in the treatment of these wounds, especially those involving the colon, may allow more effective treatment with a reduced morbidity.

Supplementary feeding restructures urban bird communities

PubMed Central

Galbraith, Josie A.; Jones, Darryl N.; Stanley, Margaret C.

2015-01-01

Food availability is a primary driver of avian population regulation. However, few studies have considered the effects of what is essentially a massive supplementary feeding experiment: the practice of wild bird feeding. Bird feeding has been posited as an important factor influencing the structure of bird communities, especially in urban areas, although experimental evidence to support this is almost entirely lacking. We carried out an 18-mo experimental feeding study at 23 residential properties to investigate the effects of bird feeding on local urban avian assemblages. Our feeding regime was based on predominant urban feeding practices in our region. We used monthly bird surveys to compare avian community composition, species richness, and the densities of local species at feeding and nonfeeding properties. Avian community structure diverged at feeding properties and five of the commonest garden bird species were affected by the experimental feeding regime. Introduced birds particularly benefitted, with dramatic increases observed in the abundances of house sparrow (Passer domesticus) and spotted dove (Streptopelia chinensis) in particular. We also found evidence of a negative effect on the abundance of a native insectivore, the grey warbler (Gerygone igata). Almost all of the observed changes did not persist once feeding had ceased. Our study directly demonstrates that the human pastime of bird feeding substantially contributes to the structure of avian community in urban areas, potentially altering the balance between native and introduced species. PMID:25941361

Chapter 8. Tea and Cancer Prevention: Epidemiological Studies

PubMed Central

Yuan, Jian-Min; Sun, Canlan; Butler, Lesley M.

2011-01-01

Experimental studies have consistently shown the inhibitory activities of tea extracts on tumorigenesis in multiple model systems. Epidemiologic studies, however, have produced inconclusive results in humans. A comprehensive review was conducted to assess the current knowledge on tea consumption and risk of cancers in humans. In general, consumption of black tea was not associated with lower risk of cancer. High intake of green tea was consistently associated with reduced risk of upper gastrointestinal tract cancers after sufficient control for confounders. Limited data support a protective effect of green tea on lung and hepatocellular carcinogenesis. Although observational studies do not support a beneficial role of tea intake on prostate cancer risk, phase II clinical trials have demonstrated an inhibitory effect of green tea extract against the progression of prostate pre-malignant lesions. Green tea may exert beneficial effects against mammary carcinogenesis in premenopausal women and recurrence of breast cancer. There is no sufficient evidence that supports a protective role of tea intake on the development of cancers of the colorectum, pancreas, urinary tract, glioma, lymphoma, and leukemia. Future prospective observational studies with biomarkers of exposure and phase III clinical trials are required to provide definitive evidence for the hypothesized beneficial effect of tea consumption on cancer formation in humans. PMID:21419224

eHealth in the future of medications management: personalisation, monitoring and adherence.

PubMed

Car, Josip; Tan, Woan Shin; Huang, Zhilian; Sloot, Peter; Franklin, Bryony Dean

2017-04-05

Globally, healthcare systems face major challenges with medicines management and medication adherence. Medication adherence determines medication effectiveness and can be the single most effective intervention for improving health outcomes. In anticipation of growth in eHealth interventions worldwide, we explore the role of eHealth in the patients' medicines management journey in primary care, focusing on personalisation and intelligent monitoring for greater adherence. eHealth offers opportunities to transform every step of the patient's medicines management journey. From booking appointments, consultation with a healthcare professional, decision-making, medication dispensing, carer support, information acquisition and monitoring, to learning about medicines and their management in daily life. It has the potential to support personalisation and monitoring and thus lead to better adherence. For some of these dimensions, such as supporting decision-making and providing reminders and prompts, evidence is stronger, but for many others more rigorous research is urgently needed. Given the potential benefits and barriers to eHealth in medicines management, a fine balance needs to be established between evidence-based integration of technologies and constructive experimentation that could lead to a game-changing breakthrough. A concerted, transdisciplinary approach adapted to different contexts, including low- and middle-income contries is required to realise the benefits of eHealth at scale.

Neurolinguistic programming: a systematic review of the effects on health outcomes.

PubMed

Sturt, Jackie; Ali, Saima; Robertson, Wendy; Metcalfe, David; Grove, Amy; Bourne, Claire; Bridle, Chris

2012-11-01

Neurolinguistic programming (NLP) in health care has captured the interest of doctors, healthcare professionals, and managers. To evaluate the effects of NLP on health-related outcomes. Systematic review of experimental studies. The following data sources were searched: MEDLINE, PsycINFO, ASSIA, AMED, CINAHL, Web of Knowledge, CENTRAL, NLP specialist databases, reference lists, review articles, and NLP professional associations, training providers, and research groups. Searches revealed 1459 titles from which 10 experimental studies were included. Five studies were randomised controlled trials (RCTs) and five were pre-post studies. Targeted health conditions were anxiety disorders, weight maintenance, morning sickness, substance misuse, and claustrophobia during MRI scanning. NLP interventions were mainly delivered across 4-20 sessions although three were single session. Eighteen outcomes were reported and the RCT sample sizes ranged from 22 to 106. Four RCTs reported no significant between group differences with the fifth finding in favour of the NLP arm (F = 8.114, P<0.001). Three RCTs and five pre-post studies reported within group improvements. Risk of bias across all studies was high or uncertain. There is little evidence that NLP interventions improve health-related outcomes. This conclusion reflects the limited quantity and quality of NLP research, rather than robust evidence of no effect. There is currently insufficient evidence to support the allocation of NHS resources to NLP activities outside of research purposes.

Orosensory and Homeostatic Functions of the Insular Taste Cortex.

PubMed

de Araujo, Ivan E; Geha, Paul; Small, Dana M

2012-03-01

The gustatory aspect of the insular cortex is part of the brain circuit that controls ingestive behaviors based on chemosensory inputs. However, the sensory properties of foods are not restricted to taste and should also include salient features such as odor, texture, temperature, and appearance. Therefore, it is reasonable to hypothesize that specialized circuits within the central taste pathways must be involved in representing several other oral sensory modalities in addition to taste. In this review, we evaluate current evidence indicating that the insular gustatory cortex functions as an integrative circuit, with taste-responsive regions also showing heightened sensitivity to olfactory, somatosensory, and even visual stimulation. We also review evidence for modulation of taste-responsive insular areas by changes in physiological state, with taste-elicited neuronal responses varying according to the nutritional state of the organism. We then examine experimental support for a functional map within the insular cortex that might reflect the various sensory and homeostatic roles associated with this region. Finally, we evaluate the potential role of the taste insular cortex in weight-gain susceptibility. Taken together, the current experimental evidence favors the view that the insular gustatory cortex functions as an orosensory integrative system that not only enables the formation of complex flavor representations but also mediates their modulation by the internal state of the body, playing therefore a central role in food intake regulation.

Evaluation of the reported association of obsessive-compulsive symptoms or disorder with Tourette's disorder.

PubMed

Shapiro, A K; Shapiro, E

1992-01-01

This review evaluates the evidence reporting an association of obsessive-compulsive symptoms (OCS) and obsessive-compulsive disorder (OCD) with Tourette's syndrome or disorder (TS). Published reports in the literature describing a relationship between OCS-OCD and TS provided the data for the review. The methodological adequacy of the studies are discussed and rated on five criteria: adequacy of the experimental sample, presence and adequacy of the control sample, whether tics are defined as OCS-OCD, whether blind procedures are used to diagnose OCS-OCD in subjects and controls, and evidence for the reliability and validity of OCS-OCD measures. Although there are considerable clinical indications suggesting an association of OCS-OCD with TS and chronic motor tic disorder (CMT), and a possible overlap between OSC-OCD and TS, our evaluation of the evidence does not provide adequate support for an association between these disorders. To meaningfully evaluate the possible relationship between OCS-OCD and TS requires development of specific criteria for classification of OCS-OCD-TS symptoms, use of adequate experimental and control samples, blind evaluation, reliable and valid measures of OCS-OCD-TS, and appropriate statistical analysis. If such studies are performed, it is possible that the strong relationship reported between OCS-OCD and TS is more likely to be artifact than fact, and recent bandwagon effect rather than the latest breakthrough.

Blobel and Sabatini's "Beautiful Idea": Visual Representations of the Conception and Refinement of the Signal Hypothesis.

PubMed

LaBonte, Michelle Lynne

2017-11-01

In 1971, Günter Blobel and David Sabatini proposed a novel and quite speculative schematic model to describe how proteins might reach the proper cellular location. According to their proposal, proteins destined to be secreted from the cell contain a "signal" to direct their release. Despite the fact that Blobel and Sabatini presented their signal hypothesis as a "beautiful idea" not grounded in experimental evidence, they received criticism from other scientists who opposed such speculation. Following the publication of the 1971 model, Blobel persisted in conducting experiments and revising the model to incorporate new data. In fact, over the period of 1975-1984, Blobel and colleagues published five subsequent schematic models of the signal hypothesis, each revised based on new laboratory evidence. I propose that the original 1971 model can be viewed as an epistemic creation. Additionally, analysis of the subsequent schematic diagrams over the period of 1975-1984 allows one to track Blobel's changing conception of an epistemic object over time. Furthermore, the entire series of schematic diagrams presented by Blobel from 1971 to 1984 allow one to visualize the initial conception and subsequent reworking of a scientific theory. In 1999, Blobel was awarded the Nobel Prize in Physiology or Medicine for his work on the signal hypothesis, which was ultimately supported by experimental evidence gathered after the speculative model was published.

Neurolinguistic programming: a systematic review of the effects on health outcomes

PubMed Central

Sturt, Jackie; Ali, Saima; Robertson, Wendy; Metcalfe, David; Grove, Amy; Bourne, Claire; Bridle, Chris

2012-01-01

Background Neurolinguistic programming (NLP) in health care has captured the interest of doctors, healthcare professionals, and managers. Aim To evaluate the effects of NLP on health-related outcomes. Design and setting Systematic review of experimental studies. Method The following data sources were searched: MEDLINE®, PsycINFO, ASSIA, AMED, CINAHL®, Web of Knowledge, CENTRAL, NLP specialist databases, reference lists, review articles, and NLP professional associations, training providers, and research groups. Results Searches revealed 1459 titles from which 10 experimental studies were included. Five studies were randomised controlled trials (RCTs) and five were pre-post studies. Targeted health conditions were anxiety disorders, weight maintenance, morning sickness, substance misuse, and claustrophobia during MRI scanning. NLP interventions were mainly delivered across 4–20 sessions although three were single session. Eighteen outcomes were reported and the RCT sample sizes ranged from 22 to 106. Four RCTs reported no significant between group differences with the fifth finding in favour of the NLP arm (F = 8.114, P<0.001). Three RCTs and five pre-post studies reported within group improvements. Risk of bias across all studies was high or uncertain. Conclusion There is little evidence that NLP interventions improve health-related outcomes. This conclusion reflects the limited quantity and quality of NLP research, rather than robust evidence of no effect. There is currently insufficient evidence to support the allocation of NHS resources to NLP activities outside of research purposes. PMID:23211179

When Genomics Is Not Enough: Experimental Evidence for a Decrease in LINE-1 Activity During the Evolution of Australian Marsupials

PubMed Central

Gallus, Susanne; Lammers, Fritjof

2016-01-01

The autonomous transposable element LINE-1 is a highly abundant element that makes up between 15% and 20% of therian mammal genomes. Since their origin before the divergence of marsupials and placental mammals, LINE-1 elements have contributed actively to the genome landscape. A previous in silico screen of the Tasmanian devil genome revealed a lack of functional coding LINE-1 sequences. In this study we present the results of an in vitro analysis from a partial LINE-1 reverse transcriptase coding sequence in five marsupial species. Our experimental screen supports the in silico findings of the genome-wide degradation of LINE-1 sequences in the Tasmanian devil, and identifies a high frequency of degraded LINE-1 sequences in other Australian marsupials. The comparison between the experimentally obtained LINE-1 sequences and reference genome assemblies suggests that conclusions from in silico analyses of retrotransposition activity can be influenced by incomplete genome assemblies from short reads. PMID:27389686

A critical review on tablet disintegration.

PubMed

Quodbach, Julian; Kleinebudde, Peter

2016-09-01

Tablet disintegration is an important factor for drug release and can be modified with excipients called tablet disintegrants. Tablet disintegrants act via different mechanisms and the efficacy of these excipients is influenced by various factors. In this review, the existing literature on tablet disintegration is critically reviewed. Potential disintegration mechanisms, as well as impact factors on the disintegration process will be discussed based on experimental evidence. Search terms for Scopus and Web of Science included "tablet disintegration", "mechanism tablet disintegration", "superdisintegrants", "disintegrants", "swelling force", "disintegration force", "disintegration mechanisms", as well as brand names of commonly applied superdisintegrants. References of identified papers were screened as well. Experimental data supports swelling and shape recovery as main mechanisms of action of disintegrants. Other tablet excipients and different manufacturing techniques greatly influence the disintegration process. The use of different excipients, experimental setups and manufacturing techniques, as well as the demand for original research led to a distinct patchwork of knowledge. Broader, more systematic approaches are necessary not only to structure the past but also future findings.

Social learning by orangutans (Pongo abelii and Pongo pygmaeus) in a simulated food-processing task.

PubMed

Stoinski, Tara S; Whiten, Andrew

2003-09-01

Increasing evidence for behavioral differences between populations of primates has created a resurgence of interest in examining mechanisms of information transfer between individuals. The authors examined the social transmission of information in 15 captive orangutans (Pongo abelii and Pongo pygmaeus) using a simulated food-processing task. Experimental subjects were shown 1 of 2 methods for removing a suite of defenses on an "artificial fruit." Control subjects were given no prior exposure before interacting with the fruit. Observing a model provided a functional advantage in the task, as significantly more experimental than control subjects opened the fruit. Within the experimental groups, the authors found a trend toward differences in the actual behaviors used to remove 1 of the defenses. Results support observations from the wild implying horizontal transfer of information in orangutans and show that a number of social learning processes are likely to be involved in the transfer of knowledge in this species. Copyright 2003 APA, all rights reserved

FT-IR spectroscopy combined with DFT calculation to explore solvent effects of vinyl acetate

NASA Astrophysics Data System (ADS)

Chen, Yi; Zhang, Hui; Liu, Qing

The infrared vibration frequencies of vinyl acetate (VAc) in 18 different solvents were theoretically computed at Density Function Theory (DFT) B3LYP/6-311G* level based on Polarizable Continuum Model (PCM) and experimentally recorded by FT-IR spectroscopy. The solvent-induced long-range bulk electrostatic solvation free energies of VAc (ΔGelec) were calculated by the SMD model. The Cdbnd O stretching vibration frequencies of VAc were utilized as a measure of the chemical reactivities of the Cdbnd C group in VAc. The calculated and experimental Cdbnd O stretching vibration frequencies of VAc (νcal(Cdbnd O) and νexp(Cdbnd O)) were correlated with empirical solvent parameters including the KBM equation, the Swain equation and the linear solvation energy relationships (LSER). Through ab initio calculation, assignments of the two Cdbnd O absorption bands of VAc in alcohol solvents were achieved. The PCM, SMD and ab initio calculation offered supporting evidence to explain the FT-IR experimental observations from differing aspects.

Experimental evidence and modelling of drought induced alternative stable soil moisture states

NASA Astrophysics Data System (ADS)

Robinson, David; Jones, Scott; Lebron, Inma; Reinsch, Sabine; Dominguez, Maria; Smith, Andrew; Marshal, Miles; Emmett, Bridget

2017-04-01

The theory of alternative stable states in ecosystems is well established in ecology; however, evidence from manipulation experiments supporting the theory is limited. Developing the evidence base is important because it has profound implications for ecosystem management. Here we show evidence of the existence of alternative stable soil moisture states induced by drought in an upland wet heath. We used a long-term (15 yrs) climate change manipulation experiment with moderate sustained drought, which reduced the ability of the soil to retain soil moisture by degrading the soil structure, reducing moisture retention. Moreover, natural intense droughts superimposed themselves on the experiment, causing an unexpected additional alternative soil moisture state to develop, both for the drought manipulation and control plots; this impaired the soil from rewetting in winter. Our results show the coexistence of three stable states. Using modelling with the Hydrus 1D software package we are able to show the circumstances under which shifts in soil moisture states are likely to occur. Given the new understanding it presents a challenge of how to incorporate feedbacks, particularly related to soil structure, into soil flow and transport models?

Periodontal bacterial invasion and infection: contribution to atherosclerotic pathology.

PubMed

Reyes, Leticia; Herrera, David; Kozarov, Emil; Roldán, Silvia; Progulske-Fox, Ann

2013-04-01

The objective of this review was to perform a systematic evaluation of the literature reporting current scientific evidence for periodontal bacteria as contributors to atherosclerosis. Literature from epidemiological, clinical and experimental studies concerning periodontal bacteria and atherosclerosis were reviewed. Gathered data were categorized into seven "proofs" of evidence that periodontal bacteria: 1) disseminate from the oral cavity and reach systemic vascular tissues; 2) can be found in the affected tissues; 3) live within the affected site; 4) invade affected cell types in vitro; 5) induce atherosclerosis in animal models of disease; 6) non-invasive mutants of periodontal bacteria cause significantly reduced pathology in vitro and in vivo; and 7) periodontal isolates from human atheromas can cause disease in animal models of infection. Substantial evidence for proofs 1 to 6 was found. However, proof 7 has not yet been fulfilled. Despite the lack of evidence that periodontal bacteria obtained from human atheromas can cause atherosclerosis in animal models of infection, attainment of proofs 1 to 6 provides support that periodontal pathogens can contribute to atherosclerosis. © 2013 European Federation of Periodontology and American Academy of Periodontology.

Neuroprotection in Experimental Autoimmune Encephalomyelitis and Progressive Multiple Sclerosis by Cannabis-Based Cannabinoids.

PubMed

Pryce, Gareth; Riddall, Dieter R; Selwood, David L; Giovannoni, Gavin; Baker, David

2015-06-01

Multiple sclerosis (MS) is the major immune-mediated, demyelinating, neurodegenerative disease of the central nervous system. Compounds within cannabis, notably Δ9-tetrahydrocannabinol (Δ9-THC) can limit the inappropriate neurotransmissions that cause MS-related problems and medicinal cannabis is now licenced for the treatment of MS symptoms. However, the biology indicates that the endocannabinoid system may offer the potential to control other aspects of disease. Although there is limited evidence that the cannabinoids from cannabis are having significant immunosuppressive activities that will influence relapsing autoimmunity, we and others can experimentally demonstrate that they may limit neurodegeneration that drives progressive disability. Here we show that synthetic cannabidiol can slow down the accumulation of disability from the inflammatory penumbra during relapsing experimental autoimmune encephalomyelitis (EAE) in ABH mice, possibly via blockade of voltage-gated sodium channels. In addition, whilst non-sedating doses of Δ9-THC do not inhibit relapsing autoimmunity, they dose-dependently inhibit the accumulation of disability during EAE. They also appear to slow down clinical progression during MS in humans. Although a 3 year, phase III clinical trial did not detect a beneficial effect of oral Δ9-THC in progressive MS, a planned subgroup analysis of people with less disability who progressed more rapidly, demonstrated a significant slowing of progression by oral Δ9-THC compared to placebo. Whilst this may support the experimental and biological evidence for a neuroprotective effect by the endocannabinoid system in MS, it remains to be established whether this will be formally demonstrated in further trials of Δ9-THC/cannabis in progressive MS.

Overstated evidence for short-term effects of violent games on affect and behavior: A reanalysis of Anderson et al. (2010).

PubMed

Hilgard, Joseph; Engelhardt, Christopher R; Rouder, Jeffrey N

2017-07-01

Violent video games are theorized to be a significant cause of aggressive thoughts, feelings, and behaviors. Important evidence for this claim comes from a large meta-analysis by Anderson and colleagues (2010), who found effects of violent games in experimental, cross-sectional, and longitudinal research. In that meta-analysis, the authors argued that there is little publication or analytic bias in the literature, an argument supported by their use of the trim-and-fill procedure. In the present manuscript, we reexamine their meta-analysis using a wider array of techniques for detecting bias and adjusting effect sizes. Our conclusions differ from those of Anderson and colleagues in 3 salient ways. First, we detect substantial publication bias in experimental research on the effects of violent games on aggressive affect and aggressive behavior. Second, after adjustment for bias, the effects of violent games on aggressive behavior in experimental research are estimated as being very small, and estimates of effects on aggressive affect are much reduced. In contrast, the cross-sectional literature finds correlations that appear largely unbiased. Third, experiments meeting the original authors' criteria for methodological quality do not yield larger adjusted effects than other experiments, but instead yield larger indications of bias, indicating that perhaps they were selected for significance. We outline future directions for stronger experimental research. The results indicate the need for an open, transparent, and preregistered research process to test the existence of the basic phenomenon. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

Plain packaging of cigarettes: do we have sufficient evidence?

PubMed Central

Smith, Collin N; Kraemer, John D; Johnson, Andrea C; Mays, Darren

2015-01-01

Tobacco industry marketing is a primary factor influencing cigarette smoking behavior and the cigarette pack has become an important marketing vehicle for tobacco companies. Standardized “plain” cigarette packaging is advocated as a public health policy to prevent and reduce morbidity and mortality caused by smoking by reducing youth smoking initiation and promoting cessation among smokers. Plain packaging was implemented in Australia in December 2012, and several other countries are considering doing so, but each faces foreseeable legal resistance from opponents to such measures. Tobacco companies have challenged these public health policies, citing international trade agreements and intellectual property laws. Decision-making in these court cases will hinge in part on whether the evidence indicates the public health benefits of plain packaging outweigh any potential harm to tobacco manufacturers’ interests. We reviewed the available evidence in support of plain packaging, finding evidence from observational, experimental, and population-based studies. Results indicate that plain packaging can reduce positive perceptions of smoking and dissuade tobacco use. Governments deciding to implement plain cigarette packaging measures can rely on this evidence to help make a strong case that plain packaging plays an important role in the context of comprehensive smoking prevention efforts. PMID:25897269

Effectiveness and safety of nutritional supplements in the treatment of hereditary retinal dystrophies: a systematic review

PubMed Central

Brito-García, N; del Pino-Sedeño, T; Trujillo-Martín, M M; Coco, R M; Rodríguez de la Rúa, E; del Cura-González, I; Serrano-Aguilar, P

2017-01-01

The hereditary retinal dystrophies (HRDs) are a group of genetically determined disorders that result in loss of the visual function. There is a lack of standard pharmacological treatments or widely accepted nutritional recommendations. The objective of this review is to summarise the scientific evidence on the effectiveness and safety of nutritional supplements for the treatment of HRDs. We conducted a scientific literature search on Medline and PreMedline, EMBASE, SCI-EXPANDED, SSCI, and The Cochrane Library up to August 2014. Experimental, quasi-experimental and controlled observational studies were selected. Eight studies were ultimately included, seven on retinitis pigmentosa (RP) and one on Best disease. Vitamin A, vitamin E, docosahexaenoic acid (DHA), lutein and β-carotene were assessed. A 15 000 IU daily dose of vitamin A was reported to have shown a small protective effect on the progression of RP, as was the use of the carotenoids lutein and β-carotene. Different DHA doses has no effect on RP or Best disease. No supplement showed severe adverse effects in the selected studies although strong evidence of toxicity exists for high doses of vitamin A and β-carotene in certain populations. The selected studies concluded that there may be a small beneficial effect of vitamin A, lutein and β-carotene on the progression of RP. The limited evidence available indicates some well-designed additional studies on combined supplements strategies may achieve more robust conclusions. Moreover, the scarcity of evidence available on the treatment of HRD other than RP with nutritional supplements supports the need for further research efforts. PMID:27935602

Ocean warming and spread of pathogenic vibrios in the aquatic environment.

PubMed

Vezzulli, Luigi; Colwell, Rita R; Pruzzo, Carla

2013-05-01

Vibrios are among the most common bacteria that inhabit surface waters throughout the world and are responsible for a number of severe infections both in humans and animals. Several reports recently showed that human Vibrio illnesses are increasing worldwide including fatal acute diarrheal diseases, such as cholera, gastroenteritis, wound infections, and septicemia. Many scientists believe this increase may be associated with global warming and rise in sea surface temperature (SST), although not enough evidence is available to support a causal link between emergence of Vibrio infections and climate warming. The effect of increased SST in promoting spread of vibrios in coastal and brackish waters is considered a causal factor explaining this trend. Field and laboratory studies carried out over the past 40 years supported this hypothesis, clearly showing temperature promotes Vibrio growth and persistence in the aquatic environment. Most recently, a long-term retrospective microbiological study carried out in the coastal waters of the southern North Sea provided the first experimental evidence for a positive and significant relationship between SST and Vibrio occurrence over a multidecadal time scale. As a future challenge, macroecological studies of the effects of ocean warming on Vibrio persistence and spread in the aquatic environment over large spatial and temporal scales would conclusively support evidence acquired to date combined with studies of the impact of global warming on epidemiologically relevant variables, such as host susceptibility and exposure. Assessing a causal link between ongoing climate change and enhanced growth and spread of vibrios and related illness is expected to improve forecast and mitigate future outbreaks associated with these pathogens.

Quasi-experimental study designs series-paper 4: uses and value.

PubMed

Bärnighausen, Till; Tugwell, Peter; Røttingen, John-Arne; Shemilt, Ian; Rockers, Peter; Geldsetzer, Pascal; Lavis, John; Grimshaw, Jeremy; Daniels, Karen; Brown, Annette; Bor, Jacob; Tanner, Jeffery; Rashidian, Arash; Barreto, Mauricio; Vollmer, Sebastian; Atun, Rifat

2017-09-01

Quasi-experimental studies are increasingly used to establish causal relationships in epidemiology and health systems research. Quasi-experimental studies offer important opportunities to increase and improve evidence on causal effects: (1) they can generate causal evidence when randomized controlled trials are impossible; (2) they typically generate causal evidence with a high degree of external validity; (3) they avoid the threats to internal validity that arise when participants in nonblinded experiments change their behavior in response to the experimental assignment to either intervention or control arm (such as compensatory rivalry or resentful demoralization); (4) they are often well suited to generate causal evidence on long-term health outcomes of an intervention, as well as nonhealth outcomes such as economic and social consequences; and (5) they can often generate evidence faster and at lower cost than experiments and other intervention studies. Copyright © 2017 Elsevier Inc. All rights reserved.

Does Exercise Improve Cognitive Performance? A Conservative Message from Lord's Paradox.

PubMed

Liu, Sicong; Lebeau, Jean-Charles; Tenenbaum, Gershon

2016-01-01

Although extant meta-analyses support the notion that exercise results in cognitive performance enhancement, methodology shortcomings are noted among primary evidence. The present study examined relevant randomized controlled trials (RCTs) published in the past 20 years (1996-2015) for methodological concerns arise from Lord's paradox. Our analysis revealed that RCTs supporting the positive effect of exercise on cognition are likely to include Type I Error(s). This result can be attributed to the use of gain score analysis on pretest-posttest data as well as the presence of control group superiority over the exercise group on baseline cognitive measures. To improve accuracy of causal inferences in this area, analysis of covariance on pretest-posttest data is recommended under the assumption of group equivalence. Important experimental procedures are discussed to maintain group equivalence.

Magnetic correlates in electromagnetic consciousness.

PubMed

Liboff, A R

2016-01-01

We examine the hypothesis that consciousness is a manifestation of the electromagnetic field, finding supportive factors not previously considered. It is not likely that traditional electrophysiological signaling modes can be readily transmitted throughout the brain to properly enable this field because of electric field screening arising from the ubiquitous distribution of high dielectric lipid membranes, a problem that vanishes for low-frequency magnetic fields. Many reports over the last few decades have provided evidence that living tissue is robustly sensitive to ultrasmall (1-100 nT) ELF magnetic fields overlapping the γ-frequency range often associated with awareness. An example taken from animal behavior (coherent bird flocking) lends support to the possibility of a disembodied electromagnetic consciousness. In contrast to quantum consciousness hypotheses, the present approach is open to experimental trial.

Combining Gene and Stem Cell Therapy for Peripheral Nerve Tissue Engineering.

PubMed

Busuttil, Francesca; Rahim, Ahad A; Phillips, James B

2017-02-15

Despite a substantially increased understanding of neuropathophysiology, insufficient functional recovery after peripheral nerve injury remains a significant clinical challenge. Nerve regeneration following injury is dependent on Schwann cells, the supporting cells in the peripheral nervous system. Following nerve injury, Schwann cells adopt a proregenerative phenotype, which supports and guides regenerating nerves. However, this phenotype may not persist long enough to ensure functional recovery. Tissue-engineered nerve repair devices containing therapeutic cells that maintain the appropriate phenotype may help enhance nerve regeneration. The combination of gene and cell therapy is an emerging experimental strategy that seeks to provide the optimal environment for axonal regeneration and reestablishment of functional circuits. This review aims to summarize current preclinical evidence with potential for future translation from bench to bedside.

PREditOR: a synthetic biology approach to removing heterochromatin from cells.

PubMed

Molina, Oscar; Carmena, Mar; Maudlin, Isabella E; Earnshaw, William C

2016-12-01

It is widely accepted that heterochromatin is necessary to maintain genomic stability. However, direct experimental evidence supporting this is slim. Previous studies using either enzyme inhibitors, gene knockout or knockdown studies all are subject to the caveat that drugs may have off-target effects and enzymes that modify chromatin proteins to support heterochromatin formation may also have numerous other cellular targets as well. Here, we describe PREditOR (protein reading and editing of residues), a synthetic biology approach that allows us to directly remove heterochromatin from cells without either drugs or global interference with gene function. We find that removal of heterochromatin perturbs mitotic progression and causes a dramatic increase in chromosome segregation defects, possibly as a result of interfering with the normal centromeric localization of the chromosomal passenger complex.

Unusual folded structures for a tethered squaraine-cholesterol derivative in Langmuir-Blodgett films

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

Stanescu, M.; Samha, H.; Perlstein, J.

2000-01-11

A squaraine-cholesterol diad, 1, which has been found to be a good gelator, has been studied in films at the air-water interface and in supported Langmuir-Blodgett films. Both experimental observations and simulations are consistent with a low-energy folded structure in which there are attractive noncovalent interactions between the squaraine chromophore and the steroid. Although different structures seem likely for 1 in both the crystal and organogels, the present studies suggest that the folded structure exists in both uncompressed and compressed films at the air-water interface and in supported LB films. In both environments the squaraine chromophore shows evidence of squaraine-squarainemore » aggregation; both J and H aggregates are indicated depending upon the conditions imposed upon the film.« less

Experimental hypervigilance changes the intensity/unpleasantness ratio of pressure sensations: evidence for the generalized hypervigilance hypothesis.

PubMed

Hollins, Mark; Walters, Sloan

2016-06-01

Patients with chronic pain conditions such as fibromyalgia often demonstrate hypervigilance-undue alertness for unpleasant or threatening bodily sensations-as well as enhancement of these sensations. The generalized hypervigilance hypothesis (GHH) of Rollman and colleagues asserts that hypervigilance leads to this perceptual amplification. However, cause-and-effect relationships are difficult to establish in studies using a quasi-experimental design. In the present study, we sought to address this issue by attempting to induce hypervigilance experimentally, in one of two groups to which young, healthy adults had been randomly assigned. Those in the experimental group wrote about the flu and practiced counting their own blinks, breaths, and heartbeats; those in the control group wrote about a neutral topic and counted innocuous lights and sounds. Next, both groups rated the intensity and unpleasantness of pressure sensations (ranging from mild to painful) caused by a series of applications of a weighted rod to the forearm. The intensity/unpleasantness ratio of these ratings was significantly greater in the experimental group, suggesting that induced hypervigilance had caused perceptual amplification that generalized to pressure sensations, which had not been part of the experimental manipulation. Psychometric measures of anxiety and catastrophizing were equivalent in the two groups, indicating that the experimental manipulation operated via attentional rather than emotional changes. The results support the GHH.

Supporting middle school students' construction of evidence-based arguments: Impact of and student interactions with computer-based argumentation scaffolds

NASA Astrophysics Data System (ADS)

Belland, Brian Robert

Middle school students have difficulty creating evidence-based arguments (EBAs) during problem-based learning (PBL) units due to challenges (a) adequately representing the unit's central problem (Ge & Land, 2004; Liu & Bera, 2005), (b) determining and obtaining the most relevant evidence (Pedersen & Liu, 2002-2003), and (c) synthesizing gathered information to construct a sound argument (Cho & Jonassen, 2002). I designed and developed the Connection Log to support middle school students in this process. This study addressed (1) the Connection Log's impact on (a) argument evaluation ability, and (b) group argument quality and (2) how and why middle school science students used the Connection Log. Four sections of a 7th-grade science class participated. Student groups selected a stakeholder position related to the Human Genome Project (HGP) and needed to decide on and promote a plan to use $3 million to further their position as pertains to the HGP. I randomly assigned one higher-achieving and one lower-achieving class to Connection Log or no Connection Log conditions. Students completed an argument evaluation test, and impact on argument evaluation ability was determined using nested ANOVA. Two graduate students, blind to treatment conditions, rated group arguments, and impact on group argument quality was determined using nested MANOVA. To determine how and why students used the Connection Log, I videotaped and interviewed one small group from each class in the experimental condition. I coded transcripts and generated themes, triangulating the two data sources with informal observations during all class sessions and what students wrote in the Connection Log. I detected no significant differences on claim, evidence, or connection of claim to evidence ratings of debate performances. However, students used the Connection Log to counter different difficulties, and I found a significant main effect of the Connection Log on argument evaluation ability, as well as a significant simple main effect of the Connection Log on argument evaluation ability of lower-achieving students. Implications include the Connection Log's potential to facilitate the creation of evidence-based arguments and the importance of (a) supporting English as a New Language students' efforts and (b) redundancy in communication.

20 CFR 404.750 - Evidence of a parent's support.

Code of Federal Regulations, 2011 CFR

2011-04-01

... DISABILITY INSURANCE (1950- ) Evidence Evidence for Child's and Parent's Benefits § 404.750 Evidence of a parent's support. If you apply for parent's benefits, we will ask you for evidence to show that you... 20 Employees' Benefits 2 2011-04-01 2011-04-01 false Evidence of a parent's support. 404.750...

20 CFR 404.750 - Evidence of a parent's support.

Code of Federal Regulations, 2013 CFR

2013-04-01

... DISABILITY INSURANCE (1950- ) Evidence Evidence for Child's and Parent's Benefits § 404.750 Evidence of a parent's support. If you apply for parent's benefits, we will ask you for evidence to show that you... 20 Employees' Benefits 2 2013-04-01 2013-04-01 false Evidence of a parent's support. 404.750...

20 CFR 404.750 - Evidence of a parent's support.

Code of Federal Regulations, 2014 CFR

2014-04-01

... DISABILITY INSURANCE (1950- ) Evidence Evidence for Child's and Parent's Benefits § 404.750 Evidence of a parent's support. If you apply for parent's benefits, we will ask you for evidence to show that you... 20 Employees' Benefits 2 2014-04-01 2014-04-01 false Evidence of a parent's support. 404.750...

20 CFR 404.750 - Evidence of a parent's support.

Code of Federal Regulations, 2012 CFR

2012-04-01

... DISABILITY INSURANCE (1950- ) Evidence Evidence for Child's and Parent's Benefits § 404.750 Evidence of a parent's support. If you apply for parent's benefits, we will ask you for evidence to show that you... 20 Employees' Benefits 2 2012-04-01 2012-04-01 false Evidence of a parent's support. 404.750...

Early Programming of Uterine Tissue by Bisphenol A: Critical Evaluation of Evidence from Animal Exposure Studies

PubMed Central

Suvorov, Alexander; Waxman, David J.

2015-01-01

Exposure to Bisphenol A (BPA) during the critical window of uterine development has been proposed to program the uterus for increased disease susceptibility based on well-documented effects of the potent xenoestrogen diethylstilbestrol. To investigate this proposal, we reviewed 37 studies of prenatal and/or perinatal BPA exposure in animal models and evaluated evidence for: molecular signatures of early BPA exposure; the development of adverse uterine health effects; and epigenetic changes linked to long-term dysregulation of uterine gene expression and health effects. We found substantial evidence for adult uterine effects of early BPA exposure. In contrast, experimental support for epigenetic actions of early BPA exposure is very limited, and largely consists of effects on Hoxa gene DNA methylation. Critical knowledge gaps were identified, including the need to fully characterize short-term and long-term uterine gene responses, interactions with estrogens and other endogenous hormones, and any long-lasting epigenetic signatures that impact adult disease. PMID:26028543

The Effectiveness of Adapted Versions of an Evidence-based Prevention Program in Reducing Alcohol Use among Alternative School Students

PubMed Central

Hopson, Laura M.; Holleran Steiker, Lori K.

2010-01-01

Although there is a strong evidence base for effective substance abuse prevention programs for youth, there is a need to facilitate the implementation and evaluation of these programs in real world settings. This study evaluates the effectiveness of adapted versions of an evidence-based prevention program, keepin’ it REAL (kiR), with alternative school students. Programs are often adapted when used in schools and other community settings for a variety of reasons. The kiR adaptations, developed during an earlier phase of this study, were created to make the curriculum more appropriate for alternative high school youth. The adaptations were evaluated using a quasi-experimental design in which questionnaires were administered at pretest, posttest, and follow-up, and focus groups were conducted at posttest. MANOVA analyses indicate significantly reduced intentions to accept alcohol and, for younger participants, reduced alcohol use. Focus group data support the need for age appropriate prevention content. The authors discuss implications for practitioners implementing prevention programs in schools. PMID:20622971

Mast cells in rheumatoid arthritis: friends or foes?

PubMed

Rivellese, Felice; Nerviani, Alessandra; Rossi, Francesca Wanda; Marone, Gianni; Matucci-Cerinic, Marco; de Paulis, Amato; Pitzalis, Costantino

2017-06-01

Mast cells are tissue-resident cells of the innate immunity, implicated in the pathogenesis of many autoimmune diseases, including rheumatoid arthritis (RA). They are present in synovia and their activation has been linked to the potentiation of inflammation in the course of RA. However, recent investigations questioned the role of mast cells in arthritis. In particular, animal models generated conflicting results, so that many of their pro-inflammatory, i.e. pro-arthritogenic functions, even though supported by robust experimental evidence, have been labelled as redundant. At the same time, a growing body of evidence suggests that mast cells can act as tunable immunomodulatory cells. These characteristics, not yet fully understood in the context of RA, could partially explain the inconsistent results obtained with experimental models, which do not account for the pro- and anti-inflammatory functions exerted in more chronic heterogeneous conditions such as RA. Here we present an overview of the current knowledge on mast cell involvement in RA, including the intriguing hypothesis of mast cells acting as subtle immunomodulatory cells and the emerging concept of synovial mast cells as potential biomarkers for patient stratification. Copyright © 2017 Elsevier B.V. All rights reserved.

Secondary metabolites in plant innate immunity: conserved function of divergent chemicals.

PubMed

Piasecka, Anna; Jedrzejczak-Rey, Nicolas; Bednarek, Paweł

2015-05-01

Plant secondary metabolites carry out numerous functions in interactions between plants and a broad range of other organisms. Experimental evidence strongly supports the indispensable contribution of many constitutive and pathogen-inducible phytochemicals to plant innate immunity. Extensive studies on model plant species, particularly Arabidopsis thaliana, have brought significant advances in our understanding of the molecular mechanisms underpinning pathogen-triggered biosynthesis and activation of defensive secondary metabolites. However, despite the proven significance of secondary metabolites in plant response to pathogenic microorganisms, little is known about the precise mechanisms underlying their contribution to plant immunity. This insufficiency concerns information on the dynamics of cellular and subcellular localization of defensive phytochemicals during the encounters with microbial pathogens and precise knowledge on their mode of action. As many secondary metabolites are characterized by their in vitro antimicrobial activity, these compounds were commonly considered to function in plant defense as in planta antibiotics. Strikingly, recent experimental evidence suggests that at least some of these compounds alternatively may be involved in controlling several immune responses that are evolutionarily conserved in the plant kingdom, including callose deposition and programmed cell death. © 2015 The Authors. New Phytologist © 2015 New Phytologist Trust.

The effect of acute microgravity on mechanically-induced membrane damage and membrane-membrane fusion events

NASA Technical Reports Server (NTRS)

Clarke, M. S.; Vanderburg, C. R.; Feeback, D. L.; McIntire, L. V. (Principal Investigator)

2001-01-01

Although it is unclear how a living cell senses gravitational forces there is no doubt that perturbation of the gravitational environment results in profound alterations in cellular function. In the present study, we have focused our attention on how acute microgravity exposure during parabolic flight affects the skeletal muscle cell plasma membrane (i.e. sarcolemma), with specific reference to a mechanically-reactive signaling mechanism known as mechanically-induced membrane disruption or "wounding". Both membrane rupture and membrane resealing events mediated by membrane-membrane fusion characterize this response. We here present experimental evidence that acute microgravity exposure can inhibit membrane-membrane fusion events essential for the resealing of sarcolemmal wounds in individual human myoblasts. Additional evidence to support this contention comes from experimental studies that demonstrate acute microgravity exposure also inhibits secretagogue-stimulated intracellular vesicle fusion with the plasma membrane in HL-60 cells. Based on our own observations and those of other investigators in a variety of ground-based models of membrane wounding and membrane-membrane fusion, we suggest that the disruption in the membrane resealing process observed during acute microgravity is consistent with a microgravity-induced decrease in membrane order.

Withania somnifera: from prevention to treatment of cancer

PubMed Central

Palliyaguru, Dushani L.; Singh, Shivendra V.; Kensler, Thomas W.

2016-01-01

The identification of bioactive molecules that have potential to interrupt carcinogenesis continues to garner research interest. In particular, molecules that have dietary origin are most attractive because of their safety, cost-effectiveness and feasibility of oral administration. Nutraceuticals have played an important role in the overall well-being of humans for many years, with or without rigorous evidence backing their health claims. Traditional medicine systems around the world have utilized plants for millennia that have medicinal properties, providing an opportunity for modern day researchers to assess their efficacies against ailments such as cancer. Withania somnifera (WS) is a plant that has been used in Ayurveda (an ancient form of medicine in Asia) and in the recent past, has been demonstrated to have anti-tumorigenic properties in experimental models. While scientific research performed on WS has exploded in the past decade, much regarding the mode of action and molecular targets involved remains unknown. In this review, we discuss the traditional uses of the plant, the experimental evidence supporting its chemopreventive potential as well as roadblocks that need to be overcome in order for WS to be evaluated as a chemopreventive agent in humans. PMID:26718910

Genetic Complementation of the Obligate Marine Actinobacterium Salinispora tropica with the Large Mechanosensitive Channel Gene mscL Rescues Cells from Osmotic Downshock

PubMed Central

Bucarey, Sergio A.; Penn, Kevin; Paul, Lauren; Fenical, William

2012-01-01

Marine actinomycetes in the genus Salinispora fail to grow when seawater is replaced with deionized (DI) water in complex growth media. While bioinformatic analyses have led to the identification of a number of candidate marine adaptation genes, there is currently no experimental evidence to support the genetic basis for the osmotic requirements associated with this taxon. One hypothesis is that the lineage-specific loss of mscL is responsible for the failure of strains to grow in media prepared with DI water. The mscL gene encodes a conserved transmembrane protein that reduces turgor pressure under conditions of acute osmotic downshock. In the present study, the mscL gene from a Micromonospora strain capable of growth on media prepared with DI water was transformed into S. tropica strain CNB-440. The single-copy, chromosomal genetic complementation yielded a recombinant Salinispora mscL+ strain that demonstrated an increased capacity to survive osmotic downshock. The enhanced survival of the S. tropica transformant provides experimental evidence that the loss of mscL is associated with the failure of Salinispora spp. to grow in low-osmotic-strength media. PMID:22492446

[Disinfecting contact tonometers - a systematic review].

PubMed

Neubauer, A S; Heeg, P; Kampik, A; Hirneiss, C

2009-05-01

The aim of this study is to provide the best available evidence on how to disinfect contact Goldman tonometers. A systematic review of all articles on disinfection of contact tonometers was conducted. Articles published up to July 2008 were identified in Medline, Embase and references from included articles. Two observers participated in the data retrieval and assessment of the studies identified. A total of 89 articles was retrieved, of which 58 could be included. Of those, 18 were clinical studies, 17 experimental microbiological studies, 8 expert assessments or guidelines and 15 reviews, surveys, descriptions of new methods. The clinical studies illustrate the importance of the problem, possible side effects of some disinfection methods but yield inconclusive results regarding efficacy. Experimental studies investigated a variety of bacterial and virological questions as well as material damage by disinfection. Both chlorine-based and hydrogen peroxide-based liquid disinfection were shown to be effective if applied for 5 min. Inconsistent results exist for alcohol wipes and UV disinfection - material damage has been described for both. The US guidelines and most expert recommendations are supported by evidence of the existing data. Chlorine-based and hydrogen peroxide-based liquid disinfections for 5 minutes are effective and relatively safe for disinfecting contact tonometers.

Remifentanil-acute opioid tolerance and opioid-induced hyperalgesia: a systematic review.

PubMed

Kim, Sang Hun; Stoicea, Nicoleta; Soghomonyan, Suren; Bergese, Sergio D

2015-01-01

The use of opioids may seem to be a double-edged sword; they provide straight analgesic and antihyperalgesic effects initially, but subsequently are associated with the expression of acute opioid tolerance (AOT) and opioid-induced hyperalgesia (OIH) that have been reported in experimental studies and clinical observations. It has been suggested that opioids can induce an acute tolerance and hyperalgesia in dose- and/or time-dependent manners even when used within the clinically accepted doses. Recently, remifentanil has been used for pain management in clinical anesthesia and in the intensive care units because of its rapid onset and offset. We reviewed articles analyzing AOT and/or OIH by remifentanil and focused on the following issues: (1) evidence of remifentanil inducing AOT and/or OIH and (2) importance of AOT and/or OIH in considering the reduction of remifentanil dosage or adopting preventive modulations. Twenty-four experimental and clinical studies were identified using electronic searches of MEDLINE (PubMed, Ovid, Springer, and Elsevier). However, the development of AOT and OIH by remifentanil administration remains controversial. There is no sufficient evidence to support or refute the existence of OIH in humans.

Efficacy and safety of herbal stimulants and sedatives in sleep disorders.

PubMed

Gyllenhaal, Charlotte; Merritt, Sharon L.; Peterson, Sara Davia; Block, Keith I.; Gochenour, Tom

2000-06-01

World-wide use of herbal medicines is increasing, following regulatory and manufacturing developments. Herbs are attractive alternative medications to many patients with sleep disorders, who may be averse to using conventional drugs. We review here the most common herbal stimulants and sedatives. Caffeine, in herbal teas, black tea, coffee, soft drinks and pharmaceuticals, is used widely to control sleepiness, but more research is needed on its use in sleep disorders. Ephedra, and its constituent ephedrine, are used in both stimulant and weight loss preparations, sometimes with caffeine; safety concerns have arisen with this practice. Yohimbe is another herb used in stimulant and body-building preparations which has safety concerns. Asian and Siberian ginseng have been traditionally used for fatigue, and have some supportive experimental evidence for this use. Herbal sedatives also have some evidence for efficacy; the observations that certain plant flavonoid compounds bind to benzodiazepine receptors adds interest to their use. Valerian and kava have received the most research attention; both have decreased sleep onset time and promoted deeper sleep in small studies, and kava also shows anxiolytic effects. German chamomile, lavender, hops, lemon balm and passionflower are reputed to be mild sedatives but need much more experimental examination.

Programming by early nutrition: an experimental approach.

PubMed

Lucas, A

1998-02-01

That events during critical or sensitive periods of development may "program" long-term or life-time structure or function of the organism is well recognized. Evidence for programming by nutrition is established in animals, in whom brief pre- or postnatal nutritional manipulations may program adult size, metabolism, blood lipids, diabetes, blood pressure, obesity, atherosclerosis, learning, behavior and life span. Human epidemiological data link potential markers of early nutrition (size at birth or in infancy) to cardiovascular disease and its risk factors in adulthood. However, these retrospective data cannot prove nutritional cause or underpin health policies. After 16 y, however, of ethical, randomized intervention studies of early nutrition in humans with long-term follow-up to test experimentally the nutritional programming hypothesis, we find that humans, like other species, have sensitive windows for nutrition in terms of later outcomes; for instance, perinatal diet influences neurodevelopment and bone mineralization into mid-childhood. Possible biological mechanisms for storing throughout life the "memory" of early nutritional experience and its expression in adulthood include adaptive changes in gene expression, preferential clonal selection of adapted cells in programmed tissues and programmed differential proliferation of tissue cell types. Animal and human evidence supporting nutritional programming has major potential biological and medical significance.

The Effect of Acute Microgravity on Mechanically-Induced Membrane Damage and Membrane-Membrane Fusion Events

NASA Technical Reports Server (NTRS)

Clarke, Mark, S. F.; Vanderburg, Charles R.; Feedback, Daniel L.

2001-01-01

Although it is unclear how a living cell senses gravitational forces there is no doubt that perturbation of the gravitational environment results in profound alterations in cellular function. In the present study, we have focused our attention on how acute microgravity exposure during parabolic flight affects the skeletal muscle cell plasma membrane (i.e. sarcolemma), with specific reference to a mechanically-reactive signaling mechanism known as mechanically-induced membrane disruption or "wounding". This response is characterized by both membrane rupture and membrane resealing events mediated by membrane-membrane fusion. We here present experimental evidence that acute microgravity exposure can inhibit membrane-membrane fusion events essential for the resealing of sarcolemmal wounds in individual human myoblasts. Additional evidence to support this contention comes from experimental studies that demonstrate acute microgravity exposure also inhibits secretagogue-stimulated intracellular vesicle fusion with the plasma membrane in HL-60 cells. Based on our own observations and those of other investigators in a variety of ground-based models of membrane wounding and membrane-membrane fusion, we suggest that the disruption in the membrane resealing process observed during acute microgravity is consistent with a microgravity-induced decrease in membrane order.

Sweet sixteen for ANLS

PubMed Central

Pellerin, Luc; Magistretti, Pierre J

2012-01-01

Since its introduction 16 years ago, the astrocyte–neuron lactate shuttle (ANLS) model has profoundly modified our understanding of neuroenergetics by bringing a cellular and molecular resolution. Praised or disputed, the concept has never ceased to attract attention, leading to critical advances and unexpected insights. Here, we summarize recent experimental evidence further supporting the main tenets of the model. Thus, evidence for distinct metabolic phenotypes between neurons (mainly oxidative) and astrocytes (mainly glycolytic) have been provided by genomics and classical metabolic approaches. Moreover, it has become clear that astrocytes act as a syncytium to distribute energy substrates such as lactate to active neurones. Glycogen, the main energy reserve located in astrocytes, is used as a lactate source to sustain glutamatergic neurotransmission and synaptic plasticity. Lactate is also emerging as a neuroprotective agent as well as a key signal to regulate blood flow. Characterization of monocarboxylate transporter regulation indicates a possible involvement in synaptic plasticity and memory. Finally, several modeling studies captured the implications of such findings for many brain functions. The ANLS model now represents a useful, experimentally based framework to better understand the coupling between neuronal activity and energetics as it relates to neuronal plasticity, neurodegeneration, and functional brain imaging. PMID:22027938

Knowledge engineering tools for reasoning with scientific observations and interpretations: a neural connectivity use case.

PubMed

Russ, Thomas A; Ramakrishnan, Cartic; Hovy, Eduard H; Bota, Mihail; Burns, Gully A P C

2011-08-22

We address the goal of curating observations from published experiments in a generalizable form; reasoning over these observations to generate interpretations and then querying this interpreted knowledge to supply the supporting evidence. We present web-application software as part of the 'BioScholar' project (R01-GM083871) that fully instantiates this process for a well-defined domain: using tract-tracing experiments to study the neural connectivity of the rat brain. The main contribution of this work is to provide the first instantiation of a knowledge representation for experimental observations called 'Knowledge Engineering from Experimental Design' (KEfED) based on experimental variables and their interdependencies. The software has three parts: (a) the KEfED model editor - a design editor for creating KEfED models by drawing a flow diagram of an experimental protocol; (b) the KEfED data interface - a spreadsheet-like tool that permits users to enter experimental data pertaining to a specific model; (c) a 'neural connection matrix' interface that presents neural connectivity as a table of ordinal connection strengths representing the interpretations of tract-tracing data. This tool also allows the user to view experimental evidence pertaining to a specific connection. BioScholar is built in Flex 3.5. It uses Persevere (a noSQL database) as a flexible data store and PowerLoom® (a mature First Order Logic reasoning system) to execute queries using spatial reasoning over the BAMS neuroanatomical ontology. We first introduce the KEfED approach as a general approach and describe its possible role as a way of introducing structured reasoning into models of argumentation within new models of scientific publication. We then describe the design and implementation of our example application: the BioScholar software. This is presented as a possible biocuration interface and supplementary reasoning toolkit for a larger, more specialized bioinformatics system: the Brain Architecture Management System (BAMS).

Knowledge engineering tools for reasoning with scientific observations and interpretations: a neural connectivity use case

PubMed Central

2011-01-01

Background We address the goal of curating observations from published experiments in a generalizable form; reasoning over these observations to generate interpretations and then querying this interpreted knowledge to supply the supporting evidence. We present web-application software as part of the 'BioScholar' project (R01-GM083871) that fully instantiates this process for a well-defined domain: using tract-tracing experiments to study the neural connectivity of the rat brain. Results The main contribution of this work is to provide the first instantiation of a knowledge representation for experimental observations called 'Knowledge Engineering from Experimental Design' (KEfED) based on experimental variables and their interdependencies. The software has three parts: (a) the KEfED model editor - a design editor for creating KEfED models by drawing a flow diagram of an experimental protocol; (b) the KEfED data interface - a spreadsheet-like tool that permits users to enter experimental data pertaining to a specific model; (c) a 'neural connection matrix' interface that presents neural connectivity as a table of ordinal connection strengths representing the interpretations of tract-tracing data. This tool also allows the user to view experimental evidence pertaining to a specific connection. BioScholar is built in Flex 3.5. It uses Persevere (a noSQL database) as a flexible data store and PowerLoom® (a mature First Order Logic reasoning system) to execute queries using spatial reasoning over the BAMS neuroanatomical ontology. Conclusions We first introduce the KEfED approach as a general approach and describe its possible role as a way of introducing structured reasoning into models of argumentation within new models of scientific publication. We then describe the design and implementation of our example application: the BioScholar software. This is presented as a possible biocuration interface and supplementary reasoning toolkit for a larger, more specialized bioinformatics system: the Brain Architecture Management System (BAMS). PMID:21859449

Pharmacology of Myopia and Potential Role for Intrinsic Retinal Circadian Rhythms

PubMed Central

Stone, Richard A.; Pardue, Machelle T.; Iuvone, P. Michael; Khurana, Tejvir S.

2013-01-01

Despite the high prevalence and public health impact of refractive errors, the mechanisms responsible for ametropias are poorly understood. Much evidence now supports the concept that the retina is central to the mechanism(s) regulating emmetropization and underlying refractive errors. Using a variety of pharmacologic methods and well-defined experimental eye growth models in laboratory animals, many retinal neurotransmitters and neuromodulators have been implicated in this process. Nonetheless, an accepted framework for understanding the molecular and/or cellular pathways that govern postnatal eye development is lacking. Here, we review two extensively studied signaling pathways whose general roles in refractive development are supported by both experimental and clinical data: acetylcholine signaling through muscarinic and/or nicotinic acetylcholine receptors and retinal dopamine pharmacology. The muscarinic acetylcholine receptor antagonist atropine was first studied as an anti-myopia drug some two centuries ago, and much subsequent work has continued to connect muscarinic receptors to eye growth regulation. Recent research implicates a potential role of nicotinic acetycholine receptors; and the refractive effects in population surveys of passive exposure to cigarette smoke, of which nicotine is a constituent, support clinical relevance. Reviewed here, many puzzling results inhibit formulating a mechanistic framework that explains acetylcholine’s role in refractive development. How cholinergic receptor mechanisms might be used to develop acceptable approaches to normalize refractive development remains a challenge. Retinal dopamine signaling not only has a putative role in refractive development, its upregulation by light comprises an important component of the retinal clock network and contributes to the regulation of retinal circadian physiology. During postnatal development, the ocular dimensions undergo circadian and/or diurnal fluctuations in magnitude; these rhythms shift in eyes developing experimental ametropia. Long-standing clinical ideas about myopia in particular have postulated a role for ambient lighting, although molecular or cellular mechanisms for these speculations have remained obscure. Experimental myopia induced by the wearing of a concave spectacle lens alters the retinal expression of a significant proportion of intrinsic circadian clock genes, as well as genes encoding a melatonin receptor and the photopigment melanopsin. Together this evidence suggests a hypothesis that the retinal clock and intrinsic retinal circadian rhythms may be fundamental to the mechanism(s) regulating refractive development, and that disruptions in circadian signals may produce refractive errors. Here we review the potential role of biological rhythms in refractive development. While much future research is needed, this hypothesis could unify many of the disparate clinical and laboratory observations addressing the pathogenesis of refractive errors. PMID:23313151

Review: fetal programming of polycystic ovary syndrome by androgen excess: evidence from experimental, clinical, and genetic association studies.

PubMed

Xita, Nectaria; Tsatsoulis, Agathocles

2006-05-01

Polycystic ovary syndrome (PCOS) is a common endocrine disorder of premenopausal women, characterized by hyperandrogenism, polycystic ovaries, and chronic anovulation along with insulin resistance and abdominal obesity as frequent metabolic traits. Although PCOS manifests clinically during adolescence, emerging data suggest that the natural history of PCOS may originate in intrauterine life. Evidence from experimental, clinical, and genetic research supporting the hypothesis for the fetal origins of PCOS has been analyzed. Female primates, exposed in utero to androgen excess, exhibit the phenotypic features of PCOS during adult life. Clinical observations also support a potential fetal origin of PCOS. Women with fetal androgen excess disorders, including congenital 21-hydroxylase deficiency and congenital adrenal virilizing tumors, develop features characteristic of PCOS during adulthood despite the normalization of androgen excess after birth. The potential mechanisms of fetal androgen excess leading to a PCOS phenotype in humans are not clearly understood. However, maternal and/or fetal hyperandrogenism can provide a plausible mechanism for fetal programing of PCOS, and this, in part, may be genetically determined. Thus, genetic association studies have indicated that common polymorphic variants of genes determining androgen activity or genes that influence the availability of androgens to target tissues are associated with PCOS and increased androgen levels. These genomic variants may provide the genetic link to prenatal androgenization in human PCOS. Prenatal androgenization of the female fetus induced by genetic and environmental factors, or the interaction of both, may program differentiating target tissues toward the development of PCOS phenotype in adult life.

Mechanisms of eyewitness suggestibility: tests of the explanatory role hypothesis.

PubMed

Rindal, Eric J; Chrobak, Quin M; Zaragoza, Maria S; Weihing, Caitlin A

2017-10-01

In a recent paper, Chrobak and Zaragoza (Journal of Experimental Psychology: General, 142(3), 827-844, 2013) proposed the explanatory role hypothesis, which posits that the likelihood of developing false memories for post-event suggestions is a function of the explanatory function the suggestion serves. In support of this hypothesis, they provided evidence that participant-witnesses were especially likely to develop false memories for their forced fabrications when their fabrications helped to explain outcomes they had witnessed. In three experiments, we test the generality of the explanatory role hypothesis as a mechanism of eyewitness suggestibility by assessing whether this hypothesis can predict suggestibility errors in (a) situations where the post-event suggestions are provided by the experimenter (as opposed to fabricated by the participant), and (b) across a variety of memory measures and measures of recollective experience. In support of the explanatory role hypothesis, participants were more likely to subsequently freely report (E1) and recollect the suggestions as part of the witnessed event (E2, source test) when the post-event suggestion helped to provide a causal explanation for a witnessed outcome than when it did not serve this explanatory role. Participants were also less likely to recollect the suggestions as part of the witnessed event (on measures of subjective experience) when their explanatory strength had been reduced by the presence of an alternative explanation that could explain the same outcome (E3, source test + warning). Collectively, the results provide strong evidence that the search for explanatory coherence influences people's tendency to misremember witnessing events that were only suggested to them.

Interaction of language, auditory and memory brain networks in auditory verbal hallucinations.

PubMed

Ćurčić-Blake, Branislava; Ford, Judith M; Hubl, Daniela; Orlov, Natasza D; Sommer, Iris E; Waters, Flavie; Allen, Paul; Jardri, Renaud; Woodruff, Peter W; David, Olivier; Mulert, Christoph; Woodward, Todd S; Aleman, André

2017-01-01

Auditory verbal hallucinations (AVH) occur in psychotic disorders, but also as a symptom of other conditions and even in healthy people. Several current theories on the origin of AVH converge, with neuroimaging studies suggesting that the language, auditory and memory/limbic networks are of particular relevance. However, reconciliation of these theories with experimental evidence is missing. We review 50 studies investigating functional (EEG and fMRI) and anatomic (diffusion tensor imaging) connectivity in these networks, and explore the evidence supporting abnormal connectivity in these networks associated with AVH. We distinguish between functional connectivity during an actual hallucination experience (symptom capture) and functional connectivity during either the resting state or a task comparing individuals who hallucinate with those who do not (symptom association studies). Symptom capture studies clearly reveal a pattern of increased coupling among the auditory, language and striatal regions. Anatomical and symptom association functional studies suggest that the interhemispheric connectivity between posterior auditory regions may depend on the phase of illness, with increases in non-psychotic individuals and first episode patients and decreases in chronic patients. Leading hypotheses involving concepts as unstable memories, source monitoring, top-down attention, and hybrid models of hallucinations are supported in part by the published connectivity data, although several caveats and inconsistencies remain. Specifically, possible changes in fronto-temporal connectivity are still under debate. Precise hypotheses concerning the directionality of connections deduced from current theoretical approaches should be tested using experimental approaches that allow for discrimination of competing hypotheses. Copyright © 2016 The Authors. Published by Elsevier Ltd.. All rights reserved.

Experimental High Energy Physics Research: Direct Detection of Dark Matter

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

Witherell, Michael S.

2014-10-02

The grant supported research on an experimental search for evidence of dark matter interactions with normal matter. The PI carried out the research as a member of the LUX and LZ collaborations. The LUX research team collected a first data set with the LUX experiment, a large liquid xenon detector installed in the Sanford Underground Research Facility (SURF). The first results were published in Physical Review Letters on March 4, 2014. The journal Nature named the LUX result a scientific highlight of the year for 2013. In addition, the LZ collaboration submitted the full proposal for the Lux Zeplin experiment,more » which has since been approved by DOE-HEP as a second-generation dark matter experiment. Witherell is the Level 2 manager for the Outer Detector System on the LUX-Zeplin experiment.« less

Alternative Interpretation of Low-Energy Nuclear Reaction Processes with Deuterated Metals Based on the Bose-Einstein Condensation Mechanism

NASA Astrophysics Data System (ADS)

Kim, Yeong E.; Passell, Thomas O.

2006-02-01

Recently, a generalization of the Bose-Einstein condensation (BEC) mechanism has been made to a ground-state mixture of two different species of positively charged bosons in harmonic traps. The theory has been used to describe (D + Li) reactions in the low energy nuclear reaction (LENR) processes in condensed matter and predicts that the (D + Li) reaction rates can be larger than (D + D) reaction rates by as much as a factor of ~50, implying that (D + Li) reactions may be occuring in addition to the (D + D) reactions. A survey of the existing data from LENR experiments is carried out to check the validity of the theoretical prediction. We conclude that there is compelling experimental evidence which support the theoretical prediction. New experimental tests of the theoretical prediction are suggested.

A gastrointestinal anti-infectious biotherapeutic agent: the heat-treated Lactobacillus LB

PubMed Central

Liévin-Le Moal, Vanessa

2016-01-01

Experimental in vitro and in vivo studies support the hypothesis that heat-treated, lyophilized Lactobacillus acidophilus LB cells and concentrated, neutralized spent culture medium conserve the variety of pharmacological, antimicrobial activities of the live probiotic strain against several infectious agents involved in well-established acute and persistent watery diarrhoea and gastritis. Heat-treated cells and heat-stable secreted molecules trigger multiple strain-specific activities explaining the therapeutic efficacy of L. acidophilus LB. This review discusses the current body of knowledge on the antimicrobial mechanisms of action exerted by L. acidophilus LB demonstrated in in vitro and in vivo experimental studies, and the evidence for the therapeutic efficacy of this anti-infectious biotherapeutic agent proved in randomized clinical trials for the treatment of acute and persistent watery diarrhoea associated with several intestinal infectious diseases in humans. PMID:26770268

Does community social embeddedness promote generalized trust? An experimental test of the spillover effect.

PubMed

Lo Iacono, Sergio

2018-07-01

Despite the theoretical relevance attributed to the spillover effect, little empirical research has focused on testing its causal validity. Addressing this gap in the literature, I propose a novel experimental design to test if the overall density of social links in a community promotes trustworthy and trusting behaviors with absolute strangers. Controlling for social integration (i.e. the individual number of social connections), I found that density fosters higher levels of trust. In particular, results show that people in denser communities are more likely to trust their unknown fellow citizens, encouraging isolated subjects to engage with strangers. However, evidence did not support the idea that community social embeddedness causes an increase of trustworthiness, indicating that the spillover effect works only with respect to trust. Copyright © 2018 Elsevier Inc. All rights reserved.

Experimental evidence of Cr magnetic moments at low temperature in Cr2A(A=Al, Ge)C.

PubMed

Jaouen, M; Bugnet, M; Jaouen, N; Ohresser, P; Mauchamp, V; Cabioc'h, T; Rogalev, A

2014-04-30

From x-ray magnetic circular dichroism experiments performed at low temperature on Cr2AlC and Cr2GeC thin films, it is evidenced that Cr atoms carry a net magnetic moment in these ternary phases. It is shown that the Cr magnetization of the Al-based compound nearly vanished at 100 K in agreement with what has been recently observed on bulk. X-ray linear dichroism measurements performed at various angles of incidence and temperatures clearly demonstrate the existence of a charge ordering along the c axis of the structure of Cr2AlC. All these experimental observations support, in part, theoretical calculations claiming that Cr dd correlations have to be considered to correctly describe the structure and properties of these Cr-based ternary phases.

A note on the coupling between flow instabilities and incident sound

NASA Astrophysics Data System (ADS)

Ahuja, K. K.; Tam, C. K. W.

1982-08-01

It is noted that the mechanisms by which instability waves are produced have received little attention because of the formidable theoretical and experimental difficulties. Little progress is expected in predicting flow behavior, for example, laminar-to-turbulent flow transition, until some way is found to deal with instability waves in terms of the disturbances that cause them. Before a detailed investigation is carried out to investigate receptivity, it is important to resolve the differences found in the literature on the theoretical notions about the receptivity itself. The objective here is to address these differences and to present some preliminary experimental results that are considered extremely relevant. Using a laser schlieren system and a process of photographic averaging, qualitative evidence is obtained that supports the contention that instability waves can be excited without the coupling of a solid trailing edge.

Noise-figure limit of fiber-optical parametric amplifiers and wavelength converters: experimental investigation

NASA Astrophysics Data System (ADS)

Tang, Renyong; Voss, Paul L.; Lasri, Jacob; Devgan, Preetpaul; Kumar, Prem

2004-10-01

Recent theoretical work predicts that the quantum-limited noise figure of a chi(3)-based fiber-optical parametric amplifier operating as a phase-insensitive in-line amplifier or as a wavelength converter exceeds the standard 3-dB limit at high gain. The degradation of the noise figure is caused by the excess noise added by the unavoidable Raman gain and loss occurring at the signal and the converted wavelengths. We present detailed experimental evidence in support of this theory through measurements of the gain and noise-figure spectra for phase-insensitive parametric amplification and wavelength conversion in a continuous-wave amplifier made from 4.4 km of dispersion-shifted fiber. The theory is also extended to include the effect of distributed linear loss on the noise figure of such a long-length parametric amplifier and wavelength converter.

The change in aggressiveness of neoplasms with age.

PubMed

Ershler, W B

1987-01-01

With aging, tumors occur more frequently. The "malignant" characteristics of tumors (ie, rapid growth and metastases), however, appear to be less prominent in the elderly. In experimental tumor models, similar observations have been recorded. The reason for this phenomenon could be that tumors (ie, malignant cells) are different in different-aged hosts. Alternatively, host features such as the fibrotic, angiogenic, or immune response may be altered by the aging process and may render the host "soil" less fertile for "malignant" tumor growth. Indeed, experimental evidence has supported the importance of each of these host features. The significance of the exploration and eventual understanding of the age-related change in tumor behavior extends beyond clinical geriatric medicine; it may, in fact, involve the very unraveling of some of the basic biology of both tumor control and the aging process itself.

Stability analysis applied to the early stages of viscous drop breakup by a high-speed gas stream

NASA Astrophysics Data System (ADS)

Padrino, Juan C.; Longmire, Ellen K.

2013-11-01

The instability of a liquid drop suddenly exposed to a high-speed gas stream behind a shock wave is studied by considering the gas-liquid motion at the drop interface. The discontinuous velocity profile given by the uniform, parallel flow of an inviscid, compressible gas over a viscous liquid is considered, and drop acceleration is included. Our analysis considers compressibility effects not only in the base flow, but also in the equations of motion for the perturbations. Recently published high-resolution images of the process of drop breakup by a passing shock have provided experimental evidence supporting the idea that a critical gas dynamic pressure can be found above which drop piercing by the growth of acceleration-driven instabilities gives way to drop breakup by liquid entrainment resulting from the gas shearing action. For a set of experimental runs from the literature, results show that, for shock Mach numbers >= 2, a band of rapidly growing waves forms in the region well upstream of the drop's equator at the location where the base flow passes from subsonic to supersonic, in agreement with experimental images. Also, the maximum growth rate can be used to predict the transition of the breakup mode from Rayleigh-Taylor piercing to shear-induced entrainment. The authors acknowledge support of the NSF (DMS-0908561).

Improving Health Promotion Using Quality Improvement Techniques in Australian Indigenous Primary Health Care

PubMed Central

Percival, Nikki; O’Donoghue, Lynette; Lin, Vivian; Tsey, Komla; Bailie, Ross Stewart

2016-01-01

Although some areas of clinical health care are becoming adept at implementing continuous quality improvement (CQI) projects, there has been limited experimentation of CQI in health promotion. In this study, we examined the impact of a CQI intervention on health promotion in four Australian Indigenous primary health care centers. Our study objectives were to (a) describe the scope and quality of health promotion activities, (b) describe the status of health center system support for health promotion activities, and (c) introduce a CQI intervention and examine the impact on health promotion activities and health centers systems over 2 years. Baseline assessments showed suboptimal health center systems support for health promotion and significant evidence-practice gaps. After two annual CQI cycles, there were improvements in staff understanding of health promotion and systems for planning and documenting health promotion activities had been introduced. Actions to improve best practice health promotion, such as community engagement and intersectoral partnerships, were inhibited by the way health center systems were organized, predominately to support clinical and curative services. These findings suggest that CQI can improve the delivery of evidence-based health promotion by engaging front line health practitioners in decision-making processes about the design/redesign of health center systems to support the delivery of best practice health promotion. However, further and sustained improvements in health promotion will require broader engagement of management, senior staff, and members of the local community to address organizational and policy level barriers. PMID:27066470

Improving Health Promotion Using Quality Improvement Techniques in Australian Indigenous Primary Health Care.

PubMed

Percival, Nikki; O'Donoghue, Lynette; Lin, Vivian; Tsey, Komla; Bailie, Ross Stewart

2016-01-01

Although some areas of clinical health care are becoming adept at implementing continuous quality improvement (CQI) projects, there has been limited experimentation of CQI in health promotion. In this study, we examined the impact of a CQI intervention on health promotion in four Australian Indigenous primary health care centers. Our study objectives were to (a) describe the scope and quality of health promotion activities, (b) describe the status of health center system support for health promotion activities, and (c) introduce a CQI intervention and examine the impact on health promotion activities and health centers systems over 2 years. Baseline assessments showed suboptimal health center systems support for health promotion and significant evidence-practice gaps. After two annual CQI cycles, there were improvements in staff understanding of health promotion and systems for planning and documenting health promotion activities had been introduced. Actions to improve best practice health promotion, such as community engagement and intersectoral partnerships, were inhibited by the way health center systems were organized, predominately to support clinical and curative services. These findings suggest that CQI can improve the delivery of evidence-based health promotion by engaging front line health practitioners in decision-making processes about the design/redesign of health center systems to support the delivery of best practice health promotion. However, further and sustained improvements in health promotion will require broader engagement of management, senior staff, and members of the local community to address organizational and policy level barriers.

Use of evidence in the process of practice change in a clinical team: a study-forming part of the Autocontrol Project.

PubMed

Mehta, V; Kushniruk, A; Gauthier, S; Richard, Y; Deland, E; Veilleux, M; Grant, A

1998-01-01

The Autocontrol Project is concerned with the accessing, processing and communication of high quality information so that a clinical team can make and implement decisions for practice change, and then evaluate if improvement has been achieved. High quality information is used as evidence for change. In this study, we have evaluated how evidence is used by a clinical team to explain an identified problem of inappropriate use of blood gas tests. In an experimental study of the Surgical Intensive Care Unit, video recordings of team meetings of nurses and doctors were undertaken, structured according to a problem-based format. Evidence of current practice patterns derived from the hospital information system, as well as the results of a questionnaire to the unit's staff about knowledge and use of blood gas measurements, were supplied to the participants beforehand. At the second meeting, the output of the first meetings and a summarised analysis of pertinent literature were made available. This second meeting was required to finalise the list of causes of inappropriate blood gas use and propose pragmatic strategies for practice change. The video data of the meetings were coded to analyse the use of evidence, the categories of causes, issues and solutions proposed, and the quality of team interaction. The results indicate that in order to achieve consensus, the team used different types of evidence, including objective evidence of practice patterns, personal experience about direct and indirect organisational influences, and literature-based research evidence of best practice. Furthermore, group dynamics were favoured by the problem-based meeting structure, and a high level of cognitive critiquing between team members was observed. This research suggests that a combination of approaches involving identification of both operational factors (e.g. appropriate access to different types of evidence and meeting structure) and cognitive and behavioural approaches (e.g. ensuring expression of different viewpoints) is needed to support strategic decision-making for practice change in a clinical unit. This combined approach should favourably influence the provision of an effective and efficient evidence support environment for the clinical team.

The effects of autonomy support on salivary alpha-amylase: The role of individual differences.

PubMed

Sieber, Vanda; Schüler, Julia; Wegner, Mirko

2016-12-01

The empirical evidence for the relationship between autonomy-supportive environments and physiological stress is inconsistent. Whereas some studies report a decrease in stress in autonomy-supportive environments, other studies show a negative effect of autonomy on physiological stress. As previous research has not considered individual differences within this relationship, the present research aims to close this empirical gap by proposing that an implicit autonomy disposition, which is defined as a dispositional preference for self-determination, serves as a moderator. In an experiment, we tested whether the autonomy disposition moderates the effect of different teaching styles (controlling, autonomy-supportive, and neutral) on the acute physiological stress response (salivary alpha-amylase) in adolescents (N=69). The study revealed that participants with a high implicit autonomy disposition displayed lower salivary alpha-amylase responses when exposed to autonomy-supportive vignettes compared to when they were exposed to controlling or neutral teaching styles. The opposite pattern was found in students with a low implicit autonomy disposition. The results illustrate that experimentally induced variations in autonomy support lead to different physiological stress responses, depending on individual differences in the implicit autonomy disposition. Copyright © 2016 Elsevier Ltd. All rights reserved.

NETopathies? Unraveling the Dark Side of Old Diseases through Neutrophils.

PubMed

Mitsios, Alexandros; Arampatzioglou, Athanasios; Arelaki, Stella; Mitroulis, Ioannis; Ritis, Konstantinos

2016-01-01

Neutrophil extracellular traps (NETs) were initially described as an antimicrobial mechanism of neutrophils. Over the last decade, several lines of evidence support the involvement of NETs in a plethora of pathological conditions. Clinical and experimental data indicate that NET release constitutes a shared mechanism, which is involved in a different degree in various manifestations of non-infectious diseases. Even though the backbone of NETs is similar, there are differences in their protein load in different diseases, which represent alterations in neutrophil protein expression in distinct disorder-specific microenvironments. The characterization of NET protein load in different NET-driven disorders could be of significant diagnostic and/or therapeutic value. Additionally, it will provide further evidence for the role of NETs in disease pathogenesis, and it will enable the characterization of disorders in which neutrophils and NET-dependent inflammation are of critical importance.

Drug Interactions with Lithium: An Update.

PubMed

Finley, Patrick R

2016-08-01

Lithium has been used for the management of psychiatric illnesses for over 50 years and it continues to be regarded as a first-line agent for the treatment and prevention of bipolar disorder. Lithium possesses a narrow therapeutic index and comparatively minor alterations in plasma concentrations can have significant clinical sequelae. Several drug classes have been implicated in the development of lithium toxicity over the years, including diuretics and non-steroidal anti-inflammatory compounds, but much of the anecdotal and experimental evidence supporting these interactions is dated, and many newer medications and medication classes have been introduced during the intervening years. This review is intended to provide an update on the accumulated evidence documenting potential interactions with lithium, with a focus on pharmacokinetic insights gained within the last two decades. The clinical relevance and ramifications of these interactions are discussed.

Does artificial nutrition improve outcome of critical illness? An alternative viewpoint!

PubMed

Heyland, Daren K; Wischmeyer, Paul E

2013-08-27

Recent studies challenge the beneficial role of artificial nutrition provided to critically ill patients and point out the limitations of existing studies in this area. We take a differing view of the existing data and refute many of the arguments put forward by previous authors. We review the mechanistic, observational, and experimental data supporting a role for early enteral nutrition in the critically ill patient. We conclude without question that more, high-quality research is needed to better define the role of artificial nutrition in the critical care setting, but until then early and adequate delivery of enteral nutrition is a legitimate, evidence-based treatment recommendation and we see no evidence-based role for restricting enteral nutrition in critically ill patients. The role of early supplemental parenteral nutrition continues to be defined as new data emerge.

Theory of mind training causes honest young children to lie

PubMed Central

Ding, Xiao Pan; Wellman, Henry; Wang, Yu; Fu, Genyue; Lee, Kang

2015-01-01

Theory of mind (ToM) has long been recognized to play a major role in children’s social functioning. However, no direct evidence confirms the causal linkage between the two. Here we addressed this significant gap by examining whether ToM causes the emergence of lying, an important social skill. We showed that after participating in ToM training to learn about mental state concepts, 3-year-olds who originally had been unable to lie began to deceive consistently. This training effect lasted for more than a month. In contrast, 3-year-olds who participated in control training to learn about physical concepts were significantly less inclined to lie than the ToM trained children. These findings provide the first experimental evidence supporting the causal role of ToM in the development of social competence in early childhood. PMID:26431737

Dietetic- nutritional, physical and physiological recovery methods post-competition in team sports. A review.

PubMed

Terrados, Nicolas; Mielgo-Ayuso, Juan; Delextrat, Anne; Ostojic, Sergej M; Calleja-González, Julio

2018-03-27

To a proper recovery, is absolutely necessary to know that athletes with enhanced recovery after maximal exercise are likely to perform better in sports. Recovery strategies are commonly used in team sports despite limited scientific evidence to support their effectiveness in facilitating optimal recovery and the players spend a much greater proportion of their time recovering than they do in training. According to authors, some studies investigated the effect of recovery strategies on physical performance in team sports, lack of experimental studies about the real origin of the fatigue, certify the need for further study this phenomenon. Thus, developing effective methods for helping athletes to recover is deemed essential. Therefore, the aim of this review is provide information for his practical application, based on scientific evidence about recovery in team sports.

Establishing Computer-Assisted Instruction to Teach Academics to Students with Autism as an Evidence-Based Practice.

PubMed

Root, Jenny R; Stevenson, Bradley S; Davis, Luann Ley; Geddes-Hall, Jennifer; Test, David W

2017-02-01

Computer-assisted instruction (CAI) is growing in popularity and has demonstrated positive effects for students with disabilities, including those with autism spectrum disorder (ASD). In this review, criteria for group experimental and single case studies were used to determine quality (Horner et al., Exceptional Children 71:165-179, 2005; Gersten et al., Exceptional Children 71:149-164, 2005; National Technical Assistance Center on Transition Center 2015). Included studies of high and adequate quality were further analyzed in terms of content, context, and specific instructional practices. Based on the NTACT criteria, this systematic review has established CAI as an evidence-based practice for teaching academics to students with ASD with support from 10 single-case and two group design studies of high or adequate quality. Suggestions for future research and implications for practice are discussed.

Evidence that amphotericin B mediates reactivation of latent Epstein-Barr virus in Hodgkin's lymphoma allowing cytotoxicity by acyclovir.

PubMed

Kast, Richard E

2006-04-30

This brief communication focuses on aspects of a recent case report (Yonsei Med J 2005;46:425-30) on a full and sustained remission of Hodgkin's lymphoma (HL) after a single day of chemotherapy. A septic episode required stopping chemotherapy and starting amphotericin B and acyclovir. Remission evidence was seen within days of starting these. A review of research supporting the notion that amphotericin B can reactivate latent Epstein-Barr virus and thus allow acyclovir to kill infected HL cells is given. Experimental work is required to confirm or refute this possibility. If successful, amphotericin B and acyclovir treatment could be extended to other EBV-driven cancers such as Burkitt's lymphoma, nasopharyngeal carcinoma and the occasional EBV-related epithelial cancer of the breast, colon, prostate, and others.

PSYCHIATRIC DISORDERS AND SLEEP

PubMed Central

Krystal, Andrew D.

2012-01-01

SYNOPSIS Psychiatric disorders and sleep are related in important ways. In contrast to the longstanding view of this relationship which viewed sleep problems as symptoms of psychiatric disorders, there is growing experimental evidence that the relationship between psychiatric disorders and sleep is complex and includes bi-directional causation. In this article we provide the evidence that supports this point of view, reviewing the data on the sleep disturbances seen in patients with psychiatric disorders but also reviewing the data on the impact of sleep disturbances on psychiatric conditions. Although much has been learned about the psychiatric disorders-sleep relationship, additional research is needed to better understand these relationships. This work promises to improve our ability to understand both of these phenomena and to allow us to better treat the many patients with sleep disorders and with psychiatric disorders. PMID:23099143

Dose-specific effects of transcutaneous electrical nerve stimulation (TENS) on experimental pain: a systematic review.

PubMed

Claydon, Leica S; Chesterton, Linda S; Barlas, Panos; Sim, Julius

2011-09-01

To determine the hypoalgesic effects of transcutaneous electrical nerve stimulation (TENS) parameter combinations on experimental models in healthy humans. Searches were performed using the electronic databases Ovid MEDLINE, CINAHL, AMED, and Web of Science (from inception to December 2009). Manual searches of journals and reference lists of retrieved trials were also performed. Randomized controlled trials (RCTs) were included in the review if they compared the hypoalgesic effect of TENS relative with placebo and control, using an experimental pain model in healthy human participants. Two reviewers independently selected the trials, assessed their methodologic quality and extracted data. Forty-three RCTs were eligible for inclusion. A best evidence synthesis revealed: Overall "conflicting" (inconsistent findings in multiple RCTs) evidence of TENS efficacy on experimental pain irrespective of TENS parameters used. Overall intense TENS has "moderate" evidence of efficacy (1 high-quality and 2 low-quality trials). Conventional TENS has overall conflicting evidence of efficacy, this is derived from "strong" evidence of efficacy (generally consistent findings in multiple high-quality RCTs) on pressure pain but strong evidence of inefficacy on other pain models. "Limited" evidence (positive findings from 1 RCT) of hypoalgesia exists for some novel parameters. Low-intensity, low-frequency, local TENS has strong evidence of inefficacy. Inappropriate TENS (using "barely perceptible" intensities) has moderate evidence of inefficacy. The level of hypoalgesic efficacy of TENS is clearly dependent on TENS parameter combination selection (defined in terms of intensity, frequency, and stimulation site) and experimental pain model. Future clinical RCTs may consider these TENS dose responses.

Framing messages about weight discrimination: impact on public support for legislation.

PubMed

Puhl, R M; Heuer, C; Sarda, V

2011-06-01

To assess the public support for potential legislation to prohibit weight-based discrimination against obese individuals in the United States, and to examine whether certain message frames about weight discrimination influence public support. Participants were randomly assigned to read one of the four paragraphs that framed the topic of weight discrimination in a distinct way (or a control condition with no paragraph). Participants were then asked to indicate their level of support for six antidiscrimination laws. A national sample of 1114 participants (48% women, 52% men), mean age 44.78 years (s.d. = 15.93). There was moderate support for several laws to prohibit weight-based discrimination, but gender differences were observed across experimental conditions indicating that some message frames may increase support for certain laws among women, but not men. However, message frames had no effect on support for laws with specific provisions to prohibit weight discrimination in the workplace, suggesting that public support for these particular legal measures is consistent and high (65% of men and 81% of women expressed support) regardless of how the issue of weight discrimination is framed to the public. The present findings provide evidence of current levels of public support for legislation to prohibit weight-based discrimination, and offer potential ways for policy makers and interest groups to communicate messages about weight discrimination in efforts to increase support.

Can the controversy about the putative role of the human female orgasm in sperm transport be settled with our current physiological knowledge of coitus?

PubMed

Levin, Roy J

2011-06-01

Spermatozoal uptake, facilitated by uterine contractions induced by oxytocin at orgasm during coitus, has been a long term concept. Studies attempting its support, however, have been poorly examined especially in the context of the changes in the female genital tract activated by sexual arousal. To examine experimental support for the concept. Using a variety of search engines, mainly peer reviewed articles and un-reviewed books were examined relating to sperm transport and function in the human female genital tract in the absence and presence of arousal to orgasm. Identifying evidence-based data to support authority-based opinion. All the experimental observations of sperm or model substitute's transport have been undertaken in women who were not sexually aroused. They fail to take into account that arousal creates vaginal tenting lifting the cervico-uterine complex into the false pelvis away from the ejaculated semen. This delays sperm uptake and transport making conclusions from these observations invalid in relation to transport during coitus. Studies injecting oxytocin have not used women in their sexually aroused state and used supraphysiological doses unlikely to be comparable with coitus and orgasm. The proposal that the transport of extra sperm by oxytocin-induced uterine contractions at orgasm is needed to facilitate fertility ignores possible harm from increased sperm numbers creating polyspermy and sperm enzyme release causing ovum degeneration, leading to decreased fertility. The role of sperm motility in their uptake from the vagina into the cervix as opposed to en bloc transfer through uterine archimyometrial-mediated transport in the absence of orgasm is at present unresolvable because of conflicting studies. The bulk of the reported evidence favors the conclusion that the female orgasm, with its concomitant central release of oxytocin, has little or no effective role in the transport of spermatozoa in natural human coitus. © 2010 International Society for Sexual Medicine.

The psychosocial effect of Tai Chi on nursing home residents.

PubMed

Lee, Linda Y K; Lee, Diana T F; Woo, Jean

2010-04-01

To determine the psychosocial effect of Tai Chi on nursing home residents. Moving into a nursing home usually imposes a certain degree of psychosocial challenge to older people. However, there is limited evidence suggesting a promising intervention that can promote the psychosocial health for this group. Although previous studies suggest that Tai Chi has the potential to enhance psychosocial well-being, existing evidence is deemed scarce and thus imposes a limitation on drawing out conclusions on this matter. Non-equivalent pretest-posttest control group design. A convenience sample of 139 residents from six nursing homes in Hong Kong was recruited for this study. The experimental group (n = 66) participated in a 26-week Tai Chi programme, while the control group (n = 73) continued its normal daily activities. The outcome measures included state self-esteem, the physical and mental component of health-related quality of life, social support network and social support satisfaction. Resident satisfaction was identified as a covariate because it demonstrated significant correlation with the outcome variables and, likewise, showed significant difference between the two study groups at baseline. Doubly multivariate analysis of covariance was performed to examine the effect of the intervention. Results indicate significant Group x Time interactions, with the experimental group experiencing significant improvement in the composite outcome of state self-esteem, the physical component of health-related quality of life and the mental component of health-related quality of life across the 26-week study period [F(6, 131) = 2.61, p = 0.02)]. No significant changes were detected regarding the effect of the Tai Chi programme on social support. Tai Chi practice is beneficial for nursing home residents. Tai Chi has unique characteristics that are particularly suitable in the practice of health exercise for nursing home residents. The inclusion of Tai Chi in residential care practice for older people is recommended.

Isochoric and isobaric freezing of fish muscle.

PubMed

Năstase, Gabriel; Lyu, Chenang; Ukpai, Gideon; Şerban, Alexandru; Rubinsky, Boris

2017-04-01

We have recently shown that, a living organism, which succumbs to freezing to -4 °C in an isobaric thermodynamic system (constant atmospheric pressure), can survive freezing to -4 °C in an isochoric thermodynamic system (constant volume). It is known that the mechanism of cell damage in an isobaric system is the freezing caused increase in extracellular osmolality, and, the consequent cell dehydration. An explanation for the observed survival during isochoric freezing is the thermodynamic modeling supported hypothesis that, in the isochoric frozen solution the extracellular osmolality is comparable to the cell intracellular osmolality. Therefore, cells in the isochoric frozen organism do not dehydrate, and the tissue maintains its morphological integrity. Comparing the histology of: a) fresh fish white muscle, b) fresh muscle frozen to -5 °C in an isobaric system and c) fresh muscle frozen to -5 °C I in an isochoric system, we find convincing evidence of the mechanism of cell dehydration during isobaric freezing. In contrast, the muscle tissue frozen to -5 °C in an isochoric system appears morphologically identical to fresh tissue, with no evidence of dehydration. This is the first experimental evidence in support of the hypothesis that in isochoric freezing there is no cellular dehydration and therefore the morphology of the frozen tissue remains intact. Copyright © 2017 Elsevier Inc. All rights reserved.

Frozen shoulder contracture syndrome - Aetiology, diagnosis and management.

PubMed

Lewis, Jeremy

2015-02-01

Frozen shoulder is a poorly understood condition that typically involves substantial pain, movement restriction, and considerable morbidity. Although function improves overtime, full and pain free range, may not be restored in everyone. Frozen shoulder is also known as adhesive capsulitis, however the evidence for capsular adhesions is refuted and arguably, this term should be abandoned. The aim of this Masterclass is to synthesise evidence to provide a framework for assessment and management for Frozen Shoulder. Although used in the treatment of this condition, manipulation under anaesthetic has been associated with joint damage and may be no more effective than physiotherapy. Capsular release is another surgical procedure that is supported by expert opinion and published case series, but currently high quality research is not available. Recommendations that supervised neglect is preferable to physiotherapy have been based on a quasi-experimental study associated with a high risk of bias. Physiotherapists in the United Kingdom have developed dedicated care pathways that provide; assessment, referral for imaging, education, health screening, ultrasound guided corticosteroid and hydro-distension injections, embedded within physiotherapy rehabilitation. The entire pathway is provided by physiotherapists and evidence exists to support each stage of the pathway. Substantial on-going research is required to better understand; epidemiology, patho-aetiology, assessment, best management, health economics, patient satisfaction and if possible prevention. Copyright © 2014 Elsevier Ltd. All rights reserved.

The Search for Cosmological Antimatter

NASA Technical Reports Server (NTRS)

Streitmatter, Robert E.

2004-01-01

For more than 40 years, experimentalists have searched in the cosmic radiation for evidence of antimatter which may have been created in the early Universe. The experimental evidence for cosmologically significant amounts of antimatter in the Universe is reviewed. There is no compelling evidence, either theoretical of experimental. However, the possibility is not completely ruled out.

Experimental Trials and "What Works?" in Education: The Case of Grammar for Writing

ERIC Educational Resources Information Center

Wyse, Dominic; Torgerson, Carole

2017-01-01

The place of evidence to inform educational effectiveness has received increasing attention internationally in the last two decades. An important contribution to evidence-informed policy has been greater attention to experimental trials including randomised controlled trials (RCTs). The aim of this paper is to examine the use of evidence,…

Metacognitive and multimedia support of experiments in inquiry learning for science teacher preparation

NASA Astrophysics Data System (ADS)

Bruckermann, Till; Aschermann, Ellen; Bresges, André; Schlüter, Kirsten

2017-04-01

Promoting preservice science teachers' experimentation competency is required to provide a basis for meaningful learning through experiments in schools. However, preservice teachers show difficulties when experimenting. Previous research revealed that cognitive scaffolding promotes experimentation competency by structuring the learning process, while metacognitive and multimedia support enhance reflection. However, these support measures have not yet been tested in combination. Therefore, we decided to use cognitive scaffolding to support students' experimental achievements and supplement it by metacognitive and multimedia scaffolds in the experimental groups. Our research question is to what extent supplementing cognitive support by metacognitive and multimedia scaffolding further promotes experimentation competency. The intervention has been applied in a two-factorial design to a two-month experimental course for 63 biology teacher students in their first bachelor year. Pre-post-test measured experimentation competency in a performance assessment. Preservice teachers worked in groups of four. Therefore, measurement took place at group level (N = 16). Independent observers rated preservice teachers' group performance qualitatively on a theory-based system of categories. Afterwards, experimentation competency levels led to quantitative frequency analysis. The results reveal differing gains in experimentation competency but contrary to our hypotheses. Implications of combining scaffolding measures on promoting experimentation competency are discussed.

The effect of rehearsal training on working memory span of children with fetal alcohol spectrum disorder.

PubMed

Loomes, Carly; Rasmussen, Carmen; Pei, Jacqueline; Manji, Shazeen; Andrew, Gail

2008-01-01

A key area of weakness in individuals with fetal alcohol spectrum disorder (FASD) is working memory, thus the goal of this study was to determine whether teaching children (aged 4-11) with FASD verbal rehearsal would increase their memory. Rehearsal training has been effective in other populations with working memory difficulties, so we hypothesized that children with FASD would also benefit from rehearsal training. Children were divided into an Experimental group, who received rehearsal training and a Control group, who did not receive training. All children were tested on digit span tasks over three sessions: a pretest (baseline) and then post-test 1 and post-test 2 (where only the Experimental group received rehearsal training). The Experimental group showed a significant increase in performance across session but the Control group did not. Children in the Experimental group performed significantly higher than the Control group on post-test 2 but not on the pretest or post-test 1. More children in the Experimental group showed behavioral evidence and self-report of rehearsal after training. Rehearsal training was successful at increasing the memory for numbers among children with FASD and may help to ameliorate working memory difficulties in FASD, ultimately supporting academic and developmental growth of children with FASD.

The maintenance of phenotypic divergence through sexual selection: An experimental study in barn swallows Hirundo rustica.

PubMed

Safran, Rebecca J; Vortman, Yoni; Jenkins, Brittany R; Hubbard, Joanna K; Wilkins, Matthew R; Bradley, Rachel J; Lotem, Arnon

2016-09-01

Previous studies have shown that sexual signals can rapidly diverge among closely related species. However, we lack experimental studies to demonstrate that differences in trait-associated reproductive performance maintain sexual trait differences between closely related populations, in support for a role of sexual selection in speciation. Populations of Northern Hemisphere distributed barn swallows Hirundo rustica are closely related, yet differ in two plumage-based traits: ventral color and length of the outermost tail feathers (streamers). Here we provide experimental evidence that manipulations of these traits result in different reproductive consequences in two subspecies of barn swallow: (H. r. erythrogaster in North America and H. r. transitiva in the East Mediterranean). Experimental results in Colorado, USA, demonstrate that males with (1) darkened ventral coloration and (2) shortened streamers gained paternity between two successive reproductive bouts. In contrast, exaggeration of both traits improved reproductive performance within H. r. transitiva in Israel: males with a combination treatment of darkened ventral coloration and elongated streamers gained paternity between two successive reproductive bouts. Collectively, these experimental results fill an important gap in our understanding for how divergent sexual selection maintains phenotype differentiation in closely related populations, an important aspect of the speciation process. © 2016 The Author(s). Evolution © 2016 The Society for the Study of Evolution.

Atomic oxygen recombination on quartz at high temperature: experiments and molecular dynamics simulation.

PubMed

Bedra, L; Rutigliano, M; Balat-Pichelin, M; Cacciatore, M

2006-08-15

A joint experimental and theoretical approach has been developed to study oxygen atom recombination on a beta-quartz surface. The experimental MESOX setup has been applied for the direct measurement of the atomic oxygen recombination coefficient gamma at T(S) = 1000 K. The time evolution of the relative atomic oxygen concentration in the cell is described by the diffusion equation because the mean free path of the atoms is less than the characteristic dimension of the reactor. The recombination coefficient gamma is then calculated from the concentration profile obtained by visible spectroscopy. We get an experimental value of gamma = 0.008, which is a factor of about 3 less than the gamma value reported for O recombination over beta-cristobalite. The experimental results are discussed and compared with the semiclassical collision dynamics calculations performed on the same catalytic system aimed at determining the basic features of the surface catalytic activity. Agreement, both qualitative and quantitative, between the experimental and the theoretical recombination coefficients has been found that supports the Eley-Rideal recombination mechanism and gives more evidence of the impact that surface crystallographic variation has on catalytic activity. Also, several interesting aspects concerning the energetics and the mechanism of the surface processes involving the oxygen atoms are pointed out and discussed.

Integrative review of implementation strategies for translation of research-based evidence by nurses.

PubMed

Wuchner, Staci S

2014-01-01

The purpose of this review was to synthesize and critique experimental and/or quasi-experimental research that has evaluated implementation strategies for translation of research-based evidence into nursing practice. Successfully implementing evidence-based research can improve patient outcomes. Identifying successful implementation strategies is imperative to move research-based evidence into practice. As implementation science gains popularity, it is imperative to understand the strategies that most effectively translate research-based evidence into practice. The review used the CINAHL and MEDLINE (Ovid) databases. Articles were included if they were experimental and/or quasi-experimental research designs, were written in English, and measured nursing compliance to translation of research-based evidence. An independent review was performed to select and critique the included articles. A wide array of interventions were completed, including visual cues, audit and feedback, educational meetings and materials, reminders, outreach, and leadership involvement. Because of the complex multimodal nature of the interventions and the variety of research topics, comparison across interventions was difficult. Many difficulties exist in determining what implementation strategies are most effective for translation of research-based evidence into practice by nurses. With these limited findings, further research is warranted to determine which implementation strategies most successfully translate research-based evidence into practice.

Cognitive, Behavioral, and Functional Consequences of Inadequate Sleep in Children and Adolescents

PubMed Central

Beebe, Dean W.

2011-01-01

Synopsis During the past few decades, studies using multiple research designs have examined whether sleep during childhood and adolescence is related to cognition, behavior, and other aspects of daytime functioning. This paper summarizes recent correlational, case-control, quasi-experimental, and experimental studies, highlighting how the strengths and limitations of each research design are complementary, thereby allowing one to more confidently draw conclusions when viewing the research literature as a whole. Viewed in this manner, published findings suggest that inadequate sleep quality and/or quantity can cause sleepiness, inattention and, very likely, other cognitive and behavioral deficits that significantly impact children and adolescents in important functional settings (e.g., school). This paper then integrates findings from longitudinal studies within a developmental psychopathology model. In this model, inadequate sleep is viewed as a noxious exposure that can, over time, fundamentally alter a child or adolescent's development, resulting in poorer long-term outcomes. Important research questions remain, but the available evidence supports the integration of sleep screening and interventions into routine clinical care and also supports advocacy for public policy changes to improve the sleep of children and adolescents. PMID:21600347

The effect of brain size evolution on feeding propensity, digestive efficiency, and juvenile growth

PubMed Central

Kotrschal, Alexander; Corral‐Lopez, Alberto; Szidat, Sönke; Kolm, Niclas

2015-01-01

One key hypothesis in the study of brain size evolution is the expensive tissue hypothesis; the idea that increased investment into the brain should be compensated by decreased investment into other costly organs, for instance the gut. Although the hypothesis is supported by both comparative and experimental evidence, little is known about the potential changes in energetic requirements or digestive traits following such evolutionary shifts in brain and gut size. Organisms may meet the greater metabolic requirements of larger brains despite smaller guts via increased food intake or better digestion. But increased investment in the brain may also hamper somatic growth. To test these hypotheses we here used guppy (Poecilia reticulata) brain size selection lines with a pronounced negative association between brain and gut size and investigated feeding propensity, digestive efficiency (DE), and juvenile growth rate. We did not find any difference in feeding propensity or DE between large‐ and small‐brained individuals. Instead, we found that large‐brained females had slower growth during the first 10 weeks after birth. Our study provides experimental support that investment into larger brains at the expense of gut tissue carries costs that are not necessarily compensated by a more efficient digestive system. PMID:26420573

NSDNA: a manually curated database of experimentally supported ncRNAs associated with nervous system diseases

PubMed Central

Wang, Jianjian; Cao, Yuze; Zhang, Huixue; Wang, Tianfeng; Tian, Qinghua; Lu, Xiaoyu; Lu, Xiaoyan; Kong, Xiaotong; Liu, Zhaojun; Wang, Ning; Zhang, Shuai; Ma, Heping; Ning, Shangwei; Wang, Lihua

2017-01-01

The Nervous System Disease NcRNAome Atlas (NSDNA) (http://www.bio-bigdata.net/nsdna/) is a manually curated database that provides comprehensive experimentally supported associations about nervous system diseases (NSDs) and noncoding RNAs (ncRNAs). NSDs represent a common group of disorders, some of which are characterized by high morbidity and disabilities. The pathogenesis of NSDs at the molecular level remains poorly understood. ncRNAs are a large family of functionally important RNA molecules. Increasing evidence shows that diverse ncRNAs play a critical role in various NSDs. Mining and summarizing NSD–ncRNA association data can help researchers discover useful information. Hence, we developed an NSDNA database that documents 24 713 associations between 142 NSDs and 8593 ncRNAs in 11 species, curated from more than 1300 articles. This database provides a user-friendly interface for browsing and searching and allows for data downloading flexibility. In addition, NSDNA offers a submission page for researchers to submit novel NSD–ncRNA associations. It represents an extremely useful and valuable resource for researchers who seek to understand the functions and molecular mechanisms of ncRNA involved in NSDs. PMID:27899613

The potential role of subclinical Bordetella Pertussis colonization in the etiology of multiple sclerosis.

PubMed

Rubin, Keith; Glazer, Steven

2016-04-01

It is established that (1) subclinical Bordetella pertussis colonization of the nasopharynx persists in highly vaccinated populations, and (2) B. pertussis toxin is a potent adjuvant that, when co-administered with neural antigens, induces neuropathology in experimental autoimmune encephalomyelitis, the principle animal model of multiple sclerosis. Building on these observations with supporting epidemiologic and biologic evidence, we propose that, contrary to conventional wisdom that subclinical pertussis infections are innocuous to hosts, B. pertussis colonization is an important cause of multiple sclerosis. Copyright © 2015 The Authors. Published by Elsevier GmbH.. All rights reserved.

[Magnesium sulphate in the treatment of ischemic-hypoxic neonatal encephalopathy].

PubMed

Kornacka, M K

2001-01-01

Hypoxic-ischaemic encephalopathy (HIE) remains one of the most important neurological complications in full and near full term newborns. During HIE glutamate and other excitatory neurotransmitters are released and progressive energy failure in brain is observed. Toxicity of glutamate plays the main role in brain injury. Glutamate activates the specific receptors that, in turn, mediate an overwhelming influx of calcium into the postsynaptic neuron. The pathological changes are located particularly in hippocampus. Magnesium sulfate has been used safely for years to treat preclampsia. The animal experimental evidence support a neuroprotective role for magnesium in HIE.

Laser ablation and column formation in silicon under oxygen-rich atmospheres

NASA Astrophysics Data System (ADS)

Pedraza, A. J.; Fowlkes, J. D.; Lowndes, D. H.

2000-11-01

The microstructure formed at the surface of silicon by cumulative pulsed-laser irradiation in oxygen-rich atmospheres consists of an array of microcolumns surrounded by microcanyons and microholes. Formation of SiOx at the exposed surface of silicon is most likely responsible for the occurrence of etching/ablation that causes the continuous deepening of canyons and holes. The growth mechanism of columns that is supported by the experimental evidence presented here is a process in which the columns are fed at their tips by the silicon-rich ablation plasma produced during pulsed-laser irradiation.

Cryptic genetic variation, evolution's hidden substrate

PubMed Central

Paaby, Annalise B.; Rockman, Matthew V.

2016-01-01

Cryptic genetic variation is invisible under normal conditions but fuel for evolution when circumstances change. In theory, CGV can represent a massive cache of adaptive potential or a pool of deleterious alleles in need of constant suppression. CGV emerges from both neutral and selective processes and it may inform how human populations respond to change. In experimental settings, CGV facilitates adaptation, but does it play an important role in the real world? We review the empirical support for widespread CGV in natural populations, including its potential role in emerging human diseases and the growing evidence of its contribution to evolution. PMID:24614309

Theoretical evidence for a first-order liquid-liquid phase transition in gallium.

PubMed

Carvajal Jara, Diego Alejandro; Fontana Michelon, Mateus; Antonelli, Alex; de Koning, Maurice

2009-06-14

We report on theoretical results that lend support to recent experimental observations suggesting the existence of a first-order liquid-liquid phase transformation (LLPT) in gallium. Using molecular dynamics simulation based on a modified embedded-atom model, we observe a transition from a high-density to a low-density liquid in the supercooled regime. The first-order character of the transition is established through the detection of the release of latent heat and our findings suggest that the LLPT terminates in a critical point that is located in the tensile-strained domain of the metastable phase diagram.

Nature of native defects in ZnO.

PubMed

Selim, F A; Weber, M H; Solodovnikov, D; Lynn, K G

2007-08-24

This study revealed the nature of native defects and their roles in ZnO through positron annihilation and optical transmission measurements. It showed oxygen vacancies are the origin for the shift in the optical absorption band that causes the red or orange coloration. It also revealed experimental evidence that the donor nature of oxygen vacancy is approximately 0.7 eV. In addition, this work showed the Zn interstitial was not the donor in the as-grown ZnO and supported recent calculations that predicted hydrogen in an oxygen vacancy forms multicenter bonds and acts as a shallow donor.

On the structural origins of ferroelectricity in HfO{sub 2} thin films

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

Sang, Xiahan; Grimley, Everett D.; LeBeau, James M.

2015-04-20

Here, we present a structural study on the origin of ferroelectricity in Gd doped HfO{sub 2} thin films. We apply aberration corrected high-angle annular dark-field scanning transmission electron microscopy to directly determine the underlying lattice type using projected atom positions and measured lattice parameters. Furthermore, we apply nanoscale electron diffraction methods to visualize the crystal symmetry elements. Combined, the experimental results provide unambiguous evidence for the existence of a non-centrosymmetric orthorhombic phase that can support spontaneous polarization, resolving the origin of ferroelectricity in HfO{sub 2} thin films.